Bacteria

Annu Rev Plant Biol, 2002, 53, 477 - 501
A new moss genetics: targeted mutagenesis in Physcomitrella patens; Schaefer DG; The potential of moss as a model system to study plant biology is associated with their relatively simple developmental pattern that nevertheless resembles the basic organization of the body plan of land plants, the direct access to cell-lineage analysis, their similar responses to plant growth factors and environmental stimuli as those observed in other land plants, and the dominance of the gametophyte in the life cycle that facilitates genetic approaches . Transformation studies in the moss Physcomitrella patens have revealed a totally unique feature for plants, i.e., that foreign DNA sequences integrate in the genome preferentially at targeted locations by homologous recombination, enabling for the first time in plants the application of the powerful molecular genetic approaches used routinely in bacteria, yeast, and since 1989, the mouse embryonic stem cells . This article reviews our current knowledge of Physcomitrella patens transformation and its unique suitability for functional genomic studies.

Planta Med, 2002 Aug, 68(8), 714 - 8
Evaluation of salicin as an antipyretic prodrug that does not cause gastric injury; Akao T et al.; Pharmacokinetic and pharmacological studies were performed to compare the antipyretic effects of salicin (SL), saligenin (SG, an aglycone of SL) and salicylic acid (SA, an active metabolite of SL) in rats . When SL was administered orally to rats, SA appeared slowly in the plasma and levels increased gradually, in contrast to the rapid appearance observed after oral administration of sodium salicylate (SANa) or SG . Orally administered SL did not affect the rectal temperatures of afebrile rats at a dose of 5 mmol/kg; at this dose, SANa and SG lowered body temperature significantly . However, it significantly reduced yeast-induced fever, producing a normal body temperature, and completely prevented fever when administered simultaneously with yeast . SL did not induce gastric lesions even at a dose of 5 mmol/kg; conversely, SANa and SG induced severe gastric lesions in a dose-dependent manner at 1, 2.5 and 5 mmol/kg . Poor absorption of SL and rapid absorption of SA and SG were confirmed in an in vivo system, as well as in an in vitro system using everted rat jejunal sacs . Only small amounts of SA and SG were detected in the intestinal tracts of rats 1 h after oral administration, whereas more than 50 % of an SL dose was recovered as SL and SG from the intestinal tracts 1 h after treatment and 15.8 % of the dose was still present as SG 4 h after administration . When given to germ-free rats, 19.8 % of the SL dose was recovered intact, mainly from the cecum, and no SG was detected even at 4 h after treatment . These results indicate that SL is a prodrug which is gradually transported to the lower part of the intestine, hydrolyzed to SG by intestinal bacteria, and converted to SA after absorption . It thus produces an antipyretic action without causing gastric injury.

Spine, 2002 Sep 1, 27(17), E396 - 8
Pseudogout attack of the lumbar facet joint: a case report; Fujishiro T et al.; STUDY DESIGN: A case of acute low back pain caused by pseudogout attack of the lumbar facet joint is reported . OBJECTIVE: To report a new cause of acute low back pain previously unreported in the literature . SUMMARY OF BACKGROUND DATA: There have been some reports of lumbar spinal stenosis caused by calcium pyrophosphate dihydrate crystal deposition . However, there are no known reports of pseudogout attack of the lumbar facet joint . METHODS: An axial magnetic resonance imaging scan demonstrated joint effusion at the level of the bilateral L4-L5 facet joint . Aspiration of the left L4-L5 facet joint yielded 1.5 mL of pus-like synovial effusion . Multiple cultures of synovial fluid tested negative for bacteria and fungi, whereas compensated polarized light microscopy revealed monoclinic or triclinic crystals with a positive birefringence . RESULTS: The symptoms of acute low back pain lasted for 3 days . Local and systemic inflammatory signs, as well as symptoms, gradually improved after joint aspiration . A follow-up evaluation 8 months after lumbar facet joint aspiration showed complete resolution of pain and no neurologic deficit . CONCLUSIONS: Pseudogout attack of the lumbar facet joint is rare, but this clinical entity should be added to the differential diagnosis of acute low back pain.

Proc Natl Acad Sci U S A, 2002 Sep 17, 99(19), 12236 - 41 Epub 2002 Sep 09.
Experimental control of pancreatic development and maintenance; Holland AM et al.; To investigate the role of the HOX-like homeoprotein PDX1 in the formation and maintenance of the pancreas, we have genetically engineered mice so that the only source of PDX1 is a transgene that can be controlled by the application of tetracycline or its analogue doxycycline . In these mice the coding region for the tetracycline-regulated transactivator (tTA(off)) has replaced the coding region of the endogenous Pdx1 gene to ensure correct temporal and spatial expression of the regulatable transactivator . In the absence of doxycycline, tTA(off) activates the transcription of a bicistronic transgene encoding PDX1 and an enhanced green fluorescent protein reporter, which acts as a visual marker of transgene expression in living cells . Expression of the transgene-encoded PDX1 rescues the Pdx1-null phenotype; the pancreata of these mice develop and function normally . The rescue is conditional; doxycycline-mediated repression of the transgenic Pdx1 throughout gestation recapitulates the Pdx1 null phenotype . Moreover, application of doxycycline at mid-pancreogenesis blocks further development . Adult animals of the rescue genotype that were treated with doxycycline for 3 weeks shut off Pdx1 expression, decreased insulin production, and lost the ability to maintain glucose homeostasis . These results demonstrate the feasibility of controlling the formation of an organ during embryogenesis in utero and the maintenance of the mature organ through the experimental manipulation of a key developmental regulator.

Trends Biotechnol, 2002 Oct, 20(10), 433 - 7
Optimizing lipases and related enzymes for efficient application; Bornscheuer UT et al.; Although numerous reactions have been performed using lipases and related enzymes (e.g . esterases and phospholipases), it is still a challenge to identify the most suitable biocatalyst and best reaction conditions for an efficient application . Frequently used methods such as immobilization and optimization of the reaction medium cannot be transferred from one reaction system or substrate to another . However, in the past few years, rational protein design and directed evolution have emerged as efficient alternative methods to optimize biocatalytic reactions.

Trends Biotechnol, 2002 Oct, 20(10), 420 - 5
Trehalose production: exploiting novel approaches; Schiraldi C et al.; Trehalose (alpha-D-glucopyranosyl alpha-D-glucopyranoside) is a unique sugar capable of protecting biomolecules against environmental stress . It is a stable, colorless, odor-free and non-reducing disaccharide, and is widespread in nature . Trehalose has a key role in the survival of some plants and insects, termed anhydrobionts, in harsh environments, even when most of their water body is removed . The properties of these types of organisms drove attention towards the study of trehalose . Since then, it proved to be an active stabilizer of enzymes, proteins, biomasses, pharmaceutical preparations and even organs for transplantation . Recently, trehalose has been accepted as a safe food ingredient by the European regulation system following approval by the US Food and Drug Administration . The wide range of applications of this sugar has increased the interest of many research groups into the development of novel and economically feasible production systems . This article provides a comprehensive review of the current achievements in the biotechnological production of trehalose.

Environ Microbiol, 2002 Sep, 4(9), 517 - 24
Analysis of sMMO-containing type I methanotrophs in Lake Washington sediment; Auman AJ et al.; Methane-oxidizing bacteria (methanotrophs) containing soluble methane monooxygenase (sMMO) are of interest in natural environments due to the high co-metabolic activity of this enzyme with contaminants such as trichloroethylene . We have analysed sMMO-containing methanotrophs in sediment from a freshwater lake . Environmental clone banks for a gene encoding a diagnostic sMMO subunit (mmoX) were generated using DNA extracted from Lake Washington sediment and subjected to RFLP analysis . Representatives from the six RFLP groups were cloned and sequenced, and all were found to group with Type I Methylomonas mmoX, although a majority were divergent from known Methylomonas mmoX sequences . Direct hybridization of Lake Washington sediment DNA was carried out using a series of sMMO- and Methylomonas-specific probes to assess the significance of these sMMO-containing Methylomonas-like strains in the sediment . The total sMMO-containing population and the sMMO-containing Methylomonas-like population were estimated to be similar to previous estimates for total methanotrophs and Type I methanotrophs . These results suggest that the major methanotrophic population in Lake Washington sediment consists of sMMO-containing Methylomonas-like (Type I) methanotrophs . The whole-cell TCE degradation kinetics of such a strain, LW15, isolated from this environment, were determined and found to be similar to values reported for other sMMO-containing methanotrophs . The numerical significance of sMMO-containing Methylomonas-like methanotrophs in a mesotrophic lake environment suggests that these methanotrophs may play an important role in methanotroph-mediated transformations, including co-metabolism of halogenated solvents, in natural environments.

Biochemistry, 2002 Sep 17, 41(37), 11200 - 10
The two histidine axial ligands of the primary electron donor chlorophylls (P700) in photosystem I are similarly perturbed upon P700+ formation; Breton J et al.; The extent of delocalization of the positive charge in the oxidized dimer of chlorophyll (Chl) constituting P700, the primary electron donor of photosystem I (PSI), has been investigated by analyzing the perturbation upon P700(+) formation of infrared (IR) vibrational modes of the two His axial ligands of the two P700 Chl molecules . Fourier transform IR (FTIR) difference spectra of the photooxidation of P700 in PSI core complexes isolated from Synechocystis sp . PCC 6803 isotopically labeled either globally with (15)N or more specifically with (13)C on all the His residues reveal isotopic shifts of a differential signal at 1102/1108 cm(-)(1) . This signal is assigned to a downshift upon P700(+) formation of the predominantly C(5)-Ntau imidazole stretching mode of His residue(s) . The amplitude of this signal is reduced by approximately half in FTIR spectra of Synechocystis mutants in which His PsaB 651, the axial ligand to one of the two Chl molecules in P700, is replaced by Cys, Gln, or Leu . These observations provide further evidence that the positive charge in P700(+) is essentially delocalized over the two Chl molecules, in agreement with a previous FTIR study in which the frequency of the vibrational modes of the 9-keto and 10a-ester C=O groups of the two Chl's in P700, P700(+), and (3)P700 were firmly established for the first time {Breton, J., et al . (1999) Biochemistry 38, 11585-11592} . Only limited perturbations of the amplitude and frequency of the 9-keto and 10a-ester C=O bands of the P700 Chl are elicited by the mutations . On the basis of comparable mutational studies of the primary electron donor in purple bacteria, these perturbations are attributed to small molecular rearrangements of the Chl macrocycle and substituents caused by the repositioning of the P700 dimer in the new protein cavity generated by the mutations . It is proposed that the perturbation of the FTIR spectra upon mutation of a His axial ligand of the P700 Chl recently reported in Chlamydomonas reinhardtii {Hastings, G., et al . (2001) Biochemistry 40, 12943-12949} can be explained by the same effect without the need for a new assignment of the C=O bands of P700 . The distribution of charge/spin in P700(+) and (3)P700 determined by FTIR spectroscopy is discussed in relation with the contrasting interpretations derived from recent magnetic resonance experiments.

Dev Biol (Basel), 2002, 108, 129 - 36
New developments in biological standardisation: commentary on the poster session on advances in transfusion safety; Seghatchian J; The 21 presentations have been arranged into two broad inter-related groups: (i) Quality of therapeutic preparations and studies on viral/bacterial inactivation procedures . (ii) Diagnostic assays for viral safety and quality control of blood components . Furthermore, in line with the main theme of this symposium, I have attempted to provide an overview of pertinent continuing investigation of blood component safety and supply, the "twin pillars" of transfusion therapy, focusing on the three pointers (3Ps) of the quality system-patient, process and product.

Uisahak, 1999, 8(2), 269 - 77
{Possibility in unification of oriental and western medicine education by combination of educational curricula}; Kim JS et al.; The authors attempted a possibility of unification in the educational curricula of both Oriental and Western medical schools for the unification of two medicines . Historically the two medicines were originated from the most primitive state like instinctive method and we can say two medicines were entirely the same . However, after abrupt and current development of science in the 19th century by discovery of microscope and bacteria as well as cells, changed medicine into recent unbelievable current medicine from old ancient style medicine like Chinese Medicine which was just the remnant old medicine . The unification of educational curricula is thought to be possible to combine each other by technical adjustment from mutual understanding and cooperation for the most high quality of peoples lives . There were good equality to partial correspondences between two educational curricula around 90% at two pre-and schools from the study to analyse . The combined medicine is thought to be more efficient to the diagnosis and treatment of patients because of the effectiveness of Oriental medicine in certain disease conditions like chronic illness by acupuncture as a alternative medicine or herbs.

Eur J Immunol, 2002 Sep, 32(9), 2393 - 400
Endothelin-2 is a macrophage chemoattractant: implications for macrophage distribution in tumors; Grimshaw MJ et al.; Endothelins (ET-1, ET-2 and ET-3) are 21-amino acid vasoactive peptides that bind to G-protein-linked transmembrane receptors, ET-RA and ET-RB . As well as modulating vasoconstriction, endothelins regulate growth in several cell types and may also affect differentiation, inflammation and angiogenesis . Both macrophages and endothelins are found in areas of hypoxia in solid tumors and ET-2 expression may be modulated by hypoxia in some tumors . As the peptide structure of mature endothelins is similar to that of CXC chemokines, we asked if endothelins contribute to control of macrophage distribution in tumors . We found that ET-2 is a chemoattractant for macrophages and THP-1 monocytic cells, but not for freshly isolated monocytes . The chemotactic response to ET-2 shows a typical bell-shaped response curve . Experiments with endothelin receptor antagonists showed that migration to ET-2 is mediated via the ET-RB receptor . Moreover, monocytes do not express ET-RB . Chemotaxis towards ET-2 is via the MAPK pathway: p44 and p42 are phosphorylated when THP-1 cells are stimulated with ET-2, and the MAPKK inhibitor PD98059 stops chemotaxis . As with 'classical' chemokines, migration toET-2 is also inhibited by hypoxia and by pertussis toxin . As well as its chemotactic properties, ET-2 leads to activation of macrophages . In human breast tumors that express ET-2, endothelins and ET-RB expressing macrophages often co-localized . While shorter than 'classical' chemokines, ET-2 shares a similar peptide sequence with chemokines and may signal via a similar receptor and MAPK-mediated pathway . Furthermore, ET-2 expression by tumors may modulate the behavior of macrophages such that activated cells accumulate in areas of hypoxia.

Prog Nucleic Acid Res Mol Biol, 2002, 72, 165 - 221
Jasmonates and octadecanoids: signals in plant stress responses and development; Wasternack C et al.; Plants are sessile organisms . Consequently they have to adapt constantly to fluctuations in the environment . Some of these changes involve essential factors such as nutrients, light, and water . Plants have evolved independent systems to sense nutrients such as phosphate and nitrogen . However, many of the environmental factors may reach levels which represent stress for the plant . The fluctuations can range between moderate and unfavorable, and the factors can be of biotic or abiotic origin . Among the biotic factors influencing plant life are pathogens and herbivores . In case of bacteria and fungi, symbiotic interactions such as nitrogen-fixating nodules and mycorrhiza, respectively, may be established . In case of insects, a tritrophic interaction of herbivores, carnivores, and plants may occur mutualistically or parasitically . Among the numerous abiotic factors are low temperature, frost, heat, high light conditions, ultraviolet light, darkness, oxidation stress, hypoxia, wind, touch, nutrient imbalance, salt stress, osmotic adjustment, water deficit, and desiccation . In the last decade jasmonates were recognized as being signals in plant responses to most of these biotic and abiotic factors . Signaling via jasmonates was found to occur intracellularly, intercellularly, and systemically as well as interorganismically . Jasmonates are a group of ubiquitously occurring plant growth regulators originally found as the major constituents in the etheric oil of jasmine, and were first suggested to play a role in senescence due to a strong senescence-promoting effect . Subsequently, numerous developmental processes were described in which jasmonates exhibited hormone-like properties . Recent knowledge is reviewed here on jasmonates and their precursors, the octadecanoids . After discussing occurrence and biosynthesis, emphasis is placed upon the signal transduction pathways in plant stress responses in which jasmonates act as a signal . Finally, examples are described on the role of jasmonates in developmental processes.

Life Sci Space Res, 1971, 9, 75 - 80
Theoretical and experimental decisions in the creation of an artificial ecosystem for human life support in space; Kirensky LV et al.; All of man's former space flights were not real ventures into space in the biological sense, as his life was supported with unregenerated earth supplies . The coming stage of space exploration requires man's long existence in the cosmos and on the other planets . This stage of man's activity outside the earth become possible only by creating small man-made ecosystems, permitting the support of his metabolism by the recycling of substances of the terrestrial biosphere . Creation of such systems is a new scientific and technical task . Man-made ecosystems are a new product of man's activity, which have no complete analogy, either in nature, or in technology . Stochastic mechanisms, which stabilize biogeocenosis, cannot be effective in small ecosystems . A technique of parametric control over biosynthesis made it possible to calculate, and put to practice, an ecosystem for man with a cyclic regeneration of the atmosphere, water and, partially, food . The specific bio-technological properties of small man-made ecosystems are being analysed . The possibility of their application for man's excursions into space and for the settlement of other planets is being considered.

Life Sci Space Res, 1971, 9, 169 - 72
The influence of ultra-high vacuum on crystalline enzymes; Lysenko SV et al.; The exploration of physical conditions in space is closely related to the study of the influence of space factors on biological objects . The study of high vacuum is of particular importance because its effects are as yet imperfectly understood . Micro-organisms are suitable models for these investigations . It has already been found that in reference to high vacuum, micro-organisms may be divided into two groups: resistant and nonresistant forms . Bacterial and actinomycetal spores and conidia of Aspergillus are classified as the resistant forms . Parallel with these, rod-shaped non-sporeforming bacteria, yeasts and conidia of Penicillium, were found to be non-resistant forms . The mechanism of resistance and death of micro-organisms under high vacuum is still not clearly understood . Because of this the investigation employing such important macromolecules as crystalline cytochrome C, catalase, peroxidase and ATP have been carried out . These compounds were exposed to a high vacuum (10(-8)-10(-9) mm Hg) over a period of 72 hours . Then the weighed samples taken from treated specimens and controls were dissolved firstly in a phosphate buffer solution (pH=6.8-7.2) and were then diluted by this buffer up to a concentration of 10(-9) mg ml . The solutions obtained were investigated by the chemiluminescent method . It was found that high vacuum effects gave rise to a slight decrease (up 7%) in enzyme activity in concentrated solutions and to a significant inactivation (up to 30%) in diluted ones.

Life Sci Space Res, 1971, 9, 159 - 65
Some potentialities of living organisms under simulated Martian conditions; Lozina-Lozinsky LK et al.; Temperature, humidity, pressure, composition of the atmosphere and radiation are the main factors conditioning life on the surface of Mars . When studying the Martian ecology, one must know the total effect of these factors . One may expect that, as a result of adaptation to low temperatures, there is a corresponding shift in the temperature optimum of enzymatic activity . Dryness is the main obstacle to active life . We suggest the presence of some soil moisture and water vapour . Moreover, there can be areas of permafrost . This minimum supply of water and periodic fluctuations of humidity may create conditions for the existence of drought-resistant organisms . Decreased atmospheric pressure alone does not affect micro-organisms, plants, protozoa and even insects . Ciliates reproduce in a flowing atmosphere of pure nitrogen containing 0.0002-0.0005% oxygen as an impurity . Protozoa may also develop in an atmosphere of 98-99% carbon dioxide mixed with 1% O2 . Therefore, even traces of oxygen in the Martian atmosphere would be sufficient for aerobic unicellular organisms . Cells and organisms on earth have acquired various ways of protection from uv light, and therefore may increase their resistance further by adaptation or selection . The resistance of some organisms to ionizing radiation is high enough to enable them to endure hard ionizing radiation of the sun . Experiments with unicellular {correction of unicellar} organisms show that the effect of short wave uv radiation depends on the intensity of visible light, long-wave solar uv radiation, temperatures, cell repair processes, and the state of cell components, i.e . whether the cell was frozen, dried or hydrated.

Life Sci Space Res, 1968, 6, 94 - 9
On the interrelations between ultraviolet and visible light during their simultaneous action on the cell; Zaar EI; Beyond the Earth's atmosphere, ultraviolet (UV) light that is a component of the Sun's spectrum appears as one of the limiting factors to life in space and on the planets which have no ozone layer in their atmosphere . At early stages in the evolution of life, the Earth's atmosphere contained neither free oxygen nor the layers serving as a screen for short-wave UV light . Under such conditions, the UV radiation lasted for 8-10 hours a day . Similar radiation conditions may be found on Mars . Still, we do not know to what extent the photo-reactivating region of sun radiation (3000-5490 angstroms) can protect cells from the action of short UV light . Therefore, it will be of interest to study a prolonged action of UV radiation on living systems (protozoa, bacteria, fungi, animal and plant cells) in the presence of visible rays capable of reactivating UV damage . We subjected infusoria (Paramecium caudatum) to prolonged action of UV light (2537 angstroms) . The cells were irradiated daily for 8-16 hours with doses of 1.5-40 and 120 mkvt . A sharp reduction in the rate of division and the lethality to the infusoria were observed from the second to the fifth day of experimentation . In the light variant, UV radiation was performed simultaneously with the application of visible light (2800-15000 lux) . In such conditions, the cells kept their normal rate of division for 12 days . In the next 30 days without irradiation, no deviation from the normal rate was noted . The experimental results permit the conclusion that under certain conditions of interaction between visible and UV light, UV does not produce a deleterious effect on cell division.

Life Sci Space Res, 1968, 6, 41 - 4
Problem of reproduction of food protein by autotrophic organisms in extraterrestrial conditions; Fofanov VI et al.; To supply a man during his prolonged stay in extraterrestrial space with dietary protein by storing it in space vehicles seems to be impractical . Protein reproduction could be realized at present only by biosynthesis, which is possible with the autotrophic organisms and is the most economic, universal and therefore quite possible for use in life-support systems . In the paper, experimental results are presented on the biological value of single-celled algae proteins . The results obtained suggested that algae biomass in human rations could not be used in quantities needed for turnover of the components of the space-cabin atmosphere . The main obstacles lie in a hard broken algae shell, a large quantity of pigment, "allergization" of persons with biomass included in their rations, lack of some aminoacids in the protein, as well as man's psychological negativism to algae as a food product . Use of single-celled algae as a food source in the future will depend on improvement of its technological and biological management . A possible use of hydrogen-reducing bacteria as a biological dietary protein product is discussed.

Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai), 1997, 29(1), 53 - 60
Comparison of Different Effects of Chloroacetates on Electron Transports in PS II and in the Reaction Center of Rb . sphaeroides 601; Yu H et al.; Chloroacetates displayed different effects on electron transports in the photosynthetic reaction center of purple bacteria (Rb.sphaeroides 601) and in the photosystem II (PS II) of higher plants . Decays of chlorophyII a fluorescence measured after actinic flashes show that chloroacetates inhibit the electron transport from Q(A)(-) to Q(B) (Q(B)(-)) and the equilibrium between Q(A)(-)Q(B) (Q(B)(-)) and Q(A)Q(B)(-) (Q(B)(2-)), acting on electron transport as well as proton transduction . The study on PSII electron transport indicates another inhibition site of chloroacetate at the oxidation side of PSII . Chloroacetates up to 500 mM have no inhibition on the DCPIPH(2) right curved arrow MV electron transport in the RS601's chromatophores . Dissociation constants of OP and trichloroacetates from RS601 reaction center were assessed to be 1.1x10(-3) M and from Dixon curve respectively . The differences on aspects of structures and functions between RS601 reaction center and PS II were discussed.

Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai), 1997, 29(1), 46 - 52
The Characteristics of DCPIPH(2) right curved arrow MV Electron Transport in Rb . sphaeroides 601; Zeng XH et al.; The absorption spectrum and fluorescence emission spectrum of RS601 were found to keep the typical characteristics of those of the purple nonsulfide bacteria Rb . sphaeroides . Under illumination, methyl viologen was reduced by RS601 chromatophores in the presence of DCPIPH(2) as the electron donor, setting up a standard noncyclic electron transport . o-phenanthroline with I(50) of 1.0 mM inhibited the DCPIPH(2) right curved arrow MV electron transport . Antimycin A did not inhibit the DCPIPH(2) right curved arrow MV electron transport and had no I(50) . The results suggested that the exact site where methyl viologen accepted electron should locate between the secondary electron acceptor, Q(B), and cyt b, but not at the Q(A) binding site as indicated before . The difference of electron transport between reduced sides of reaction centers of Rb . sphaeroides and Rs . rubrum was discussed.

Rev Inst Med Trop Sao Paulo, 2002 Jul-Aug, 44(4), 209 - 12
Mycoplasma pneumoniae and Chlamydia pneumoniae in calcified nodules of aortic stenotic valves; Higuchi Mde L et al.; Aortic Valve Stenosis (AVS) has been explained as an atherosclerotic process of the valve as they often exhibit inflammatory changes with infiltration of macrophages, T lymphocytes and lipid infiltration . The present study investigated whether the bacteria Chlamydia pneumoniae (CP) and Mycoplasma pneumoniae (MP), detected previously in atherosclerotic plaques, are also present in AVS . Ten valves surgically removed from patients with AVS were analyzed by immunohistochemistry, in situ hybridization, and electron microscopy . The mean and standard deviation of the percentage areas occupied by CP antigens and MP - DNA were respectively 6.21 +/- 5.41 and 2.27 +/- 2.06 in calcified foci; 2.8 +/- 3.33 and 1.78+/- 3.63 in surrounding fibrotic areas, and 0.21 +/- 0.17 and 0.12 +/- 0.13 in less injured parts of the valve . There was higher amount of CP and MP in the calcified foci and in the surrounded fibrosis than in more preserved valvular regions . In conclusion, the fact that there were greater amounts of CP and MP in calcification foci of AVS favors the hypothesis that AS is not an inevitable degenerative process due to aging, but rather that it may be a response to the presence of these bacteria, similarly to the morphology detected in atherosclerosis damage.

J Biol Chem, 2002 Nov 8, 277(45), 42852 - 8 Epub 2002 Sep 05.
A coregulatory role for the TRAP-mediator complex in androgen receptor-mediated gene expression; Wang Q et al.; The human thyroid hormone receptor-associated protein (TRAP)-Mediator complex was originally identified as a large multimeric complex that copurifies with the thyroid hormone receptor (TR) from HeLa cells and markedly enhances TR-mediated transcription in vitro . More recent studies have implicated TRAP-Mediator as a coactivator for a broad range of nuclear hormone receptors as well as other classes of transcriptional activators . Here we present evidence that TRAP-Mediator plays a functional role in androgen receptor (AR)-mediated transcription . We show that several subunits of the complex ligand-dependently coimmunoprecipitate with AR from both prostate cancer LNCaP cells and from HeLa cells stably transfected with AR . The 220-kDa subunit of the complex (TRAP220) can contact the ligand-binding domain of AR in vitro, possibly implicating TRAP220 involvement in targeting AR to the holocomplex . Consistent with a TRAP-Mediator coactivator role, transient overexpression of the TRAP220, TRAP170, and TRAP100 subunits enhanced ligand-dependent transcription by AR in cultured cells . Finally, chromatin immunoprecipitation assays show that TRAP220 is recruited to the androgen-responsive prostate-specific antigen gene promoter in vivo in ligand-stimulated LNCaP cells . Collectively, these data suggest that TRAP-Mediator may play an important coregulatory role in AR-mediated gene expression.

J Infect, 2002 Aug, 45(2), 99 - 106
Diarrhea, CD4 counts and enteric infections in a community-based cohort of HIV-infected adults in Uganda; Brink AK et al.; OBJECTIVES: To examine relationships between diarrhoea, CD4 cell counts and stool pathogens in a community-based cohort of HIV-infected adults in Uganda . PATIENTS AND METHODS: Stool specimens, obtained between October 1995 and December 1997, were linked to patients' symptoms and laboratory results . The relationship between CD4 counts and symptoms was tested using the Wilcoxon rank-sum test and those between organisms and diarrhoea using first a univariate Mantel-Haenszel analysis and then a logistic regression model adjusted for CD4 count and multiple organisms . RESULTS: 1,213 HIV-infected individuals (70% women, median CD4 cell count at enrollment 215 cells/microl) were followed for 1,224 person years of observation (pyo) . 484 stool samples were examined, 357 from patients with diarrhoea . The rate of diarrhoea was 661 episodes per 1,000 pyo . CD4 counts were significantly lower in individuals with diarrhoea than those without (P < 0.001, Wilcoxon rank-sum test) . Forty-nine percent of diarrhoeal stools and 39% of stools from asymptomatic patients contained enteric pathogens . The most frequent isolates were helminths (29.5% of all stools), followed by bacteria (19.2%) and then protozoa (8.9%) . Rates of isolation of diarrhoea-associated pathogens were 29% from diarrhoeal stools and 17% from asymptomatic stools (P = 0.01, chi(2) test) . The association between diarrhoea and infection with bacteria or protozoa was weak and there was no association with helminths.Cryptosporidium parvum infection alone was associated with low CD4 counts . CONCLUSIONS: Diarrhoea was common and most strongly associated with low CD4 counts . Bacteria were frequently found, even in stools from asymptomatic individuals . Over two-thirds of diarrhoeal episodes were undiagnosed, suggesting that unidentified agents or primary HIV enteropathy are important causes of diarrhoea in this population.

Methods, 2002 Aug, 27(4), 324 - 32
Use of fluorescence resonance energy transfer to analyze oligomerization of G-protein-coupled receptors expressed in yeast; Overton MC et al.; Oligomerization or dimerization of G-protein-coupled receptors (GPCRs) has emerged as an important theme in signal transduction . This concept has recently gained widespread interest due to the application of direct and noninvasive biophysical techniques such as fluorescence resonance energy transfer (FRET), which have shown unequivocally that several types of GPCR can form dimers or oligomers in living cells . Current challenges are to determine which GPCRs can self-associate and/or interact with other GPCRs, to define the molecular principles that govern these specific interactions, and to establish which aspects of GPCR function require oligomerization . Although these questions ultimately must be addressed by using GPCRs expressed endogenously in their native cell types, analysis of GPCR oligomerization in heterologous expression systems will be useful to survey which GPCRs can interact, to conduct structure-function studies, and to identify peptides or small molecules that disrupt GPCR oligomerization and function . Here, we describe methods employing scanning fluorometry to detect FRET between GPCRs tagged with enhanced cyan and yellow fluorescent proteins (CFP and YFP) in living yeast cells . This approach provides a powerful means to analyze oligomerization of a variety of GPCRs that can be expressed in yeast, such as adrenergic, adenosine, C5a, muscarinic acetylcholine, vasopressin, opioid, and somatostatin receptors.

Trends Biochem Sci, 2002 Sep, 27(9), 474 - 82
A universal role for MyD88 in TLR/IL-1R-mediated signaling; Janssens S et al.; The MyD88 adapter protein links members of the toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) superfamily to the downstream activation of nuclear factor-kappaB and mitogen-activated protein kinases . Although originally identified as a myeloid-differentiation marker, MyD88 is now known to play an essential role in the innate immune response of insects and mammals . The generation of MyD88-deficient mice, as well as the identification of MyD88-related proteins and regulators of MyD88 signaling, has revealed new and important insights into the function of MyD88.

Trends Endocrinol Metab, 2002 Oct, 13(8), 355 - 60
Aquaporins and disease: lessons from mice to humans; King LS et al.; Recent discovery of a family of water-specific membrane channel proteins, the aquaporins, has provided new insights into the molecular basis of membrane water permeability . Eleven mammalian aquaporins have been identified to date, with homolog present across the spectrum of life, including bacteria, yeast and plants . The distribution of the mammalian aquaporins predicts their participation in a range of pathophysiological events . Empirical evidence of a physiological role for aquaporins is emerging from studies in both mice and humans, and suggests that aquaporins are likely to play significant roles in human pathophysiology.

Biochem J, 2002 Dec 15, 368(Pt 3), 777 - 81
The thylakoid membrane protein ALB3 associates with the cpSecY-translocase in Arabidopsis thaliana; Klostermann E et al.; The integration of light-harvesting chlorophyll proteins (LHCPs) into the thylakoid membrane requires the integral thylakoid membrane protein ALB3, a homologue of the bacterial cytoplasmic membrane protein YidC . In bacteria, YidC is associated with the SecY-translocase and facilitates the integration of Sec-dependent proteins into the plasma membrane . In addition, it is also involved in the insertion of Sec-independent proteins . In the present study we demonstrate, in Arabidopsis thaliana, that most ALB3 is a constituent of an oligomeric complex of approx . 180 kDa . In addition, we detected ALB3 in several higher-molecular-mass complexes (up to 700 kDa) . Furthermore, we show that most ALB3 co-fractionates with cpSecY during gel-filtration analysis and blue native gel electrophoresis, suggesting an association of ALB3 with the cpSecY complex . A direct interaction of ALB3 with the cpSecY complex was demonstrated by co-immunoprecipitation experiments using digitonin-solubilized thylakoid membrane proteins and anti-cpSecY or anti-ALB3 antibodies . This result was further confirmed by electron microscopic co-immunolocalization of ALB3 and cpSecY . In addition, an association of ALB3 with the cpSecY complex was demonstrated directly by cross-linking experiments using the chemical cross-linker disuccinimidyl suberate.

Water Sci Technol, 2002, 46(1-2), 423 - 30
Decay rate variability of active heterotrophic biomass; Lavallee B et al.; Hypotheses of the ASM 1 model state that the specific respiration rate of heterotrophic active biomass is a constant . It thus becomes possible to assess the active heterotrophic biomass decay rate (bH) during starvation . The object of this study is to verify if the specific respiration rate of heterotrophic biomass remains constant throughout starvation, and if it is typical of global metabolic biomass activity, as proposed by the model hypotheses . The decay rate bH was evaluated using respirometric and enzymatic measurements . Measurement of bH through respirometry on various sludges varied between 0.28 and 0.76 d(-1) . According to the enzyme and respirometric measurements carried out, a large portion of this value is related to enzymatic regulation . During starvation, when initial active biomass activity is high, down regulation of the respiratory chain results in a decrease in the specific heterotrophic active biomass respiration rate, thus creating an overevaluation of the decay rate as measured by respirometry . Thus a high decay rate used in the ASM 1 model could eventually lead to a poor forecast of biomass production.

Sci Prog, 2002, 85(Pt 2), 175 - 97
A new method for measuring intramolecular charge transfer; Schmuttenmaer CA; The direct measurement of intramolecular electron transfer through detection of the electromagnetic (EM) waveform that is emitted during this process is reviewed . The waveform is detected in the time-domain via free-space electro-optic sampling and then related to the dynamics of the charge transfer event . Electromagnetic generation from two systems, Betaine-30 in chloroform and DMANS in toluene, are studied to illustrate this technique . A finite-difference time-domain calculation with a time-dependent polarization is used to model the EM generation and propagation through the solution . This method is very general since the movement of charge itself generates the EM waveform, and is sensitive to charge transfer occurring on a 0.1-10 ps timescale . The potential for studying the primary steps of charge transfer in photosynthetic bacteria is also discussed.

Extremophiles, 2002 Aug, 6(4), 309 - 18 Epub 2002 Mar 27.
New isolates and physiological properties of the Aquificales and description of Thermocrinis albus sp . nov; Eder W et al.; The ecology of the Aquificales was studied using a combination of phylogenetic and cultivation approaches . Enrichment cultures were prepared from low-salt and marine samples of geothermally and volcanically heated environments of the United States (Yellowstone National Park), Russia (Kamchatka), Italy, Germany, Djibouti, Iceland, and Africa (Lake Tanganyika) . Isolation of single cells using the selected cell cultivation technique resulted in 15 different pure cultures . Comparisons of their 16S rRNA gene sequences showed that most of the isolates were new representatives of the major lineages of the Aquificaceae, represented by the genera Aquifex, Thermocrinis, Hydrogenobaculum, and Hydrogenobacter . Isolate HI 11/12, which was obtained from whitish streamers in the Hveragerthi area of Iceland, represents a separate branch within the Aquificaceae . The organism grew at salinities up to 0.7% NaCl and at temperatures up to 89 degrees C . Depending on the culture conditions, the organisms occurred as single motile rods, as aggregates, or as long filaments that formed whitish streamer-like cell masses . The novel isolate grew chemolithoautotrophically with hydrogen, sulfur, or thiosulfate as the electron donor under microaerophilic conditions . It represents a second species within the order Thermocrinis, which we name Thermocrinis albus HI 11/12 (DSM 14484, JCM 11386).

Chin Med J (Engl), 2002 Aug, 115(8), 1205 - 8
Adenoviral mediated suicide gene transfer in the treatment of pancreatic cancer; Pan X et al.; OBJECTIVE: To determine the efficacy of adenovirus mediated suicide gene transduction combined with prodrug 5-fluorocytosine (5FC) as a therapeutic protocol for pancreatic cancer . METHODS: Cytosine Deaminase(CD) gene was cloned into pAdTrack-CMV-CD, pAdTrack-CMV-CD and pAdEasy-1 were recombined in bacteria . The newly recombined adenovirus (Ad)-CD containing green fluorescent protein (GFP) were packaged and propagated in 293 cells and purified by cesium chloride gradient centrifugation . Human pancreatic carcinoma cell line-Patu8988 was infected with this virus, then 5FC was added . XTT assay was used to estimate relative numbers of viable cells . In vivo model of pancreatic cancer was established by injecting 1.0 x 10(7) Patu8988 cells subcutaneously in Balb/c nude mice . When tumors were palpable, Ad-CD was injected into each tumor and 5FC was administered . RESULTS: Positive clones were selected using endonuclease to digest the recombinants and the concentration of viral liquids containing the CD gene was 2 x 10(11) pfu /ml . Significant cytotoxic activity as shown for 5FC in the CD gene transduced 8988 cell line, while little effect was found in the nontransduced pancreatic carcinoma cells . Antitumor effect was observed in Patu8988 xenograft nude mice with in situ CD gene transduction . CONCLUSIONS: CD gene mediated by adenovirus has high infectivity and may be useful for gene therapy in pancreatic carcinoma . These data demonstrate the use of an enzyme prodrug strategy in experimental pancreatic cancer.

Hua Xi Kou Qiang Yi Xue Za Zhi, 1998 May, 16(2), 103 - 4, 113
{Comparison of demineralization of different organic acid to enamel}; Liu L et al.; The rates of demineralization of 5 organic acids (mathanoic acid, formic acid, propionic acid, Lactic acid, acetic acid, mixed acid) to the bovine enamel were tested and analysed with the self-made calcium ionselective microelectrodes(Ca(2+)-ISME) basing on a neutral carriers of ETH1001 . The results showed; 1 . The difference between the rates of demineralization of formic acid and lactic acid, formic acid and propionic acid, formic acid and acetic acid, acetic acid and mixed acid, acetic acid and lactic acid, propionic acid and mixed acid, propionic acid and lactic acid, lactic acid and mixed acid were of great significance (P < 0.01); 2 . The rates of demineralization of acetic and mixed acid decreased with time, due to saturation of the solution during demineralization; 3 . Ca(2+)-ISME was of the advantages of simplicity, rapidity, sensitivity and accuracy . The results suggest that the cariogenic potential is related to different acid products of different cariogenic bacteria, and the degree of mineral saturation within solution affects the rate of demineralization.

Pathophysiol Haemost Thromb, 2002, 32 Suppl 1, 1 - 4
Disease transmission by blood products: past, present and future; Murphy WG; Transfusion of blood and blood products has been associated with transmission of infectious agents . However, it is probable that blood products are currently very safe and that pooled virus-inactivated products from remunerated donors are now safer than untreated single voluntary donor components . Although the transmission events of the past and the present are reasonably well understood, reliance on a linear approach to predict safety in the future is open to criticism . Indeed, it was not possible to predict the extent or consequences of the AIDS epidemic or of hepatitis C transmission . Moreover, although variant Creutzfeldt-Jakob disease (vCJD) may not be transmitted to any large extent by transfusion of manufactured blood products, this will be due more to good fortune than good judgement - this agent could have escaped the screening, testing and eradication methods on which current confidence in blood product safety depends . Similarly, the emergence of a highly resistant non-enveloped virus, or even of another previously unrecognised disease-causing agent, could result in new threats from transfusion of blood components and products . The ecology of blood transfusion is exquisitely sensitive to variations in starting conditions, a situation typical of a chaotic rather than a linear system . Seemingly trivial events, often apparently unrelated to blood transfusion, have had enormous consequences in this field . Whatever the events that introduced simian immunodeficiency virus to humans or scrapie to cattle, they were a long way from those involved in the manufacture of blood products . In such a setting, reliance on methods that deal effectively with known threats (such as encapsulated viruses and bacteria) without adequate investigation and management of the intrinsic sensitivity to unpredictable events, leaves open the possibility of further infections emerging in the future . It is this reality that will ultimately result in the eradication of the transfusion of donor-derived blood and blood products in the developed world . In addition, all infections with a long disease-free incubation period in the host that can be transmitted in blood will eventually be over-expressed in groups that are exposed to blood either recreationally or professionally . As in the past, this could have occurred before testing or decontamination processes have been developed for emerging pathogens . Failure to be able to rely on completely risk-free donors, in both the voluntary and non-voluntary sides of the blood industry, continues to offer the potential for the transmission of infectious diseases in the future .

J Alzheimers Dis, 2001 Apr, 3(2), 181 - 190
PAMP and PARL, two novel putative metalloproteases interacting with the COOH-terminus of Presenilin-1 and -2; Pellegrini L et al.; The familial Alzheimer's disease gene products, presenilin-1 and presenilin-2 (PS1 and PS2), are involved in amyloid beta-protein precursor processing (AbetaPP), Notch receptor signaling, and programmed cell death . However, the molecular mechanisms by which presenilins regulate these processes remain unknown . Clues about the function of a protein can be obtained by seeing whether it interacts with another protein of known function . Using the yeast two-hybrid system, we identified two proteins that interact and colocalize with the presenilins . One of these newly detected presenilin-interacting proteins belongs to the FtsH family of ATP-dependent proteases, and the other one belongs to Rhomboid superfamily of membrane proteins that are highly conserved in eukaryotes, archaea and bacteria . Based on the pattern of amino acid residues conservation in the Rhomboid superfamily, we hypothesize that these proteins possess a metal-dependent enzymatic, possibly protease activity . The two putative proteases interacting with presenilins could mediate specific proteolysis of membrane proteins and contribute to the network of interactions in which presenilins are involved.

Biochim Biophys Acta, 2002 Sep 13, 1577(2), 175 - 90
Elongation by RNA polymerase II: structure-function relationship; Gnatt A; RNA polymerase II is the eukaryotic enzyme that transcribes all the mRNA in the cell . Complex mechanisms of transcription and its regulation underlie basic functions including differentiation and morphogenesis . Recent evidence indicates the process of RNA chain elongation as a key step in transcription control . Elongation was therefore expected and found to be linked to human diseases . For these reasons, major efforts in determining the structures of RNA polymerases from yeast and bacteria, at rest and as active enzymes, were undertaken . These studies have revealed much information regarding the processes involved in transcription . Eukaryotic RNA polymerases and their homologous bacterial counterparts are flexible enzymes with domains that separate DNA and RNA, prevent the escape of nucleic acids during transcription, allow for extended pausing or "arrest" during elongation, allow for translocation of the DNA and more . Structural studies of RNA polymerases are described below within the context of the process of transcription elongation, its regulation and function.

J Vet Pharmacol Ther, 2002 Aug, 25(4), 279 - 84
The effect of josamycine on the control of ileitis in weaned piglets under field conditions; Kyriakis SC et al.; The aim of this trial was to evaluate the effect of in-feed josamycine on the control of ileitis in weaned piglets . On a farm with a previous history of ileitis outbreaks, 288 piglets at weaning age (25 +/- 2 days old) were allocated into three experimental groups, each group comprising of four pens with 24 piglets in each pen . Group one (T1) served the trial as negative control group (unmedicated), group T2 was administered josamycine at 36 mg/kg of feed and group T3 was administered josamycine at 50 mg/kg of feed . Treatments lasted for 14 days followed by an observation period of 28 days . Administration of josamycine at both inclusion levels tested had a beneficial effect compared with the negative control group, by the reduction of prevalence of diarrhoea, the enhancement of growth performance and the reduction of prevalence of Lawsonia intracellularis in the intestine, as determined either by the PCR method or by specific histopathological examinations . The beneficial effect of josamycine was more pronounced at the inclusion level of 50 mg/kg of feed.

J Vet Pharmacol Ther, 2002 Aug, 25(4), 273 - 7
Distribution of orally administered trimethoprim and sulfadiazine into noninfected subcutaneous tissue chambers in adult ponies; van Duijkeren E et al.; The distribution of trimethoprim (TMP) and sulfadiazine (SDZ) into subcutaneously implanted noninfected tissue chambers was studied in healthy adult ponies . Six ponies were given an oral TMP/SDZ paste formulation at a dose of 5 mg/kg TMP and 25 mg/kg SDZ at 12 h intervals for 2 days in order to reach steady-state concentrations . Plasma concentrations and tissue chamber fluid (TCF) concentrations of both drugs were measured at regular intervals during a period commencing 24 h after the last oral administration . The peak concentration of TMP (mean +/- SD) was 2.92 +/- 0.86 microg/mL for plasma and 1.09 +/- 0.25 microg/mL for TCF . For SDZ, the mean peak concentration was 40.20 +/- 14.74 microg/mL for plasma and 23.48 +/- 5.84 microg/mL for TCF . TMP peak concentrations in plasma were reached at 3.17 +/- 03.48 h and those in TCF at 7.33 +/- 03.72 h . SDZ peak concentrations in plasma were reached at 1.83 +/- 02.04 h and those in TCF at 8.00 +/- 03.10 h . Concentrations of TMP and SDZ in TCF remained above the generally accepted breakpoint for susceptibility (0.5/9.5 for the TMP/SDZ combination) for 12 h . Therefore, in ponies oral administration of TMP/SDZ at a dose rate of 30 mg/kg given twice daily in the form of a paste should be appropriate for effective treatment of infections caused by susceptible bacteria.

Transgenic Res, 2002 Aug, 11(4), 373 - 9
Overexpression of the wheat FK506-binding protein 73 (FKBP73) and the heat-induced wheat FKBP77 in transgenic wheat reveals different functions of the two isoforms; Kurek I et al.; The FK506-binding proteins (FKBPs) belong to the peptidyl prolyl cis-trans isomerase (PPIase) family, and catalyse the rotation of the peptide bond preceding a proline . They are conserved in organisms from bacteria to man . In order to understand the function of plant FKBP isoforms, we have produced transgenic wheat plants overexpressing each of the two wheat FKBPs: wFKBP73 (which is expressed in young vegetative and reproductive tissues under normal growth conditions) and wFKBP77 (which is induced by heat stress) . Transgenic lines overexpressing wFKBP77 at 25 degrees C showed major morphological abnormalities, specifically relating to height, leaf shape, spike morphology and sterility . In these plants, the levels of hsp90 mRNA were over two fold higher than in controls, indicating a common regulatory pathway shared between wFKBP77 and Hsp90 . Transgenic lines overexpressing wFKBP73 showed normal vegetative morphology, but the grain weight and composition was altered, corresponding to changes in amylase activity during seed development.

J Environ Sci (China), 2002 Jul, 14(3), 388 - 92
Photo-assisted fenton oxidation of refractory organics in UASB-pretreated leachate; Lau IW et al.; Nearly 91% of organic pollutants in Hong Kong leachate could be effectively removed by the UASB (upflow anaerobic sludge blanket) process followed by the fenton coagulation . The COD (chemical oxygen demand) of leachate was lowered from an average of 5620 mg/L to 1910 mg/L after the UASB treatment at 37 degrees C, and was further lowered to 513 mg/L after fenton coagulation . The remaining refractory residues could be further removed by photochemical oxidation with the addition of H2O2 . The BOD/COD ratio was greatly increased from 0.062 to 0.142, indicating the biodegradability of organic residues was improved . The photochemical oxidation for the fenton-coagulation supernatant was most effective at pH 3-4, with the addition of 800 mg/L of H2O2, and UV radiation time of 30 minutes . The final effluent contained only 148 mg/L of COD, 21 mg/L of BOD (biochemical oxygen demand) and 56 mg/L of TOC (total organic carbon).

J Periodontol, 2002 Aug, 73(8), 886 - 91
Eikenella corrodens in subgingival plaque: relationship to age and periodontal condition; Suda R et al.; BACKGROUND: The purpose of this study was to determine the prevalence and distribution of Eikenella corrodens (E . corrodens) in subgingival plaque in different age and periodontitis groups and to examine whether its presence is related to periodontal diseases . METHODS: A total of 273 subgingival plaque samples from 213 periodontitis patients and 60 healthy subjects were assessed . Smears from each plaque sample were made and E . corrodens was detected by means of indirect immunofluorescent technique . Mean percentage of E . corrodens per total bacteria (distribution) was calculated in each sample . The prevalence (% of positive samples) and distribution of E . corrodens were statistically analyzed based on age or diagnosis by means of Fisher's exact test and analysis of variance (ANOVA) . RESULTS: Prevalence of E . corrodens decreased by age in the healthy control group; however, prevalence did not change in periodontitis groups . Distribution of E . corrodens was highest in juvenile periodontitis (JP) (2.3 +/- 1.5%) followed by post-JP (1.7 +/- 2.1%), prepubertal periodontitis (1.4 +/- 1.1%), rapidly progressive periodontitis (0.8 +/- 0.7%), adult periodontitis (0.7 +/- 0.6%), and healthy subjects (0.3 +/- 0.3%) (ANOVA, P<0.0001) . The <20-year-old age group with periodontitis showed the highest distribution of E . corrodens (2.2 +/- 1.6%) compared to the older age groups who were either healthy or had periodontitis (ANOVA, P<0.0001) . CONCLUSIONS: Since the distribution of E . corrodens is significantly higher in JP, post-JP, and PP, E . corrodens might play an important role in the occurrence or progression of periodontitis in young patients.

J Periodontol, 2002 Aug, 73(8), 877 - 85
Frequency of reactivity for Porphyromonas gingivalis and Prevotella spp . in supra- and subgingival plaques, and periodontal clinical parameters according to subject age; Tanaka S et al.; BACKGROUND: The present study was conducted to assess the association between selected clinical parameters and the distribution of Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Prevotella nigrescens (Pn), and Prevotella melaninogenica (Pm) in supra- and subgingival plaque samples measured by an immunoslot blot assay (IBA) using their monoclonal antibodies . METHODS: Plaque samples from 299 patients aged 6 to 69 randomly chosen from a group of dental outpatients were examined . Plaque index, gingival index, and probing depths were evaluated according to the criteria of positive (cell number > or = 10(6)) or negative (<106) reactivity to the 4 different monoclonal antibodies . RESULTS: An increase in probing depth in subjects exhibiting either a positive or negative reaction for the 4 test bacteria was associated with increasing age . Comparing bacteria-positive subgingival plaque samples to their corresponding bacteria-negative counterparts, we found an increased plaque index in children positive for any of the 4 bacteria; in addition, that for Pg and Pi was increased in subjects 40 to 49 years old . The gingival index increased with increasing amount of Pi and Pn, but not with Pg and Pm in those 20 to 29 years of age . The frequency of Pg reactivity in subgingival plaque was markedly enhanced in subjects older than 30 to 39 years of age, and was significantly higher than that in supragingival plaque . The frequency of Pi and Pn reactivity was significantly increased in adults aged 20 to 29 and plateaued at older ages . The frequency of Pm reactivity was relatively low and independent of subject age . CONCLUSIONS: The increase in probing depth with increasing age was not affected by the occurrence of periodontopathic bacteria . The high rate of occurrence of Pg, together with Pi and Pn, in subgingival plaque of the adult age groups was suggested to be associated with the high frequency of periodontal disease in the older age groups (above 30 to 49 years of age) . The IBA appears to be useful for the efficient and rapid detection of periodontopathic bacteria.

Poult Sci, 2002 Aug, 81(8), 1132 - 5
Reduction of eggshell aerobic plate counts by ultraviolet irradiation; Chavez C et al.; The effects of 254 nm ultraviolet light (UV) radiation on aerobic plate count (APC) of egg shells were investigated . In the first experiment, eggs were exposed to UV treatment (7.35 mW/cm2) for 0, 15, 30, and 60 s . Three eggs from each treatment were aseptically collected and placed into sterile plastic bags containing 50 mL of sterile phosphate-buffered solution . Serial dilutions of the phosphate-buffered solution were plated on aerobic plate count agar and incubated at 37 C for 48 h . Exposure of eggshells to 30 and 60 s UV significantly reduced aerobic plate counts compared to untreated eggs . Exposure to 60 s of UV resulted in a 2 to 3 log10 cfu/egg APC reduction and reduced counts below detectable levels . In the second experiment, UV lights were placed in a chamber equipped with a commercial-style egg conveyor . A UV treatment of 7.5 mW/cm2 and time intervals of 0, 12, 36, and 48 s were used . Three eggs were placed consecutively on the conveyor and passed through the chamber . The center egg was selected for APC evaluation . Sample size, dilution, plating, and incubation procedures were used as described for the first experiment . A significant 1 to 2 log10 reduction in colony-forming units per egg between the eggs treated 48 s to the untreated eggs was detected . The results of these studies show that UV light treatment at high intensities and low time intervals has the potential to reduce aerobic plate counts of eggshells.

Comp Med, 2002 Aug, 52(4), 332 - 41
Adoptive transfer of BALb/c mouse splenocytes reduces lesion severity and induces intestinal pathophysiologic changes in the Mycobacterium avium Subspecies paratuberculosis beige/scid mouse model; Mutwiri GK et al.; Successful immune reconstitution would enhance resistance of beige/scid mice to chronic infection with Mycobacterium avium subspecies paratuberculosis, but may cause damage to intestinal tissue . Therefore, we investigated the effect of adoptive transfer of BALB/c mouse splenocytes on lesion severity and intestinal physiology in beige/scid mice infected with M . paratuberculosis . Mice were inoculated intraperitoneally (i.p.) with M . paratuberculosis, and two weeks later were inoculated i.p . with viable spleen cells from immune-competent BALB/c mice . Mice were necropsied 12 weeks after infection when engraftment of lymphocytes, clinical disease, pathologic lesions, and intestinal electrophysiologic parameters were evaluated . Lymphocytes were rare in control beige/scid mice not inoculated with spleen cells . In contrast, high numbers of CD4+, CD8+, and B220+ lymphocytes were detected in the spleen of all beige/scid mice (n = 24) inoculated with spleen cells, indicating that adoptive transfer resulted in successful engraftment of donor lymphocytes (immune reconstitution) . Immune reconstitution of M . paratuberculosis-infected beige/ scid mice significantly reduced the severity of clinical disease and pathologic lesions, and numbers of bacteria in the liver . However, intestinal electrophysiologic parameters studied in vitro indicated that intestinal tissues from reconstituted beige/scid mice had reduced short-circuit current responses (due to reduced ion secretion) following electrical, glucose, and forskolin stimulation . These abnormal responses suggested that neural or epithelial cells in the intestine were damaged . We conclude that successful immune reconstitution of beige/scid mice enhance their resistance to M . paratuberculosis infection, but may cause pathophysiologic changes associated with intestinal inflammation.

Environ Mol Mutagen, 2002, 40(1), 41 - 9
Photoclastogenicity-an improved protocol, its validation, and investigation of the photogenotoxicity of DMBA; Murli H et al.; An improved protocol was developed to detect light-induced clastogenic photoproducts in Chinese hamster ovary (CHO) cells . Dishes (60 mm) containing cells and the test material or vehicle control in 3 mL of phosphate-buffered saline were exposed to light using a SUNTEST CPS solar simulation unit . Importantly, cells were exposed at about 25 cm from the light source, thereby allowing a short exposure time of 2 min . With this exposure the assay was conducted with lids removed during the UV exposure with minimal risk of contamination . After preliminary experiments an exposure of 165.6 mJ/cm(2) UVA: 17.0 mJ/cm(2) UVB was selected for treatments with the different phototoxins . Under these exposure conditions about 10-15% aberrant cells were induced in vehicle control cultures with no or minimal cytotoxicity . The well-known photoclastogens 8-methoxypsoralen (8-MOP) and chlorpromazine (CLZ) were tested . In agreement with published data, 8-MOP and CLZ were clastogenic (lowest observed effect level, LOEL, was 0.0159 microg/mL and 1.03 microg/mL, respectively) . In the absence of UV, 8-MOP was clastogenic at a much higher concentration (LOEL 251 microg/mL without UV vs . 0.0159 microg/mL with UV) while CLZ was negative up to a toxic concentration of 35 microg/mL . 7,12-Dimethylbenz{a}anthracene (DMBA), which is photomutagenic in bacteria, was clastogenic at > or =0.005 microg/mL with UV light (without S9) and at > or =2.53 microg/mL with S9 (without UV light) . These results demonstrate the utility of the protocol for the detection of photoclastogenicity and expand the characterization of DMBA's photogenotoxic activity .

Arch Insect Biochem Physiol, 2002 Sep, 51(1), 46 - 54
Eicosanoids mediate Manduca sexta cellular response to the fungal pathogen Beauveria bassiana: a role for the lipoxygenase pathway; Lord JC et al.; Many studies have documented the involvement of eicosanoids in insect cellular immune responses to bacteria . The use of the fungal pathogen Beauveria bassiana as a nodulation elicitor, with inhibition of phospholipase A(2) by dexamethasone, extends the principle to fungi . This study also provides the first evidence of involvement of the lipoxygenase (LOX) pathway rather than the cyclooxygenase (COX) pathway in synthesis of the nodulation mediating eicosanoid(s) . The LOX product, 5(S)-hydroperoxyeicosa-6E,8Z,11Z,14Z-tetraenoic acid (5-HPETE), substantially reversed nodulation inhibition caused by dexamethasone and the LOX inhibitors, caffeic acid and esculetin . The COX product, prostaglandin H(2) (PGH(2)), did not reverse the nodulation inhibition by dexamethasone or the COX inhibitor, ibuprofen . None of the inhibitors tested had a significant effect on the phagocytosis of B . bassiana blastospores in vitro . Hemocyte phenoloxidase activity was reduced by dexamethasone, esculetin, and the COX inhibitor, indomethacin . The rescue candidates 5-HPETE and PGH(2) did not reverse the inhibition.

Arch Insect Biochem Physiol, 2002 Sep, 51(1), 13 - 26
Co-development of Encarsia formosa (Hymenoptera: Aphelinidae) and the greenhouse whitefly, Trialeurodes vaporariorum (Homoptera: Aleyrodidae): a histological examination; Blackburn MB et al.; Using histological techniques, we have simultaneously examined the co-development of the Aphelinid parasitoid Encarsia formosa and its host the greenhouse whitefly, Trialeurodes vaporariorum . Previously we have determined that regardless of the whitefly instar parasitized, parasitoid larvae would not molt to their final instar until the whitefly reaches its maximum dimensions . In unparasitized T . vaporariorum, this point in development corresponds to the initiation of the adult molt . In part, this study was conducted to determine the developmental state of parasitized whiteflies at the time they achieve their maximum dimensions . It was found that parasitized final instar T . vaporariorum do, in fact, undergo a final molt and that E . formosa larvae will not molt to their final instar until this has occurred . The timing of the final whitefly molt appears unaffected by parasitization . The commonly observed melanization of parasitized whiteflies appears to be a consequence of this molt . In addition, we have discovered that the adult wasp oviposits within the ventral ganglion of the whitefly, and that major organ systems of the whitefly persist very late into parasitoid development . We also report the presence of possible endosymbiotic bacteria residing in the fatbody of E . formosa.

Biomed Chromatogr, 2002 Aug, 16(5), 327 - 31
Capillary electrophoresis of Cr(VI) reducer Arthrobacter oxydans; Tsibakhashvili NY et al.; Rapid and effective separation of bacteria Arthrobacter oxydans was performed using capillary electrophoresis . For optimal separation of bacteria the influence of buffer concentration, pH and applied voltage were studied . It was found that the most appropriate conditions for electrophoretic mobility measurements are as follows: applied voltage 6-14 kV; buffer concentration 5-10 mM pH 6-8 . At the stationary phase of growth there are always two main heterogeneous peaks . They are connected with the morphology of bacteria as well as with cell aggregation . The heterogeneity of samples may be explained by surface modifications of bacterial cells .

Microb Ecol, 2002 Oct, 44(3), 217 - 23 Epub 2002 Sep 06.
Dissolved primary production and the strength of phytoplankton- bacterioplankton coupling in contrasting marine regions; Moran XA et al.; We analyzed the strength of phytoplankton-bacterioplankton coupling by comparing the rate of particulate (PPP) and dissolved primary production (DPP) with bacterial carbon demand (BCD) in four contrasting marine regions: offshore and coastal waters of the Southern Ocean, a coastal area of the NE Atlantic, and a coastal-offshore transect in the NW Mediterranean . We measured bacterial heterotrophic production (BHP) and estimated BCD from a literature model . Average phytoplanktonic percent extracellular release {PER = DPP/(DPP + PPP)} was 18-20% in the Antarctic (offshore and coastal, respectively), 16% in the NW Mediterranean, and 7% in the NE Atlantic . A significant inverse relationship was found between PER and total system productivity with pooled data . On average BHP amounted to <5% of total primary production in all regions . However, the strength of phytoplankton-bacterioplankton coupling, estimated as the potential importance of DPP in meeting BCD, differed greatly in the four regions . DPP was highly correlated to BCD in offshore Antarctic waters and was sufficient to meet BCD . In contrast, BCD exceeded DPP and bore no significant relationship in the remaining regions . The data suggest that a strong dependence of bacteria on algal extracellular production is only expected in open-ocean environments isolated from coastal inputs of DOC.

Rheumatology (Oxford), 2002 Sep, 41(9), 1017 - 20
Importance of species-specific antigens in the serodiagnosis of Chlamydia trachomatis reactive arthritis; Bas S et al.; OBJECTIVES: To determine the most sensitive and specific method of anti-Chlamydia antibody measurement for the serodiagnosis of Chlamydia trachomatis reactive arthritis . METHODS: Immunoblotting, enzyme-linked immunosorbent assays using six synthetic peptides or recombinant antigens and a microimmunofluorescence test were used to determine the presence of IgG, IgM and IgA in serum samples from 17 patients with C . trachomatis reactive arthritis . Twenty patients with other inflammatory arthropathies without evidence of urogenital C . trachomatis infection were used as controls . RESULTS: The best association of sensitivity (76%) and specificity (85%) was obtained when IgG and/or IgA reactivity to two species-specific antigens was determined . These antigens were synthetic peptides, derived from species-specific epitopes in the variable domain IV of the major outer membrane protein (MOMP) (Labsystems, Finland) and recombinant polypeptide encoded by open reading frame 3 of the plasmid (pgp3) . CONCLUSIONS: IgG and/or IgA anti-MOMP-derived peptides and anti-pgp3 could be useful for the diagnosis of probable C . trachomatis reactive arthritis.

Math Biosci, 2002 Sep-Oct, 179(2), 183 - 206
Plasmid-bearing, plasmid-free organisms competing for two complementary nutrients in a chemostat; Hsu SB et al.; A model of competition for two complementary nutrients between plasmid-bearing and plasmid-free organisms in a chemostat is proposed . A rigorous mathematical analysis of the global asymptotic behavior of the model is presented . The work extends the model of competition for a single-limited nutrient studied by Stephanopoulos and Lapidus {Chem . Engng . Sci . 443 (1988) 49} and Hsu, Waltman and Wolkowicz {J . Math . Biol . 32 (1994) 731}.

Med Hypotheses, 2002 Aug, 59(2), 159 - 63
Impaired inactivation of digestive proteases by deconjugated bilirubin: the possible mechanism for inflammatory bowel disease; Qin XF; Inflammatory bowel disease refers to ulcerative colitis and Crohn's disease, two gut diseases with unknown causes . The dramatic increase in the last half century and the big difference in incidence for people with the same ethnic background but living in different areas strongly suggested that environmental factors played the dominant role for these diseases . The similarity in many aspects for these two diseases suggested a common causative factor . Here I suggest the impaired inactivation of digestive proteases by deconjugated bilirubin, as the result of the inhibition of bilirubin deconjugation enzyme, beta-glucuronidase, originated from the luminal bacteria and mucosa of the gut, to be a possible mechanism for both ulcerative colitis and Crohn's diseases . I also provide evidence to suggest that saccharin could be the causative or one of the most important risk factors for inflammatory bowel disease as for its inhibition on beta-glucuronidase in the intestine.

Med Hypotheses, 2002 Oct, 59(4), 411 - 5
Rheumatoid arthritis is auto-immunoreaction to collagen II in cartilage happened in synovial tissue; Wang J et al.; Rheumatoid arthritis is complex and not clear on the mechanism of pathogenesis . On the basis of analysis of the symptom and pathology of rheumatoid arthritis patients, we raised a new hypothesis . The content of the hypothesis is as follows: (A) Collagen II or collagen II-Iike substance in human cartilage is the cross-autoantigen of some infecting virus or bacteria because of the structure's similarity . (B) The inflammation in synovial tissue is auto-immunoreaction to collagen II in cartilage . (C) The proliferation and attachment of synovial tissue to the surface of cartilage is due to the chemotaxis of collagen II in cartilage for the immunocytes in synovial tissue . (D) The collagenase secreted from synovial cells and immunocytes are the direct elements in the destruction of cartilage . The fallen collagen II from cartilage is one of the most important inducer on the synovial cells and immunocytes for the production of collagenase.

Vet Parasitol, 2002 Sep 10, 108(2), 153 - 61
Molecular phylogenetic analysis of Onchocerca lupi and its Wolbachia endosymbiont; Egyed Z et al.; The morphology of Onchocerca lupi, responsible for canine ocular onchocercosis, is unique within the genus . Earlier analyses of the 5S ribosomal RNA gene spacer region sequence of the parasite and the 16S ribosomal RNA gene sequence of its Wolbachia endosymbiotic bacteria (Rickettsiales) supported the morphological and biological arguments that O . lupi is a distinct species . However, the exact phylogenetic position of O . lupi and its endosymbiont could not be unambiguously determined . Herein we report analyses based on the mitochondrial cytochrome oxidase I (COI) gene of the filarial species and the Wolbachia surface protein (wsp) and the bacterial cell-cycle ftsZ genes of their wolbachiae . Our results indicate that O . lupi separated from other Onchocerca spp . early in evolution . This is in line with the previous morphological analysis demonstrating that O . lupi is an atypical Onchocerca species showing both primitive and evolved characters . The phylogenetic trees generated for the COI sequences of filariae and the wsp and ftsZ sequences of their wolbachiae were congruent with each other, which supports the hypothesis that nematodes and their Wolbachia endobacteria share a long co-evolutionary history.

Biochem Biophys Res Commun, 2002 Sep 6, 296(5), 1366 - 71
Acidophilic character of yeast PID261/BUD32, a putative ancestor of eukaryotic protein kinases; Facchin S et al.; Yeast piD261/Bud32 and its homologues are present in eukaryotes and in archaea but not in bacteria and are believed to make up a primordial branch of the eukaryotic protein kinase superfamily . Here, we show that, at variance with the majority of Ser/Thr protein kinases which recognize phosphoacceptor sites specified by basic and/or proline residues, piD261 phosphorylates in vitro a number of acidic proteins and peptides, and it recognizes seryl residues specified by carboxylic side chains . These data suggest that recognition of acidic sites might have been a primordial trait of protein kinases, which was modified during evolution to cope with the increasing complexity of protein phosphorylation in eukaryotes.

Mol Ecol, 2002 Sep, 11(9), 1815 - 29
The incidence and diversity of Wolbachia in gallwasps (Hymenoptera; Cynipidae) on oak; Rokas A et al.; Wolbachia bacteria infect approximately 20% of all insect species, and cause a range of alterations to host reproduction, including imposition of thelytoky . The incidence and phenotypic impact of Wolbachia remains to be established in many insect taxa, and considerable research effort is currently focused on its association with particular reproductive modes and the relative importance of the various pathways via which infection occurs . Gallwasps represent an attractive system for addressing these issues for two reasons . First, they show a diversity of reproductive modes (including arrhenotoky, thelytoky and cyclical parthenogenesis) in which the impact of Wolbachia infection can be examined . Second, they occupy two intimately linked trophic niches (gall-inducers and inquilines) between which there is potential for the horizontal exchange of Wolbachia infection . In the arrhenotokous gallwasp lineages screened to date (the herb-galling 'Aylacini' and the rose-galling Diplolepidini), Wolbachia infection always induces thelytoky . The impact of Wolbachia in other arrhenotokous clades, and in the cyclically parthenogenetic clades remains unknown . Here we use polymerase chain reaction (PCR) screening and sequence data for two Wolbachia genes (wsp and ftsZ) to examine the prevalence and incidence of Wolbachia infection in 64 species (a total of 609 individuals) in two further tribes: the arrhenotokous inquilines (tribe Synergini), and the cyclically parthenogenetic oak gallwasps (tribe Cynipini) . We ask: (i) whether Wolbachia infection has any apparent impact on host reproduction in the two tribes and (ii) whether there is any correlation between Wolbachia infection and the apparent lack of an arrhenotokous generation in many oak gallwasp life cycles . We show: (i) that Wolbachia infection is rare in the Cynipini . Infected species show no deviation from cyclical parthenogenesis, and infection is no more common in species known only from a thelytokous generation; (ii) that there is a higher incidence of infection within the arrhenotokous inquilines, and generally in gallwasp tribes without cyclical parthenogensis; (iii) all Wolbachia-positive inquiline species are known to possess males, implying either that Wolbachia infection does not result in loss of sex in this tribe or, more probably, that (as for some rose gallwasps) Wolbachia infection leads to loss of sex in specific populations; and (iv) although we find some inquilines and gall inducers to be infected with Wolbachia having the same wsp sequence, these hosts are not members of the same gall communities, arguing against frequent horizontal transmission between these two trophic groups . We suggest that exchange may be mediated by the generalist parasitoids common in oak galls.

J Agric Food Chem, 2002 Sep 11, 50(19), 5490 - 5
Antioxidant effects of isorhamnetin 3,7-di-O-beta-D-glucopyranoside isolated from mustard leaf (Brassica juncea) in rats with streptozotocin-induced diabetes; Yokozawa T et al.; To investigate the effects of isorhamnetin 3,7-di-O-beta-D-glucopyranoside (isorhamnetin diglucoside), a major flavonoid compound of mustard leaf, on oxidative stress due to diabetes mellitus, in vivo and in vitro studies were carried out . Oral administration of isorhamnetin diglucoside (10 or 20 mg/kg of body weight/day for 10 days) to rats with streptozotocin-induced diabetes significantly reduced serum levels of glucose and 5-(hydroxymethyl)furfural (5-HMF), which is glycosylated with hemoglobin and is an indicator of oxidative stress . After intraperitoneal administration, isorhamnetin diglucoside did not show these activities . In addition, after oral administration, the thiobarbituric acid-reactive substance levels of serum, and liver and kidney mitochondria declined significantly compared with the control group in a dose-dependent manner, whereas after intraperitoneal administration these levels fell only slightly . On the basis of the oral and intraperitoneal results, it was hypothesized that isorhamnetin diglucoside was converted to its metabolite in vivo, and its conversion to its aglycone, isorhamnetin, by beta-glucosidase was confirmed; isorhamnetin acted as an antioxidant . Moreover, it was observed that isorhamnetin diglucoside had no effect on the 1,1-diphenyl-2-picrylhydrazyl radical, whereas isorhamnetin showed a potent antioxidant effect in vitro . In addition, intraperitoneal administration of isorhamnetin reduced serum glucose and 5-HMF levels . Furthermore, lipid peroxidation in blood, liver, and kidney associated with diabetes mellitus declined after the administration of isorhamnetin . These results suggest that isorhamnetin diglucoside is metabolized in vivo by intestinal bacteria to isorhamnetin and that isorhamnetin plays an important role as an antioxidant.

Clin Diagn Lab Immunol, 2002 Sep, 9(5), 1132 - 6
Determination of the nucleotide sequences of heat shock operon groESL and the citrate synthase gene (gltA) of Anaplasma (Ehrlichia) platys for phylogenetic and diagnostic studies; Inokuma H et al.; The 1,670-bp nucleotide sequence of the heat shock operon groESL and the 1,236-bp sequence of the citrate synthase gene (gltA) of Anaplasma (Ehrlichia) platys were determined . The topology of the groEL- and gltA-based phylogenetic tree was similar to that derived from 16S rRNA gene analyses with distances . Both groESL- and gltA-based PCRs specific to A . platys were also developed based upon the alignment data.

Arch Environ Contam Toxicol, 2002 Oct, 43(3), 270 - 6
Nitrates/nitrites alter human lymphocyte proliferation and cytokine production; Ustyugova IV et al.; Nitrate from drinking water is converted in the body to nitrite by bacteria in the gut . This project examined effects of nitrate/nitrite on immune functions, i.e., human lymphocyte proliferation and cytokine production . Nitrate had no effect on lymphocyte growth, but nitrite decreased proliferation . Neither inhibited fibroblast growth . In 1/3 to 2/3 of the subjects tested, sodium nitrate or nitrite decreased production of Th1 cytokines (interleukin-2, interferon-gamma, and tumor necrosis factor-beta) . Nitrate and nitrite either increased or had no effect on the production of the Th2 cytokine interleukin-10 . A Th1 immune response is associated with resistance to a variety of infectious diseases; a Th2 response is associated with disease susceptibility . Because nitrate/nitrite shifted the balance from a Th1 to a Th2 response in some individuals, exposure to these compounds may decrease these persons' responsiveness to infectious diseases . The levels of nitrate used in this study are relevant to human health because they are present in the liquid portion (nonbreastfed) of some 2-month-old infants' diets in rural Romania.

Nucleic Acids Res . 2002 Sep 1;30(17):e90.
Cre recombinase-mediated inversion using lox66 and lox71: method to introduce conditional point mutations into the CREB-binding protein; Zhang Z et al.; CREB-binding protein (CBP) is a multifunctional cofactor implicated in many intracellular signal transduction pathways . We aimed to investigate the involvement of CBP in the cAMP response element-binding protein (CREB)-mediated pathway . The point mutation Tyr658Ala in the CREB-binding domain (CBD) was shown to abolish the binding activity of CBP to phospho-CREB, the activated form of CREB . By using a mutant Cre/loxP recombination system, this point mutation was aimed to be generated in the mouse genome in a tissue- and time-specific manner . A targeting construct in which CBD exon 5 and inverted exon 5* containing the point mutation flanked by two mutant loxP sites (lox66 and lox71) oriented in a head-to-head position was generated . When Cre recombinase is present, the DNA flanked by the two mutant loxP sites is inverted, forming one loxP and one double mutated loxP site . As the double mutated loxP site shows low affinity for Cre recombinase, the favorable reaction leads to a product where the mutated exon 5* is placed into the position to be correctly transcribed and spliced . Inversion was observed to be complete in both bacteria and mouse embryonic stem cells . Our results indicate that this Cre- mediated inversion method is a valuable tool to introduce point mutations in the mouse genome in a regulatable manner.

J Clin Microbiol, 2002 Sep, 40(9), 3463 - 9
Molecular typing of papillomatous digital dermatitis-associated Treponema isolates based on analysis of 16S-23S ribosomal DNA intergenic spacer regions; Stamm LV et al.; Papillomatous digital dermatitis (PDD), an emerging infectious disease of cattle, is characterized by painful, ulcerative foot lesions . The detection of high numbers of invasive spirochetes in PDD lesions suggests an important role for these organisms in the pathogenesis of PDD . PDD-associated spirochetes have phenotypic characteristics consistent with members of the genus TREPONEMA: Partial 16S ribosomal DNA (rDNA) sequence analysis of clonal isolates from California cattle showed that they comprise three phylotypes which cluster closely with human-associated Treponema spp . of the oral cavity (T . denticola and T . medium/T . vincentii) or genital area (T . phagedenis) . The goal of our study was to apply 16S-23S rDNA intergenic spacer region (ISR) sequence analysis to the molecular typing of U.S . PDD-associated Treponema isolates . This methodology has potentially greater discriminatory power for differentiation of closely related bacteria than 16S rDNA analysis . We PCR amplified, cloned, and sequenced the ISRs from six California PDD-associated Treponema isolates and, for comparative purposes, one strain each of T . denticola, T . medium, T . vincentii, and T . phagedenis . Two ISRs that varied in length and composition were present in all the PDD-associated Treponema isolates and in T . denticola, T . medium, and T . phagedenis . ISR1 contained a tRNA(Ala) gene, while ISR2 contained a tRNA(Ile) gene . Only a single ISR (ISR1) was identified in T . vincentii . Comparative analyses of the ISR1 and ISR2 sequences indicated that the California PDD-associated Treponema isolates comprised three phylotypes, in agreement with the results of 16S rDNA analysis . PCR amplification of the 16S-tRNA(Ile) region of ISR2 permitted rapid phylotyping of California and Iowa PDD-associated Treponema isolates based on product length polymorphisms.

J Clin Microbiol, 2002 Sep, 40(9), 3364 - 73
Rapid-cycle PCR and fluorimetry for detection of mycobacteria; Lachnik J et al.; In this study we used LightCycler PCR amplification and product detection by fluorescence resonance energy transfer probes to identify mycobacteria and differentiate between Mycobacterium tuberculosis complex, Mycobacterium avium, and other nontuberculous mycobacteria . Targeting the 16S rRNA gene, three different probes specific for mycobacteria, M . tuberculosis complex, and M . avium were constructed . As few as five genome copies of target nucleic acid were detected by the probes, illustrating the high sensitivity of the system . All 33 mycobacterial species tested but none of the closely related actinomycetes and other bacteria produced a specific fluorescence signal . A specificity of 100% was also demonstrated for the M . tuberculosis complex-specific probe and the M . avium-specific probe . Within 45 min, the LightCycler method correctly detected mycobacteria and specifically identified M . tuberculosis complex and M . avium without any post-PCR sample manipulation . In view of future clinical studies, we also constructed and tested an internal control which could be used to assure successful amplification and detection of mycobacteria . Monitoring of PCR inhibition will be essential for evaluation of this system for direct detection of mycobacteria in clinical specimens . Finally, we tested our system on sputum seeded with mycobacteria and were able to detect as few as 10 organisms . At present, this system is the fastest available method for identification and differentiation of mycobacteria from culture-positive specimens and offers an excellent alternative to previously established nucleic acid amplification-based techniques for the diagnostic mycobacterial laboratory.

J Clin Microbiol, 2002 Sep, 40(9), 3281 - 5
Mycobacterium microti infection (vole tuberculosis) in wild rodent populations; Cavanagh R et al.; Mycobacterium microti (vole tuberculosis) infections in small wild mammals were first described more than 60 years ago in several populations in Great Britain . Few studies of vole tuberculosis have been undertaken since then, and little is known about the relationship between M . microti isolates originating from different populations or at different times or of the prevalence of this infection in wild rodent populations, despite human cases of M . microti infections being increasingly reported . In this study, field voles (Microtus agrestis), bank voles (Clethrionomys glareolus), and wood mice (Apodemus sylvaticus) were found to be infected, with up to 8% having external tuberculous signs, in wild populations in Northumberland and Cheshire, England . Spoligotyping applied directly to the clinical material simultaneously detected and typed M . microti bacteria in skin lesions, lymph glands, and internal abcesses . IS6110 restriction fragment length polymorphism typing of cultured bacteria was used to compare these isolates with previously isolated strains from both animals and humans . This demonstrated that although the current rodent isolates were distinct from those isolated from voles in the 1930s in Great Britain, they had a high degree of similarity to these strains and were distinct from the M . microti isolates from humans, a pig, and a ferret from The Netherlands . Thus, M . microti infection seems to be widespread in wild rodent populations, but more studies are needed to understand how M . microti might be transmitted from animals to humans and to determine better the zoonotic risk posed.

Biophys J, 2002 Sep, 83(3), 1567 - 77
Structural change of site-directed mutants of PYP: new dynamics during pR state; Takeshita K et al.; The energetics, protein dynamics, and diffusion coefficients of three mutants of photoactive yellow protein, R52Q, P68A, and W119G, were studied by the transient grating and pulsed laser-induced photoacoustic method . We observed a new dynamics with a lifetime of approximately 1 micro s in the transient grating signal, which is silent by the light absorption technique . This fact indicates that, after the structure change around the chromophore is completed (pR(1)), the protein part located far from the chromophore is still moving to finally create another pR (pR(2)) species, which can transform to the next intermediate, pB . Although the kinetics of pR(2)-->pB-->pG are very different depending on the mutants, the enthalpies of the first long-lived (in micro seconds, 100-micro s range) intermediate species (pR(2)) are similar and very high for all mutants . The diffusion coefficients of the parent (pG) and pB species of the mutants are also similar to that of the wild-type photoactive yellow protein . From the temperature dependence of the volume change, the difference in the thermal expansion coefficients taken as indicator of the flexibility of the structure between pG and pR(2) is measured . They are also similar to that of the wild-type photoactive yellow protein . These results suggest that the protein structures of pR(2) and pB in these mutants are globally different from that of pG, and this structural change is not altered so much by the single amino acid residue mutation . This is consistent with the partially unfolded nature of these intermediate species . On the other hand, the volume changes during pR(1)-->pR(2) are sensitive to the mutations, which may suggest that the volume change reflects a rather local character of the structure, such as the chromophore-protein interaction.

Anal Biochem, 2002 Aug 15, 307(2), 191 - 201
Restriction landmark genomic scanning for DNA methylation in cancer: past, present, and future applications; Rush LJ et al.; The field of molecular biology was revolutionized by the advent of gel electrophoresis . Restriction landmark genomic scanning (RLGS) is a type of two-dimensional electrophoresis employed in the genome-wide assessment of genomic alterations . RLGS has been used to study genetic and epigenetic changes in normal tissues, primary tumors, cancer cell lines, and various organisms such as mice, rats, hamsters, bacteria, and plants . An RLGS profile displays over 2000 radiolabeled restriction landmark sites in a single assay . When conducted with methylation-sensitive restriction enzymes whose sites are preferentially located in CpG island regulatory regions, RLGS becomes a very versatile tool for the investigation of both normal and aberrant methylation patterns . Early studies performed on tumor DNA were mainly descriptive in nature, essentially a catalogue of loci that were changed to varying degrees in different tumor types . Over time, as investigators have become more proficient with RLGS and have undertaken high-throughput studies, the need for efficient cloning, imaging, and analysis systems has become paramount . Current studies focus on identifying specific genes and pathways involved in deregulated methylation in cancer . As such, RLGS analysis of tumor samples has made tremendous contributions to our understanding of the role of DNA methylation in cancer . Future directions will take advantage of the abundant genomic sequence data available to link all of the RLGS loci to genes and create biologically relevant methylation profiles of cancer . This review discusses practical considerations of using RLGS as a genome scanning tool and the past, present, and future applications in cancer biology.

Water Sci Technol, 2002, 45(12), 63 - 9
Waste management systems of dairy cattle farms in Japan; Shima E et al.; Recently, the size of livestock farms in Japan has been expanding and the pollution from farm wastes has become a serious problem in rural areas . Therefore it is necessary to design treatment strategies and improve the recycling of livestock manure for sustainability of agriculture in Japan . The dairy cattle waste management systems were studied at dairy farms in Aomori prefecture and in Hokkaido, Japan . The four farms, typical for the respective regions in Japan, were investigated on the basis of the land and livestock size, housing, overall farm and waste management, type of machinery and a farm labour force . A statistical comparison was made for housing, milking and waste handling systems of dairy farms . One of the waste handling strategies was aerobic slurry treatment and land irrigation of the treated liquid fraction . Such methods began to solve some of waste management problems created since 1967 in grassland farming areas of Hokkaido . The irrigation system supplies water fertiliser and organic material to land as well as shortening the spreading times . It recycles livestock resources, increases the soil fertility and rationalizes the farm management.

Water Sci Technol, 2002, 45(12), 271 - 8
Ultimate azo dye degradation in anaerobic/aerobic sequential processes; Sponza DT et al.; The treatability of Remazol Black-5 was studied in an anaerobic/aerobic sequential process . Laboratory scale UASB/CSTR reactors were used and operated at different organic loadings and HRTs to investigate the COD, color removal, and methane gas production efficiencies . The effect of both sludge age and HRT on the color and COD removal efficiencies were also investigated . The reactive dye used in this study contains the groups N=N, -SO3, S=O and is in use in some of the textile industries in Turkey . The studies were carried out in continuous mode and the effluent of the UASB reactor was used as feed in the CSTR reactor . COD removal efficiencies decreased from 56 to 27% with increases in COD loadings from 5 kg COD/m3.day and 25 kg COD/m3.day in the anaerobic UASB reactor . The color removals were 92 and 87%, respectively, for the aforementioned organic loadings . The methane percentages were found to be 50 and 76% at organic loading rates of 2.49 kg COD/m3.day and 14.8 kg COD/m3.day, respectively . 28, 42, and 90% COD removal efficiencies were obtained at sludge retention times of 1.7, 5.7 and 11 days in the aerobic CSTR reactor . Optimum sludge age was 11 days in aerobic reactor and 67 and 28% COD removal efficiencies were obtained at F/M ratios of 0.05-0.17 and 0.30-1.4 kg COD/kg MLSS.day . 90-95% color and 40-60% COD removal efficiencies were obtained depending on the applied organic loadings in the UASB reactor . The remaining COD was removed with a treatment efficiency of 85-90% in the aerobic CSTR reactor.

Water Sci Technol, 2002, 45(12), 113 - 8
Anaerobic digestion of organic waste in Japan: the first demonstration plant at Kyoto City; Komatsu T et al.; Recycling of Municipal Solid Waste is vigorously promoted in Japan and the necessity of energy recovery from organic waste is increasing . An anaerobic digestion demonstration plant for organic waste in Kyoto City, Japan has been operated for about two years . Three kinds of wastes (garbage and leftovers from hotels, yard waste and used paper) mixed at various ratios are used . The plant has maintained stable operations with each mixture, generating biogas by the decomposition of VS at the rate of about 820 m3N/ton-VS.

J Periodontal Res, 2002 Aug, 37(4), 268 - 72
Cytolethal distending toxin of Actinobacillus actinomycetemcomitans . Occurrence and association with periodontal disease; Tan KS et al.; The cytolethal distending toxin (Cdt) of Actinobacillus actinomycetemcomitans, a periodontal pathogen, is a newly described cytotoxin with immunosuppressive properties, capable of causing cell cycle arrest of lymphocytes . The objectives of this study were to investigate the occurrence of A . actinomycetemcomitans with the cdt genotype in the subgingival plaque of periodontitis patients and to determine the association of this bacterial genotype with periodontal disease . A total of 146 subgingival plaque samples from periodontitis patients were assayed by the PCR method using oligonucleotide primers targeting the cdt operon of A . actinomycetemcomitans . Primers targeting the leukotoxin gene A (ltxA) of A . actinomycetemcomitans was used to determine the occurrence of the bacteria in the plaque samples at baseline . At baseline, A . actinomycetemcomitans was detected in 106 out of 146 (73%) diseased sites studied . Among the 106 diseased sites found to harbor A . actinomycetemcomitans, 13 sites were positive for the bacteria with the cdt genotype (12%) . Out of the 13 positive sites, 10 sites were obtained from patients diagnosed with aggressive periodontitis (77%) . Thus, A . actinomycetemcomitans with the cdt genetic subtype has low occurrence in the subgingival plaque of periodontitis patients . However, a strong association was observed between the presence of the bacteria and aggressive forms of periodontitis . Thus, the cytotoxic and immunosuppressive properties of A . actinomycetemcomitans Cdt may function to cripple the host immunity and contribute to the pathogenesis of aggressive periodontitis.

J Exp Biol, 2002 Oct, 205(Pt 19), 3055 - 66
Effects of metabolite uptake on proton-equivalent elimination by two species of deep-sea vestimentiferan tubeworm, Riftia pachyptila and Lamellibrachia cf luymesi: proton elimination is a necessary adaptation to sulfide-oxidizing chemoautotrophic symbionts; Girguis PR et al.; Intracellular symbiosis requires that the host satisfy the symbiont's metabolic requirements, including the elimination of waste products . The hydrothermal vent tubeworm Riftia pachyptila and the hydrocarbon seep worm Lamellibrachia cf luymesi are symbiotic with chemolithoautotrophic bacteria that produce sulfate and protons as end-products . In this report, we examine the relationship between symbiont metabolism and host proton equivalent elimination in R . pachyptila and L . cf luymesi, and the effects of sulfide exposure on proton-equivalent elimination by Urechis caupo, an echiuran worm that lacks intracellular symbionts (for brevity, we will hereafter refer to proton-equivalent elimination as 'proton elimination') . Proton elimination by R . pachyptila and L . cf luymesi constitutes the worms' largest mass-specific metabolite flux, and R . pachyptila proton elimination is, to our knowledge, the most rapid reported for any metazoan . Proton elimination rates by R . pachyptila and L . cf luymesi correlated primarily with the rate of sulfide oxidation . Prolonged exposure to low environmental oxygen concentrations completely inhibited the majority of proton elimination by R . pachyptila, demonstrating that proton elimination does not result primarily from anaerobic metabolism . Large and rapid increases in environmental inorganic carbon concentrations led to short-lived proton elimination by R . pachyptila, as a result of the equilibration between internal and external inorganic carbon pools . U . caupo consistently exhibited proton elimination rates 5-20 times lower than those of L . cf luymesi and R . pachyptila upon exposure to sulfide . Treatment with specific ATPase inhibitors completely inhibited a fraction of proton elimination and sulfide and inorganic carbon uptake by R . pachyptila, suggesting that proton elimination occurs in large part via K(+)/H(+)-ATPases and Na(+)/H(+)-ATPases . In the light of these results, we suggest that protons are the primary waste product of the symbioses of R . pachyptila and L . cf luymesi, and that proton elimination is driven by symbiont metabolism, and may be the largest energetic cost incurred by the worms.

Appl Environ Microbiol, 2002 Sep, 68(9), 4684 - 8
Enhanced degradation of an endocrine-disrupting chemical, butyl benzyl phthalate, by Fusarium oxysporum f . sp . pisi cutinase; Kim YH et al.; Compared to yeast esterase, fungal cutinase degraded butyl benzyl phthalate (BBP) far more efficiently; i.e., almost 60% of the BBP disappeared within 7.5 h . Also, the final chemical composition significantly depended on the enzyme used . Toxicity monitoring using bioluminescent bacteria showed that butyl methyl phthalate, a major product of degradation by esterase, was an oxidative toxic hazard.

Appl Environ Microbiol, 2002 Sep, 68(9), 4642 - 5
Effect of Weissella confusa strain PL9001 on the adherence and growth of Helicobacter pylori; Nam H et al.; Viable and nonviable Weissella confusa strain PL9001 inhibited the binding of Helicobacter pylori to human gastric-cell line MKN-45 cells by more than 90% . Spent culture supernatant of PL9001 rapidly decreased the viability of H . pylori, rupturing cell walls . The results suggest that PL9001 is a probiotic that can reduce the infectivity and persistence of H . pylori.

Appl Environ Microbiol, 2002 Sep, 68(9), 4441 - 7
Effect of modified atmosphere composition on the metabolism of glucose by Brochothrix thermosphacta; Pin C et al.; The influence of atmosphere composition on the metabolism of Brochothrix thermosphacta was studied by analyzing the consumption of glucose and the production of ethanol, acetic and lactic acids, acetaldehyde, and diacetyl-acetoin under atmospheres containing different combinations of carbon dioxide and oxygen . When glucose was metabolized under oxygen-free atmospheres, lactic acid was one of the main end products, while under atmospheres rich in oxygen mainly acetoin-diacetyl was produced . The proportions of the total consumed glucose used for the production of acetoin (aerobic metabolism) and lactic acid (anaerobic metabolism) were used to decide whether aerobic or anaerobic metabolism predominated at a given atmosphere composition . The boundary conditions between dominantly anaerobic and aerobic metabolisms were determined by logistic regression . The metabolism of glucose by B . thermosphacta was influenced not only by the oxygen content of the atmosphere but also by the carbon dioxide content . At high CO(2) percentages, glucose metabolism remained anaerobic under greater oxygen contents.

Nature, 2002 Aug 29, 418(6901), 967 - 70 Epub 2002 Aug 05.
Pfiesteria shumwayae kills fish by micropredation not exotoxin secretion; Vogelbein WK et al.; Pfiesteria piscicida and P . shumwayae reportedly secrete potent exotoxins thought to cause fish lesion events, acute fish kills and human disease in mid-Atlantic USA estuaries . However, Pfiesteria toxins have never been isolated or characterized . We investigated mechanisms by which P . shumwayae kills fish using three different approaches . Here we show that larval fish bioassays conducted in tissue culture plates fitted with polycarbonate membrane inserts exhibited mortality (100%) only in treatments where fish and dinospores were in physical contact . No mortalities occurred in treatments where the membrane prevented contact between dinospores and fish . Using differential centrifugation and filtration of water from a fish-killing culture, we produced 'dinoflagellate', 'bacteria' and 'cell-free' fractions . Larval fish bioassays of these fractions resulted in mortalities (60-100% in less than 24 h) only in fractions containing live dinospores ('whole water', 'dinoflagellate'), with no mortalities in 'cell-free' or 'bacteria'-enriched fractions . Videomicrography and electron microscopy show dinospores swarming toward and attaching to skin, actively feeding, and rapidly denuding fish of epidermis . We show here that our cultures of actively fish-killing P . shumwayae do not secrete potent exotoxins; rather, fish mortality results from micropredatory feeding.

Alcohol Clin Exp Res, 2002 Aug, 26(8 Suppl), 66S - 69S
Estriol enhances lipopolysaccharide-induced increases in nitric oxide production by Kupffer cells via mechanisms dependent on endotoxin; Enomoto N et al.; BACKGROUND: Estriol causes sensitization of Kupffer cells to lipopolysaccharide (LPS) via mechanisms dependent on gut-derived LPS . Accordingly, this study examines the effect of estriol treatment on nitric oxide (NO) production from Kupffer cells . METHODS: Rats were given estriol (20 mg/kg body weight) intraperitoneally, and Kupffer cells were isolated 24 hr later . Some rats were treated for 4 days with 150 mg/kg/day of polymyxin B and 450 mg/kg/day of neomycin to prevent growth of intestinal bacteria, the primary source of endotoxin in the gastrointestinal tract . After addition of LPS, NO production by Kupffer cell was detected using a fluorescence indicator, DAF-2 . RESULTS: Twenty-four hours after estriol administration, LPS-induced NO production by Kupffer cells was enhanced as compared with control Kupffer cells . Sterilization of the gut with antibiotics blocked this enhancement . CONCLUSIONS: Estriol treatment in vivo enhances LPS-induced NO production in Kupffer cells.

EMBO J, 2002 Sep 2, 21(17), 4420 - 8
A dynamically localized histidine kinase controls the asymmetric distribution of polar pili proteins; Viollier PH et al.; Each cell division in Caulobacter crescentus is asymmetric, yielding a swarmer cell with several polar pili and a non-piliated stalked cell . To identify factors contributing to the asymmetric biogenesis of polar pili, cytological studies of pilus assembly components were performed . We show here that the CpaC protein, which is thought to form the outer membrane pilus secretion channel, and its assembly factor, CpaE, are localized to the cell pole prior to the polymerization of the pilus filament . We demonstrate that the PleC histidine kinase, a two-component signal transduction protein shown previously to localize to the piliated cell pole before and during pilus assembly, controls the accumulation of the pilin subunit, PilA . Using an inactive form of PleC (PleCH610A) that lacks the catalytic histidine residue, we provide evidence that PleC activity is responsible for the asymmetric distribution of CpaE and itself to only one of the two cell poles . Thus, a polar signal transduction protein controls its own asymmetric location as well as that of a factor assembling a polar organelle.

Aliment Pharmacol Ther, 2002 Sep, 16(9), 1591 - 602
Review article: lactose--a potential prebiotic; Szilagyi A; Lactose maldigestion, which affects a large majority of the world's population, has been mostly linked with uncomfortable symptoms . In addition, dairy consumption is variably blamed or recommended for a number of ill effects . There is, however, emerging evidence that certain lactic acid-producing bacteria, which selectively consume prebiotics, may be beneficial against some lower intestinal diseases . Lactose maldigestion and lactose should perhaps be re-evaluated as a potential provider of such a prebiotic . This historical and observational review discusses lactose and argues the opinion that it has prebiotic potential . Moreover, in maldigesters, natural ingestion or lack thereof may be relevant in the pathogenesis of diseases such as colorectal cancer and inflammatory bowel diseases.

Biochem Soc Trans, 2002 Aug, 30(4), 715 - 8
Mercury transport and resistance; Brown NL et al.; Resistance to mercuric ions in bacteria is conferred by mercuric reductase, which reduces Hg(II) to Hg(0) in the cytoplasmic compartment . Specific mercuric ion transport systems exist to take up Hg(II) salts and deliver them to the active site of the reductase . This short review discusses the role of transport proteins in resistance and the mechanism of transfer of Hg(II) between the mercury-resistance proteins.

Biochem Soc Trans, 2002 Aug, 30(4), 621 - 4
Controlling the reactivity of radical intermediates by coenzyme B(12)-dependent methylmalonyl-CoA mutase; Banerjee R et al.; Adenosylcobalamin or coenzyme B(12)-dependent enzymes are members of the still relatively small group of radical enzymes and catalyse 1,2-rearrangement reactions . A member of this family is methylmalonyl-CoA mutase, which catalyses the isomerization of methylmalonyl-CoA to succinyl-CoA and, unlike the others, is present in both bacteria and animals . Enzymes that catalyse some of the most chemically challenging reactions are the ones that tend to deploy radical chemistry . The use of radical intermediates in an active site lined with amino acid side chains that threaten to extinguish the reaction by presenting alternative groups for abstraction poses the conundrum of how the enzymes control their reactivity . In this review, insights into this issue that have emerged from kinetic, mutagenesis and structural studies are described for methylmalonyl-CoA mutase.

Biochem Soc Trans, 2002 Aug, 30(4), 613 - 20
Biosynthesis of cobalamin (vitamin B(12)); Scott AI et al.; The biosynthesis of vitamin B(12) is summarized, emphasizing the differences observed between the aerobic and anaerobic pathways . The biosynthetic route to adenosylcobalamin from its five-carbon precursor, 5-aminolaevulinic acid, can be divided into three sections: (1) the biosynthesis of uroporphyrinogen III from 5-aminolaevulinic acid, which is common to both pathways; (2) the conversion of uroporphyrinogen III into the ring-contracted, deacylated intermediate precorrin 6 or cobalt-precorrin 6, which includes the primary differences between the two pathways; and (3) the transformation of this intermediate to form adenosylcobalamin.

Biochem Soc Trans, 2002 Aug, 30(4), 579 - 84
Structure and function of glutamyl-tRNA reductase involved in 5-aminolaevulinic acid formation; Moser J et al.; In most bacteria, in archaea and in plants, the general precursor of all tetrapyrroles, 5-aminolaevulinic acid, is formed by two enzymes . The initial substrate, glutamyl-tRNA, is reduced by NADPH-dependent glutamyl-tRNA reductase to form glutamate 1-semialdehyde . The aldehyde is subsequently transaminated by glutamate-1-semialdehyde 2,1-aminomutase to yield 5-aminolaevulinic acid . The enzymic mechanism and the solved crystal structure of Methanopyrrus kandleri glutamyl-tRNA reductase are described . A pathway for metabolic channelling of the reactive aldehyde between glutamyl-tRNA reductase and the aminomutase is proposed.

BioDrugs, 2002, 16(4), 241 - 59
Biological imaging for the diagnosis of inflammatory conditions; Signore A et al.; Radiopharmaceuticals used for in vivo imaging of inflammatory conditions can be conveniently classified into six categories according to the different phases in which the inflammatory process develops . The trigger of an inflammatory process is a pathogenic insult (phase I) that causes activation of endothelial cells (phase II); there is then an increase of vascular permeability followed by tissue oedema (phase III) . Phase IV is characterised by infiltration of polymorphonuclear cells, and a self-limiting regulatory process called apoptosis is observed (phase V) . If the inflammatory process persists, late chronic inflammation takes place (phase VI) . In some pathological conditions, such as organ-specific autoimmune diseases, chronic inflammation is present early in the disease . The aim of nuclear medicine in the field of inflammation/infection is to develop noninvasive tools for the in vivo detection of specific cells and tissues . This would allow early diagnosis of initial pathophysiological changes that are undetectable by clinical examination or by other diagnostic tools, and could also be used to evaluate the state of activity of the disease during therapy . These potential applications are of great interest in clinical practice . In this review, we describe the various approaches that have been developed in the last 25 years of experience . Recent advances in the diagnosis of inflammatory processes have led to the development of specific radiopharmaceuticals that are intended to allow specific stage-related diagnosis.

J Environ Monit, 2002 Aug, 4(4), 553 - 7
The potential for anaerobic mineralisation of hydrocarbon constituents of oily drill cuttings from the North Sea seabed; Artz RR et al.; The potential for natural attenuation of hydrocarbons in oily drill cuttings from the seabed beneath a North Sea oil platform was investigated . The study focused on the anaerobic degradation of n-hexadecane, n-octacosane and naphthalene using additions of 14C-labelled analogues to drill cuttings samples and was conducted under realistic seabed conditions (except pressure) over an 11-month period . No mineralisation of naphthalene was detected over this time period and mineralisation of octacosane represented only 0.5-1.5% of the added label . In contrast, mineralisation of hexadecane was 10-49% after 11 months of incubation . Selective inhibition of key functional bacterial groups revealed the key role of both sulfate reduction and methanogenesis in the degradation process . This study demonstrates the potential for natural attenuation of at least some hydrocarbon constituents of oily drill cuttings under realistic environmental conditions and highlights the involvement of a wide functional consortium in the natural attenuation process.

Nat Prod Rep, 2002 Aug, 19(4), 494 - 513
Triterpenoids; Connolly JD et al.; This review covers the isolation and structure determination of triterpenoids including squalene derivatives, lanostanes, cycloartanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, isomalabicanes and saponins . The literature from January to December 2000 is reviewed and 277 references are cited.

Nat Prod Rep, 2002 Aug, 19(4), 390 - 412
The biosynthesis of adenosylcobalamin (vitamin B12); Warren MJ et al.; Vitamin B12, or cobalamin, is one of the most structurally complex small molecules made in Nature . Major progress has been made over the past decade in understanding how this synthesis is accomplished . This review covers some of the most important findings that have been made and provides the reader with a complete description of the transformation of uroporphyrinogen III into adenosylcobalamin (AdoCbl) . 183 references are cited.

Dev Cell, 2002 Aug, 3(2), 245 - 57
Lateral propagation of EGF signaling after local stimulation is dependent on receptor density; Sawano A et al.; We analyzed lateral propagation of epidermal growth factor (EGF) signaling in single live COS cells following local stimulation, achieved by the use of laminar flows containing rhodamine-labeled EGF . The spatiotemporal pattern of EGF signaling was visualized by fluorescent indicators for Ras activation and tyrosine phosphorylation . Contrary to the findings in previous reports, both signals were localized to the stimulated regions in control COS cells expressing EGF receptor at the basal level . However, the signals spread over the entire cell when EGF receptors were overexpressed or when receptor/ligand endocytosis was blocked . We thus present evidence that ligand-independent propagation of EGF signaling occurs only when the receptor density on the plasma membrane is high, such as in carcinoma cells.

Emerg Infect Dis, 2002 Sep, 8(9), 983 - 6
First detection of spotted fever group rickettsiae in Ixodes ricinus from Italy; Beninati T et al.; Ixodes ricinus from Italy were examined for the first time to detect whether rickettsiae were present . Using molecular methods, we detected three different spotted fever group rickettsiae, including Rickettsia helvetica . Our results raise the possibility that bacteria other than R . conorii are involved in rickettsial diseases in Italy.

Postepy Hig Med Dosw, 2002, 56(3), 307 - 13
{Role and function of voltage-gated chloride channels of the CIC family and their defects leading to genetic diseases}; Dolowy K et al.; There are 9 channels of the ClC family in mammals and few others in fishes, plants, yeast and bacteria . The ClC channels are present in different tissues and play a role in transmembrane potential stabilization, transepithelial transport, cell volume regulation, acidification of intracellular organelles . The genetic defects of ClC-1 chloride channel lead to myotonias, the defect in ClC-5 channel to the formation of stones in kidney, while the defect in ClC-Kb channel leads to the Bartter's syndrome.

Bioessays, 1999 Jan, 21(1), 1 - 4
The Tom channel in the mitochondrial outer membrane: alive and kicking; Bains G et al.; The targeting of newly-made polypeptides to specific membranes, and the subsequent ability of a membrane to allow only certain polypeptides into its compartment, are essential to maintain the ultrastructure of Eukaryotic cells . Distinct oligomeric protein complexes in each cellular membrane catalyse these translocation processes . A recent report {Hill K et al . Nature 1998;395:516-521 (Ref . 1)} of the reconstitution of the translocation channel from the mitochondrial outer membrane, after producing the major structural component of the channel by recombinant means, promises a system to dissect in molecular detail the exact working of one of these protein translocation machines.

Gynecol Endocrinol, 2002 Jun, 16(3), 225 - 33
Gender differences in contractile and relaxing responses of aortic rings from lipopolysaccharide-treated rats; Okawa T et al.; Aortic rings from male and female Sprague-Dawley rats were placed in organ chambers filled with Krebs solution, and the isometric tension was recorded . There were no gender differences in responses to potassium chloride or phenylephrine in either intact or endothelium-denuded rings from control animals . Treatment with 10 mg/kg of lipopolysaccharide (LPS) attenuated the contractile response to potassium chloride in intact, but not in endothelium-denuded rings, and suppressed the phenylephrine contractions in rings both with and without endothelium from male and female rats . Endothelium-dependent and--independent relaxation by acetylcholine and the nitric oxide donor diethylamine/NO, respectively, did not depend on gender and were equally suppressed by LPS treatment . Treatment with LPS accentuated the effects of oxyhemoglobin in rings with and without endothelium and this was significantly larger in rings from females compared to males . Thus, gender differences were present in the effect of LPS on vascular responses . LPS induced a greater inhibition of depolarization by potassium chloride, but not receptor-activated contractions, in aortic rings from female verus male rats.

Curr Microbiol, 2002 Oct, 45(4), 255 - 60
Wolbachia infections of tephritid fruit flies: molecular evidence for five distinct strains in a single host species; Jamnongluk W et al.; Endosymbiotic bacteria of the genus Wolbachia are widespread among arthropods and can induce cytoplasmic incompatibility, thelytokous parthenogenesis, male-killing or feminization in their hosts . Here, we report phylogenetic relationships of Wolbachia in tephritid fruit flies based on wsp gene sequences . We also report, for the first time, five distinct strains of Wolbachia in Bactrocera ascita sp . B . Four of the five Wolbachia strains found in this species were in the same groups as those found in other tephritid fruit flies, suggesting possible horizontal transmission of Wolbachia from other fruit flies into B . ascita sp . B . The unreliability of wsp-specific group primers demonstrated in this study suggests that these primers might be useful only for preliminary identification of Wolbachia . Final determination of group affiliation needs to be verified with wsp sequence data.

J Biol Chem, 2002 Nov 22, 277(47), 44660 - 9 Epub 2002 Aug 20.
Transient state kinetic investigation of 5-aminolevulinate synthase reaction mechanism; Zhang J et al.; 5-Aminolevulinate synthase (ALAS), a pyridoxal 5'-phosphate-dependent enzyme, catalyzes the first, and regulatory, step of the heme biosynthetic pathway in nonplant eukaryotes and some bacteria . 5-Aminolevulinate synthase is a dimeric protein having an ordered kinetic mechanism with glycine binding before succinyl-CoA and with aminolevulinate release after CoA and carbon dioxide . Rapid scanning stopped-flow absorption spectrophotometry in conjunction with multiple turnover chemical quenched-flow kinetic analyses and a newly developed CoA detection method were used to examine the ALAS catalytic reaction and identify the rate-determining step . The reaction of glycine with ALAS follows a three-step kinetic process, ascribed to the formation of the Michaelis complex and the pyridoxal 5'-phosphate-glycine aldimine, followed by the abstraction of the glycine pro-R proton from the external aldimine . Significantly, the rate associated with this third step (k(3) = 0.002 s(-1)) is consistent with the rate determined for the ALAS-catalyzed removal of tritium from {2-(3)H(2)}glycine . Succinyl-CoA and acetoacetyl-CoA increased the rate of glycine proton removal approximately 250,000- and 10-fold, respectively, supporting our previous proposal that the physiological substrate, succinyl-CoA, promotes a protein conformational change, which accelerates the conversion of the external aldimine into the initial quinonoid intermediate (Hunter, G . A., and Ferreira, G . C . (1999) J . Biol . Chem . 274, 12222-12228) . Rapid scanning stopped-flow and quenched-flow kinetic analyses of the ALAS reaction under single turnover conditions lend evidence for two quinonoid reaction intermediates and a model of the ALAS kinetic mechanism in which product release is at least the partially rate-limiting step . Finally, the carbonyl and carboxylate groups of 5-aminolevulinate play a major protein-interacting role by inducing a conformational change in ALAS and, thus, possibly modulating product release.

Dent Mater, 2002 Nov, 18(7), 543 - 51
Response of human pulps following acid conditioning and application of a bonding agent in deep cavities; de Souza Costa CA et al.; OBJECTIVES: The aim of this in vivo study was to evaluate the human dental pulp response when a one-bottle adhesive system was applied on etched or unetched deep dentine . METHODS: Eighteen class V deep cavity preparations were divided in three groups: group 1-total etching + two coats of single bond (SB) + composite resin (Z-100); group 2-enamel etching + two coats of SB + Z-100; group 3-cavity floor lined with a calcium hydroxide liner (Dycal) + acid-etching of enamel and lateral walls + two coats of SB + Z-100 . Two teeth were used as intact control group . After 30 days the teeth were extracted and processed through H and E, Masson's trichrome and Brown and Brenn staining techniques . RESULTS: Moderate inflammatory response, disorganization of pulp tissue, as well as, deposition of thin layer of reactionary dentin were observed in group 1 teeth in which the remaining dentin thickness (RDT) was less than 300 microm . These histological findings appear to be related to long resin tags formation and bonding agent diffusion through dentinal tubules . In group 2, slight inflammatory response was observed only in one tooth in which the RDT was 162 microm . In group 3, all the teeth showed normal histological characteristics which were similar to the intact control group . Presence of bacteria was not correlated with the intensity of pulpal response . The patients reported no symptoms during the experiment . Radiographic evaluation showed no periapical pathology for any of the teeth . SIGNIFICANCE AND CONCLUSIONS: Acid-etched deep dentin (RDT less than 300 microm) lined with SB causes more intense pulpal response than unetched deep dentin . Based on the results observed in the present study and the conditions in which it was carried out, we recommend the application of a biocompatible liner before etching deep dentin and applying SB .

Pathologe, 2002 Jul, 23(4), 241 - 51
{Human prion diseases}; Kretzschmar HA et al.; Prion diseases are rare neurodegenerative transmissible fatal diseases affecting humans and mammals . The causative agent is a novel pathogen termed the prion . Unlike classical infectious agents such as bacteria or viruses, prions lack an independent genome and consist largely of an abnormal form of the host-encoded prion protein . Creutzfeldt-Jakob disease (CJD) is the main representative of human prion diseases that may be sporadic in most cases, hereditary, or acquired . Clinical examination yields only a suspected diagnosis with formal criteria for probable or possible . Definite diagnosis relies on autopsy and neuropathology findings . This is also true for the new variant CJD (vCJD), a previously unknown prion disease of humans that is connected with the same strain of prions as found in bovine spongiform encephalopathy (BSE) . The autopsy and handling of laboratory material for histopathological examination requires specific precautionary measures and decontamination . For definite histopathological diagnosis of a human prion disease, immunohistochemical detection of the prion protein deposits is the gold standard . Furthermore, molecular and genetic investigations are necessary for classification because a close correlation could be established between distinct CJD phenotypes, codon 129 genotypes of the prion protein gene, and the prion protein type.

Platelets, 2002 Jun, 13(4), 219 - 22
The virucidal effect of platelet concentrates: preliminary study and first conclusions; Maurice A et al.; Despite the increased safety of blood components, achieved through improved donor selection and testing, transfusion recipients remain at risk of transfusion-associated diseases . Transfusion of cellular blood components has been implicated in transmission of viral, bacterial and protozoan diseases . Investigators have studied a myriad of processes for pathogen depletion and/or inactivation . No successful treatments, apart the leukodepletion, have already been identified for red cells and platelets . And more, several evidences indicate that platelets play a key role in host defence against infection . High levels of pathogens were added to single-donor platelet concentrates (PC) containing 3 to 5 10(11) platelets in 300 ml . The infectivity of each pathogen was measured with established biologic assays . The following levels of pathogen inactivation were achieved : >10(2.63) plaque-forming units (PFU) per ml of adenovirus 5 (ADV5), >10(5.6) PFU per ml of Poliovirus 1 (P1) and >10(4.1) PFU per ml of vaccinia virus (VaV) . In conclusion, the PC show a potential virucidal effect . This inactivation process has been found with bacteria and still remains unknown for viruses.

Phys Rev E Stat Nonlin Soft Matter Phys . 2002 Jun;65(6 Pt 1):061909 . Epub 2002 Jun 21.
Class of self-limiting growth models in the presence of nonlinear diffusion; Kar S et al.; The source term in a reaction-diffusion system, in general, does not involve explicit time dependence . A class of self-limiting growth models dealing with animal and tumor growth and bacterial population in a culture, on the other hand, are described by kinetics with explicit functions of time . We analyze a reaction-diffusion system to study the propagation of spatial front for these models.

Water Sci Technol, 2002, 45(10), 99 - 104
Hydrolysis kinetics of dissolved polymer substrates; Sanders WT et al.; In this paper, the relation between the hydrolysis rate of dissolved polymer substrates and sludge concentration was investigated in two ways, viz . by laboratory experiments and by computer simulations . In the simulations, the hydrolysis of dissolved polymer components was regarded as a general depolymerisation process in which the bonds of the parent molecule break randomly until only monomer and dimer components remain . The results illustrate that for the hydrolysis of dissolved polymer substrates the enzyme activity is the rate-limiting factor . Moreover, a general depolymerisation process can describe the enzymatic hydrolysis of these components.

Water Sci Technol, 2002, 45(10), 75 - 80
Competition for H2 between sulfate reducers, methanogens and homoacetogens in a gas-lift reactor; Weijma J et al.; Reported values for growth kinetic parameters show an order in competitivity of heterotrophic sulfate reducing bacteria>methanogens>homoacetogens for the substrate hydrogen . This order suggests that methanogens can succesfully compete with consortia of heterotrophic SRB and homoacetogens when H2/CO2 is present as sole substrate . However, we found in experiments using gas-lift reactors inoculated with anaerobic sludge and fed with H2/CO2 and sulfate, that heterotrophic sulfate reduction rapidly and completely outcompeted methanogenesis, whereas a low amount of acetate was formed . Thus, in disagreement with the above competitivity order, hydrogen is more readily consumed by homoacetogenesis than by methanogenesis, indicating that the competition is not kinetically determined . The superior settling velocity of sulfidogenic-acetogenic sludge compared to that of methanogenic sludge suggests that the former sludge is better retained, which can explain the predominance of sulfate reduction/homoacetogenesis over methanogenesis.

Water Sci Technol, 2002, 45(10), 305 - 12
Measuring metal and phosphorus speciation in P-rich anaerobic digesters; Carliell-Marquet CM et al.; High concentrations of soluble orthophosphate, magnesium and potassium are released during anaerobic digestion of biological phosphorus removal (BPR) sludge . This research was undertaken to investigate the effects of phosphorus enrichment on digester performance, metal and phosphorus speciation . High concentrations of soluble PO4-P (> 250 mg/l) were found to have a retarding effect on anaerobic digestion, reducing the rate of volatile solids digestion and methane production in comparison to control digesters . This was found to be reversible after a period of time, which was related to the amount of PO4-P added to the digesters, higher concentrations of PO4-P requiring more time for digester recovery . Addition of magnesium and potassium to the digesters, together with PO4-P, reduced the inhibitory effect of phosphorus enrichment but these digesters still showed lower rates of volatile solids digestion and methane production in comparison to the control digesters . Phosphorus enrichment resulted in extensive precipitation of calcium, magnesium and manganese, markedly reducing the soluble and easily available fractions of these metals . Other trace metals such as copper, zinc, chromium, nickel and cobalt actually showed increased levels of solubility as a result of phosphorus enrichment . This was thought to be caused by high levels of soluble organic carbon in the phosphorus-rich anaerobic digesters, which acted as organic ligands for metal complexation.

Water Sci Technol, 2002, 45(10), 287 - 92
Sulfate disinfection, stabilisation and heavy metal removal from sewage sludge--process description and preliminary results; Lowrie D et al.; A new, closed loop process for the disinfection, stabilisation and removal of heavy metal from sewage sludge (consisting of a sludge/sulfuric acid reactor, hybrid H2S generator and H2S bioscrubber) is described . Preliminary results for total solids (TS), volatile suspended solids (VSS), chemical oxygen demand (COD), acetate and propionate destruction in the hybrid H2S generator have shown that digestion efficiency is not compromised in a hybrid reactor generating H2S compared to a methanogenic reactor . 70% of the electron flow in the hybrid H2S generator was diverted to methane at a COD:SO4 ratio of 5.45:1 . Enough H2SO4 could be generated from the H2S emitted at this ratio to effect sufficient metal solubilisation and pathogen removal from primary sludge.

Water Sci Technol, 2002, 45(10), 275 - 80
Co-digestion of energy crops and industrial confectionery by-products with cow manure: batch-scale and farm-scale evaluation; Kaparaju P et al.; The possible co-digestion of energy crops and industrial confectionery by-products with cow manure was evaluated firstly, through long-term batch experiments and secondly, in a farm-scale digester . In batch assays, digestion with mesophilically digested cow manure as inoculum resulted in specific methane yields (m3 kg(-1) VS added waste) of 0.35 for grass hay (particle size <1.0 cm); 0.26 for oats (0.5 cm) and 0.21 for clover (2.0 cm) harvested at vegetative stage and 0.14 (2.0 cm) for clover harvested at flowering stage . Specific methane yields (m3 kg(-1) VS added waste) for confectionery by-products were 0.37 for chocolate, 0.39 for black candy and 0.32 for confectionery raw material . Out the three particle sizes (2.0, 1.0 and 0.5 cm) tested, particle size of 1.0 cm was found ideal for digestion of grass hay and clover while, particle size reduction did not influence methane production from oats . Stage of the crop influenced the methane yields, with clover harvested at vegetative stage yielding 33% higher methane than when harvested at flowering stage . An approximate 60% enhancement in methane yield was noticed with the co-digestion of industrial confectionery wastes with cow manure in a full-scale farm digester.

Water Sci Technol, 2002, 45(10), 261 - 8
A novel in-situ sampling and VFA sensor technique for anaerobic systems; Pind PF et al.; A key information for understanding and controlling the anaerobic biogas process is the concentration of Volatile Fatty Acids (VFA) . However, access to this information has so far been limited to off-line measurements by manual time and labour consuming methods . We have developed a new technique that has made it possible to monitor VFA on-line in one of the most difficult media: animal slurry or manure . A novel in-situ filtration technique has made it possible to perform microfiltration inside the reactor system . This filter enables sampling from closed reactor systems without large scale pumping and filtering . Using this filtration technique together with commercially available membrane filters we have constructed a VFA sensor system that can perform automatic analysis on animal slurry at a frequency as high as every 15 minutes . The VFA sensor has been tested for a period of more than 60 days with more than 1000 samples on both a full-scale biogas plant and lab-scale reactors . The measuring range covers specific measurements of acetate, propionate, iso-/n-butyrate and iso-/n-valerate from 0.1 to 50 mM (6-3,000 mg).

Water Sci Technol, 2002, 45(10), 249 - 54
A comparative analysis of a balance between the rates of polymer hydrolysis and acetoclastic methanogenesis during anaerobic digestion of solid waste; Vavilin VA et al.; A distributed model of anaerobic digestion of solid waste was developed . Waste, volatile fatty acids (VFA), methanogenic biomass and methane concentrations were the model variables . A system of parabolic partial differential equations in the one space variable and time with slab, cylindrical or spherical symmetry of the problem was solved numerically . Diffusion of VFA inhibiting both polymer hydrolysis and acetoclastic methanogenesis was taken into account . The model showed that concentration waves of methanogenic biomass and VFA propagated over reaction space . Diffusion-based "acceleration" of methane production in the reactor was possible when intensity of VFA utilisation in the methanogenic area was sufficient for complete digestion of incoming VFA . Otherwise, methanogenic area propagation would be suppressed . Optimum conditions for the solid waste digestion can be reached at low mass transfer at the beginning and at high mass transfer when methanogenic population increases . If the initial methanogenic biomass was localised at the centre of the reactor, the total reaction time was shorter as compared to the case when the initial biomass was uniformly distributed over the reactor volume . In the last case, there was no concentration wave propagation.

Water Sci Technol, 2002, 45(10), 213 - 8
Anaerobic digestion of olive oil mill effluents together with swine manure in UASB reactors; Aangelidaki I et al.; Combined anaerobic digestion of olive oil mill effluent (OME) with swine manure, was investigated . In batch experiments was shown that for anaerobic degradation of OME alone nitrogen addition was needed . A COD:N ratio in the range of 65:1 to 126:1 was necessary for the optimal degradation process . Furthermore, it was found that methane productions rates during digestion of either swine manure alone or OME alone were much lower than the rates achieved when OME and manure were digested together . Admixing OME with manure at a concentration of 5 to 10% OME resulted in the highest methane production rates . Using upflow anaerobic sludge blanket (UASB) reactors, it was shown that codigestion of OME with swine manure (up to 50% OME) was successful with a COD reduction up to 75% . The process was adapted for degradation of OME with stepwise increase of the OME load to the UASB reactor . The results showed that the high content of ammonia in swine manure, together with content of other nutrients, make it possible to degrade OME without addition of external alkalinity and without addition of external nitrogen source . Anaerobic treatment of OME in UASB reactors resulted in reduction of simple phenolic compounds such as mequinol, phenyl ethyl alcohol and ethyl methyl phenol . After anaerobic treatment the concentration of these compounds was reduced between 75 and 100% . However, the concentration of some degradation products such as methyl phenol and ethyl phenol were detected in significantly higher concentrations after treatment, indicating that the process has to be further optimised to achieve satisfactory removal of all xenobiotic compounds.

Water Sci Technol, 2002, 45(10), 151 - 6
Removal of 3-chlorobenzoate using an upflow anaerobic sludge blanket reactor under light conditions; Sawayama S et al.; The possibility of 3-chlorobenzoate removal from water using an upflow anaerobic sludge blanket (UASB) reactor without the addition of any extra dechlorinating culture under light conditions has been studied on a laboratory scale . Benzoate removal was observed in the first three months of operation under light conditions, but the 3-chlorobenzoate removal was not observed . After three months of operation under light conditions, the 3-chlorobenzoate concentration in the UASB reactor effluent gradually decreased to less than 1 mg x h(-1) . The 3-chlorobenzoate concentration in the effluent did not increase under dark conditions . The DOC concentration in the effluent decreased according to the removal of the 3-chlorobenzoate by the UASB granules . These results indicated that granules in the UASB reactor provided the 3-chlorobenzoate removability after 80-100 d of adaptation to the 3-chlorobenzoate, and that the UASB reactor is useful for 3-chlorobenzoate removal.

Water Sci Technol, 2002, 45(10), 139 - 44
Anaerobic degradation of oleic acid by suspended and granular sludge: identification of palmitic acid as a key intermediate; Pereira MA et al.; The aim of the present work was to study the maximum potential methane production in batch assays of sludge samples taken along the operation of two EGSB reactors (RI inoculated with granular sludge and RII inoculated with suspended sludge) fed with increasing oleic acid concentrations between 2 and 8 gCOD/l (HRT = 1 day) . After removing the residual substrate, the sludge was incubated in batch vials without any added carbon source . A maximum methane production rate of 152+/-21 mlCH4(STP)/gVS.day was obtained for the suspended sludge taken on day 70, when oleate at a concentration of 2 g COD/l was fed with a co-substrate (50% COD) . The maximum plateau achieved in the methane production curve was 1145+/-307 mlCH4(STP)/gVS, obtained for the suspended sludge taken on day 162, when oleate was fed as the sole carbon source at 6 g COD/I . The methanization rate of the adsorbed substrate was enhanced under stirring conditions and was inhibited by adding oleic acid . Extraction and GC analysis confirmed that the main adsorbed substrate was palmitate, and not oleate . Accumulated palmitate adsorbed onto the sludge and further beta-oxidation was inhibited when in the presence of oleic acid . If oleic acid was removed from the medium beta-oxidation proceeded with methane production . Suspended sludge was more efficient than granular sludge.

Biotechniques, 2002 Aug, 33(2), 338 - 44, 346
A decade of differential display; Liang P; It has been 10 years since the invention of differential display (DD), a conceptually simple methodology that allows the detection and identification of differentially expressed genes . In the past decade, the number of publications describing successful applications of DD has outnumbered those using any other competing methodologies, including subtractive hybridization, representational difference analysis, serial analysis of gene expression, and DNA microarrays . This review will provide a glimpse of the current progress made in DD technological development, refinement, and automation . Excellent examples of DD applications in studying a variety of biological problems, in such diverse biological systems as bacteria, yeast, flies, plants, and higher mammals, are presented to provide a roadmap for those who would like to pursue a fruitful gene "fishing" expedition . Some of the fundamental differences between DD and DNA microarrays are also discussed.

Water Res, 2002 Jul, 36(13), 3253 - 60
Toxicity of linear alkylbenzene sulfonate in anaerobic digestion: influence of exposure time; Mosche M et al.; The inhibition of anaerobic digestion by the anionic surfactant linear alkylbenzene sulfonate was studied . The development of bacterial activity during several weeks was monitored by performing batch degradation tests with acetate and propionate . In the first phase the decay of activity without surfactant addition was studied . After the addition of the surfactant an immediate inhibition was detected . Subsequently, the degradation activity continued to decrease with increasing exposure time . Both, the immediate inhibition and the rate of the subsequent decrease of activity were dependent on the surfactant concentration . A kinetic model is presented that describes this behavior . A surfactant concentration of 14 mg L(-1) causes a 50% immediate inhibition of acetate degradation (27 mg L(-1) in the case of propionate degradation) . Additionally, each 12 mg L(-1) of surfactant increases the decay rate of acetate degradation activity by a factor 10 (23 mg L(-1) for propionate degradation) . A deviation from this model occurs at low surfactant concentrations (<3 mg L(-1)), where a slight stimulation of bacterial activity was observed . The above-mentioned concentrations refer to measured surfactant concentrations . These were substantially lower than the nominal concentrations (added surfactant per volume) . This discrepancy is explained by adsorption of the surfactant to the biomass . Finally, the importance of the presented kinetic model and the significance of surfactant toxicity for anaerobic digestion are discussed.

Water Res, 2002 Jul, 36(13), 3175 - 82
Semi-continuous anaerobic digestion of solid poultry slaughterhouse waste: effect of hydraulic retention time and loading; Salminen EA et al.; We studied the effect of hydraulic retention time (HRT) and loading on anaerobic digestion of poultry slaughterhouse wastes, using semi-continuously fed, laboratory-scale digesters at 31 degrees C . The effect on process performance was highly significant: Anaerobic digestion appeared feasible with a loading of up to 0.8 kg volatile solids (VS)/m3 d and an HRT of 50-100 days . The specific methane yield was high, from 0.52 to 0.55 m3/kg VS(added) . On the other hand, at a higher loading, in the range from 1.0 to 2.1 kg VS/m3 d, and a shorter HRT, in the range from 25 to 13 days, the process appeared inhibited and/or overloaded, as indicated by the accumulation of volatile fatty acids and long-chain fatty acids and the decline in the methane yield . However, the inhibition was reversible . The nitrogen in the feed, ca . 7.8% of total solids (TS), was organic nitrogen with little ammonia present, whereas in the digested material ammonia accounted for 52-67% (up to 3.8 g/l) of total nitrogen . The TS and VS removals amounted to 76% and 64%, respectively . Our results show that on a continuous basis under the studied conditions and with a loading of up to 0.8 kg VS/m3 d metric ton (wet weight) of the studied waste mixture could yield up to 140 m3 of methane.

Int Immunopharmacol, 2002 Jun, 2(7), 963 - 73
Selective pharmacological inhibitors reveal the role of Syk tyrosine kinase, phospholipase C, phosphatidylinositol-3'-kinase, and p38 mitogen-activated protein kinase in Fc receptor-mediated signaling of chicken heterophil degranulation; Kogut M et al.; Fc receptors of avian heterophils play a primary role in the elimination of bacterial pathogens in poultry . The cross-linking of Fc receptors with IgG-bacteria complexes results in the secretion of toxic oxygen metabolites and anti-bacterial granules . We have been investigating the upstream signaling events that precede degranulation following crosslinkage of Fc receptors on heterophils . Previously when using the non-selective pharmacological inhibitors genistein, chelerythrine, verapamil, and pertussis toxin, we found no significant inhibitory effects on Fc-mediated heterophil degranulation . In the present studies, we used more selective pharmacological inhibitors to investigate the roles of protein tyrosine kinases, phospholipase C (PLC), phosphatidylinositol 3'-kinase, and the family of mitogen-activated protein kinases (MAPK) on Fc-mediated heterophil degranulation . Inhibitors of the receptor-linked tyrosine kinases (the tryphostins AG 1478 and AG 1296) had no attenuating effects on the Fc receptor-mediated degranulation of chicken heterophils . Likewise, PP2, a selective inhibitor of the Src family of protein tyrosine kinases, had no inhibitory effects on degranulation . However, piceatannol, a selective inhibitor of Syk tyrosine kinase, significantly attenuated the effect of Fc receptor-mediated degranulation . Additionally, Fc-mediated degranulation was significantly attenuated by SB 203580, an inhibitor of p38 MAPK, but not by PD98059, an inhibitor of the extracellular signal-regulated kinase (ERK) . An inhibitor of phospholipase C, U73122 and LY294002, an inhibitor of phosphoinositol-3 kinase significantly decreased heterophil degranulation . These results suggest that the Fc receptors on chicken heterophils, like their counterparts on mammalian neutrophils, have no intrinsic tyrosine kinase activity, but probably mediate downstream events through activation of tyrosine-based activation motifs (ITAM) . Activation of the Syk tyrosine kinase stimulates downstream phosphorylation of p38 MAPK, phospholipase C, and phosphatidylinositol-3 kinase as signaling pathways that regulate Fc-receptor-mediated degranulation of chicken heterophils . Engaging Fc receptors on chicken heterophils activates a Syk-->PLC-->PI3-K-->p38 MAPK signal transduction pathway that induces degranulation.

C R Biol, 2002 May, 325(5), 591 - 6
Does sulphide detoxication occur in the gills of the hydrothermal vent shrimp, Rimicaris exoculata?
Compere P, Martinez AS, Charmantier-Daures M, Toullec JY, Goffinet G, Gaill F.
Ultrastructural observations of the gills of the hydrothermal vent shrimp Rimicaris exoculata reveal that the epithelial cells contain numerous mitochondria clustered around unusual organelles (diameter of 0.7 to 2.5 microns) containing membrane stacks . These organelles were termed sulphide-oxidising bodies (SOBs) by structural analogy with organelles observed in the tissues of species adapted to sulphide-rich environments . Moreover, in the gills of R . exoculata, mitochondria display numerous electron-dense granules in their stroma . Such ultrastructural features suggest that sulphide detoxication may probably occur in the gills of R . exoculata . Comparable structures were also described in the gills of other hydrothermal vent species, as the alvinellid Pompeii worms that, as R . exoculata, are housing ectosymbiotic bacteria.

Ital Heart J Suppl, 2002 Jul, 3(7), 728 - 37
{Surgical correction with homograft in native or prosthetic aortic valve infective endocarditis}; Gamba A et al.; BACKGROUND: Aortic valve surgery for infective endocarditis is still a high-risk procedure and the optimal valve substitute remains controversial . The aim of this study was to evaluate the results of our experience using homografts in the treatment of native (NVE) or prosthetic valve endocarditis (PVE) . METHODS: Between May 1992 and December 2000, 37 patients with NVE and 16 patients with PVE underwent aortic valve replacement with homografts for infective endocarditis . In the two groups of patients the mean age was 57 and 61 years and 38% and 50% were in NYHA functional class IV or V . At the time of surgery, 28 patients had gross vegetations, 23 single or multiple abscess cavities, 3 ventricular septal perforations, and 9 mitral valve endocarditis . Homograft insertion was performed in a subcoronary position in 47 cases and as a root replacement in 6 cases . In 21 cases associated surgical procedures were also performed . RESULTS: Follow-up was 94% complete at a mean of 56 months after valve replacement . There were 1 hospital and 7 delayed deaths; the actuarial survival at 5 years was 85.5 +/- 6% for NVE and 80.8 +/- 10% for PVE . Endocarditis recurred early in 2 cases (both with fungal infection) and late in 3 cases with an endocarditis-free 5-year period of 87.1 +/- 5% . Delayed echocardiography demonstrated aortic incompetence classified as grade II in 40 cases and as grade III and IV in 2 cases . Thirty-nine patients are in NYHA class I and 3 in class II or III . CONCLUSIONS: On the basis of our experience we can conclude that in case of acute endocarditis, if the results of surgery are to be optimized, an early diagnosis and aggressive medical therapy need to be combined with earlier surgical referral . In the presence of NVE without annular abscesses the likelihood of recurrent endocarditis is probably more likely to depend on the infective organism than on the type of valve implanted . Our results support the suggestion that in the presence of NVE with extensive annular abscesses or in case of PVE the homograft valve is the replacement device of choice.

J Cell Sci, 2002 Sep 15, 115(Pt 18), 3703 - 13
RabD, a Dictyostelium Rab14-related GTPase, regulates phagocytosis and homotypic phagosome and lysosome fusion; Harris E et al.; RabD, a Dictyostelium Rab14-related GTPase, localizes in the endo-lysosomal pathway and contractile vacuole system of membranes . Cell lines expressing dominant-negative RabD were defective in endocytosis, endosomal membrane flow and homotypic lysosome fusion . In support of a role for RabD in fusion, cells overexpressing constitutively active RabD(Q67L) accumulated enlarged hydrolase-rich acidic vesicles ringed with GFP-RabD, consistent with RabD directly regulating lysosome fusion . To determine whether RabD also regulated phagocytosis and/or homotypic phagosome fusion (a process stimulated by many intracellular pathogens), cells overexpressing dominant-active (RabD(Q67L)) or dominant-negative (Rab(N121I)) RabD were analyzed microscopically and biochemically . The rate of phagocytosis was increased two-fold in RabD(Q67L)-expressing cells and reduced by 50% in RabD(N121I)-expressing cells compared with control cells . To examine the role of RabD in the formation of multiparticle phagosomes, we performed a series of pulse-chase experiments using fluorescently labeled bacteria and fluorescent latex beads . The rate of fusion of newly formed phagosomes was five times higher in the RabD(Q67L)-expressing cells and reduced by over 50% in RabD(N121I)-expressing cells as compared with control cells . GFP-RabD(Q67L) was found to ring multiparticle spacious phagosomes, which supports a direct role for this protein in regulating fusion . Inhibition of PI 3-kinase activity, which is known to regulate phagosome fusion in the wild-type cells, reduced the rate of phagosome fusion in RabD(Q67L+) cells, indicating that RabD acted upstream of or parallel with PI 3-kinase . We hypothesize that RabD and, possibly, Rab14, a related GTPase that associates with phagosomes in mammalian cells, are important regulators of homotypic phagosome and endo-lysosome fusion.

J Virol, 2002 Sep, 76(18), 9446 - 56
Homomultimerization of the coxsackievirus 2B protein in living cells visualized by fluorescence resonance energy transfer microscopy; van Kuppeveld FJ et al.; The 2B protein of enteroviruses is the viral membrane-active protein that is responsible for the modifications in host cell membrane permeability that take place in enterovirus-infected cells . The 2B protein shows structural similarities to the group of lytic polypeptides, polypeptides that permeate membranes either by forming multimeric membrane-integral pores or, alternatively, by lying parallel to the lipid bilayer and disturbing the curvature and symmetry of the membrane . Our aim is to gain more insight into the molecular architecture of the 2B protein in vivo . In this study, the possible existence of multimers of the coxsackie B3 virus 2B protein in single living cells was explored by fluorescence resonance energy transfer (FRET) microscopy . FRET between fusion proteins 2B-ECFP and 2B-EYFP (enhanced cyan and yellow fluorescent variants of green fluorescent protein) was monitored by using spectral imaging microscopy (SPIM) and fluorescence lifetime imaging microscopy (FLIM) . Both techniques revealed the occurrence of intermolecular FRET between 2B-ECFP and 2B-EYFP, providing evidence for the formation of protein 2B homomultimers . Putative models for the mode of action of the membrane-active 2B protein and the formation of membrane-integral pores by 2B multimers are discussed.

Curr Opin Investig Drugs, 2002 Jul, 3(7), 980 - 6
Vaccines for Chlamydia trachomatis infections; de la Maza LM et al.; Members of the genus, Chlamydia, are obligate intracellular bacteria that have a unique developmental cycle . These organisms are widespread in nature and are common human pathogens . In this review, we describe new data related to the characterization of acquired immunity to Chlamydia trachomatis that is relevant to vaccine development . We also discuss recent work on vaccine candidates against this ubiquitous pathogen.

BMC Pediatr . 2002 Aug 16;2(1):6.
Adenovirus type 7 associated with severe and fatal acute lower respiratory infections in Argentine children; Carballal G et al.; BACKGROUND: Adenoviruses are the second most prevalent cause of acute lower respiratory infection of viral origin in children under four years of age in Buenos Aires, Argentina . The purpose of this study was to analyze the clinical features and outcome of acute lower respiratory infection associated with different adenovirus genotypes in children . METHODS: Twenty-four cases of acute lower respiratory infection and adenovirus diagnosis reported in a pediatric unit during a two-year period were retrospectively reviewed . Adenovirus was detected by antigen detection and isolation in HEp-2 cells . Adenovirus DNA from 17 isolates was studied by restriction enzyme analysis with Bam HI and Sma I . RESULTS: Subgenus b was found in 82.3% of the cases, and subgenus c in 17.7% . Within subgenus b, only genotype 7 was detected, with genomic variant 7h in 85.7% (12/14) and genomic variant 7i in 14.3% (2/14).Mean age was 8.8 +/-; 6 months, and male to female ratio was 3.8: 1 . At admission, pneumonia was observed in 71% of the cases and bronchiolitis in 29% . Malnutrition occurred in 37% of the cases; tachypnea in 79%; chest indrawing in 66%; wheezing in 58%; apneas in 16%; and conjunctivitis in 29% . Blood cultures for bacteria and antigen detection of other respiratory viruses were negative.During hospitalization, fatality rate was 16.7% (4 /24) . Of the patients who died, three had Ad 7h and one Ad 7i . Thus, fatality rate for adenovirus type 7 reached 28.6% (4/14) . CONCLUSIONS: These results show the predominance of adenovirus 7 and high lethality associated with the genomic variants 7h and 7i in children hospitalized with acute lower respiratory infection.

Genome Biol . 2002 Jun 18;3(7):REVIEWS1019 . Epub 2002 Jun 18.
Oxidative stress responses--what have genome-scale studies taught us?
Scandalios JG.
Oxidative stress arises from an imbalance between generation and elimination of reactive oxygen species, often leading to cell death . Genomic tools are expanding our understanding of the antioxidant defenses aerobes have evolved and the recently discovered role(s) of reactive oxygen species in signaling.

Science, 2002 Oct 18, 298(5593), 608 - 11 Epub 2002 Aug 15.
Role of predicted metalloprotease motif of Jab1/Csn5 in cleavage of Nedd8 from Cul1; Cope GA et al.; COP9 signalosome (CSN) cleaves the ubiquitin-like protein Nedd8 from the Cul1 subunit of SCF ubiquitin ligases . The Jab1/MPN domain metalloenzyme (JAMM) motif in the Jab1/Csn5 subunit was found to underlie CSN's Nedd8 isopeptidase activity . JAMM is found in proteins from archaea, bacteria, and eukaryotes, including the Rpn11 subunit of the 26S proteasome . Metal chelators and point mutations within JAMM abolished CSN-dependent cleavage of Nedd8 from Cul1, yet had little effect on CSN complex assembly . Optimal SCF activity in yeast and both viability and proper photoreceptor cell (R cell) development in Drosophila melanogaster required an intact Csn5 JAMM domain . We propose that JAMM isopeptidases play important roles in a variety of physiological pathways.

Science, 2002 Aug 16, 297(5584), 1151 - 4
Direct evidence for a marine source of C1 and C2 alkyl nitrates; Chuck AL et al.; Alkyl nitrates are a significant component of the "odd nitrogen" reservoir and play an important role in regulating tropospheric ozone levels in remote marine regions . Measurements of methyl and ethyl nitrate in seawater and air samples along two Atlantic Ocean transects provide the first direct evidence for an oceanic source of these compounds . Equatorial surface waters were highly supersaturated (up to 800%) in both species, with the waters in the temperate regions generally being closer to equilibrium . A simple box model calculation suggests that the equatorial source could be a major component of the local atmospheric alkyl nitrate budget.

Science, 2002 Aug 16, 297(5584), 1137 - 42
Proterozoic ocean chemistry and evolution: a bioinorganic bridge?
Anbar AD, Knoll AH.
Recent data imply that for much of the Proterozoic Eon (2500 to 543 million years ago), Earth's oceans were moderately oxic at the surface and sulfidic at depth . Under these conditions, biologically important trace metals would have been scarce in most marine environments, potentially restricting the nitrogen cycle, affecting primary productivity, and limiting the ecological distribution of eukaryotic algae . Oceanic redox conditions and their bioinorganic consequences may thus help to explain observed patterns of Proterozoic evolution.

Infect Immun, 2002 Sep, 70(9), 5295 - 8
Differential expression of the p44 gene family in the agent of human granulocytic ehrlichiosis; IJdo JW et al.; Using reverse transcription-PCR targeting of the p44 genes of the agent of human granulocytic ehrlichiosis (HGE) with primers flanking the hypervariable region, we show differential expression in a murine model of HGE infection and during tick transmission . The p44 genes were differentially expressed in salivary glands of infected nymphal ticks removed during transmission feeding but not in nonfeeding infected ticks . Similarly, the p44 genes were differentially expressed in infected C3H mice, in SCID mice, and in cultured HGE bacteria . Thus, differential p44 expression exists in vivo and in vitro and could provide a basis for antigenic variation.

Infect Immun, 2002 Sep, 70(9), 5140 - 7
Nitric oxide inhibits Coxiella burnetii replication and parasitophorous vacuole maturation; Howe D et al.; Nitric oxide is a recognized cytotoxic effector against facultative and obligate intracellular bacteria . This study examined the effect of nitric oxide produced by inducible nitric oxide synthase (iNOS) up-regulated in response to cytokine stimulation, or by a synthetic nitric oxide donor, on replication of obligately intracellular Coxiella burnetii in murine L-929 cells . Immunoblotting and nitrite assays revealed that C . burnetii infection of L-929 cells augments expression of iNOS up-regulated in response to gamma interferon (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) . Infection in the absence of cytokine stimulation did not result in demonstrable up-regulation of iNOS expression or in increased nitrite production . Nitrite production by cytokine-treated cells was significantly inhibited by the iNOS inhibitor S-methylisothiourea (SMT) . Treatment of infected cells with IFN-gamma and TNF-alpha or the synthetic nitric oxide donor 2,2'-(hydroxynitrosohydrazino)bis-ethanamine (DETA/NONOate) had a bacteriostatic effect on C . burnetii replication . Inhibition of replication was reversed upon addition of SMT to the culture medium of cytokine-treated cells . Microscopic analysis of infected cells revealed that nitric oxide (either cytokine induced or donor derived) inhibited formation of the mature (large) parasitophorous vacuole that is characteristic of C . burnetii infection of host cells . Instead, exposure of infected cells to nitric oxide resulted in the formation of multiple small, acidic vacuoles usually containing one C . burnetii cell . Removal of nitrosative stress resulted in the coalescence of small vacuoles to form a large vacuole harboring multiple C . burnetii cells . These experiments demonstrate that nitric oxide reversibly inhibits replication of C . burnetii and formation of the parasitophorous vacuole.

J Biol Chem, 2002 Oct 25, 277(43), 40290 - 5 Epub 2002 Aug 14.
Interactions of inositol 1,4,5-trisphosphate (IP(3)) receptors with synthetic poly(ethylene glycol)-linked dimers of IP(3) suggest close spacing of the IP(3)-binding sites; Riley AM et al.; The distances between the inositol 1,4,5-trisphosphate (IP(3))-binding sites of tetrameric IP(3) receptors were probed using dimers of IP(3) linked by poly(ethylene glycol) (PEG) molecules of differing lengths (1-8 nm) . Each of the dimers potently stimulated (45)Ca(2+) release from permeabilized cells expressing predominantly type 1 (SH-SY5Y cells) or type 2 (hepatocytes) IP(3) receptors . The shortest dimers, with PEG linkers of an effective length of 1.5 nm or less, were the most potent, being 3-4-fold more potent than IP(3) . In radioligand binding experiments using cerebellar membranes, the shortest dimers bound with highest affinity, although the longest dimer (8 nm) also bound with almost 4-fold greater affinity than IP(3) . The affinity of monomeric IP(3) with only the PEG attached was 2-fold weaker than IP(3), confirming that the increased affinity of the dimers requires the presence of both IP(3) motifs . The increased affinity of the long dimer probably results from the linked IP(3) molecules binding to sites on different receptors, because the dimer bound with greater affinity than IP(3) to cerebellar membranes, where receptors are densely packed, but with the same affinity as IP(3) to purified receptors . IP(3) and the IP(3) dimers, irrespective of their length, bound with similar affinity to a monomeric IP(3)-binding domain of the type 1 IP(3) receptor expressed in bacteria . Short dimers therefore bind with increased affinity only when the receptor is tetrameric . We conclude that the four IP(3)-binding sites of an IP(3) receptor may be separated by as little as 1.5 nm and are therefore likely to be placed centrally in this large (25 x 25 nm) structure, consistent with previous work indicating a close association between the central pore and the IP(3)-binding sites of the IP(3) receptor.

BMJ . 2002 Aug 17;325(7360):362.
Efficacy of handrubbing with alcohol based solution versus standard handwashing with antiseptic soap: randomised clinical trial; Girou E et al.; OBJECTIVE: To compare the efficacy of handrubbing with an alcohol based solution versus conventional handwashing with antiseptic soap in reducing hand contamination during routine patient care . DESIGN: Randomised controlled trial during daily nursing sessions of 2 to 3 hours . SETTING: Three intensive care units in a French university hospital . PARTICIPANTS: 23 healthcare workers . INTERVENTIONS: Handrubbing with alcohol based solution (n=12) or handwashing with antiseptic soap (n=11) when hand hygiene was indicated before and after patient care . Imprints taken of fingertips and palm of dominant hand before and after hand hygiene procedure . Bacterial counts quantified blindly . MAIN OUTCOME MEASURES: Bacterial reduction of hand contamination . RESULTS: With handrubbing the median percentage reduction in bacterial contamination was significantly higher than with handwashing (83% v 58%, P=0.012), with a median difference in the percentage reduction of 26% (95% confidence interval 8% to 44%) . The median duration of hand hygiene was 30 seconds in each group . CONCLUSIONS: During routine patient care handrubbing with an alcohol based solution is significantly more efficient in reducing hand contamination than handwashing with antiseptic soap.

J Pharmacol Toxicol Methods, 2001 Nov-Dec, 46(3), 169 - 72
An improvement of the Ames test using a modified human liver S9 preparation; Hakura A et al.; INTRODUCTION: In preliminary studies on the Ames test using human liver S9 fractions, we found that the crude human S9 fractions, obtained following centrifugation of the tissue homogenate for 20 min at 9000 x g, were not always sterile . When this was the case, the S9 fractions were often accompanied by an increased number of colonies above the normal range on plates in the solvent control used in the Ames test . In addition, we also sometimes identified the incorporation of a small amount of fat in the crude human liver S9 fractions . We have therefore obtained a purified fat-free S9 fraction by a simple modification to the crude S9 preparation; fat was completely removed by centrifugation of the crude S9 fraction . METHODS: Using the purified and crude human S9 fractions (two lots each), both the sterility and the number of bacterial colonies produced on a plate with five bacterial tester strains by solvent controls (purified water and dimethyl sulfoxide) were examined . The findings were then compared to those observed with phosphate buffer or S9 fraction from rats pretreated with phenobarbital/5,6-benzoflavone . RESULTS: The data show that each of the crude human S9 fractions was not sterile and produced an increasing number of colonies with each solvent control, almost equal to the sum of the numbers of contaminating bacterial colonies and spontaneous revertant colonies observed with phosphate buffer or the rat S9 fraction . On the other hand, both the purified human S9 fractions were sterile, and the number of colonies that appeared in each solvent control was similar to that of spontaneous revertant colonies observed with phosphate buffer or the rat S9 fraction . DISCUSSION: These results indicate that this new procedure of S9 preparation, modified with an additional recentrifugation step, may provide a high quality of purified fat- and bacteria-free S9 fraction for use in the Ames test.

Protein Expr Purif, 2002 Aug, 25(3), 456 - 64
Preparation and expression of biologically active prolactin and growth hormone receptors and suppressor of cytokine signaling proteins 1, 2, 3, and 6 tagged with cyan and yellow fluorescent proteins; Ben-Yair L et al.; To prepare reagents for a study of the interactions of prolactin (PRL) and growth hormone (GH) receptors (Rs) with suppressor of cytokine signaling (SOCS) proteins in living cells by fluorescence resonance energy transfer methodology, the respective proteins were tagged with cyan (CFP) or yellow (YFP) fluorescent protein . Constructs encoding ovine (o)PRLR-YFP, oPRLR-CFP, oGHR-YFP, and oGHR-CFP tagged downstream of the receptor DNA were prepared in the plasmid pcDNA plasmid and tested for biological activity in HEK 293T cells transiently cotransfected with those constructs and the reporter gene encoding luciferase . All four constructs were biologically active and as potent as their untagged counterparts . Cells transfected with those proteins exhibited fluorescence in the cytoplasm and the membrane . Constructs encoding DNA tagged with YFP or CFP upstream of SOCS1, SOCS2, SOCS3, and SOCS6 were prepared in pECFP-C1 and pEYFP-C1 plasmids . The biological activities of SOCS1 and SOCS3 tagged at their amino termini were assayed by their ability to inhibit placental lactogen (PL)- or GH-induced activation of JAK2/STAT5-mediated luciferase transcription in HEK 293T cells; the activity of SOCS2 was assayed by its ability to abolish SOCS1-induced inhibition . The tagged proteins exhibited biological activity that was equal to or even more potent than their untagged counterparts . The biological activities of CFP-SOCS2 and YFP-SOCS2 were also assayed using GST-GHR binding assay . Their interaction with the cytosolic domain of GHR was equivalent to their respective untagged counterparts . The biological activity of the construct encoding SOCS6 was not tested because of lack of a suitable assay . Cells transfected with eight of these tagged constructs expressed the fluorescent proteins in both the nucleus and cytosol; the tagged SOCS2 was localized mostly in the latter compartment.

Aliment Pharmacol Ther, 2002 Aug, 16(8), 1383 - 93
The role of the gut flora in health and disease, and its modification as therapy; Hart AL et al.; The gut flora is a vast interior ecosystem whose nature is only beginning to be unravelled, due to the emergence of sophisticated molecular tools . Techniques such as 16S ribosomal RNA analysis, polymerase chain reaction amplification and the use of DNA microarrays now facilitate rapid identification and characterization of species resistant to conventional culture and possibly unknown species . Life-long cross-talk between the host and the gut flora determines whether health is maintained or disease intervenes . An understanding of these bacteria-bacteria and bacteria-host immune and epithelial cell interactions is likely to lead to a greater insight into disease pathogenesis . Studies of single organism-epithelial interactions have revealed the large range of metabolic processes that gut bacteria may influence . In inflammatory bowel diseases, bacteria drive the inflammatory process, and genetic predisposition to disease identified to date, such as the recently described NOD2/CARD15 gene variants, may relate to altered bacterial recognition . Extra-intestinal disorders, such as atopy and arthritis, may also have an altered gut milieu as their basis . Clinical evidence is emerging that the modification of this internal environment, using either antibiotics or probiotic bacteria, is beneficial in preventing and treating disease . This natural and apparently safe approach holds great appeal.

Plant J, 2002 Aug, 31(4), 487 - 97
A novel interaction partner for the C-terminus of Arabidopsis thaliana plasma membrane H+-ATPase (AHA1 isoform): site and mechanism of action on H+-ATPase activity differ from those of 14-3-3 proteins; Morandini P et al.; Using the two-hybrid technique we identified a novel protein whose N-terminal 88 amino acids (aa) interact with the C-terminal regulatory domain of the plasma membrane (PM) H+-ATPase from Arabidopsis thaliana (aa 847-949 of isoform AHA1) . The corresponding gene has been named Ppi1 for Proton pump interactor 1 . The encoded protein is 612 aa long and rich in charged and polar residues, except for the extreme C-terminus, where it presents a hydrophobic stretch of 24 aa . Several genes in the A . thaliana genome and many ESTs from different plant species share significant similarity (50-70% at the aa level over stretches of 200-600 aa) to Ppi1 . The PPI1 N-terminus, expressed in bacteria as a fusion protein with either GST or a His-tag, binds the PM H+-ATPase in overlay experiments . The same fusion proteins and the entire coding region fused to GST stimulate H+-ATPase activity . The effect of the His-tagged peptide is synergistic with that of fusicoccin (FC) and of tryptic removal of a C-terminal 10 kDa fragment . The His-tagged peptide binds also the trypsinised H+-ATPase . Altogether these results indicate that PPI1 N-terminus is able to modulate the PM H+-ATPase activity by binding to a site different from the 14-3-3 binding site and is located upstream of the trypsin cleavage site.

Pediatr Infect Dis J, 2002 Jun, 21(6), 505 - 11
Variations in central venous catheter-related infection risks among Canadian neonatal intensive care units; Chien LY et al.; BACKGROUND: The objective of this study was to examine central venous catheter (CVC)-related nosocomial blood stream infection risks of umbilical venous, percutaneous and Broviac catheters, as well as variations in CVC use and CVC-related risk for nosocomial blood stream infection in the neonatal intensive care unit (NICU) . METHODS: A cohort study was performed based on 19,507 infants admitted to 17 NICUs in the Canadian Neonatal Network from January, 1996, through October, 1997 . Information on these subjects was prospectively collected by trained abstractors . Incidence of infection was measured as infection episodes per 1000 patient days . The risk ratio (RR) of CVC use for nosocomial blood stream infection was calculated as the infection rate during catheter days divided by the infection rate during noncatheter days . Using a Poisson regression model we examined the adjusted RR of CVC use for nosocomial blood stream infection, controlling for patient characteristics and illness severity at admission . Interinstitutional variations in CVC-related infection risks were examined by stratified analyses . RESULTS: CVC were used in 22.5% of patients . The incidence of nosocomial blood stream infection was 2.9 per 1000 noncatheter days, 7.2 per 1000 umbilical venous catheter days, 13.1 per 1000 percutaneous catheter days and 12.1 per 1000 Broviac catheter days . The RR for nosocomial blood stream infection, adjusted for differences in patient characteristics and admission illness severity, was 2.5 for umbilical venous catheter, 4.6 for percutaneous catheter and 4.3 for Broviac catheter (P < 0.05) . There were significant (P < 0.05) risk-adjusted variations in CVC-related infection risks among NICUs . CONCLUSIONS: CVC use increased the risk of nosocomial blood stream infection . The risk of nosocomial blood stream infection in percutaneous and Broviac catheters was 70 to 80% higher than in umbilical venous catheters . There was significant variation in CVC-related infection risks among Canadian NICUs.

Mol Pharmacol, 2002 Sep, 62(3), 672 - 9
Activation of phospholipase Cgamma2 by tyrosine phosphorylation; Ozdener F et al.; Phospholipase Cgamma2 (PLCgamma2) has been implicated in collagen-induced signal transduction in platelets and antigen-dependent signaling in B-lymphocytes . It has been suggested that tyrosine kinases activate PLCgamma2 . We expressed the full-length cDNA for human PLCgamma2 in bacteria and purified the recombinant enzyme . The recombinant enzyme was Ca(2+)-dependent with optimal activity in the range of 1 to 10 microM Ca(2+) . In vitro phosphorylation experiments with recombinant PLCgamma2 and recombinant Lck, Fyn, and Lyn tyrosine kinases showed that phosphorylation of PLCgamma2 led to activation of the recombinant enzyme . Using site-directed mutagenesis, we investigated the role of specific tyrosine residues in activation of PLCgamma2 . A mutant form of PLCgamma2, in which all three tyrosines at positions 743, 753, and 759 in the SH2-SH3 linker region were replaced by phenylalanines, exhibited decreased Lck-induced phosphorylation and completely abolished the Lck-dependent activation of PLCgamma2 . Individual mutations of these tyrosine residues demonstrated that tyrosines 753 and 759, but not 743, were responsible for Lck-induced activation of PLCgamma2 . To confirm these results, we procured a phosphospecific antibody to a peptide containing phosphorylated tyrosines corresponding to residues 753 and 759 . This antibody recognized phosphorylated wild-type PLCgamma2 on Western blots but did not interact with unphosphorylated PLCgamma2 or with PLCgamma2 containing mutated tyrosine residues at 753 and 759 . Using this antibody, we showed in intact platelets that collagen, a PLCgamma2-dependent agonist, induces phosphorylation of PLCgamma2 at Y753 and Y759 . These studies demonstrate the importance of these two tyrosine residues in regulating the activity of PLCgamma2.

J Microsc, 2002 Aug, 207(Pt 2), 97 - 107
Iso-butanol saturated water: a simple procedure for increasing staining intensity of resin sections for light and electron microscopy; Roberts IM; The addition of the alcohol iso-butanol (2-methylpropan-1-ol) to water was found to improve the post-staining procedures for semi-thin and ultrathin resin sections, for both light and electron microscopy . Stain penetration was enhanced with samples embedded in both acrylic and epoxy resins and provided structural information not previously seen . These improvements were found with general (non-specific) stains and a fluorescence stain for light microscopy, as well as for a range of heavy metal stains for electron microscopy . The use of this water/solvent medium also gave improved results when used in a variety of immunogold labelling procedures, resulting in a greater specific label density without affecting background gold levels . The use of this solvent/water medium may have wider applications for other types of staining.

Life Sci Space Res, 1975, 13, 75 - 82
Some considerations of the theoretical limits for living organisms; Sneath PH; The study of the limits of life has been traditionally divided into two parts (a) extreme conditions for growth and metabolism, and (b) those conditions permitting survival in a dormant state . The variables most often considered have been temperature, radiation, availability of water and ageing . For growth and metabolism the most sensitive parts of living organisms appear to be those that involve labile metabolites, of which there is a great variety . For dormancy the stability of covalent bonds seems most important; here the C-C bond is likely to be less significant than C-O and C-N . But for both classes of damage the stability greatly depends on numerous factors (such as pH and oxygen concentration) that have seldom been considered in work so far . It is therefore desirable to explore the effects of combinations of adverse factors upon key metabolites and macromolecules . In addition, such studies may permit better estimates of the effects of very long time periods by extrapolation from experimental work.

Curr Opin Biotechnol, 2002 Jun, 13(3), 253 - 61
Low-temperature extremophiles and their applications; Cavicchioli R et al.; Psychrophilic (cold-adapted) organisms and their products have potential applications in a broad range of industrial, agricultural and medical processes . In order for growth to occur in low-temperature environments, all cellular components must adapt to the cold . This fact, in combination with the diversity of Archaea, Bacteria and Eucarya isolated from cold environments, highlights the breadth and type of biological products and processes that might be exploited for biotechnology . Relative to this undisputed potential, psychrophiles and their products are under-utilised in biotechnology; however, recent advances, particularly with cold-active enzymes, herald rapid growth for this burgeoning field.

Heredity, 2002 Jun, 88(6), 444 - 9
Feminizing Wolbachia in an insect, Ostrinia furnacalis (Lepidoptera: Crambidae); Kageyama D et al.; Wolbachia, which forms a group of maternally inherited bacteria in arthropods, often cause reproduction alterations in their hosts, such as cytoplasmic incompatibility, parthenogenesis, male-killing, hybrid breakdown and feminization . To date, Wolbachia-induced feminization has been reported only in isopods . Here we report that a Wolbachia strain feminizes an insect host, Ostrinia furnacalis . Among 79 wild females of O . furnacalis examined, Wolbachia infection was detected in 13 females . Twelve of the 13 infected females produced all-female progenies, and this trait was maternally inherited . Tetracycline treatment of thelygenic matrilines resulted in the production of all-male progenies . The present findings indicate that the Wolbachia infection induces feminization of genetic males in O . furnacalis . Differences in the Wolbachia-induced feminization in O . furnacalis and that in isopods are discussed along with the differences in sex determination mechanisms between insects and isopods . Phylogenetic analysis of the wsp gene sequence of Wolbachia suggests independent evolutionary origins for the Wolbachia-induced feminizations in O . furnacalis and in isopods . Our findings over 5 years suggest that the infection has been maintained at a low prevalence in the O . furnacalis population.

Dly Times . 1992 Sep 10;:7.
Allaying the fears in the use of intrauterine devices; Ibekwe J; PIP: Women's perceptions of the hazards of birth control devices centers on fears of sterility from IUD use and the permanence of bilateral tubal ligation . In March, 1992, an International Conference on the IUD gathered scientists and physicians from around the world to compare and contrast research findings on the risk and benefits of IUD use . Scientific examination pertained to IUD clinical performance, mechanisms of action, medical problems and their prevention, ectopic pregnancy, infertility, and post removed conception rates . Some of the findings were summarized . 1) The copper T 380 was recommended by WHO, because of the very low pregnancy rates, the long duration and relative ease of use, and low manufacturing costs . 2) IUD users, who are at low risk of contracting sexually transmitted diseases (STDs), do not have an elevated risk of pelvic inflammatory diseases (PID) due to use . Those who have multiple partners are strongly advised to use other forms of contraception . 3) Pregnancy rates are high after discontinuation; 80% conceive in the first year, and 90% within 2 years . 4) The mechanism of action is to decrease the number of viable sperm and interfere with egg transport, before the fertilization process . 5) The monofilament string is not associated with an increased risk of PID; PID is related to introduction of bacteria during insertion . 6) The IUD may be unsuitable in areas with high prevalence of STDs and/or anemia; screening may present a challenge . In areas with poor infrastructure, IUD use can be optimized by improving method selection and providing interventions for those who may develop problems . consensus was very high that all women planning IUD use should be screened for risk of infections that could lead to PID . Clients would need to be interviewed about their own sexual behavior and the behavior of their male partners . If programs are not capable of identifying women at risk or testing and treating STDs, the IUD should either not be used or be used only if incidence of venereal disease is low .

Microbiology, 2002 Aug, 148(Pt 8), 2557 - 65
Conflicting phylogeographic patterns in rRNA and nifD indicate regionally restricted gene transfer in Bradyrhizobium; Parker MA et al.; Major differences in evolutionary relationships of the 16S rRNA gene and the nitrogenase alpha-subunit gene (nifD) were observed among 38 strains of Bradyrhizobium sp . nodule bacteria from North America, Central America, Asia and Australia . Two lineages were evident in the 16S rRNA phylogeny representing strains related to Bradyrhizobium japonicum (29 isolates) or Bradyrhizobium elkanii (9 isolates) . Both clades were distributed across most or all of the geographic regions sampled . By contrast, in the nifD tree almost all isolates were placed into one of three groups each exclusively composed of taxa from a single geographic region (North Temperate, Central America or Australia) . Isolates that were closely related or identical in gene sequence at one locus often had divergent sequences at the other locus and a partition homogeneity test indicated that the 16S rRNA and nifD phylogenies were significantly incongruent . No evidence for any gene duplication of nifD was found by Southern hybridization analysis on a subset of the strains, so unrecognized paralogy is not likely to be responsible for the discrepancy between 16S rRNA and nifD tree topologies . These results are consistent with a model whereby geographic areas were initially colonized by several diverse 16S rRNA lineages, with subsequent horizontal gene transfer of nifD leading to increased nifD sequence homogeneity within each regional population.

Microbiology, 2002 Aug, 148(Pt 8), 2541 - 9
Protein signatures distinctive of chlamydial species: horizontal transfers of cell wall biosynthesis genes glmU from archaea to chlamydiae and murA between chlamydiae and Streptomyces; Griffiths E et al.; Chlamydiae are major human and animal pathogens . Based on alignments of different protein sequences, a number of conserved indels (insertion/deletions) were identified that appear to be unique and distinctive characteristics of the chlamydial species . The identified signatures include one 16 aa and two single aa inserts in the enzyme UDP-N-acetylglucosamine 1-carboxyvinyltransferase (MurA), a 1 aa insert in protein synthesis elongation factor P (EF-P), a 1 aa insert in the Mg(2+) transport protein (MgtE), a 1 aa insert in the carboxy-terminal protease and a 1 aa deletion in the tRNA (guanine-N(1)-)-methyltransferase (TrmD) protein . The homologues of these proteins are found in all major groups of bacteria and the observed indels are present in all available chlamydial sequences but not in any other species (except for the large insert in MurA in Streptomyces) . The validity of three of these signatures (MurA, EF-P and MgtE) was tested by PCR amplifying the signature regions from several chlamydial species for which no sequence information was available . All Chlamydiaceae species for which specific fragments could be amplified (Chlamydia suis, Chlamydophila abortus, Chlamydophila psittaci, Chlamydophila felis) contained the expected signatures . Additionally, a fragment of the murA gene from Waddlia chondrophila and the efp gene from Simkania negevensis, two chlamydia-like species, were also cloned and sequenced . The presence of respective indels in these species provides strong evidence that they are specifically related to the traditional chlamydial species, and that these signatures may be distinctive of the entire Chlamydiales order . A 17 aa conserved indel was also identified in the cell wall biosynthesis enzyme UDP-N-acetylglucosamine pyrophosphorylase (GlmU), which is shared by all archaeal and chlamydial homologues . The gene for this protein is indicated to have been horizontally transferred from an archaeon to a common ancestor of the chlamydiae . The results also support a lateral transfer of the murA gene between chlamydiae and STREPTOMYCES: The large inserts in these peptidoglycan synthesis related genes in chlamydiae could account for their unusual cell-wall characteristics . These signatures are also potentially useful for screening of the chlamydiae species.

Microbiology, 2002 Aug, 148(Pt 8), 2497 - 505
Diversity within inc genes of clinical Chlamydia trachomatis variant isolates that occupy non-fusogenic inclusions; Rockey DD et al.; The obligately intracellular chlamydiae are bacterial pathogens that occupy intracellular vacuoles, termed inclusions, as they develop and multiply . Typical Chlamydia trachomatis isolates occupy inclusions that fuse with other C . trachomatis inclusions within cells infected with multiple elementary bodies (wild-type phenotype) . The authors of this study have recently described C . trachomatis isolates that form multiply-lobed, non-fusogenic inclusions within single cells infected with multiple elementary bodies (variant phenotype) . Inclusions formed by these isolates uniformly lacked the protein IncA on the inclusion membrane (IM) . In the present work, the study of the C . trachomatis inclusion phenotype has been expanded to include 27 variant and 13 wild-type isolates . Twenty-four of the 27 variant isolates were IncA-negative, as detected by fluorescence microscopy and immunoblotting, but three variants localized IncA to the IM . The IncA-positive variants formed inclusions that fused, at a reduced rate, with those occupied by wild-type isolates and with inclusions formed by other IncA-positive variants . Nucleotide-sequence analysis of the incA sequences from the variant isolates identified a variety of distinct sequence polymorphisms relative to incA from wild-type strains . The authors also demonstrate that a second Inc protein, CT223p, is not found in the IM in selected C . trachomatis isolates . No change in the structure or the fusogenicity of the inclusions was associated with the presence or absence of CT223p.

Microbiology, 2002 Aug, 148(Pt 8), 2489 - 95
Differential effects of Kid toxin on two modes of replication of lambdoid plasmids suggest that this toxin acts before, but not after, the assembly of the replication complex; Potrykus K et al.; Kid is a small protein that is encoded by plasmid R1 . It is a toxin that belongs to a killer system that ensures the stability of the plasmid in host cells . The results of previous studies have suggested that Kid is an inhibitor of DNA replication, possibly acting at the onset of initiation . Here, the authors tested the effects of Kid on orilambda-intitiated and oriJ-initiated replication, which may be driven by both the newly assembled replication complex and the heritable complex . It was found that Kid inhibits only replication that is driven by the newly assembled replication complex . The authors also report that Kid inhibits ColE1-like plasmid replication in vivo, in agreement with the previously reported inhibition of ColE1 during in vitro replication . It is proposed that the Kid toxin acts at the level of replication either by preventing de novo assembly of the replication complex or by impairing the functional interactions of the replication complex at the initiation stage.

Microbiology, 2002 Aug, 148(Pt 8), 2427 - 37
A zinc metalloprotease inhibitor, Inh, from the insect pathogen Photorhabdus luminescens; Valens M et al.; The entomopathogen Photorhabdus luminescens secretes many proteins during the late stages of insect larvae infection and during in vitro laboratory culture . The authors have previously characterized and purified a 55 kDa zinc metalloprotease, PrtA, from culture supernatants of P . luminescens . PrtA is secreted via a classical type I secretory pathway and is encoded within the operon prtA-inh-prtBCD . The 405 bp inh gene encodes a 14.8 kDa pre-protein that is translocated to the periplasm by the classical signal-peptide-dependent sec pathway, yielding the mature 11.9 kDa inhibitor Inh . Inh is a specific inhibitor of the protease PrtA . This study describes the purification of Inh and the initial characterization of its in vitro protease inhibition properties.

Microbiology, 2002 Aug, 148(Pt 8), 2293 - 8
Evidence for protection of nitrogenase from O(2) by colony structure in the aerobic diazotroph Gluconacetobacter diazotrophicus; Dong Z et al.; Gluconacetobacter diazotrophicus is an endophytic diazotroph of sugarcane which exhibits nitrogenase activity when growing in colonies on solid media . Nitrogenase activity of G . diazotrophicus colonies can adapt to changes in atmospheric partial pressure of oxygen (pO(2)) . This paper investigates whether colony structure and the position of G . diazotrophicus cells in the colonies are components of the bacterium's ability to maintain nitrogenase activity at a variety of atmospheric pO(2) values . Colonies of G . diazotrophicus were grown on solid medium at atmospheric pO(2) of 2 and 20 kPa . Imaging of live, intact colonies by confocal laser scanning microscopy and of fixed, sectioned colonies by light microscopy revealed that at 2 kPa O(2) the uppermost bacteria in the colony were very near the upper surface of the colony, while the uppermost bacteria of colonies cultured at 20 kPa O(2) were positioned deeper in the mucilaginous matrix of the colony . Disruption of colony structure by physical manipulation or due to 'slumping' associated with colony development resulted in significant declines in nitrogenase activity . These results support the hypothesis that G . diazotrophicus utilizes the path-length of colony mucilage between the atmosphere and the bacteria to achieve a flux of O(2) that maintains aerobic respiration while not inhibiting nitrogenase activity.

Nucleic Acids Res, 2002 Aug 15, 30(16), 3592 - 601
Metallo-beta-lactamase fold within nucleic acids processing enzymes: the beta-CASP family; Callebaut I et al.; A separate family of enzymes within the metallo-beta-lactamase fold comprises several important proteins acting on nucleic acid substrates, involved in DNA repair (Artemis, SNM1 and PSO2) and RNA processing {cleavage and polyadenylation specificity factor (CPSF) subunit} . Proteins of this family, named beta-CASP after the names of its representative members, possess specific features relative to those of other metallo-beta-lactamases, that are concentrated in the C-terminal part of the domain . In this study, using sensitive methods of sequence analysis, we identified highly conserved amino acids specific to the beta-CASP family, some of which were unidentified to date, that are predicted to play critical roles in the enzymatic function . The identification and characterisation of all the extant, detectable beta-CASP members within sequence databases and genome data also allowed us to unravel particular sequence features which are likely to be involved in substrate specificity, as well as to describe new but as yet uncharacterised members which may play critical roles in DNA and RNA metabolism.

J Exp Bot, 2002 Sep, 53(376), 1991 - 3
The novel rice (Oryza sativa L.) gene OsSbf1 encodes a putative member of the Na+/bile acid symporter family; Rzewuski G et al.; PCR-based differential screening was used to identify ethylene-induced genes in deep-water rice (Oryza sativa L.) . One of the isolated cDNAs represented a novel protein, OsSBF1, with high homology to mammalian Na+/bile acid transporters and to sodium-dependent transporters from bacteria . One highly homologous protein and three less conserved homologues were identified in Arabidopsis thaliana indicating that Sbf proteins exist in monocot and dicot plant species . Expression of OsSbf1 in deep-water rice was shown to be elevated by growth-inducing treatments . Since bile acids have not been found in plants to date a possible function of SBF proteins may be in the transport of structurally related sulphonated brassinosteroids.

J Cell Biol, 2002 Aug 19, 158(4), 625 - 37 Epub 2002 Aug 12.
The 2 micron plasmid purloins the yeast cohesin complex: a mechanism for coupling plasmid partitioning and chromosome segregation?
Mehta S, Yang XM, Chan CS, Dobson MJ, Jayaram M, Velmurugan S.
The yeast 2 micron plasmid achieves high fidelity segregation by coupling its partitioning pathway to that of the chromosomes . Mutations affecting distinct steps of chromosome segregation cause the plasmid to missegregate in tandem with the chromosomes . In the absence of the plasmid stability system, consisting of the Rep1 and Rep2 proteins and the STB DNA, plasmid and chromosome segregations are uncoupled . The Rep proteins, acting in concert, recruit the yeast cohesin complex to the STB locus . The periodicity of cohesin association and dissociation is nearly identical for the plasmid and the chromosomes . The timely disassembly of cohesin is a prerequisite for plasmid segregation . Cohesin-mediated pairing and unpairing likely provides a counting mechanism for evenly partitioning plasmids either in association with or independently of the chromosomes.

J Biol Chem, 2002 Oct 18, 277(42), 40106 - 11 Epub 2002 Aug 09.
Accumulation of 99Mo-containing iron-molybdenum cofactor precursors of nitrogenase on NifNE, NifH, and NifX of Azotobacter vinelandii; Rangaraj P et al.; The biosynthesis of the iron-molybdenum cofactor (FeMo-co) of nitrogenase was investigated using the purified in vitro FeMo-co synthesis system and 99Mo . The purified system involves the addition of all components that are known to be required for FeMo-co synthesis in their purified forms . Here, we report the accumulation of a 99Mo-containing FeMo-co precursor on NifNE . Apart from NifNE, NifH and NifX also accumulate 99Mo label . We present evidence that suggests NifH may serve as the entry point for molybdenum incorporation into the FeMo-co biosynthetic pathway . We also present evidence suggesting a role for NifX in specifying the organic acid moiety of FeMo-co.

Genome Res, 2002 Aug, 12(8), 1159 - 67
Evidence that plant-like genes in Chlamydia species reflect an ancestral relationship between Chlamydiaceae, cyanobacteria, and the chloroplast; Brinkman FS et al.; An unusually high proportion of proteins encoded in Chlamydia genomes are most similar to plant proteins, leading to proposals that a Chlamydia ancestor obtained genes from a plant or plant-like host organism by horizontal gene transfer . However, during an analysis of bacterial-eukaryotic protein similarities, we found that the vast majority of plant-like sequences in Chlamydia are most similar to plant proteins that are targeted to the chloroplast, an organelle derived from a cyanobacterium . We present further evidence suggesting that plant-like genes in Chlamydia, and other Chlamydiaceae, are likely a reflection of an unappreciated evolutionary relationship between the Chlamydiaceae and the cyanobacteria-chloroplast lineage . Further analyses of bacterial and eukaryotic genomes indicates the importance of evaluating organellar ancestry of eukaryotic proteins when identifying bacteria-eukaryote homologs or horizontal gene transfer and supports the proposal that Chlamydiaceae, which are obligate intracellular bacterial pathogens of animals, are not likely exchanging DNA with their hosts.

Bioinformatics, 2002 Aug, 18(8), 1021 - 33
Why are complementary DNA strands symmetric?
Baisnee PF, Hampson S, Baldi P.
MOTIVATION: Over sufficiently long windows, complementary strands of DNA tend to have the same base composition . A few reports have indicated that this first-order parity rule extends at higher orders to oligonucleotide composition, at least in some organisms or taxa . However, the scientific literature falls short of providing a comprehensive study of reverse-complement symmetry at multiple orders and across the kingdom of life . It also lacks a characterization of this symmetry and a convincing explanation or clarification of its origin . RESULTS: We develop methods to measure and characterize symmetry at multiple orders, and analyze a wide set of genomes, encompassing single- and double-stranded RNA and DNA viruses, bacteria, archae, mitochondria, and eukaryota . We quantify symmetry at orders 1 to 9 for contiguous sequences and pools of coding and non-coding upstream regions, compare the observed symmetry levels to those predicted by simple statistical models, and factor out the effect of lower-order distributions . We establish the universality and variability range of first-order strand symmetry, as well as of its higher-order extensions, and demonstrate the existence of genuine high-order symmetric constraints . We show that ubiquitous reverse-complement symmetry does not result from a single cause, such as point mutation or recombination, but rather emerges from the combined effects of a wide spectrum of mechanisms operating at multiple orders and length scales.

Neurochem Int, 2002 Nov, 41(5), 327 - 32
Neurobiology through the looking-glass: D-serine as a new glial-derived transmitter; Wolosker H et al.; D-Amino acids have been known to be present in bacteria for more than 50 years, but only recently they were identified in mammals . The occurrence of D-amino acids in mammals challenge classic concepts in biology in which only L-amino acids would be present or thought to play important roles . Recent discoveries uncovered a role of endogenous D-serine as a putative glial-derived transmitter that regulates glutamatergic neurotransmission in mammalian brain . Free D-serine levels in the brain are about one third of L-serine values and its extracellular concentration is higher than many common L-amino acids . D-Serine occurs in protoplasmic astrocytes, a class of glial cells that ensheath the synapses and modulate neuronal activity . Biochemical and electrophysiological studies suggest that endogenous D-serine is a physiological modulator at the co-agonist site of NMDA-type of glutamate receptors . We previously showed that D-serine is synthesized by a glial serine racemase, a novel enzyme converting L- to D-serine in mammalian brain . The enzyme requires pyridoxal 5'-phosphate and it was the first racemase to be cloned from eucaryotes . Inhibitors of serine racemase have therapeutic implications for pathological processes in which over-stimulation of NMDA receptors takes place, such as stroke and neurodegenerative diseases . Here, we review the role of endogenous D-serine in modulating NMDA neurotransmission, its biosynthetic apparatus and the potential usefulness of serine racemase inhibitors as a novel neuroprotective strategy to decrease glutamate/NMDA excitotoxicity.

Biochem Biophys Res Commun, 2002 Aug 23, 296(3), 737 - 41
SoxV, an orthologue of the CcdA disulfide transporter, is involved in thiosulfate oxidation in Rhodovulum sulfidophilum and reduces the periplasmic thioredoxin SoxW; Appia-Ayme C et al.; Proteins of the CcdA/DsbD family have previously been found to be involved in the protein disulfide isomerase and cytochrome c maturation pathways of bacteria . SoxV is a CcdA homologue encoded by a genetic locus involved in lithotrophic thiosulfate oxidation in Rhodovulum sulfidophilum . Mutagenesis studies demonstrate an essential and specific role for SoxV in thiosulfate oxidation . Another protein encoded by the same locus, SoxW, is a periplasmic thioredoxin . SoxW was found to be in the reduced state during growth of R . sulfidophilum in the presence of thiosulfate . Maintenance of SoxW in the reduced state was shown to require SoxV . Nevertheless, SoxW was found to be dispensible for thiosulfate oxidation suggesting that SoxV reduces more than one periplasmic partner protein.

Med J Aust, 2002 Aug 19, 177(4), 212 - 9
9: Infections in the returned traveller; Looke DF et al.; The usual presentation of a returned traveller is with a particular syndrome - fever, respiratory infection, diarrhoea, eosinophilia, or skin or soft tissue infection - or for screening for asymptomatic infection . Fever in a returned traveller requires prompt investigation to prevent deaths from malaria; diagnosis of malaria may require up to three blood films over 36-48 hours . Diarrhoea is the most common health problem in travellers and is caused predominantly by bacteria; persistent diarrhoea is less likely to have an infectious cause, but its prognosis is usually good . While most travel-related infections present within six months of return, some important chronic infections may present months or years later (eg, strongyloidiasis, schistosomiasis) . Travellers who have been bitten by an animal require evaluation for rabies prophylaxis.

Clin Exp Rheumatol, 2002 Jul-Aug, 20(4), 455 - 62
The genetically-engineered secretory B27/Q10 chimeric molecule inhibits HLA-B27 restricted alloreactive T-lymphocytes; Kuipers JG et al.; OBJECTIVES: Intracellularly persisting bacterial infections and high association with HLA-B27 are the hallmarks of reactive arthritis . Soluble HLA-B27 molecules are induced by bacterial infection; however their biological role in arthritis is unknown . It was the aim of this study to generate soluble HLA-B27 molecule and to analyze its effect on cytotoxic HLA-B27 alloreactive CD8+ T-lymphocytes in order to better understand potential functional links between persistent infection and HLA-B27 association . METHODS: Using PCR Exons 1 through 4 of HLA-B*2705 were fused to Exon 5 of the soluble murine MHC class I variant Q10 and stably transfected into Hela-cells . Transfectants were analyzed using specific PCR, RT-PCR and intracellular and extracellular staining with anti-HLA-B27 monoclonal antibody ME1 . Secretion of B27Q10 in the supernatant was examined by isoelectric focusing (IEF) . The effect of B27Q10 on T-cells was analyzed using either HLA-B27- or HLA-A2-restricted alloreactive T-cells in a standard 51Cr-release assay . RESULTS: PCR and RT-PCR demonstrated the DNA and mRNA of B27Q10 in the transfectants . By intracellular and extracellular staining with ME1 B27Q10-molecule was detected intracellularly but was not expressed in the cell membrane . Using IEF soluble B27Q10-molecules were found in supernatants of transfectants in a concentration of up to 1.342 microg/ml . Soluble B27QJO-molecule inhibited specifically the cytotoxicity of HLA-B27-restricted alloreactive T-cells by about 30% . CONCLUSION: The secretory non-membrane-expressed molecule B27Q10 inhibits HLA-B27 specific T-cells . The inhibition of cytotoxic T-cells by bacteria induced soluble HLA-B27 may thus enable bacterial persistence.

Berl Munch Tierarztl Wochenschr, 2002 Jul-Aug, 115(7-8), 274 - 7
{Isolation and differentiation of a cytochrome oxidase-negative strain of Ornithobacterium rhinotracheale from turkeys}; Ryll M et al.; The present study describes the first isolation and identification of a cytochrome oxidase-negative strain of Ornithobacterium rhinotracheale . This strain was isolated from 19-week-old turkeys with severe respiratory signs and was identified using biochemical, cytochemical and serological test methods . These findings indicate that cytochrome oxidase-negative Ornithobacterium rhinotracheale strains become probably also an important rule as a causative agent.

Saudi Med J, 2002 Jul, 23(7), 819 - 22
Periductal mastitis . Clinical characteristics and outcome; Ammari FF et al.; OBJECTIVE: To review our experience with periductal mastitis and address the clinical characteristics, management and outcome . METHODS: A retrospective study was carried out at Princess Basma Teaching Hosptal, Irbid, Jordan . Thirty-five patients with the diagnosis of periductal mastitis from the year 1994 through to 2000 were reviewed . Patients presenting with periareolar non-lactating inflammation, a periareolar inflammatory mass, abscess, mammary fistula, or nipple inversion were included in the study . RESULTS: The mean age was 33 years . Pain and pus nipple discharge were the most frequent symptoms . A periareolar mass, induration, mammary duct fistula, or nipple deformity were found in 49%, 43%, 11%, and 34% of the cases . Twenty-six percent were smokers . This ratio increased to 75% among patients with mammary fistulas . Three patients had synchronous skin lesions; the same bacterial strains were isolated from both lesions . This may suggest that breast manipulation, transferring bacteria to the breasts from other parts of the body, might play a role in the etiology . Broad spectrum antibiotics treated all patients . Surgery was necessary for 32 (91%) patients . CONCLUSION: Periductal mastitis is rare and affects non-lactating women during their reproductive life . Etiologically, periductal mastitis is related to bacterial infection and smoking . It mimics other serious breast disorders including carcinoma . On the contrary, duct ectasia affects women between the ages of 42-85 years and is considered an ageing phenomenon which is not related to sepsis or smoking.

Br J Dermatol, 2002 Aug, 147(2), 255 - 60
Atypical exanthems: morphology and laboratory investigations may lead to an aetiological diagnosis in about 70% of cases; Drago F et al.; BACKGROUND: Besides the six classical exanthems, other exanthems may occur, differing in morphology and causative agent (atypical exanthems) . Their aetiological diagnosis is difficult but crucial for both the patient and community concerning issues such as time off school, immunizations, and risks for pregnant women and immunocompromised patients . OBJECTIVES: To investigate whether morphology, associated symptoms and laboratory results can help to determine the aetiology of atypical exanthems . METHODS: We studied 112 consecutive out-patients attending two university dermatology departments . Peripheral blood mononuclear cells (PBMC) and throat, rectal and vaginal swabs were studied to identify viral and bacterial growth . Nested polymerase chain reaction was performed on PBMC and plasma using specific primers for herpesviruses . Serology for common viruses was investigated . RESULTS: We classified the exanthems into seven morphological patterns: macular erythema (32 patients), papular erythema (eight), maculopapular erythema (42), maculopapular erythema with petechiae (seven), erythema with vesiculation (11), erythema with pustules (five) and urticaria (seven) . On the basis of morphology, in concert with the associated symptoms and laboratory results, we found a causal relationship in 76 patients (68%): 25 cases due to drugs, 32 to viruses, 16 to bacteria and three to parasites . A good correspondence between morphology and aetiology was found . The erythematous-vesicular pattern was exclusive to viral infections and was often accompanied by enanthema . The erythemato-pustular and papular patterns were found only in drug-related cases and in some undiagnosed cases . In contrast, the macular and maculopapular patterns were almost evenly distributed among the various aetiologies, although their colour was duskier in the drug-related exanthems . Severe pruritus was associated with drug-related exanthems . CONCLUSIONS: This is the largest series of consecutive patients with atypical exanthems reported . Their morphology and their association with pruritus or constitutional symptoms proved to be important diagnostic clues.

Laryngorhinootologie, 2002 Jul, 81(7), 528 - 33
{The single cell microgelelectrophoresis technique in ecogenotoxicology}; Harreus UA et al.; BACKGROUND: The development of carcinoma in the upper aerodigestive tract is often associated with exposure to xenobiotics . Therefore, the identification of such tumor initiating substances is relevant . Most genotoxicity test systems require mammalian cells, human lymphocytes or cell cultures to detect genotoxicity caused by carcinogens . The single cell microgelelectrophoresis technique (Comet assay) is presented, being a sensitive method, identifying DNA strand breaks, alkali labile sites and DNA repair in human epithelial cells of the upper aerodigestive tract . It is compared to other common techniques for the identification of genotoxic damage . Future applications and contributions of the method are introduced . GENOTOXICITY TEST SYSTEMS: Using the alkaline microgel electrophoresis assay, freshly isolated single epithelial cells are incubated with xenobiotics causing DNA strand breaks and alkali labile sites . Data are examined using a digital computer analysis . The method is described for the application of epithelial cells of the upper aerodigestive tract and compared to other procedures for the monitoring of genotoxicity . These are the Ames test identifying mutagenicity in bacteria, the sister chromatid exchange and the micronucleus test demonstrating genomic instability in lymphocytes and cultured mammalian cells . CONCLUSIONS: The microgel electrophoresis technique is a sensitive method to detect genotoxic effects and DNA repair in human epithelia of the upper aerodigestive tract . The assay offers considerable advantages to other common genotoxicity tests . However, combining of the Comet assay with mini organ cultures allows to use repetitive incubations with xenobiotics . Furthermore, signalling selected chromosomal material by the combination of the assay with the fluorescence in situ hybridisation, DNA-damage and -repair mechanisms within comets can be identified.

Nat Neurosci, 2002 Sep, 5(9), 861 - 7
Pre-existing pathways promote precise projection patterns; Nguyen QT et al.; A large body of evidence shows that molecular cues promote specific synapse formation by guiding axons and by mediating their association with targets, but much less is known about the contribution of physical cues (such as mechanical constraints) to these processes . Here we used the peripheral motor system to investigate the latter issue . In living mice, we viewed individual motor axons bearing a fluorescent reporter, and mapped the cohort of muscle fibers that they innervated both before and after nerve damage . When gross trauma was minimized (by a nerve-crushing rather than nerve-cutting procedure), regenerating axons retraced their former pathways, bifurcated at original branch points, and formed neuromuscular junctions on the same fibers that they originally innervated . Axonal growth through tubes of non-neural cells seemed to account for this specificity, and specificity degraded when the tubes were cut . These results suggest that nonspecific guidance cues can be sufficient to generate specific synaptic circuitry.

Gut, 2002 Sep, 51(3), 398 - 404
Overexpression of alpha(1)-acid glycoprotein in transgenic mice leads to sensitisation to acute colitis; Hochepied T et al.; BACKGROUND: alpha(1)-Acid glycoprotein (alpha(1)-AGP) is an acute phase protein in most mammalian species whose concentration rises 2-5-fold during an acute phase reaction . Its serum concentration has often been used as a marker of disease, including inflammatory bowel disease (IBD) . High alpha(1)-AGP levels were found to have a prognostic value for an increased risk of relapse in IBD . AIMS: To investigate a possible role for increased serum levels of alpha(1)-AGP in the development of IBD . METHODS: Dextran sodium sulphate (DSS) 2% was added to the drinking water of transgenic mice, overexpressing the rat alpha(1)-AGP gene, to induce acute colitis, thus mimicking the conditions of relapse . Clinical parameters, inflammatory parameters, and histological analyses on colon sections were performed . RESULTS: Homozygous alpha(1)-AGP-transgenic mice started losing weight and showed rectal bleeding significantly earlier than heterozygous transgenic or wild-type mice . Survival time of homozygous transgenic mice was significantly shorter compared with heterozygous and wild-type mice . The higher susceptibility of homozygous alpha(1)-AGP-transgenic mice to DSS induced acute colitis was also reflected in higher local myeloperoxidase levels, higher inflammation scores of the colon, and higher systemic levels of interleukin 6 and serum amyloid P component . Local inflammatory parameters were also significantly different in heterozygous transgenic mice compared with wild-type mice, indicating a local dosage effect . In homozygous transgenic mice, significantly higher amounts of bacteria were found in organs but IgA levels were only slightly lower than those of control mice . CONCLUSION: Sufficiently high serum levels of alpha(1)-AGP result in a more aggressive development of acute colitis.

Philos Trans R Soc Lond B Biol Sci, 2002 Jul 29, 357(1423), 937 - 43
Physiological and ecological significance of biological ice nucleators; Lundheim R; When a pure water sample is cooled it can remain in the liquid state at temperatures well below its melting point (0 degrees C) . The initiation of the transition from the liquid state to ice is called nucleation . Substances that facilitate this transition so that it takes place at a relatively high sub-zero temperature are called ice nucleators . Many living organisms produce ice nucleators . In some cases, plausible reasons for their production have been suggested . In bacteria, they could induce frost damage to their hosts, giving the bacteria access to nutrients . In freeze-tolerant animals, it has been suggested that ice nucleators help to control the ice formation so that it is tolerable to the animal . Such ice nucleators can be called adaptive ice nucleators . There are, however, also examples of ice nucleators in living organisms where the adaptive value is difficult to understand . These ice nucleators might be structures with functions other than facilitating ice formation . These structures might be called incidental ice nucleators.

BMC Genomics . 2002 Aug 09;3(1):23.
Pervasive properties of the genomic signature; Jernigan RW et al.; BACKGROUND: The dinucleotide relative abundance profile can be regarded as a genomic signature because, despite diversity between species, it varies little between 50 kilobase or longer windows on a given genome . Both the causes and the functional significance of this phenomenon could be illuminated by determining if it persists on smaller scales . The profile is computed from the base step "odds ratios" that compare dinucleotide frequencies to those expected under the assumption of stochastic equilibrium (thorough shuffling) . Analysis is carried out on 22 sequences, representing 19 species and comprised of about 53 million bases all together, to assess stability of the signature in windows ranging in size from 50 kilobases down to 125 bases . RESULTS: Dinucleotide relative abundance distance from the global signature is computed locally for all non-overlapping windows on each sequence . These distances are log-normally distributed with nearly constant variance and with means that tend to zero slower than reciprocal square root of window size . The mean distance within genomes is larger for protist, plant, and human chromosomes, and smaller for archaea, bacteria, and yeast, for any window size . CONCLUSIONS: The imprint of the global signature is locally pervasive on all scales considered in the sequences (either genomes or chromosomes) that were scanned.

Curr Med Chem, 2002 Sep, 9(18), 1667 - 75
Crystal structures of acridines complexed with nucleic acids; Adams A; Acridines have been used as chemotherapeutic agents against bacteria, protozoa and fungi, and they now find important use as anticancer drugs . There is a paucity of crystal structures of acridine-DNA complexes above the dinucleotide level, but recent structures of acridinecarboxamide topoisomerase II poisons complexed to hexanucleotides have allowed a molecular rationalization of their structure-activity relationships for cytotoxicity and for their kinetics of DNA binding.

J Allergy Clin Immunol, 2002 Aug, 110(2), 209 - 14
Perivascular capillaries in the lung: an important but neglected vascular bed in immune reactions?
Pabst R, Tschernig T.
In allergic and inflammatory immune reactions of the respiratory tract, leukocytes migrate into the different compartments of the lung . The air space can easily be sampled by means of bronchoalveolar lavage . However, the subset composition in the bronchial wall or the lung interstitium often differs considerably from that of the bronchoalveolar lavage fluid . A further compartment involved in very heterogeneous immune reactions in the lung has thus far not been mentioned: the periarterial space . In numerous experiments in different species with virus, bacteria, fungi, or allergens, there was not only a leukocyte infiltration of the bronchial lamina propria but also infiltration around branches of the pulmonary artery . This thus far neglected compartment consists of a different type of capillary . Thus it is important not to overlook this area in studies on allergic or inflammatory immune reactions of the lung.

Bioinformatics, 2002, 18 Suppl 1, S46 - 53
A sequence-profile-based HMM for predicting and discriminating beta barrel membrane proteins; Martelli PL et al.; MOTIVATION: Membrane proteins are an abundant and functionally relevant subset of proteins that putatively include from about 15 up to 30% of the proteome of organisms fully sequenced . These estimates are mainly computed on the basis of sequence comparison and membrane protein prediction . It is therefore urgent to develop methods capable of selecting membrane proteins especially in the case of outer membrane proteins, barely taken into consideration when proteome wide analysis is performed . This will also help protein annotation when no homologous sequence is found in the database . Outer membrane proteins solved so far at atomic resolution interact with the external membrane of bacteria with a characteristic beta barrel structure comprising different even numbers of beta strands (beta barrel membrane proteins) . In this they differ from the membrane proteins of the cytoplasmic membrane endowed with alpha helix bundles (all alpha membrane proteins) and need specialised predictors . RESULTS: We develop a HMM model, which can predict the topology of beta barrel membrane proteins using, as input, evolutionary information . The model is cyclic with 6 types of states: two for the beta strand transmembrane core, one for the beta strand cap on either side of the membrane, one for the inner loop, one for the outer loop and one for the globular domain state in the middle of each loop . The development of a specific input for HMM based on multiple sequence alignment is novel . The accuracy per residue of the model is 83% when a jack knife procedure is adopted . With a model optimisation method using a dynamic programming algorithm seven topological models out of the twelve proteins included in the testing set are also correctly predicted . When used as a discriminator, the model is rather selective . At a fixed probability value, it retains 84% of a non-redundant set comprising 145 sequences of well-annotated outer membrane proteins . Concomitantly, it correctly rejects 90% of a set of globular proteins including about 1200 chains with low sequence identity (<30%) and 90% of a set of all alpha membrane proteins, including 188 chains.

Pathol Biol (Paris), 2002 Jul, 50(6), 401 - 12
{Brucella at the dawn of the third milenium: genomic organization and pathogenesis}; Michaux-Charachon S et al.; Bacteria of the genus Brucella, responsible for brucellosis, are pathogenic for animals and occasionally for humans . The cost of this widespread zoonotic infection is still very high for the community . Over the last few years, there have been advances in two main domains . First, the Brucella genome has been shown to be complex, with two circular chromosomes . Second, recent data on the virulence of Brucella suggest common mechanisms shared with plant pathogens and endosymbionts of the alpha-proteobacteria . Understanding virulence will have practical repercussions in the realms of vaccine development and, perhaps, development of new antibiotics . Two complete Brucella genome sequences are now available and will be a gold mine of information to guide future research.

J Contemp Dent Pract, 2001 Nov 15, 2(4), 1 - 17
Fundamentals of breath malodour; Sanz M et al.; Breath malodour is a condition that has health and social implications . The origin of breath malodour problems are related to both systemic and oral conditions . The advice of dental professionals for treatment of this condition occurs with regularity since 90% of breath odor problems emanate from the oral cavity . This paper provides a comprehensive review of the etiology of breath odor, its prevalence, diagnosis, and treatment strategies for the condition.

J Contemp Dent Pract, 1999 Nov 15, 1(1), 1 - 8
The concept of "risk" and the emerging discipline of periodontal medicine; Paquette DW et al.; Dental clinicians intuitively weigh patient risks for developing disease and use that information for making treatment decisions and recommendations . Periodontitis, for instance, is one oral disease with documented risk factors including smoking, specific plaque bacteria and diabetes mellitus . While this link between systemic disease and periodontitis was thought to be unidirectional, mounting evidence in the last decade suggests that the relationship may be bi-directional . Cross sectional and case control studies indicate that periodontitis may confer two and seven-fold elevations in risk for cardiovascular disease and premature low birth weight respectively . While these early studies indicate potential associations between oral and systemic health, they support the central hypothesis that periodontitis triggers both local and systemic host inflammatory responses . Consequently, a new discipline, periodontal medicine, has emerged in dentistry which seeks to further define these interrelationships through scientific inquiry . Ultimately, this new knowledge may prove useful in intervention strategies to reduce patient risks and prevent systemic disease outcomes . This manuscript clarifies the concept of risk, traces the emergence of periodontal medicine and serves as a resource for the oral health professional in assessing and utilizing the current evidence on periodontal-systemic disease connections.

Biologist (London), 2002 Aug, 49(4), 145 - 9
Give us this day our daily germs; Rook GA et al.; Are we sparing the dirt and spoiling our children's immune systems? The theory that some germs are necessary in developing healthy immune systems is gaining credence as more evidence emerges . It is vital that we find out which germs are needed, when and how, before the increase in diseases attributable to faulty regulation of the immune system (allergies, autoimmunity, inflammatory bowel disease) spirals out of control.

Genes Cells, 2002 Aug, 7(8), 769 - 80
The VAR1 locus of Arabidopsis encodes a chloroplastic FtsH and is responsible for leaf variegation in the mutant alleles; Sakamoto W et al.; BACKGROUND: A leaf-variegated mutation var1 of Arabidopsis results in the development of abnormal plastids and the formation of a green/white sector . Genetic analysis of the var1 mutant indicated that it acts synergistically with another mutation var2, suggesting that the two genes are relevant . The VAR2 locus has been shown to encode a chloroplastic FtsH, an ATP-dependent protease which is possibly involved in the degradation of thylakoid proteins and plastid development . RESULTS: In this study we show that the VAR1 locus encodes a chloroplastic FtsH protein homologous to VAR2 . VAR1 contains a conserved motif for ATPase and a metalloprotease characteristic to FtsH proteins, and is targeted into chloroplasts . A VAR1-fusion protein synthesized in vitro exhibited ATPase activity and partial metalloprotease activity . The maximum yield of photochemistry, measured by chlorophyll fluorescence, showed that the var1 mutants were sensitive to photoinhibitory light exposure at 800 micro mol/m2/s . CONCLUSION: VAR1 and VAR2 comprise an FtsH small gene family together with other FtsH genes in Arabidopsis . VAR1 as well as VAR2 may play an important role in degrading photodamaged subunits in photosystem II . Loss of VAR1 and VAR2 perhaps impairs the photoprotection mechanism and thylakoid development, causing leaf variegation as a consequence.

J Agric Food Chem, 2002 Aug 14, 50(17), 4916 - 8
Biotransformation of alpha-terpineol by the larvae of common cutworm (Spodoptera litura); Miyazawa M et al.; Biotransformation of alpha-terpineol by the common cutworm (Spodoptera litura) larvae was investigated . alpha-Terpineol was mixed in an artificial diet, and the diet was fed to the larvae (fourth-fifth instar) of S . litura . Metabolites were isolated from the frass and analyzed spectroscopically . Main metabolites were 7-hydroxy-alpha-terpineol (p-menth-1-ene-7,8-diol) and oleuropeic acid (8-hydroxy-p-menth-1-en-7-oic acid) . Intestinal bacteria from the frass of larvae did not participate in the metabolism of alpha-terpineol . alpha-Terpineol was preferentially oxidized at the C-7 position (allylic methyl group) by S . litura larvae.

J Int Med Res, 2002 May-Jun, 30(3), 325 - 9
Use of OM-85 BV for the prevention of acute respiratory tract infections in occupational medicine; Carmona-Ramirez MA et al.; This study evaluated the safety and efficacy of the immunostimulatory agent OM-85 BV in 112 male car-factory workers who were highly susceptible to acute respiratory tract infections (ARTIs), each having experienced > or = 4 ARTIs during 1999 . From January to March 2000, each worker received one capsule of OM-85 BV (7 mg) per day for 10 consecutive days each month . The patients were followed for a further 9 months . Mean number of ARTIs decreased from 8.2 +/- 2.1 per worker in 1999 to 5.3 +/- 2.9 in 2000; i.e . a difference of -2.9 (95% confidence intervals, -3.5 to -2.4) . Similar effects were observed in men who had different job roles, and no adverse events were reported during drug administration . We concluded that OM-85 BV appears to be safe and effective in reducing the incidence of ARTIs in susceptible workers, although further double-blind, placebo-controlled clinical trials are required.

Oncogene, 2002 Aug 15, 21(36), 5574 - 81
Evidence for dysregulation of cell cycle by human polyomavirus, JCV, late auxiliary protein; Darbinyan A et al.; The late region of the human neurotropic JC virus encodes a 71 amino acid protein, named Agnoprotein, whose biological function remains elusive . Here we demonstrate that in the absence of other viral proteins, expression of Agnoprotein can inhibit cell growth by deregulating cell progression through the cell cycle stages . Cells with constitutive expression of Agnoprotein were largely accumulated at the G2/M stage and that decline in the activity of cyclins A and B is observed in these cells . Agnoprotein showed the ability to augment p21 promoter activity in transient transfection assay and a noticeable increase in the level of p21 is detected in cells continuously expressing Agnoprotein . Results from binding studies revealed the interaction of Agnoprotein with p53 through the N-terminal of the Agnoprotein spanning residues 1-36 . Co-expression of p53 and Agnoprotein further stimulated transcription of the p21 promoter . Thus, the interaction of p53 and Agnoprotein can lead to a higher level of p21 expression and suppression of cell cycle progression during the cell cycle.

J Mol Evol, 2002 Jul, 55(1), 85 - 91
Rates of ribosomal RNA evolution are uniquely accelerated in eukaryotes; Syvanen M; A novel procedure for testing the relative rates of evolution is described . The procedure, the distance-matrix rate test, consists of creating a graph that displays two complete distance matrices for two different genes derived from the same group of species, an approach made practical by numerous whole genomic sequences . The results in this paper show that the molecular clock of ribosomal RNA from Eukaryotes is uniquely accelerated and highly variable while those of Archaea and Bacteria are not . This idiosyncratic eukaryotic rRNA evolution is not observed with four different protein genes . The distance matrix rate test consists of plotting the distance of one gene (from two different species) against the distance of a second gene (from the same pair of species) in the form of a simple X-Y plot . Because it is not possible to compute variances (or co-variances in this case) that can be meaningfully compared to expectations from a Poisson process, the test does not permit calculations of an index of dispersion . In place of this, equations are given for the 95% confidence limits expected for a Poisson process . The test was applied to the proteins rpsl1 and rp114, as one example, and to rps11 and ssu rRNA as a second example . In addition, the cytochrome c and cytochrome c oxidase evolution from a larger group of Eukaryotes are compared to each other and that of the ssu rRNA . This graphical test shows that the evolution of the four proteins and the archael and bacterial ssu rRNA's are consistent with a Poisson process since last common ancestor . The distance-matrix rate test that is introduced in this study needs to make no assumptions regarding evolutionary rates, divergence times, or phylogenetic relationships.

Med Sci Monit, 2002 Aug, 8(8), BR283 - 8
Recognition of substrate and Skp1 by the Homologue of Slimb (HOS) ubiquitin ligase receptor D role of the F-box; Herter JR et al.; BACKGROUND: SCFHOS-Roc1 E3 ubiquitin ligase is an enzymatic complex, which mediates ubiquitination and subsequent proteasome-dependent degradation of phosphorylated inhibitor of NF-kB (IkB) and b-catenin . HOS is a WD40 repeats/F-box-containing protein that actually associates with the substrates and binds to Skp1 via the F-box . MATERIAL/METHODS: Here, we have studied the structural determinants of the substrate recognition and ligase recruitment by HOS . The binding (pull-down and immunoprecipitation assays) and ubiquitination assays were performed in vitro with purified or partially purified recombinant proteins obtained via expression in bacteria or mammalian cells or by in vitro translation . RESULTS: We identified specific amino acid residues (I143 and L152) within the F-box of HOS that play a critical role in maintaining the hydrophobic interface of HOS-Skp1 interaction and found substantial similarity between interaction of Skp1 with HOS and with another F-box protein Skp2 . Binding of Skp1 augments the ability of HOS to recognize the phosphorylated IkBa . CONCLUSIONS: These observations indicate the role of the F-box of HOS in both recruitment of ubiquitin ligase activity and substrate recognition as well as identify the structural elements that are important for both functions of HOS F-box domain.

Thromb Res, 2002 Apr 1, 106(1), 71 - 9
Differences between human and rabbit coagulation factor X-implications for in vivo models of thrombosis; Edwards ST et al.; The activation of factor X (fX) to factor Xa (fXa) marks the penultimate step in the coagulation cascade and modulating fXa activity may be effective for antithrombotic therapy . Even though fXa inhibitors are screened using in vitro inhibition of human fXa (HfXa) while subsequent evaluation uses in vivo rabbit models, there is limited knowledge of species differences between the coagulation proteins . When comparing amino acid sequences for the human (HfX) and rabbit (RafX) protein, differences are found in the activation peptide and active site regions . In order to study the relative functional characteristics of HfX and RafX, we asked (1) whether fX from the two species is immunologically related, (2) whether the two proteins are activated to fXa in a similar manner, (3) whether HfXa and rabbit factor Xa (RafXa) have similar catalytic activities toward tripeptide substrates . To answer (1), we expressed RafX-glutathione S-transferase (RafX-GST) fusion protein in bacteria and purified the protein for use as an antigen . The resulting monoclonal antibodies were suitable for affinity purification of plasma RafX and for effective anticoagulation in rabbit plasma clotting assays . We found two antibodies (mAb 214 and mAb 290) that anticoagulated rabbit plasma in a dose responsive manner but did not cross-react with human plasma . At a concentration of 500 nM, mAb 214 attained a two-fold extension of rabbit plasma activated partial thromboplastin time (aPTT) . To answer (2), we purified plasma RafX and compared the activation of HfX and RafX with Russell's viper venom (RVV-X) . Under equivalent reaction conditions, conversion was 30% slower for the rabbit protein . To answer (3), amidolytic activity of HfXa and RafXa were assayed by cleavage of three para-nitroanilide (pNA) substrates (S2222 {Bz-Ile-Glu(gamma-OR)-Gly-Arg-pNA.HCl}, S2765 {Z-D-Arg-Gly-Arg-pNA.HCl} and Spectrozyme Xa {MeO-CO-D-CHG-Gly-Arg-pNA.AcOH}) . Michaelis constants (K(m)) for the rabbit protein were 187, 72 and 69 microM, respectively, and for the human analog, 255, 63 and 135 microM, respectively . Comparing the extent of substrate turnover (V(max)) for HfXa and RafXa, the latter was shown to cleave all three substrates at a reduced rate . Based on these observations, it can be speculated that the relative antithrombotic potency of active site directed fXa inhibitors might be different between the two species . Predicted human therapeutic doses derived from in vivo results in rabbit models should therefore take species variation into consideration.

Tissue Cell, 2002 Apr, 34(2), 98 - 102
Activated host neutrophils in the larval midgut lumen of the human bot fly Dermatobia hominis; Leite AC et al.; Light microscopy (LM) and transmission electron microscopy (TEM) were used to observe activated polymorphonuclear neutrophils from mammalian hosts as well as invading bacteria in the midgut lumen of larvae of the human bot fly Dermatobia hominis . Other resident or recruited cells associated with dermal myiasis were fed on by larvae and digested more rapidly than neutrophils . The latter were observed moving towards bacteria and particles of food, extending the filopodia and engulfing material to be digested within phagosomes . The larval midgut lumen, thus, appears to be a suitable environment to produce neutrophil activation at least for short periods, as seen in mammalian hosts . Although interactions between phagocytes and bacteria in the midgut lumen may be important in bot fly larval development, further studies are required to confirm this.

Parasite Immunol, 2002 Jul, 24(7), 363 - 7
Cellular responses to Schistosoma japonicum cathepsin D aspartic protease; Verity CK et al.; Lymphocyte proliferation and cytokine production were measured in groups of mice vaccinated (but not subsequently challenge infected) with recombinant forms of Schistosoma japonicum cathepsin D aspartic protease, rSjASP1 (expressed in bacteria; enzymatically inactive) and rSjASP2 (expressed in insect cells; enzymatically active) . Both forms of the schistosome enzyme induced significant proliferation of splenocytes recovered from vaccinated mice, and expression of interferon (IFN)-gamma, interleukin (IL)-4 and IL-10 mRNA in these cells was detected using reverse transcriptase-polymerase chain reaction . Secretion of IFN-gamma, IL-4 and IL-10 by splenocytes from vaccinated mice was confirmed and quantified using enzyme-linked immunosorbent assay . IFN-gamma was the most abundant cytokine produced, followed by IL-4 and IL-10 in rank order . These findings indicated that vaccination of mice with the schistosome protease induces a mixed Th1/Th2 cytokine response, which may explain the modest level of protection after challenge infection in cathepsin D-vaccinated mice, reported previously.

Plant J, 2002 Aug, 31(3), 375 - 83
pGD vectors: versatile tools for the expression of green and red fluorescent protein fusions in agroinfiltrated plant leaves; Goodin MM et al.; We have constructed a matched set of binary vectors designated pGD, pGDG and pGDR for the expression and co-localization of native proteins and GFP or DsRed fusions in large numbers of plant cells . The utility of these vectors following agroinfiltration into leaves has been demonstrated with four genes from Sonchus yellow net virus, a plant nucleorhabdovirus, and with a nucleolar marker protein . Of the three SYNV proteins tested, sc4 gave identical localization patterns at the cell wall and nucleus when fused to GFP or DsRed . However, some differences in expression patterns were observed depending on whether DsRed or GFP was the fusion partner . In this regard, the DsRed:P fusion showed a similar pattern of localization to GFP:P, but localized foci appeared in the nucleus and near the periphery of the nucleus . Nevertheless, the viral nucleocapsid protein, expressed as a GFP:N fusion, co-localized with DsRed:P in a subnuclear locale in agreement with our previous observations (Goodin et al., 2001) . This locale appears to be distinct from the nucleolus as indicated by co-expression of the N protein, DsRed:P and a nucleolar marker AtFib1 fused to GFP . The SYNV M protein, which is believed to be particularly prone to oligomerization, was detectable only as a GFP fusion . Our results indicate that agroinfiltration with bacteria containing the pGD vectors is extremely useful for transient expression of several proteins in a high proportion of the cells of Nicotiana benthamiana leaves . The GFP and DsRed elements incorporated into the pGD system should greatly increase the ease of visualizing co-localization and interactions of proteins in a variety of experimental dicotyledonous hosts.

J Virol, 2002 Sep, 76(17), 8560 - 71
mRNA degradation by the virion host shutoff (Vhs) protein of herpes simplex virus: genetic and biochemical evidence that Vhs is a nuclease; Everly DN Jr et al.; During lytic infections, the virion host shutoff (Vhs) protein (UL41) of herpes simplex virus destabilizes both host and viral mRNAs . By accelerating the decay of all mRNAs, it helps redirect the cell from host to viral gene expression and facilitates the sequential expression of different classes of viral genes . While it is clear that Vhs induces mRNA degradation, it is uncertain whether it is itself an RNase or somehow activates a cellular enzyme . This question was addressed by using a combination of genetic and biochemical approaches . The Vhs homologues of alphaherpesviruses share sequence similarities with a family of mammalian, yeast, bacterial, and phage nucleases . To test the functional significance of these similarities, Vhs was mutated to alter residues corresponding to amino acids known to be critical to the nuclease activity of cellular homologues . In every instance, mutations that inactivated the nuclease activity of cellular homologues also abolished Vhs activity . Recent experiments showed that Vhs interacts with the cellular translation initiation factor eIF4H . In this study, the coexpression of Vhs and a glutathione S-transferase (GST)-eIF4H fusion protein in bacteria resulted in the formation of a complex of the proteins . The wild-type Vhs/GST-eIF4H complex was isolated and shown to have RNase activity . In contrast, Vhs mutations that altered key residues in the nuclease motif abolished the nuclease activity of the recombinant Vhs/GST-eIF4H complex . The results provide genetic and biochemical evidence that Vhs is an RNase, either alone or as a complex with eIF4H.

J Biol Chem, 2002 Oct 11, 277(41), 38441 - 8 Epub 2002 Aug 05.
A nickel-cobalt-sensing ArsR-SmtB family repressor . Contributions of cytosol and effector binding sites to metal selectivity; Cavet JS et al.; NmtR from Mycobacterium tuberculosis is a new member of the ArsR-SmtB family of metal sensor transcriptional repressors . NmtR binds to the operator-promoter of a gene encoding a P(1) type ATPase (NmtA), repressing transcription in vivo except in medium supplemented with nickel or, to some extent, cobalt . In a cyanobacterial host, Synechococcus PCC 7942 strain R2-PIM8(smt), NmtR-mediated repression is alleviated by cobalt but not nickel or zinc addition, while the related sensor SmtB responds exclusively to zinc . Quantification of the number of atoms of nickel per cell shows that NmtR nickel sensitivity correlates with cytosolic nickel contents . Differential metal discrimination in a common cytosol by SmtB (zinc) and NmtR (cobalt) is not simply explained by affinities at equilibrium; although NmtR does bind nickel substantially more tightly than SmtB, it has a higher affinity for zinc than for cobalt and binds cobalt more weakly than SmtB . SmtB is known to bind and sense zinc at interhelical four-coordinate, tetrahedral sites across the C-terminal alpha 5 helices, while absorption spectroscopy of Co(II)- and Ni(II)-substituted NmtR reveals five- and six-coordinate metal complexes . Site-directed mutagenesis identifies six potential cobalt/nickel ligands that are obligatory for inducer recognition but not repression by NmtR, four of which (Asp(91), His(93), His(104), His(107)) align with alpha 5 ligands of SmtB with two additional His provided by a carboxyl-terminal "extension" (designated alpha 5C) . Gel retardation assays reveal that zinc does not allosterically regulate NmtR-DNA binding at concentrations where lower affinity cobalt does . These data suggest that two additional ligands form hexacoordinate metal complexes and are crucial for driving allosteric regulation of DNA binding by NmtR, thereby allowing NmtR to preferentially sense metals that favor higher coordination numbers relative to SmtB.

J Cell Biol, 2002 Aug 5, 158(3), 435 - 44 Epub 2002 Aug 05.
Cell cycle- and swelling-induced activation of a Caenorhabditis elegans ClC channel is mediated by CeGLC-7alpha/beta phosphatases; Rutledge E et al.; ClC voltage-gated anion channels have been identified in bacteria, yeast, plants, and animals . The biophysical and structural properties of ClCs have been studied extensively, but relatively little is known about their precise physiological functions . Furthermore, virtually nothing is known about the signaling pathways and molecular mechanisms that regulate channel activity . The nematode Caenorhabditis elegans provides significant experimental advantages for characterizing ion channel function and regulation . We have shown previously that the ClC Cl- channel homologue CLH-3 is expressed in C . elegans oocytes, and that it is activated during meiotic maturation and by cell swelling . We demonstrate here that depletion of intracellular ATP or removal of Mg2+, experimental maneuvers that inhibit kinase function, constitutively activate CLH-3 . Maturation- and swelling-induced channel activation are inhibited by type 1 serine/threonine phosphatase inhibitors . RNA interference studies demonstrated that the type 1 protein phosphatases CeGLC-7alpha and beta, both of which play essential regulatory roles in mitotic and meiotic cell cycle events, mediate CLH-3 activation . We have suggested previously that CLH-3 and mammalian ClC-2 are orthologues that play important roles in heterologous cell-cell interactions, intercellular communication, and regulation of cell cycle-dependent physiological processes . Consistent with this hypothesis, we show that heterologously expressed rat ClC-2 is also activated by serine/threonine dephosphorylation, suggesting that the two channels have common regulatory mechanisms.

FEBS Lett, 2002 Aug 14, 525(1-3), 156 - 63
Coupled rotation within single F0F1 enzyme complexes during ATP synthesis or hydrolysis; Kaim G et al.; F0F1 ATP synthases are the smallest rotary motors in nature and work as ATP factories in bacteria, plants and animals . Here we report on the first observation of intersubunit rotation in fully coupled single F0F1 molecules during ATP synthesis or hydrolysis . We investigate the Na+-translocating ATP synthase of Propionigenium modestum specifically labeled by a single fluorophore at one c subunit using polarization-resolved confocal microscopy . Rotation during ATP synthesis was observed with the immobilized enzyme reconstituted into proteoliposomes after applying a diffusion potential, but not with a Na+ concentration gradient alone . During ATP hydrolysis, stepwise rotation of the labeled c subunit was found in the presence of 2 mM NaCl, but not without the addition of Na+ ions . Moreover, upon the incubation with the F0-specific inhibitor dicyclohexylcarbodiimide the rotation was severely inhibited.

Pharmacol Ther, 2002 Jul, 95(1), 89 - 100
LOX-1, the receptor for oxidized low-density lipoprotein identified from endothelial cells: implications in endothelial dysfunction and atherosclerosis; Chen M et al.; Lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (LOX-1) was initially identified as the major receptor for oxidized LDL (OxLDL) in endothelial cells . Its inducible expression in macrophages and smooth muscle cell was also observed . LOX-1 is a Type II membrane protein with a typical C-type lectin structure at the extracellular C-terminus . It can be cleaved by an unknown protease at the extracellular juxtamembrane region to release the soluble form of LOX-1 . The extracellular domains of LOX-1 are post-translationally modified by N-linked glycosylation . Mutagenesis studies revealed that the lectin domain of LOX-1 is the functional domain that recognizes the LOX-1 ligand . The C-terminal end residues and several conserved positively charged residues spanning the lectin domain are essential for OxLDL binding . LOX-1 activation by OxLDL causes endothelial changes that are characterized by activation of nuclear factor-kappaB through an increased reactive oxygen species, subsequent induction of adhesion molecules, and endothelial apoptosis . In vitro, expression of LOX-1 is induced by many inflammatory cytokines, oxidative stress, hemodynamic stimuli, and OxLDL . In vivo, the expression is enhanced in pro-atherogenic settings including, hypertension, hyperlipidemia, and diabetes, and, indeed, is accumulated in the atherosclerotic and glomerulosclerotic lesions . LOX-1 binds multiple classes of ligands that are implicated in the pathogenesis of atherosclerosis . Besides OxLDL, LOX-1 can recognize apoptotic/aged cells, activated platelets, and bacteria, implying versatile physiological functions . Taken together, all these findings support the possible contribution of LOX-1 to the pathogenesis of vascular disorders, particularly atherosclerosis . Development of antagonists for LOX-1 might be a good therapeutic approach to vascular diseases.

Curr Opin Struct Biol, 2002 Aug, 12(4), 531 - 9
CLC chloride channels: correlating structure with function; Estevez R et al.; CLC chloride channels form a large gene family that is found in bacteria, archae and eukaryotes . Previous mutagenesis studies on CLC chloride channels, combined with electrophysiology, strongly supported the theory that these channels form a homodimeric structure with one pore per subunit (a'double-barrelled' channel), and also provided clues about gating and permeation . Recently, the crystal structures of two bacterial CLC proteins have been obtained by X-ray diffraction analysis . They confirm the double-barrelled architecture, and reveal a surprisingly complex and unprecedented channel structure . At its binding site in the pore, chloride interacts with the ends of four helices that come from both sides of the membrane . A glutamate residue that protrudes into the pore is proposed to participate in gating . The structure confirms several previous conclusions from mutagenesis studies and provides an excellent framework for their interpretation.

J Mol Biol, 2002 Aug 16, 321(3), 447 - 57
Insights into signal transduction revealed by the low resolution structure of the FixJ response regulator; Birck C et al.; Two-component regulatory systems mediate most of the bacterial cells responses to a variety of signals . In Sinorhizobium meliloti, the FixL-FixJ couple controls the expression of the nitrogen fixation genes through the binding of the two-domains response regulator FixJ to the fixK and nifA promoters . Phosphorylation of the N-terminal regulatory domain activates the protein and releases the inhibition of the C-terminal DNA-binding domain that occurs in the unphosphorylated protein . Insights into the transition from the inactive to the active form are provided by the architecture of the unphosphorylated response regulator reported in this study . The relative position and orientation of the N and C-terminal domains were defined from the molecular envelope restored from small-angle X-ray scattering (SAXS) data . The involvement of the alpha4-beta5-alpha5 surface of the regulatory domain, the linker region and the C-terminal helix of the DNA-binding domain in the interdomain interface of unphosphorylated FixJ was supported by biochemical investigations . These results, together with the previously reported studies on the phosphorylated regulatory domain of FixJ, emphasize the role of the alpha4-beta5-alpha5 surface in mediating a flow of information in this response regulator . This first study by SAXS of proteins from two-component systems suggests that the method could be successfully applied to other members of this family and could be suitable for the study of multidomain proteins and protein-protein complexes regulated through molecular interfaces in the low micromolar range.

J Interferon Cytokine Res, 2002 Jun, 22(6), 617 - 20
Reduced cytokine secretions by LAK cells of pulmonary tuberculosis patients in response to tumor targets in vitro; Nirmala R et al.; Activation of macrophages and other immune components to release a series of proinflammatory cytokines is one of the first events in innate resistance to intracellular infections . Severe manifestations of tuberculosis (TB) could be caused by alterations in the balance of these cytokines . In this study, lymphokine-activated killer (LAK) cells of TB patients and normal individuals were generated by stimulation with cytokines in vitro . The LAK cells of both groups were further triggered with allogeneic tumor targets . Cytokines interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and granulocyte-macrophage colony-stimulating factor (GM-CSF) were estimated in the supernatants generated in the two groups . The aim was to see if infection with TB influenced the secretory capacity of the immune cells in vitro . Reduced cytokine profiles were observed in TB patients, indicating defective interactions between patient effector cells with allogeneic transformed cells compared with normal individuals . Partial restoration of IFN-gamma production was seen with a combination of cytokines interleukin-2 (IL-2) and IL-12 in TB patients . Based on the in vitro observations, we hypothesize that in vivo also there is diminished immune cell activation of effector cells in response to the presence of infected macrophages . This probably leads to a diminished secretory function that can be corrected by the use of such cytokines as IL-2 and IL-12 . The effector populations of TB patients are probably in a state of target-induced anergy, allowing the bacteria to thrive, and immunomodulatory cytokines that improve the host immune response toward countering mycobacterial infection.

J Med Dent Sci, 2000 Mar, 47(1), 55 - 9
Correlation in inorganic ion concentration between saliva and plaque fluid; Tanaka M et al.; The composition and the concentration of inorganic ions in dental plaque significantly influence the initiation and the development of dental caries through altering the degree of saturation of the aqueous phase surrounding the dental enamel . In order to know how plaque is affected by saliva, the composition and the concentration of inorganic ions in saliva and plaque fluid were investigated . The ionic concentrations of sodium and chlorine had similar values between plaque fluid and saliva . However, the concentrations of the inorganic ions such as ammonium, potassium, magnesium, calcium, and phosphate were significantly different between plaque fluid and saliva . This meant that the saliva and plaque fluid were different in its inorganic composition presumably reflected by the metabolic activity of bacteria in the plaque . On the other hand, as for the correlation coefficients between plaque fluid and saliva composition, statistically significant correlation was observed in ions such as sodium, ammonium, potassium, magnesium, and chlorine but not in calcium, phosphate, or in pH values . This was possibly due to the fact that saliva was the main source of supply of these ions . However as for calcium and phosphate, no close correlation was found possibly because they could be supplied also through tooth enamel dissolution . The discrepancy of the results with former studies on this point was speculatively explained by,the difference of the plaque age used . It was considered reasonable that the pH value was independent, as it is mainly decided by the activity of the bacteria in the plaque.

Clin Rev Allergy Immunol, 2002 Aug, 23(1), 5 - 27
The role of inflammation in the pathophysiology of CF lung disease; Chmiel JF et al.; Cystic fibrosis (CF) lung disease is characterized by a self-perpetuating cycle of airway obstruction, chronic bacterial infection, and vigorous inflammation that results in structural damage to the airway . CF patients have a predilection for infection with a limited spectrum of distinctive bacteria that initiate a vigorous inflammatory response which is more harmful than protective . The airway epithelial cell, which normally expresses the cystic fibrosis transmembrane conductance regulator (CFTR), directs the inflammatory response . Defects in CFTR are associated with increased production of pro-inflammatory mediators including IL-8, a potent neutrophil chemoattractant that stimulates the influx of massive numbers of neutrophils into the airways . These neutrophils are the primary effector cells responsible for the pathological manifestations of CF lung disease . Documented deficiencies in immunoregulatory molecules such as IL-10 likely contribute to the generation of the excessive and persistent inflammatory response . Since inflammation is a key contributor to the pathogenesis of CF lung disease, anti-inflammatory therapy must assume a larger role in CF until a cure is discovered . To date, attention has focused primarily on the therapeutic potential of systemic and inhaled corticosteroids and the non-steroidal anti-inflammatory drug (NSAID) ibuprofen . Development of new anti-inflammatory therapies that impact intracellular signaling pathways and cell-cell communication molecules likely will have the greatest impact on limiting the excessive production of the inflammatory mediators in the CF lung, thereby slowing the decline in lung function and improving survival.

J Biol Chem, 2002 Oct 4, 277(40), 37235 - 41 Epub 2002 Aug 02.
High-affinity activators of cystic fibrosis transmembrane conductance regulator (CFTR) chloride conductance identified by high-throughput screening; Ma T et al.; Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR) protein that reduce cAMP-stimulated Cl(-) conductance in airway and other epithelia . The purpose of this investigation was to identify new classes of potent CFTR activators . A collection of 60,000 diverse drug-like compounds was screened at 10 microm together with a low concentration of forskolin (0.5 microm) in Fisher rat thyroid epithelial cells co-expressing human CFTR and a green fluorescent protein-based Cl(-) sensor . Primary screening yielded 57 strong activators (greater activity than reference compound apigenin), most of which were unrelated in chemical structure to known CFTR activators, and 284 weaker activators . Secondary analysis of the strong activators included analysis of CFTR specificity, forskolin requirement, transepithelial short-circuit current, activation kinetics, dose response, toxicity, and activation mechanism . Three compounds, the most potent being a dihydroisoquinoline, activated CFTR by elevating cellular cAMP, probably by phosphodiesterase inhibition . Fourteen compounds activated CFTR without cAMP elevation or phosphatase inhibition, suggesting direct CFTR interaction . The most potent compounds had tetrahydrocarbazol, hydroxycoumarin, and thiazolidine core structures . These compounds induced CFTR Cl(-) currents rapidly (<5 min) with K(d) down to 200 nm and were CFTR-selective, reversible, and nontoxic . Several compounds, the most potent being a trifluoromethylphenylbenzamine, activated the CF-causing mutant G551D, but with much weaker affinity (K(d) > 10 microm) . When added for 10 min, none of the compounds activated DeltaPhe(508)-CFTR in transfected cells grown at 37 degrees C (with DeltaPhe(508)-CFTR trapped in the endoplasmic reticulum) . However, after correction of trafficking by 48 h of growth at 27 degrees C, tetrahydrocarbazol and N-phenyltriazine derivatives strongly stimulated Cl(-) conductance with K(d) < 1 microm . The new activators identified here may be useful in defining molecular mechanisms of CFTR activation and as lead compounds in CF drug development.

Bioorg Med Chem Lett, 2002 Sep 2, 12(17), 2341 - 4
Muraymycins, novel peptidoglycan biosynthesis inhibitors: semisynthesis and SAR of their derivatives; Lin YI et al.; Sixteen muraymycin derivatives 2-17 were synthesized based on selective reactions of the primary and secondary amino groups of muraymycin C1 (1) with isocyanates and aldehydes . Disubstituted derivatives 3-9 demonstrated no activity against either MraY or MurG at <or=100 microg/mL whereas mono substituted derivatives 11-17 demonstrated good inhibitory activity, well correlated with the lipophilicity of the substituent introduced . In particular, the activity of derivatives 13 and 14 was comparable to that of muraymycin C1 in this assay.

Free Radic Biol Med, 2002 Aug 15, 33(4), 457 - 63
Ferritin, iron homeostasis, and oxidative damage; Arosio P et al.; Ferritin is one of the major proteins of iron metabolism . It is almost ubiquitous and tightly regulated by the metal . Biochemical and structural properties of the ferritins are largely conserved from bacteria to man, although the role in the regulation of iron trafficking varies in the different organisms . Recent studies have clarified some of the major aspects of the reaction between iron and ferritin, which results in the formation of the iron core and production of hydrogen peroxide . The characterization of cellular models in which ferritin expression is modulated has shown that the ferroxidase catalytic site on the H-chain has a central role in regulating iron availability . In turn, this has secondary effects on a number of cellular activities, which include proliferation and resistance to oxidative damage . Moreover, the response to apoptotic stimuli is affected by H-ferritin expression . Altered ferritin L-chain expression has been found in at least two types of genetic disorders, although its role in the determination of the pathology has not been fully clarified . The recent discovery of a new ferritin specific for the mitochondria, which is functionally similar to the H-ferritin, opens new perspectives in the study of the relationships between iron, oxidative damage and free radicals.

Trends Microbiol, 2002 Aug, 10(8), 365 - 70
Is quorum sensing a side effect of diffusion sensing?
Redfield RJ.
Many bacteria appear to communicate by releasing and sensing autoinducer molecules, which are believed to function primarily as sensors of population density . However, this quorum-sensing hypothesis rests on very weak foundations, as neither the need for group action nor the selective conditions required for its evolution have been demonstrated . Here, I argue for a more direct function of autoinducer secretion and response - the ability to determine whether secreted molecules rapidly move away from the cell . This diffusion sensing allows cells to regulate secretion of degradative enzymes and other effectors to minimize losses owing to extracellular diffusion and mixing.

Trends Microbiol, 2002 Aug, 10(8), 361 - 4
The host cytosol: front-line or home front?
O'Riordan M, Portnoy DA.
Intracellular pathogens replicate in modified vacuolar compartments or in the cytosol of host cells . Many pathogenic bacterial species have evolved to modify the host vacuolar environment, but little is known about the mammalian cytosol as a medium for bacterial growth . Recent studies indicate that the cytosol is restrictive for the growth of bacteria other than cytosolic pathogens in contrast to earlier research that provided evidence that any bacteria with access to the cytosol can replicate there . Comparison of these studies suggests that the cytosolic contents of various host cell types can be differentially permissive for bacterial growth, and that both host and bacterial factors are important in determining the ability of particular bacteria to replicate in the cytosol.

J Med Dent Sci, 1999 Dec, 46(4), 155 - 64
The effects on pulp tissue of microleakage in resin composite restorations; Sasafuchi Y et al.; The purpose of this study was to evaluate histopathologically the effect on pulp tissue of microleakage in resin composite restorations . Seventy-two class V cavities were prepared on buccal surfaces of monkeys and divided into 3 groups, F, O, and S . Every cavity was etched with 37% phosphoric acid . In group F cavities, each cavity was restored with photo-curable composite without any dentin adhesives . In group O, the cavities were left unfilled . In group S, each cavity was treated with a dentin adhesive system and restored with a restorative composite . After 3, 30, or 90 days, animals were sacrificed and the subjected teeth were immediately removed, then fixed and decalcified . Following sectioning and staining with hematoxylin and eosin or Taylor's modified bacteria staining, each sample was examined with a light microscope . In most teeth with group S cavities, bacterial invasion was not found indicating excellent marginal sealing . The pulpal reaction was much less than that in other groups . In group F as well as in group O, bacteria were frequently observed in the cavity; however, bacteria penetrated into dentinal tubules more in group F than in group O at 30 and 90 days . A correlation between the presence of bacteria and pulpal inflammation was strongly indicated . It was suggested that a leaky restoration was more harmful to the pulp than an open prepared cavity without restoration.

Drug Ther Bull, 2002 Jul, 40(7), 53 - 4
Getting rid of athlete's foot; Chloroisonicotinamide derivative induces a broad range of disease resistance in rice and tobacco; Microbial Toxicology Laboratory, RIKEN Institute, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198 Japan . nakashi@postman.riken.go.jp

Systemic acquired resistance (SAR) is a potent innate immunity system in plants that is effective against a broad range of pathogens . SAR in dicotyledonous plants such as tobacco and Arabidopsis has been partially elucidated and is mediated by salicylic acid (SA) . However, the SAR mechanism of monocotyledonous rice plants remains to be clarified, although some similarities between SAR mechanisms in both types have been reported . Here we have characterized N-cyanomethyl-2-chloroisonicotinamide (NCI) as an effective SAR inducer in both plant species . Soil drench application of NCI induces a broad range of disease resistance in tobacco and rice and, more specifically, PR gene expression in tobacco . Both SA measurements in wild-type NCI-treated tobacco and pathogenic infection studies using NahG transgenic tobacco plants indicate that NCI-induced resistance enhancement does not require SA . Therefore, it is suggested that NCI induces SAR by triggering signaling at the same level as or downstream of SA accumulation as do both benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester and 2,6-dichloroisonicotinic acid . The fact that all of these chemicals are effective in rice and tobacco suggests that several common components function in disease resistance in both plant species.

J Biochem (Tokyo), 2002 Aug, 132(2), 257 - 63
Effect of organic anions on the photoreaction of photoactive yellow protein; Shimizu N et al.; In order to clarify changes in the structure and surface properties of photoactive yellow protein (PYP) upon light absorption, the spectroscopic properties and solution structure of its photo-intermediate (PYP(M)) were examined in the presence of various anions . At identical ionic strengths, citrate slowed the decay rate of PYP(M) more than acetate . Although the absorption spectrum in the dark was not affected by organic anions, citrate induced a 5-nm blue shift of the absorption maximum for PYP(M) . Solution X-ray scattering experiments indicated that the radius of gyration (Rg) and apparent molecular weight in the dark were constant in all buffer systems . However, the Rg of PYP(M) in citrate buffer at high concentration was 16.2 (+/-0.2) A, while the Rg of PYP(M) in acetate buffer was 15.6 (+/-0.2) A . The apparent molecular weight increased 7% upon PYP(M) formation in citrate buffer at high concentration compared to other conditions . These results suggest that citrate molecules specifically bind to PYP(M) . A cluster of basic amino acid residues with a hydrogen bond donor would be exposed upon PYP(M) formation and responsible for the specific binding of citrate.

J Biochem (Tokyo), 2002 Aug, 132(2), 205 - 10
A role of methionine 100 in facilitating PYP(M)-decay process in the photocycle of photoactive yellow protein; Kumauchi M et al.; PYP (photoactive yellow protein) is a photoreceptor protein, which is activated upon photo-isomerization of the p-coumaric acid chromophore and is inactivated as the chromophore is thermally back-isomerized within a second (in PYP(M)-to-PYP(dark) conversion) . Here we have examined the mechanism of the rapid thermal isomerization by analyzing mutant PYPs of Met100, which was previously shown to play a major role in facilitating the reaction {Devanathan, S . et al . (1998) Biochemistry 37, 11563-11568} . The mutation to Lys, Leu, Ala, or Glu decelerated the dark state recovery by one to three orders of magnitude . By evaluating temperature-dependence of the kinetics, it was found that the retardation resulted unequivocally from elevations of activation enthalpy (DeltaH( double dagger )) but not the other parameters such as activation entropy or heat capacity changes . Another effect exerted by the mutations was an up-shift of the apparent pK(a) of the chromophore {the pK(a) of a titratable group (X) that controls the pK(a) of the chromophore} in the PYP(M)-decay process . The pK(a) up-shift and the DeltaH( double dagger ) elevation show an approximately linear correlation . We, therefore, postulate that the role of Met100 is to reduce the energy barrier of the PYP(M)-decay process by an indirect interaction through X and that the process is thereby facilitated.

Afr J Health Sci, 1994 Nov, 1(4), 147 - 150
Trioxolanes: A new generation of compounds with wide-ranging activities; Koech DK et al.; Direct biological activity of a 1,2,4-trioxolane derivative was assessed in vitro using bacteria and fungi causing common infections . The product was found to be uniformly active against all organisms tested . In addition, it is active against certain tumour cells and protozoa and is also an immunomodulator . These observations are discussed in the light of the product's potential use in the clinical management of conditions in which its use is indicated.

Water Res, 2002 May, 36(10), 2582 - 8
Advanced controlling of anaerobic digestion by means of hierarchical neural networks; Holubar P et al.; In this work several feed-forward back propagation neural networks (FFBP) were trained in order to model, and subsequently control, methane production in anaerobic digesters . To produce data for the training of the neural nets, four anaerobic continuous stirred tank reactors were operated in steady-state conditions at organic loading rates (Br) of about 2 kg m(-3) d(-1) chemical oxygen demand, and disturbed by pulse-like increase of the organic loading rate . For the pulses additional carbon sources like flour, sucrose, 1,2-diethylen glycol or vegetable oil were added to the basic feed, which consisted of surplus and primary sludge of a local waste-water treatment plant, to increase the chemical oxygen demand . Measured parameters were: gas composition, methane production rate, volatile fatty acid concentration, pH, redox potential, volatile suspended solids and chemical oxygen demand of feed and effluent . A hierarchical system of nets was developed and embedded in a decision support system to find out which is the best feeding profile for the next time steps in advance . A 3-3-1 FFBP simulated the pH with a regression coefficient of 0.82 . A 9-3-3 FFBP simulated the volatile fatty acid concentration in the sludge with a regression coefficient of 0.86 . And a 9-3-2 FFBP simulated the gas production and gas composition with a regression coefficient of 0.90 and 0.80, respectively . A lab-scale anaerobic continuous stirred tank reactor controlled by this tool was able to maintain a methane concentration of about 60% at a rather high gas production rate of between 5 and 5.6 m3 m(-3) d(-1).

Thromb Haemost, 2002 Jul, 88(1), 17 - 25
Coagulation and inflammation in acute lung injury; Welty-Wolf KE et al.; The acute respiratory distress syndrome (ARDS) is a severe lung injury in patients with sepsis and other acute inflammatory insults, which is characterized by fibrin deposition in the pulmonary parenchyma, vasculature, and airspaces . Recent evidence suggests that progressive ARDS is closely linked to activation of inflammation and coagulation . Coagulation becomes activated by circulating endotoxin or bacteria, and a procoagulant state develops in the vascular and the alveolar compartments of the lung . This state is Tissue Factor (TF)-dependent and associated with increased elaboration of inflammatory cytokines . A similar procoagulant state is found in bronchoalveolar lavage of patients with ARDS, suggesting that extravascular coagulation contributes to lung inflammation . TF and other coagulation proteins, including Factor Xa, thrombin, and fibrin, also contribute to the pathogenesis of acute lung injury through multi-level interactions with inflammatory effectors, in which these proteins coordinately act as regulators of tissue injury responses . Each coagulation protein has direct and independent effects on inflammatory events that influences lung injury through changes in cytokine elaboration, inflammatory cell migration and activation, surfactant function, and repair mechanisms . New interventional strategies directed at procoagulant activity highlight the importance of the coagulation system to acute lung injury and suggest that blockade of initiation of coagulation may have therapeutic benefit in patients with ARDS.

Clin Orthop, 2002 Aug, (401), 230 - 8
Intraoperative frozen section analysis in revision total joint arthroplasty; Banit DM et al.; A prospective study of the sensitivity, specificity, and predictive values for frozen sections against cultures obtained at the time of revision total joint replacement was done . One hundred twenty-one revision total joint replacements were done in 92 men and 29 women . A positive frozen section with more than 10 polymorphonuclear leukocytes per high power field was compared with the intraoperative cultures . Twenty-one patients who had revision surgery had greater than 10 polymorphonuclear leukocytes per high power field . Of these, 14 patients had positive cultures . The remaining 100 patients had less than 10 polymorphonuclear leukocytes per high power field, but seven had positive cultures . Statistical analysis of frozen sections for all total joint arthroplasties revealed a 67% sensitivity, 93% specificity, 67% positive predictive value, and 93% negative predictive value . Analysis of frozen sections for total hip arthroplasties revealed a 45% sensitivity, 92% specificity, 55% positive predictive value, and 88% negative predictive value . Analysis for total knee arthroplasties revealed 100% sensitivity, 96% specificity, 82% positive predictive value, and 100% negative predictive value . Comparisons of sensitivity, positive predictive value, and negative predictive value between total knee arthroplasty and total hip arthroplasty were significant . The results indicate that the use of intraoperative frozen section analysis with greater than 10 polymorphonuclear leukocytes per high power field as an indication of infection lacks the positive predictive value and sensitivity for accurate determination of prosthetic infection at the time of revision total hip arthroplasty . Frozen sections have an acceptable sensitivity and positive predictive value in total knee arthroplasty . The results of the current study show the limitation of using frozen sections as a diagnostic test for infection in revision total hip arthroplasty.

Plasmid, 2002 May, 47(3), 201 - 9
Plasmid pIP501 encoded transcriptional repressor CopR: single amino acids involved in dimerization are also important for folding of the monomer; Steinmetzer K et al.; CopR is one of the two components regulating replication of plasmid pIP501 . It binds as a preformed dimer at the DNA major groove thereby repressing transcription of the essential repR-mRNA 10-20-fold . Previously, the DNA-binding motif was identified and the location of the dimeric interface was narrowed down . The C-terminal 29 residues were shown to be required exclusively for CopR stability . Here, we report the characterization of four single amino acid exchange mutants at the dimeric interface . All mutants were inactive in copy number control in vivo . Dimerization constants and DNA-binding constants were determined by analytical ultracentrifugation and EMSA, respectively . Denaturation experiments were performed to estimate the protein stability and to calculate DeltaG(0)(H(2)O) . Our data indicate that the four analyzed amino acids are both involved in dimerization and proper folding of the monomer; i.e . they stabilize on the one hand the monomer and on the other hand the dimeric interface.

Biochim Biophys Acta, 2002 Aug 19, 1577(1), 139 - 43
Molecular cloning and characterization of hetR genes from filamentous cyanobacteria; Schiefer W et al.; HetR, a serine type protease, plays an important role in heterocyst differentiation in filamentous cyanobacteria . We isolated and sequenced the hetR genes from different heterocystous and filamentous nonheterocystous cyanobacteria . The hetR gene in the heterocyst forming Anabaena variabilis ATCC 29413 FD was interrupted by interposon mutagenesis (mutant strain WSIII8) . This mutant does not form heterocysts and shows no diazotrophic growth under aerobic conditions . However, under anaerobic N(2)-fixing conditions, the WSIII8 cells are able to grow, and high nitrogenase (Nif2) activity is detectable . Nif2 expression was demonstrated in each vegetative cell of the filament by immunolocalization 4 h after nitrogen step-down.

J Pharm Biomed Anal, 2002 Aug 22, 30(1), 1 - 11
Development of a chiral assay for a novel, nonfluorinated quinolone, PGE-9509924, in dog plasma using high performance liquid chromatography with electrospray tandem mass spectrometry or fluorescence detection; Zoutendam PH et al.; PGE-9509924 is a nonfluorinated quinolone and is active against a variety of susceptible and drug resistant bacteria in vitro and in animal infection models . A method for determining both enantiomers of PGE-9509924 in dog plasma has been developed . The enantiomers are derivatized with a chiral derivatizing agent, (-)-1-(9-fluorenyl)ethyl chloroformate (FLEC) and the resulting diastereomers are separated by reverse phase chromatography . Plasma samples are prepared via solid phase extraction (SPE) in a 96-well format prior to being derivatized . Samples are then analyzed by electrospray-LC/MS/MS with multiple reaction monitoring or by HPLC with fluorescence detection . Results of a side-by-side validation of the method with LC/MS/MS and HPLC/Fl detection are presented . Over the range selected for validation (0.025-10 micro g/ml), both methods give similar results with identical limits of quantitation . Due to the selectivity of LC/MS/MS and the use of a stable-isotopically labeled internal standard, significantly shorter chromatographic runtimes are achieved with LC/MS/MS, making it the method of choice for sample analysis.

Immunity, 2002 Jul, 17(1), 107 - 15
Secretory component: a new role in secretory IgA-mediated immune exclusion in vivo; Phalipon A et al.; Secretory immunoglobulin (Ig) A (SIgA) is essential in protecting mucosal surfaces . It is composed of at least two monomeric IgA molecules, covalently linked through the J chain, and secretory component (SC) . We show here that a dimeric/polymeric IgA (IgA(d/p)) is more efficient when bound to SC in protecting mice against bacterial infection of the respiratory tract . We demonstrate that SC ensures, through its carbohydrate residues, the appropriate tissue localization of SIgA by anchoring the antibody to mucus lining the epithelial surface . This in turn impacts the localization and the subsequent clearance of bacteria . Thus, SC is directly involved in the SIgA function in vivo . Therefore, binding of IgA(d/p) to SC during the course of SIgA-mediated mucosal response constitutes a crucial step in achieving efficient protection of the epithelial barrier by immune exclusion.

Zoolog Sci, 2002 Jul, 19(7), 741 - 6
Encystment-inducing factors in the ciliate Euplotes elegans; Tomaru A; Although starvation is considered one of the most important induces of ciliate encystment, its nature has been unclear . Euplotes is a well-known ciliate genus, but the relationship in Euplotes between encystment and food has not been reported . The encystment of Euplotes elegans is facilitated when it is transferred to Chalkley's solution without bacteria as food . A higher ciliate density also facilitates encystment . Thus, starvation and ciliate density needed to be examined . Ciliates were inoculated into 3 treatments: Chalkley's solution with formaldehyde-fixed bacteria as nutritive particles (FFB group), with polystyrene latex particles as non-nutritive particles (PLP group), and without particles (control group) . Cysts appeared fastest and ciliate numbers increased in the FFB group . Although the encystment kinetics of the PLP group was similar to that of the control group, the encystment rate of the PLP group was lower than that of the control group in the earliest phase . This suggests that the ciliates were temporarily deceived into feeding on PLP, because they had food vacuoles containing PLP during the earliest phase of incubation . A cell-free old culture solution from a stationary phase, which probably contained excreted substances from high-density ciliates, also facilitated encystment.

J Leukoc Biol, 2002 Aug, 72(2), 305 - 11
Differential involvement of CD40, CD80, and major histocompatibility complex class I molecules in cytotoxicity induction and interferon-gamma production by human natural killer effectors; Terrazzano G et al.; Natural killer (NK) cells are physiologically involved in the immune response against viruses, intracellular bacteria, and parasites as well as against malignant diseases . In addition to the cytotoxic activity, NK lymphocytes mediate a variety of homeostatic effects by producing cytokines . This study focused on the differential role of CD40 and CD80 costimulatory molecules and major histocompatibility complex class I (MHC-I) antigens in the regulation of cytotoxicity and of interferon (IFN)-gamma secretion of resting and interleukin (IL)-2-activated human NK cells . CD40 and CD80 molecules were observed to play a specific role in the induction of cytotoxic function but not in IFN-gamma production of IL-2-activated NK effectors . In addition, a critical role of CD94-dependent MHC-I recognition for the regulation of IFN-gamma production and target lysis was demonstrated . These data provide a possible mechanism underlying functional interactions between NK lymphocytes and CD40/CD80-expressing cell targets, as represented by dendritic cells.

Immunol Invest, 2002 May, 31(2), 107 - 20
Occurrence, properties, and function of asymmetric IgG molecules isolated from non-immune sera; Canellada A et al.; We have previously demonstrated that 10-20% of the IgG isolated from non-immune sera is asymmetrically glycosylated, in such a way that it fails to trigger immune effector mechanisms . As a result, a major portion of the non-immune asymmetric IgG molecules of the host could be self-specific, acting as auto-protective antibodies . In order to test this hypothesis, we investigated whether asymmetric IgG molecules are capable of recognizing self-antigens . About 40% of F(ab')2 fragment from normal rat IgG was able to react specifically with autologous rat cells . Moreover, upon being purified from normal rat sera, 78% of the asymmetric IgG sub-population showed self-reactivity . We demonstrated that about 14% of rat asymmetric IgG-F(ab')2 fragments was able to react with bacteria isolated from the intestine of uninfected rats . Lastly, in order to test whether there is a correlation between the decline of immune responses during ageing and asymmetric antibody production, we assayed IgG isolated from sera of young and old rats . There was an increase in the asymmetric:symmetric IgG ratio with ageing . We therefore suggest that asymmetric antibodies may exert a beneficial action by protecting self-antigens as well as normal intestinal flora from a deleterious immune response.

Int J Syst Evol Microbiol, 2002 Jul, 52(Pt 4), 1397 - 404
Phylogenetic analyses of nitrogen-fixing cyanobacteria from the Baltic Sea reveal sequence anomalies in the phycocyanin operon; Janson S et al.; The examination of molecular phylogenies of cyanobacteria and other micro-organisms is increasing dramatically . The use of a single locus in these studies leaves the resulting phylogenies unconfirmed . In this study, the partial sequences of two loci containing segments of protein-encoding genes, the hetR and the phycocyanin locus (PC-IGS), were examined . Laboratory strains and natural populations of the heterocyst-forming cyanobacteria Anabaena, Aphanizomenon and Nodularia from the Baltic Sea were used, in total 41 sequences were determined and their phylogenies were analysed with maximum-likelihood methods . The hetR phylogenies suggested that the planktonic Aphanizomenon and Nodularia each comprise one species, while there were numerous Anabaena species present in the Baltic Sea . In the case of Nodularia, the PC-IGS phylogenies were incongruent with this and suggested that several lineages of Nodularia plankton species existed . In the hetR phylogeny, the floating and nodularin-producing strains of Nodularia were grouped together . For both the hetR and PC-IGS loci of cultured species of Nodularia their molecular phylogeny did not correspond well with the affiliation suggested by morphology . In sequences derived from species of Anabaena and Aphanizomenon the PC-IGS and hetR phylogenies were congruent, suggesting that Aphanizomenon sp . from the Baltic Sea is genetically distinct from both Aphanizomenon flos-aquae from lakes and Aphanizomenon sp . TR183 from the Baltic Sea . In both Nodularia and Anabaena/Aphanizomenon, the PC-IGS sequences showed a significant degree of either recombination events or selection, while none was detected within the hetR sequences . This is the first study comprising the phylogenies of multiple loci from all heterocystous cyanobacteria from the Baltic Sea and shows that earlier results using the PC-IGS locus should be interpreted cautiously in the absence of a confirmation using a second locus.

Int J Syst Evol Microbiol, 2002 Jul, 52(Pt 4), 1305 - 8
Reclassification of the only species of the genus Desulfomonas, Desulfomonas pigra, as Desulfovibrio piger comb . nov; Loubinoux J et al.; The growth characteristics, DNA G+C content and sequences of 16S rDNA and the transcribed 16S-23S rDNA internal spacer were determined for Desulfomonas pigra ATCC 29098T, Desulfovibrio desulfuricans subsp . desulfuricans strains Essex 6T (= ATCC 29577T) and MB (= ATCC 27774) and 'Desulfovibrio fairfieldensis' ATCC 700045 . Despite phenotypic differences (shape and motility) between Desulfomonas pigra and Desulfovibrio strains, the molecular analysis suggests that Desulfomonas pigra should be reclassified within the genus Desulfovibrio . Thus, the reclassification is proposed of Desulfomonas pigra, the type and only species of the genus, as Desulfovibrio piger comb . nov., which implies the emendation of the description of the genus Desulfovibrio.

J Environ Health, 2002 Jul-Aug, 65(1), 16 - 23, 28; quiz 31-2
Outbreaks in drinking-water systems, 1991-1998; Craun GF et al.; During 1991-1998, 126 outbreaks, 429,021 cases of illness, 653 hospitalizations, and 58 deaths were reported in public and individual water systems in 41 states and three U.S . territories . A bacterial, viral, or protozoan etiology was identified in 41 percent of the outbreaks, and a chemical contaminant was identified in 18 percent . No etiological agent was determined in the remaining outbreaks . Important causes of outbreaks included contamination of untreated groundwater, inadequate disinfection of groundwater, and distribution system deficiencies, especially cross-connections and corrosive water . The responsible pathogen or chemical was identified in water samples collected during 31 percent of the reported outbreaks . Coliform bacteria were detected in water samples collected during the investigation of infectious-disease outbreaks in 83 percent of noncommunity and 46 percent of community water systems, but very few of these systems had exceeded the U.S . Environmental Protection Agency's maximum limit for total coliforms in the 12 months before the outbreak.

Cryo Letters, 2000 Sep, 21(5), 289 - 296
The history of cold hardiness research in terrestrial arthropods; S mme L; R.A.F . Reaumur in 1736 was the first entomologist to observe that some insects can tolerate freezing, while others cannot . The first reviews on insect cold hardiness were published by P . Bachmetjew who also discovered supercooling in insects . Authors like W . Robinson realised that piercing the cuticle changed the supercooling capacity and N.M . Payne pointed out that there are great seasonal variations in insect cold hardiness . In the early literature, references were frequently made to plant cold hardiness, in which theories on tolerance to freezing were more elaborated . A modern approach to the studies of insect cold hardiness was initiated by R.W . Salt . The number of reports increased enormously in the 1960's and 1970's . During the last 20 to 30 years new insight has appeared from studies on ice nucleators, antifreeze proteins, ice-nucleating bacteria, desiccation and biochemistry of cryoprotectants.

Minerva Stomatol, 2002 Jun, 51(6), 231 - 9
{Prevention of periodontopathy and oral mucositis during antineoplastic chemotherapy . Clinical study}; Luglie PF et al.; BACKGROUND: Oral mucositis is a common side effect of chemotherapy, with a multifactorial etiology: the direct toxicity of cancer therapy on the normal cells, reduced immunitary defences, presence of bacteria in the oral cavity . The aim of this study is to assess the clinical effectiveness of a preventive protocol of oral mucositis and periodontopathy during antineoplastic chemotherapy . METHODS: The design of the study was a longitudinal evaluation of 30 patients undergoing antineoplastic chemotherapy at the out-patients Department of Oncology of the University of Sassari . The study lasted one year and was carried out at the Dentistry Department of the University of Sassari . The patients were motivated to home oral hygiene, underwent professional oral hygiene and clorexidine rinses were prescribed . Visible plaque index (VPI) and gingival bleeding index (GBI) were taken from each patient as periodontal indices, and the state of the mucosa was evaluated according to the WHO recommendations (1975) . The control group was composed by 33 patients . RESULTS: The values of the bleeding and plaque indices were considerably diminished between the first and the last visit, in nearly all the patients; the incidence of oral mucositis in the treated group was 20%, while in the control group it was 66% . 5-fluoruracil was always involved . CONCLUSIONS: According to the results observed, the conclusion is drawn that the professional and home oral hygiene and the use of clorexidine, can reduce the incidence of oral mucositis as a side effect of antineoplastic chemotherapy.

Annu Rev Phytopathol, 2002, 40, 381 - 410 Epub 2002 Feb 20.
Use of multiline cultivars and cultivar mixtures for disease management; Mundt CC; The usefulness of mixtures (multiline cultivars and cultivar mixtures) for disease management has been well demonstrated for rusts and powdery mildews of small grain crops . Such mixtures are more useful under some epidemiological conditions than under others, and experimental methodology, especially problems of scale, may be crucial in evaluating the potential efficacy of mixtures on disease . There are now examples of mixtures providing both low and high degrees of disease control for a wide range of pathosystems, including crops with large plants, and pathogens that demonstrate low host specificity, or are splash dispersed, soilborne, or insect vectored . Though most analyses of pathogen evolution in mixtures consider static costs of virulence to be the main mechanism countering selection for pathogen complexity, many other potential mechanisms need to be investigated . Agronomic and marketing considerations must be carefully evaluated when implementing mixture approaches to crop management . Practical difficulties associated with mixtures have often been overestimated, however, and mixtures will likely play an increasingly important role as we develop more sustainable agricultural systems.

Annu Rev Phytopathol, 2002, 40, 349 - 79 Epub 2002 Feb 20.
Pathogen population genetics, evolutionary potential, and durable resistance; McDonald BA et al.; We hypothesize that the evolutionary potential of a pathogen population is reflected in its population genetic structure . Pathogen populations with a high evolutionary potential are more likely to overcome genetic resistance than pathogen populations with a low evolutionary potential . We propose a flexible framework to predict the evolutionary potential of pathogen populations based on analysis of their genetic structure . According to this framework, pathogens that pose the greatest risk of breaking down resistance genes have a mixed reproduction system, a high potential for genotype flow, large effective population sizes, and high mutation rates . The lowest risk pathogens are those with strict asexual reproduction, low potential for gene flow, small effective population sizes, and low mutation rates . We present examples of high-risk and low-risk pathogens . We propose general guidelines for a rational approach to breed durable resistance according to the evolutionary potential of the pathogen.

J Dent Res, 2002 Aug, 81(8), 556 - 60
Bonding of self-etch and total-etch adhesives to carious dentin; Yoshiyama M et al.; Carious dentin is partially demineralized and contains mineral crystals in the tubules . This may permit the deeper etching of intertubular dentin but prevent resin tag formation during bonding . We hypothesize that resin adhesives will produce lower bond strengths to caries-infected and caries-affected dentin compared with normal dentin . We tested this by measuring the microtensile bond strength of a total-etch adhesive and an experimental self-etching adhesive (ABF) to caries-infected, caries-affected, and sound dentin and by correlating those results with ultrastructural observations . The bond strengths of both adhesives to sound dentin were significantly (p < 0.05) higher than those to caries-affected dentin, which, in turn were significantly (p < 0.05) higher than those to caries-infected dentin . For both adhesives, hybrid layers in caries-affected dentin were thicker but more porous than those in sound dentin . The lower bond strengths may be due to the lower tensile strength of caries-affected dentin . Clinically, this may not be a problem, since such lesions are normally surrounded by normal dentin or enamel.

J Exp Bot, 2002 Aug, 53(375), 1831 - 2
Dodder infection induces the expression of a pathogenesis-related gene of the family PR-10 in alfalfa; Borsics T et al.; A full-length cDNA, PPRG2, representing a gene highly expressed in dodder (Cuscuta trifolii Bab et . Gibs)-infected alfalfa (Medicago sativa L.) stems was isolated by differential screening . The predicted protein contains 157 amino acids and belongs to the PR-10 family of the pathogenesis-related genes with putative ribonuclease activities . Northern hybridizations showed that PPRG2 is transcribed in root and crops of uninfected alfalfa and is induced not only by dodder attack but also by bacterial infections and a large variety of environmental stresses.

Appl Environ Microbiol, 2002 Aug, 68(8), 4153 - 7
Worldwide distribution of Nitrosococcus oceani, a marine ammonia-oxidizing gamma-proteobacterium, detected by PCR and sequencing of 16S rRNA and amoA genes; Ward BB et al.; Diversity of cultured ammonia-oxidizing bacteria in the gamma-subdivision of the Proteobacteria was investigated by using strains isolated from various parts of the world ocean . All the strains were very similar to each other on the basis of the sequences of both the 16S rRNA and ammonia monooxygenase genes and could be characterized as a single species . Sequences were also cloned directly from environmental DNA from coastal Pacific and Atlantic sites, and these sequences represented the first Nitrosococcus oceani-like sequences obtained directly from the ocean . Most of the environmental sequences clustered tightly with those of the cultivated strains, but some sequences could represent new species of NITROSOCOCCUS: These findings imply that organisms similar to the cultivated N . oceani strains have a worldwide distribution.

Appl Environ Microbiol, 2002 Aug, 68(8), 4074 - 80
Internal spatiotemporal population dynamics of infection with three Wolbachia strains in the adzuki bean beetle, Callosobruchus chinensis (Coleoptera: Bruchidae); Ijichi N et al.; The adzuki bean beetle, Callosobruchus chinensis, is infected with three distinct lineages of endosymbiotic bacteria belonging to the genus Wolbachia, which were designated wBruCon, wBruOri, and wBruAus . In an attempt to understand the mechanisms underlying the infection with these three organisms, the spatiotemporal infection dynamics of the three Wolbachia strains was investigated in detail by using a quantitative PCR technique . During the development of C . chinensis, the wBruCon, wBruOri, and wBruAus infection levels consistently increased but the growth patterns were different . The levels of infection plateaued at the pupal stage at approximately 3 x 10(8), 2 x 10(8), and 5 x 10(7) wsp copy equivalents per insect for wBruCon, wBruOri, and wBruAus, respectively . At the whole-insect level, the population densities of the three Wolbachia types did not show remarkable differences between adult males and females . At the tissue level, however, the total densities and relative levels of the three Wolbachia types varied significantly when different tissues and organs were compared and when the same tissues derived from males and females were compared . The histological data obtained by in situ hybridization and electron microscopy were concordant with the results of quantitative PCR analyses . Based on the histological data and the peculiar Wolbachia composition commonly found in nurse tissues and oocytes, we suggest that the Wolbachia strains are vertically transmitted to oocytes not directly, but by way of nurse tissue . On the basis of our results, we discuss interactions among the three coinfecting Wolbachia types, reproductive strategies of Wolbachia, and factors involved in the different cytoplasmic incompatibility phenotypes.

J Appl Microbiol, 2002, 93(2), 235 - 40
Applied technique for increasing calicivirus detection in shellfish extracts; Burkhardt W 3rd et al.; AIMS: Optimal detection of enteric RNA viruses in clinical, environmental, and food products using reverse transcription-PCR (RT-PCR) when inhibitory substances in extracted sample materials are present . METHODS AND RESULTS: We adapted a device for detection of RNA viruses in plant tissues and insects to detect a calicivirus strain (San Miguel sea lion virus, serotype 17) in water and oyster tissue extracts . This single, compartmentalized tube-within-a-tube (TWT) device for RT-PCR-nested PCR was compared to a conventional protocol of RT-PCR-nested PCR . In the presence of 100 mg of shellfish tissue extract equivalent, this TWT device decreases the calicivirus assay detection limit 10-fold over that of conventional RT-PCR-nested PCR while maintaining an identical detection limit of viral nucleic acid suspended in water . Both the conventional and TWT methods estimated the total particle-to-infectious particle ratio for this strain of calicivirus at approximately 40 : 1 . CONCLUSIONS: We believe that the TWT device with appropriate RT-PCR primers will decrease the detection limit for other calicivirus strains and RNA viruses in shellfish tissue extracts . SIGNIFICANCE AND IMPACT OF THE STUDY: We believe that the TWT approach is applicable to other situations where RT and/or PCR inhibitory materials are present or nucleic acid targets of bacteria or viruses are at low levels in extracts of food products or clinical specimens.

Water Res, 2002 Jun, 36(11), 2681 - 8
"Weak" ultrasonic pre-treatment on anaerobic digestion of flocculated activated biosolids; Chu CP et al.; This study examined how "weak" ultrasonic pre-treatment affects anaerobic digestion of waste biosolids, treated with a cationic polyelectrolyte flocculant . In relation to pre-treatment, the term "weak" used refers to the fact that the total ultrasonic energy input to biosolids is insufficient to fully disrupt its floc structure or the cell walls, as described in the literature . Methane production potential, floc characteristics (size, morphology and zeta-potential) and process parameters (chemical oxygen demands and oxidative-reductive potentials) were monitored, as the digestion was tested . The presence of polyelectrolyte flocculants enhanced methane production within 6 days of digestion (phase I), but inhibited the digestion thereafter (phase II) . Following pre-treatment by sonication (0.33 W/mL, 20 min), the methane productions of both original and flocculated biosolids significantly increased . The underlying mechanisms of weak ultrasonic pre-treatment are discussed.

Nat Immunol, 2002 Aug, 3(8), 715 - 20
Asthma: an epidemic of dysregulated immunity; Umetsu DT et al.; The remarkable increase in asthma prevalence that has occurred over the last two decades is thought to be caused by changes in the environment due to improved hygiene and fewer childhood infections . However, the specific infections that limit T helper type 2 (T(H)2)-biased inflammation and asthma are not fully known . Infectious organisms, including commensal bacteria in the gastrointestinal tract and hepatitis A virus, may normally induce the development of regulatory T (T(R)) cells and protective immunity that limit airway inflammation and promote tolerance to respiratory allergens . In the absence of such infections, T(H)2 cells--which are developmentally related to T(R) cells--develop instead and coordinate the development of asthmatic inflammation.

J Biol Chem, 2002 Oct 4, 277(40), 36931 - 9 Epub 2002 Jul 26.
In vitro versus in vivo cellulose microfibrils from plant primary wall synthases: structural differences; Lai-Kee-Him J et al.; Detergent extracts of microsomal fractions from suspension cultured cells of Rubus fruticosus (blackberry) were tested for their ability to synthesize in vitro sizable quantities of cellulose from UDP-glucose . Both Brij 58 and taurocholate were effective and yielded a substantial percentage of cellulose microfibrils together with (1-->3)-beta-d-glucan (callose) . The taurocholate extracts, which did not require the addition of Mg(2+), were the most efficient, yielding roughly 20% of cellulose . This cellulose was characterized after callose removal by methylation analysis, electron microscopy, and electron and x-ray synchrotron diffractions; its resistance toward the acid Updegraff reagent was also evaluated . The cellulose microfibrils synthesized in vitro had the same diameter as the endogenous microfibrils isolated from primary cell walls . Both polymers diffracted as cellulose IV(I), a disorganized form of cellulose I . Besides these similarities, the in vitro microfibrils had a higher perfection and crystallinity as well as a better resistance toward the Updegraff reagent . These differences can be attributed to the mode of synthesis of the in vitro microfibrils that are able to grow independently in a neighbor-free environment, as opposed to the cellulose in the parent cell walls where new microfibrils have to interweave with the already laid polymers, with the result of a number of structural defects.

EMBO J, 2002 Aug 1, 21(15), 4145 - 53
Crystal structure of an mRNA-binding fragment of Moorella thermoacetica elongation factor SelB; Selmer M et al.; SelB is an elongation factor needed for the co-translational incorporation of selenocysteine . Selenocysteine is coded by a UGA stop codon in combination with a specific downstream mRNA hairpin . In bacteria, the C-terminal part of SelB recognizes this hairpin, while the N-terminal part binds GTP and tRNA in analogy with elongation factor Tu (EF-Tu) . We present the crystal structure of a C-terminal fragment of SelB (SelB-C) from Moorella thermoacetica at 2.12 A resolution, solved by a combination of selenium and yttrium multiwavelength anomalous dispersion . This 264 amino acid fragment contains the entire C-terminal extension beginning after the EF-Tu-homologous domains . SelB-C consists of four similar winged-helix domains arranged into the shape of an L . This is the first example of winged-helix domains involved in RNA binding . The location of conserved basic amino acids, together with data from the literature, define the position of the mRNA-binding site . Steric requirements indicate that a conformational change may occur upon ribosome interaction . Structural observations and data in the literature suggest that this change happens upon mRNA binding.

J Mol Biol, 2002 Aug 9, 321(2), 215 - 34
Modeling a minimal ribosome based on comparative sequence analysis; Mears JA et al.; We have determined the three-dimensional organization of ribosomal RNAs and proteins essential for minimal ribosome function . Comparative sequence analysis identifies regions of the ribosome that have been evolutionarily conserved, and the spatial organization of conserved domains is determined by mapping these onto structures of the 30S and 50S subunits determined by X-ray crystallography . Several functional domains of the ribosome are conserved in their three-dimensional organization in the Archaea, Bacteria, Eucaryotic nuclear, mitochondria and chloroplast ribosomes . In contrast, other regions from both subunits have shifted their position in three-dimensional space during evolution, including the L11 binding domain and the alpha-sarcin-ricin loop (SRL) . We examined conserved bridge interactions between the two ribosomal subunits, giving an indication of which contacts are more significant . The tRNA contacts that are conserved were also determined, highlighting functional interactions as the tRNA moves through the ribosome during protein synthesis . To augment these studies of a large collection of comparative structural models sampled from all major branches on the phylogenetic tree, Caenorhabditis elegans mitochondrial rRNA is considered individually because it is among the smallest rRNA sequences known . The C.elegans model supports the large collection of comparative structure models while providing insight into the evolution of mitochondrial ribosomes.

Phys Rev Lett . 2002 Jul 29;89(5):058101 . Epub 2002 Jul 15.
Hydrodynamic fluctuations and instabilities in ordered suspensions of self-propelled particles; Aditi Simha R et al.; We construct the hydrodynamic equations for suspensions of self-propelled particles (SPPs) with spontaneous orientational order, and make a number of striking, testable predictions: (i) Nematic SPP suspensions are always absolutely unstable at long wavelengths . (ii) SPP suspensions support novel propagating modes at long wavelengths, coupling orientation, flow, and concentration . (iii) In a wave number regime accessible only in low Reynolds number systems such as bacteria, polar-ordered suspensions are invariably convectively unstable . (iv) The variance in the number N of particles, divided by the mean <N>, diverges as <N >(2/3 ) in polar-ordered SPP suspensions.

J Med Entomol, 2002 Jul, 39(4), 562 - 7
Searching for Wolbachia (Rickettsiales: Rickettsiaceae) in mosquitoes (Diptera: Culicidae): large polymerase chain reaction survey and new identifications; Ricci I et al.; Bacteria of the genus Wolbachia constitute a group of intracellular and maternally inherited micro-organisms that are widespread in arthropods, inducing several reproductive disorders such as cytoplasmic incompatibility in their hosts . Considering relevant biological implications related to the presence of Wolbachia in several insect orders, for example its potential role as mechanism for rapid speciation and as vehicle to drive genetic markers in wild populations of vectors of medical and veterinary interest, we carried out an extensive polymerase chain reaction survey to detect Wolbachia in several species of mosquito belonging to genera involved in the transmission of pathogens . Five species out of 26 tested have shown to be infected; for four of them this is the first evidence of the Wolbachia infection . A phylogenetic analysis was also performed, positioning the five Wolbachia strains in the phyletic subdivision B.

Neonatal Netw, 2001 Aug, 20(5), 21 - 8
Systemic inflammatory response syndrome; Botwinski CA; Despite advances in perinatal care in the past decade, sepsis and its complications continue to present problems for the neonate, remaining a major cause of neonatal morbidity and mortality . Sepsis research is focusing on how the neonate (host) responds to bacteria . The newborn may develop a systemic reaction to bacteria that induces the release of substances known as inflammatory mediators . Termed the systemic inflammatory response syndrome (SIRS), this reaction is believed to be responsible for the signs and symptoms of sepsis . This article introduces the neonatal nurse to SIRS, providing an overview of various inflammatory mediators and cytokines, their clinical consequences, and potential new therapies in the management of SIRS.

J Contam Hydrol, 2002 Jul, 57(1-2), 61 - 80
Natural attenuation of chlorinated solvents at Area 6, Dover Air Force Base: groundwater biogeochemistry; Witt ME et al.; Monitored natural attenuation (MNA) has recently emerged as a viable groundwater remediation technology in the United States . Area 6 at Dover Air Force Base (Dover, DE) was chosen as a test site to examine the potential for MNA of tetrachloroethene (PCE) and trichloroethene (TCE) in groundwater and aquifer sediments . A "lines of evidence" approach was used to document the occurrence of natural attenuation . Chlorinated hydrocarbon and biogeochemical data were used to develop a site-specific conceptual model where both anaerobic and aerobic biological processes are responsible for the destruction of PCE, TCE, and daughter metabolites . An examination of groundwater biogeochemical data showed a region of depleted dissolved oxygen with elevated dissolved methane and hydrogen concentrations . Reductive dechlorination likely dominated in the anaerobic portion of the aquifer where PCE and TCE levels were observed to decrease with a simultaneous increase in cis-1,2-dichloroethene (cis-DCE), vinyl chloride (VC), ethene, and dissolved chloride . Near the anaerobic/ aerobic interface, concentrations of cis-DCE and VC decreased to below detection limits, presumably due to aerobic biotransformation processes . Therefore, the contaminant and daughter product plumes present at the site appear to have been naturally atteuated by a combination of active anaerobic and aerobic biotransformation processes.

Acta Orthop Scand, 2002 Jun, 73(3), 317 - 20
The real contamination of femoral head allografts washed with pulse lavage; Salmela PM et al.; At the Tampere Bone Bank, all the discarded femoral heads from September 1997 to May 2000 were recultured . The grafts had been washed with pulse lavage at harvesting . 48 grafts had been discarded because of a positive culture and 85 with negative cultures because of positive or insufficient serological information . The femoral heads were split into halves, which were recultured as a whole in thioglycolate broth for 14 days . The contamination of previously culture positive and negative femoral heads did not differ . In only 2 cases did we find the same type of bacteria in the primary as in the new culture . Most of the primary contamination proved to be false positive . The real contamination seems to be very low, at least after pulse lavage washing of the femoral head.

OMICS, 2002, 6(2), 187 - 98
Cross-species conservation of SEL1L, a human pancreas-specific expressing gene; Biunno I et al.; SEL1L is a recently cloned and organ-specific expressing human gene whose function is still at an embryonic stage but displays several interesting characteristics, among which a remarkable cross-species conservation . During evolution, the gene structural complexity increased, suggesting a diversification of its function; however, several amino acid motifs remain perfectly conserved from the bacteria to the human protein . SEL1L is the human ortholog of the C . elegans gene sel-1; the latter is implicated in the negative regulation of LIN-12/GLP-1/Notch receptor proteins . These receptor proteins play fundamental roles in signal transduction pathways and are key players in cell fate determination during the development of various organs . Studies in model organisms, such as C . elegans, helped to illuminate fundamental mechanisms involved in normal cellular functions and human diseases . This paper describes the conserved nature of SEL1L across a wide range of species suggesting, that the encoded protein most likely exerts a very important biological function; it may belong to a subclass of genes considered to be "essential."

Rev Med Liege, 2002 May, 57(5), 324 - 9
{Origin and treatment of bad breath}; Debaty B et al.; Halitosis affects more than 60% of the population . In about 8% of the cases, halitosis is related to an ENT pathology, and in less than 1% to gastric dysfunction . Ninety percent of these problems are associated to an oral disease . Gram-bacteria are often responsible of bad breath . They transform some amino-acids in volatile sulphur compounds . These bacteria are, also, directly associated with periodontal diseases which affect a major part of the adult population . These diseases are the most important cause of tooth loss after the age of thirty-five, with progressive destruction of supporting tissues of the teeth.

Annu Rev Microbiol, 2002, 56, 539 - 65 Epub 2002 Jan 30.
Cross-species infections and their analysis; Tan MW; The ability of certain pathogens to infect multiple hosts has led to the development of genetically tractable nonvertebrate hosts to elucidate the molecular mechanisms of interactions between these pathogens and their hosts . The use of plant, insect, nematode, and protozoan hosts to study human pathogens has facilitated the elucidation of molecular nature of pathogenesis and host responses . Analyses of virulence of multihost pathogens on their respective hosts revealed that pathogens utilize many universal offensive strategies to overcome host defenses, irrespective of the evolutionary lineage of the host . Likewise, genetic dissections of the defense response of the nonvertebrate hosts have also shown that key features underlying host defense responses are highly conserved . This review summarizes how the information gained from the analysis of cross-species infections contributes to our understanding of host-pathogen interactions.

Annu Rev Microbiol, 2002, 56, 521 - 38 Epub 2002 Jan 30.
Common principles in viral entry; Poranen MM et al.; Viruses occur throughout the biosphere . Cells of Eukarya, Bacteria, and Archaea are infected by a variety of viruses that considerably outnumber the host cells . Although viruses have adapted to different host systems during evolution and many different viral strategies have developed, certain similarities can be found . Viruses encounter common problems during their entry process into the host cells, and similar strategies seem to ensure, for example, that the movement toward the site of replication and the translocation through the host membrane occur . The penetration of the host cell's external envelope involves, across the viral world, either fusion between two membranes, channel formation through the host envelope, disruption of the membrane vesicle, or a combination of these events . Endocytic-type events may occur during the entry of a bacterial virus as well as during the entry of an animal virus; the same applies for membrane fusion.

J Bacteriol, 2002 Aug, 184(16), 4430 - 41
Genes of de novo pyrimidine biosynthesis from the hyperthermoacidophilic crenarchaeote Sulfolobus acidocaldarius: novel organization in a bipolar operon; Thia-Toong TL et al.; Sequencing a 8,519-bp segment of the Sulfolobus acidocaldarius genome revealed the existence of a tightly packed bipolar pyrimidine gene cluster encoding the enzymes of de novo UMP synthesis . The G+C content of 35.3% is comparable to that of the entire genome, but intergenic regions exhibit a considerably lower percentage of strong base pairs . Coding regions harbor the classical excess of purines on the coding strand, whereas intergenic regions do not show this bias . Reverse transcription-PCR and primer extension experiments demonstrated the existence of two polycistronic messengers, pyrEF-orf8 and pyrBI-orf1-pyrCD-orf2-orf3-orf4, initiated from a pair of divergent and partially overlapping promoters . The gene order and the grouping in two wings of a bipolar operon constitute a novel organization of pyr genes that also occurs in the recently determined genome sequences of Sulfolobus solfataricus P2 and Sulfolobus tokodaii strain 7; the configuration appears therefore characteristic of Sulfolobus . The quasi-leaderless pyrE and pyrB genes do not bear a Shine-Dalgarno sequence, whereas the initiation codon of promoter-distal genes is preceded at an appropriate distance by a sequence complementary to the 3' end of 16S rRNA . The polycistronic nature of the pyr messengers and the existence of numerous overlaps between contiguous open reading frames suggests the existence of translational coupling . pyrB transcription was shown to be approximately twofold repressed in the presence of uracil . The mechanism underlying this modulation is as yet unknown, but it appears to be of a type different from the various attenuation-like mechanisms that regulate pyrB transcription in bacteria . In contrast, the pyrE-pyrB promoter/control region harbors direct repeats and imperfect palindromes reminiscent of target sites for the binding of a hypothetical regulatory protein(s).

J Bacteriol, 2002 Aug, 184(16), 4420 - 9
Developmental regulation of the Streptomyces lividans ram genes: involvement of RamR in regulation of the ramCSAB operon; Keijser BJ et al.; Streptomycetes are filamentous soil bacteria that produce spores through a complex process of morphological differentiation . The ram cluster plays an important part during the development . The ram genes encode a membrane-bound kinase (RamC), a small protein (RamS), components of an ABC transporter (RamAB), and a response regulator (RamR) . While the introduction of an extra copy of the ram cluster accelerates development in Streptomyces lividans, ramABR disruption mutants are unable to produce aerial hyphae and spores . The developmental regulation of ram gene transcription was analyzed . Transcription of the ram genes occurred only on solid rich media and not on minimal media . The ramR gene is transcribed from a single promoter during all growth stages, with the highest levels during aerial growth . The ramCSAB genes comprise one operon and are transcribed from one principal promoter, P1, directly upstream of ramC . Transcription of ramCSAB was already observed during vegetative growth, but was strongly upregulated upon initiation of formation of aerial hyphae and was decreased during late stages of development . A large inverted repeat located downstream of ramS terminated the majority of transcripts . The introduction of ramR on a multicopy vector in S . lividans strongly induced P1 activity, while disruption of this regulator eliminated all P1 promoter activity . This shows that ramR is a crucial activator of ramCSAB transcription . Importantly, in bldA, bldB, bldD, or bldH mutants, ramR and ramCSAB are not transcribed, while ram gene transcription was observed in the earliest whi mutant, whiG . This indicates that the transcription of the ram genes marks the transition from vegetative to aerial growth.

Dig Dis Sci, 2002 Jul, 47(7), 1438 - 46
Epithelial induction of serum amyloid A in experimental mucosal inflammation; Fukushima K et al.; We previously demonstrated epithelial induction of serum amyloid A in germ-free mice inoculated with luminal bacteria . The aims of the present study were to investigate the role of luminal bacteria and mucosal inflammation in epithelial expression of this acute-phase protein using germ-free and dextran sulfate sodium-treated mice in vivo and HT29 cells in vitro . Immunoreactivity for serum amyloid A was detected in the epithelium of esophagus, stomach, duodenum and rectum regardless of the presence or absence of luminal bacteria . Administration of dextran sulfate sodium resulted in colonic epithelial induction of serum amyloid A at the mRNA and protein levels in parallel with the progression of mucosal inflammation . Epithelial induction of serum amyloid A is possibly relevant to mucosal inflammation because that was observed in bacteria-reconstituted and dextran sulfate sodium-induced colitis in vivo and because interleukin-beta and lipopolysaccharide induced its mRNA in vitro.

Dig Dis Sci, 2002 Jul, 47(7), 1432 - 7
Impaired humoral immune response against mycobacterial 65-kDa heat shock protein (HSP65) in patients with inflammatory bowel disease; Bene L et al.; Since only scarce data are available on the immune response against heat shock proteins (HSP) in inflammatory bowel disease (IBD), we have measured with an ELISA method serum levels of IgG, IgA, and IgM antibodies to mycobacterial HSP65 and human HSP60 in 66 patients with Crohn's disease (CD), 42 patients with ulceratiVe colitis (UC), and 126 age-and gender-matched healthy controls . Serum concentration {median (25th-75th percentiles) of IgG anti-HSP65 antibodies was substantially lower in patients with either CD (P < 0.01) or UC (P < 0.001) than in healthy controls, while no difference was found in the levels of anti-HSP60 antibodies . Low anti-HSP65 antibody levels were measured in patients with active CD and in both active and inactive UC, and only in IBD patients with no extraintestinal manifestations . In conclusion, our present findings indicate that an abnormal immune response to bacterial HSP65 or some epitopes of the protein may contribute to the dysregulation of host defenses against certain intestinal bacteria.

Environ Sci Technol, 2002 Jul 15, 36(14), 3069 - 73
Effect of starvation on the performance and re-acclimation of biotrickling filters for air pollution control; Cox HH et al.; Biotrickling filters for air pollution control are expected to encounter fluctuating conditions or periods without pollutant supply . In the present study, we investigated the effect of pollutant starvation in bench-scale biotrickling filters treating toluene . The experimental protocol consisted of starving biotrickling filters under various conditions: with or without airflow, with or without liquid recycle, and with or without an alternate carbon source (glucose) supply . The duration of the period without toluene was varied from 2 to 9 days, during time which the biotrickling filters were monitored for biomass content, endogenous and toluene-induced oxygen uptake rates during starvation, and toluene overall elimination capacity after restart . During starvation, all reactors lost their ability to degrade toluene within 5 days, regardless of the mode of starvation . The biomass content significantly decreased during starvation, in particular in those reactors where the recycle liquid was maintained, but this decrease was not critical for future re-acclimation . Glucose addition to starved biotrickling filters had several detrimental effects . It resulted in a faster decrease of the biomass content and slowed the reacclimation phase . Overall, the results show that the reacclimation of toluene-degrading biotrickling filters after periods of nonuse is short (10-24 h to re-establish full performance), and they suggest that, in the case of toluene-degrading biotrickling filters, re-acclimation time is largely governed by the induction of key pollutant-degrading enzymes.

ASAIO J, 2002 Jul-Aug, 48(4), 383 - 8
Lipopolysaccharide concentrations during superflux dialysis using unfiltered bicarbonate dialysate; van Tellingen A et al.; In the present report, the design of a new dialysate delivery system to produce low to moderately contaminated dialysate is described . In addition, the first data on bacterial counts and lipopolysaccharide (LPS) concentrations in both the dialysate and the blood during hemodialysis (HD) with superflux dialyzers are presented . In this prospective study, 37 patients were randomized into two consecutive periods of 12 weeks to HD with a high flux polysulfon (PS), a superflux PS, a superflux cellulosic tri-acetate (CTA) or a superflux CTA dialyzer with filtered dialysate (CTAf), resulting in 74 periods in which measurements were obtained . Filtered dialysate showed significantly lower bacterial counts, if compared with nonfiltered dialysate (p < 0.001) . As for LPS, marked differences were not observed between filtered and nonfiltered dialysate, whereas mean plasma LPS concentrations were below the value of the dialysate at all time points (p < 0.001) . Plasma LPS concentrations decreased significantly during HD with all four modalities (F 60: t0 0.032+/-0.005, t180 0.026+/-0.009 endotoxin units (EU)/ml, p = 0.001; F 500S, t0 0.031+/-0.004, t180 0.027+/-0.005 EU/ml, p = 0.001; Tricea 150G: t0 0.032+/-0.004, t180 0.025+/-0.005 EU/ml, p < 0.001; and Tricea 150Gf: t0 0.034+/-0.007, t180 0.025+/-0.006 EU/ml, p < 0.001) . During HD with highly permeable dialyzers and moderately contaminated dialysate, plasma LPS concentrations decreased significantly, irrespective of the material used (PS or CTA), the flux characteristics of the devices (high flux or superflux), or the presence of a bacterial filter.

Zh Mikrobiol Epidemiol Immunobiol, 2002 May-Jun, (3), 79 - 84
{Molecular biological mechanisms of the variability of Helicobacter pylori}; Domaradskii IV; Nowadays notions on the variability of Helicobacter pylori are reviewed . Genetic polymorphism of H . pylori is manifested by variability of gene properties and their order in different strains due to recombinations occurring in these bacteria much more frequently than in other bacterial species . H . pylori belongs to those bacteria which are capable of natural transformation . Transformation is very often observed both in vitro and in vivo . A significant role in the variability of H . pylori is played by transposons and specific nature of mutagenesis . The author emphasizes that differentiation between the roles played by recombinations and mutations in the variability of H . pylori is difficult . Special attention is paid to the resistance of H . pylori strains to chemotherapeutic drugs and to the mechanisms of its development.

Nucleic Acids Res, 2002 Aug 1, 30(15), 3449 - 53
BRUCE: a program for the detection of transfer-messenger RNA genes in nucleotide sequences; Laslett D et al.; A computer program, BRUCE, was developed for the identification of transfer-messenger RNA (tmRNA) genes . The program employs heuristic algorithms to search for a tRNA(Ala)-like secondary structure surrounding a short sequence encoding the tag peptide . In the 57 completely sequenced bacterial genomes where tmRNA genes have been reported previously, BRUCE identified all with no false positives . In addition, BRUCE found 99 of the 100 tmRNAs identified previously in other bacteria, red chloroplasts and cyanelles . The output of the program reports the proposed tRNA secondary structure, the tmRNA gene sequence and the tag peptide.

Mol Biol Evol, 2002 Aug, 19(8), 1341 - 9
Host-symbiont conflicts: positive selection on an outer membrane protein of parasitic but not mutualistic Rickettsiaceae; Jiggins FM et al.; The Rickettsiaceae is a family of intracellular bacterial symbionts that includes both vertically transmitted parasites that spread by manipulating the reproduction of their host (Wolbachia in arthropods) and horizontally transmitted parasites (represented by Cowdria ruminantium), and mutualists (Wolbachia pipientis in nematode worms) . We have investigated the nature of natural selection acting on an outer membrane protein, the wsp gene in Wolbachia and its homologue map1 in Cowdria, thought likely to be involved in host-parasite interactions in these bacteria . The ratio of nonsynonymous to synonymous substitution rates (d(N)/d(S)) at individual amino acid sites or at lineages within the gene's phylogeny was estimated using maximum likelihood models of codon substitution . The first hypothesis we tested was that this protein is under positive selection in the parasitic but not in the mutualistic Rickettsiaceae . This hypothesis was supported as positive selection and was detected in Cowdria and arthropod Wolbachia sequence evolution but not in the evolution of Wolbachia sequences from nematodes . Furthermore, this selection was concentrated outside the transmembrane region of the protein and, therefore, in the regions of the protein that may interact with the host . The second hypothesis tested was that positive selection would be stronger in the strains of arthropod Wolbachia that distort the host sex ratio than in those that induce cytoplasmic incompatibility . However, we found no support for this hypothesis . In conclusion, our results are consistent with the hypothesis that antagonistic coevolution causes faster evolution of surface protein sequences in parasites than in mutualists . Confirmation of this conclusion awaits the replication of these results both in additional genes and across more bacterial taxa . The regions of the wsp and map1 genes we identified as likely to be involved in host-parasite arms races should be examined in future studies of parasite virulence and host immune responses, and during the design of vaccines.

Clin Immunol, 2002 Jul, 104(1), 1 - 13
Rheumatoid factors: host resistance or autoimmunity?
Newkirk MM.
Rheumatoid factors (RFs), autoantibodies that bind to the Fc portion of IgG, are important in the immune response . RF-committed B-cells exist in the circulating lymphocyte pool in a high frequency (approximately 1-2 %) in normal individuals and in patients with pathological conditions associated with the sustained levels of circulating RF, such as rheumatoid arthritis (RA), Sjogren's syndrome (SS), and mixed cryoglobulinemia, associated with hepatitis C virus infection . RFs are induced by many infectious entities (viruses, bacteria, parasites) as a consequence of a secondary immune response to the pathogen, but usually the response is transient . It is likely that RFs play an important role in the host's defense against infection, both at the cellular level, where the RF B-cell can be an antigen presenting cell which can promote the antipathogen response, and at the humoral level, where RFs can contribute to the mopping up of the IgG antipathogen antibodies by contributing to immune complex formation and clearance . There has been much research on RFs in chronic pathological conditions, and the literature pertaining to their origin, structure, binding specificities, and possible roles in disease are discussed . The importance of the host defense, sometimes at the expense of an autoimmune response, is a balance that needs to be considered in light of a possible outcome of health or disease.

J Mol Biol, 2002 Aug 2, 321(1), 149 - 62
Crystal structure of Thermotoga maritima 4-alpha-glucanotransferase and its acarbose complex: implications for substrate specificity and catalysis; Roujeinikova A et al.; 4-alpha-Glucanotransferase (GTase) is an essential enzyme in alpha-1,4-glucan metabolism in bacteria and plants . It catalyses the transfer of maltooligosaccharides from an 1,4-alpha-D-glucan molecule to the 4-hydroxyl group of an acceptor sugar molecule . The crystal structures of Thermotoga maritima GTase and its complex with the inhibitor acarbose have been determined at 2.6A and 2.5A resolution, respectively . The GTase structure consists of three domains, an N-terminal domain with the (beta/alpha)(8) barrel topology (domain A), a 65 residue domain, domain B, inserted between strand beta3 and helix alpha6 of the barrel, and a C-terminal domain, domain C, which forms an antiparallel beta-structure . Analysis of the complex of GTase with acarbose has revealed the locations of five sugar-binding subsites (-2 to +3) in the active-site cleft lying between domain B and the C-terminal end of the (beta/alpha)(8) barrel . The structure of GTase closely resembles the family 13 glycoside hydrolases and conservation of key catalytic residues previously identified for this family is consistent with a double-displacement catalytic mechanism for this enzyme . A distinguishing feature of GTase is a pair of tryptophan residues, W131 and W218, which, upon the carbohydrate inhibitor binding, form a remarkable aromatic "clamp" that captures the sugar rings at the acceptor-binding sites +1 and +2 . Analysis of the structure of the complex shows that sugar residues occupying subsites from -2 to +2 engage in extensive interactions with the protein, whereas the +3 glucosyl residue makes relatively few contacts with the enzyme . Thus, the structure suggests that four subsites, from -2 to +2, play the dominant role in enzyme-substrate recognition, consistent with the observation that the smallest donor for T.maritima GTase is maltotetraose, the smallest chain transferred is a maltosyl unit and that the smallest residual fragment after transfer is maltose . A close similarity between the structures of GTase and oligo-1,6-glucosidase has allowed the structural features that determine differences in substrate specificity of these two enzymes to be analysed.

Mol Microbiol, 2002 Aug, 45(3), 721 - 33
Identification of a gene required for the biosynthesis of ornithine-derived lipids; Weissenmayer B et al.; Phospholipids are the membrane-forming constituents in all living organisms . In addition to phosphorus-containing lipids, the membranes of numerous bacteria contain significant amounts of phosphorus-free polar lipids, often derived from amino acids . Although lipids derived from the amino acid ornithine are widespread among bacteria, their biosynthesis is unknown . Here, we describe the isolation of mutants of Sinorhizobium meliloti deficient in the biosynthesis of ornithine-derived lipids (OL) . Complementation of such mutants with a sinorhi-zobial cosmid gene bank, subcloning of the complementing fragment and sequencing of the subclone led to the identification of a gene (olsA) coding for a presumptive acyltransferase . Amplification of this gene and its expression in OL-deficient mutant backgrounds of S . meliloti demonstrates that it is required for OL biosynthesis . An OL-deficient mutant of S . meliloti disrupted in olsA shows wild type-like growth behaviour and is capable of inducing nitrogen-fixing nodules on legume hosts . A lyso-ornithine lipid-dependent acyltransferase activity forming OL requires acyl-AcpP as the acyl donor and expression of the olsA gene.

Biochemistry (Mosc), 2002 Jul, 67(7), 778 - 85
Cell wall teichoic acids of actinomycetes of three genera of the order actinomycetales; Streshinskaya GM et al.; The structures of cell wall teichoic acids of the members of newly recognized genera of the order Actinomycetales were studied . Planotetraspora mira VKM Ac-2000T contains two types of teichoic acids: 2,3-poly(glycerol phosphate) substituted with alpha-D-Galp at C-1 of glycerol and 1,3-poly(glycerol phosphate) substituted with alpha-L-Rhap at OH-2 of glycerol (60%) . Herbidospora cretacea VKM Ac-1997T contains the chains of 1,3-poly(glycerol phosphate) partially substituted with alpha-D-Galp and alpha-D-GalpNAc at C-2 of glycerol . The majority of alpha-D-galactopyranosyl residues are substituted at OH-3 with a sulfate . The aforementioned teichoic acids have not been found in bacteria thus far . Actinocorallia herbida VKM Ac-1994T contains poly(galactosylglycerol phosphate), with the beta-Galp-(1-->2)-Gro-P repeating units being linked via the phosphodiester bonds between the OH-3 of glycerol and OH-6 of galactose . Earlier, this structure was found in the cell wall of Actinomadura madura . The polymer structures were determined by chemical analysis and using 13C-NMR spectroscopy . The results show that teichoic acids are widespread in the order Actinomycetales.

Perfusion, 2002 Jul, 17(4), 279 - 90
Whole-body hyperthermia: a review of theory, design and application; Vertree RA et al.; The intentional induction of elevated body temperature to treat malignant lesions has its origins in the 18th century . The mechanism of heat-induced cell death is not clear; however, heat induces a variety of cellular changes . For heat to exert a therapeutic effect, pathogens (bacteria, viruses, or neoplastic tissues) need to be susceptible within temperature ranges that do not exert deleterious effects on normal tissues . Hyperthermia has been used successfully to treat isolated neoplastic lesions of the head and neck, regional tumors such as melanoma of the limb, and is under investigation as either an adjunct to, or therapy for, locally disseminated and systemic diseases . The clinical utility of perfusion hyperthermia has evolved into three approaches - isolated organ or limb, tumorous invasion of a cavity, and systemic or metastatic spread . When whole-body hyperthermic treatment has been tried, it has been induced in the patient by submersion in hot wax or liquid, wrapping in plastic, encasement in a high-flow water perfusion suit, or by extracorporeal perfusion . Our group has developed an extracorporeal method, veno-venous perfusion-induced systemic hyperthermia, that was used first to safely heat swine homogenously to an average body temperature of 43 degrees C for 2 h . More recently, a Phase I clinical trial has been completed in which all patients were safely heated to 42 or 42.5 degrees C for 2 h and survived the 30-day study period . We have been sufficiently encouraged by these results and are continuing to develop this technology.

Mikrobiologiia, 2002 May-Jun, 71(3), 373 - 80
{Strain polymorphism of the plasmid profiles in Acidithiobacillus ferrooxidans}; Kondrat'eva TF et al.; Plasmid profiles were studied in 27 Acidithiobacillus ferrooxidans strains isolated from different geographic zones and substrates differing in the composition of the main sulfide minerals, and also in experimentally obtained strains with acquired enhanced resistance to the ions of heavy metals (Fe, Ni, Cu, Zn, As) . In 16 out of 20 strains isolated from different substrates, one to four 2- to 20-kb and larger plasmids were revealed . Plasmids were found in all five strains isolated from gold-containing pyrite-arsenopyrite ores and concentrates, in nine of 11 strains isolated from the ores and concentrates containing nonferrous metals, and in two of four strains isolated from the oxidation substrates of simple composition (mine waters, pyritized coals, active sludge) . Changes in the plasmid profiles in some A . ferrooxidans strains (TFZ, TFI-Fe, TFV-1-Cu) with experimentally enhanced resistance to Zn2+, Fe3+, and Cu2+, respectively, were noted as compared with the initial strains . After 30 passages on S0-containing medium, strain TFBk showed changes in the copy number of plasmids . The role of plasmids in the processes of oxidation of energy substrates and in the acquired enhanced resistance to the heavy metal ions is discussed.

Nephron, 2002 Aug, 91(4), 646 - 53
Monocyte activation in peripheral blood and dialyser eluates: phenotypic profile and cytokine release; Schouten WE et al.; BACKGROUND/AIMS: Monocyte activation and subsequent cytokine generation is presumed to be involved in haemodialysis (HD)-related morbidity . The present study was designed to investigate HD-induced changes in monocytes, with respect to their phenotypic profile and cytokine release, both in peripheral blood (PB) and dialyser eluates (DE) . In addition, the effect of the type of dialyser on monocyte activation was assessed . METHODS: Dialyser elution was performed in 8 patients after 3 h of HD, using cuprammonium (CU) and polysulfon (PS) dialysers in a randomised cross-over design . PB samples and DE were analysed for both the expression of a variety of monocyte cell surface markers (CD62L, CD11b, CD25, HLA-DR, CD64 and CD14) by flow cytometry and IL-1beta levels . Monocytes were identified by dual labelling with antibodies against CD14 . RESULTS: In PB, the expression of CD11b increased during HD with both devices, but was more pronounced with CU (CU versus PS: p < 0.05) . CD62L decreased during HD, but only significantly for PS (p < 0.02) . HLA-DR was downregulated during HD with CU (p = 0.056) . The expression of CD64 was higher during HD with CU (p = 0.02) . Finally, CD14 increased during HD with both dialysers (p < 0.03) . DE yielded a mean cell count of 51 x 10(6) cells . The proportion of monocytes in DE was 3% for CU and 4% for PS . In eluted monocytes, a significant upregulation of CD11b, CD25, and HLA-DR was observed . CD62L was downregulated when compared to PB at t(180) (p < 0.001) . In DE, no correlation was found between the type of dialyser and the phenotypic changes . In 10 of 16 DE supernatants, 6 CU and 4 PS, IL-1beta release could be demonstrated, CU yielding significantly more of this cytokine than PS (p = 0.03) . CONCLUSIONS: According to both their phenotypic profile and cytokine release, monocytes sticking to the dialyser membrane after HD are considerably more activated than circulating monocytes . Activation of eluted monocytes appeared independent of the type of dialyser, suggesting an effect of mechanical stress rather than bioincompatibility . In contrast, phenotypic activation of peripheral blood monocytes and cytokine release in the DE supernatant were mainly dialyser-dependent .

J Biol Chem, 2002 Oct 4, 277(40), 37590 - 6 Epub 2002 Jul 22.
Structure-function analysis of yeast Grx5 monothiol glutaredoxin defines essential amino acids for the function of the protein; Belli G et al.; Grx5 defines a family of yeast monothiol glutaredoxins that also includes Grx3 and Grx4 . All three proteins display significant sequence homology with proteins found from bacteria to humans . Grx5 is involved in iron/sulfur cluster assembly at the mitochondria, but the function of Grx3 and Grx4 is unknown . Three-dimensional modeling based on known dithiol glutaredoxin structures predicted a thioredoxin fold structure for Grx5 . Positionally conserved amino acids in this glutaredoxin family were replaced in Grx5, and the effect on the biological function of the protein has been tested . For all changes studied, there was a correlation between the effects on several different phenotypes: sensitivity to oxidants, constitutive protein oxidation, ability for respiratory growth, auxotrophy for a number of amino acids, and iron accumulation . Cys(60) and Gly(61) are essential for Grx5 function, whereas other single or double substitutions in the same region had no phenotypic effects . Gly(115) and Gly(116) could be important for the formation of a glutathione cleft on the Grx5 surface, in contrast to adjacent Cys(117) . Substitution of Phe(50) alters the beta-sheet in the thioredoxin fold structure and inhibits Grx5 function . None of the substitutions tested affect the structure at a significant enough level to reduce protein stability.

J Hazard Mater, 2002 Aug 5, 93(3), 339 - 52
Oxidative decontamination of chemical and biological warfare agents using L-Gel; Raber E et al.; A decontamination method has been developed using a single reagent that is effective both against chemical warfare (CW) and biological warfare (BW) agents . The new reagent, "L-Gel", consists of an aqueous solution of a mild commercial oxidizer, Oxone, together with a commercial fumed silica gelling agent, Cab-O-Sil EH-5 . L-Gel is non-toxic, environmentally friendly, relatively non-corrosive, maximizes contact time because of its thixotropic nature, clings to walls and ceilings, and does not harm carpets or painted surfaces . The new reagent also addresses the most demanding requirements for decontamination in the civilian sector, including availability, low maintenance, ease of application and deployment by a variety of dispersal mechanisms, minimal training and acceptable expense . Experiments to test the effectiveness of L-Gel were conducted at Lawrence Livermore National Laboratory and independently at four other locations . L-Gel was tested against all classes of chemical warfare agents and against various biological warfare agent surrogates, including spore-forming bacteria and non-virulent strains of real biological agents . Testing showed that L-Gel is as effective against chemical agents and biological materials, including spores, as the best military decontaminants.

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