Mol Cell, 2000 Jun, 5(6), 1059 - 65 Uracil-DNA glycosylase (UNG)-deficient mice reveal a primary role of the enzyme during DNA replication; Nilsen H et al.; Gene-targeted knockout mice have been generated lacking the major uracil-DNA glycosylase, UNG . In contrast to ung- mutants of bacteria and yeast, such mice do not exhibit a greatly increased spontaneous mutation frequency . However, there is only slow removal of uracil from misincorporated dUMP in isolated ung-/- nuclei and an elevated steady-state level of uracil in DNA in dividing ung-/- cells . A backup uracil-excising activity in tissue extracts from ung null mice, with properties indistinguishable from the mammalian SMUG1 DNA glycosylase, may account for the repair of premutagenic U:G mispairs resulting from cytosine deamination in vivo . The nuclear UNG protein has apparently evolved a specialized role in mammalian cells counteracting U:A base pairs formed by use of dUTP during DNA synthesis. Photochem Photobiol, 2000 Jul, 72(1), 62 - 74 Damage to DNA in bacterioplankton: a model of damage by ultraviolet radiation and its repair as influenced by vertical mixing; Huot Y et al.; A model of UV-induced DNA damage in oceanic bacterioplankton was developed and tested against previously published and novel measurements of cyclobutane pyrimidine dimers (CPD) in surface layers of the ocean . The model describes the effects of solar irradiance, wind-forced mixing of bacterioplankton and optical properties of the water on net DNA damage in the water column . The biological part includes the induction of CPD by UV radiation and repair of this damage through photoreactivation and excision . The modeled damage is compared with measured variability of CPD in the ocean: diel variation in natural bacterioplankton communities at the surface and in vertical profiles under different wind conditions (net damage as influenced by repair and mixing); in situ incubation of natural assemblages of bacterioplankton (damage and repair, no mixing); and in situ incubation of DNA solutions (no repair, no mixing) . The model predictions are generally consistent with the measurements, showing similar patterns with depth, time and wind speed . A sensitivity analysis assesses the effect on net DNA damage of varying ozone thickness, colored dissolved organic matter concentration, chlorophyll concentration, wind speed and mixed layer depth . Ozone thickness and mixed layer depth are the most important factors affecting net DNA damage in the mixed layer . From the model, the total amplification factor (TAF; a relative measure of the increase of damage associated with a decrease in ozone thickness) for net DNA damage in the euphotic zone is 1.7, as compared with 2.1-2.2 for irradiance weighted for damage to DNA at the surface. Med Sci Sports Exerc, 2000 Jul, 32(7 Suppl), S377 - 88 Glutamine and arginine: immunonutrients for improved health; Field CJ et al.; There is considerable literature demonstrating that specific nutrients can influence immune function in health and disease . This review will examine the literature and the rational for classifying two amino acids, glutamine (gln) and arginine (arg), as "immunonutrients" during infections . An understanding of immune defenses during infections (virus, parasite, bacteria, protozoa) and metabolism of gln and arg by immune cells is necessary to understand how these nutrients can influence specific functions of the immune system . This review focuses on several key clinical studies in immunosuppressed individuals (burn patients, individuals with cancer and HIV infection, and those undergoing surgery or who have experienced major traumas) that have tested the hypothesis that the provision of gln and/or arg is beneficial to immune function and clinical outcome . These clinical studies support the dietary "essentiality" of these two nutrients for improving immune responses in most immunosuppressive states associated with high rates of infection . However, the role of these nutrients in modulating the immune changes that occur with exercise in healthy athletes demands additional experiments. Curr Opin Rheumatol, 2000 Jul, 12(4), 274 - 80 Psoriatic arthritis: evolving concepts; Scarpa R et al.; Articles included in this review reflect the recent advances made in basic research and the clinical management of psoriatic arthritis in 1999 . Some of these advances are destined to modify the current approach to the disease . The problems related to nosology and epidemiology, the two still controversial aspects, are discussed first . Genetic susceptibility to psoriasis and psoriatic arthritis, and the inciting role played by some bacteria, are confirmed, and attention is focused on the role of T cells, cytokines, adhesion molecules, and angiogenetic factors in the skin and synovial membrane . New classification criteria are provided and a simplified spectrum of the disease seems to emerge from clinical studies . Modern imaging techniques enable early articular changes to be discovered, support innovative pathogenetic hypotheses, and allow new therapeutic approaches. Curr Opin Rheumatol, 2000 Jul, 12(4), 263 - 8 Clinical aspects, outcome assessment, and management of ankylosing spondylitis and postenteric reactive arthritis; van der Linden S et al.; The cause of ankylosing spondylitis remains unclear . Proof that this disorder is an autoimmune disease attributable to crossreactivity between bacteria and HLA-B27 is still lacking . Differences in endogenous peptide presentation by HLA-B27 subtypes might be relevant in the etiopathogenesis . Fractures of the osteoporotic spine contribute to morbidity . Spinal cord injury may occur . MR imaging enables identifying sacroiliitis earlier than plain radiography . Sweet syndrome has now been described in patients with ankylosing spondylitis and Crohn disease . Progress has been made in the assessment of ankylosing spondylitis . There are now core sets for different settings and validated instruments for functioning and disease activity that will enable demonstrating efficacy of new therapeutic interventions.The debate continues on classification of postinfectious and reactive arthritis . Bacterial antigens may be found in the inflamed joints; occasionally 16S ribosomal RNA is also demonstrated . Antibiotics seem not to be effective in postenteric reactive arthritis.More than 25 years have now elapsed since the association between ankylosing spondylitis and HLA-B27 was first described in 1973 . The cause of this disease is still unknown, but a lot of progress has been made regarding the molecular structure of HLA-B27, the spectrum of disease, the clinical and radiographic assessment of ankylosing spondylitis, and its treatment . Recent advances in research on ankylosing spondylitis are reviewed here. Comp Biochem Physiol A Mol Integr Physiol, 2000 May, 126(1), 33 - 44 Symbiosis-enhanced gene expression in cnidarian-algal associations: cloning and characterization of a cDNA, sym32, encoding a possible cell adhesion protein; Reynolds WS et al.; Mutualistic endosymbioses between two partners are complex associations that are regulated by the genetic interactions of the partners . One important marine symbiosis is that between various cnidarians, such as corals and anemones, and their photosynthetic algal symbionts . We have been interested in characterizing cnidarian host genes that are expressed as a function of the symbiotic state, using the temperate sea anemone Anthopleura elegantissima as a model . In this study, we report on symbiosis-enhanced expression and synthesis of sym32 in anemones . We characterized the full-length sym32 cDNA, obtained by RT-PCR, and demonstrated, by semi-quantitative RT-PCR, that sym32 transcript was much more abundant in symbiotic than in non-symbiotic host anemone RNA . Further, using immunoblots, we determined that an antibody made to a sym32 fusion protein labeled a 32 kD band much more strongly in symbiotic compared to non-symbiotic anemone protein homogenates . Databank searches revealed that the sym32 deduced amino acid sequence shares significant homology with the fasciclin I (Fas I) family of homophilic cell adhesion proteins, present in a variety of organisms ranging from bacteria to humans . This strong homology with the Fas I family suggests that sym32 is involved in regulation of the symbiosis by mediating cell-cell interactions. Comp Biochem Physiol A Mol Integr Physiol, 2000 May, 126(1), 1 - 16 Reproductive characteristics and strategies of reducing-system bivalves; Le Pennec M et al.; The reproductive biology of Type 3 reducing-system bivalves (those whose pallial cavity is irrigated with water rich in reducing substances) is reviewed, with respect to size-at-maturity, sexuality, reproductive cycle, gamete size, symbiont transmission, and larval development/dispersal strategies . The pattern which emerges from the fragmentary data is that these organisms present reproductive particularities associated with their habitat, and with their degree of reliance on bacterial endosymbionts . A partial exception to this pattern is the genus Bathymodiolus, which also presents fewer trophic adaptations to the reducing environment, suggesting a bivalent adaptive strategy . A more complete understanding of the reproductive biology of Type 3 bivalves requires much more data, which may not be feasible for some aspects in the deep-sea species. Mol Biol Evol, 2000 Aug, 17(8), 1232 - 9 Relationship between the occurrence of cysteine in proteins and the complexity of organisms; Miseta A et al.; The occurrence and relative positions of cysteine residues were investigated in proteins of various species . Considering random mathematical occurrence for an amino acid coded by two codons (3 . 28%), cysteine is underrepresented in all organisms investigated . Representation of cysteine appears to correlate positively with the complexity of the organism, ranging between 2.26% in mammals and 0 . 5% in some members of the Archeabacteria order . This observation, together with the results obtained from comparison of cysteine content of various ribosomal proteins, indicates that evolution takes advantage of increased use of cysteine residues . In all organisms studied except plants, two cysteines are frequently found two amino acid residues apart (C-(X)(2)-C motif) . Such a motif is known to be present in a variety of metal-binding proteins and oxidoreductases . Remarkably, more than 21% of all of cysteines were found within the C-(X)(2)-C motifs in ARCHEA.: This observation may indicate that cysteine appeared in ancient metal-binding proteins first and was introduced into other proteins later. Chronobiol Int, 2000 Jul, 17(4), 433 - 51 Circadian clocks: what makes them tick? Zordan M, Costa R, Macino G, Fukuhara C, Tosini G. In the not too distant past, it was common belief that rhythms in the physical environment were the driving force, to which organisms responded passively, for the observed daily rhythms in measurable physiological and behavioral variables . The demonstration that this was not the case, but that both plants and animals possess accurate endogenous time-measuring machinery (i.e., circadian clocks) contributed to heightening interest in the study of circadian biological rhythms . In the last few decades, flourishing studies have demonstrated that most organisms have at least one internal circadian timekeeping device that oscillates with a period close to that of the astronomical day (i.e., 24h) . To date, many of the physiological mechanisms underlying the control of circadian rhythmicity have been described, while the improvement of molecular biology techniques has permitted extraordinary advancements in our knowledge of the molecular components involved in the machinery underlying the functioning of circadian clocks in many different organisms, man included . In this review, we attempt to summarize our current understanding of the genetic and molecular biology of circadian clocks in cyanobacteria, fungi, insects, and mammals. Yale J Biol Med, 1999 Jul-Aug, 72(4), 281 - 5 Antifungal resistance in yeast vaginitis; Dun E; The increased number of vaginal yeast infections in the past few years has been a disturbing trend, and the scientific community has been searching for its etiology . Several theories have been put forth to explain the apparent increase . First, the recent widespread availability of low-dosage, azole-based over-the-counter antifungal medications for vaginal yeast infections encourages women to self-diagnose and treat, and women may be misdiagnosing themselves . Their vaginitis may be caused by bacteria, parasites or may be a symptom of another underlying health condition . As a result, they may be unnecessarily and chronically expose themselves to antifungal medications and encourage fungal resistance . Second, medical technology has increased the life span of seriously immune compromised individuals, yet these individuals are frequently plagued by opportunistic fungal infections . Long-term and intense azole-based antifungal treatment has been linked to an increase in resistant Candida and non-Candida species . Thus, the future of limiting antifungal resistance lies in identifying the factors promoting resistance and implementing policies to prevent it. EXS, 1999, 87, 201 - 9 Inhibitors of chitinases; Spindler KD et al.; In this review we describe inhibition of chitinases from bacteria, fungi, plants and animals by allosamidin and its derivatives, cyclic peptides, styloguanidin and divalent cations . Most information is available for allosamidin, whose important structural features necessary for inhibition are known . At least one N-acetylallosamine sugar must be present, and the spatial arrangement of the allosamizoline moiety are important for inhibition . Less complex compounds are therefore possible as lead structures for the development of agents interfering with chitinase . There is a pronounced species specificity in chitinase inhibition by allosamidin: half-maximal values are often in the range of 0.1-1 microM (e.g . in all arthropods), being lower in nematodes (0.048, 0.0002 microM, respectively) and amoeba (0.002-0.01 microM) and quite divergent in fungi (0.01-70 microM) . These differences cannot be caused by the catalytic centers of family 18 and 19 chitinases. EXS, 1999, 87, 137 - 56 Classification of chitinases modules; Henrissat B; Chitinases frequently display a modular structure featuring a catalytic domain attached to one or several ancillary noncatalytic domains whose function is often chitin binding . Gene cloning and DNA sequencing have allowed the determination of a massive number of amino acid sequences of chitinases during the last 10 years . This chapter presents a unifying classification system of the various chitinase modules that combines specific features of their sequences, three-dimensional structures and reaction mechanisms. EXS, 1999, 87, 125 - 35 The structure and action of chitinases; Robertus JD et al.; Chitin is second only to cellulose in biomass and it is an important component of many cell wall structures . Several families of enzymes, of distinctly different structure, have evolved to hydrolyze this important polysaccaride . Glycohydrolase family 18 enzymes, chitinases, are characterized by an eight-fold alpha/beta barrel structure; it has representatives among bacteria, fungi, and higher plants . In general these chitinases act through a retaining mechanism in which beta linked polymer is cleaved to release a beta anomer product . Family 19 chitinases are found primarily in plants but some are found in bacteria . Members of this family are related to one another by amino acid sequence, but are unrelated to family 18 proteins . They have a bilobal structure with a high alpha-helical content . Despite any significant sequence homology with lysozymes, structural analysis reveals that family 19 chitinases, together with family 46 chitosanases, are similar to several lysozymes including those from T4-phage and from goose . The structures reveal that the different enzyme groups arose from a common ancestor glycohydrolase antecedent to the procaryotic/eucaryotic divergence . In general, the family 19 enzymes operate through an inverting mechanism. EXS, 1999, 87, 111 - 23 Biochemistry of chitinases; Koga D et al.; Chitinases are found in many organisms, and their properties seem to be closely related to their biological function . In this chapter, the physicochemical properties of chitinases such as molecular size are compared among organisms, and the optimum and stability conditions for chitinase activity are described . Furthermore, considering their classification based on amino acid sequence, kinetic behaviors are discussed together with their biological functions . In particular, hydrolytic mechanisms such as inversion and retention of the substrate are discussed in relation to allosamidin inhibition. J Cell Biochem, 2000 Jul 19, 79(1), 139 - 49 Mediation of cell-substratum adhesion by RasG in Dictyostelium; Chen CF et al.; Previous studies on the functions of the RasG gene in the cellular slime mold, Dictyostelium discoideum, have revealed that it is required for normal motility and cytokinesis . To further understand how the RasG gene regulates various cellular processes, we transformed an activated form of RasG, that is, RasG (G12T), a mutation from glycine to threonine at amino acid position 12 into wild type KAX-3 cells . This produced moderate but constitutive RasG(G12T) protein expression, which causes cells to become significantly more adherent to the substratum than are wild type cells . The RasG(G12T) transformants also grow slowly on bacterial plates, and engulf fewer bacteria on filter surfaces, indicating a defect in phagocytosis when cells are adhered . The expression of the activated RasG also dramatically reduces the number of filopodia on the cell surface . Tyrosine phosphorylation on a 43 kDa protein (most likely actin) of the RasG (G12T) transformants is highly elevated . Taken together, our observations suggest that RasG is crucial for Dictyostelium cell-substratum adhesion during growth and that RasG may play a role in adhesion-mediated phagocytosis . Our results also suggest that RasG is important in filopodial formation and that RasG is involved in the signal pathway that is regulated by tyrosine phosphorylation . Mech Dev, 2000 Jul, 95(1-2), 301 - 4 The insect immune protein hemolin is expressed during oogenesis and embryogenesis; Bettencourt R et al.; Hemolin is the most abundant bacteria-induced proteins in Hyalophora cecropia hemolymph . Its structural features, both at the protein and gene level, ascribe this molecule to the immunoglobulin gene superfamily (IgSF) with particular homology to neural cell adhesion molecules . An increasing number of evidence suggest a role in immune recognition and in cell adhesion events . Hemolin is also developmentally regulated as suggested by changes in its concentration during larval and pupal ecdysis (Trenczek, T., 1998 . Endogenous defense mechanisms of insects . Zoology 101, 298-315; Lanz-Mendoza, H., Faye, I., 1999 . Physiological aspects of the immunoglobulin superfamily in invertebrates . Dev . Comp . Immunol . 23, 359-374) . In the present study the expression of hemolin was investigated in oogenesis and in early embryogenesis . Our results reveal that hemolin is expressed in follicles and in epidermal and neural tissues of embryos. Anal Biochem, 2000 Aug 1, 283(2), 222 - 7 Synthesis of {(32)P}phosphoramidate for use as a low molecular weight phosphodonor reagent; Buckler DR et al.; Phosphoramidate serves as a useful phosphodonor reagent in protein and peptide phosphorylation, notably in studying two-component signal transduction systems in which low molecular weight phosphodonors can substitute for the phosphodonor function of histidine protein kinases in in vitro phosphorylation studies of response regulator proteins . A convenient method for the synthesis of radiolabeled phosphoramidate has not been developed, and this has limited its broader use . Here we report the synthesis of radiolabeled ammonium hydrogen phosphoramidate {(NH(4))H(32)PO(3)NH(2)} which is achieved by activation of {(32)P}orthophosphate with ethyl isocyanate followed by aminolysis with ammonium hydroxide to form the desired phosphoramidate . The procedure is conveniently carried out in a microfuge tube and requires only two successive precipitation steps to obtain pure ammonium hydrogen phosphoramidate . Molar yields of 15-30% and specific activities of 10-20 Ci/mol are readily achieved . Phosphorylation of microgram quantities of response regulator proteins CheY, CheB, and DrrA is shown . Low level, but detectable, nonspecific phosphorylation was observed for reactions near ambient temperatures when substrate response regulators lacking the active site aspartate but containing histidine residues are used . More significant levels of nonspecific phosphorylation were observed for reactions at elevated temperatures when using a nonresponse regulator control protein (RNase A) . In Vivo, 2000 May-Jun, 14(3), 463 - 6 Preventive effects of sulphasalazine on colorectal carcinogenesis in mice with ulcerative colitis; Suzuki S et al.; Sulphasalazine has been used in the treatment of ulcerative colitis and is known to be a prodrug and split into sulphapyridine and 5-aminosalicylic acid by bacteria in the colon . An increased incidence of colorectal carcinoma is known to occur in patients with ulcerative colitis, which displays a recurrence-remission cycle on colorectal mucosa, i.e., the ulceration and regeneration periods of the colorectal mucosa . Repeated mucosal necrosis-regeneration sequence in chronic ulcerative colitis induced with 3% dextran sulfate sodium led to colorectal carcinogenesis in azoxymethane-pretreated mice . Additive treatment with sulphasalazine normalized the enlarged organs, i.e . liver, spleen and kidney and anemia and leucocytosis induced with 3% dextran sulfate sodium resulted in the reduction of tumorous regions with high-grade dysplasia. J Mol Biol, 2000 Jul 28, 300(5), 1079 - 99 Multiple regulators and their interactions in vivo and in vitro with the cbb regulons of Rhodobacter capsulatus; Vichivanives P et al.; The cbb(I) and cbb(II) operons encode structural genes which are important for carbon dioxide fixation via the Calvin-Benson-Bassham reductive pentose phosphate pathway in Rhodobacter capsulatus . Each operon is regulated by cognate LysR-type transcriptional activators, CbbR(I) and CbbR(II), with the product of the cbbR(I) gene, CbbR(I), able to control its own transcription under some growth conditions . Furthermore, CbbR(I) may at least partially regulate the cbb(II) operon, with significant, yet regulated transcription of the cbb(II) operon occurring in the absence of any CbbR . These results suggested the importance of additional regulators . Thus, in addition to the rather specific control exerted by CbbR, a more globally significant regulatory system, the RegA-RegB (PrrA-PrrB) two-component system, was found to contribute to transcriptional regulation of each cbb operon . The regA and regB mutant strains were found to contain constitutive levels of form I and form II RubisCO, the major proteins encoded by the cbb(I) and cbb(II) operons, respectively . In addition, DNaseI footprint analyses indicated that RegA*, a constitutively active mutant form of RegA, binds specifically to cbb(I) and cbb(II) promoter-operator regions . CbbR(I), CbbR(II), and RegA binding loci were localized relative to transcription start sites, leading to a coherent picture of how each of these regulators interacts with specific promoter-operator sequences of the cbb operons . Ecotoxicol Environ Saf, 2000 Jul, 46(3), 342 - 50 Toxicity of Euphorbia milii latex and niclosamide to snails and nontarget aquatic species; Oliveira-Filho EC et al.; The toxicity of Euphorbia milii molluscicidal latex and niclosamide (NCL) to target snails (Biomphalaria glabrata and Biomphalaria tenagophila) and nontarget aquatic organisms is evaluated . Planorbidae snails were killed by very low concentrations of lyophilized latex (48-h LC(50), mg/L: B . glabrata, 0.12; B . tenagophila, 0.09; Helisoma duryi, 0.10) . Latex was less toxic (48-h LC(50) or EC(50), mg/L) to oligochaeta (Tubifex tubifex, 0.31), planktonic crustacea (Daphnia similis, 0.38; C . dubia, 1.07; Artemia sp., 0.93), and fishes (Danio rerio, 0.96; Poecilia reticulata, 1 . 39), and considerably less toxic to Ampullariidae snails (Pomacea sp . , 10.55) and frog tadpoles (Rana catesbeiana, 7.50) . Latex (up to 100 mg/L) was not toxic to bacteria (P . putida and V . fischeri), algae (Selenastrum capricornutum and Chlorella vulgaris), and mosquito larvae (Anopheles albitarsis, Aedes aegypti, Aedes fluviatilis) . NCL was very toxic (48-h LC(50) or EC(50), mg/L) to Planorbidae snails (B . glabrata, 0.15, B . tenagophila, 0.13; H . duryi, 0.10), T . tubifex (0.11), crustacea (D . similis, 0.19; Ceriodaphnia dubia, 0.47; Artemia sp . 0.18), fishes (D . rerio, 0.25; P . reticulata, 0.29), R . catesbeiana (0.16), and Pomacea sp . (0.76) . NCL was toxic to bacteria, algae (96-h IC(50), mg/L: S . capricornutum, 0.34; C . vulgaris, 1.23) and slightly toxic to mosquito larvae . In conclusion, E . milii latex, as compared with the reference molluscicide niclosamide, presents a higher degree of selectivity toward snails which are intermediate hosts of Schistosoma trematodes . Gene, 2000 Jul 11, 252(1-2), 61 - 9 Fructose utilization and pathogenicity of Spiroplasma citri: characterization of the fructose operon; Gaurivaud P et al.; Transposon Tn4001 mutagenesis of Spiroplasma citri wild-type (wt) strain GII-3 led to the isolation and characterization of non-phytopathogenic mutant GMT 553 . In this mutant, transposon Tn4001 is inserted within the first gene of the fructose operon . This operon comprises three genes . The first gene (fruR) codes for a putative transcriptional regulator protein belonging to the deoxyribonucleoside repressor (DeoR) family . Sequence similarities and functional complementation of mutant GMT 553 with different combinations of the wt genes of the fructose operon showed that the second gene (fruA) codes for the permease of the phosphoenolpyruvate:fructose phosphotransferase system (fructose PTS), and the third, fruK, for the 1-phosphofructokinase (1-PFK) . Transcription of the fructose operon in wt strain GII-3 resulted in two messenger RNAs, one of 2.8kb and one of 3.8kb . Insertion of Tn4001 in the genome of mutant GMT 553 abolished transcription of the fructose operon, and resulted in the inability of this mutant to use fructose . Functional complementation experiments demonstrated that fructose utilization was restored with fruR-fruA-fruK, fruA-fruK or fruA only, but not with fruR or fruR-fruA . This is the first time that an operon for sugar utilization has been functionally characterized in the mollicutes. J Biol Chem, 2000 Oct 27, 275(43), 33782 - 90 Both RadA and RadB are involved in homologous recombination in Pyrococcus furiosus; Komori K et al.; RecA and Rad51 proteins are essential for homologous recombination in Bacteria and Eukarya, respectively . Homologous proteins, called RadA, have been described for Archaea . Here we present the characterization of two RecA/Rad51 family proteins, RadA and RadB, from Pyrococcus furiosus . The radA and radB genes were not induced by DNA damage resulting from exposure of the cells to gamma and UV irradiation and heat shock, suggesting that they might be constitutively expressed in this hyperthermophile . RadA had DNA-dependent ATPase, D-loop formation, and strand exchange activities . In contrast, RadB had a very weak ATPase activity that is not stimulated by DNA . This protein had a strong binding affinity for DNA, but little strand exchange activity could be detected . A direct interaction between RadA and RadB was detected by an immunoprecipitation assay . Moreover, RadB, but not RadA, coprecipitated with Hjc, a Holliday junction resolvase found in P . furiosus, in the absence of ATP . This interaction was suppressed in the presence of ATP . The Holliday junction cleavage activity of Hjc was inhibited by RadB in the absence, but not in the presence, of ATP . These results suggest that RadB has important roles in homologous recombination in Archaea and may regulate the cleavage reactions of the branch-structured DNA. J Exp Biol, 2000 Aug, 203(Pt 16), 2503 - 9 Wolbachia infection and cytoplasmic incompatibility in the cricket Teleogryllus taiwanemma; Kamoda S et al.; Wolbachia are cytoplasmically inherited bacteria found in many arthropods . They induce various reproductive alterations in their hosts, including cytoplasmic incompatibility, thelytokous parthenogenesis, feminization and male-killing . In this study, we examined Wolbachia infection and its effects on the host cricket Teleogryllus taiwanemma . In a phylogenetic study based on the wsp gene coding for a Wolbachia surface protein, the Wolbachia strain harboured by T . taiwanemma was clustered together with those harboured by Laodelphax striatellus, Tribolium confusum, Acraea encedon, Trichogramma deion and Adalia bipunctata . Crossing experiments using the Wolbachia-infected and uninfected strains of cricket showed that the infection is associated with the expression of unidirectional cytoplasmic incompatibility: the egg hatch rate in the incompatible cross between the infected males and uninfected females was 20.3 % . We also examined the distribution of Wolbachia within the host using polymerase chain reaction assays; they were detected in the antennae, heads, forewings, hindwings, testes, ovaries, Malpighian tubules, foot muscles and fat bodies . Quantitative polymerase chain reaction assays showed that the bacterial density was highest in the fat bodies, followed by the ovaries and testes . Wolbachia were not detected in the haemolymph or in mature spermatozoa . The spermatozoa of the infected male may be modified by the presence of Wolbachia during its development . To examine this possibility, we compared the profiles of sperm proteins between the infected and uninfected males using two-dimensional gel electrophoresis . However, no differences in the protein profiles were observed. IUBMB Life, 2000 May, 49(5), 365 - 73 Mitochondria in the programmed death phenomena; a principle of biology: "it is better to die than to be wrong"; Skulachev VP; The very fact that mitochondria participate in amplification of the cell suicide signals has stimulated interest in the mechanism of this and related phenomena . It seems probable that mitochondria possess an autonomic system that allows them to commit suicide . This mitoptosis is mediated by reactive oxygen species (ROS), causing opening of the permeability transition pores (PTP) in the inner mitochondrial membrane . Mitoptosis can purify the mitochondrial population in a cell from the ROS-overproducing organelles . Massive mitoptosis can result in apoptosis (programmed cell death) because of the release of proapoptotic proteins from the mitochondrial intermembrane space, a mechanism purifying tissues from the ROS-overproducing and other unwanted cells . Large-scale apoptosis can be used by organisms to eliminate some organs during ontogenesis (organoptosis) . In adult organisms, organoptosis of organs of vital importance may entail a programmed death of individuals (phenoptosis) . This mechanism might purify kins, communities, and populations from individuals becoming dangerous because of, for example, heavy infection (septic shock) . It is hypothesized that aging represents a slow ROS-linked phenoptosis that eliminates individuals with damaged genomes and gives reproductive advantage to those who succeeded in a better preservation of their genomes from damage. J Air Waste Manag Assoc, 2000 Jun, 50(6), 954 - 60 A sorptive slurry bioscrubber for the control of acetone; Hammervold RE et al.; A sorptive slurry bioscrubber adds powdered activated carbon (PAC) to a conventional suspended-growth bioscrubber . The activated carbon increases pollutant removal from the gas phase due to adsorption on carbon . The carbon is bioregenerated in the oxidation reactor and recycled to the scrubbing column . A three-stage, conventional bioscrubber was tested with and without carbon . The experiments showed that the PAC improved the removal efficiency of the system and that bioregeneration occurred . At an inlet gas-phase acetone concentration of 50 ppmv, the steady-state removal increased from 88 to 95% when activated carbon was added to the biological slurry. J Cardiovasc Surg (Torino), 2000 Apr, 41(2), 311 - 5 Management of infected peripheral bypass by selective partial graft removal and arterial homograft insertion . Two case reports; Locati P et al.; We present two cases of partial graft removal and cryopreserved arterial homograft insertion for treatment of patent axillobifemoral (AXB) polytetrafluoroethylene (PTFE) prosthesis with infection confined only to a part of the graft . In the first patient, infection was confined to the left inguinal site; in the second, there was a cutaneous fistula in the middle prosthetic thoracic tract . Neither patient presented signs of systemic sepsis and radio immunological tests were positive only in a confined tract . After surgery, both patients showed early recovery and currently (mean follow-up 21-month) they are disease-free . Selective partial graft removal appears to give satisfactory results and may reduce the risk of complications compared with total graft removal Moreover, arterial homograft shows greater resistance to infection compared to alloplastic materials, when autologous veins are not available and/or not suitable. Rev Clin Esp, 2000 May, 200(5), 245 - 51 {Infection after orthotopic liver transplantation: analysis of the first 120 consecutive cases}; Montejo M et al.; OBJECTIVE: To report the infectious complications and presentation time of the first 120 consecutive liver transplants performed at our institution . METHODS: Prospective study of infectious complications among 120 consecutive adult patients who received orthotopic liver transplantation at Hospital de Cruces, from February 1996 to November 1998 . Two patients received a renal transplant concomitantly . The same surveillance protocols were used for all patients and the criteria used to define infections were those reported by other authors . RESULTS: The group consisted of 120 patients, 95 males and 25 females . The age ranged from 20 and 66 years (mean: 54 +/- 9 years) . The indications for transplantation included alcoholic cirrhosis (47%), HCV cirrhosis (20%), hepatocellular carcinoma (17.5%), fulminant hepatitis (6%), primary biliary cirrhosis (2.5%) and miscellaneous conditions (7%) . Three patients required retransplantation . Acute rejection was histologically diagnosed in 38 patients (31%) . None of the patients had corticosteroid-resistant rejection . Fifty-one patients (42.5%) developed 76 episodes of severe infection, which included: 48 episodes of bacterial infection among 33 patients (27.5%), tuberculosis in 7 patients (6%), 9 episodes of fungal infection among 8 patients (7%) and cytomegalovirus (CMV) infection among 8.5% of patients . No patient developed Pneumocystis carinii pneumonia . Fifteen (12.5%) patients died: six (12.5%) with active infection, and in four of them the infection was considered the cause of death . CONCLUSIONS: Infection rates due to bacteria and fungi were similar to those reported in the literature . A high rate of tuberculosis was found, which possible correlated with the high incidence of this disease in the general population . The low incidence of CMV infection was probably due to the preemptive therapy with gancyclovir . Trimethoprim-sulfamethoxazol prophylaxis against Pneumocystis carinii was highly effective. Gig Sanit, 2000 May-Jun, (3), 31 - 4 {Epidemiological hazards of low-temperature food storage}; Buzoleva LS et al.; Refrigerator food storage lose its preventive value . This is particularly associated with the specific features of the pathogens of saprozoonosis which can easily adapt to low temperatures and feed deficit . Pseudotuberculosis agents were used to show that saprozoonosis pathogens can live and feed in a warm-blood being and in the environment . Their biological features require new approaches to controlling these infections. Mol Carcinog, 2000 Jun, 28(2), 63 - 9 The proprotein convertases furin and PACE4 play a significant role in tumor progression; Bassi DE et al.; Processing of latent precursor proteins by proprotein convertases (PCs) into their biologically active products is a common mechanism required for many important biologic functions . This process is tightly regulated, leading to the generation of active peptides and proteins including neuropeptides and polypeptide hormones, protein tyrosine phosphatases, growth factors and their receptors, and enzymes including matrix metalloproteases (MMPs) . These processing reactions occurs at pairs of basic amino acids . Within the past several years, a novel family of Ca(2+)-dependent serine proteases has been identified, all of which possess homology to the endoproteases subtilisin (bacteria) and kexin (yeast) . This family of PCs is currently comprised of fewer than a dozen members, known as furin/paired basic amino-acid-cleaving enzyme (PACE), PC1/PC3, PC2, PC4, PACE4, PC5/PC6, and PC7/PC8/lymphoma proprotein convertase . They share a high degree of amino-acid identity of 50-75% within their catalytic domains . Despite the relatively high degree of homology in the PC family, only PACE4 and furin localize to the same chromosome: mouse chromosome 7 and human chromosome 15 . Recent reports have supported a possible functional role for PCs in tumorigenesis . For instance, convertases have been shown to be expressed in various tumor lines and human primary tumors . Furin and PACE4 process stromelysin 3 (MMP-11 or Str-3), an MMP involved in tumor invasion, into its mature, active form . Similarly, a growing family of MMPs, known as membrane-type metalloproteinases (MT-MMPs), and growth factors and adhesion molecules such as E-cadherin show similar amino-acid motifs and thus could be activated by furin and PACE4 . These data, taken together with the high expression levels of PACE4 in 50% of murine chemically induced spindle cell tumors, confer to PACE4 and possibly other PCs a possible functional role in the activation of MMPs and consequently in tumor cell invasion and tumor progression . This was further supported by the remarkable enhancement in the invasive ability of the PACE4-transfected murine tumor cell lines . Mol . Carcinog . 28:63-69, 2000 . Yeast, 2000 Jun 30, 17(2), 111 - 23 Comparative genomics uncovers large tandem chromosomal duplications in Mycobacterium bovis BCG Pasteur; Brosch R et al.; On direct comparison of minimal sets of ordered clones from bacterial artificial chromosome (BAC) libraries representing the complete genomes of Mycobacterium tuberculosis H37Rv and the vaccine strain, Mycobacterium bovis BCG Pasteur, two major rearrangements were identified in the genome of M . bovis BCG Pasteur . These were shown to correspond to two tandem duplications, DU1 and DU2, of 29 668 bp and 36 161 bp, respectively . While DU1 resulted from a single duplication event, DU2 apparently arose from duplication of a 100 kb genomic segment that subsequently incurred an internal deletion of 64 kb . Several lines of evidence suggest that DU2 may continue to expand, since two copies were detected in a subpopulation of BCG Pasteur cells . BCG strains harbouring DU1 and DU2 are diploid for at least 58 genes and contain two copies of oriC, the chromosomal origin of replication . These findings indicate that these genomic regions of the BCG genome are still dynamic . Although the role of DU1 and DU2 in the attenuation and/or altered immunogenicity of BCG is yet unknown, knowledge of their existence will facilitate quality control of BCG vaccine lots and may help in monitoring the efficacy of the world's most widely used vaccine . Proteins, 2000 Sep 1, 40(4), 590 - 612 Adrenodoxin: structure, stability, and electron transfer properties; Grinberg AV et al.; Adrenodoxin is an iron-sulfur protein that belongs to the broad family of the {2Fe-2S}-type ferredoxins found in plants, animals and bacteria . Its primary function as a soluble electron carrier between the NADPH-dependent adrenodoxin reductase and several cytochromes P450 makes it an irreplaceable component of the steroid hormones biosynthesis in the adrenal mitochondria of vertebrates . This review intends to summarize current knowledge about structure, function, and biochemical behavior of this electron transferring protein . We discuss the recently solved first crystal structure of the vertebrate-type ferredoxin, the truncated adrenodoxin Adx(4-108), that offers the unique opportunity for better understanding of the structure-function relationships and stabilization of this protein, as well as of the molecular architecture of {2Fe-2S} ferredoxins in general . The aim of this review is also to discuss molecular requirements for the formation of the electron transfer complex . Essential comparison between bacterial putidaredoxin and mammalian adrenodoxin will be provided . These proteins have similar tertiary structure, but show remarkable specificity for interactions only with their own cognate cytochrome P450 . The discussion will be largely centered on the protein-protein recognition and kinetics of adrenodoxin dependent reactions. Thorax, 2000 Aug, 55(8), 678 - 84 Distinct effects of Broncho-Vaxom (OM-85 BV) on gp130 binding cytokines; Roth M et al.; BACKGROUND: Broncho-Vaxom (OM-85 BV) is known to support respiratory tract resistance to bacterial infections . In vivo and in vitro studies in animals and humans have shown that the action of the drug is based on the modulation of the host immune response, and it has been found to upregulate interferon gamma (IFN-gamma) and interleukin (IL)-2, IL-6, and IL-8 . These immunomodulatory effects of the compound may explain its stimulation on T helper cells and natural killer cells . Following earlier findings that OM-85 BV induces the synthesis of IL-6, a study was undertaken to investigate its possible effect on other gp130 binding cytokines including IL-11, IL-12, leukaemia inhibitory factor (LIF), oncostatin M (OSM), and ciliary neutrophil factor (CNTF) . Its modulation of the corresponding receptors of the above mentioned cytokines and of the signal transducer gp130 in human pulmonary fibroblasts and peripheral blood lymphocytes was also studied . METHODS: Transcription of cytokines was assessed by Northern blot analysis . Secretion of cytokines was analysed using commercially available enzyme linked immunosorbent assay kits . Cytokine receptors and gp130 proteins were determined by Western blot analysis . RESULTS: OM-85 BV increased the expression of IL-11 in human lung fibroblasts, but not in lymphocytes, in a dose and time dependent manner by maximal fivefold within 20 hours . The compound inhibited serum induced IL-12 expression in peripheral blood lymphocytes but did not induce OSM, LIF, or CNTF at any concentration . In lung fibroblasts the expression of the IL-6 receptor was enhanced fourfold at a concentration of 10 microg/ml OM-85 BV while that of the IL-11 receptor was not altered . In peripheral blood lymphocytes LIF receptor alpha expression was downregulated in the presence of 10 microg/ml OM-85 BV . At a concentration of 10 microg/ml OM-85 BV enhanced gp130 gene transcription fivefold and increased gp130 protein accumulation in cell membranes by 2.5 times . CONCLUSION: In vitro OM-85 BV exerts immunomodulatory action via modulation of the signal transducer gp130 and gp130 binding cytokines . The increase of IL-6 and IL-11 may explain enhanced T and B cell activity, immunoglobulin synthesis, and IgM to IgG switch . Suppression of IL-12 and LIF receptor-alpha further contributes to organ protection . With regard to gp130 mediated signalling of the investigated cytokines, OM-85 BV modifies the host immune response towards an increased sensitisation of cells to gp130 binding proteins. EMBO J, 2000 Jul 17, 19(14), 3799 - 810 Uncoupling DNA translocation and helicase activity in PcrA: direct evidence for an active mechanism; Soultanas P et al.; DNA footprinting and nuclease protection studies of PcrA helicase complexed with a 3'-tailed DNA duplex reveal a contact region that covers a significant region of the substrate both in the presence and absence of a non-hydrolysable analogue of ATP, ADPNP . However, details of the interactions of the enzyme with the duplex region are altered upon binding of nucleotide . By combining this information with that obtained from crystal structures of PcrA complexed with a similar DNA substrate, we have designed mutant proteins that are defective in helicase activity but that leave the ATPase and single-stranded DNA translocation activities intact . These mutants are all located in domains 1B and 2B, which interact with the duplex portion of the DNA substrate . Taken together with the crystal structures, these data support an 'active' mechanism for PcrA that involves two distinct ATP-dependent processes: destabilization of the duplex DNA ahead of the enzyme that is coupled to DNA translocation along the single strand product. Perit Dial Int, 2000 May-Jun, 20(3), 295 - 300 Phenotypic alterations of recruited eosinophils in peritoneal fluid eosinophilia; Hellman C et al.; OBJECTIVE: To characterize eosinophils and soluble factors in effluent from continuous ambulatory peritoneal dialysis (CAPD) patients and connect these findings to related conditions with eosinophilic accumulation . PATIENTS: Three newly started CAPD patients, two with peritoneal fluid eosinophilia (PFE) and one with bacteria-induced peritonitis . One patient with PFE was followed up for 10 visits during a 7-month period . METHODS: Leukocytes were analyzed in dialysate and peripheral blood from the patients, by flow cytometry, and soluble mediators by ELISA or CAP technique . RESULTS: We found an increased number of neutrophils in the effluent from the patient with bacteria-induced peritonitis; accumulation of eosinophils in combination with negative cultures was noted in the patients with PFE . Increased levels of interleukin (IL)-5 and eosinophil cationic protein, but equal levels of eotaxin, were found in effluent from the PFE patients compared to the patient with neutrophilia . Peritoneal fluid eosinophils were activated by means of EG2, CD11b, CD9, and CD69 expression . Compared to blood eosinophils, the cytokine receptors for IL-5 and granulocyte-macrophage colony-stimulating factor, but not IL-3, were down regulated . CONCLUSION: The finding of activated eosinophils in combination with IL-5 and eotaxin in PFE indicates existing similarities between PFE and conditions found during recruitment of eosinophils in allergic inflammatory responses. Rinsho Byori, 2000 Jun, 48(6), 505 - 9 {Surgical stress and CARS: involvement of T cell loss due to apoptosis}; Iwagaki H et al.; The term compensatory anti-inflammatory response syndrome(CARS) is the cytokine antagonist cascade which down-regulates the inflammatory cascade that appeared to contribute to the onset of bacterial infection . CARS represents immunosuppression, in which state reduced numbers of T cells in blood were encountered . Here we have determined whether this T cell loss is a consequence of bacterial antigen-mediated activation-induced cell death(AICD) . By flowcytometric analysis, less than 0.3% of freshly isolated T cells from healthy volunteers and patients with severe pneumonia were identified as apoptosis . However, during culture, the rate of apoptosis in peripheral blood T cells from patients was 3.0 + 0.9%, and increased further in the presence of anti-CD3(7.4 + 2.1%) and decreased when IL-2 was added(4.4 + 1.3%) . In contrast, there were no changes observed in healthy volunteers on addition of anti-CD3 . Further, anti-CD3 significantly increased susceptibility to apoptosis of CD45RO+ T cells, but not CD45RA+ T cells from patients . Collectively, these findings demonstrated that bacteria-reactive T cells were more susceptible to AICD, and AICD of CD45RO+ T cells, therefore, provides an explanation for the loss of bacteria-reactive T cells during CARS. Pol Merkuriusz Lek, 2000 Apr, 8(46), 272 - 3 {Prevalence of Helicobacter pylori-specific IGG and IGA in children and adolescents with chronic renal failure}; Zwolinska D et al.; Helicobacter pylori, a bacteria first described in 1984, since that time is linked with chronic gastritis and duodenitis . Dyspeptic symptoms and chronic gastritis are common in patients with chronic renal failure (CRF) . The aim of the study was to evaluate of Helicobacter pylori-specific IgG and IgA prevalence in 73 CRF children and possible link of H . pylori infection and dyspeptic symptoms . Anti-H . pylori IgG antibodies were present in 20.5% CRF children (treated conservatively--21%; on CAPD--9%; chronically hemodialysed--29.6%), IgA antibodies was present only in 3 dialysed children (4.1%) . Comparing to adult CRF patient, a lower rate of H . pylori infection was observed . No correlation between H . pylori seropositivity and a presence of dyspeptic symptoms was observed . Prevalence of H . pylori antibodies was higher in older CRF children and adolescents. Arkh Patol, 2000 May-Jun, 62(3), 33 - 7 {Structural organization of sigmoid and rectum wall in patients with cancer after use of enterosorbent with adsorbed metronidazole}; Maiborodin IV et al.; Preoperative preparation with enterosorbent SUMS-1 followed by lavage improves microcirculation in the colon wall and decreases issue of toxins and antigens from the colon lumen as compared to lavage alone . Oral use of the sorbents in the presurgical period in patients with colon carcinoma allows to protect lymphatic and blood system from excessive resorption of toxins, bacteria and metabolites and rapidly decrease the degree of the inflammation in the wall of the organ. Tuber Lung Dis, 2000, 80(1), 5 - 13 Immunization with f-Met peptides induces immune reactivity against Mycobacterium tuberculosis; Dow SW et al.; OBJECTIVE: To determine whether synthetic peptides containing an amino terminal formyl-methionine residue and corresponding to the sequence of several proteins produced by Mycobacterium tuberculosis, would elicit an immune response in mice . DESIGN: Peptides corresponding to the amino termini of 8 M . tuberculosis proteins and initiating with formyl methionine residues were synthesized . The ability of these peptides to bind to the mouse non-classical MHC class I molecule H-2M3a was determined by flow microfluorimetry . These peptides were used to pulse dendritic cells that were then injected into normal mice . These mice were subsequently challenged with aerosolized M . tuberculosis and, 30 days later, the number of viable bacteria in the lungs was determined . RESULTS: Four of the 8 synthetic peptides bound to H-2M3a and stabilized its expression on the cell surface . Injection of mice with dendritic cells pulsed with H-2M3a binding peptides elicited non-MHC restricted cytotoxic T lymphocytes that killed peptide pulsed target cells and macrophages infected with M . tuberculosis . Immunization of mice with syngeneic dendritic cells pulsed in vitro with 2 of these peptides led to retardation of the growth of M . tuberculosis following aerosol challenge . CONCLUSION: Peptides that bind to non-polymorphic class I molecules can elicit immune reactivity directed towards M . tuberculosis. Cell Immunol, 2000 Jun 15, 202(2), 136 - 9 Potential role of CagA in the inhibition of T cell reactivity in Helicobacter pylori infections; Paziak-Domanska B et al.; The pathogenicity of chronic gastroduodenal diseases is very often related to Helicobacter pylori infections . Most H . pylori strains carry the cagA gene encoding an immunodominant 120- to 128-kDa protein which is considered a virulence marker . The majority of CagA-positive H . pylori isolates also produce a 95-kDa protein cytotoxin (VacA) causing vacuolation and degradation of mammalian cells . In our previous study we have shown that live H . pylori bacteria and their sonicates inhibit PHA-driven proliferation of human T lymphocytes . The H . pylori CagA and VacA proteins were suspected of a paralyzing effect of H . pylori on T cell proliferation . In this report, by using isogenic H . pylori mutant strains defective in CagA and VacA proteins, we determined that CagA is responsible for the inhibition of PHA-induced proliferation of T cells . Arch Microbiol, 2000 May-Jun, 173(5-6), 403 - 11 Stigmatella aurantiaca Sg a15 carries genes encoding type I and type II 3-deoxy-D-arabino-heptulosonate-7-phosphate synthases: involvement of a type II synthase in aurachin biosynthesis; Silakowski B et al.; 3-Deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthases catalyse the first step of the shikimate pathway . Two unrelated DAHP synthase types have been described in plants and bacteria . Two type II (aroA(A2) and aroA(A5)) and one type I DAHP synthase gene (aroA001) were identified from the myxobacterium Stigmatella aurantiaca Sg a15 . Inactivation of aroA(A5) leads to a mutant that is impaired in the biosynthesis of aurachins, which are electron transport inhibitors and contain an anthranilate moiety . Feeding of anthranilic acid to the mutant culture restores production of aurachins . Inactivation of aroA(A2) and aroA001 does not impair production of aurachins or other known secondary metabolites of S . aurantiaca Sg a15. Arch Microbiol, 2000 May-Jun, 173(5-6), 352 - 7 Growth phase and metal-dependent regulation of the dpsA gene in Synechococcus sp . strain PCC 7942, USA; Sen A et al.; The Synechococcus sp . strain PCC 7942 dpsA gene encodes a stress-inducible DNA-binding protein whose transcription increases in the stationary phase . Such transcription is likely under the control of an alternative sigma factor . Our current work indicated that dpsA transcription is also important under metal-ion limitation, because dpsA mRNA levels increased 12-fold under low-iron conditions, and that dpsA function is essential for growth under iron-limiting conditions . Promoter activity of the dpsA-promoter-lacZ reporter gene constructs implied that a region of dyad symmetry centered 28 nucleotides from the transcription start is required for metal-dependent repression, as judged by the level of lacZ induction following treatment of cultures with the chelator 2,2'-dipyridyl . This potential operator sequence is distinct from the site recognized by the cyanobacterial Fur repressor homologue . No other nutrient stresses (nitrogen, sulfur, phosphorus) yielded the high level of induction seen following chelator treatment . These studies suggest that there may be more than one class of metal-dependent repressor in cyanobacteria. Coll Antropol, 2000 Jun, 24(1), 151 - 5 Preventive sealing of dental fissures with Heliosil: a two-year follow-up; Rajic Z et al.; Due to their shape and configuration of dental crown, especially its biting surface with numerous pits and fissures permanent molars are suitable sites for retaining food remnants and bacteria . For this reason, preventive efforts and early prophylactic procedures should prevent the development of caries at these critical sites . Deciduous and permanent teeth of 300 children aged 6-7 years with healthy parallel teeth were included in the study . Fissure sealing was performed on one side, whereas contralateral teeth served as controls . During a two-year period, control examinations with finding recording were performed every six months . During the two-year follow-up period, the sealed teeth remained free of caries as long as the coating persisted . In deciduous teeth, the sealant was first observed to be missing at 18 months in 5%, and at 24 months in 8% of the teeth . None of these teeth was affected by caries, suggesting that a part of the sealant was retained in the fissures . In permanent teeth, caries developed in 18% of the sealed teeth at 24 months. Mutat Res, 2000 Jul 20, 452(1), 51 - 6 Mutation spectra induced by replication of two vicinal oxidative DNA lesions in mammalian cells; Gentil A et al.; Ionizing radiations often induce multiple and clustered DNA lesions at the site of DNA interaction . As a model, we have studied the toxicity and the mutagenicity of two adjacent oxidative bases as clustered DNA lesions in mammalian cells using shuttle vectors . The chosen oxidative lesions were 8-oxo-7,8-dihydroguanine, the formylamine residue resulting from the oxidation of a pyrimidine base and the tandem lesion 8-oxo-7,8-dihydroguanine/formylamine where both modifications are located at a vicinal position . A single-stranded DNA shuttle vector carrying a unique DNA lesion was constructed, transfected into simian COS7 cells and mutations induced after replication in mammalian cells were screened in bacteria . 8-oxo-7,8-dihydroguanine, as expected, does not affect greatly survival (70% bypass) whereas formylamine and the tandem lesions are blocking alterations, DNA polymerase bypass being of 45% and 17%, respectively . Base insertion opposite the lesion was studied . Under our experimental conditions, replication of 8-oxo-7, 8-dihydroguanine finally gives rise to guanine:cytosine pairing, rendering this lesion only slightly mutagenic . This is not the case for the formylamine that codes preferentially for adenine (71%) . In addition, one-base deletions were observed targeted to the site to the lesion . Cytosine and thymine were inserted opposite the lesion with similar but low frequencies . Thus, coding properties of the formylamine render this residue very mutagenic when coming from the oxidative alteration of a cytosine . The coding properties of the tandem damage are a combination of the contribution of the two isolated lesions with a very high percentage of adenine insertion (94%) opposite the formylamine residue of the tandem lesion . The toxicity as well as the mutation spectrum of the tandem lesion allow us to speculate about the molecular mechanism with which the DNA polymerase replicates these two lesions. Acta Otolaryngol, 2000 Mar, 120(3), 420 - 3 Nasal nitric oxide is reduced in patients with HIV; Palm J et al.; The gas nitric oxide (NO) is present in high concentrations in human nasal airways . Since NO is known to inhibit the growth of bacteria and viruses, it has been suggested that airborne NO represents the first line of defence against pathogens in the upper airways . Low nasal NO levels have been reported previously in patients susceptible to upper airway infection . Since HIV-positive patients are at risk for respiratory tract infections, including sinusitis, we studied the levels of NO in the upper and lower airways of these patients . A cross-sectional study with age-matched HIV patients and controls was carried out . Nasal and orally exhaled NO were measured in 31 HIV patients and 26 controls using a well-established chemiluminescence method developed for measurements of gaseous NO in the airways . Nasal NO was 21%, lower (p < 0.05, Student's t-test) in HIV patients than in controls, whereas orally exhaled NO did not differ between the two groups . We conclude that nasal NO is reduced in patients with HIV infection . The reduction in nasal NO may contribute to the decreased resistance to airway infections in these patients. J Trop Pediatr, 2000 Jun, 46(3), 167 - 72 Intestinal nematodes, Toxocara infection, and pyogenic liver abscess in children: a possible association; Moreira-Silva SF et al.; Eosinophilia and intestinal helminths are frequent in children with pyogenic liver abscess (PLA) diagnosed in Vitoria (Brazil) . For these reasons we hypothesized that nematode infection with larvae migrating through the tissues (Ascaris, Strongyloides, Ancylostoma, Necator and Toxocara) may be a predisposing factor for PLA in children . We compared the prevalence of intestinal helminth and Toxocara infection between children with PLA and a control group of children with no evidence of PLA at the Children's Hospital N.S . da Gloria in Vitoria . From October 1996 to February 1998, 13 children with PLA and 110 children with diseases other than PLA provided five stool samples (Hoffman, Baerman and Kato-Katz methods) and one blood sample for anti-Toxocara antibodies (ELISA IgG, with previous adsorption with Ascaris suum antigen) . All PLA and comparison children belonged to a low socioeconomic class and lived in similar conditions . The frequency of intestinal nematodes and anti-Toxocara antibodies were significantly higher in PLA patients than in controls (intestinal helminths: 10/13 or 76.9 per cent in PLA cases and 31/110 or 28.1 per cent in controls; OR = 8.94; 95 per cent confidence interval (CI): 1.97 < OR < 50.06; anti-Toxocara antibodies: 9/13 or 69.2 per cent in PLA and 31/110 or 28.1 per cent in controls; OR = 6.59; 95 per cent CI: 1.65 < OR < 31.05) . Moreover, the degree of eosinophilia was higher in PLA patients . Malnutrition was present in both groups . Hemoglobin was 9.5 g/dl in PLA patients and 9.7 g/dl in controls; p = 0.900 . Serum levels of IgA and IgM were normal or above normal, with no difference between the two groups, but the levels of IgG and IgE were higher in PLA patients . Although there is some missing data in respect to some socioeconomic parameters in affected and comparison groups . these results support the hypothesis that helminth infection with larvae migrating through tissues may be a predisposing factor for PLA in children . Th2 cell activation and downregulation of Th1 cells, induced by helminths, thus reducing the microbicidal activity of phagocytes, as well as the granulomatous reaction around the larvae (mainly of Toxocara sp.) causing the trapping of bacteria in liver, may be possible explanations for the increased risk for PLA in children with intestinal nematodes and/or Toxocara infection. J Biol Chem, 2000 Sep 22, 275(38), 29407 - 12 Differences between cystic fibrosis transmembrane conductance regulator and HisP in the interaction with the adenine ring of ATP; Berger AL et al.; The cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel is a member of the ATP-binding cassette transporter family . The most conserved features of this family are the nucleotide-binding domains . As in other members of this family, these domains bind and hydrolyze ATP; in CFTR this opens and closes the channel pore . The recent crystal structures of related bacterial transporters show that an aromatic residue interacts with the adenine ring of ATP to stabilize nucleotide binding . CFTR contains six aromatic residues that are candidates to coordinate the nucleotide base . We mutated each to cysteine and examined the functional consequences . None of the mutations disrupted channel function or the ability to discriminate between ATP, GTP, and CTP . We also applied {2-(triethylammonium)ethyl} methanethiosulfonate to covalently modify the introduced cysteines . The mutant channels CFTR-F429C, F430C, F433C, and F1232C showed no difference from wild-type CFTR, indicating that either the residues were not accessible to modification, or cysteine modification did not affect function . Although modification inactivated CFTR-Y1219C more rapidly than wild-type CFTR, and inactivation of CFTR-F446C was nucleotide-dependent; failure of these mutations to alter gating suggested that Tyr(1219) and Phe(446) were not important for nucleotide binding . The results suggest that ATP binding may not involve the coordination of the adenine ring by an aromatic residue analogous to that in some bacterial transporters . Taken together with earlier work, this study points to a model in which most of the binding energy for ATP is contributed by the phosphate groups. Ups J Med Sci, 2000, 105(1), 31 - 40 Morphologic conversion of Helicobacter pylori from spiral to coccoid form . Scanning (SEM) and transmission electron microscopy (TEM) suggest viability; Willen R et al.; Helicobacter pylori is a pathogen associated with type B gastritis, peptic ulcer disease, gastric atrophy, and stomach cancer . H . pylori exists in two morphological forms, spirals and coccoids . The latter has been described as viable but non-cultivable . The role of the coccoid form in the pathogenesis of gastric disease is disputed . Some authors consider the coccoid form to be a degenerative or dead form of H . pylori, while others consider it a resting but still metabolically active form . This study reports the conversion from spiral to coccoid form ultrastructurally . Dense material is accumulated in the periplasmic space, the spiral bacteria bend and the outer membrane is separated from the inner cell wall layer . Remodeling of inner structures takes place, ending in the coccoid form of the bacteria with preserved light polyphosphate areas . Reduction of surface takes place by production of surface membrane vesicles, which later are squeezed off . The finding of preserved subcellular structures and intact double membranes in combination with degenerative forms suggests that some of the coccoids are viable . Scanning electron microscopy (SEM) demonstrates coccoid form of bacteria with slightly ruffled surfaces but no spiral forms. Acta Med Port, 1999 Dec, 12(12), 371 - 9 {Atypical mycobacteria infections}; Sarmento e Castro RS et al.; The isolation of nontuberculous mycobacteria was considered for many years as a result of contamination or transient colonization . The role of these bacteria in human disease was recognized only after 1950 . They were present almost exclusively in patients with underlying pulmonary pathology and were rare . The prevalence of disease caused by nontuberculous mycobacteria was dramatically increased with the AIDS epidemic . Disseminated infection with MAC and other atypical mycobacteria is nowadays a frequent complication of AIDS . The authors describe some epidemiological and clinical features of these nontuberculous mycobacteria emphasizing the role of MAC and make some considerations about the diagnosis, prophylaxis and treatment of these diseases . The authors end by presenting their own clinical experience. Virology, 2000 Jul 20, 273(1), 127 - 38 Identification and characterization of a 30K protein (Ad4E3-30K) encoded by the E3 region of human adenovirus type 4; Li Y et al.; Human adenovirus type 4 (Ad4), the sole member of subgroup E, contains an open reading frame in the E3 region predicted to encode a unique 30-kDa protein (named Ad4E3-30K) . Ad4E3-30K is predicted to be an integral membrane protein containing an N-terminal signal sequence, a lumenal domain, a transmembrane domain near the C-terminus, and a 37-amino-acid cytoplasmic tail . To determine whether this protein is expressed, rabbit polyclonal antisera were raised against 30K-containing fusion proteins expressed in bacteria . A 30K protein was detected by immunoprecipitation from cell-free translation products and from Ad4-infected A549 cells radiolabeled in the presence of tunicamycin . The protein was detected at only low levels in infected cells . It was not synthesized by a mutant with a large E3 deletion that includes the Ad4E3-30K gene . This mutant grows as well as wild-type Ad4 in culture . Features of Ad4E3-30K were characterized in different transient expression systems . The protein underwent glycosylation by addition of approximately six asparagine-linked oligosaccharides . These glycans were sensitive to endoglycosidase H, indicating that they were either high-mannose or hybrid types, but not complex types, and that the protein did not pass through the Golgi apparatus . Immunofluorescence staining of transfected cells revealed that Ad4E3-30K was localized primarily in the endoplasmic reticulum and nuclear envelope . Biochem Biophys Res Commun, 2000 Jul 14, 273(3), 942 - 7 Location of a cytoplasmic epitope for monoclonal antibody HK 12.18 on H,K-ATPase alpha subunit; Smolka AJ et al.; The enzyme responsible for gastric acidification is a heterodimeric (alpha and beta subunit) P-type ATPase, an integral protein of parietal cell apical membranes, which promotes electroneutral exchange of exoplasmic K(+) for cytoplasmic H(3)O(+) . The molecular mechanisms of the catalytic exchange reaction are imperfectly understood, and await clarification of the precise topology of the enzyme with respect to the secretory membrane . Antibodies directed against H,K-ATPase subunits have been useful in confirming hydropathy plot predictions of HKalpha and HKbeta secondary structure . The monoclonal antibody HK 12.18, which labels gastric mucosal parietal cells by immunocytochemistry, and which binds to a single M(r) approximately 94,000 polypeptide by SDS-PAGE immunoblot of gastric microsomes, has been widely used as a specific marker of parietal cells in clinical and cell biological studies of acid secretion, and as a specific HKalpha probe in biochemical studies . However, the uncertain location of the HK 12.18 epitope has limited the antibody's usefulness as a topology probe . In this study, HK 12 . 18 immune reactivity with native H,K-ATPase tryptic peptides, HKalpha cDNA fragments expressed in bacteria, and overlapping synthetic HKalpha tridecapeptides, was used to identify the HK 12.18 epitope as seven consecutive amino acids (Asp(682)-Met-Asp-Pro-Ser-Glu-Leu(688)) in the cytoplasmic middle third of HKalpha . J Mol Biol, 2000 Jul 21, 300(4), 687 - 95 Extended sugar slide function for the periplasmic coiled coil domain of ScrY; Dumas F et al.; Several bacterial outer membrane proteins have a periplasmic extension whose structure and function remain elusive . Here, the structure/function relationship of the N-terminal periplasmic domain of the sucrose-specific outer membrane channel ScrY was investigated . Circular dichroism and analytical centrifugation demonstrated that the N-terminal domain formed a parallel, three-stranded coiled coil . When this domain was fused to the maltose-specific channel LamB, permeation of maltooligosaccharides in liposomes increased with increasing sugar chain length whereas wild-type LamB showed the opposite effect . Current fluctuation analysis demonstrated increased off-rates for sugar transport through the fusion protein . Moreover, equilibrium dialysis showed an affinity of sucrose for the isolated N-terminal peptide . Together these results demonstrate a novel function for coiled coil domains, operating as an extended sugar slide . J Mol Biol, 2000 Jul 21, 300(4), 663 - 75 Early evolution of cytochrome bc complexes; Schutz M et al.; Primary structures, functional characteristics and phylogenetic relationships of subunits of cytochrome bc complexes from phylogenetically diverse bacterial and archaeal species were analysed . A single case of lateral gene transfer, i.e . the import of an epsilon-proteobacterial cytochrome bc(1) complex into Aquificales, was identified . For the enzyme in the remainder of the species studied, the obtained phylogenies were globally in line with small subunit rRNA trees . The distribution of a few key phylogenetic markers, such as contiguousness of cytochrome b, nature of the c-type subunit or spacing between b-heme ligands, are discussed . A localised modification of previous tree topologies is proposed on the basis of the obtained data . The comparison of extant enzymes furthermore allowed us to define the minimal functional and evolutionary core of the enzyme . The data furthermore suggest that the ancestral enzyme was put together from subunits that previously had played a role in other electron transfer chains . Biochemistry, 2000 Jul 11, 39(27), 7902 - 9 Water structural changes involved in the activation process of photoactive yellow protein; Kandori H et al.; Fourier transform infrared (FTIR) spectroscopy was applied to the blue-light photoreceptor photoactive yellow protein (PYP) to investigate water structural changes possibly involved in the photocycle of PYP . Photointermediates were stabilized at low temperature, and difference IR spectra were obtained between intermediate states and the original state of PYP (pG) . Water structural changes were never observed in the >3570 cm(-)(1) region for the intermediates stabilized at 77-250 K, such as the red-shifted pR and blue-shifted pB intermediates . In contrast, a negative band was observed at 3658 cm(-)(1) in the pB minus pG spectrum at 295 K, which shifts to 3648 cm(-)(1) upon hydration with H(2)(18)O . The high frequency of the O-H stretch of water indicates that the water O-H group does not form hydrogen bonds in pG, and newly forms these upon pB formation at 295 K, but not at 250 K . Among 92 water molecules in the crystal structure of PYP, only 1 water molecule, water-200, is present in a hydrophobic core inside the protein . The amide N-H of Gly-7 and the imidazole nitrogen atom of His-108 are its possible hydrogen-bonding partners, indicating that one O-H group of water-200 is free to form an additional hydrogen bond . The water band at 3658 cm(-)(1) was indeed diminished in the H108F protein, which strongly suggests that the water band originates from water-200 . Structural changes of amide bands in pB were much greater in the wild-type protein at 295 K than at 250 K or in the H108F protein at 295 K . The position of water-200 is >15 A remote from the chromophore . Virtually no structural changes were reported for regions larger than a few angstroms away from the chromophore, in the time-resolved X-ray crystallography experiments on pB . On the basis of the present results, as well as other spectroscopic observations, we conclude that water-200 (buried in a hydrophobic core in pG) is exposed to the aqueous phase upon formation of pB in solution . In neither crystalline PYP nor at low temperature is this structural transition observed, presumably because of the restrictions on global structural changes in the protein under these conditions. Vet Microbiol, 2000 Jul 31, 75(2), 177 - 88 IgG isotype antibody responses to epitopes of the Mycobacterium bovis protein MPB70 in immunised and in tuberculin skin test-reactor cattle; Lightbody KA et al.; Serological assays may have merit in identifying animals in advanced stages of bovine tuberculosis, but most tests have had sub-optimal sensitivities and specificities . The Mycobacterium bovis protein MPB70 has been identified as a B-cell target with diagnostic potential in measurement of pre- and post-skin-test antibody responses . One observation, which has potential practical application, has been that skin testing with tuberculin boosts IgG(1) anti-MPB70 antibody responses in cattle with tuberculous lesions . However, serological cross-reactivities with bacteria, such as Nocardia asteroides, have been described for this protein . With the aim of identifying candidate reagents for improved diagnostic tests, this study investigated IgG isotype antibody responses to MPB70 at the epitope level and, because of the previous findings, focused on IgG(1) responses following skin testing . Screening of a panel of overlapping synthetic peptides using sera from cattle immunised with MPB70 and cattle infected with M . bovis showed that two regions of the protein (residues 21-70 and 101-120) contain dominant B-cell epitopes . No individual epitope appeared to be selectively recognised by one isotype of IgG antibody . Investigation of IgG(1) responses showed that recognition of the epitope within residues 51-70 was boosted strongly by tuberculin injections in skin-test positive cattle and that this memory response was generally a feature of cattle which were found to have macroscopic, tuberculous lesions. Vet Microbiol, 2000 Jul 31, 75(2), 109 - 26 Chlamydia and Chlamydiales: more than meets the eye; Everett KD; This review summarizes the dramatic changes that have occurred in the taxonomy of bacteria known as Chlamydia . Best known for the diseases they cause in humans, these intracellular bacteria also comprise many species that are responsible for a wide variety of clinically and economically important diseases in livestock and companion animals . The old taxonomy grouped most of these species into C . psittaci because systematic methods for routinely distinguishing them were not available . DNA-based testing methods are now available that distinguish different chlamydial families, genera, and species . This summary reviews these tests and a number of oligonucleotide primers that distinguish these groups using PCR and PCR-RFLP . DNA-based methods are also being used to discover new families of chlamydia-like bacteria, at least one of which is responsible for abortion in cattle (Waddlia chondrophila) . This review summarizes the pathogenic roles of the Chlamydiaceae, new families, and individual species within the order Chlamydiales . These discoveries create opportunities for veterinarians to carry out epidemiological studies of chlamydiae that previously were not possible. J Microbiol Methods, 2000 Jul, 41(2), 155 - 60 Heteroduplex mobility assay as a tool for predicting phylogenetic affiliation of environmental ribosomal RNA clones; Bowyer J et al.; Heteroduplex mobility assay (HMA) of partial 16S rRNA gene fragments was tested as a tool for predicting bacterial phylogenetic relationships . Approximately 400-bp fragments were amplified from a selection of cloned environmental DNAs representing a range of sequence identities and phylogenetic relationships . Heteroduplexes between pairs of sequences were formed by mixing equal amounts of PCR products, denaturing and annealing . Annealed mixes were separated on 8% polyacrylamide gels and silver stained . Heteroduplexes were readily distinguished from reannealed homoduplex and unannealed fragments in all sequences where percentage identity was less than 95% . The heteroduplexes showed retarded electrophoretic migration with respect to homoduplexes . The relative retardation was strongly correlated to the percentage sequence identity between the two strands . The HMA is a useful tool for screening environmental clone libraries to systematically select clones representative of the phylogenetic diversity within the sample, or to selectively retrieve members of a particular phylogenetic group for more detailed study. Eur J Surg Suppl, 1999, (584), 73 - 8 Relation of the bi-allelic NcoI restriction fragment length polymorphism within the tumour necrosis factor B gene to the development of mediastinitis; Schade FU et al.; During recent years the dual role of endogenous inflammatory mediators such as tumour necrosis factor (TNF) has become evident . While TNF has been recognised to possess a great detrimental potential, for example in the case of sepsis, it is on the other hand an integral component of an adequate immune response to bacterial invasion . These different properties of TNF and others seem to be dependent mainly on the quantitative extent of their formation . Some recent findings indicate that this extent may in part be determined genetically . The classification of patients according to polymorphic cytokine genes might, therefore, predict some of their reactions to septic challenges. Genes Dev, 2000 Jul 1, 14(13), 1651 - 63 A family of rhomboid-like genes: Drosophila rhomboid-1 and roughoid/rhomboid-3 cooperate to activate EGF receptor signaling; Wasserman JD et al.; As in mammals, the Drosophila EGF receptor controls many aspects of growth and development . The rate limiting component of Drosophila Egfr signaling is Rhomboid, a seven transmembrane domain protein, whose expression prefigures Egfr signaling . Little is known about the molecular mechanism of Rhomboid function but genetic evidence suggests that it controls the activation of the ligand Spitz, a TGFalpha-like factor . Spitz/Egfr signaling regulates cell determination in the eye but here there is no apparent function for Rhomboid, an observation that casts doubt on this prevailing model of Rhomboid function . We describe our identification of six new rhomboid-like genes in Drosophila, and a large family of related genes present in organisms as diverse as bacteria and mammals; a human rhomboid homolog has also recently been described . Drosophila rhomboid-3 corresponds to the roughoid mutation; it cooperates with rhomboid-1 to control Egfr signaling in the eye, thereby solving the puzzle of the apparent lack of Rhomboid-1 function there . Rhomboid-1 and Roughoid/Rhomboid-3 act in the signal-emitting not signal-receiving cell, supporting the idea that Spitz activation is regulated by Rhomboid-like molecules. Masui, 2000 Jun, 49(6), 652 - 4 {Accidental decrease in the air flow during air/oxygen sevoflurane anesthesia}; Okuyama M et al.; We describe our experience of an accidental decrease in the air flow during air/oxygen sevoflurane anesthesia . According to the malfunction of an air compressor system, dehydration of the compressed air was inadequate, and the wet air was delivered to the anesthesia machine . The moisture was formed at a flow control valve to cause a gradual decrease in the air flow . The low-pressure alarm did not work at that time, because the pressure of the air supply was normal . There are two types of medical air, one is produced from the ambient air by air compressor system and another is the synthetic air which is a mixture of oxygen and nitrogen . Although the synthetic air is always dry and clean, the former contains dust, bacteria, and moisture . There is a possibility that all of these particles cannot be excluded before use . Accordingly, we must check the air compressor system routinely when a source of the compressed air is used. J Mol Biol, 2000 Jul 14, 300(3), 587 - 95 Structure of a thioredoxin-like {2Fe-2S} ferredoxin from Aquifex aeolicus; Yeh AP et al.; The 2.3 A resolution crystal structure of a {2Fe-2S} cluster containing ferredoxin from Aquifex aeolicus reveals a thioredoxin-like fold that is novel among iron-sulfur proteins . The {2Fe-2S} cluster is located near the surface of the protein, at a site corresponding to that of the active-site disulfide bridge in thioredoxin . The four cysteine ligands are located near the ends of two surface loops . Two of these ligands can be substituted by non-native cysteine residues introduced throughout a stretch of the polypeptide chain that forms a protruding loop extending away from the cluster . The presence of homologs of this ferredoxin as components of more complex anaerobic and aerobic electron transfer systems indicates that this is a versatile fold for biological redox processes . Cad Saude Publica, 1997, 13 Suppl 1, 7 - 13 {Stomach cancer: risk factors}; Britto AV; For the last fifty years, stomach cancer has become less important in terms of morbidity and mortality in developed countries, but the same pattern has not occurred in Brazil . The main risk factors for this neoplasm are certain diet patterns that became evident through epidemiological studies in various population groups . After the carcinogenic effects of nitrosamines and the anti-oxidant activity of vitamin C were discovered, some of the associations between stomach cancer and diet were partially understood . After the description of Helicobacter pylori in 1983 and the evidence of the relationship between this bacteria and certain stomach diseases, new elements were added to the knowledge about the development of this neoplasm . Current knowledge, albeit incomplete, provides interesting prospects for the prevention and early diagnosis of stomach cancer. Anaesthesist, 2000 May, 49(5), 446 - 50 {Significance of perfusion of the gastrointestinal tract in shock}; Frey L et al.; The splanchnic perfusion is reduced early in the course of any shock . The mucosa of the gut suffers most as it experiences a high oxygen demand even in the steady state . The specific arrangement of the micro vessels within the villus of the mucosa exposes the tip of the villus at the highest risk for ischemia, particularly in low flow states . As a consequence the integrity of the mucosal layer is compromised and dysfunction of the mucosal barrier may allow bacteria and toxins to translocate from the gut lumen . Activation of leukocytes and stimulation of cytokine synthesis may comprise a sustained inflammatory response syndrome . So far there is a good body of evidence that the splanchnic region may play an important role in the pathophysiological sequence from shock to organ dysfunction. Clin Diagn Lab Immunol, 2000 Jul, 7(4), 676 - 81 Evaluation of human FcgammaRIIA (CD32) and FcgammaRIIIB (CD16) polymorphisms in Caucasians and African-Americans using salivary DNA; van Schie RC et al.; Two classes of low-affinity receptors for the Fc region of immunoglobulin G (IgG) (FcgammaR) are constitutively expressed on resting human neutrophils . These receptors, termed FcgammaRIIa (CD32) and FcgammaRIIIb (CD16), display biallelic polymorphisms which have functional consequences with respect to binding and/or ingestion of targets opsonized by human IgG subclass antibodies . The H131-R131 polymorphism of CD32 influences binding of human IgG2 and, to a lesser extent, human IgG3 to neutrophils . The neutrophil antigen (NA1-NA2) polymorphism of CD16 influences the efficiency of phagocytosis of bacteria opsonized by human IgG1 and IgG3 . These polymorphisms may influence host susceptibility to certain infectious and/or autoimmune diseases, prompting interest in the development of facile methods for determination of CD32 and CD16 genotype in various clinical settings . We previously reported that genomic DNA from saliva is a suitable alternative to DNA from blood in PCR-based analyses of CD32 and CD16 polymorphisms . In the present study, we utilized for the first time this salivary DNA-based methodology to define CD32 and CD16 genotypes in 271 Caucasian and 118 African-American subjects and to investigate possible linkage disequilibrium between certain CD32 and CD16 genotypes in these two ethnic groups . H131 and R131 gene frequencies were 0.45 and 0.55, respectively, among Caucasians and 0.59 among African-Americans . NA1 and NA2 gene frequencies were 0.38 and 0.62 among Caucasians and 0 . 39 and 0.61 among African-Americans . Since FcgammaRIIa and FcgammaRIIIb synergize in triggering neutrophils, we also assessed the frequency of different CD32 and CD16 genotype combinations in these two groups . In both groups, the R/R131-NA2/NA2 genotype combination was more common than the H/H131-NA1/NA1 combination (threefold for Caucasians versus sevenfold for African-Americans) . Whether individuals with the combined R/R131-NA2/NA2 genotype are at greater risk for development of infectious and/or autoimmune diseases requires further investigation, which can be conveniently performed using DNA from saliva rather than blood. J Infect Dis, 2000 Jul, 182(1), 306 - 10 Epub 2000 Jun 30. Evaluation of the latency-associated nuclear antigen (ORF73) of Kaposi's sarcoma-associated herpesvirus by peptide mapping and bacterially expressed recombinant western blot assay; Olsen SJ et al.; Kaposi's sarcoma (KS)-associated herpesvirus open-reading frame (ORF) 73 encodes a latency-associated nuclear antigen (LANA) that is the basis for several serologic assays . Immunoreactive epitopes were searched for by peptide mapping, and 171 cleavable, biotinylated 17-mer peptides offset by 5 residues were synthesized and screened with human serum samples by ELISA . The initial screen, which used highly reactive serum diluted 1:500, identified 38 immunoreactive peptides . These were subsequently tested on additional serum samples diluted 1:40 . Thirteen peptides were more reactive with serum samples from patients with KS than with control serum samples . No single epitope was recognized by most KS patient serum samples . Combined use of these peptides did not increase test sensitivity to that of current indirect immunofluorescence assays for LANA (80%-90%) . For comparison, full-length ORF73 was expressed in bacteria and analyzed by Western blot . The overall sensitivity was 67% (range, 100% among US patients with classic KS to 52% among Italian patients with classic KS) . These studies suggest that LANA immunoreactivity may be due to variations in patient response or conformational epitopes. Nat Struct Biol, 2000 Jun, 7(6), 449 - 55 The SsrA-SmpB system for protein tagging, directed degradation and ribosome rescue; Karzai AW et al.; Bacteria contain a remarkable RNA molecule - known alternatively as SsrA RNA, tmRNA, or 10Sa RNA - that acts both as a tRNA and as an mRNA to direct the modification of proteins whose biosynthesis has stalled or has been interrupted . These incomplete proteins are marked for degradation by cotranslational addition of peptide tags to their C-termini in a reaction that is mediated by ribosome-bound SsrA RNA and an associated protein factor, SmpB . This system plays a key role in intracellular protein quality control and also provides a mechanism to clear jammed or obstructed ribosomes . Here the structural, functional and phylogenetic properties of this unique RNA and its associated factors are reviewed, and the intracellular proteases that act to degrade the proteins tagged by this system are also discussed. Eur J Biochem, 2000 Jul, 267(14), 4406 - 13 Identification and characterization of alternative splice products encoded by the human phosphotyrosyl phosphatase activator gene; Janssens V et al.; The phosphotyrosyl phosphatase activator (PTPA), a protein phosphatase 2A (PP2A) regulatory protein, specifically stimulates the phosphotyrosyl phosphatase activity of PP2A in vitro . Human PTPA is encoded by a single gene, the structure and chromosomal localization of which have been determined in our previous work . In this paper, we report the identification and characterization of six additional splice variants, termed PTPAbeta to PTPAeta, in addition to the originally identified PTPAalpha form . Interestingly, PTPAbeta and PTPAgamma contain a novel exon that had been overlooked in the formerly identified gene structure . As revealed by nested PCR, all these PTPA transcripts are expressed in various human cDNA libraries and cell lines . However, a quantitative approach, using a single PCR reaction followed by detection of the reaction products with a radioactively labeled probe, revealed only PTPAalpha, beta and delta, suggesting that the other transcripts are expressed very poorly . In vitro transcription-translation revealed that only PTPAalpha, beta, delta and epsilon are translated into functional proteins, whereas translation of PTPAgamma, zeta and eta is stopped prematurely due to a frameshift resulting from skipping exon 2, suggesting that the latter isoforms may result from splicing errors . By western analysis of HepG2 and Saos-2 cell extracts, only PTPAalpha and beta were detected . PTPAalpha and beta were expressed as GST fusion proteins in bacteria, and were found to contain the same specific phosphotyrosyl phosphatase stimulatory activity towards PP2A . The identification of this family of PTPA variants adds another level of complexity to the in vivo function(s) of PTPA, opening up the possibility that different isoforms may perform different functions. Proc Natl Acad Sci U S A, 2000 Jul 18, 97(15), 8554 - 9 whmD is an essential mycobacterial gene required for proper septation and cell division; Gomez JE et al.; A study of potential mycobacterial regulatory genes led to the isolation of the Mycobacterium smegmatis whmD gene, which encodes a homologue of WhiB, a Streptomyces coelicolor protein required for sporulation . Unlike its Streptomyces homologue, WhmD is essential in M . smegmatis . The whmD gene could be disrupted only in the presence of a plasmid supplying whmD in trans . A plasmid that allowed chemically regulated expression of the WhmD protein was used to generate a conditional whmD mutant . On withdrawal of the inducer, the conditional whmD mutant exhibited irreversible, filamentous, branched growth with diminished septum formation and aberrant septal placement, whereas WhmD overexpression resulted in growth retardation and hyperseptation . Nucleic acid synthesis and levels of the essential cell division protein FtsZ were unaltered by WhmD deficiency . Together, these phenotypes indicate a role for WhmD in mycobacterial septum formation and cell division. Genetics, 2000 Jul, 155(3), 1449 - 58 Zygotic associations and multilocus statistics in a nonequilibrium diploid population; Yang RC; The usual approach to characterizing and estimating multilocus associations in a diploid population assumes that the population is in Hardy-Weinberg equilibrium . The purpose of this study is to develop a set of summary statistics that can be used to characterize and estimate the multilocus associations in a nonequilibrium population . The concept of "zygotic associations" is first expanded to facilitate the development . The summary statistics are calculated using the distribution of a random variable, the number of heterozygous loci (K) found in diploid individuals in the population . In particular, the variance of K consists of single-locus and multilocus components with the latter being the sum of zygotic associations between pairs of loci . Simulation results show that the multilocus associations in the variance of K are detectable in a sample of moderate size (> or =30) when the sum of all pairwise zygotic associations is greater than zero and when gene frequency is intermediate . The method presented here is a generalization of the well-known development for the Hardy-Weinberg equilibrium population and thus may be of more general use in elucidating the multilocus organizations in nonequilibrium and equilibrium populations. Avian Dis, 2000 Apr-Jun, 44(2), 256 - 65 Identifying agent(s) associated with poult enteritis mortality syndrome: importance of the thymus; Schultz-Cherry S et al.; Poult enteritis mortality syndrome (PEMS), a highly infectious disease of young turkeys, causes serious financial losses to the turkey industry . Clinically, PEMS is defined by mortality profiles, diarrhea, growth depression, and immunosuppression . Although many viruses, bacteria, and parasites are found in PEMS-infected birds, the inciting agent remains unknown . Experimentally, PEMS can be reproduced by exposing naive poults to the intestinal contents from infected birds . Previous reports suggest that extraintestinal tissues fail to reproduce the disease . Histopathologic examination of tissues from PEMS-infected poults suggested that the thymus exhibited the earliest signs of pathology . On the basis of these observations, we hypothesized that the thymus harbors an agent(s) involved in PEMS . In these studies, naive turkey poults were orally inoculated with a bacteria-free filtrate composed of either the intestines and feces or the thymus from PEMS-infected birds and were monitored for clinical signs of PEMS . Poults exposed to a filtrate composed solely of the thymus from PEMS-infected birds exhibited diarrhea, growth depression, mortality, pathology, and, most importantly, immunosuppression similar to poults exposed to the intestinal filtrate . The results of this study suggest that the thymus of infected birds harbors the agent(s) that can reproduce a PEMS-like disease in turkey poults. Radiol Med (Torino), 2000 Mar, 99(3), 165 - 8 {The role of spiral computed tomography in sigmoid diverticulitis and the diagnostic-therapeutic implications}; Scaglione M et al.; PURPOSE: Colonic diverticula are saccules made of colonic mucosa and submucosa that herniate from the colonic lumen through the muscular layer of the wall where straight vessels penetrate . Diverticula are localized in the sigmoid colon in 95% of cases . Bacteria pooling in the lumen may cause lumen erosion and eventually perforation . CT is a useful technique in this condition because it can demonstrate intra- and/or extramural inflammation . Aim of this retrospective study was to assess the capabilities of contrast-enhanced helical Computed Tomography (CT) in sigmoid diverticulitis, especially relative to selection of the appropriate treatment . MATERIAL AND METHODS: We retrospectively reviewed the findings of 41 patients referred to our emergency department for diverticulitis . CT scans were performed 65 seconds after i.v . injection of nonionic contrast material (3 mL/s, 120 mL in all) administered by a CT-power injector . The following 7 CT findings were considered at least suggestive of acute diverticulitis: focal wall thickening, intramural abscess, inflammatory changes in the sigmoid mesentery root, pericolic fat inflammation or pericolic abscess formation, fistula, peritonitis . CT results were compared with surgical and physical findings . RESULTS: Based on CT findings, diverticulitis was classified as mild (25 patients) or severe (15 patients) . In mild diverticulitis we found: focal sigmoid wall thickening (6 patients), intramural abscess (3 patients), sigmoid mesentery root thickening (5 patients), edema fluid (8 patients) and phlegmon (3 patients) . In severe diverticulitis we found: sigmoid mesentery abscess (6 patients), fistula (5 patients) and peritonitis (4 patients) . CT findings were questionable in 1 case and thus we could not exclude a perforated carcinoma . CONCLUSION: Contrast-enhanced helical CT is the imaging modality of choice in assessing mild or severe acute diverticulitis because it provides useful information for appropriate treatment planning in the emergency setting . This technique is most useful in questionable cases and in patients with suspected severe diverticulitis where a choice must be made between different treatment options. Neurol India, 2000 Jun, 48(2), 149 - 54 Primary angiitis of CNS : neuropathological study of three autopsied cases with brief review of literature; Panda KM et al.; Primary angiitis of CNS(PACNS) or granulomatous angiitis of CNS is a rare inflammatory disease of small blood vessels mostly confined to the CNS . The clinical and pathological features of 3 autopsied cases are described . Clinically all the three PACNS patients were young males, age ranging from 19 to 31 years . All presented with varied neurological manifestations . There was no evidence of systemic disease in any of the cases . The ESR was normal and CSF analysis showed chronic meningitic pattern . The cerebral angiogram in one case was normal and the CT scan done in another case showed multiple intracerebral haematoma due to vasculitis . Brain biopsy was not done . Diagnosis was made at post-mortem examination . Histology showed characteristic but variable degree of granulomatous and non-granulomatous angiitis of small vessels . Venulitis with parenchymal haemorrhages was the predominant feature and in one case phlebitis with thrombosis was noted . Since the disease responds to steroids and immunosuppressive therapy, establishing antemortem diagnosis is important . In view of the association of angiitis of CNS with bacteria and viral infections, their role in the evolution of the disease needs to be investigated. J Immunol, 2000 Jul 15, 165(2), 1022 - 9 Helicobacter pylori-induced mucosal inflammation is Th1 mediated and exacerbated in IL-4, but not IFN-gamma, gene-deficient mice; Smythies LE et al.; To elucidate the pathogenesis of Helicobacter pylori-associated gastritis, we studied immune responses of C57BL/6J wild-type (WT), SCID, and gene deficient (IFN-gamma-/- and IL-4-/-) mice following infection with a pathogenic isolate of H . pylori (SPM326) . During early infection in WT mice, mononuclear and polymorphonuclear cells accumulated in the gastric lamina propria, and the numbers of cells in the inflamed mucosa expressing IFN-gamma, but not IL-4, mRNA rose significantly (p < 0.005), consistent with a local Th1 response . Splenic T cells from the same infected WT mice produced high levels of IFN-gamma, no detectable IL-4, and low amounts of IL-10 following in vitro H . pylori urease stimulation, reflecting a systemic Th1 response . Infected C57BL/6J SCID mice did not develop gastric inflammation despite colonization by many bacteria . Infected C57BL/10J and BALB/c mice also did not develop gastric inflammation and displayed a mixed Th1/Th2 splenic cytokine profile . These data imply a major role for the Th1 cytokine IFN-gamma in H . pylori-associated gastric inflammation in C57BL/6J mice . Compared with WT animals, infected IL-4-/- animals had more severe gastritis and higher levels of IFN-gamma production by urease-stimulated splenocytes (p < 0.01), whereas IFN-gamma-/- mice exhibited no gastric inflammation and higher levels of IL-4 production by stimulated splenocytes . These findings establish C57BL/6J mice as an important model for H . pylori infection and demonstrate that up-regulated production of IFN-gamma, in the absence of the opposing effects of IL-4 (and possibly IL-10), plays a pivotal role in promoting H . pylori-induced mucosal inflammation. FEBS Lett, 2000 Jun 30, 476(1-2), 47 - 51 Regulating the cellular economy of supply and demand; Hofmeyr JS et al.; Cellular metabolism is a molecular economy that is functionally organised into supply and demand blocks linked by metabolic products and cofactor cycles . Supply-demand analysis allows the behaviour, control and regulation of metabolism as a whole to be understood quantitatively in terms of the elasticities of supply and demand, which are experimentally measurable properties of the individual blocks . The kinetic and thermodynamic aspects of regulation are clearly distinguished . One important result is the demonstration that when flux is controlled by one block, the other block determines to which degree the concentration of the linking metabolite is homeostatically maintained. J Clin Microbiol, 2000 Jul, 38(7), 2746 - 9 PCR amplification and phylogenetic analysis of groESL operon sequences from Ehrlichia ewingii and Ehrlichia muris; Sumner JW et al.; Broad-range PCR primers were used to amplify part of the groESL operon of the canine pathogen Ehrlichia ewingii, recently recognized as a human pathogen, and the murine pathogen Ehrlichia muris . Phylogenetic analysis supported the relationships among Ehrlichia species previously determined by comparison of 16S rRNA gene sequences . These sequences provide additional PCR targets for species for which few gene sequences have been determined. J Clin Microbiol, 2000 Jul, 38(7), 2740 - 2 Identification of a unique Helicobacter species by 16S rRNA gene analysis in an abdominal abscess from a patient with X-linked hypogammaglobulinemia; Han S et al.; A unique Helicobacter species, MZ640285, was isolated from a patient with X-linked hypogammaglobulinemia suffering from recurrent abdominal abscesses and was identified by 16S rRNA gene sequence analysis . In the phylogenetic tree, the isolate fell into a cluster which included Flexispira rappini, Helicobacter bilis, and Helicobacter sp . strain Mainz . Helicobacters are being increasingly recognized as pathogens in immunocompromised hosts . These fastidious bacteria are not easily cultured in the routine diagnostic laboratory, and this is the first report of their identification by 16S rRNA gene sequencing performed directly from a clinical specimen. J Clin Microbiol, 2000 Jul, 38(7), 2661 - 4 Slaughter pigs are commonly infected by closely related but distinct gastric ulcerative lesion-inducing gastrospirilla; Roosendaal R et al.; An association between (unculturable) gastrospirillum-like organisms (GLO) and ulcerative lesions in the pars oesophagea in stomachs of swine has been claimed . In dogs GLO detected by microscopy may represent several Helicobacter species or subspecies . Therefore we investigated which Helicobacter spp . are present in stomachs of swine and their possible association with ulcerative lesions of the pars oesophagea . The presence of Helicobacter spp . in the antrum and pars oesophagea in 122 stomachs of slaughter swine was determined by microscopy (n = 122), by culture on selective and nonselective media (n = 112), and by a genus-specific 16S ribosomal DNA (rDNA) PCR (n = 80) . GLO could not be cultured . Phylogenetic analysis of 43 16S rDNA fragments (out of 54 PCR-positive biopsy specimens) revealed the presence of Helicobacter heilmannii type 1 in 42 of them . This correlated with the presence of bacteria with GLO morphology . Helicobacter bilis 16S rDNA was amplified directly from one sample harboring bacteria with H . bilis morphology . The association between Helicobacter spp . and gastric lesions was investigated with a second group of 41 pigs with (n = 21 cases) or without (n = 20 controls) gastric lesions . Fifteen of the 21 cases were positive by PCR or microscopy, compared to 7 of 20 of the controls (P = 0.03) . 16S rDNA sequence analysis of 7 of 14 PCR-positive cases revealed the presence of H . heilmannii type 1 . Microscopy showed bacteria with GLO morphology . One sample (cases) was culture negative but PCR positive for Helicobacter pullorum-related 16S rDNA . In conclusion, our findings indicate that H . heilmannii type 1 is the predominant Helicobacter spp . in the stomachs of pigs and that its presence is associated with ulcerative lesions in the pars oesophagea. Appl Environ Microbiol, 2000 Jul, 66(7), 3065 - 72 Development and application of small-subunit rRNA probes for assessment of selected Thiobacillus species and members of the genus Acidiphilium; Peccia J et al.; Culture-dependent studies have implicated sulfur-oxidizing bacteria as the causative agents of acid mine drainage and concrete corrosion in sewers . Thiobacillus species are considered the major representatives of the acid-producing bacteria in these environments . Small-subunit rRNA genes from all of the Thiobacillus and Acidiphilium species catalogued by the Ribosomal Database Project were identified and used to design oligonucleotide DNA probes . Two oligonucleotide probes were synthesized to complement variable regions of 16S rRNA in the following acidophilic bacteria: Thiobacillus ferrooxidans and T . thiooxidans (probe Thio820) and members of the genus Acidiphilium (probe Acdp821) . Using (32)P radiolabels, probe specificity was characterized by hybridization dissociation temperature (T(d)) with membrane-immobilized RNA extracted from a suite of 21 strains representing three groups of bacteria . Fluorochrome-conjugated probes were evaluated for use with fluorescent in situ hybridization (FISH) at the experimentally determined T(d)s . FISH was used to identify and enumerate bacteria in laboratory reactors and environmental samples . Probing of laboratory reactors inoculated with a mixed culture of acidophilic bacteria validated the ability of the oligonucleotide probes to track specific cell numbers with time . Additionally, probing of sediments from an active acid mine drainage site in Colorado demonstrated the ability to identify numbers of active bacteria in natural environments that contain high concentrations of metals, associated precipitates, and other mineral debris. Appl Environ Microbiol, 2000 Jul, 66(7), 2783 - 90 Fate of nitrate acquired by the tubeworm Riftia pachyptila; Girguis PR et al.; The hydrothermal vent tubeworm Riftia pachyptila lacks a mouth and gut and lives in association with intracellular, sulfide-oxidizing chemoautotrophic bacteria . Growth of this tubeworm requires an exogenous source of nitrogen for biosynthesis, and, as determined in previous studies, environmental ammonia and free amino acids appear to be unlikely sources of nitrogen . Nitrate, however, is present in situ (K . Johnson, J . Childress, R . Hessler, C . Sakamoto-Arnold, and C . Beehler, Deep-Sea Res . 35:1723-1744, 1988), is taken up by the host, and can be chemically reduced by the symbionts (U . Hentschel and H . Felbeck, Nature 366:338-340, 1993) . Here we report that at an in situ concentration of 40 microM, nitrate is acquired by R . pachyptila at a rate of 3.54 micromol g(-1) h(-1), while elimination of nitrite and elimination of ammonia occur at much lower rates (0 . 017 and 0.21 micromol g(-1) h(-1), respectively) . We also observed reduction of nitrite (and accordingly nitrate) to ammonia in the trophosome tissue . When R . pachyptila tubeworms are exposed to constant in situ conditions for 60 h, there is a difference between the amount of nitrogen acquired via nitrate uptake and the amount of nitrogen lost via nitrite and ammonia elimination, which indicates that there is a nitrogen "sink." Our results demonstrate that storage of nitrate does not account for the observed stoichiometric differences in the amounts of nitrogen . Nitrate uptake was not correlated with sulfide or inorganic carbon flux, suggesting that nitrate is probably not an important oxidant in metabolism of the symbionts . Accordingly, we describe a nitrogen flux model for this association, in which the product of symbiont nitrate reduction, ammonia, is the primary source of nitrogen for the host and the symbionts and fulfills the association's nitrogen needs via incorporation of ammonia into amino acids. Jpn J Pharmacol, 2000 Feb, 82(2), 95 - 101 The physiological activity and in vivo distribution of dinitrosyl dithiolato iron complex; Ueno T et al.; Nitric oxide (NO) is recognized as an endogenous mediator of vascular tone, a neurotransmitter and an immune effector molecule . Furthermore, it has been implicated in the development of various diseases . Because NO is extremely labile in the biological milieu, its activities can be effected not only by NO itself but also by relatively stable physiologic NO carriers or NO donors . Dinitrosyl iron complexes have been recognized as endogenous NO carrier molecules as well as S-nitrosothiols . The complex has been found in cells and the tissues of mammals and bacteria via its readily detectable, characteristic electron paramagnetic resonance (EPR) signals . Endogenously produced dinitrosyl iron complex with thiolate ligands (DNIC) has a critical biological potential; and it can function as a physiologic regulatory factor in a biological system, especially the immune and cardiovascular systems . We have been studying the in vivo behavior and distribution of DNIC to elucidate its physiological roles and pharmacokinetics . In this article, an attempt is made to provide an overview of the history, physiology and in vivo behavior of DNIC. SAR QSAR Environ Res, 2000, 11(2), 149 - 82 Neural networks predict protein folding and structure: artificial intelligence faces biomolecular complexity; Casadio R et al.; In the genomic era DNA sequencing is increasing our knowledge of the molecular structure of genetic codes from bacteria to man at a hyperbolic rate . Billions of nucleotides and millions of aminoacids are already filling the electronic files of the data bases presently available, which contain a tremendous amount of information on the most biologically relevant macromolecules, such as DNA, RNA and proteins . The most urgent problem originates from the need to single out the relevant information amidst a wealth of general features . Intelligent tools are therefore needed to optimise the search . Data mining for sequence analysis in biotechnology has been substantially aided by the development of new powerful methods borrowed from the machine learning approach . In this paper we discuss the application of artificial feedforward neural networks to deal with some fundamental problems tied with the folding process and the structure-function relationship in proteins. AANA J, 1999 Oct, 67(5), 433 - 9 To reuse your circuit: the HME debate; Neft MW et al.; Heat and moisture exchangers (HMEs) have been used for more than 30 years for heat and moisture retention during general anesthesia . Studies about bacteriostatic vs nonbacteriostatic HMEs (BHMEs/NHMEs) have been conducted to assess their role in preventing bacterial transmission to the anesthesia breathing circuit; none have been done on anesthetized patients in the operating room . The present study adds to existing knowledge about the HME's ability to prevent transmission of bacteria, with implications for cost reduction resulting from reuse of anesthesia breathing circuits among patients . The chi 2 test revealed no statistically significant differences between groups in transmission of bacteria from endotracheal tube (ETT) to anesthesia breathing circuit (P = .48) . However, both groups showed statistically significant differences between presence of bacteria in ETTs and anesthesia breathing circuits: Group 1, BHME (P < .005) and group 2, NHME (P < .005) . Neither HME prevented contamination of the machine side of the circuit . These results support not reusing breathing circuits . Of 53 participants in group 2, 28 had positive ETT cultures with 7 showing transmission to anesthesia breathing circuit . Of 46 participants in group 1, 28 had positive ETT cultures with 9 showing transmission to anesthesia breathing circuit. Cell Biol Int, 2000, 24(7), 467 - 73 Replication protein a 32 kDa subunit (RPA p32) binds the SH2 domain of STAT3 and regulates its transcriptional activity; Kim J et al.; STATs (signal transducers and activators of transcription) are tr