Microbiological

J Biol Chem . 2005 Jan 14; {Epub ahead of print}
Evolution of mitochondrial oxa proteins from bacterial YidC: Inherited and acquired functions of a conserved protein insertion machinery; Preuss M et al.; Members of the Oxa1/YidC family are involved in the biogenesis of membrane proteins . In bacteria, YidC catalyzes the insertion and assembly of proteins of the inner membrane . Mitochondria of animals, fungi, and plants harbour two distant homologues of YidC: Oxa1 and Cox18/Oxa2 . Oxa1 plays a pivotal role in the integration of mitochondrial translation products into the inner membrane of mitochondria . It contains a C-terminal ribosome-binding domain which physically interacts with mitochondrial ribosomes to facilitate the cotranslational insertion of nascent membrane proteins . The molecular function of Cox18/Oxa2 is not well understood . Employing a functional complementation approach with mitochondria-targeted versions of YidC we show that YidC is able to functionally replace both Oxa1 and Cox18/Oxa2 . However, to integrate mitochondrial translation products into the inner membrane of mitochondria, the ribosome-binding domain of Oxa1 has to be appended onto YidC . On the contrary, the fusion of the ribosome-binding domain onto YidC prevents its ability to complement COX18 mutants suggesting an indispensable post-translational activity of Cox18/Oxa2 . Our observations suggest that during evolution of mitochondria from their bacterial ancestors the two descendents of YidC functionally segregated in order to perform two distinct activities, one co-translational and one post-translational.

Clin Microbiol Rev, 2005 Jan, 18(1), 195 - 204
Bacterial contamination of blood components; Brecher ME et al.; Blood for transfusion is a potential source of infection by a variety of known and unknown transmissible agents . Over the last 20 years, astounding reductions in the risk of viral infection via allogeneic blood have been achieved . As a result of this success, bacterial contamination of blood products has emerged as the greatest residual source of transfusion-transmitted disease . This paper summarizes the current status of detection, prevention, and elimination of bacteria in blood products for transfusion.

Biochim Biophys Acta, 2005 Jan 18, 1721(1-3), 27 - 36 Epub 2004 Nov 04.
Biosynthesis of lysine in plants: evidence for a variant of the known bacterial pathways; Hudson AO et al.; With the aim of elucidating how plants synthesize lysine, extracts prepared from corn, tobacco, Chlamydomonas and soybean were tested and found to lack detectable amounts of N-alpha-acyl-l,l-diaminopimelate deacylase or N-succinyl-alpha-amino-epsilon-ketopimelate-glutamate aminotransaminase, two key enzymes in the central part of the bacterial pathway for lysine biosynthesis . Corn extracts missing two key enzymes still carried out the overall synthesis of lysine when provided with dihydrodipicolinate . An analysis of available plant DNA sequences was performed to test the veracity of the negative biochemical findings . Orthologs of dihydrodipicolinate reductase and diaminopimelate epimerase (enzymes on each side of the central pathway) were readily found in the Arabidopsis thaliana genome . Orthologs of the known enzymes needed to convert tetrahydrodipicolinate to diaminopimelic acid (DAP) were not detected in Arabidopsis or in the plant DNA sequence databases . The biochemical and reinforcing bioinformatics results provide evidence that plants may use a novel variant of the bacterial pathways for lysine biosynthesis.

Chembiochem . 2005 Jan 13; {Epub ahead of print}
Structure and Biosynthesis of Myxochromides S(1-3) in Stigmatella aurantiaca: Evidence for an Iterative Bacterial Type I Polyketide Synthase and for Module Skipping in Nonribosomal Peptide Biosynthesis; Wenzel SC et al.; The myxobacterium Stigmatella aurantiaca DW4/3-1 harbours an astonishing variety of secondary metabolic gene clusters, at least two of which were found by gene inactivation experiments to be connected to the biosynthesis of previously unknown metabolites . In this study, we elucidate the structures of myxochromides S(1-3), novel cyclic pentapeptide natural products possessing unsaturated polyketide side chains, and identify the corresponding biosynthetic gene locus, made up of six nonribosomal peptide synthetase modules . By analyzing the deduced substrate specificities of the adenylation domains, it is shown that module 4 is most probably skipped during the biosynthetic process . The polyketide synthase MchA harbours only one module and is presumably responsible for the formation of the variable complete polyketide side chains . These data indicate that MchA is responsible for an unusual iterative polyketide chain assembly.

World J Surg . 2005 Jan 6; {Epub ahead of print}
Bacterial Translocation: Not a Clinically Relevant Phenomenon in Colorectal Cancer; Takesue Y et al.; The aim of this study was to identify the risk factors for bacterial translocation and to determine the clinical significance of bacterial translocation in patients with colorectal cancer . Mesenteric lymph node sampling was performed to identify the presence of bacterial translocation in 75 patients with colorectal cancer undergoing laparotomy . Bacterial translocation was identified in 29 patients (39%), with the most common organism being Escherichia coli (31%) . Three factors for bacterial translocation were identified, including a preoperative low peripheral lymphocyte count, metastasis to lymph nodes, and invasion depth (= T3) . Stepwise regression analysis, however, selected only = T3 {odds ratio (OR) 4.0, 95% confidence interval (CI) 1.2-13.5} . Altogether, 35% of patients with bacterial translocation developed septic complications, compared with 20% in patients without bacterial translocation . In the multivariate analysis, bacterial translocation was not an independent risk factor for infection, with an OR of 1.8 (95% CI 0.56-5.96) . Systemic inflammatory response syndrome developed on the first day in 62% of patients with bacterial translocation, compared with 50% of patients without bacterial translocation . Adjusting for the other factors, bacterial translocation was not a significant risk factor in the occurrence of systemic inflammatory response syndrome after surgery (OR 1.1, 95% CI 0.37-3.29) . We concluded that n patients with colorectal cancers bacterial translocation does occur and is increased in patients with deep invasion . However, it appears to be of no clinical significance.

J Microbiol, 2004 Dec, 42(4), 357 - 60
Bacterial aggregates formation after addition of glucose in Lake Baikal water; Spiglazov LP et al.; For determining the process of bacterial aggregation, glucose was added into water from Lake Baikal which had been stored for seven months . In the presence of a higher concentration of glucose, the abundance of single bacteria and aggregates were higher, but the biovolumes of both bacteria were similar . Theses results mean that both free-living and aggregated bacteria have similar maximum sizes and that aggregates are forming with available organic materials . With available organic materials, the biovolume of aggregates becomes larger.

Eur J Gastroenterol Hepatol, 2005 Jan, 17(1), 45 - 51
Intracellular cytokine expression in peritoneal monocyte/macrophages obtained from patients with cirrhosis and presence of bacterial DNA; Frances R et al.; BACKGROUND: The detection of bacterial DNA in serum and ascitic fluid from patients with cirrhosis and ascites is interpreted as molecular evidence of intestinal bacterial translocation and considered sufficient to activate the cellular immune response . In vitro studies on ascitic fluid culture have shown a close relationship between the synthesis of several cytokines and nitric oxide and the presence of bacterial DNA . Since different cell types give rise to cytokines, flow cytometry becomes a powerful tool to discriminate between populations involved in a bacterial challenge . OBJECTIVE: To study the pre-activation status of macrophage/monocyte population ex vivo according to the presence of bacterial DNA . PATIENTS: Patients with cirrhosis and culture-negative, non-neutrocytic ascites, with or without the presence of bacterial DNA in blood and ascitic fluid were studied . METHODS: Flow cytometry analysis of intracellular cytokine expression in monocyte/macrophages from ascitic fluid was performed in basal conditions and after 12 h of cell stimulation adding lypopolysaccharide . RESULTS: Monocyte/macrophages from patients with bacterial DNA showed a significantly higher production of interleukin-6 and tumor necrosis factor alpha in basal conditions than that in cells from patients without the presence of bacterial DNA . The addition of lipopolysaccharide produced a non-significant increment in the expression of these cytokines in patients with the presence of bacterial DNA, while this increment became significant in the other group of patients . CONCLUSIONS: Bacterial translocation in patients with cirrhosis and ascites increases the basal intracellular cytokine expression, reducing its functional reserve capability.

J Environ Qual, 2005 Jan-Feb, 34(1), 217 - 26
Bacterial diversity in selenium reduction of agricultural drainage water amended with rice straw; Siddique T et al.; Bacterial reduction of the Se oxyanions selenate {Se(VI)} and selenite {Se(IV)} to elemental selenium {Se(0)} is an important biological process in removing Se from drainage water . This study was conducted to characterize the molecular diversity of bacterial populations involved in Se reduction of drainage water amended with rice (Oryza sativa L.) straw and also to monitor the bacterial community shifts during the course of the study . Selenate was removed in the drainage water by the bacteria 5 to 6 d after addition of rice straw . Six Se(VI)- and 32 Se(IV)-reducing bacteria were isolated from rice straw containing sterilized drainage water . Three Se(VI)- and two Se(IV)-reducing bacteria were also isolated from the drainage water . Identification of Se(VI)- and Se(IV)-reducing bacteria by 16S rDNA sequence analysis showed a broad phylogenetic diversity in Se-reducing assemblages . Three major phyla (Proteobacteria, Actinobacteria, and Firmicutes) of bacterial domain with numerous classes, orders, and families constituted the Se-reducing bacterial community . We documented changes in the composition of bacterial assemblages in the drainage water amended with rice straw using polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) of 16S rDNA . The Shannon-Weaver index (H') revealed higher bacterial diversity at Day 6 in the sterilized and Day 4 in the nonsterilized drainage water amended with rice straw . The results of this study suggest that rice straw, a good source of carbon and energy, harbors a wide range of bacteria useful in Se reduction and may be used in removing Se from drainage water.

J Am Acad Nurse Pract, 2004 Dec, 16(12), 555 - 60
A descriptive correlational study of bacterial vaginosis in pregnancy and its association with preterm birth: implications for advanced practice nurses; Mascagni JR et al.; PURPOSE: To expand on prior (often contradictory) research implicating maternal infection as a cause of preterm birth, specifically exploring whether bacterial vaginosis (BV) in pregnancy caused preterm birth in a sample of 103 women in a rural Mississippi obstetric-gynecologic clinic . DATA SOURCES: This descriptive correlational study explored the relationship between BV and preterm birth, using retrospective chart data from a purposive sample of 103 women (for a power level of 95%) from one rural obstetric-gynecologic clinic . CONCLUSIONS: Contrary to the majority of published research, this study did not find a positive correlation between BV and preterm birth . This unexpected result raises questions, particularly given that the preponderance (86%) of women who tested positive for BV during their pregnancy were African American, a population in which both BV and preterm birth are more prevalent . IMPLICATIONS FOR PRACTICE: Whether to screen for BV in pregnancy is a clinically important question not only in terms of the health of mother and child but also in terms of responsible use of resources . Clear findings supporting beneficial health results for screening would dictate screening regardless of the cost . But research continues to lack consensus on the efficacy of BV screening during pregnancy in preventing adverse pregnancy outcomes . In this study, as in some of the literature, the risk of preterm birth did not correlate positively with BV during pregnancy . In the absence of that correlation, cost gains importance . Nurse practitioners (NPs) must use resources wisely, including time, laboratory tests, and medications . Although some specialists recommend screening or treating all pregnant patients for BV, the current practice of not screening or treating all pregnant patients seems warranted until definitive findings establish a conclusive correlation between BV and preterm birth.

Clin Gastroenterol Hepatol, 2005 Jan, 3(1), 85 - 9
The role of likelihood ratio in clinical diagnosis: Applicability in the setting of spontaneous bacterial peritonitis; Sierra F et al.; Despite imperfect clinical information and uncertainty about clinical course and outcome, the clinician's main task is to make reasonable decisions about patient care . The clinical history and physical examination typically provide information that is useful for making a diagnosis; however, we still rely on laboratory and radiologic tests to confirm a diagnosis in most cases . Understanding the operative characteristic of a test is of key importance because it can change the probability that a patient has a disease before the result of a test is known . This operative characteristic, better known as the likelihood ratio (LR), is a global assessment of the information provided by a test . The LR allows calculating the odds that a patient has a disease after a test is performed . In this article, we explain the meaning of the LR, how it works, and the applicability of this tool in the setting of a challenging scenario in clinical practice, spontaneous bacterial peritonitis.

J Mol Biol, 2005 Feb 4, 345(5), 937 - 55 Epub 2004 Dec 16.
Conformational analysis of invariant Peptide sequences in bacterial genomes; Prakash T et al.; The functional significance of evolutionarily conserved motifs/patterns of short regions in proteins is well documented . Although a large number of sequences are conserved, only a small fraction of these are invariant across several organisms . Here, we have examined the structural features of the functionally important peptide sequences, which have been found invariant across diverse bacterial genera . Ramachandran angles (varphi,psi) have been used to analyze the conformation, folding patterns and geometrical location (buried/exposed) of these invariant peptides in different crystal structures harboring these sequences . The analysis indicates that the peptides preferred a single conformation in different protein structures, with the exception of only a few longer peptides that exhibited some conformational variability . In addition, it is noticed that the variability of conformation occurs mainly due to flipping of peptide units about the virtual C(alpha)cdots, three dots, centeredC(alpha) bond . However, for a given invariant peptide, the folding patterns are found to be similar in almost all the cases . Over and above, such peptides are found to be buried in the protein core . Thus, we can safely conclude that these invariant peptides are structurally important for the proteins, since they acquire unique structures across different proteins and can act as structural determinants (SD) of the proteins . The location of these SD peptides on the protein chain indicated that most of them are clustered towards the N-terminal and middle region of the protein with the C-terminal region exhibiting low preference . Another feature that emerges out of this study is that some of these SD peptides can also play the roles of "fold boundaries" or "hinge nucleus" in the protein structure . The study indicates that these SD peptides may act as chain-reversal signatures, guiding the proteins to adopt appropriate folds . In some cases the invariant signature peptides may also act as folding nuclei (FN) of the proteins.

Environ Microbiol, 2005 Jan, 7(1), 78 - 87
Assessing terminal restriction fragment length polymorphism suitability for the description of bacterial community structure and dynamics in hydrocarbon-polluted marine environments; Denaro R et al.; Summary The distribution of bacterial communities terminal restriction fragment length polymorphism (T-RFLP) fingerprint patterns was evaluated at three proximal hydrocarbon-contaminated sites located within the harbour of Messina . In order to analyse the short-term variability of the individual terminal restriction fragment (T-RF) patterns, water samples were collected at the three sites on three occasions within 3 months (T(0), T(90) and T(91)) . Four sample sizes, from 50 to 1000 ml for each collected sample, were analysed separately (36 total analysed samples) to evaluate the relationship between the sample size and the bacterial diversity estimates . The dominant T-RF groups mostly belonged to signatures of putative hydrocarbon-degrading bacteria, as revealed by the virtual analysis of the obtained bands . In order to test whether significant differences were occurring between the analysed samples, the Kruskal-Wallis non-parametric test was applied to the T-RF data set . Neither significant influence of the sample size nor short spatial variability within the three sampled sites was detected for each sampling time . On the contrary, significant temporal changes in the diversity of the bacterial communities were observed . These results were confirmed by the non-metric multidimensional scales (nMDS) analysis of the whole set of samples, which indicated three main groups corresponding to the three different sampling times . In summary, the T-RFLP technique, although a polymerase chain reaction-based method, proved to be a suitable technique for monitoring polluted marine environments, typically characterized by low diversity and high relative abundances of a few dominant groups.

J Asthma, 2004, 41(8), 863 - 8
Atypical bacterial pneumonia and asthma risk; Sutherland ER et al.; The role of respiratory infections in asthma is poorly understood . Atypical bacteria Mycoplasma pneumoniae and Chlamydia pneumoniae are present in the lower airways of approximately 50% of asthmatics . This study tested the hypothesis that early life community-acquired pneumonia caused by Mycoplasma pneumoniae or Chlamydia pneumoniae is associated with increased asthma prevalence . Thirty-five subjects with a history of community-acquired pneumonia (22 due to atypical bacteria, 13 due to nonatypical pathogens) were evaluated by questionnaire 7-9 years after the episode of pneumonia . Subjects with a history of either typical or atypical pneumonia demonstrated increased asthma prevalence . Current or past asthma prevalence was 55% in subjects with atypical bacterial pneumonia and 61.5% in subjects with nonatypical bacterial pneumonia . Significant between-group differences were not demonstrated with regard to asthma prevalence (risk ratio=0.89; 95% confidence interval=0.49-1.61), current bronchodilator use {1.18 (0.44-3.17)}, and family history of atopy {1.18 (0.73-1.91)}, or asthma {1.63 (0.68-3.88)} . These data suggest that atypical bacterial pneumonia confers a risk of asthma similar to that seen with nonatypical bacterial pneumonia . Prospective studies are warranted to more fully evaluate the importance of atypical bacterial pneumonia as an asthma risk factor.

Eur J Clin Invest, 2005 Jan, 35(1), 13 - 6
Identification of different bacterial DNAs in human coronary arteries; Lehtiniemi J et al.; Abstract Background Various studies have suggested a link between infection, atherosclerosis and coronary artery disease . We studied whether bacterial DNA is present in coronary specimens obtained from left anterior descending coronary arteries of subjects having sudden deaths of cardiovascular and other causes, as verified by an autopsy . Materials and methods Coronary specimens were obtained from five subjects who died of sudden coronary causes and five controls . Broad-range 16-s rDNA PCR (Br-PCR) amplification, cloning and sequencing were used to detect bacterial rDNA . Results Bacterial rDNA sequences of oral pathogens were detected from the coronary samples in all cases regardless of the cause of death . Conclusions Br-PCR is a powerful method to detect bacterial rDNA . By this method we were able to detect wide palette of oral bacteria from coronary tissues . Our findings suggest that atheromas may act as mechanical sieves collecting bacteria from the circulation . Eur J Clin Invest 2005; 35 (1): 13-16.

J Antibiot (Tokyo), 2004 Oct, 57(10), 639 - 46
A-503083 A, B, E and F, novel inhibitors of bacterial translocase I, produced by Streptomyces sp . SANK 62799; Muramatsu Y et al.; Novel nucleoside antibiotics were isolated from the cultured broth of the strain classified as Streptomyces sp . SANK 62799 . The strain produced four novel capuramycin derivatives designated as A-503083 A, B, E and F . Their structures were elucidated as 2'-O-carbamoyl derivatives of A-500359 A, B (capuramycin), E and F, respectively . A-503083 A, B, E and F inhibited bacterial phospho-N-acetylmuramyl-pentapeptide-translocase (translocase I: EC 2.7.8.13) with IC50 values of 0.024, 0.038, 0.135 and 17.9 microM, respectively.

Res Microbiol, 2005 Jan-Feb, 156(1), 1 - 6
Bacterial conjugation: a potential tool for genomic engineering; Llosa M et al.; Bacterial conjugation is a mechanism for horizontal DNA transfer with potential for universal DNA delivery . The conjugal machinery can be separated into three functional modules: the relaxosome, the coupling protein, and a type IV protein secretion system . Module interchangeability among different conjugative systems opens up the possibility of "a la carte" engineering of DNA delivery into virtually any cell type.

Rev Med Chil, 2004 Oct, 132(10), 1217 - 20
{Malignant middle cerebral artery territory infarct in one patient with bacterial meningitis}; Lopez MG et al.; The mortality of acute bacterial meningitis (BM) has remained stable in the last decades in spite of the use of new antibiotics, probably due to vascular complications . We report a 68-year-old woman with BM who had a malignant infarction of left middle cerebral artery territory 72 hours after admission to the hospital . The patient experienced a bad evolution and died four days after admission . The arterial involvement in patients with BM is explained by vasospasm of large arteries and vasculitis of small arteries . The medical treatment of a malignant middle cerebral artery infarct has a high mortality.

Plant Mol Biol, 2004 Nov, 56(4), 555 - 61
Bacterial artificial chromosome (BAC) library resource for positional cloning of pest and disease resistance genes in cassava (Manihot esculenta Crantz); Tomkins J et al.; Pest and disease problems are important constraints of cassava production and host plant resistance is the most efficient method of combating them . Breeding for host plant resistance is considerably slowed down by the crop's biological constraints of a long growth cycle, high levels of heterozygosity and a large genetic load . More efficient methods such as gene cloning and transgenesis are required to deploy resistance genes . To facilitate the cloning of resistance genes, bacterial artificial chromosome (BAC) library resources have been developed for cassava . Two libraries were constructed from the cassava clones, TMS 30001, resistant to the cassava mosaic disease (CMD) and the cassava bacterial blight (CBB), and MECU72, resistant to cassava white fly . The TMS30001 library has 55 296 clones with an insert size range of 40-150 kb with an average of 80 kb, while the MECU72 library consists of 92 160 clones and an insert size range of 25-250 kb average of 93 kb . Based on a genome size of 772 Mb, the TMS30001 and MECU72 libraries have a 5 and 11.3 haploid genome equivalents and a 95 and 99 chance of finding any sequence, respectively . To demonstrate the potential of the libraries, the TMS30001 library was screened by southern hybridization using a cassava analog (CBB1) of the Xa21 gene from rice that maps to a region containing a QTL for resistance to CBB as probe . Five BAC clones that hybridized to CBB1 were isolated and a Hind III fingerprint revealed 2-3 copies of the gene in individual BAC clones . A larger scale analysis of resistance gene analogs (RGAs) in cassava has also been conducted in order to understand the number and organization of RGAs . To scan for gene and repeat DNA content in the libraries, end-sequencing was performed on 2301 clones from the MECU72 library . A total of 1705 unique sequences were obtained with an average size of 715 bp . Database homology searches using BLAST revealed that 458 sequences had significant homology with known proteins and 321 with transposable elements . The use of the library in positional cloning of pest and disease resistance genes is discussed.

Mol Cell, 2005 Jan 7, 17(1), 113 - 20
Suppression of Homologous and Homeologous Recombination by the Bacterial MutS2 Protein; Pinto AV et al.; In addition to their role in DNA repair, recombination events are associated with processes aimed at providing the genetic variability needed for adaptation and evolution of a population . In bacteria, recombination is involved in the appearance of new variants by allowing the incorporation of exogenous DNA or the reshuffling of endogenous sequences . Here we show that HpMutS2, a protein belonging to the MutS2 family in Helicobacter pylori, is not involved in mismatch repair but inhibits homologous and homeologous recombination . Disruption of HpmutS2 leads to an increased efficiency of exogenous DNA incorporation . HpMutS2 has a selective affinity for DNA structures mimicking recombination intermediates with no specificity for homoduplex DNA or mismatches . The purified protein has an ATPase activity stimulated by the same DNA structures . Finally, we show that HpMutS2 inhibits DNA strand exchange reactions in vitro . Thus, MutS2 proteins are candidates for controlling recombination and therefore genetic diversity in bacteria.

Anal Chem, 2005 Jan 1, 77(1), 327 - 34
Microfluidic immunoassay for bacterial toxins with supported phospholipid bilayer membranes on poly(dimethylsiloxane); Phillips KS et al.; We report a heterogeneous immunoassay for cholera toxin (CT) using supported bilayer membranes (SBMs) in a poly(dimethylsiloxane) (PDMS) microfluidic device . Phosphatidylcholine membranes assembled on plasma-oxidized PDMS by vesicle fusion bring about favorable surface properties, such as improved wettability and protein resistance . Contact angle measurements show that the lipid membranes can preserve hydrophilic surfaces for hours, whereas untreated substrates rapidly undergo hydrophobic recovery . Fluorescence recovery after photobleaching performed in situ reveals that the membranes have relatively high lateral mobility . Experimental data-fitting to theoretical models yields diffusion coefficients of 1.8 +/- 0.7 microm(2)/s on PDMS and 3.4 +/- 0.8 microm(2)/s on glass . Fluorescence studies utilizing tagged proteins show that SBMs reduce nonspecific adsorption of avidin and BSA on PDMS by 2-3 orders of magnitude, as compared to that on plasma oxidized surfaces . SBMs and their protein-resistant properties are not significantly affected by long flow times, indicating good membrane stability . These studies increase our understanding of the relationship between molecular level interactions and membrane properties, allowing for development of a rapid heterogeneous immunoassay for CT in PDMS microchips with cell surface receptor molecules . Using optimized sample injection and buffer washing conditions, microfluidic immunoassay of CT is complete within 25 min, and a dynamic range over 3 orders of magnitude with a detection limit of 8 fmol of toxin is achieved.

Anal Biochem, 2005 Jan 15, 336(2), 300 - 4
Quantitative nonisotopic nitrocellulose filter binding assays: bacterial manganese superoxide dismutase-DNA interactions; Czerwinski JD et al.; Nitrocellulose filter binding assays (NCFBAs) have been used for many years to qualitatively and quantitatively determine protein-nucleic acid affinities . While this technique can be robust thermodynamically and fairly simple to perform, the requirement of radiolabeled nucleic acids (typically (32)P) has several major drawbacks . Some disadvantages are the short half-life of (32)P, the inherent safety concerns, and the cost of working with radioisotopes . Another drawback is that over time the beta emissions cause fragmentation of the nucleic acids . We have modified standard NCFBAs by developing a quantitative nonisotopic chemiluminescent method using biotin-labeled DNA and a dual-filter format . The biotin tag is detected on both nitrocellulose and positively charged nylon membranes by conventional streptavidin-conjugated alkaline phosphatase recognition systems . Quantitation of the photon emissions is simplified by use of a cooled charge-coupled device camera, although exposure to X-ray film and quantitation by densitometry could also be employed . The binding affinity of bacterial manganese superoxide dismutase to nonsequence-specific DNA has been quantitated previously by standard NCFBAs . We have replicated parts of a published binding study using identical solution conditions and the nonisotopic method that we have developed . We provide quantitative agreement between the isotopic and the nonisotopic methods.

Biosci Biotechnol Biochem, 2004 Dec, 68(12), 2451 - 6
Analysis of Bacterial Glucose Dehydrogenase Homologs from Thermoacidophilic Archaeon Thermoplasma acidophilum: Finding and Characterization of Aldohexose Dehydrogenase; Nishiya Y et al.; The NADP(+)-preferring glucose dehydrogenase from thermoacidophilic archaeon Thermoplasma acidophilum has been characterized, and its crystal structure has been determined (Structure, 2:385-393, 1994) . Its sequence and structure are not homologous to bacterial NAD(P)(+)-dependent glucose dehydrogenases, and its molecular weight is also quite defferent . On the other hand, three functionally unknown genes with homologies to bacterial NAD(P)(+)-dependent glucose dehydrogenases have been sequenced as part of the T . acidophilum genome project (gene names: Ta0191, Ta0747, and Ta0754 respectively) . We expressed two genes of three, Ta0191 and Ta0754, in Escherichia coli, and purified the gene products to homogeneity . Dehydrogenase activities were thereby detected from the purified proteins . The Ta0754 gene product exhibited aldohexose dehydrogenase activity, and the Ta0191 gene product exhibited weak 2-deoxyglucose dehydrogenase activity . No aldohexose dehydrogenase gene has been isolated, while the enzyme was reported in 1968 . This is the first report of the gene and primary structure . The purified Ta0754 gene product, designated AldT, was characterized . The enzyme AldT effectively catalyzed the oxidation of various aldohexoses, especially D-mannose . Lower activities on D-2-deoxyglucose, D-xylose, D-glucose, and D-fucose were detected although no activities were shown on other aldohexoses or additional sugars . As a cofactor, NAD(+) was much more suitable for the activity than NADP(+) . The NAD(+)-preferring dehydrogenase most effectively reacting to D-mannose is for the first time . AldT was most active at pH 10 and above 70 degrees C, and completely stable up to 60 degrees C after incubation for 15 min . Other enzymatic properties were also investigated.

J Biol Chem . 2004 Dec 23; {Epub ahead of print}
The bacterial ATPase SecA functions as a monomer In protein translocation; Or E et al.; The ATPase SecA drives the post-translational translocation of proteins through the SecY channel in the bacterial inner membrane . SecA is a dimer which can dissociate into monomers under certain conditions . To address the functional importance of the monomeric state, we generated an E . coli SecA mutant that is almost completely monomeric (>99%), consistent with predictions from the crystal structure of B . subtilis SecA . In vitro, the monomeric derivative retained significant activity in various assays and in vivo, it sustained 85% of the growth rate of wild type cells and reduced the accumulation of precursor proteins in the cytoplasm . Disulfide cross-linking in intact cells showed that mutant SecA is monomeric and that even its parental dimeric form is dissociated . Our results suggest that SecA functions as a monomer during protein translocation in vivo.

Infect Immun, 2005 Jan, 73(1), 657 - 60
Relative contributions of innate and acquired host responses to bacterial control and arthritis development in Lyme disease; Wang X et al.; TLR2(-/-)/scid double-mutant mice were infected with B . burgdorferi to assess the relative importance of acquired and innate host defenses . Although spirochete levels at 4 weeks were lower in TLR2(-/-) mice than in TLR2(-/-)/scid mice, the increased arthritis severity of TLR2 (Toll-like receptor 2)-deficient mice was reduced by the presence of the scid mutation.

Surgery, 2005 Jan, 137(1), 85 - 91
Apoptosis inhibition plays a greater role than necrosis inhibition in decreasing bacterial translocation in experimental intestinal transplantation; Azuara D et al.; BACKGROUND: During small-bowel transplantation, necrosis and apoptosis are involved in the destruction of intestinal epithelial cells . This study was conducted to assess which mode of cell death plays a greater role as a trigger of the bacterial translocation (BT) associated with intestinal transplantation . METHODS: The following experimental groups were studied: sham, Tx (intestinal transplantation), Tx + poly (ADP-ribose) synthetase (PARS) inhibitor 3-aminobenzamide (3-AB), and Tx + caspase inhibitor Z-VAD-fmk . Histological analysis, caspase-3 activity, DNA fragmentation, and BT were measured in tissue samples after transplantation . RESULTS: During intestinal transplantation, apoptosis and necrosis both increased, showing graft injury and high levels of BT . Rats treated with 3-AB showed histological protection of the transplanted graft and a tendency toward lower BT despite the existence of high apoptosis levels . The rats treated with Z-VAD showed histological protection of the transplanted graft and decreased levels of caspase-3 and DNA fragmentation . The Tx + Z-VAD group showed the lowest levels of BT in all tissues . CONCLUSIONS: In small intestinal transplantation, both apoptosis and cell necrosis give rise to histological injury and BT . Apoptosis inhibition and necrosis inhibition treatments protect intestinal grafts from ischemia/reperfusion injury; Z-VAD supplementation has a greater effect on BT prevention than does administration of the PARS inhibitor 3-AB.

J Biol Chem . 2004 Dec 21; {Epub ahead of print}
Two heme binding sites are involved in the regulated degradation of the bacterial iron response regulator (Irr) protein; Yang J et al.; The iron response regulator (Irr) protein from Bradyrhizobium japonicum is a conditionally stable protein that degrades in response to cellular iron availability . This turnover is heme-dependent, and rapid degradation involves heme binding to a heme regulatory motif (HRM) of Irr . Here, we show that Irr confers iron-dependent instability on glutathione S-transferase (GST) when fused to it . Analysis of Irr-GST derivatives with C-terminal truncations of Irr implicated a second region necessary for degradation other than the HRM, and showed that the HRM was not sufficient to confer instability on GST . The HRM-defective mutant IrrC29A degraded in the presence of iron, but much more slowly than the wild type protein . This slow turnover was heme-dependent as discerned by the stability of Irr in a heme-defective mutant strain . Whereas the HRM of purified recombinant Irr binds ferric (oxidized) heme, a second site that binds ferrous (reduced) heme was identified based on spectral analysis of truncation and substitution mutants . A mutant in which histidines 117 to 119 were changed to alanines severely diminished ferrous, but not ferric, heme binding . Introduction of these substitutions in an Irr-GST fusion stabilized the protein in vivo in the presence of iron . We conclude that normal iron-dependent Irr degradation involves two heme binding sites, and that both redox states of heme are required for rapid turnover.

Bioinformatics . 2004 Dec 21; {Epub ahead of print}
Dynamic network reconstruction from gene expression data applied to immune response during bacterial infection; Guthke R et al.; MOTIVATION: The immune response to bacterial infection represents a complex network of dynamic gene and protein interactions . We present an optimized reverse engineering strategy aimed at a reconstruction of this kind of interaction networks . The proposed approach is based on both, microarray data and available biological knowledge . RESULTS: The main kinetics of the immune response were identified by fuzzy clustering of gene expression profiles (time series) . The number of clusters was optimized using various evaluation criteria . For each cluster a representative gene with a high fuzzy-membership was chosen in accordance with available physiological knowledge . Then hypothetical network structures were identified by seeking systems of ordinary differential equations, whose simulated kinetics could fit the gene expression profiles of the cluster-representative genes . For the construction of hypothetical network structures Singular Value Decomposition (SVD) based methods and a here newly introduced heuristic Network Generation Method were compared . It turned out that the proposed novel method could find sparser networks and gave better fits to the experimental data.

Eur J Neurol, 2005 Jan, 12(1), 67 - 9
Fulminant acute disseminated encephalomyelitis mimicking acute bacterial menigoencephalitis; Harloff A et al.; Most patients with acute disseminated encephalomyelitis (ADEM) recover quickly under corticosteroid treatment and have a favourable long-term prognosis . We report on a young woman with acute onset of an extensive and solitary white-matter lesion in the left hemisphere . Fever, high pleocytosis and elevated protein in cerebrospinal fluid initially suggested bacterial meningoencephalitis . The patient died from brain herniation despite maximal conservative therapy . Histological changes in necropsy were consistent with the diagnosis ADEM . Treatment options of fulminant ADEM are discussed.

Lett Appl Microbiol, 2005, 40(1), 12 - 8
The influence of environmental adaptation on bacterial genome structure; Fadiel A et al.; Abstract a . fadiel, s . lithwick and f . naftolin . 2004.Aims: Researchers have long been puzzled by the diversity of life . Now that the complete genomic sequence of many organisms has been determined, it is possible to evaluate the impact of organismal variation on sequence structure or vice versa . The aim of this investigation was to explore genomic changes mandated by organismal adaptation to its ecological niches . Methods and Results: Coding sequences from three phylogenetically related bacterial species namely Mycoplasma genitalium, M . pneumoniae and Ureaplasma urealyticum were subject to in depth sequence analyses . M . genitalium and M . pneumoniae both belong to the genus Mycoplasma while U . urealyticum is a member of the genus Ureaplasma . However, M . genitalium and U . urealyticum are urogenital pathogens while M . pneumoniae is a respiratory pathogen . Complete transcriptomes were downloaded from NCBI for each species, and were subject to in silico investigation using in-house software, and public sequence analysis tools . Clear similarities in transcriptome structure were identified among the functionally similar species M . genitalium and U . urealyticum while no such relationship was identified among the phylogenetically related species M . genitalium and M . pneumoniae . Conclusions: It is plausible to conclude that, in these bacterial species, environmental stimuli might be more influential in shaping sequence signatures than phylogenetic relationships . Significance and Impact of the Study: This study suggests that molecular signatures within the transcriptomes of the species examined are likely to be a product of evolutionary adaptation to diverse environmental ecological stimuli, and not a result of common phylogeny.

J Comp Neurol, 2005 Feb 7, 482(2), 123 - 41
Glycinergic neurons expressing enhanced green fluorescent protein in bacterial artificial chromosome transgenic mice; Zeilhofer HU et al.; Although glycine is a major inhibitory transmitter in the mammalian CNS, the role of glycinergic neurons in defined neuronal circuits remains ill defined . This is due in part to difficulties in identifying these cells in living slice preparations for electrophysiological recordings and visualizing their axonal projections . To facilitate the morphological and functional analysis of glycinergic neurons, we generated bacterial artificial chromosome (BAC) transgenic mice, which specifically express enhanced green fluorescent protein (EGFP) under the control of the promotor of the glycine transporter (GlyT) 2 gene, which is a reliable marker for glycinergic neurons . Neurons expressing GlyT2-EGFP were intensely fluorescent, and their dendrites and axons could be visualized in great detail . Numerous positive neurons were detected in the spinal cord, brainstem, and cerebellum . The hypothalamus, intralaminar nuclei of the thalamus, and basal forebrain also received a dense GlyT2-EGFP innervation, whereas in the olfactory bulb, striatum, neocortex, hippocampus, and amygdala positive fibers were much less abundant . No GlyT2-EGFP-positive cell bodies were seen in the forebrain . On the subcellular level, GlyT2-EGFP fluorescence was colocalized extensively with glycine immunoreactivity in somata and dendrites and with both glycine and GlyT2 immunoreactivity in axon terminals, as shown by triple staining at all levels of the neuraxis, confirming the selective expression of the transgene in glycinergic neurons . In slice preparations of the spinal cord, no difference between the functional properties of EGFP-positive and negative neurons could be detected, confirming the utility of visually identifying glycinergic neurons to investigate their functional role in electrophysiological studies . J . Comp . Neurol . 482:123-141, 2005 . (c) 2004 Wiley-Liss, Inc.

Biochemistry, 2004 Dec 28, 43(51), 16487 - 96
Carotenoid-induced cooperative formation of bacterial photosynthetic LH1 complex; Fiedor L et al.; A simple reconstitution technique has been developed and then applied to prepare a series of light-harvesting antenna 1 (LH1) complexes with a programmed carotenoid composition, not available from native photosynthetic membranes . The complexes were reconstituted with different C(40) carotenoids, having two structural parameters variable: the functional side groups and the number of conjugated C-C double bonds, systematically increasing from 9 to 13 . The complexes, differing only in the type of carotenoid, bound to an otherwise identical bacteriochlorophyll-polypeptide matrix, can serve as a unique model system in which the relationship between the carotenoid character and the functioning of pigment-protein complexes can be investigated . The reconstituted LH1 complexes resemble the native antenna, isolated from wild-type Rhodospirillum rubrum, but their coloration is entirely determined by carotenoid . Along with the increase in its conjugation size, the carotenoid absorption transitions gradually shift to the red . Thus, the extension of the conjugation size of the antenna carotenoids provides a mechanism for the spectral tuning of light harvesting in the visible part of the spectrum . The carotenoids in the reconstitution system promote the LH1 formation and seem to bind and transfer the excitation energy specifically only to a species with characteristically red-shifted absorption and emission maxima, apparently, due to a cooperative effect . Monitoring the LH1 formation by steady-state absorption and fluorescence spectroscopies reveals that in the presence of carotenoids it proceeds without spectrally resolved intermediates, leading directly to B880 . The effect of the carotenoid is enhanced when the pigment contains the hydroxy or methoxy side groups, implying that, in parallel to hydrophobic interactions and pi-pi stacking, other interactions are also involved in the formation and stabilization of LH1.

J Infect Dis, 2005 Jan 15, 191(2), 299 - 306 Epub 2004 Dec 09.
16alpha-Bromoepiandrosterone restores T helper cell type 1 activity and accelerates chemotherapy-induced bacterial clearance in a model of progressive pulmonary tuberculosis; Hernandez-Pando R et al.; BALB/c mice with pulmonary tuberculosis develop a T helper cell type 1 response that peaks at 3 weeks, temporarily controlling bacterial growth . Then bacterial proliferation recommences, accompanied by increasing interleukin (IL)-4 levels and decreasing interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and inducible nitric oxide synthase (iNOS) levels . These changes mimic those in the human disease . In a previous study, administration of dehydroepiandrosterone (DHEA) beginning on day 60 after infection reversed these changes and protected the mice . However, DHEA is suboptimal for human use, partly because it is readily metabolized into sex steroids . 16alpha-Bromoepiandrosterone (EpiBr; 16alpha -bromo-5alpha -androstan-3beta-ol-17-one) is a synthetic adrenal steroid derivative that does not enter sex steroid pathways . In the present study, when tuberculous BALB/c mice were treated with EpiBr 3 times/week beginning on day 60, inhibition of bacterial proliferation and increased expression of TNF-alpha, IFN-gamma, and iNOS were observed, although decreased expression of IL-4 was also observed . Moreover, when given as an adjunct to conventional chemotherapy, EpiBr enhanced bacterial clearance . Trials for the use of EpiBr in the treatment of human tuberculosis are now justified.

Nucleic Acids Res, 2005 Jan 1, 33 Database Issue, D325 - 8
VFDB: a reference database for bacterial virulence factors; Chen L et al.; Bacterial pathogens continue to impose a major threat to public health worldwide in the 21st century . Intensified studies on bacterial pathogenesis have greatly expanded our knowledge about the mechanisms of the disease processes at the molecular level over the last decades . To facilitate future research, it becomes necessary to form a database collectively presenting the virulence factors (VFs) of various medical significant bacterial pathogens . The aim of virulence factor database (VFDB) is to provide such a source for scientists to rapidly access to current knowledge about VFs from various bacterial pathogens . VFDB is comprehensive and user-friendly . One can search VFDB by browsing each genus or by typing keywords . Furthermore, a BLAST search tool against all known VF-related genes is also available . VFDB provides a unified gateway to store, search, retrieve and update information about VFs from various bacterial pathogens.

Pediatr Neurol, 2005 Jan, 32(1), 72 - 74
Diagnosis of bacterial cerebellitis: Diffusion imaging and proton magnetic resonance spectroscopy; Jaggi RS et al.; Diffusion-weighted imaging and in vivo proton magnetic resonance spectroscopy ((1)H magnetic resonance spectroscopy) have demonstrated great potential in differentiating intracranial lesions of various pathologies . This report describes a case of a 12-year-old child with cerebellitis and subdural empyema that manifested presence of succinate, acetate, lactate, and amino acids on in vivo (1)H magnetic resonance spectroscopy from a large area of restricted diffusion in the vermis on diffusion-weighted imaging, a finding specific for bacteria-induced infection . The child made a complete clinical and imaging recovery on conservative management.

J Biotechnol, 2005 Jan 12, 115(1), 11 - 21
Electronic microarray analysis of 16S rDNA amplicons for bacterial detection; Barlaan EA et al.; Electronic microarray technology is a potential alternative in bacterial detection and identification . However, conditions for bacterial detection by electronic microarray need optimization . Using the NanoChip electronic microarray, we investigated eight marine bacterial species . Based on the 16S rDNA sequences of these species, we constructed primers, reporter probes, and species-specific capture probes . We carried out two separate analyses for longer (533bp) and shorter (350 and 200bp) amplified products (amplicons) . To detect simultaneously the hybridization signals for the 350- and 200-bp amplicons, we designed a common reporter probe from an overlapping sequence within both fragments . We developed methods to optimize detection of hybridization signals for processing the DNA chips . A matrix analysis was performed for different bacterial species and complementary capture probes on electronic microarrays . Results showed that, when using the longer amplicon, not all bacterial targets hybridized with the complementary capture probes, which was characterized by the presence of false-positive signals . However, with the shorter amplicons, all bacterial species were correctly and completely detected using the constructed complementary capture probes.

Clin Exp Immunol, 2005 Jan, 139(1), 43 - 7
Influence of age and duration of infection on bacterial load and immune responses to Helicobacter pylori infection in a murine model; Minoura T et al.; Summary Using a murine model, we previously showed that Helicobacter pylori infects and colonizes offspring via maternal transmission during the nursing period . The aim of this study was to investigate the influence of age and duration of infection on inflammatory and immune responses to H . pylori in infant and adult mice . During the breast-feeding period, the number of bacteria was significantly suppressed in 1-week-old mice infected with H . pylori at an early stage of nursing, compared with adult mice, suggesting that breast-milk induces such low colonization . In addition, these mice had weaker gastric inflammation, especially Th1 cytokine and humoral responses than in mice infected with H . pylori after weaning in spite of elevated levels of Th1 cytokines . Although infant mice showed low inflammatory responses against H . pylori, they produced H . pylori-specific antibodies following vaccination with oral or parenteral adjuvant . Our results suggest the importance of age at the time of primary infection on bacterial load, gastric inflammation and humoral responses in a murine model of H . pylori infection.

Ginekol Pol, 2004 Sep, 75(9), 733 - 40
{Bacterial vaginosis}; Ostaszewska-Puchalska I et al.; Bacterial vaginosis (BV) is one of the most common lower genital tract infections among women of childbearing age . This paper is a survey of literature data concerning epidemiology, pathogenesis, clinical and laboratory diagnostic criteria of this clinical syndrome.

FEMS Microbiol Lett, 2004 Dec 15, 241(2), 129 - 134
Displaying the relatedness among isolates of bacterial species - the eBURST approach; Spratt BG et al.; Determining the most appropriate way to represent the relationships between bacterial isolates is complicated by the differing rates of recombination within species . In many cases, a bifurcating tree can be positively misleading . The recently described program eBURST can be used with multilocus data to define groups or clonal complexes of related isolates derived from a common ancestor, the patterns of descent linking them together, and the ancestral genotype . eBURST has recently been extensively updated to include additional tools for exploring the relationships between isolates . We discuss the advantages of this approach and describe its use to explore patterns of descent within clonal complexes identified using multilocus sequence typing.

Mol Plant Microbe Interact, 2004 Dec, 17(12), 1376 - 84
Relationship between avirulence gene (avrA) diversity in Ralstonia solanacearum and bacterial wilt incidence; Robertson AE et al.; Bacterial wilt, caused by Ralstonia solanacearum, is a serious disease of tobacco in North and South Carolina . In contrast, the disease rarely occurs on tobacco in Georgia and Florida, although bacterial wilt is a common problem on tomato . We investigated whether this difference in disease incidence could be explained by qualitative characteristics of avirulence gene avrA in the R . solanacearum population in the southeastern United States . Sequence analysis established that wild-type avrA has a 792-bp open reading frame . Polymerase chain reaction (PCR) amplification of avrA from 139 R . solanacearum strains generated either 792-bp or approximately 960-bp DNA fragments . Strains that elicited a hypersensitive reaction (HR) on tobacco contained the 792-bp allele, and were pathogenic on tomato and avirulent on tobacco . All HR-negative strains generated a approximately 960-bp DNA fragment, and wilted both tomato and tobacco . The DNA sequence of avrA in six HR-negative strains revealed the presence of one of two putative miniature inverted-repeat transposable elements (MITEs): a 152-bp MITE between nucleotides 542 and 543, or a 170-bp MITE between nucleotides 461 and 462 or 574 and 575 . Southern analysis suggested that the 170-bp MITE is unique to strains from the southeastern United States and the Caribbean . Mutated avrA alleles were present in strains from 96 and 75% of North and South Carolina sites, respectively, and only in 13 and 0% of the sites in Georgia and Florida, respectively . Introduction of the wildtype allele on a plasmid into four HR-negative strains reduced their virulence on both tobacco and tomato . Inactivation of avrA in an HR-positive, avirulent strain, resulted in a mutant that was weakly virulent on tobacco . Thus, the incidence of bacterial wilt of tobacco in the southeastern United States is partially explained by which avrA allele dominates the local R . solanacearum population.

Alcohol, 2004 Jul, 33(3), 199 - 208
Impaired intestinal immunity and barrier function: a cause for enhanced bacterial translocation in alcohol intoxication and burn injury; Choudhry MA et al.; Alcohol intoxication is being recognized increasingly as the major factor in pathogenesis after burn injury . Findings from multiple studies support the suggestion that, in comparison with burn-injured patients who sustained injury in the absence of alcohol intoxication, burn-injured patients who sustained injury under the influence of alcohol exhibit higher rates of infection and are more likely to die . Thus, infection becomes the primary cause of death in burn-injured patients . Because the intestine is considered to be a major source of bacteria, studies in experimental animals have been designed to examine whether alcohol intoxication before burn injury enhances bacterial translocation from the intestine . Results of these studies have shown a several-fold increase in bacterial translocation from the intestine in the group of animals receiving combined insult of alcohol intoxication and burn injury compared with findings for the groups receiving either insult alone . Alcohol intoxication and burn injury independent of each other have also been shown to cause an increase in bacterial translocation . The gastrointestinal tract normally maintains a physical mucosal and immunologic barrier that provides an effective defense in keeping bacteria within the intestinal lumen . However, in injury conditions these defense mechanisms are impaired . Intestinal bacteria consequently gain access to extraintestinal sites . Intestine-derived bacteria are implicated in causing systemic infection and in subsequent multiple organ dysfunction in both immunocompromised patients and patients with injury, such as burn and trauma . In this article, we discuss three potential mechanisms that are likely to contribute to the increase in bacterial translocation in alcohol intoxication and burn injury: (1) increase in bacterial growth in the intestine, (2) physical disruption of mucosal barrier of the intestine, and (3) suppression of the immune defense in the intestine.

Bioinformatics, 2003 Sep 1, 19(13), 1707 - 9
Intergenic sequence inspector: searching and identifying bacterial RNAs; Pichon C et al.; Intergenic Sequence Inspector (ISI) is a program that helps in identifying bacterial ribonucleic acids (RNAs).It automatically extracts, selects and visualizes candidate intergenic regions (IGRs) that bear conservations between phylogenetically related species, displaying sequence and structural signatures of RNA genes encompassing putative promoters, terminators, RNA secondary structure predictions and the G+C percent of the selected sequences . ISI is intentionally modular to analyze various bacterial genomes according to their intrinsic specificities and to the available data . ISI provides a sum of information to the user who can evaluate whether or not an IGR is susceptible to express RNAs.

Eur Cell Mater, 2004 Dec 07, 8, 37 - 57; discussion 37-57
Concise review of mechanisms of bacterial adhesion to biomaterials and of techniques used in estimating bacteria-material interactions; Katsikogianni M et al.; This article reviews the mechanisms of bacterial adhesion to biomaterial surfaces, the factors affecting the adhesion, the techniques used in estimating bacteria-material interactions and the models that have been developed in order to predict adhesion . The process of bacterial adhesion includes an initial physicochemical interaction phase and a late molecular and cellular one . It is a complicated process influenced by many factors, including the bacterial properties, the material surface characteristics, the environmental factors, such as the presence of serum proteins and the associated flow conditions . Two categories of techniques used in estimating bacteria-material interactions are described: those that utilize fluid flowing against the adhered bacteria and counting the percentage of bacteria that detach, and those that manipulate single bacteria in various configurations which lend themselves to more specific force application and provide the basis for theoretical analysis of the receptor-ligand interactions . The theories that are reviewed are the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, the thermodynamic approach and the extended DLVO theory . Over the years, significant work has been done to investigate the process of bacterial adhesion to biomaterial surfaces, however a lot of questions still remain unanswered.

Am J Obstet Gynecol, 2004 Dec, 191(6), 1898 - 906
Intravaginal metronidazole gel versus metronidazole plus nystatin ovules for bacterial vaginosis: a randomized controlled trial; Sanchez S et al.; OBJECTIVE: We compared metronidazole 0.75% gel (containing 37.5 mg metronidazole per dose) with ovules containing metronidazole 500 mg and nystatin 100,000 U, for intravaginal treatment of bacterial vaginosis (BV) . STUDY DESIGN: In a single-blinded trial, symptomatic women with BV by both Amsel and Nugent criteria were randomly assigned to gel or ovules, once nightly for 5 nights, and asked to return 3 times after treatment . Analyses were intent-to-treat . RESULTS: Of 151 women with BV by both criteria at enrollment, 138 (91%) returned at least once . Product limit estimates for persistence or recurrence of BV at 14, 42, and 104 days were 20% (95% CI 10%-29%), 38% (95% CI 25%-48%), and 52% (95% CI 37%-63%) after gel treatment, and 4% (95% CI 0%-9%), 17% (95% CI 7%-26%), and 33% (95% CI 21%-46%) after ovule treatment ( P = .01) . Among women without BV at first follow-up, subsequent intercourse without condoms independently predicted subsequent recurrence ( P </= .01) . CONCLUSION: Metronidazole/nystatin ovules were significantly more effective than metronidazole gel . Unprotected sex predicted recurrence after initial improvement.

J Neuroimmunol, 2005 Jan, 158(1-2), 40 - 9
STAT3 activation and c-FOS expression in the brain following peripheral administration of bacterial DNA; Sako K et al.; To study the role of bacterial DNA in the brain function, we investigated signal transducer and activator of transcription 3 (STAT3) activation and c-FOS expression in the brain by immunohistochemistry in response to peripheral administration of CpG-DNA . CpG-DNA induced phospho-STAT3-immunoreactive cells and c-FOS-positive cells in several brain regions in a different manner . Phospho-STAT3-immunoreactive cells were observed in the circumventricular organs where the blood-brain barrier is weak . On the other hand, CpG-DNA increased c-FOS-positive cells in the paraventricular nucleus of the hypothalamus, and the nucleus of the tractus solitarius (NTS) and the area postrema . Unilateral cervical vagotomy did not modify CpG-DNA-induced c-FOS expression in the NTS, indicating that CpG-DNA-induced activation of the NTS is independent of the afferent vagus nerve input originating from the subdiaphragmatic organs . On the other hand, Toll-like receptor 9 mRNA was expressed in the nodose ganglion . Therefore, it is possible that CpG-DNA activates afferent vagus nerve through the nodose ganglion which subsequently activates the NTS . Present observations represented that peripheral CpG-DNA induced immune event in the brain, and that not only c-FOS but also phosphorylation of STAT3 can be a useful indicator for evaluation of neuro-immune interaction.

J Immunol, 2004 Dec 15, 173(12), 7490 - 6
IL-27 signaling compromises control of bacterial growth in mycobacteria-infected mice; Pearl JE et al.; Resistance to tuberculosis (TB) is dependent on the induction of Ag-specific CD4 Th1 T cells capable of expressing IFN-gamma . Generation of these T cells is dependent upon IL-12p70, yet other cytokines have also been implicated in this process . One such cytokine, IL-27, augments differentiation of naive T cells toward an IFN-gamma-producing phenotype by up-regulating the transcription factor T-bet and promoting expression of the IL-12Rbeta2 chain allowing T cells to respond to IL-12p70 . We show that the components of IL-27 are induced during TB and that the absence of IL-27 signaling results in an altered disease profile . In the absence of the IL-27R, there is reduced bacterial burden and an increased lymphocytic character to the TB granuloma . Although the number of Ag-specific CD4 IFN-gamma-producing cells is unaffected by the absence of the IL-27R, there is a significant decrease in the level of mRNA for IFN-gamma and T-bet within the lungs of infected IL-27R(-/-) mice . Ag-specific CD4 T cells in the lungs of IL-27R(-/-) also produce less IFN-gamma protein per cell . The data show that expression of IL-27 during TB is detrimental to the control of bacteria and that although it does not affect the number of cells capable of producing IFN-gamma it does reduce the ability of CD4 T cells to produce large amounts of IFN-gamma . Because IFN-gamma is detrimental to the survival of effector T cells, we hypothesize that the reduced IFN-gamma within the IL-27R(-/-) lung is responsible for the increased accumulation of lymphocytes within the mycobacterial granuloma.

J Immunol, 2004 Dec 15, 173(12), 7401 - 5
TLR2 recognizes a bacterial lipopeptide through direct binding; Vasselon T et al.; The TLRs play an important role in the initiation of cellular innate immune responses to a wide range of bacterial products, including LPS and lipoproteins . Although rapid progress has been made on signaling functions of activated TLRs, the molecular mechanisms that lead to TLR activation are still poorly understood . We report in this study that the extracellular domain of TLR2 interacts directly with synthetic bacterial lipopeptide (sBLP), a potent analog of bacterial lipoproteins . Using fluorescently labeled sBLP complexed to soluble recombinant CD14 (rsCD14), we observed specific binding of sBLP to the surface of cells expressing TLR2 transgenes and to a recombinant soluble form of the TLR2 ectodomain . TLR2-mediated binding of sBLP at the cell surface did not require prior induction of intracellular signals . In addition, using a chimeric TLR2/TLR4 construct, we showed that the leucine-rich region of TLR2 carries the specificity for binding of the agonist and for initiating signaling . Specific binding of fluorescent sBLP to purified sTLR2 required sCD14 . However, sCD14 was not part of the complex formed by soluble TLR2 and sBLP . Together, these data provide evidence that TLR2 recognizes sBLP through direct binding.

Rev Esp Enferm Dig, 2004 Nov, 96(11), 796 - 800
Amebic liver abscess with bacterial superinfection in a patient with no epidemiologic risk factors; Sachez Pobre P et al.; The amebic liver abscess is uncommon in developed countries like Spain, but the incidence is increasing probably due to the migratory movements of the population . We report a case of an amebic abscess, initially unsuspected due to the absence of epidemiologic risk factors and the negative serology for amebiasis, in the early stages of the disease.

Berl Munch Tierarztl Wochenschr, 2004 Nov-Dec, 117(11-12), 464 - 71
{Bacterial pathogen associated molecular pattern and superantigens indirectly induce the accelerated death of bovine neutrophilic granulocytes}; Schuberth HJ et al.; Pathogen associated molecular patterns (PAMPs) and bacterial superantigens have many effects on mononuclear cells (MNC) and macrophages . Influences on neutrophilic granulocytes (PMN), especially by non methylated CpG motifs, gained less attention . Here we investigated whether PAMPs and the superantigen SEA have a direct or indirect influence on the survival rate of bovine PMN . Different CpG motifs, a reverse GpC motif, Lipopolysaccharide (LPS) and SEA did not result in a loss of viability of pure PMN . In the presence of MNC or in vitro generated macrophages (MdM), however, they induced an accelerated dying of PMN . The simultaneous stimulation of MNC/MdM with combinations of CpG motifs and LPS or SEA resulted in an additive or over additive effect: compared to control set ups, only 28-36% of the PMN remained viable in SEA/CpG stimulated MNC/PMN cocultures . Comparing autologous with allogeneic MNC/PMN or MdM/PMN cocultures, it showed up that not only the stimulated MNC or MdM population but also the individual reaction state of the PMN have an influence on the degree of PMN dying . Taken together, CpG motifs and other PAMPs as well as superantigens act in concert to reduce indirectly the viability of neutrophilic granulocytes and hence the functional capacity of an important effector cell population.

Proc Natl Acad Sci U S A, 2004 Dec 21, 101(51), 17873 - 8 Epub 2004 Dec 06.
Reversed voltage-dependent gating of a bacterial sodium channel with proline substitutions in the S6 transmembrane segment; Zhao Y et al.; Members of the voltage-gated-like ion channel superfamily have a conserved pore structure . Transmembrane helices that line the pore (M2 or S6) are thought to gate it at the cytoplasmic end by bending at a hinge glycine residue . Proline residues favor bending of alpha-helices, and substitution of proline for this glycine (G219) dramatically stabilizes the open state of a bacterial Na(+) channel NaChBac . Here we have probed S6 pore-lining residues of NaChBac by proline mutagenesis . Five of 15 proline-substitution mutants yielded depolarization-activated Na(+) channels, but only G219P channels have strongly negatively shifted voltage dependence of activation, demonstrating specificity for bending at G219 for depolarization-activated gating . Remarkably, three proline-substitution mutations on the same face of S6 as G219 yielded channels that activated upon hyperpolarization and inactivated very slowly . Studies of L226P showed that hyperpolarization to -147 mV gives half-maximal activation, 123 mV more negative than WT . Analysis of combination mutations and studies of block by the local anesthetic etidocaine favored the conclusion that hyperpolarization-activated gating results from opening of the cytoplasmic gate formed by S6 helices . Substitution of multiple amino acids for L226 indicated that hyperpolarization-activated gating was correlated with a high propensity for bending, whereas depolarization-activated gating was favored by a low propensity for bending . Our results further define the dominant role of bending of S6 in determining not only the voltage dependence but also the polarity of voltage-dependent gating . Native hyperpolarization-activated gating of hyperpolarization- and cyclic nucleotide-gated (HCN) channels in animals and KAT channels in plants may involve bending at analogous S6 amino acid residues.

Biochem Biophys Res Commun, 2005 Jan 14, 326(2), 290 - 7
Mutational study of the bacterial hemoglobin distal heme pocket; Verma S et al.; Ligand binding experiments on three mutants in the distal heme pocket of Vitreoscilla hemoglobin (GlnE7His, ProE8Ala, and GlnE7His,ProE8Ala) were used to probe the role of GlnE7 and ProE8 in the pocket's unusual structure . The oxygen dissociation constants for the wild type, E8Ala mutant, and E7His mutant proteins were 4.5, 4.7, and 1.7microM, respectively; the K(d) for the double mutant was not determinable by our technique . Visible-Soret spectra of the carbonyl and cyanyl forms and FT-IR of the carbonyl form of the E8 mutant were similar to those of the wild type; the opposite was true for the GlnE7His and GlnE7His,ProE8Ala mutants, which also differed from wild type in the visible-Soret spectra of their oxidized forms . Models of the effects of the mutations on distal pocket structure were consistent with the experimental findings, particularly the larger effects of the GlnE7His change.

Curr Opin Struct Biol, 2004 Dec, 14(6), 731 - 40
Structural insights into bacterial modulation of the host cytoskeleton; Stebbins CE; Many bacterial pathogens manipulate the host cell cytoskeleton during infection . Such cytoskeletal modulation can occur at several points of contact between the pathogen and the host, and involves extracellular receptors, intracellular signal transduction and cytoskeletal proteins themselves . The field of bacterial pathogenesis has progressed dramatically over the past decade, such that structural knowledge is both timely and essential for a full appreciation of the biology at the pathogen-host interface . Several recent examples involving bacterial proteins that target actin, Rho family GTPases and extracellular receptors have contributed to a structural understanding of eukaryotic cytoskeletal modulation by pathogens.

Arch Biochem Biophys, 2005 Jan 1, 433(1), 240 - 54
Bacterial defenses against oxidants: mechanistic features of cysteine-based peroxidases and their flavoprotein reductases; Poole LB; Antioxidant defenses include a group of ubiquitous, non-heme peroxidases, designated the peroxiredoxins, which rely on an activated cysteine residue at their active site to catalyze the reduction of hydrogen peroxide, organic hydroperoxides, and peroxynitrite . In the typical 2-Cys peroxiredoxins, a second cysteinyl residue, termed the resolving cysteine, is also involved in intersubunit disulfide bond formation during the course of catalysis by these enzymes . Many bacteria also express a flavoprotein, AhpF, which acts as a dedicated disulfide reductase to recycle the bacterial peroxiredoxin, AhpC, during catalysis . Mechanistic and structural studies of these bacterial proteins have shed light on the linkage between redox state, oligomeric state, and peroxidase activity for the peroxiredoxins, and on the conformational changes accompanying catalysis by both proteins . In addition, these studies have highlighted the dual roles that the oxidized cysteinyl species, cysteine sulfenic acid, can play in eukaryotic peroxiredoxins, acting as a catalytic intermediate in the peroxidase activity, and as a redox sensor in regulating hydrogen peroxide-mediated cell signaling.

Biochemistry, 2004 Dec 14, 43(49), 15633 - 42
Alpha-glucan recognition by a new family of carbohydrate-binding modules found primarily in bacterial pathogens; Lammerts van Bueren A et al.; TmPul13, a family 13 glycoside hydrolase from Thermotoga maritima, is a four-module protein having pullulanase activity; the three N-terminal modules are of unknown function while the large C-terminal module is likely the catalytic module . Dissection of the functions of the three unknown modules revealed that the 100 amino acid module at the extreme N-terminus of TmPul13 comprises a new family of carbohydrate-binding modules (CBM) that a bioinformatic analysis shows are most frequently found in pullulanase-like sequences from bacterial pathogens . Detailed binding studies of this isolated CBM, here called TmCBM41, reveals a preference for alpha-(1,4)-linked glucans, but occasional alpha-(1,6)-linked glucose residues, such as those found in pullulan, are tolerated . UV difference, isothermal titration calorimetry, and analytical ultracentrifugation binding studies suggest that maltooligosaccharides longer than four glucose residues are able to bind two TmCBM41 molecules per oligosaccharide when sugar concentrations are below the CBM concentration . This is explained in terms of an equilibrium expression involving the formation of both a 1 to 1 sugar to CBM complex and a 1 to 2 sugar to CBM complex (i.e., a CBM dimer ligated by an oligosaccharide) . The presence of an alpha-(1-6) linkage in the oligosaccharide appears to prevent this phenomenon.

Med Oral Patol Oral Cir Bucal, 2004, 9 Suppl, 34 - 6; 32-4
Bacterial infections of pulp and periodontal origin; Gonzalez-Moles MA et al.; The anatomical and structural characteristics of the pulp make this structure prone to altering as a result of, for instance, periodontal conditions (proximity), iatrogenic alterations, infections and involvement of vascular and nerve structures (it is surrounded by hard tissues that prevent expansion), to name just a few . Pulpitis is a process that courses with pain of varying intensity that allows us to determine the location of the lesion in clinical terms . Its evolution varies and may even progress to pulpar necrosis that in turn, produces neuritis-like pain . Diagnosis is established by means of clinical symptomatology and supported by X-rays, palpation of tissues at painful sites, application of electrical stimuli, heat, etc . Periodontitis is a bacterial infection originating in the apex . The most important form is the so-called acute apical periodontitis that arises as a result of a prior episode of pulpitis . It is characterized by acute pain located in the tooth, accompanied by the feeling of having a long-tooth . The patient refers being unable to chew on that side; there may be painful mobility of the tooth and an outflow of pus that alleviates symptoms . X-rays do not provide a lot of information, but may attest to a widening of the apical space . This pathology may disseminate to surrounding tissues, leading to conditions of considerable severity.

Curr Drug Targets Infect Disord, 2004 Dec, 4(4), 303 - 9
Advances in adjuvant therapy against acute bacterial meningitis; Pomar V et al.; Death and co-morbidity derived from acute bacterial meningitis remain unacceptably high and are mainly related to immune-mediated cerebral dysfunction . Cerebral edema, hydrocephalus and ischaemic cerebrovascular events are severe complications that eventually occur following the activation of a complex network of cytokines, chemokines, proteases and oxidants released after cerebrospinal fluid infection . The caspase pathway appears to play a central role in the induction and amplification of the host inflammatory response . Such overactive immune reactions induce brain cell damage but, importantly, they may potentially be blocked . Several agents have been developed aiming to counteract the deleterious effects of such immune imbalance . These drugs are candidates to become adjuvant therapy against acute bacterial meningitis in the future, in addition to dexamethasone . We review the current state-of-art of bacterial meningitis adjuvant therapy, including caspase inhibitors, antioxidants, poly (ADP-ribose) polymerase inhibitors, inhibitors of lipid peroxidation and metalloproteinase inhibitors.

Nature, 2004 Dec 2, 432(7017), 622 - 5
A candidate NAD+ transporter in an intracellular bacterial symbiont related to Chlamydiae; Haferkamp I et al.; Bacteria living within eukaryotic cells can be essential for the survival or reproduction of the host but in other cases are among the most successful pathogens . Environmental Chlamydiae, including strain UWE25, thrive as obligate intracellular symbionts within protozoa; are recently discovered relatives of major bacterial pathogens of humans; and also infect human cells . Genome analysis of UWE25 predicted that this symbiont is unable to synthesize the universal electron carrier nicotinamide adenine dinucleotide (NAD+) . Compensation of limited biosynthetic capacity in intracellular bacteria is usually achieved by import of primary metabolites . Here, we report the identification of a candidate transporter protein from UWE25 that is highly specific for import of NAD+ when synthesized heterologously in Escherichia coli . The discovery of this candidate NAD+/ADP exchanger demonstrates that intact NAD+ molecules can be transported through cytoplasmic membranes . This protein acts together with a newly discovered nucleotide transporter and an ATP/ADP translocase, and allows UWE25 to exploit its host cell by means of a sophisticated metabolic parasitism.

Otolaryngol Head Neck Surg, 2004 Dec, 131(6), 871 - 6
Bacterial tracheitis reexamined: is there a less severe manifestation?
Salamone FN, Bobbitt DB, Myer CM, Rutter MJ, Greinwald JH Jr.
OBJECTIVE: Bacterial tracheitis (BT) is a condition that can cause fatal airway obstruction . We evaluated our experience with BT over a 10-year period . STUDY DESIGN: Retrospective review of patients treated for BT between 1991 and 2001 . RESULTS: Ninety-four cases were evaluated . The mean patient age was 7.9 years . At presentation, 60% were afebrile, and the mean WBC count was 10.8 x 10(3)/mm3 . Only 53% of patients required intubation . Younger children were more likely to require this intervention . S . aureus was the most commonly cultured bacteria, while isolation of M . catarrhalis was associated with a higher intubation rate . A pathologic virus was isolated in 64% of the 34 cultures performed . Only 9 patients were described as "toxic," and 6 presented in respiratory extremis . There were no deaths . CONCLUSION AND SIGNIFICANCE: A subset of patients with tracheal membranes has a less severe clinical appearance . Nonetheless, these patients require debridement and aggressive medical treatment . We propose that the term "exudative tracheitis" (ET) better describes this entity . Older patients who are less systemically ill and rapidly respond to local and systemic therapy are characteristic of ET . EBM RATING: C.

Nucleic Acids Res, 2004, 32(21), 6260 - 7 Print 2004.
Repair of 3-methylthymine and 1-methylguanine lesions by bacterial and human AlkB proteins; Falnes PO; The Escherichia coli AlkB protein repairs 1-methyladenine (1-meA) and 3-methylcytosine (3-meC) lesions in DNA and RNA by oxidative demethylation, a reaction requiring ferrous iron and 2-oxoglutarate as cofactor and co-substrate, respectively . Here, we have studied the activity of AlkB proteins on 3-methylthymine (3-meT) and 1-methylguanine (1-meG), two minor lesions which are structurally analogous to 1-meA and 3-meC . AlkB as well as the human AlkB homologues, hABH2 and hABH3, were all able to demethylate 3-meT in a DNA oligonucleotide containing a single 3-meT residue . Also, 1-meG lesions introduced by chemical methylation of tRNA were efficiently removed by AlkB . Unlike 1-meA and 3-meC, nucleosides or bases corresponding to 1-meG or 3-meT did not stimulate the uncoupled, AlkB-mediated decarboxylation of 2-oxoglutarate . Our data show that 3-meT and 1-meG are repaired by AlkB, but indicate that the recognition of these substrates is different from that in the case of 1-meA and 3-meC.

Environ Sci Technol, 2004 Nov 1, 38(21), 5656 - 64
Cd and proton adsorption onto bacterial consortia grown from industrial wastes and contaminated geologic settings; Borrok DM et al.; To model the effects of bacterial metal adsorption in contaminated environments, results from metal adsorption experiments involving individual pure stains of bacteria must be extrapolated to systems in which potentially dozens of bacterial species are present . This extrapolation may be made easier because bacterial consortia from natural environments appear to exhibit similar metal binding properties . However, bacteria that thrive in highly perturbed contaminated environments may exhibit significantly different adsorptive behavior . Here we measure proton and Cd adsorption onto a range of bacterial consortia grown from heavily contaminated industrial wastes, groundwater, and soils . We model the results using a discrete site surface complexation approach to determine binding constants and site densities for each consortium . The results demonstrate that bacterial consortia from different contaminated environments exhibit a range of total site densities (approximately a 3-fold difference) and Cd-binding constants (approximately a 10-fold difference) . These ranges for Cd binding constants may be small enough to suggest that bacteria-metal adsorption in contaminated environments can be described using relatively few "averaged" bacteria-metal binding constants (in conjunction with the necessary binding constants for competing surfaces and ligands) . However, if additional precision is necessary, modeling parameters must be developed separately for each contaminated environment of interest.

Appl Environ Microbiol, 2004 Dec, 70(12), 7070 - 7
Bacterial life and dinitrogen fixation at a gypsum rock; Boison G et al.; The organisms of a bluish-green layer beneath the shards of a gypsum rock were characterized by molecular techniques . The cyanobacterial consortium consisted almost exclusively of Chroococcidiopsis spp . The organisms of the shards expressed nitrogenase activity (C2H2 reduction) aerobically and in light . After a prolonged period of drought at the rock, the cells were inactive, but they resumed nitrogenase activity 2 to 3 days after the addition of water . In a suspension culture of Chroococcidiopsis sp . strain PCC7203, C2H2 reduction required microaerobic conditions and was strictly dependent on low light intensities . Sequencing of a segment of the nitrogenase reductase gene (nifH) indicated that Chroococcidiopsis possesses the alternative molybdenum nitrogenase 2, expressed in Anabaena variabilis only under reduced O2 tensions, rather than the widespread, common molybdenum nitrogenase . The shards apparently provide microsites with reduced light intensities and reduced O2 tension that allow N2 fixation to proceed in the unicellular Chroococcidiopsis at the gypsum rock, unless the activity is due to minute amounts of other, very active cyanobacteria . Phylogenetic analysis of nifH sequences tends to suggest that molybdenum nitrogenase 2 is characteristic of those unicellular or filamentous, nonheterocystous cyanobacteria fixing N2 under microaerobic conditions only.

Surgeon, 2003 Apr, 1(2), 63 - 75
Inflammatory bowel disease: dysfunction of GALT and gut bacterial flora (I); Chandran P et al.; Gut-associated lymphoid tissue (GALT) is the largest lymphoid organ in the body . This is not surprising considering the huge load of antigens (Ags) from food and commensal bacteria with which it interacts on a daily basis . Gut-associated lymphoid tissue has to recognise and allow the transfer of beneficial Ags whilst concurrently dealing with and successfully removing putative and overtly harmful Ags . This distinctive biological feature of GALT is believed to be crucial to good health . Deregulation or dysfunction of GALT is thought to predispose to inflammatory bowel diseases (IBD) such as ulcerative colitis and Crohn's disease . The exact mechanism(s) underlying the pathogenesis of IBD is (are) poorly understood and the immunological defects in GALT are poorly documented . Advances in immunology have highlighted the importance of dendritic cells (DCs), which are the key Ag presenting cells in tissues and lymphoid compartments . Their crucial role in GALT, in health and disease is discussed in this review . Interaction of DCs with T cells in the gut produces a subset of T lymphocytes, which have immunosuppressive function . Inappropriate Ag uptake and presentation to naive T cells in mesenteric lymph nodes may lead to T cell tolerance in GALT . These various complex factors in the gut are discussed and their possible relevance to IBD evaluated.

Environ Sci Technol, 2004 Nov 15, 38(22), 5925 - 31
Uncertainty analysis in a mechanistic model of bacterial regrowth in distribution systems; Digiano FA et al.; The first generation of mechanistic models of bacterial regrowth in distribution systems (DS) provides insight into cause-and-effect relationships . However, the state of knowledge about the processes included in these models is insufficient to warrant deterministic predictions . Even if the process descriptions are reasonable, the uncertainty in values of key system constants limits predictions of bacterial growth . A new mechanistic model was developed to incorporate the accepted knowledge of physical, chemical, and biological processes with the hydraulic features in order to capture the unsteady state behavior of the DS . Sensitivitytesting showed that the extent of bacterial regrowth was affected mainly by the rate constants for chlorine decay reactions in bulk water and on the pipe wall and by the maximum growth rate constant of attached bacteria . A simple hypothetical network was used to evaluate the effects of uncertainty in these three system constants by running 100 Monte Carlo simulations . Cumulative probability plots showed a wide range of predictions for concentrations of bacteria and chlorine in bulk water at various nodes in the DS . The magnitude of these concentrations and the range of values were greatly affected by water residence time to each node . Once the chlorine residual is depleted, bacterial growth is mainly influenced by the amount of substrate available . However, high values of the coefficients for the maximum growth rate of attached bacteria, the chlorine decay in bulk water, and the chlorine decay by wall reaction did not necessarily lead to the maximum bacterial growth at a given location.

Nat Rev Mol Cell Biol, 2004 Dec, 5(12), 1024 - 37
Making sense of it all: bacterial chemotaxis; Wadhams GH et al.; Bacteria must be able to respond to a changing environment, and one way to respond is to move . The transduction of sensory signals alters the concentration of small phosphorylated response regulators that bind to the rotary flagellar motor and cause switching . This simple pathway has provided a paradigm for sensory systems in general . However, the increasing number of sequenced bacterial genomes shows that although the central sensory mechanism seems to be common to all bacteria, there is added complexity in a wide range of species.

Acta Microbiol Immunol Hung, 2004, 51(3), 249 - 61
Studies on bacterial conjugational crosses via model populations . II . Genetic studies; Alfoldi L; Model populations, simulating progenies obtained from Escherichia coli Hfr x F- crosses, are generated . Linkage relations and exchange frequencies are expressed in these populations in complex, in some cases, even paradoxical manner . It is demonstrated that the origin of the complexities is located in the particular allelic configuration of the genotypes, characteristic for all exconjugant and selected populations.

Acta Microbiol Immunol Hung, 2004, 51(3), 239 - 47
Studies on bacterial conjugational crosses via model populations . I . The model populations; Alfoldi L; A procedure is presented in which model populations, simulating progenies obtained from Escherichia coli Hfr x F- crosses, are generated . The procedure seems to be appropriate for visualizing hidden features of the genetic analysis, which are not detected by the conjugational crosses.

Surgeon, 2003 Jun, 1(3), 125 - 36
Inflammatory bowel disease: dysfunction of GALT and gut bacterial flora (II); Chandran P et al.; The precise cause(s) of Crohn's disease and ulcerative colitis are unknown . From animal models and human studies it is well established that gut bacterial flora are essential for inducing the bowel inflammation . Animal models, when kept in a germ-free environment, do not develop colitis until the gut flora is reconstituted . It is not clear whether the bacterial antigens (Ags) from the normal flora or some other pathogenic bacterial Ags induce/propagate the inflammatory process in inflammatory bowel disease (IBD) . Despite extensive research it has not been possible to identify any specific bacteria or virus as a credible cause of IBD . Recent understanding of quorum sensing molecules (QSMs) secreted by bacteria helps to explain the community behaviour in bacterial species . When QSMs reach a defined concentration, they activate bacterial proliferation and a number of virulence genes . Also, these molecules have been found to modulate the immune system to the advantage of the gut bacteria . They have not been well studied, however, in the gut . Inappropriate secretion of QSMs may alter the gut-associated lymphoid tissue (GALT) and, thereby, deregulate the immune tolerance normally present . Usefulness of probiotics and their immune modulating effects are being increasingly reported . Probiotics are also being used in the treatment of IBD . The interaction between the epithelial cells and the gut flora is very important as this is the first line of contact; this interaction may determine the induction of tolerance and mucosal integrity or immune activity, tissue inflammation and abnormal permeability . The latter is documented in patients with IBD and their healthy relatives . This may be an important factor in disruption of mucosal integrity and GALT dysfunction.

J Reprod Med, 2004 Oct, 49(10), 781 - 6
Clinical variability of bacterial vaginosis and trichomoniasis; Brown D Jr; Bacterial vaginosis and trichomoniasis are two of the most commonly encountered vaginal diseases . Although risk factors for both vaginal conditions have been identified, there continues to be lack of knowledge in regard to their role in association with other sexually transmitted diseases . Vaginal pH is an essential ingredient in the defense and control of the vaginal environment . The alteration of pH with the sequelae of such pregnancy complications as preterm delivery, preterm labor and premature rupture of the membranes; amniotic fluid infection; postpartum endometritis and surgical infections; and the role of bacterial vaginosis are discussed . Treatment modalities in both the nonpregnant and pregnant woman, as well as treatment of resistant cases of both vaginal conditions, are recommended.

J Microbiol Methods, 2005 Jan, 60(1), 55 - 62
A rapid microplate method for quantifying inhibition of bacterial adhesion to eukaryotic cells; Acord J et al.; Adhesion of bacteria to the mucosal epithelial cell surface is the first step in infection, and studies have shown that inhibition of this step may be useful therapeutically . To test compounds that may prevent bacterial binding to a number of epithelial cell lines, we have developed a high-throughput adhesion assay using a microtitre plate system and bacteria that have been modified to express firefly luciferase . This method has proved to be a sensitive, rapid, and reproducible system for screening antiadhesive agents for their effects on bacterial adhesion.

J Microbiol Methods, 2005 Jan, 60(1), 41 - 6
Activity-dependent fluorescent labeling of bacterial cells expressing the TOL pathway; Clingenpeel SR et al.; 3-Ethynylbenzoate (3EB) functions as a novel, activity-dependent, fluorogenic, and chromogenic probe for bacterial strains expressing the TOL pathway, which degrade toluene via conversion to benzoate, followed by meta ring fission of the intermediate catechol . This direct physiological analysis allows the fluorescent labeling of cells whose toluene-degrading enzymes have been induced by an aromatic substrate.

Nihon Kokyuki Gakkai Zasshi, 2004 Oct, 42(10), 871 - 4
{Study of administration times and clinical efficacy of carbapenems in the treatment of moderate community-acquired bacterial pneumonia}; Okimoto N et al.; The half-lives of carbapenems are about 1 hour . It was expected that increasing the daily frequency of administration would improve the clinical effects . We therefore studied the clinical effects of increasing the daily administration frequency of meropenem in the treatment of community-acquired bacterial pneumonia . The subjects were patients with moderate community-acquired bacterial pneumonia who were aged less than 75 years . They were divided into a BID group (28 patients receiving 0.5 g morning and evening) and a TID group (27 patients receiving 0.25 g in the morning and about midday, and 0.5 g in the evening), and the clinical effects were reviewed prospectively . Clinical efficacy on the third day was 78.6% in the BID group and 85.2% in the TID group, and over-all clinical efficacy was 89.3% in the BID group and 88.9% in the TID group . Administration periods were 12.8 +/- 4.2 days in the BID group and 10.9 +/- 3.4 days in the TID group . These results show no statistically significant difference, and suggest that the excellent clinical effect of administration of MEPM 0.5 g twice a day on moderate community-acquired bacterial pneumonia is not improved by administration three times a day.

Can J Gastroenterol, 2004 Nov, 18(11), 677 - 80
Deadaption and readaptation with lactose, but no cross-adaptation to lactulose: a case of occult colonic bacterial adaptation; Szilagyi A et al.; The standard 3 h breath hydrogen (3hBH2) test distinguishes lactose maldigesters from lactose digesters . However, multiple factors impact on BH2 and care is needed to exclude a priori variables . When these factors are controlled, a negative BH2 test implies lactase persistent status or lactase nonpersistent status with colonic adaptation . A case of a Sicilian man who tested negative (lactase persistent status confirmed) on an initial 50 g lactose challenge is described . It was observed that he consumed 28.1 g lactose/day before testing . He subsequently underwent five additional challenge tests in the course of the next 10 months . In four tests the dose intake of lactose was varied upon instruction, and in the fifth test a 30 g lactulose challenge was carried out . It was demonstrated that on radically decreasing lactose intake, a full lactase nonpersistent status was unmasked . Output of 3hBH2 varied inversely with daily lactose intake . Finally, at a time when he was readapted to lactose, there was no discernible adaptation to lactulose challenge . It was concluded that 'occult' colonically adapted subjects may contribute to negative BH2 tests . There is a relationship between variation in lactose intake and the results of BH2 testing . Finally, there was no cross-adaptation to lactulose challenge when lactose was used as the adapting sugar.

Thorax, 2004 Dec, 59(12), 1057 - 62
Protective role of metallothionein in acute lung injury induced by bacterial endotoxin; Takano H et al.; BACKGROUND: Metallothionein (MT) is a protein that can be induced by inflammatory mediators and participate in cytoprotection . However, its role in inflammation remains to be established . A study was undertaken to determine whether intrinsic MT protects against acute inflammatory lung injury induced by bacterial endotoxin in MT-I/II knock out (-/-) and wild type (WT) mice . METHODS: MT (-/-) and WT mice were given vehicle or lipopolysaccharide (LPS, 125 microg/kg) intratracheally and the cellular profile of the bronchoalveolar lavage (BAL) fluid, pulmonary oedema, lung histology, expression of proinflammatory molecules, and nuclear localisation of nuclear factor-kappaB (NF-kappaB) in the lung were evaluated . RESULTS: MT (-/-) mice were more susceptible than WT mice to lung inflammation, especially to lung oedema induced by intratracheal challenge with LPS . After LPS challenge, MT deficiency enhanced vacuolar degeneration of pulmonary endothelial cells and type I alveolar epithelial cells and caused focal loss of the basement membrane . LPS treatment caused no significant differences in the enhanced expression of proinflammatory cytokines and chemokines nor in the activation of the NF-kappaB pathway in the lung between the two genotypes . Lipid peroxide levels in the lungs were significantly higher in LPS treated MT (-/-) mice than in LPS treated WT mice . CONCLUSIONS: Endogenous MT protects against acute lung injury related to LPS . The effects are possibly mediated by the enhancement of pulmonary endothelial and epithelial integrity, not by the inhibition of the NF-kappaB pathway.

J Am Soc Echocardiogr, 2004 Dec, 17(12), 1315 - 6
Coronary artery fistula presenting as bacterial endocarditis; Kasravi B et al.; Coronary artery fistula is often considered to be a benign and rare congenital anomaly . It is usually an incidental finding encountered during routine cardiac catheterization . We report a case of a patient presenting with endocarditis involving a large coronary artery fistula connecting an aneurysmal circumflex coronary artery to the coronary sinus . The diagnosis was initially made by echocardiography and confirmed by cardiac catheterization . In addition, we briefly discuss the literature on management of this coronary anomaly.

Curr Opin Biotechnol, 2004 Dec, 15(6), 530 - 7
Bacterial ghosts--biological particles as delivery systems for antigens, nucleic acids and drugs; Tabrizi CA et al.; Despite the exponential rate of discovery of new antigens and DNA vaccines resulting from modern molecular biology and proteomics, the lack of effective delivery technology is a major limiting factor in their application . The bacterial ghost system represents a platform technology for antigen, nucleic acid and drug delivery . Bacterial ghosts have significant advantages over other engineered biological delivery particles, owing to their intrinsic cellular and tissue tropic abilities, ease of production and the fact that they can be stored and processed without the need for refrigeration . These particles have found both veterinary and medical applications for the vaccination and treatment of tumors and various infectious diseases.

Mol Biol Rep, 2004 Sep, 31(3), 159 - 64
Mammalian apoptosis-inducing protein, HAP, induces bacterial cell death; Gan M et al.; In attempting to produce the HAP, endoplasmic reticulum (ER) targeted apoptosis-inducing protein, as a GST-fusion protein we found that the expression of HAP, but not GST alone, induced bacterial cell death . The HAP protein inhibited the bacterial growth within 30 min after inducting HAP expression . The transmission electron microscopic examination revealed that the morphology of the bacterial cells expressing hap was changed dramatically: unusually elongated phenotype compared with those of controls and finally leading to cell death . The lethality of HAP was relieved by the addition of vitamin E as a reducing agent and under anaerobic growth conditions . These results suggest that a trace amount of HAP induces bacterial cell death and the death is related with reactive oxygen species (ROS).

Urologiia, 2004 Sep-Oct, (5), 31 - 4
{Naiz (nimesulid) in combined treatment of patients with chronic bacterial prostatitis with chronic pelvic pain syndrome}; Long-term survival of dialysis patients with bacterial endocarditis in the United States; Department of Internal Medicine, Hennepin County Medical Center and University of Minnesota, Minneapolis, MN, USABACKGROUND: The incidence of bacterial endocarditis is much greater in long-term dialysis patients compared with the general population, and chronic kidney disease has been postulated as an independent host-related risk factor . Limited data are available on the long-term survival of dialysis patients with endocarditis . METHODS: Dialysis patients hospitalized for bacterial endocarditis between 1977 and 2000 were studied retrospectively using data from the US Renal Data System database . Long-term survival was estimated by means of the life-table method . A Cox proportional hazards model was used to identify the impact of demographic characteristics and comorbidity on outcome . RESULTS: A total of 13,130 dialysis patients with bacterial endocarditis were identified . The in-hospital mortality rate for the entire cohort was 23.5% . Survival rates at 1, 2, 3, and 5 years were 45.9%, 33.3%, 24.3%, and 14.7% for patients hospitalized between 1977 and 1991 and 41.0%, 29.1%, 20.6%, and 10.9% for those hospitalized between 1992 and 1996, respectively . Survival rates at 1, 2, and 3 years were 38.4%, 25.3%, and 18.3% for patients hospitalized between 1997 and 2000, respectively . The most powerful independent predictors of all-cause death were age, diabetes as cause of end-stage renal disease, and cerebrovascular accident or transient ischemic attack as a comorbid condition . CONCLUSION: Dialysis patients with bacterial endocarditis have poor long-term survival, even in the current treatment era, with survival rates changing little in the past 2 decades . Additional studies are needed to identify risk-reduction measures and develop additional treatment strategies for dialysis patients with endocarditis.

J Exp Biol, 2004 Dec 1, 207(Pt 25), 4479 - 88
Bacterial lipopolysaccharide (LPS) modulates corticotropin-releasing hormone (CRH) content and release in the brain of juvenile and adult tilapia (Oreochromis mossambicus; Teleostei); Pepels PP et al.; Although immune endocrine interactions in teleost fish have been shown to involve adrenocorticotropin hormone (ACTH) and cortisol, the involvement of corticotropin-releasing hormone (CRH) has not been demonstrated . The present study investigates whether treatment with bacterial endotoxin (lipopolysaccharide, LPS) modulates brain CRH contents or in vitro CRH release in tilapia (Oreochromis mossambicus) . 10 days LPS (Escherichia coli) exposure of juvenile tilapia (4.5 weeks post hatch) via the ambient water increased brain CRH and alpha-MSH content, whereas cortisol contents were not increased . This indicates that the elevation of brain CRH levels were not secondary to activation of HPI-axis . Adult tilapia were treated for 6 days with LPS (intraperitoneally) and were sampled before and after 24 h of confinement . Overall LPS pre-treatment modified the reaction of tilapia to the additional stressor of 24 h confinement, as interactions between LPS treatment and confinement were observed at the level of the hypothalamus (diencephalic CRH content), the pituitary (CRH and alpha-MSH content) and in plasma glucose levels . In vitro, LPS pre-treatment abolished CRH release from telencephalic tissues induced by norepinephrine, one of the CRH secretagogues released during stress in vivo . This effect might be a mechanism of action through which LPS in vivo abolished the up-regulation of telencephalic CRH induced by confinement stress . Our results provide evidence that the role of CRH in immune-endocrine interactions is a phylogenetically old mechanism, and we here demonstrate that LPS molecules are able to locally modulate CRH release in the central nervous system.

Biophys J . 2004 Nov 19; {Epub ahead of print}
Phosphatidylethanolamine-phosphatidylglycerol bilayer as a model of the inner bacterial membrane; Murzyn K et al.; Phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) are the main lipid components of the inner bacterial membrane . A computer model for such a membrane was built of palmitoyloleoylPE (POPE) and palmitoyloleoylPG (POPG) in the proportion 3:1, and sodium ions (Na+) to neutralize the net negative charge on each POPG (POPE-POPG bilayer) . The bilayer was simulated for 25 ns . A final 10-ns trajectory fragment was used for analyses . In the bilayer interfacial region, POPEs and POPGs interact readily with one another via intermolecular hydrogen (H) bonds and water bridges . POPE is the main H bond donor in either PEPE or PEPG H bonds; PGPG H bonds are rarely formed . Almost all POPEs are H bonded and/or water bridged to either POPE or POPG but PE-PG links are favored . In effect, the atom packing in the near-the-interface regions of the bilayer core is tight . Na+ does not bind readily to lipids and inter-lipid links via Na+ are not numerous . Although POPG and POPE comprise one bilayer, their bilayer properties differ . The average surface area per POPG is larger and the average vertical location of the POPG phosphate group is lower than those of POPE . Also, the alkyl chains of POPG are more ordered and less densely packed than the POPE chains . The main conclusion of this study is that in the PE-PG bilayer PE interacts more strongly with PG than PE . This is a likely molecular level event behind a regulating mechanism developed by the bacteria to control its membrane permeability and stability consisting in changes of the relative PG to PE concentration in the membrane.

Curr Opin Microbiol, 2004 Dec, 7(6), 572 - 8
Spatial complexity of mechanisms controlling a bacterial cell cycle; Viollier PH et al.; Cell cycle progression in Caulobacter is governed by a multilayered regulatory network linking chromosome replication with polar morphogenesis and cell division . Temporal and spatial regulation have emerged as the central themes, with the abundance, activity and subcellular location of key structural and regulatory proteins changing over the course of the cell cycle . An additional layer of complexity was recently uncovered, showing that each segment of the chromosome is located at a specific cellular position both during and after the completion of DNA replication, raising the possibility that this positioning contributes to temporal and spatial control of gene expression.

Chem Biol, 2004 Nov, 11(11), 1553 - 9
Bacterial biosynthesis of cadmium sulfide nanocrystals; Sweeney RY et al.; Semiconductor nanocrystals, which have unique optical and electronic properties, have potential for applications in the emerging field of nanoelectronics . To produce nanocrystals cheaply and efficiently, biological methods of synthesis are being explored . We found that E . coli, when incubated with cadmium chloride and sodium sulfide, have the capacity to synthesize intracellular cadmium sulfide (CdS) nanocrystals . The nanocrystals are composed of a wurtzite crystal phase with a size distribution of 2-5 nm . Nanocrystal biosynthesis increased about 20-fold in E . coli cells grown to stationary phase compared to late logarithmic phase . Our results highlight how different genetic and physiological parameters can enhance the formation of nanocrystals within bacterial cells.

Chem Biol, 2004 Nov, 11(11), 1543 - 52
bryA: an unusual modular polyketide synthase gene from the uncultivated bacterial symbiont of the marine bryozoan Bugula neritina; Hildebrand M et al.; "Candidatus Endobugula sertula," the uncultivated bacterial symbiont of Bugula neritina, is the proposed source of the bryostatin family of anticancer compounds . We cloned a large modular polyketide synthase (PKS) gene complex from "Candidatus Endobugula sertula" and characterized one gene, bryA, which we propose is responsible for the initial steps of bryostatin biosynthesis . Typical PKS domains are present . However, acyltransferase domains are lacking in bryA, and beta-ketoacyl synthase domains of bryA cluster with those of PKSs with discrete, rather than integral, acyltransferases . We propose a model for biosynthesis of the bryostatin D-lactate starter unit by the bryA loading module, utilizing atypical domains homologous to FkbH, KR, and DH . The bryA gene product is proposed to synthesize a portion of the pharmacologically active part of bryostatin and may be useful in semisynthesis of clinically useful bryostatin analogs.

Colloids Surf B Biointerfaces, 2004 Dec 25, 39(4), 199 - 205
Surface free energy and bacterial retention to saliva-coated dental implant materials-an in vitro study; Mabboux F et al.; The aim of the present investigation was to compare the in vitro bacterial retention on saliva-coated implant materials (pure titanium grade 2 (cp-Ti) and a titanium alloy (Ti-6Al-4V) surfaces), presenting similar surface roughness, and to assess the influence of physico-chemical surface properties of bacterial strain and implant materials on in vitro bacterial adherence . Two bacterial strains (one hydrophilic strain and one hydrophobic strain) were used and the following were evaluated: bacterial cell adherence, SFE values as well as the Lifshitz-van-der Waals, the Lewis acid base components of SFE, the interfacial free energy and the non-dispersive interactions according to two complementary contact angle measurement methods: the sessile drop method and the captive bubble method . Our results showed similar patterns of adherent bacterial cells on saliva-coated cp-Ti and saliva-coated Ti-6Al-4V . These findings could suggest that bacterial colonization (i.e . plaque formation) is similar on saliva-coated cp-Ti and Ti-6Al-4V surfaces and indicate that both materials could be suitable for use as transgingival abutment or healing implant components . The same physico-chemical properties exhibited by saliva-coated cp-Ti and TA6V, as shown by the sessile drop method and the captive bubble method, could explain this similar bacterial colonisation . Therefore, higher values of total surface free energy of saliva-coated cp-Ti and saliva-coated TA6V samples (gamma(SV) approximately 65mJ/m(2)) were reported using the captive bubble method indicating a less hydrophobic character of these surfaces than with the sessile drop method (gamma(S) approximately 44.50mJ/m(2)) and consequently possible differences in oral bacterial retention according the theory described by Absolom et al . The number of adherent hydrophobic S . sanguinis cells was two-fold higher than that of hydrophilic S . constellatus cells . Our results confirm that physico-chemical surface properties of oral bacterial strains play a role in bacterial retention to implant materials in the presence of adsorbed salivary proteins.

Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi, 2004 Nov, 20(6), 754 - 6
{Effects of hypertonic saline on erythrocyte adherence function and bacterial infection of hemorrhagic shock rabbits.}; Li HC et al.; AIM: To explore the effect of hypertonic saline on the erythrocyte adherence function and bacterial infection of hemorrhagic shock rabbits . METHODS: 60 Japanese rabbits were randomly divided into 6 groups, 10 for each group . Artery catheterization and heparin were given to the rabbits in group 1 (sham shock group) . Hemorrhagic shock model was set up by bleeding resulting from carotid artery catheter in group 2 (normal saline group )and group 3 (hypertonic saline group) . 30 minutes after shock, the rabbits in group 1 and group 2 were treated with normal saline and balanced salt solution containing 1x10(9)/kg E.coli, respectively . And the rabbits in group 3 were treated with 75 g/L NaCl solution and balanced salt solution containing 1x10 (9)/kg E.coli . Then the survival rates of the rabbits in group 1-3 were observed . Rabbits in group 4-6 were same treatment as received, group 1-3, respectively, except that there was no E.coli in balanced salt solution . The erythrocyte immune adherence function of rabbits in group 4-6 were detected 5 hours after shock by RBC-C3bR and RBC-IC rosette forming assays . RESULTS: The survival rate of rabbits in hypertonic saline group was significantly higher than that in normal saline group.The RBC-C3bR rosette forming rate of the normal saline treated rabbits were pronouncedly decreased, while RBC-IC rosette forming rate was notably elevated, as compared with those of either sham shock group or hypertonic saline group(P<0.01) . Hypertonic saline markedly increased RBC C3bR rosette forming rate . CONCLUSION: The above findings suggest that hypertonic salt solution can remarkably improve the depressed erythrocyte immune adherence function and enhance the rabbit's resistance to E.coli challenge after hemorrhagic shock.

Insight, 2004 Jul-Sep, 29(3), 12 - 4
Bacterial contamination rate of eyedrops: comparison of a hospital and a private outpatient center in Kermanshah, Iran; Jalali R et al.; Bacterial contamination rate of eyedrops: comparison of a hospital and private outpatient ophthalmology centers of Kermanshah, Iran . Eye drops are sterile solutions with different clinical effects . Like any therapeutic medication, they should be administered using aseptic technique and stored in a way that prevents bacterial contamination . In our hospital and local private clinical settings, some cases of bacterial keratitis are thought to be due to eyedrops, which are used on multiple patients and at some point become contaminated . This study was done to compare the bacterial contamination rate in an educational hospital with private ophthalmic centers and attempt to identify the route of contamination and consequently, a method to resolve or reduce the problem.

J Appl Toxicol, 2004 Nov-Dec, 24(6), 415 - 8
Components of diesel exhaust particles differentially affect lung expression of cyclooxygenase-2 related to bacterial endotoxin; Inoue K et al.; We have reported previously that components of diesel exhaust particles (DEP) differently affect acute lung injury related to lipopolysaccharide (LPS) in mice . This study examined the effects of components of DEP on the lung expression of cyclooxygenase (COX)-1 and -2 in the presence or absence of LPS . ICR mice were divided into six experimental groups that received vehicle, LPS (2.5 mg kg(-1)), organic chemicals in DEP (DEP-OC) extracted with dichloromethane (4 mg kg(-1)), residual carbonaceous nuclei after the extraction (washed DEP: 4 mg kg(-1)), DEP-OC (4 mg kg(-1)) + LPS (2.5 mg kg(-1)) or washed DEP (4 mg kg(-1)) + LPS (2.5 mg kg(-1)) intratracheally . The expression of mRNA for both COXs in the lung was evaluated 4 h after the intratracheal administration . The magnitude of COX-1 mRNA expression was not altered in each group . The LPS treatment enhanced the COX-2 gene expression compared with vehicle treatment . Washed DEP combined with LPS further increased its expression compared with LPS alone . In contrast, combined treatment of DEP-OC with LPS decreased COX-2 gene expression compared with LPS alone . These results suggest that the residual carbonaceous nuclei of DEP predominantly enhance lung expression of COX-2 rather than the extracted organic chemicals from DEP in the presence of LPS, which is concomitant with the magnitude of acute lung injury in our previous study.

Nat Rev Microbiol, 2004 Dec, 2(12), 954 - 66
Bacterial redox sensors; Green J et al.; Redox reactions pervade living cells . They are central to both anabolic and catabolic metabolism . The ability to maintain redox balance is therefore vital to all organisms . Various regulatory sensors continually monitor the redox state of the internal and external environments and control the processes that work to maintain redox homeostasis . In response to redox imbalance, new metabolic pathways are initiated, the repair or bypassing of damaged cellular components is coordinated and systems that protect the cell from further damage are induced . Advances in biochemical analyses are revealing a range of elegant solutions that have evolved to allow bacteria to sense different redox signals.

Biochim Biophys Acta, 2004 Nov 11, 1694(1-3), 97 - 109
The role of lipids in membrane insertion and translocation of bacterial proteins; van Dalen A et al.; Phospholipids are essential building blocks of membranes and maintain the membrane permeability barrier of cells and organelles . They provide not only the bilayer matrix in which the functional membrane proteins reside, but they also can play direct roles in many essential cellular processes . In this review, we give an overview of the lipid involvement in protein translocation across and insertion into the Escherichia coli inner membrane . We describe the key and general roles that lipids play in these processes in conjunction with the protein components involved . We focus on the Sec-mediated insertion of leader peptidase . We describe as well the more direct roles that lipids play in insertion of the small coat proteins Pf3 and M13 . Finally, we focus on the role of lipids in membrane assembly of oligomeric membrane proteins, using the potassium channel KcsA as model protein . In all cases, the anionic lipids and lipids with small headgroups play important roles in either determining the efficiency of the insertion and assembly process or contributing to the directionality of the insertion process.

Mol Cell, 2004 Nov 19, 16(4), 563 - 74
Structure and function of an unusual family of protein phosphatases: the bacterial chemotaxis proteins CheC and CheX; Park SY et al.; In bacterial chemotaxis, phosphorylated CheY levels control the sense of flagella rotation and thereby determine swimming behavior . In E . coli, CheY dephosphorylation by CheZ extinguishes the switching signal . But, instead of CheZ, many chemotactic bacteria contain CheC, CheD, and/or CheX . The crystal structures of T . maritima CheC and CheX reveal a common fold unlike that of any other known protein . Unlike CheC, CheX dimerizes via a continuous beta sheet between subunits . T . maritima CheC, as well as CheX, dephosphorylate CheY, although CheC requires binding of CheD to achieve the activity of CheX . Structural analyses identified one conserved active site in CheX and two in CheC; mutations therein reduce CheY-phosphatase activity, but only mutants of two invariant asparagine residues are completely inactive even in the presence of CheD . Our structures indicate that the flagellar switch components FliY and FliM resemble CheC more closely than CheX, but attribute phosphatase activity only to FliY.

J Appl Microbiol, 2004, 97(6), 1123 - 31
Bacterial population dynamics and community structure in a pharmaceutical manufacturing water supply system determined by real-time PCR and PCR-denaturing gradient gel electrophoresis; Kawai M et al.; AIMS: To control bacteria in the pharmaceutical water supply system . METHODS AND RESULTS: Bacteria were enumerated by conventional culture method and fluorescent vital staining . Activated carbon treatment and storage in a tank provided favourable environments for bacterial growth . The bacterial population of the water in both the post-activated carbon treatment and the tank was analysed by denaturing gradient gel electrophoresis (DGGE) with PCR-amplified 16S rDNA fragments including V6, -7, and -8 regions . The bacterial community structure in activated carbon treated water was stable throughout the year . Several kinds of bacteria such as genus Aquaspirillum and Methylobacterium were found in the water after activated carbon treatment . The bacterial community structure was changed and other bacteria such as mycobacteria were detected after storage . Mycobacteria were quantified in water samples using real-time PCR targeting the 16S rDNA gene . Mycobacteria were also detected in tap water and their number was increased 10(3)-10(4)-fold higher after storage . CONCLUSION: These data suggest the importance of culture-independent methods for quality control of water used in pharmaceutical manufacturing . SIGNIFICANCE AND IMPACT OF THE STUDY: Critical steps and specified bacteria that should be controlled in the water supply system were recognized by culture-independent methods . These data will enable effective control of water used in the pharmaceutical industry.

Genetics . 2004 Nov 15; {Epub ahead of print}
Evidence for Abundant Slightly Deleterious Polymorphisms in Bacterial Populations; Hughes A; The nearly-neutral theory of molecular evolution predicts that slightly deleterious mutations subject to purifying selection are widespread in natural populations, particularly those of large effective population size . In order to test this hypothesis, the standardized difference between pairwise nucleotide difference and number of segregation sites (corrected for number of sequences) was estimated for 149 population data sets from 84 species of Bacteria . This quantity (Tajima's D statistic) was estimated separately for synonymous (Dsyn) and nonsynonymous (Dnon) polymorphisms . Dsyn was positive in 70% of data sets, and the overall median Dsyn (0.873) was positive . By contrast Dnon was negative in 68% of data sets, and the overall median Dnon (-0.656) was negative . The preponderance of negative values of Dnon is evidence that there are widespread rare nonsynonymous polymorphisms in the process of being eliminated by purifying selection, as predicted to occur in populations with large effective size by the nearly-neutral theory . The major exceptions to this trend were seen among surface proteins, particularly those of bacteria parasitic on vertebrates, which included a number of cases of polymorphisms apparently maintained by balancing selection.

Int J Syst Evol Microbiol . 2004 Nov;54(Pt 6):2439.
Proposal to list ATCC 43642 as the type strain of Leptospira interrogans in the Approved Lists of Bacterial Names . Request for an opinion; Landon S et al.; ATCC 23581(T) has been cited as the type strain of Leptospira interrogans since 1980 . In 1986, the Centers for Disease Control informed the ATCC that this strain was Leptospira interrogans serovar budapest, not serovar icterohaemorrhagiae as deposited originally . An authentic culture of the Leptospira interrogans serovar icterohaemorrhagiae RGA(T) strain was then submitted and assigned ATCC 43642, which was designated as the type strain of Leptospira interrogans in an article by Yasuda et al . {Yasuda et al . (1987) . Int J Syst Bacteriol 37, 407-415} . In this Request for an Opinion to the Judicial Commission, it is proposed that a correction be made in the Approved Lists of Bacterial Names to acknowledge ATCC 43642 as the type strain of Leptospira interrogans.

Langmuir, 2004 Nov 23, 20(24), 10625 - 9
Importance of molecular details in predicting bacterial adhesion to hydrophobic surfaces; Salerno MB et al.; Electrostatic and hydrophobic forces are generally recognized as important in bacterial adhesion . Current continuum models for these forces often wrongly predict measurements of bacterial adhesion forces . The hypothesis tested here is that even qualitative guides to bacterial adhesion often require more than continuum information about hydrophobic forces; they require knowledge about molecular details of the bacteria and substrate surface . In this study, four different strains of bacteria were adsorbed to silica surfaces hydrophobized with alkylsilanes . The thickness of the lipopolysaccharide layers varied on the different bacteria, and the lengths of the alkylsilane molecules were varied from experiment to experiment . Bacterial adhesion was assessed using column experiments and atomic force microscopy (AFM) experiments . Results show that hydrophobized surfaces have higher bacterial sticking coefficients and stronger adhesion forces than bare silica surfaces, as expected . However, adhesion decreased as the solution Debye length became longer than the alkylsilane, perhaps since the silane molecules could not "reach" the bacterial surface . Similarly, those bacteria with a long o-antigen layer had decreased adhesion, perhaps since the silane molecules could not reach surface-bound proteins on the bacteria . This study reveals that macroscopic measurements such as contact angle are not able to fully describe bacterial adhesion; rather, additional details such as the molecular length are required to predict adhesion.

Macromol Biosci, 2004 Nov 20, 4(11), 1039 - 52
Significant role of bacterial undecaprenyl diphosphate (C55-UPP) for rubber synthesis by Hevea latex enzymes; Rattanapittayaporn A et al.; Washed bottom fraction (BF) membrane-bound particles of centrifuged fresh Hevea latex were found to be very active in rubber biosynthesis (RB) . The washed BF membrane (WBM) showed higher RB activity and is strongly stimulated by anionic surfactants--more by DOC than SDS . WBM enzymes system can synthesize rubber either with allylic isoprenes (higher RB) or without (lower RB) . Washed rubber particles (WRP), used generally in RB assays, had very low RB activity compared to the much higher activity observed for WBM . Bacterial undecaprenyl diphoshate (C(55)-UPP) was very active allylic initiator for rubber synthesis by WBM . Comparisons of allylic UPP with the shorter ones (C(15)-FPP, C(20)-GGPP) showed that UPP was the most effective . WBM activity orders were UPP >> GGPP > FPP . The DOC activated WBM synthesized less polyprenyl intermediates (butanol extractable) but more final rubber product (toluene/hexane extract), different than FPP and GGPP . WBM enzymes were highly versatile in using diverse different allylics, but UPP was most preferable . WRP was found a little active for UPP with DOC, but still much lower than WBM . Rubber product analysis by RP-TLC with acetone/hexane solvent system showed that WBM was mostly rubber, but WRP was mainly the intermediates . Quantitative analysis showed that WBM labeled rubber was confined to the origin spot, different than WRP as mainly labeled intermediates . It was thus confirmed that the WBM plays the key role in RB functions, and not WRP as mostly reported . WBM served as the actual rubber synthesis site, and bacterial UPP was very good RB initiator.

Spine, 2004 Nov 15, 29(22), 2533 - 7
Bacterial spondylodiscitis in the patients with hemodialysis; Tsuchiya K et al.; STUDY DESIGN: Retrospective clinical and laboratory data analyses were performed on hemodialysis (HD) patients with bacterial spondylodiscitis . OBJECTIVES: The purpose of this study was to investigate clinical characteristics and related problems for the diagnosis and treatment of spondylodiscitis in patients on maintenance HD . Possible factors for the development of spondylodiscitis were also discussed . SUMMARY OF BACKGROUND DATA: Although bacterial spondylodiscitis is one of most serious complications that can occur in HD patients, few reports are seen describing its clinical course and treatment in HD patients . METHODS: A total of 9 HD patients were diagnosed as having bacterial spondylodiscitis at our institute . The onset of infection, characteristics of clinical symptoms, and clinical course were reviewed retrospectively . RESULTS: Latent form occurrence was most frequent, and only 1 in 9 cases presented high-grade fever at the beginning of treatment . Many complications were encountered both in conservatively treated and operated cases . Three patients were operated on, 1 of whom died 2 days after operation . Two of six patients in the conservatively treated group also died during the treatment period . CONCLUSIONS: The presence of bacterial spondylodiscitis must be considered when treating back pain of HD patients even when they are afebrile . Careful observation of general status in addition to local conditions is essential . Indication of operation should be considered carefully because of the poor general status and bone quality of HD patients . MRI, in addition to plain radiographs, was necessary to differentiate destructive spondylarthropathy from bacterial spondylodiscitis.

J Virol, 2004 Dec, 78(23), 13376 - 80
Oncogenicity of virulent Marek's disease virus cloned as bacterial artificial chromosomes; Petherbridge L et al.; Marek's disease virus (MDV) is an oncogenic alphaherpesvirus that induces T-cell lymphomas in poultry . We report the construction of bacterial artificial chromosome (BAC) clones of the highly oncogenic RB-1B strain by inserting mini-F vector sequences into the U(S)2 locus . MDV reconstituted from two BAC clones induced rapid-onset lymphomas similar to those induced by the wild-type virus . Virus reconstituted from another BAC clone that showed a 7.7-kbp deletion in the internal and terminal unique long repeat regions was nononcogenic, suggesting that the deleted region may be associated with oncogenicity . The generation of the oncogenic BAC clones of MDV is a significant step in unraveling the oncogenic determinants of this virus.

Eur J Obstet Gynecol Reprod Biol, 2004 Dec 1, 117(2), 222 - 6
Risk factors for bacterial vaginosis; Chiaffarino F et al.; OBJECTIVE: To analyse risk factors for bacterial vaginosis (BV) . STUDY DESIGN: We conducted a case-control study on risk factors for BV, in several first-level gynecological centers in Italy . Cases were women aged 18-70 years with confirmed diagnosis of BV (using test for proline iminopeptidase (PIP) activity) . Control were the first patients observed in the same center without any symptom suggesting vaginal infection, and a negative PIP activity test . A total of 476 cases and 450 controls entered the study . RESULTS: The number of sexual partners in the month before interview, but not the number of intercourses, was associated with an increased risk of BV . The risk of BV with vaginal douching or tight jeans/trousers once or more a week was 2.0 (95% CI 1.0-3.9) and 1.5 (95% CI 1.0-2.2), respectively, compared to never users . CONCLUSION: The findings are consistent with previous data and suggest that daily habits play an important role in risk of BV.

Biochem Biophys Res Commun, 2004 Dec 17, 325(3), 803 - 6
Redox sensing by Escherichia coli: effects of dithiothreitol, a redox reagent reducing disulphides, on bacterial growth; Kirakosyan G et al.; Escherichia coli is able to grow with a high rate under anaerobic conditions upon decrease in redox potential (E(h)) both either in slightly alkaline (pH 7.5) or acidic (pH 5.5) medium . Upon transition of E . coli MC4100 culture to stationary growth phase a decrease in E(h) from the positive values of +120 to +160 mV to the negative ones of -380 to -550 mV, and the H(2) production are observed at various pH . A redox reagent dl-dithiothreitol (DTT) in a concentration of 3mM reduces E(h) to the negative values, and increases a latent (lag) growth phase duration, as well as delays a logarithmic growth phase independently of pH . At alkaline and acidic pH the changes in membrane potential (DeltaPsi) are observed in the presence of 3mM DTT . K(+) uptake is recovered . At pH 5.5 the H(2) production is suppressed by DTT only in a higher concentration of 10 mM . The results suggest DTT effects that are in addition to the effects of E(h) . The mechanism of DTT action on bacterial growth might be intermediated through thiol group modulation of the membrane proteins, which is reflected as the generation of DeltaPsi as well as K(+) accumulation and the activity of the membrane-associated enzymes.

Dermatology, 2004, 209(4), 301 - 7
Chronic dermatomycoses of the foot as risk factors for acute bacterial cellulitis of the leg: a case-control study; Roujeau JC et al.; OBJECTIVE: To assess the role of foot dermatomycosis (tinea pedis and onychomycosis) and other candidate risk factors in the development of acute bacterial cellulitis of the leg . METHODS: A case-control study, including 243 patients (cases) with acute bacterial cellulitis of the leg and 467 controls, 2 per case, individually matched for gender, age (+/-5 years), hospital and admission date (+/-2 months) . RESULTS: Overall, mycology-proven foot dermatomycosis was a significant risk factor for acute bacterial cellulitis (odds ratio, OR: 2.4; p < 0.001), as were tinea pedis interdigitalis (OR: 3.2; p < 0.001), tinea pedis plantaris (OR: 1.7; p = 0.005) and onychomycosis (OR: 2.2; p < 0.001) individually . Other risk factors included: disruption of the cutaneous barrier, history of bacterial cellulitis, chronic venous insufficiency and leg oedema . CONCLUSIONS: Tinea pedis and onychomycosis were found to be significant risk factors for acute bacterial cellulitis of the leg that are readily amenable to treatment with effective pharmacological therapy . Copyright (c) 2004 S . Karger AG, Basel.

Chest, 2004 Nov, 126(5), 1645 - 55
Oral purified bacterial extracts in chronic bronchitis and COPD: systematic review; Steurer-Stey C et al.; BACKGROUND: Oral lyophilized extracts of bacteria species have been used since the early 1970s to improve symptoms and to prevent exacerbations in COPD patients . The value of these treatments, which are thought to be immunomodulating, is poorly understood . Our aim was to quantify the efficacy of oral bacteria extracts in patients with chronic bronchitis and COPD . DESIGN: Systematic review of randomized trials . DATA SOURCES: Electronic databases, bibliographies, and contact with authors and manufacturers . REVIEW METHODS: Randomized comparisons of oral purified bacterial (active) extracts with placebo or no treatment (control) were selected . Meta-analyses were performed using fixed and random-effects models, and the results were expressed as relative risk (RR), odds ratio (OR), number needed to treat for one to benefit (NNTB), or number needed to treat for one to be harmed (NNTH), with 95% confidence interval (CI) . RESULTS: Thirteen trials (1,971 patients), most of which were of low quality, tested OM-85BV (Broncho-Vaxom; OM Pharma; Geneva, Switzerland), LW-50020 (Luivac; ALTANA Pharma; Bad Homburg, Germany), or SL-04 . Two trials (731 patients) had appropriate methodologies and reported on exacerbations . The RR in favor of the oral bacterial extract (active) was 0.83 (95% CI, 0.55 to 1.25), and the NNTB was 15.4 (95% CI, 5.5 to infinity; NNTH, 27.5) . Five trials (591 patients) reported on observer-assessed improvement of symptoms RR in favor of active extracts was 0.57 (95% CI, 0.49 to 0.66), and the NNTB was 4 (95% CI, 2.8 to 5.4) . Two trials (n = 344), reported on patient-assessed improvement (RR, 0.44; 95% CI, 0.31 to 0.61) {NNTB, 4; 95% CI, 3.0 to 5.9} . In two trials (163 patients), the average duration of an exacerbation was shorter with the active extracts (weighted mean difference, -2.7 days; 95% CI, -3.5 to -1.8) . Itching or cutaneous eruptions was reported in 3.3% of patients (four trials; 802 patients) who received active extracts compared with 1.0% of control subjects (OR, 2.94 95% CI, 1.12 to 7.69) {NNTH, 50; 95% CI, 14 to 161} . Urologic problems (two trials; 671 patients) were reported in 8% of patients who received active extracts compared with 3.0% of control subjects (OR, 2.62; 95% CI, 1.35 to 5.11) {NNTH, 22; 95% CI, 10 to 61} . CONCLUSIONS: Oral purified bacterial extracts improve symptoms in patients with chronic bronchitis and COPD . There is not enough evidence to suggest that they prevent exacerbations . Cutaneous and urologic adverse effects are common.

FEMS Microbiol Rev, 2004 Nov, 28(5), 519 - 42
Molecular basis of bacterial resistance to chloramphenicol and florfenicol; Schwarz S et al.; Chloramphenicol (Cm) and its fluorinated derivative florfenicol (Ff) represent highly potent inhibitors of bacterial protein biosynthesis . As a consequence of the use of Cm in human and veterinary medicine, bacterial pathogens of various species and genera have developed and/or acquired Cm resistance . Ff is solely used in veterinary medicine and has been introduced into clinical use in the mid-1990s . Of the Cm resistance genes known to date, only a small number also mediates resistance to Ff . In this review, we present an overview of the different mechanisms responsible for resistance to Cm and Ff with particular focus on the two different types of chloramphenicol acetyltransferases (CATs), specific exporters and multidrug transporters . Phylogenetic trees of the different CAT proteins and exporter proteins were constructed on the basis of a multisequence alignment . Moreover, information is provided on the mobile genetic elements carrying Cm or Cm/Ff resistance genes to provide a basis for the understanding of the distribution and the spread of Cm resistance--even in the absence of a selective pressure imposed by the use of Cm or Ff.

Anal Chem, 2004 Nov 15, 76(22), 6693 - 7
Chip-based bioassay using bacterial sensor strains immobilized in three-dimensional microfluidic network; Tani H et al.; A whole-cell bioassay has been performed using Escherichia coli sensor strains immobilized in a chip assembly, in which a silicon substrate is placed between two poly(dimethylsiloxane) (PDMS) substrates . Microchannels fabricated on the two separate PDMS layers are connected via perforated microwells on the silicon chip, and thus, a three-dimensional microfluidic network is constructed in the assembly . Bioluminescent sensor strains mixed with agarose are injected into the channels on one of the two PDMS layers and are immobilized in the microwells by gelation . Induction of the firefly luciferase gene expression in the sensor strains can be easily carried out by filling the channels on the other layer with sample solutions containing mutagen . Bioluminescence emissions from each well are detected after injection of luciferin/ATP mixtures into the channels . In this assay format using two multichannel layers and one microwell array chip, the interactions between various types of samples and strains can be monitored at each well on one assembly in a combinatorial fashion . Using several genotypes of the sensor strains or concentrations of mitomycin C in this format, the dependence of bioluminescence on these factors was obtained simultaneously in the single screening procedure . The present method could be a promising on-chip format for high-throughput whole-cell bioassays.

J Eukaryot Microbiol, 2004 Sep-Oct, 51(5), 509 - 14
Bacterial endosymbionts of free-living amoebae; Horn M et al.; The occurrence of bacterial endosymbionts in free-living amoebae has been known for decades, but their obligate intracellular lifestyle hampered their identification . Application of the full cycle rRNA approach, including 16S rRNA gene sequencing and fluorescence in-situ hybridization with 16S rRNA-targeted oligonucleotide probes, assigned the symbionts of Acanthamoeba spp . and Hartmannella sp . to five different evolutionary lineages within the Proteobacteria, the Bacteroidetes, and the Chlamydiae, respectively . Some of these bacterial symbionts are most closely related to bacterial pathogens of humans, and it has been suggested that they should be considered potential emerging pathogens . Complete genome sequence analysis of a chlamydia-related symbiont of Acanthamoeba sp . showed that this endosymbiont uses similar mechanisms for interaction with its eukaryotic host cell as do the well-known bacterial pathogens of humans . Furthermore, phylogenetic analysis suggested that these mechanisms have been evolved by the ancestor of these amoeba symbionts in interplay with ancient unicellular eukaryotes.

J Allergy Clin Immunol, 2004 Nov, 114(5), 1051 - 4
Can bacterial endotoxin exposure reverse atopy and atopic disease?
Douwes J, Le Gros G, Gibson P, Pearce N.
Studies have shown that endotoxin exposure in childhood is associated with a reduced risk of atopy and atopic asthma . It is commonly assumed that these effects only occur in early life . However, recent epidemiologic studies suggest that immune deviation might take place throughout life . Assuming that the immune system is not fixed after the first years of life, we hypothesize that endotoxin exposure might not only inhibit the development of atopic sensitization and disease at any time throughout life but might also reverse this process . This novel extension of the hygiene hypothesis is primarily based on the indirect evidence of several epidemiologic observations showing a reduction in atopy in adults highly exposed to endotoxin that is unlikely to be explained by protective effects alone . In addition, some animal studies demonstrated the potential of endotoxin to downregulate pre-existing airway eosinophilia and hyperreactivity . However, there is currently little direct evidence that endotoxin might reverse atopy and allergic diseases . Observational studies and randomized trials to test this hypothesis could ultimately lead to the development of novel treatments for atopic diseases, such as allergic asthma, hay fever, and eczema.

Genomics, 2004 Dec, 84(6), 941 - 51
Genome physical mapping with large-insert bacterial clones by fingerprint analysis: methodologies, source clone genome coverage, and contig map quality; Xu Z et al.; Genome physical mapping with large-insert clones by fingerprint analysis is becoming an active area of genomics research . Here, we report two new capillary electrophoresis-based fingerprinting methods for genome physical mapping and the effects of different fingerprinting methods and source clone genome coverage on quality physical map construction revealed by computer simulations and laboratory experiments . It was shown that the manual sequencing gel-based two-enzyme fingerprinting method consistently generated larger and more accurate contigs, followed by the new capillary electrophoresis-based three-enzyme method, the new capillary electrophoresis-based five-enzyme (SNaPshot) method, the agarose gel-based one-enzyme method, and the automatic sequencing gel-based four-enzyme method, in descending order, when 1% or fewer questionable clones were allowed . Analysis of clones equivalent to 5x, 8x, 10x, and 15x genomes using the fingerprinting methods revealed that as the number of clones increased from 5x to 10x, the contig length rapidly increased for all methods . However, when the number of clones was increased from 10x to 15x coverage, the contig length at best increased at a lower rate or even decreased . The results will provide useful knowledge and strategies for effective construction of quality genome physical maps for advanced genomics research.

Nature, 2004 Dec 16, 432(7019), 917 - 21 Epub 2004 Nov 07.
Lipocalin 2 mediates an innate immune response to bacterial infection by sequestrating iron; Flo TH et al.; Although iron is required to sustain life, its free concentration and metabolism have to be tightly regulated . This is achieved through a variety of iron-binding proteins including transferrin and ferritin . During infection, bacteria acquire much of their iron from the host by synthesizing siderophores that scavenge iron and transport it into the pathogen . We recently demonstrated that enterochelin, a bacterial catecholate siderophore, binds to the host protein lipocalin 2 (ref . 5) . Here, we show that this event is pivotal in the innate immune response to bacterial infection . Upon encountering invading bacteria the Toll-like receptors on immune cells stimulate the transcription, translation and secretion of lipocalin 2; secreted lipocalin 2 then limits bacterial growth by sequestrating the iron-laden siderophore . Our finding represents a new component of the innate immune system and the acute phase response to infection.

Immunol Res, 2004, 30(3), 291 - 308
Osteoblast responses to bacterial pathogens: a previously unappreciated role for bone-forming cells in host defense and disease progression; Marriott I; Although the primary roles of osteoblasts are to synthesize the components of bone matrix and to regulate the activity of bone resorbing osteoclasts, there is growing realization that osteoblasts have an additional function during bone diseases, such as osteomyelitis . Based on our recent studies, we propose a novel role for osteoblasts during bacterial infections of bone, namely, the initiation and maintenance of inflammatory immune responses . In this article, we describe how these nonleukocytic cells can perceive bacterial pathogens of bone to initiate the production of an array of immune regulatory molecules . This pattern of expression is one that could promote the recruitment of leukocytes to sites of bacterial challenge, initiate antigen-specific activation of infiltrating cells, and facilitate the development of cell-mediated host responses to intracellular pathogens of bone tissue, thereby identifying this cell type as a previously unappreciated component in host responses.

Protein Eng Des Sel, 2004 Oct, 17(10), 731 - 9 Epub 2004 Nov 05.
Rapid isolation of high-affinity protein binding peptides using bacterial display; Bessette PH et al.; A robust bacterial display methodology was developed that allows the rapid isolation of peptides that bind to arbitrarily selected targets with high affinity . To demonstrate the utility of this approach, a large library (5 x 10(10) clones) was constructed composed of random 15-mer peptide insertions constrained within a flexible, surface exposed loop of the Escherichia coli outer membrane protein A (OmpA) . The library was screened for binding to five unrelated proteins, including targets previously used in phage display selections: human serum albumin, anti-T7 epitope mAb, human C-reactive protein, HIV-1 GP120 and streptavidin . Two to four rounds of enrichment (2-4 days) were sufficient to enrich peptide ligands having high affinity for each of the target proteins . Strong amino acid consensus sequences were apparent for each of the targets tested, with up to seven consensus residues . Isolated peptide ligands remained functional when expressed as insertional fusions within a monomeric fluorescent protein . This bacterial display methodology provides an efficient process for identifying peptide affinity reagents and should be useful in a variety of molecular recognition applications.

Bioinformatics . 2004 Nov 5; {Epub ahead of print}
ISYMOD: a knowledge warehouse for the identification, assembly and analysis of bacterial integrated systems; Chabalier J et al.; MOTIVATION: Complex biological functions emerge from interactions between proteins in stable supra-molecular assemblies and/or through transitory contacts . Most of the time protein partners of the assemblies are composed of one or several domains which exhibit different biochemical functions . Thus the study of cellular process requires the identification of different functional units and their integration in an interaction network; such complexes are referred to as integrated systems . In order to exploit with optimum efficiency the increased release of data, automated bioinformatics strategies are needed to identify, reconstruct and model such systems . For that purpose, we have developed a knowledge warehouse dedicated to the representation and acquisition of bacterial integrated systems involved in the exchange of the bacterial cell with its environment . RESULTS: ISYMOD is a knowledge warehouse that consistently integrates in the same environment the data and the methods used for their acquisition . This is achieved through the construction of i) a domain knowledge base (DKB) devoted to the storage of the knowledge about the systems, their functional specificities, their partners and how they are related, and ii) a methodological knowledge base (MKB) which depicts the task layout used to identify and reconstruct functional integrated systems . Instantiation of the DKB is obtained by solving the tasks of the MKB, whereas some tasks need instances of the DKB to be solved . AROM, an object-based knowledge representation system, has been used to design the DKB, and its task manager, AROMTASKS, for developing the MKB . In this study two integrated systems, ABC transporters and two component systems, both involved in adaptation processes of a bacterial cell to its biotope, have been used to evaluate the feasibility of the approach.

Biochem Biophys Res Commun, 2004 Dec 10, 325(2), 467 - 78
Three-base periodicity patterns and self-similarity in whole bacterial chromosomes; Lopez-Villasenor I et al.; It has been reported that in a collection of mRNAs the triplets GhN or RNY had a higher propensity to be separated by either three/six/nine, etc., bases than by two/four/five, etc., bases . This has been called three-base periodicity (TBP) . In this work the frequency distribution of distances (FDDs) for all triplets in the Borrelia burgdorferi chromosome and selected triplets in other model sequences were determined . The FDDs produced oscillatory decaying patterns with TBP for most triplets and not only for those encompassed by the above formulas . Furthermore, we also found TBP for di- and mononucleotides . However, TBP was not observed for intergenic regions, sequences with a low content of coding regions or when the coding potential of sequences was disrupted by base shuffling . Excluding closely related species the FDDs between bacterial genomes were different and appeared characteristic of the analyzed genome . FDDs also showed self-similarity, since 1Mb sequences rendered FDDs that were very similar to those for the entire sequence.

Curr Biol, 2004 Nov 9, 14(21), 1929 - 34
Identification of bacterial muramyl dipeptide as activator of the NALP3/cryopyrin inflammasome; Martinon F et al.; Activation of caspase-1 and subsequent processing and secretion of the pro-inflammatory cytokine IL-1beta is triggered upon assembly of the inflammasome complex . It is generally believed that bacterial lipopolysaccharides (LPS) are activators of the inflammasome through stimulation of Toll-like receptor 4 (TLR4) . Like TLRs, NALP3/Cryopyrin, which is a key component of the inflammasome, contains Leucine-Rich-Repeats (LRRs) . LRRs are frequently used to sense bacterial components, thus raising the possibility that bacteria directly activate the inflammasome . Here, we show that bacterial peptidoglycans (PGN), but surprisingly not LPS, induce NALP3-mediated activation of caspase-1 and maturation of proIL-1beta . Activation is independent of TLRs because the PGN degradation product muramyl dipeptide (MDP), which is not sensed by TLRs, is the minimal-activating structure . Macrophages from a patient with Muckle-Wells syndrome, an autoinflammatory disease associated with mutations in the NALP3/Cryopyrin gene, show increased IL-1beta secretion in the presence of MDP . The activation of the NALP3-inflammasome by MDP may be the basis of the potent adjuvant activity of MDP.

Structure (Camb), 2004 Nov, 12(11), 2037 - 48
Solution structure of the bacterial frataxin ortholog, CyaY: mapping the iron binding sites; Nair M et al.; CyaY is the bacterial ortholog of frataxin, a small mitochondrial iron binding protein thought to be involved in iron sulphur cluster formation . Loss of frataxin function leads to the neurodegenerative disorder Friedreich's ataxia . We have solved the solution structure of CyaY and used the structural information to map iron binding onto the protein surface . Comparison of the behavior of wild-type CyaY with that of a mutant indicates that specific binding with a defined stoichiometry does not require aggregation and that the main binding site, which hosts both Fe(2+) and Fe(3+), occupies a highly anionic surface of the molecule . This function is conserved across species since the corresponding region of human frataxin is also able to bind iron, albeit with weaker affinity . The presence of secondary binding sites on CyaY, but not on frataxin, hints at a possible polymerization mechanism . We suggest mutations that may provide further insights into the frataxin function.

Structure (Camb), 2004 Nov, 12(11), 1923 - 4
First structural glimpse at a bacterial Ser/Thr protein phosphatase; Alzari PM; In this issue of Structure, we describe the crystal structure of the Ser/Thr protein phosphatase PstP from Mycobacterium tuberculosis, opening new perspectives to understand the putative roles of "eukaryotic-like" signaling elements in bacteria.

FEBS Lett, 2004 Nov 5, 577(1-2), 265 - 9
Contribution of the active site aspartic acid to catalysis in the bacterial neuraminidase from Micromonospora viridifaciens; Watson JN et al.; A recombinant D92G mutant sialidase from Micromonospora viridifaciens has been cloned, expressed and purified . Kinetic studies reveal that the replacement of the conserved aspartic acid with glycine results in a catalytically competent retaining sialidase that possesses significant activity against activated substrates . The contribution of this aspartate residue to the free energy of hydrolysis for natural substrates is greater than 19 kJ/mol . The three dimensional structure of the D92G mutant shows that the removal of aspartic acid 92 causes no significant re-arrangement of the active site, and that an ordered water molecule substitutes for the carboxylate group of D92.

Brain Res, 2004 Dec 3, 1028(2), 233 - 7
Effect of subdiaphragmatic vagotomy on bacterial DNA-induced IL-1beta expression in the mouse hypothalamus; Ono A et al.; We investigated whether bacterial DNA (CpG-DNA)-induced IL-1beta expression in the mouse hypothalamus is mediated via afferent vagus nerve . Subdiaphragmatic vagotomy did not modify the CpG-DNA (i.p.)-induced IL-1beta expression in the hypothalamus, indicating that CpG-DNA-induced IL-1beta expression is independent of the afferent vagus nerve originating from the subdiaphragmatic organs . On the other hand, we observed the Toll-like receptor 9 mRNA expression in the hypothalamus, suggesting that circulating CpG-DNA acts directly in the brain.

Oecologia, 2005 Jan, 142(3), 428 - 39 Epub 2004 Oct 30.
Within-trophic group interactions of bacterivorous nematode species and their effects on the bacterial community and nitrogen mineralization; Postma-Blaauw MB et al.; Knowledge of the interactions between organisms within trophic groups is important for an understanding of the role of biodiversity in ecosystem functioning . We hypothesised that interactions between bacterivorous nematodes of different life history strategies would affect nematode population development, bacterial community composition and activity, resulting in increased N mineralization . A microcosm experiment was conducted using three nematode species (Bursilla monhystera, Acrobeloides nanus and Plectus parvus) . All the nematode species interacted with each other, but the nature and effects of these interactions depended on the specific species combination . The interaction between B . monhystera and A . nanus was asymmetrically competitive (0,-), whereas that between B . monhystera and P . parvus, and also A . nanus and P . parvus was contramensal (+, -) . The interaction that affected microcosm properties the most was the interaction between B . monhystera and P . parvus . This interaction affected the bacterial community composition, increased the bacterial biomass and increased soil N mineralization . B . monhystera and P . parvus have the most different life history strategies, whereas A . nanus has a life history strategy intermediate to those of B . monhystera and P . parvus . We suggest that the difference in life history strategies between species of the same trophic group is of importance for their communal effect on soil ecosystem processes . Our results support the idiosyncrasy hypothesis on the role of biodiversity in ecosystem functioning.

Biochem Biophys Res Commun, 2004 Dec 3, 325(1), 1 - 2
Correspondence regarding Bharanidharan et al., "Correlations between nucleotide frequencies and amino acid composition in 115 bacterial species"; Najafabadi HS et al.; Bharanidharan et al . {Biochem . Biophys . Res . Commun . 315 (2004) 1097-1103} claimed that the frequencies of most amino acids are determined by the dinucleotide composition of the genome . Here, regarding a methodological problem in their work, it is suggested that the standard deviations of amino acid frequencies should be determined to indicate how significant a certain deviation from the predicted frequency is . Furthermore, using a different method that is expected to be more reliable, we suggest that the dinucleotide composition cannot explain the observed frequencies of most amino acids, and the deviations of amino acid frequencies from what dinucleotide composition predicts are larger than to be expected by chance.

Proc Natl Acad Sci U S A, 2004 Nov 16, 101(46), 16174 - 9 Epub 2004 Nov 16.
Transition state and encounter complex for fast association of cytochrome c2 with bacterial reaction center; Miyashita O et al.; Electrostatic interactions strongly enhance the electron transfer reaction between cytochrome (Cyt) c(2) and reaction center (RC) from photosynthetic bacteria, yielding a second-order rate constant, k(2) approximately 10(9) s(-1).M(-1), close to the diffusion limit . The proposed mechanism involves an encounter complex (EC) stabilized by electrostatic interactions, followed by a transition state (TS), leading to the bound complex active in electron transfer . The effect of electrostatic interactions was previously studied by Tetreault et al . {Tetreault, M., Cusanovich, M., Meyer, T., Axelrod, H . & Okamura, M . Y . (2002) Biochemistry 41, 5807-5815} by measuring k(2) for RC and Cyt molecules with modified charged residues at the binding interface . The present work is a computational analysis of this kinetic study to determine the ensemble of configurations of the TS and EC . Changes in the TS energies due to different mutations were compared with differences in the calculated electrostatic energies for a wide range of Cyt/RC configurations . The TS ensemble, obtained from structures having the highest correlation coefficients in the comparison with experimental data, has the Cyt displaced by approximately 10 A from its position in x-ray crystal structure, close to the average position of the EC ensemble, with strong electrostatic interactions between Cyt on the M subunit side of the RC surface . The heme of the Cyt is oriented toward Tyr L162 on the RC, the tunneling contact in the bound final state on the RC . The similarity between the structures of the EC, TS, and bound state can account for the rapid rate of association responsible for fast diffusion-controlled electron transfer.

Brain Res Mol Brain Res, 2004 Nov 4, 130(1-2), 23 - 9
Bacterial endotoxin induces IL-20 expression in the glial cells; Hosoi T et al.; The regulatory mechanisms leading to IL-20 expression during infection have not been elucidated . In the present study, we found that bacterial lipopolysaccharide (LPS) induced IL-20 expression in the primary cultured glial cells and RAW264.7 macrophage cell line . Pretreatment with protein synthesis inhibitor puromycin or cycloheximide failed to inhibit the expression of IL-20, suggesting that the expression was not dependent on de novo protein synthesis . Myeloid differentiation factor 88 (MyD88) is an important adaptor molecule for Toll-like receptor signaling . We observed complete inhibition of LPS-induced expression of IL-20 in the primary cultured glial cells prepared from MyD88-deficient mice . Furthermore, a p38 MAP kinase inhibitor, SB203580, inhibited LPS-induced expression of IL-20 mRNA . LPS-induced p38 MAP kinase phosphorylation was delayed in MyD88-deficient glial cells . Therefore, it is suggested that LPS induces IL-20 expression through MyD88-p38-dependent mechanisms . As dexamethasone inhibited LPS-induced IL-20 expression, the expression of IL-20 is regulated by a negative feedback loop mediated through glucocorticoids . Therefore, it is suggested that IL-20 may play a crucial role in inflammatory conditions in the brain.

Biochim Biophys Acta, 2004 Nov 3, 1666(1-2), 88 - 104
Bacterial osmosensing: roles of membrane structure and electrostatics in lipid-protein and protein-protein interactions; Poolman B et al.; Bacteria act to maintain their hydration when the osmotic pressure of their environment changes . When the external osmolality decreases (osmotic downshift), mechanosensitive channels are activated to release low molecular weight osmolytes (and hence water) from the cytoplasm . Upon osmotic upshift, osmoregulatory transporters are activated to import osmolytes (and hence water) . Osmoregulatory channels and transporters sense and respond to osmotic stress via different mechanisms . Mechanosensitive channel MscL senses the increasing tension in the membrane and appears to gate when the lateral pressure in the acyl chain region of the lipids drops below a threshold value . Transporters OpuA, BetP and ProP are activated when increasing external osmolality causes threshold ionic concentrations in excess of about 0.05 M to be reached in the proteoliposome lumen . The threshold activation concentrations for the OpuA transporter are strongly dependent on the fraction of anionic lipids that surround the cytoplasmic face of the protein . The higher the fraction of anionic lipids, the higher the threshold ionic concentrations . A similar trend is observed for the BetP transporter . The lipid dependence of osmotic activation of OpuA and BetP suggests that osmotic signals are transmitted to the protein via interactions between charged osmosensor domains and the ionic headgroups of the lipids in the membrane . The charged, C-terminal domains of BetP and ProP are important for osmosensing . The C-terminal domain of ProP participates in homodimeric coiled-coil formation and it may interact with the membrane lipids and soluble protein ProQ . The activation of ProP by lumenal, macromolecular solutes at constant ionic strength indicates that its structure and activity may also respond to macromolecular crowding . This excluded volume effect may restrict the range over which the osmosensing domain can electrostatically interact . A simplified version of the dissociative double layer theory is used to explain the activation of the transporters by showing how changes in ion concentration could modulate interactions between charged osmosensor domains and charged lipid or protein surfaces . Importantly, the relatively high ionic concentrations at which osmosensors become activated at different surface charge densities compare well with the predicted dependence of 'critical' ion concentrations on surface charge density . The critical ion concentrations represent transitions in Maxwellian ionic distributions at which the surface potential reaches 25.7 mV for monovalent ions . The osmosensing mechanism is qualitatively described as an "ON/OFF switch" representing thermally relaxed and electrostatically locked protein conformations.

Akush Ginekol (Sofiia), 2004, 43 Suppl 2, 26 - 7
{Bacterial vaginosis in pregnant women--treatment with clindamycin}; Damianov L et al.; The authors discuss one of the most frequently founded cause of spontaneous abortions and prematurity birth--the bacterial vaginosis . The diagnostics is easy and not expensive . In the complex of health's caries it is necessary to include and the prophylaxis of diagnostics and harmless and efficient treatment with local drug as example "Dalacin V".

Ginekol Pol, 2004 Jul, 75(7), 538 - 44
{Life style, Chlamydia trachomatis infection, bacterial vaginosis and their impact on the frequency of cervical lesions}; Zbroch T et al.; OBJECTIVES: Sexually transmitted infectious factors attained unquestionable importance in the initiation of the cervical intraepithelial neoplasia . The aim of this study was to evaluate the incidence and impact of Bacterial vaginosis, Chlamydia trachomatis infection in accordance to a life style on clinically and cytologically evaluated cervical lesions . DESIGN/METHODS: Seventy-two young women without any symptoms were included to the study . Women underwent pelvic examination when cervical smears for cytology and Ch.tr . were taken and BV tests were performed . Presence of Chlamydia was estimated by direct immunofluorescent method . Subjects included to the study provided information concerning life style, and gynecological complaints . RESULTS: In both BV(+) or Ch.tr.(+) women, abnormal PapTest results were more frequently observed . All those three factors correlated with declared over 5 lifetime sexual partners . Ch.tr . infection correlated with BC pills using, cigarette smoking and presence of the cervical lesions evaluated as glandular ectopy . Abnormal PapTest result was obtained in 12 subjects . Two, the most abnormal cases were described as LSIL and confirmed by direct biopsy as CIN 1, also with coexistence of C . trachomatis infection and positive for BV . CONCLUSIONS: Ch.tr . infection seems to affect more frequently sexually active, smoking, young women using BC pills, with presence of cervical lesion described as clinically unsuspected glandular ectopy, although with occasionally cytological abnormal findings.

Environ Mol Mutagen, 2004, 44(5), 441 - 7
Examination of the potential genotoxicity of pure capsaicin in bacterial mutation, chromosome aberration, and rodent micronucleus tests; Proudlock R et al.; There is widespread dietary exposure to capsaicin in the form of chili peppers, while capsaicin's analgesic qualities have led to increased use of a topical herbal remedy in various impure forms . Most recently, injection of pure capsaicin has been proposed as a means of relieving a variety of debilitating diseases, in which case tissues would receive relatively high and direct exposure . The purpose of the present study, where a series of standard assays were performed in accordance with the Organisation for Economic Cooperation and Development guidance, was to clarify earlier conflicting reports concerning potential genotoxicity of capsaicin prior to administering it to patients in an injectable form . The results confirm the absence of genotoxic activity of high-purity capsaicin in the bacterial mutation and chromosome aberration tests . In addition, no evidence of cytotoxicity or genotoxicity was seen in the rat bone marrow micronucleus test, where systemic exposure to pure capsaicin was achieved using the subcutaneous route and a rising dose toleration protocol . It is concluded that pure capsaicin is not active in the standard battery of genotoxicity assays recommended by the International Conference on Harmonisation for evaluation of new medicines; earlier reported in vitro genotoxic activity is probably associated with mutagenic impurities in commercial grades of the material . Environ . Mol . Mutagen . 2004 . (c) 2004 Wiley-Liss, Inc.

Nat Cell Biol, 2004 Nov, 6(11), 1026 - 33
Subversion of phosphoinositide metabolism by intracellular bacterial pathogens; Pizarro-Cerda J et al.; Phosphoinositides are short-lived lipids, whose production at specific membrane locations in the cell enables the tightly controlled recruitment or activation of diverse cellular effectors involved in processes such as cell motility or phagocytosis . Bacterial pathogens have evolved molecular mechanisms to subvert phosphoinositide metabolism in host cells, promoting (or blocking) their internalization into target tissues, and/or modifying the maturation fate of their proliferating compartments within the intracellular environment.

J Bacteriol, 2004 Nov, 186(22), 7618 - 25
Continuous control in bacterial regulatory circuits; Batchelor E et al.; We show that for two well-characterized regulatory circuits in Escherichia coli, Tn10 tetracycline resistance and porin osmoregulation, the transcriptional outputs in individual cells are graded functions of the applied stimuli . These systems are therefore examples of naturally occurring regulatory circuits that exhibit continuous control of transcription . Surprisingly, however, we find that porin osmoregulation is open loop; i.e., the porin expression level does not feed back into the regulatory circuit . This mode of control is particularly interesting for an organism such as E . coli, which proliferates in diverse environments, and raises important questions regarding the biologically relevant inputs and outputs for this system.

J Bacteriol, 2004 Nov, 186(22), 7499 - 507
Characteristics of zinc transport by two bacterial cation diffusion facilitators from Ralstonia metallidurans CH34 and Escherichia coli; Anton A et al.; CzcD from Ralstonia metallidurans and ZitB from Escherichia coli are prototypes of bacterial members of the cation diffusion facilitator (CDF) protein family . Expression of the czcD gene in an E . coli mutant strain devoid of zitB and the gene for the zinc-transporting P-type ATPase zntA rendered this strain more zinc resistant and caused decreased accumulation of zinc . CzcD, purified as an amino-terminal streptavidin-tagged protein, bound Zn2+, Co2+, Cu2+, and Ni2+ but not Mg2+, Mn2+, or Cd2+, as shown by metal affinity chromatography . Histidine residues were involved in the binding of 2 to 3 mol of Zn2+ per mol of CzcD . ZitB transported 65Zn2+ in the presence of NADH into everted membrane vesicles with an apparent Km of 1.4 microM and a Vmax of 0.57 nmol of Zn2+ min(-1) mg of protein(-1) . Conserved amino acyl residues that might be involved in binding and transport of zinc were mutated in CzcD and/or ZitB, and the influence on Zn2+ resistance was studied . Charged or polar amino acyl residues that were located within or adjacent to membrane-spanning regions of the proteins were essential for the full function of the proteins . Probably, these amino acyl residues constituted a pathway required for export of the heavy metal cations or for import of counter-flowing protons.

Obstet Gynecol, 2004 Nov, 104(5 Pt 1), 931 - 2
Treatment of recurrent bacterial vaginosis with tinidazole; Baylson FA et al.; BACKGROUND: Recurrent bacterial vaginosis is a difficult clinical condition . In women with recurrent bacterial vaginosis, relapses are common, even after prolonged courses of maintenance therapy . Because of its spectrum of activity, tinidazole was used in a patient with recurrent bacterial vaginosis . CASE: A 23-year-old woman taking oral contraceptives had a single sexual partner . She was treated for recurrent bacterial vaginosis with multiple courses of metronidazole gel 0.75%, including regimens of maintenance therapy . The patient experienced repeated recurrences shortly after stopping treatment . A single course of oral tinidazole resulted in a prolonged period where she was free of bacterial vaginosis . CONCLUSION: Treatment options for recurrent bacterial vaginosis are currently limited . Tinidazole may be a useful option in women with recurrent bacterial vaginosis.

Anal Chem, 2004 Nov 1, 76(21), 6207 - 13
Magnetic cell separation using antibody binding with protein a expressed on bacterial magnetic particles; Kuhara M et al.; Bacterial magnetic particles (BacMPs) are efficient platforms of proteins for surface display systems . In this study, mononuclear cells from peripheral blood were separated using BacMPs expressing protein A on the BacMP membrane surface (protein A-BacMPs), which were complexed with the Fc fragment of anti-mouse IgG antibody . The procedure of positive selection involves incubation of mononuclear cells and mouse monoclonal antibodies against different cell surface antigens (CD8, CD14, CD19, CD20) prior to treatment with protein A-BacMP binding with rabbit anti-mouse IgG secondary antibodies . Flow cytometric analysis showed that approximately 97.5 +/- 1.7% of CD19(+) and CD20(+) cells were involved in the positive fraction after magnetic separation . The ratio of the negative cells in the negative fraction was approximately 97.6 +/-1.4% . This indicates that CD19(+) and CD20(+) cells can be efficiently separated from mononuclear cells . Stem cell marker (CD34) positive cells were also separated using protein A-BacMP binding with antibody . May-Grunwald Giemsa stain showed a high nuclear/cytoplasm ratio, which indicates a typical staining pattern of stem cells . The separated cells had the capability of colony formation as hematopoietic stem cells . Furthermore, the inhibitory effect of magnetic cell separation on CD14(+) cells was evaluated by measurement of cytokine in the culture supernatant by ELISA when the cells were cultured with or without lipopolysaccharide (LPS) . The induction of IL1-beta, TNFalpha, and IL6 was observed in the presence of 1 ng/mL LPS in all fractions . On the other hand, in the absence of LPS, BacMPs had little immunopotentiation to CD14(+) cells as well as that of artificial magnetic particles, although TNFalpha and IL6 were slightly induced in the absence of LPS in the positive fraction.

Huan Jing Ke Xue, 2004 Jul, 25(4), 143 - 8
{Toxic-effects of acetochlor, methamidophos and their combination on bacterial amount and population richness at molecular levels in agricultural black soils}; Zhang HW et al.; Bacterial amount and population richness in agricultural black soil under the stress of acetochlor, methamidophos and their combination were analyzed by CFU and 16S rDNA-PCR DGGE . Results showed that both of acetochlor and methamidophos had acute toxic effects on the growth of bacteria in agricultural black soil; Growth of free-living nitrogen fixing bacteria was inhibited badly by methamidophos, but stimulated greatly by acetochlor . The joint inhibitory effects of all combinations at different concentration between methamidophos and acetochlor on free-living nitrogen fixing bacteria were severer than each of their singal factors,which indicate the significant joint toxic effects between acetochlor and methamidophos on free-living nitrogen fixing bacteria in tested soil . Bacterial population diversity were decreased and the structure were changed respectively at different levels according to their concentration and combinations . Some bacterial species were diminished, but some others were accumulated under the stress of two agrochemicals and their combinations.

Przegl Lek, 2004, 61(5), 514 - 7
{The role of human and bacterial heat shock proteins in inflammatory and immunological mechanisms of atherosclerosis}; Rajtar R et al.; Atherosclerosis remains the leading cause of morbidity and mortality in many countries . Recent studies have demonstrated that the pathogenesis of atherosclerosis involves not only lipid deposition, but also the inflammatory process . The heat shock proteins (HSPS) are expressed in normal cells but their expression is enhanced by a number of different stress factors including heat and ischaemia . They play important roles in chaperoning the "folding" of other proteins and in protein degradation.

Genes Genet Syst, 2004 Aug, 79(4), 251 - 3
Construction of a bacterial artificial chromosome library from the inshore hagfish, Eptatretus burgeri: A resource for the analysis of the agnathan genome; Suzuki T et al.; The jawless fish occupy an important phylogenetic position for understanding the evolution of body plans, the origin of adaptive immunity and genome evolution in chordates . We describe here the construction of a large-insert bacterial artificial chromosome (BAC) library from the inshore hagfish, Eptatretus burgeri . The BAC library contains 93,978 clones with an average insert size of 100 kb and is estimated to represent threefold genome-equivalent coverage . The library was organized in three-dimensional pools to facilitate screening by PCR . We have screened this library by PCR and isolated several BAC clones; the average number of positive clones was compatible with the estimated genome coverage of the library . This BAC library, constructed for the first time from the jawless fish, should serve as a useful resource for the scientific community.

J Nutr, 2004 Nov, 134(11), 3047 - 53
Decreased protein accretion in pigs with viral and bacterial pneumonia is associated with increased myostatin expression in muscle; Escobar J et al.; Chronic respiratory infections reduce growth in pigs but protein accretion (PA) during an ongoing multifactorial respiratory infection has not been determined, and the mechanisms underlying growth inhibition are largely unknown . The objectives of this study were to determine whether viral and bacterial pneumonia in young pigs decrease PA, increase serum IL-1beta and IL-6, and increase myostatin (MSTN) mRNA in biceps femoris and triceps muscles . Mycoplasma hyopneumoniae (Mh) or medium was given intratracheally at 4 wk of age, Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) or medium was given intranasally at 6 wk of age, and pigs were killed 7 or 14 d after PRRSV inoculation for body composition analysis . PRRSV but not Mh induced a marked increase (P < 0.01) in IL-1beta, IL-6, and MSTN mRNA and a decrease (P < 0.01) in food intake, daily weight gain, PA, and lipid accretion . PRRSV also reduced (P < 0.01) myofiber area in the biceps femoris . Food intake, weight gain, PA, and weight of biceps femoris and triceps muscles were negatively correlated (r = -0.4 to -0.8, P < 0.05) with serum IL-1beta and IL-6 and with MSTN mRNA in muscle . These results suggest that the magnitude of increases in inflammatory cytokines during a respiratory infection may be predictive of decreases in PA and growth . They further suggest that during infection growth of skeletal muscle is limited in part by myostatin.

J Drug Target, 2004 Jun, 12(5), 281 - 8
Chitosan-DNA nanoparticles: effect on DNA integrity, bacterial transformation and transfection efficiency; Bozkir A et al.; While somatic gene therapy has the potential to treat many genetic disorders, recent clinical trials suggest that an efficient and safe delivery vehicle for successful gene therapy is lacking . The current study examines the influence of two different preparation (the solvent evaporation method and the complex coacervation method) methods on the encapsulation of a model plasmid with chitosan . The ability of different molecular weights of chitosan to form nanoparticles with a plasmid, and particulated polymers to stabilize a plasmid in a supercoiled form, were examined by agarose gel electrophoresis . Protection of encapsulated pDNA offered by these nanoparticles from nuclease attack was confirmed by assessing degradation in the presence of DNase I, and the transformation of the plasmids with incubated nanoparticles were examined by beta-galactosidase assay . Model pDNA existed as a mixture of both supercoiled (84.2%) and open circular (15.8%) forms . Our results demonstrated that supercoiled forms decreased while open circular forms and fragmented linear forms increased during the preparation of formulations . F1 formulation prepared by the complex coacervation method protected the supercoiled form of pDNA effectively . There weren't any significant changes in nanoparticle size and zeta potential values at pH 5.5 for a period of 3 months, but differences in particle sizes were observed after lyophilization with a cryoprotective agent . The efficiency of nanoparticles mediated transformation to Escherichia coli cells was significantly higher than naked DNA or poly-L-lysine (PLL)-DNA polycation complexes . The transfection studies were performed in COS-7 cells . A 3-fold increase in gene expression was produced by nanoparticles as compared to the same amount of naked plasmid DNA (pDNA) . These observations suggest that formulations with high molecular weight (HMW) chitosan can be an effective non-viral method of gene vector in animal studies.

J Obstet Gynaecol, 1998, 18(6), 572 - 4
Bacterial vaginosis and cervical intraepithelial neoplasia-cause or coincidence?
Uthayakumar S.
Evidence regarding a causal relationship between bacterial vaginosis and cervical intraepithelial neoplasia has so far been incomplete and conflicting . To determine whether bacterial vaginosis is associated with cervical intraepithelial neoplasia a retrospective study was conducted at the Genitourinary Medicine Clinic at Southlands Hospital, Shoreham-by-Sea, UK . Three hundred patients who presented to the clinic with a first diagnosis of genital warts in the absence of other sexually transmitted diseases were recruited . Results of cervical cytology and where abnormal, histology on colposcopically directed punch biopsies were collected . Bacterial vaginosis was diagnosed by the detection of clue cells on Gram-staining of a high vaginal swab, positive amine test, vaginal pH above 4.5 and the presence of characteristic vaginal discharge . Odds ratio showed an increased prevalence of cervical intraepithelial neoplasia associated with bacterial vaginosis . The results suggest that a prospective cross sectional study should be performed to formally test the hypothesis that bacterial vaginosis predisposes to cervical intraepithelial neoplasia.

J Obstet Gynaecol, 1997, 17(4), 383 - 5
Anaerobic (bacterial) vaginosis and premalignant disease of the cervix; W Barrington D Linton A O Leary A Blackwell J Brick And J P Calvert J; Summary Nitrosamines are carcinogenic substances found in cigarette smoke, and it is known that female smokers have an increased risk of cervical carcinoma and premalignant change . Nitrosamines may also be formed due to the combination of amines and nitrites in an acidic medium . This study has shown a statistically significant association between anaerobic vaginosis which produce amines and cervical intraepithelial neoplasia 2 and 3 . In addition nitrate reducing organisms are found in the acidic lower genital tract in a significant number of cases . It is therefore theoretically possible that nitrosamines may be an important agent in the development of premalignant disease of the cervix.

Aten Primaria, 2004 Oct 31, 34(7), 360 - 5
{Factors of risk of bacterial vaginosis}; Gonzalez-Pedraza Aviles A et al.; OBJECTIVES: To recognise factors in the host that might condition the appearance of the bacterial vaginosis (BV) syndrome, whether gynae-obstetrical factors, habits of sexual conduct, hygiene, or other factors . DESIGN: Cross-sectional, observational study . SETTING: The study was conducted from January 2002 to June 2003 in the Primary Care Dr . Jose Castro Villagrana Community Health Centre at Tlalpan, Mexico City . PARTICIPANTS: 968 patients with an active sexual life who had not taken antibiotics for at least 15 days before the study and who were not menstruating at the moment of taking a swab, 859 of whom had a diagnosis of cervico-vaginitis and 109 had no symptoms . MAIN MEASUREMENTS: Confidential questionnaire and a cervical-vaginal culture . The Amsel criteria were used to make the diagnosis of bacterial vaginosis . RESULTS: There was 32.9% prevalence of BV . There was a statistically significant association with factors such as age, start of active sexual life, the number of sexual relations per week, the number of sexual partners, and pregnancy . CONCLUSIONS: Bacterial vaginosis is the main cause of infectious processes in the vagina . Its appearance appears to be linked to factors involving sexual transmission . Interventions to reduce its prevalence and complications are recommended.

Nature, 2004 Oct 28, 431(7012), 1062 - 8
Structure of the bacterial flagellar hook and implication for the molecular universal joint mechanism; Samatey FA et al.; The bacterial flagellum is a motile organelle, and the flagellar hook is a short, highly curved tubular structure that connects the flagellar motor to the long filament acting as a helical propeller . The hook is made of about 120 copies of a single protein, FlgE, and its function as a nano-sized universal joint is essential for dynamic and efficient bacterial motility and taxis . It transmits the motor torque to the helical propeller over a wide range of its orientation for swimming and tumbling . Here we report a partial atomic model of the hook obtained by X-ray crystallography of FlgE31, a major proteolytic fragment of FlgE lacking unfolded terminal regions, and by electron cryomicroscopy and three-dimensional helical image reconstruction of the hook . The model reveals the intricate molecular interactions and a plausible switching mechanism for the hook to be flexible in bending but rigid against twisting for its universal joint function.

Plant Cell Physiol, 2004 Sep, 45(9), 1299 - 305
Two cytokinin receptors of Arabidopsis thaliana, CRE1/AHK4 and AHK3, differ in their ligand specificity in a bacterial assay; Spichal L et al.; Strains of Escherichia coli that express two different cytokinin receptors of Arabidopsis thaliana, CRE1/AHK4 and AHK3, were used to study the relative sensitivity of these receptors to various cytokinins . Both receptors were most sensitive to the bases of the isoprenoid-type cytokinins trans-zeatin and isopentenyladenine but differed significantly in the recognition of other cytokinin compounds . In particular, CRE1/AHK4 recognized at 1 microm concentration only trans-zeatin while AHK3 recognized cis-zeatin and dihydrozeatin as well, although with a lower sensitivity . Similarly, CRE1/AHK4 was not activated by cytokinin ribosides and ribotides, but AHK3 was . Comparisons using the ARR5::GUS fusion gene as a cytokinin reporter in Arabidopsis showed similar relative degrees of responses in planta, except that cytokinins with aromatic side chains showed much higher activities than in the bacterial assay . These results indicate that the diverse cytokinin compounds might have specific functions in the numerous cytokinin-regulated processes, which may depend in turn on different receptors and their associated signalling pathways . The importance of precise control of local concentrations of defined cytokinin metabolites to regulate the respective downstream event is corroborated.

Sci Prog, 2003, 86(Pt 4), 271 - 82
Bacterial responses to alkaline stress; Saito H et al.; Studies of bacterial adaptation to alkaline pH have been less extensive to date compared with those of acidic pH . Recent development of novel methods for global analysis of gene expression under various conditions revealed that many genes were induced at high pH . These data led us to question why so many genes are required for adaptation to alkaline pH . The internal pH of bacteria growing at extremely high pH remains unclear because the methods for measuring interior acidic deltapH developed to date are not so accurate, but it is generally accepted that cytoplasmic pH increases with medium alkalization, although the increase is lower than that of the change in medium pH . Therefore, activities of enzymes working in neutral cytoplasm may decrease with cytoplasmic alkalization under extreme alkaline conditions . Based on these findings, we propose in this article that genes whose products have an optimum activity at high pH are induced under alkaline stress to compensate for the decrease in activities of systems functioning at neutral pH.

Jpn J Infect Dis, 2004 Oct, 57(5), S19 - 21
Neutrophil microbicidal activity: screening bacterial mutants for survival after phagocytosis using quantitative PCR; Rosen H et al.; When a constant gene replacement sequence is introduced into bacteria to produce mutants and the flanking chromosomal sequences are known, it is possible to use a quantitative polymerase chain reaction method (QPCR) to compare the concurrent survival of the different bacterial mutants under identical conditions . We describe Escherichia coli survival following neutrophil phagocytosis among three mutants deleted respectively for araB, dps or oxyR . Comparisons were made both by traditional and QPCR methods with similar results and indicate that the survival defect of an oxyR and oxyS mutant described previously can be attributed to the loss of oxyR alone . Deletion of dps, a prominent member of the regulon controlled by the oxyR gene product does not engender a survival defect . We suggest that QPCR analysis can readily compare the relative survival of 10 or more mutants concurrently . QPCR analysis would seem to be especially valuable when experimental conditions are subject to a high degree of sample to sample variability or when the stress producing system involves use of expensive or scarce resources like rare patient cells, cells from children, or the use of genetically modified animal hosts.

Vet Immunol Immunopathol, 2004 Dec 8, 102(3), 165 - 78
The combination of PRRS virus and bacterial endotoxin as a model for multifactorial respiratory disease in pigs; Van Gucht S et al.; This paper reviews in vivo studies on the interaction between porcine reproductive and respiratory syndrome virus (PRRSV) and LPS performed in the authors' laboratory . The main aim was to develop a reproducible model to study the pathogenesis of PRRSV-induced multifactorial respiratory disease . The central hypothesis was that respiratory disease results from an overproduction of proinflammatory cytokines in the lungs . In a first series of studies, PRRSV was shown to be a poor inducer of TNF-alpha and IFN-alpha in the lungs, whereas IL-1 and the anti-inflammatory cytokine IL-10 were produced consistently during infection . We then set up a dual inoculation model in which pigs were inoculated intratracheally with PRRSV and 3-14 days later with LPS . PRRSV-infected pigs developed acute respiratory signs for 12-24h upon intratracheal LPS inoculation, in contrast to pigs inoculated with PRRSV or LPS only . Moreover, peak TNF-alpha, IL-1 and IL-6 titers were 10-100 times higher in PRRSV-LPS inoculated pigs than in the singly inoculated pigs and the cytokine overproduction was associated with disease . To further prove the role of proinflammatory cytokines, we studied the effect of pentoxifylline, a known inhibitor of TNF-alpha and IL-1, on PRRSV-LPS induced cytokine production and disease . The clinical effects of two non-steroidal anti-inflammatory drugs (NSAIDs), meloxicam and flunixin meglumine, were also examined . Pentoxifylline, but not the NSAIDs, significantly reduced fever and respiratory signs from 2 to 6h after LPS . The levels of TNF-alpha and IL-1 in the lungs of pentoxifylline-treated pigs were moderately reduced, but were still 26 and 3.5-fold higher than in pigs inoculated with PRRSV or LPS only . This indicates that pathways other than inhibition of cytokine production contributed to the clinical improvement . Finally, we studied a mechanism by which PRRSV may sensitize the lungs for LPS . We hypothesized that PRRSV would increase the amount of LPS receptor complex in the lungs leading to LPS sensitisation . Both CD14 and LPS-binding protein, two components of this complex, increased significantly during infection and the amount of CD14 in particular was correlated with LPS sensitisation . The increase of CD14 was mainly due to infiltration of strongly CD14-positive monocytes in the lungs . The PRRSV-LPS combination proved to be a simple and reproducible experimental model for multifactorial respiratory disease in pigs . To what extent the interaction between PRRSV and LPS contributes to the development of complex respiratory disease is still a matter of debate.

Sex Transm Dis, 2004 Nov, 31(11), 691 - 4
Bacterial vaginosis in lesbians and bisexual women; Bailey JV et al.; OBJECTIVE: To determine whether bacterial vaginosis (BV) is associated with sexual activity between women . STUDY DESIGN: Cross-sectional survey of 708 new patients attending 2 sexual health clinics for lesbians and bisexual women in London, U.K . Questionnaire for demographic, sexual history, and sexual practice data linked with the results of genitourinary examination . RESULTS: BV was common (31.4%) . The odds of BV was significantly associated with larger numbers of female sexual partners (odds ratio {OR}, 1.6; confidence interval {CI}, 1.05-2.44 for > or = 11 compared with 1-5 partners) and with smoking (OR, 1.43; CI, 1.01-2.03), but not with sex with men or vaginal douching . CONCLUSIONS: BV is common in women who have sex with women (WSW) . The increasing odds of BV with larger numbers of female sexual partners suggest that BV may be sexually transmitted between women.

DNA Res, 2004 Aug 31, 11(4), 219 - 31, 311-313
Estimation of the number of authentic orphan genes in bacterial genomes; Fukuchi S et al.; Genome annotation produces a considerable number of putative proteins lacking sequence similarity to known proteins . These are referred to as "orphans." The proportion of orphan genes varies among genomes, and is independent of genome size . In the present study, we show that the proportion of orphan genes roughly correlates with the isolation index of organisms (IIO), an indicator introduced in the present study, which represents the degree of isolation of a given genome as measured by sequence similarity . However, there are outlier genomes with respect to the linear correlation, consisting of those genomes that may contain excess amounts of orphan genes . Comparisons of genome sequences among closely related strains revealed that some of the annotated genes are not conserved, suggesting that they are ORFs occurring by chance . Exclusion of these non-conserved ORFs within closely related genomes improved the correlation between the proportion of orphan genes and the IIO values . Assuming that the correlation holds in general, this relationship was used to estimate the number of "authentic" orphan genes in a genome . Using this definition of authentic orphan genes, the anomalies arising from over-assignments, e.g., the percentages of structural annotations, were corrected for 16 genomes, including those of five archaea.

Acta Paediatr, 2004 Oct, 93(10), 1378 - 85
Prediction of academic and behavioural limitations in school-age survivors of bacterial meningitis; Koomen I et al.; AIM: To develop a prediction rule to identify postmeningitic children at high risk of academic and behavioural limitations . METHODS: 182 children (mean age 10 y; range 5-14) were selected from a cohort of 674 school-age survivors of bacterial meningitis . These children had neither meningitis with "complex onset", nor prior cognitive or behavioural problems, nor severe disease sequelae . On average, 7 y after the meningitis, they were evaluated using an "Academic Achievement Test", and their parents filled in the "Child Behaviour Checklist" . By reviewing the medical records, potential risk factors for academic and/or behavioural limitations were collected . Independent predictors were identified using multivariate logistic regression analysis, leading to the formulation of a prediction rule . RESULTS: The cumulative incidence of academic and/or behavioural limitations among children who survived bacterial meningitis without severe disease sequelae was 32% . The prediction rule was based on nine independent risk factors: gender, birthweight, educational level of the father, S . pneumoniae, cerebrospinal fluid leukocyte count, delay between admission and start of antibiotics, dexamethasone use, seizures treated with anticonvulsive therapy, and prolonged fever . When 10 was taken as a cut-off point for the risk score computed using this rule, 76% of the children with limitations could be identified, while 38% of the children in the cohort were selected as at risk for these limitations . CONCLUSION: With a prediction rule based on nine risk factors, postmeningitic children at high risk of developing academic and/or behavioural limitations could be identified . Additional research is required to further validate this prediction rule . In the future, a careful follow-up of high risk children may enhance early detection and treatment of these limitations.

Carcinogenesis . 2004 Oct 21; {Epub ahead of print}
Anti-tumor promotional effects of a novel intestinal bacterial metabolite (IH-901) derived from the protopanaxadiol type ginsenosides in mouse skin; Lee JY et al.; Epidemiological studies have demonstrated that ginseng intake decreases the risk of cancer . Ginseng saponins (ginsenosides) have been regarded as principal components responsible for the majority of pharmacological activities exerted by ginseng . IH-901 {20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol}, an intestinal bacterial metabolite derived from protopanaxadiol type saponins of Panax ginseng C.A . Meyer, has been reported to possess anti-tumor effects, including inhibition of invasion, metastasis and angiogenesis and induction of tumor cell apoptosis . Tumor promotion often accompanies an elevated ornithine decarboxylase (ODC) activity, acute inflammation, and induction of cyclooxygenase-2 (COX-2) activity . Here we examined the effects of IH-901 on tumor promotion and related molecular events in mouse skin in vivo . IH-901 pretreatment inhibited ear edema induced by the prototype tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in a female ICR mice . Topical application of IH-901 onto shaven backs of female ICR mice led to inhibition of TPA-induced expression of COX-2 and production of prostaglandin E2 . The eukaryotic transcription factor NF-kappaB has been involved in intracellular signaling pathways associated with inflammation and carcinogenesis . IH-901 attenuated TPA-induced epidermal NF-kappaB DNA binding in mouse skin which appeared to be mediated by blocking phosphorylation and subsequent degradation of IkappaBalpha . In an attempt to elucidate the molecular mechanisms by which IH-901 inactivates NF-kappaB, its effects on activation of upstream signaling kinases were explored . IH-901 treatment mitigated the activation of ERK1/2 and Akt signaling . In another experiment, topically applied IH-901 suppressed the activity as well as expression of ODC in a dose-dependent fashion . In addition, IH-901 given prior to each topical dose of TPA markedly lowered the number of papillomas in mouse skin induced by 7,12-dimethylbenz{a}anthracene . Taken together, these findings suggest that IH-901 exerts anti-inflammatory effects by inhibiting TPA-induced COX-2 expression, which may contribute to its anti-tumor promoting effects on mouse skin carcinogenesis.

Mol Plant Microbe Interact, 2004 Oct, 17(10), 1139 - 45
Tobacco genes induced by the bacterial effector protein AvrPto; Thara VK et al.; The type III effector protein AvrPto acts as a virulence factor in susceptible plants lacking a cognate resistance gene but triggers hypersensitive response and disease resistance in tomato plants carrying the Pto gene or in tobacco plants carrying an unknown resistance gene . To assist the characterization of cellular responses caused by AvrPto in the plant, a pathogen-free system was adopted to isolate genes up-regulated 12 h after induced expression of AvrPto . By using subtraction cloning and transgenic tobacco plants expressing avrPto as a transgene, we isolated 125 nonredundant cDNA clones that represent avrPto-response genes (ARG) . In addition to genes that are known to be induced by Pto-avrPto recognition, a number of new genes were also isolated . Most of ARG showed a specific induction in tobacco plants challenged with incompatible or nonhost pathogens . The use of an avrPto mutant that selectively eliminated the avrPto recognition in tobacco demonstrated that the ARG were induced in a highly specific manner by the avirulence, instead of the virulence activity of avrPto.

Urol Res, 2004 Aug, 32(4), 266 - 70
Bacterial translocation in experimental uremia; de Almeida Duarte JB et al.; The aim of this study was to investigate whether or not experimental uremia would induce bacterial translocation . Forty male Wistar rats were randomized into two groups: uremic (n = 20) and control (n = 20) . Under anesthesia, the upper and lower left renal poles and the marginal lateral parenchyma were excised in uremic group . Seven days later, in a second operation, the liver, spleen and the mesenteric lymph nodes (MLN) were excised and cultured . Blood samples were sent for biochemical analysis (BUN, creatinine, sodium and potassium) and cultured . Specimens of the jejunum (1 cm below the Treitz angle) and ileum (1 cm above the ileocecal valve) were collected and sent for histological examination and scored for the degree of inflammation of the mucosa using a classification proposed by Chiu et al . in 1970 . Uremic rats presented higher BUN, creatinine and potassium than controls . Bacterial translocation was more frequent in uremic than in control animals (8/20 (40%) vs . 1/20 (5%); p = 0.02) . Translocation in uremic rats was observed mainly at the MLN (all eight cases) . Both at the jejunum (uremic = 3 {0-5} vs . control = 2 {0-4}; p = 0.04) and the ileum (uremic - 2 {0-5} vs . control = 0 {0-3}; p = 0.01), inflammation score was higher in uremic rats than in controls . The intestinal mucosa barrier is impaired and bacterial translocation occurs in experimental uremia .

J Biochem (Tokyo), 2004 Aug, 136(2), 199 - 209
Interchangeability and distinct properties of bacterial Fe-S cluster assembly systems: functional replacement of the isc and suf operons in Escherichia coli with the nifSU-like operon from Helicobacter pylori; Tokumoto U et al.; The assembly of iron-sulfur (Fe-S) clusters, a key step in the post-translational maturation of Fe-S proteins, is mediated by a complex apparatus . In E . coli, this process involves two independent systems called ISC and SUF encoded by the iscSUA-hscBA-fdx gene cluster and sufABCDSE operon, respectively . Another system, termed NIF (nifSU), is required for the maturation of nitrogenase in nitrogen-fixing bacteria . We have developed a novel genetic system to gain further insight into these multi-component systems, and to determine how ISC, SUF and NIF might differ in their roles in Fe-S assembly . We have constructed an E . coli mutant lacking both the isc and suf operons, and this strain can only survive in the presence of a complementing plasmid . Using the plasmid replacement technique, we examined the isc and suf operons, and identified the genes essential for the function . Additionally, we have found that nifSU-like genes cloned from Helicobacter pylori are functionally exchangeable with the isc and suf operons . Thus, the NIF-like system participates in the maturation of a wide variety of Fe-S proteins . An increased ability of NIF to complement isc and suf loss was seen under anaerobic conditions . This may explain why the NIF system is only found in a limited number of bacterial species, and most other organisms prefer the ISC and/or SUF systems . While the differences between ISC and SUF were small with respect to the complementing activity, the SUF system appears to be more advantageous for bacterial growth in the presence of hydrogen peroxide.

Curr Hematol Rep, 2004 Nov, 3(6), 450 - 5
Bacterial contamination of blood products; Palavecino E et al.; The occurrence of a septic reaction resulting from bacterial contamination of blood products, particularly with room-temperature stored platelets, is the most common transfusion-associated infectious risk in the United States . Bacterial contamination of blood products was first identified more than 60 years ago; yet, strategies to resolve this problem have proved daunting despite ongoing awareness and increasing concern especially in the last few years . With the recent US Food and Drug Administration (FDA) approval of culture methods for quality control testing of platelet units and the promulgation of accreditation standards by the College of American Pathologists and American Association of Blood Banks to detect bacterially contaminated platelet units and to prevent transfusion of these units, blood banks and transfusion services have finally started to address this problem, in a more standardized manner . Furthermore, as new methods of interdicting, inactivating and detecting bacterially contaminated blood products emerge, it is hoped that the problem of bacterial contamination of blood products will be overcome.

Emerg Infect Dis, 2004 Aug, 10(8), 1357 - 62
Genomic-scale analysis of bacterial gene and protein expression in the host; Boyce JD et al.; The developing complementary technologies of DNA microarrays and proteomics are allowing the response of bacterial pathogens to different environments to be probed at the whole genome level . Although using these technologies to analyze pathogens within a host is still in its infancy, initial studies indicate that these technologies will be valuable tools for understanding how the pathogen reacts to the in vivo microenvironment . Some bacterial pathogens have been shown to substantially modify their surface components in response to the host immune system and modify their energy metabolism and transport pathways to allow efficient growth within the host . Further detailed analyses of these responses will increase understanding of the molecular mechanisms of pathogenesis, identify new bacterial virulence factors, and aid in the design of new vaccines.

J Environ Sci (China), 2004, 16(4), 581 - 4
Diversity surveys of soil bacterial community by cultivation--based methods and molecular fingerprinting techniques; Luo HF et al.; By combining the cultivation methods with molecular fingerprinting techniques, the diversity surveys of soil bacterial community in 13 areas of China were carried out . The cultivable heterotrophic diversity was investigated by colony morphology on solid LB medium . Genetic diversity was measured as bands on denaturing gradient gel electrophoresis(DGGE) by the extraction and purification of the total soil DNA, and amplification of bacterial 16S rDNA fragments by polymerase chain reaction (PCR) . The Shannon-Wiener indices of diversity (H), richness (S) and evenness (E(H)) were employed to estimate the diversity of soil bacterial community . The results showed that there was an obvious diversification existed in soil from the different areas . However, the genetic diversity estimated by PCR-DGGE can provide more comprehensive information on bacterial community than the cultivation-based methods . Therefore, it is suggested to combine the traditional methods with genetic fingerprinting techniques to survey and estimate soil bacterial diversity.

Mol Microbiol, 2004 Nov, 54(3), 665 - 75
Intestinal barrier dysfunction by enteropathogenic Escherichia coli is mediated by two effector molecules and a bacterial surface protein; Dean P et al.; The human intestinal pathogen, enteropathogenic Escherichia coli (EPEC), causes diarrhoeal disease by a mechanism that is dependent on the injection of effector proteins into the host cell . One effector, EspF, is reported to be required for EPEC to disrupt tight junction integrity of intestinal cells and increase the paracellular movement of molecules, which is likely to contribute to diarrhoea . Here, we show that not one but three EPEC-encoded factors play important roles in this process . Thus, the Map (Mitochondria-associated protein) effector is shown to: (i) be as essential as EspF for disrupting intestinal barrier function, (ii) be able to function independently of EspF, (iii) alter tight junction structure and (iv) mediate these effects in the absence of mitochondrial targeting . Additionally, the outer membrane protein Intimin is shown to be crucial for EspF and Map to disrupt the intestinal barrier function . This function of Intimin is completely independent of its interaction with its known receptor Tir, revealing a physiologically relevant requirement for Intimin interaction with alternative receptor(s) . This work demonstrates that EPEC uses multiple multifunctional proteins to elicit specific responses in intestinal cells and that EPEC can control the activity of its injected effector molecules from its extracellular location.

Mol Microbiol, 2004 Nov, 54(3), 588 - 97
Bacterial cell division and the septal ring; Weiss DS; Cell division in bacteria is mediated by the septal ring, a collection of about a dozen (known) proteins that localize to the division site, where they direct assembly of the division septum . The foundation of the septal ring is a polymer of the tubulin-like protein FtsZ . Recently, experiments using fluorescence recovery after photobleaching have revealed that the Z ring is extremely dynamic . FtsZ subunits exchange in and out of the ring on a time scale of seconds even while the overall morphology of the ring appears static . These findings, together with in vitro studies of purified FtsZ, suggest that the rate-limiting step in turnover of FtsZ polymers is GTP hydrolysis . Another component of the septal ring, FtsK, is involved in coordinating chromosome segregation with cell division . Recent studies have revealed that FtsK is a DNA translocase that facilitates decatenation of sister chromosomes by TopIV and resolution of chromosome dimers by the XerCD recombinase . Finally, two murein hydrolases, AmiC and EnvC, have been shown to localize to the septal ring of Escherichia coli, where they play an important role in separation of daughter cells.

Clin Exp Obstet Gynecol, 2004, 31(3), 232 - 4
Resuscitation with modified gelatin causes higher bacterial translocation in experimental sublethal hemorrhagic shock; Eroglu E et al.; The effect of colloidal solutions on bacterial translocation was studied . Sublethal hemorrhagic shock was established by blood withdrawal until the mean arterial pressure fell to 40 mmHg within 15 min on 36 adult Wistar Albino rats . Resuscitation was performed using four different solutions with the same amount of blood . Group I (n = 9) 0.9% NaCl, Group II (n = 9) 10% dextran 40, Group III (n = 9) 6% hydroxyethyl starch, Group IV (n = 9) 4% modified fluid gelatin . Before resuscitation and after anesthesia blood samples were drawn to analyze pH, PCO2, PO2, SaO2, HCO3 and ABE values . Twenty-four hours after anesthesia laparotomy was performed to obtain tissue samples of the liver, spleen and mesenteric lymph nodes . Samples were cultured on EMB and blood agar media . Results were analyzed with the one-way ANOVA and Post-hoc test (Tukey's HSD) . The translocated bacteria were mainly Eschericia coli and three grew in Group I, two in Group II, three in Group III and six in Group IV . Although there was a trend in difference in bacterial translocation rates among groups, statistical analyses revealed no difference among groups (p < 0.05) . It can be concluded that resuscitation with modified gelatin causes higher bacterial translocation in an experimental sublethal hemorrhagic shock model.

Theor Appl Genet . 2004 Oct 15; {Epub ahead of print}
Construction of bacterial artificial chromosome libraries and their application in developing PCR-based markers closely linked to a major locus conditioning bruchid resistance in mungbean ( Vigna radiata L . Wilczek); Miyagi M et al.; Bacterial artificial chromosome (BAC) libraries have been widely used in different aspects of genome research . In this paper we report the construction of the first mungbean ( Vigna radiata L . Wilczek) BAC libraries . These BAC clones were obtained from two ligations and represent an estimated 3.5 genome equivalents . This correlated well with the screening of nine random single-copy restriction fragment length polymorphism probes, which detected on average three BACs each . These mungbean clones were successfully used in the development of two PCR-based markers linked closely with a major locus conditioning bruchid ( Callosobruchus chinesis) resistance . These markers will be invaluable in facilitating the introgression of bruchid resistance into breeding programmes as well as the further characterisation of the resistance locus.

Trends Microbiol, 2004 Nov, 12(11), 518 - 25
Recent advances on the development of bacterial poles; Janakiraman A et al.; In rod-shaped bacteria, a surprisingly large number of proteins are localized to the cell poles . Polar positioning of proteins is crucial to many fundamental cellular processes . Formation of the pole occurs at the time of a prior cell division event and involves coordination of the cell division machinery with septal placement of newly-synthesized peptidoglycan . Development of polar peptidoglycan and outer membrane depends on the formation of the cytokinetic FtsZ ring at midcell . By contrast, positioning of at least two polar proteins depends on signals independent of both the assembly of the FtsZ ring and the synthesis of septal and polar peptidoglycan . We propose a model for distinct but interrelated developmental pathways for polar cell envelope synthesis and positional information recognized by polar proteins.

Trends Microbiol, 2004 Nov, 12(11), 473 - 5
Bacterial gene regulation: from transcription attenuation to riboswitches and ribozymes; Brantl S; Since the discovery of transcription attenuation as a mechanism of bacterial gene regulation, a broad variety of attenuation mechanisms have been unveiled and analysed . In 2002, the first convincing experimental evidence for metabolite-mediated attenuation, termed riboswitch, was published . Subsequently, riboswitches have been found to be widespread among bacteria and are also used in some eukaryotes . A surprising new finding has been a riboswitch acting as a metabolite-responsive ribozyme - the first new naturally occurring ribozyme discovered since 1990.

Dis Colon Rectum, 2004 Aug, 47(8), 1386 - 9
Functional assessment of bacterial colonization in patients with ileal pouch-anal anastomosis and Brooke ileostomy; Kelly S et al.; PURPOSE: This study was designed to determine whether patients with an ileal pouch-anal anastomosis have increased gastrointestinal bacterial colonization as assessed functionally compared with patients with Brooke ileostomy and to determine the effect of pouch bacterial colonization on pouch function . METHODS: Gastrointestinal bacterial colonization in 27 patients with an ileal pouch-anal anastomosis and 20 patients with a Brooke ileostomy was assessed using the 14C-glycocholate and glucose-hydrogen breath tests . Bacterial colonization was correlated with pouch function and pouch satisfaction . RESULTS: Patients with ileal pouch-anal anastomosis had increased levels of gastrointestinal bacterial colonization as measured using the 14C-glycocholate method compared with patients with Brooke ileostomy (P = 0.03) . Only three patients had a positive result on the glucose hydrogen breath test, two patients with ileal pouch-anal anastomosis, and one with ileostomy; however, the ileal pouch-anal anastomosis patients did have higher levels on this test . Pouch satisfaction and pouch symptoms of urgency were not correlated with levels of bacterial colonization, whereas there was a nonsignificant trend with continence . CONCLUSIONS: We showed increased levels of gastrointestinal bacterial colonization with ileal pouch-anal anastomosis compared with Brooke ileostomy . The increase in bacteria is not limited to the pouch but also are found in the proximal small bowel . There was no correlation between bacterial colonization and urgency, continence, and pouch satisfaction . Reasons for this are discussed.

Fertil Steril . 2004 Oct;82(4):805.
Bacterial endotoxin in the endometrium and its clinical significance in reproduction; Kamiyama S et al.; Bacterial endotoxin was detected in menstrual effluent from infertile women . Endometrial endotoxin appears to influence reproductive process because the pregnancy rate after IVF-ET was significantly associated with an endotoxin level.

Fertil Steril, 2004 Oct, 82(4), 795 - 6
So what is the role of menstrual bacterial endotoxin?
Weiss G.
Bacterial infections may adversely affect ART . However, the meaning and risks of menstrual endotoxin are not known.

Fertil Steril, 2004 Oct, 82(4), 788 - 92
Impact of detection of bacterial endotoxin in menstrual effluent on the pregnancy rate in in vitro fertilization and embryo transfer; Kamiyama S et al.; OBJECTIVE: To examine whether bacterial endotoxin is detectable in menstrual effluent and to analyze a possible association between endotoxin levels and a pregnancy rate after IVF-ET . DESIGN: Prospective observational study . SETTING: University hospital . PATIENT(S): Thirty-eight infertile women undergoing endotoxin assay and IVF-ET . INTERVENTION(S): Endotoxin was assayed by the limulus amoebocyte lysate test . MAIN OUTCOME MEASURE(S): Levels of bacterial endotoxin and a pregnancy rate . RESULT(S): In 38 samples of menstrual effluent taken from 38 women, bacterial endotoxin was detected with a range of 7.1 to >1,000 pg/mL in 37 samples and was not detected in 1 sample . After IVF-ET, pregnancy occurred in 9 of the 38 women . The mean (+/- SD) endotoxin level in these 9 pregnant women was 71.3 +/- 52.5 pg/mL and was significantly lower compared with >236.2 +/- 333.6 pg/mL in the 29 nonpregnant women . All pregnancies occurred in 28 women with an endotoxin level of </=200 pg/mL, whereas no pregnancies occurred in 10 women with an endotoxin level of >200 pg/mL, producing the significantly higher pregnancy rate in the former group than in the latter . CONCLUSION(S): Bacterial endotoxin was detectable in menstrual effluent from infertile women . The pregnancy rate after IVF-ET was significantly higher in women with an endotoxin level of </=200 pg/mL than in women with an endotoxin level of >200.0 pg/mL.

Yi Chuan Xue Bao, 2004 Aug, 31(8), 836 - 41
{Pyramiding of senescence-inhibition IPT gene and Xa23 for resistance to bacterial blight in rice (Oryza sativa L.)}; He GM et al.; Transgenic lines (GC-1) carrying a senescence-inhibition cheimeric gene, IPT (isopentenyl transferase) gene, CBB23, a isogenic lines carrying Xa23 gene for resistance to bacterial blight, and Hexi15, a commercial cultivar showing high resistance to blast disease, were used as donors to pyramid IPT gene and Xa23 by marker-assisted selection (MAS) . Seventeen BC1F1 plants pyramiding Xa23 gene and IPT genes were obtained from three multi-cross combinations . Then, the plants carrying Xa23 and IPT genes were crossed with parental lines of two-line hybrid rice, such as 9311, E32, Pei' ai 64S and W9834S . The progenies were backcrossed the acceptor parents . A total of 17 plants carrying Xa23 and IPT genes were detected by PCR, disease resistance identification and analysis of CTK contents of in the four combinations of "(9311///Hexi15/CBB23// GC-1) x 9311", "(E32///Hexi15/CBB23//GC-1) x E32", "(Pei'ai 64S///Hexi15/CBB23//GC-1) x Pei' ai 64S" and "(GC-1/CBB23//W9834S/Hexi15) x W9834S" . These plants showed resistance to blast disease by inoculating test using 21 the lines of Pyricularia grisea from Northern China . Six plants of BC2F1 pyramiding Xa23 and IPT genes were further obtained in the combinations of "{(9311///Hexi15/CBB23//GC-1) x 9311} x 9311", "{(E32///Hexi15/CBB23//GC-1) x E32} x E32" . After backcrossed and self-crossed 1 approximately 2nd, the plants pyramiding Xa23 and IPT genes can be used in the program of hybrid rice breeding.

Am Surg, 2004 Sep, 70(9), 797 - 800
Regulation of tumor necrosis factor-alpha production in the isolated rat heart stimulated by bacterial lipopolysaccharide or reactive oxygen; Jennings GR et al.; Reperfusion after cardiopulmonary bypass causes induction of reactive oxygen species (ROS), elevated plasma levels of bacterial lipopolysaccharide (LPS), and production of tumor necrosis factor-alpha (TNF) by the heart . Nuclear factor-kappaB (NF-kappaB) regulates the expression of TNF . Because NF-kappaB is activated by both LPS and ROS, we hypothesized that an inhibitor of NF-kappaB, pyrrolidine dithiocarbamate (PDTC), would block release of TNF from the heart stimulated by these two agents . With Institutional animal care and use committee (IACUC) approval, rat hearts were perfused Langendorf style . LPS was infused and ROS were generated with a hypoxanthine/xanthine oxidase system . PDTC was added to the perfusion buffer . Other hearts were treated with forskolin in order to elevate cyclic AMP . Timed collections of coronary effluent were made for the determination of coronary flow and measurement of TNF . LPS stimulated TNF release to a maximum of 2247 +/- 133 pg/min at 150 minutes . PDTC inhibited LPS-stimulated TNF release . For instance, at 150 minutes, LPS-stimulated TNF release was 449 +/- 49 pg/min with 100 microM PDTC and was 70 +/- 65 pg/mL with 250 microM PDTC (P < 0.05 vs LPS alone) . ROS stimulated TNF release was 1494 +/- 130 pg/min at 150 minutes and was not affected by PDTC . Forskolin almost completely blocked TNF release stimulated by LPS or ROS . These data are consistent with the notion that inhibitors of NF-kappaB block cytokine production stimulated by some agents but not others.

Eur J Biochem, 2004 Oct, 271(20), 3978 - 89
Yeast glycogenin (Glg2p) produced in Escherichia coli is simultaneously glucosylated at two vicinal tyrosine residues but results in a reduced bacterial glycogen accumulation; Albrecht T et al.; Saccharomyces cerevisiae possesses two glycogenin isoforms (designated as Glg1p and Glg2p) that both contain a conserved tyrosine residue, Tyr232 . However, Glg2p possesses an additional tyrosine residue, Tyr230 and therefore two potential autoglucosylation sites . Glucosylation of Glg2p was studied using both matrix-assisted laser desorption ionization and electrospray quadrupole time of flight mass spectrometry . Glg2p, carrying a C-terminal (His6) tag, was produced in Escherichia coli and purified . By tryptic digestion and reversed phase chromatography a peptide (residues 219-246 of the complete Glg2p sequence) was isolated that contained 4-25 glucosyl residues . Following incubation of Glg2p with UDPglucose, more than 36 glucosyl residues were covalently bound to this peptide . Using a combination of cyanogen bromide cleavage of the protein backbone, enzymatic hydrolysis of glycosidic bonds and reversed phase chromatography, mono- and diglucosylated peptides having the sequence PNYGYQSSPAM were generated . MS/MS spectra revealed that glucosyl residues were attached to both Tyr232 and Tyr230 within the same peptide . The formation of the highly glucosylated eukaryotic Glg2p did not favour the bacterial glycogen accumulation . Under various experimental conditions Glg2p-producing cells accumulated approximately 30% less glycogen than a control transformed with a Glg2p lacking plasmid . The size distribution of the glycogen and extractable activities of several glycogen-related enzymes were essentially unchanged . As revealed by high performance anion exchange chromatography, the intracellular maltooligosaccharide pattern of the bacterial cells expressing the functional eukaryotic transgene was significantly altered . Thus, the eukaryotic glycogenin appears to be incompatible with the bacterial initiation of glycogen biosynthesis.

J Appl Toxicol, 2004 Sep-Oct, 24(5), 333 - 42
Detection of bioavailable heavy metals in EILATox-Oregon samples using whole-cell luminescent bacterial sensors in suspension or immobilized onto fibre-optic tips; Hakkila K et al.; At the EILATox-Oregon Workshop, nine luminescent whole-cell bacterial sensors were used for the determination of bioavailable metals in blind samples (17 synthetic and 3 environmental) . A non-inducible luminescent control strain was used to determine sample matrix effects and bacterial toxicity . Whole-cell bacterial sensors capable of determining arsenic, inorganic mercury and its organic derivatives, cadmium, lead or copper were used in suspensions and a bacterial sensor for the detection of inorganic mercury was immobilized onto fibre-optic tips using calcium alginate . Bioavailable amounts of metals were estimated using calibration plots, that were constructed to determine the range of metals giving rise to a linear relationship between luminescence and the amount of metals present in the standard solutions . EILATox-Oregon sample 5, which contained 74 mg l(-1) of Hg, gave a significant response with both formats of the mercury sensor . The bioavailable amounts of mercury according to the measurement of bacterial sensor in suspension and immobilized onto a fibre-optic tip were 76 and 93 mg l(-1), respectively . The bacterial sensor for arsenic and copper showed a response with sample 6 (58 mg l(-1) of As) and sample 8 (400 mg l(-1) of metham sodium), respectively . This study showed that the bacterial sensors in suspension or immobilized onto optical fibres are capable of quantifying bioavailable metals from unknown samples . The measurement protocol of bacterial sensors is simple and possible to perform in the field . Moreover, the samples do not need any pretreatment before analysis . Construction and characterization of the strain for the detection of bioavailable copper are described . Copyright (c) 2004 John Wiley & Sons, Ltd.

J Biol Chem . 2004 Oct 8; {Epub ahead of print}
Cytosolic phospholipase A2-alpha is necessary for platelet activating factor biosynthesis, efficient neutrophil mediated bacterial killing and the innate immune response to pulmonary infection; Rubin BB et al.; The role of a cytosolic phospholipase A(2)-alpha (cPLA(2)-alpha) in neutrophil arachidonic acid release, platelet-activating factor (PAF) biosynthesis, NADPH oxidase activation and bacterial killing in vitro, and the innate immune response to bacterial infection in vivo was examined . CPLA(2)-alpha activity was blocked with the specific cPLA(2)-alpha inhibitor Pyrrolidine-1 (human cells) or by cPLA(2)-alpha gene disruption (mice) . cPLA(2)-alpha inhibition or gene disruption led to complete suppression of neutrophil arachidonate release and PAF biosynthesis, but had no effect on neutrophil NADPH oxidase activation, FcgammaII/III or CD11b surface expression, primary or secondary granule secretion or phagocytosis of E . coli in vitro . In contrast, cPLA(2)-alpha inhibition or gene disruption diminished neutrophil mediated E . coli killing in vitro, which was partially rescued by exogenous arachidonic acid or PAF, but not LTB(4) . Following intra-tracheal inoculation with live E . coli in vivo, pulmonary PAF biosynthesis, inflammatory cell infiltration and clearance of E . coli was attenuated in cPLA(2)-alpha mice in comparison with wild type littermates . These studies identify a novel role for cPLA(2)-alpha in the regulation of neutrophil-mediated bacterial killing and the innate immune response to bacterial infection.

Cytokine, 2004 Nov 7, 28(3), 124 - 36
Genetic background influences natural killer cell activation during bacterial peritonitis in mice, and is interleukin 12 and interleukin 18 independent; Scott MJ et al.; Some mouse strains produce strong pro-inflammatory, T-helper (Th)1 responses (e.g . C57BL/6), or strong anti-inflammatory, Th2 responses (e.g . BALB/c) . The exact mechanisms for development of distinct immune responses to infection are not completely understood, although cytokines such as interleukin (IL)-12, IL-18 and IL-4 are known to play roles . Natural killer T (NKT)/natural killer (NK) cells are important regulators of immune responses in infection and non-infection models, and NKT/NK activation is also regulated by IL-12 and IL-18 in many models . We investigated the role of IL-12/IL-18 in NKT/NK activation in murine bacterial peritonitis, as well as differential NKT and NK cell activation in C57BL/6 and BALB/c mice . No differences in NKT or NK cell activation or intracellular interferon (IFN)-gamma were determined between mice given control, anti-IL-12 or anti-IL-18 antibodies or in NKT/NK cell activation in STAT4-/- mice (deficient in IL-12 signaling) or wild type controls . However, there were significant differences in the activation of NKT and NK cells between C57BL/6 mice and BALB/c mice, with NKT/NK cytokine production following Th1 or Th2 lines dependent on strain . This suggests a role for NKT and NK cell activation in the development of Th1 and Th2 responses during bacterial infection independently of IL-12 or IL-18.

IEEE Trans Nanobioscience, 2004 Sep, 3(3), 208 - 16
Evolvable social agents for bacterial systems modeling; Paton R et al.; We present two approaches to the individual-based modeling (IbM) of bacterial ecologies and evolution using computational tools . The IbM approach is introduced, and its important complementary role to biosystems modeling is discussed . A fine-grained model of bacterial evolution is then presented that is based on networks of interactivity between computational objects representing genes and proteins . This is followed by a coarser grained agent-based model, which is designed to explore the evolvability of adaptive behavioral strategies in artificial bacteria represented by learning classifier systems . The structure and implementation of the two proposed individual-based bacterial models are discussed, and some results from simulation experiments are presented, illustrating their adaptive properties.

J Clin Microbiol, 2004 Oct, 42(10), 4838 - 9
Clinical benefit of recovering dermatophytes from skin swabs sent for bacterial culture; Mabbott G et al.; We incubated Sabouraud dextrose agar plates to recover dermatophytes from skin swabs sent for bacterial culture . Dermatophytes were recovered from 66 (0.3%) of 22,613 cultures . Twenty-one patients received specific antifungal treatment when their dermatophyte was reported . Most clinicians thought recovering and reporting the dermatophyte contributed to patient management.

Biotechniques, 2004 Sep, 37(3), 413 - 7
Detection of bacterial endotoxin in human tissues; Nalepka JL et al.; Detection of bacterial lipopolysaccharide (LPS) in the absence of overt infection is a challenging problem in tissue homogenates and other complex samples . We found that conventional Limulus amebocyte lysate (LAL) assays are not suitable for this purpose due to interference from beta-glucan-like molecules . In contrast, a modified LAL assay that is unaffected by beta-glucan-like molecules was able to detect LPS in infected tissue and in a subset of clinically aseptic tissues . A two-step LAL assay was used to exclude the possibility of false positives due to nonspecific amidases . False positives due to sample color were also excluded, as were false negatives due to assay inhibition . This is the first report to successfully detect LPS in tissue in the absence of overt infection . This approach may be extremely useful in assessing recent hypotheses that subclinical levels of bacteria contribute to a wide range of chronic diseases.

Macromol Biosci, 2004 Mar 15, 4(3), 186 - 98
Comonomer-unit compositions, physical properties and biodegradability of bacterial copolyhydroxyalkanoates; Feng L et al.; The comonomer-unit compositions and their distribution of as-produced bacterial copolyesters, including poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxy-butyrate-co-3-hydroxypropionate), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) are described in this paper . Each copolyester sample can be comonomer-unit compositionally fractionated into several fractions, indicating that the original copolymers are mixtures of copolymers with different comonomer-unit compositions . The effects of comonomer-unit compositional distribution on thermal properties, crystallization, biodegradability and solid-state phase behavior are investigated using comonomer compositionally fractionated copolymers.

Biol Pharm Bull, 2004 Oct, 27(10), 1555 - 60
The inhibitory effect of intestinal bacterial metabolite of ginsenosides on CYP3A activity; Liu Y et al.; The intestinal bacterial metabolites of ginsenosides are responsible for the main pharmacological activities of ginseng . The purpose of this study was to find whether these metabolites influence hepatic metabolic enzymes and to predict the potential for ginseng-prescription drug interactions . Utilizing the probe reaction of CYP3A activity, testosterone 6beta-hydroxylation, the effects of derivatives of 20(S)-protopanaxadiol and 20(S)-protopanaxatriol families on CYP3A activity in rat liver microsomes were assayed . Our results showed that ginsenosides from the 20(S)-protopanaxadiol and 20(S)-protopanaxatriol family including Rb1, Rb2, Rc, Compound-K, Re, and Rg1 had no inhibitory effect, whereas Rg2, 20(S)-panaxatriol and 20(S)-protopanaxatriol exhibited competitive inhibitory activity against CYP3A activity in these microsomes with the inhibition constants (Ki) of 86.4+/-0.8 microM, 1.7+/-0.1 microM, and 3.2+/-0.2 microM, respectively . This finding demonstrates that differences in their chemical structure might influence the effects of ginsenosides on CYP3A activity and that ginseng-derived products might have potential for significant ginseng-drug interactions.

J Biol Chem, 2004 Nov 26, 279(48), 49567 - 70 Epub 2004 Nov 26.
Regioselective nitration of tryptophan by a complex between bacterial nitric-oxide synthase and tryptophanyl-tRNA synthetase; Buddha MR et al.; Bacterial nitric-oxide synthase proteins (NOSs) from certain Streptomyces strains have been shown to participate in biosynthetic nitration of tryptophanyl moieties in vivo (Kers, J . A., Wach, M . J., Krasnoff, S . B., Cameron, K . D., Widom, J., Bukhaid, R . A., Gibson, D . M., and Crane, B . R., and Loria, R . (2004) Nature 429, 79-82) . We report that the complex between Deinococcus radiodurans NOS (deiNOS) and an unusual tryptophanyl-tRNA synthetase (TrpRS II) catalyzes the regioselective nitration of tryptophan (Trp) at the 4-position . Unlike non-enzymatic Trp nitration, and similar reactions catalyzed by globins and peroxidases, deiNOS only produces the otherwise unfavorable 4-nitro-Trp isomer . Although deiNOS alone will catalyze 4-nitro-Trp production, yields are significantly enhanced by TrpRS II and ATP . 4-Nitro-Trp formation exhibits saturation behavior with Trp (but not tyrosine) and is completely inhibited by the addition of the mammalian NOS cofactor (6R)-5,6,7,8-tetrahydro-l-biopterin (H(4)B) . Trp stimulates deiNOS oxidation of substrate l-arginine (Arg) to the same degree as H(4)B . These observations are consistent with a mechanism where Trp or a derivative thereof binds in the NOS pterin site, participates in Arg oxidation, and becomes nitrated at the 4-position.

Appl Environ Microbiol, 2004 Oct, 70(10), 5923 - 8
New method for estimating bacterial cell abundances in natural samples by use of sublimation; Glavin DP et al.; We have developed a new method based on the sublimation of adenine from Escherichia coli to estimate bacterial cell counts in natural samples . To demonstrate this technique, several types of natural samples, including beach sand, seawater, deep-sea sediment, and two soil samples from the Atacama Desert, were heated to a temperature of 500 degrees C for several seconds under reduced pressure . The sublimate was collected on a cold finger, and the amount of adenine released from the samples was then determined by high-performance liquid chromatography with UV absorbance detection . Based on the total amount of adenine recovered from DNA and RNA in these samples, we estimated bacterial cell counts ranging from approximately 10(5) to 10(9) E . coli cell equivalents per gram . For most of these samples, the sublimation-based cell counts were in agreement with total bacterial counts obtained by traditional DAPI (4,6-diamidino-2-phenylindole) staining.

Exp Physiol, 2005 Jan, 90(1), 95 - 101 Epub 2004 Oct 04.
Pregnancy influences the plasma cytokine response to intraperitoneal administration of bacterial endotoxin in rats; Fofie AE et al.; Rats have an attenuated febrile response to intraperitoneal (i.p.) administration of exogenous pyrogen (e.g . bacterial endotoxin) near the term of pregnancy . To investigate possible mechanisms of this unique thermoregulatory response, the present experiments were carried out on 18 non-pregnant and 16 near-term pregnant Sprague-Dawley rats to test the hypothesis that pregnancy alters the balance of pyrogenic cytokines and antipyretic and/or cryogenic (antipyretic/cryogenic) cytokines in response to exogenous pyrogen . To test our hypothesis, we measured plasma levels of interleukin (IL)-1beta, IL-6, interleukin-1 receptor antagonist (IL-1ra) and tumour necrosis factor alpha(TNFalpha) at 2 and 4 h following i.p . administration of 160 mug kg(-1) E . coli lipopolysaccharide (LPS) (i.e . EC(100) dose, or the smallest dose that elicits a maximal febrile response in non-pregnant rats) in non-pregnant as well as pregnant rats at day 20 of gestation (term approximately 21 days) . In non-pregnant rats, E . coli LPS elicited statistically significant increases in plasma concentrations of IL-1beta, IL-6, IL-1ra and TNFalpha as compared to that observed following administration of vehicle . However in pregnant rats, E . coli LPS elicited statistically significant increases in antipyretic/cryogenic cytokines (IL-1ra and TNFalpha) but not in pyrogenic cytokines (IL-1beta and IL-6) . Thus, a differential pyrogenic and antipyretic/cryogenic plasma cytokine response may mediate in part the attenuated febrile response to exogenous pyrogen observed in rats near the term of pregnancy.

J Colloid Interface Sci, 2004 Nov 15, 279(2), 410 - 7
Significance of cell electrokinetic properties determined by soft-particle analysis in bacterial adhesion onto a solid surface; Tsuneda S et al.; The influence of extracellular polymeric substances (EPSs) on bacterial cell electrokinetic properties and on cell adhesion onto glass beads in connection with bacterial cell electrokinetic properties was investigated using 12 heterotrophic bacterial strains . Bacterial cell surface properties such as the softness 1/lambda and charge density ZN were determined by Ohshima's soft-particle analysis using the measured electrophoretic mobility as a function of ionic strength . In 10 of 12 strains, when EPSs covering the cell surface were removed, the softness of the cell decreased, indicating that EPS adsorption enhanced the ease of liquid fluid in the ion-penetrable layer on the cell surface . On the other hand, the negative charge density of the cell surface increased for 9 of 12 strains, suggesting that EPSs covering the cell surface decreased the negative charge density of the cell surface layer . In addition, the characteristics of bacterial cell adhesion onto glass beads were evaluated by the packed-bed method and the data were interpreted to indicate cell adhesiveness . As a result, the efficiency of cell adhesion onto glass beads increased as negative cell surface potential psi0 decreased, whereas there seemed to be no correlation between zeta potential and cell adhesiveness . Cell surface potential psi0, which was derived by taking the bacterial polymer layer with EPSs into consideration, provided a more detailed understanding of the electrokinetic properties of bacterial cells.

Bull Soc Pathol Exot, 2004 Aug, 97(3), 207 - 12
{Bacterial and viral epidemics of zoonotic origin; the role of hunting and cutting up wild animals}; Chastel C et al.; Since the Prehistoric times hunting has been a vital activity for man . However, this may account for the contamination of the hunter, his family and relatives . Infections may occur by direct contact with blood or tissues of infected animal during handling and cutting up preys and when preparing or eating meat, or also when bitten by injured animal . Apes and antelopes hunting in sub-Saharan Africa proves to be particularly important since it has been well established that the recent or previous emergence of some viral zoonosis (Ebola, Aids, T lymphotropic viruses and Monkeypox) resulted from hunting and poaching . Moreover predation among different species of non human primates such as that practised by chimpanzees against monkeys, has led to the construction of recombinant simian Lentiviruses, such as SIV cpz able to infect man and then spread over the entire mankind as it was the case with HIV-1 . SARS is another possible example of the zoonotic risks represented by the sale, handling and cutting up Chinese wild animals such as Himalayan civets for culinary purposes.

Biochemistry, 2004 Oct 12, 43(40), 12913 - 23
Protein/lipid interaction in the bacterial photosynthetic reaction center: phosphatidylcholine and phosphatidylglycerol modify the free energy levels of the quinones; Nagy L et al.; The role of characteristic phospholipids of native membranes, phosphatidylcholine (PC), phosphatidylglycerol (PG), and cardiolipin (CL), was studied in the energetics of the acceptor quinone side in photosynthetic reaction centers of Rhodobacter sphaeroides . The rates of the first, k(AB)(1), and the second, k(AB)(2), electron transfer and that of the charge recombination, k(BP), the free energy levels of Q(A)(-)Q(B) and Q(A)Q(B)(-) states, and the changes of charge compensating protein relaxation were determined in RCs incorporated into artificial lipid bilayer membranes . In RCs embedded in the PC vesicle, k(AB)(1) and k(AB)(2) increased (from 3100 to 4100 s(-1) and from 740 to 3300 s(-1), respectively) and k(BP) decreased (from 0.77 to 0.39 s(-1)) compared to those measured in detergent at pH 7 . In PG, k(AB)(1) and k(BP) decreased (to values of 710 and 0.26 s(-1), respectively), while k(AB)(2) increased to 1506 s(-1) at pH 7 . The free energy between the Q(A)(-)Q(B) and Q(A)Q(B)(-) states decreased in PC and PG (DeltaG degrees (Q)A-(Q)B(-->)(Q)A(Q)B- = -76.9 and -88.5 meV, respectively) compared to that measured in detergent (-61.8 meV) . The changes of the Q(A)/Q(A)(-) redox potential measured by delayed luminescence showed (1) a differential effect of lipids whether RC incorporated in micelles or vesicles, (2) an altered binding interaction between anionic lipids and RC, (3) a direct influence of PC and PG on the free energy levels of the primary and secondary quinones probably through the intraprotein hydrogen-bonding network, and (4) a larger increase of the Q(A)/Q(A)(-) free energy in PG than in PC both in detergent micelles and in single-component vesicles . On the basis of recent structural data, implications of the binding properties of phospholipids to RC and possible interactions between lipids and electron transfer components will be discussed.

Biochemistry, 2004 Oct 12, 43(40), 12905 - 12
Dependence of tyrosine oxidation in highly oxidizing bacterial reaction centers on pH and free-energy difference; Kalman L et al.; The pH and temperature dependences of tyrosine oxidation were measured in reaction centers from mutants of Rhodobacter sphaeroides containing a tyrosine residue near a highly oxidizing bacteriochlorophyll dimer . Under continuous illumination, a rapid increase in the absorption change at 420 nm was observed because of the formation of a charge-separated state involving the oxidized dimer and reduced primary quinone, followed by a slow absorption decrease attributed to tyrosine oxidation . Both the amplitude and rate of the slow absorption change showed a pH dependency, indicating that, at low pH, the rate of tyrosine oxidation is limited by the transfer of the phenolic proton to a nearby base . Below 17 degrees C, the rate of the slow absorption change had a strong exponential dependence on the temperature, indicating a high activation energy . At higher pH and temperature, the overall rate of tyrosyl formation appears to be limited by a proposed conformational change in the reaction center that is also observed in reaction centers that do not undergo tyrosine oxidation . The yield of tyrosyl formation measured using electron paramagnetic resonance spectroscopy decreased significantly at 4 degrees C compared to 20 degrees C and was lower at both temperatures in mutants expected to have a slightly smaller driving force for tyrosyl formation.

Biotechnol Bioeng, 2004 Nov 20, 88(4), 528 - 35
Bacterial P450-catalyzed polyketide hydroxylation on a microfluidic platform; Srinivasan A et al.; The incorporation of a multicomponent, cofactor-dependant P450 into a microfluidic biochip is demonstrated . The PikC hydroxylase Streptomyces venezuelae was incorporated into a PDMS-based microfluidic channel . The enzyme was immobilized to Ni-NTA agarose beads via in situ attachment following the addition of the beads to the microchannel . The enzyme loading was approximately 6 microg per mg of beads resulting in a microchannel loading of 10.7 mg/mL . This high enzyme loading enabled the rapid hydroxylation of the macrolide YC-17 to methymycin and neomethymycin in about equal amounts with a conversion of >90% at a flow rate of 70 nL/min . This high reactivity allowed rapid hydroxylation reactions to be performed with short residence times, which is critical for complex enzymes with limited inherent stability . (c) 2004 Wiley Periodicals, Inc

Sex Transm Infect, 2004 Oct, 80(5), 401 - 5
Vaginal leucocyte counts in women with bacterial vaginosis: relation to vaginal and cervical infections; Geisler WM et al.; OBJECTIVES: To evaluate whether an elevated vaginal leucocyte count in women with bacterial vaginosis (BV) predicts the presence of vaginal or cervical infections, and to assess the relation of vaginal WBC counts to clinical manifestations . METHODS: We retrospectively analysed the relation of vaginal leucocyte counts to vaginal and cervical infections and to clinical manifestations in non-pregnant women diagnosed with BV at an STD clinic visit . RESULTS: Of 296 women with BV studied, the median age was 24 years and 81% were African-American . Elevated vaginal leucocyte counts were associated with objective signs of vaginitis and cervicitis and also predicted candidiasis (OR 7.9, 95% CI 2.2 to 28.9), chlamydia (OR 3.1, 95% CI 1.4 to 6.7), gonorrhoea (OR 2.7, 95% CI 1.3 to 5.4), or trichomoniasis (OR 3.4, 95% CI 1.6 to 7.3) . In general, as a screening test for vaginal or cervical infections, vaginal leucocyte count had moderate sensitivities and specificities, low positive predictive values, and high negative predictive values . CONCLUSIONS: An elevated vaginal leucocyte count in women with BV was a strong predictor of vaginal or cervical infections . Vaginal leucocyte quantification may provide an alternative approach to assessing need for empirical therapy for chlamydia and gonorrhoea, particularly in resource-limited high STD risk settings that provide syndromic management.

Obstet Gynecol, 2004 Oct, 104(4), 756 - 60
Frequency of douching and risk of bacterial vaginosis in African-American women; Zhang J et al.; OBJECTIVE: Frequent vaginal douching has been associated with bacterial vaginosis . We investigated whether infrequent douching is also a risk factor for bacterial vaginosis . METHODS: In this cross-sectional study, we recruited 411 African-American women of reproductive age who were visiting gynecologic or family planning clinics of 2 hospitals in New York City from 1999 to 2001 . Detailed information on demographic characteristics, feminine hygiene practice, contraceptive use, and reproductive and medical history was collected through in-person interview . Pelvic examinations and laboratory tests on vaginal secretions were performed . Bacterial vaginosis was defined as Gram stain score of 7 or greater . RESULTS: The overall prevalence of bacterial vaginosis in this population was 27%, similar to the national average . Water-vinegar solution was the most common douche . Although one half of the subjects reported douching regularly, only 2% douched frequently (once per week or more) . Frequent douching in the past 3 months had a prevalence ratio of bacterial vaginosis of 2.35 (95% confidence interval 0.98-5.63) . However, douching less than once per week was not associated with bacterial vaginosis . CONCLUSION: Douching less than once per week, particularly with a water-vinegar douche, is not associated with bacterial vaginosis in this African-American population . LEVEL OF EVIDENCE: III

Eur J Oral Sci, 2004 Oct, 112(5), 419 - 23
Relationship between bacterial infection and evaluation using a laser fluorescence device, DIAGNOdent; Iwami Y et al.; The aim of this in vitro study was to investigate the relationship between bacterial infections in carious dentin when detected by two different methods -- polymerase chain reaction (PCR), and a laser fluorescence device, DIAGNOdent . Dentin was removed every 300 micro m in the direction of the pulp chamber in 10 extracted molars with occlusal dentin caries and 3 extracted sound molars . Dentin surfaces were evaluated using DIAGNOdent, and dentinal tissue samples were removed by using a round bur before and after each removal . Bacterial DNA in the dentinal tissues was detected by PCR, using primers based on the nucleotide sequence of a conserved region of the 16S rDNA, and yielded a PCR product of 466 bp . The rates of bacterial detection increased as the DIAGNOdent values increased . In the 10 specimens, the lowest DIAGNOdent value at which bacteria were detected was 15.6; at DIAGNOdent values below 15.6, no bacteria were detected . The results of a receiver operating characteristic (ROC) curve for the DIAGNOdent values showed that the area under the ROC curve was 0.91 . This study clarified the relationship between the DIAGNOdent values of dentin caries and the rates of bacterial detection.

Biotechnol Prog, 2004 Sep-Oct, 20(5), 1309 - 24
DNA microarrays: experimental issues, data analysis, and application to bacterial systems; Dharmadi Y et al.; DNA microarrays are currently used to study the transcriptional response of many organisms to genetic and environmental perturbations . Although there is much room for improvement of this technology, its potential has been clearly demonstrated in the past 5 years . The general consensus is that the bottleneck is now located in the processing and analysis of transcriptome data and its use for purposes other than the quantification of changes in gene expression levels . In this article we discuss technological aspects of DNA microarrays, statistical and biological issues pertinent to the design of microarray experiments, and statistical tools for microarray data analysis . A review on applications of DNA microarrays in the study of bacterial systems is presented . Special attention is given to studies in the following areas: (1) bacterial response to environmental changes; (2) gene identification, genome organization, and transcriptional regulation; and (3) genetic and metabolic engineering . Soon, the use of DNA microarray technologies in conjunction with other genome/system-wide analyses (e.g., proteomics, metabolomics, fluxomics, phenomics, etc.) will provide a better assessment of genotype-phenotype relationships in bacteria, which serve as a basis for understanding similar processes in more complex organisms.

ANZ J Surg, 2004 Oct, 74(10), 900 - 4
C-reactive protein may be a marker of bacterial translocation in experimental intestinal obstruction; Cevikel MH et al.; BACKGROUND: C-reactive protein (CRP) is used as a marker of intestinal ischaemia . This study evaluated whether CRP levels can be used to detect ischaemia-induced (strangulated) intestinal obstruction and subsequent bacterial translocation . METHODS: Forty-eight rats, divided into four groups underwent the following procedures: anaesthesia alone (native controls), laparotomy (sham-operated controls), or surgical induction of simple or strangulated intestinal obstruction (simple and strangulated obstruction groups, respectively) . Blood samples were collected for culture and serum CRP analysis . In addition, liver and mesenteric lymph node (MLN) specimens were collected for culture, to determine the presence of bacterial translocation; and ileal segments, for histopathological investigation . RESULTS: CRP levels and rates of bacterial translocation, expressed as colony forming units (cfu) per gram wet tissue, were higher in both intestinal obstruction groups than in the native and sham-operated control groups (P < 0.001 for both) . The increases in CRP levels paralleled increases in the number of cfu in the MLN and liver cultures (P < 0.01) . Compared to controls, animals in the obstruction groups also had a higher incidence of positive blood cultures (P < 0.005) and greater histopathologic evidence of inflammatory infiltration of the lamina propria (P < 0.01) . However, no significant difference between the simple and strangulated obstruction groups was observed . CONCLUSION: CRP levels increase with the severity of bacterial translocation in acute intestinal obstruction but do not permit discrimination between simple and strangulated intestinal obstruction.

Mol Biol (Mosk), 2004 Jul-Aug, 38(4), 578 - 91
{Bacterial and archaeal S-layers as object of bionanotechnology}; Evaluation of the bacterial endotoxin test for quantification of endotoxin contamination of porcine vaccines; National Veterinary Assay Laboratory, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan . ogikubo@nval.go.jp

We investigated the application of the bacterial endotoxin test for the quantification of the endotoxin contamination of various commercial porcine vaccines . In endotoxin-spiked samples, Freund's complete adjuvant and aluminum hydroxide gel adjuvant failed to interfere with the results of the endotoxin test, and both recovery ratios were within the permissible range mentioned in the Japanese Pharmacopoeia . At the various dilutions tested, none of the adjuvants in commercial porcine vaccines caused noteworthy interference in the test . In addition, none of the 39 samples of porcine vaccines approved in Japan induced an interfering effect in the endotoxin test . Our findings suggest that the bacterial endotoxin test using endotoxin-specific Limulus amoebocyte lysate (LAL) can detect endotoxin contamination in commercial porcine vaccines containing either oil or aluminum adjuvants.

Adv Biochem Eng Biotechnol, 2004, 90, 113 - 33
Bacterial sterilization and intracellular protein release by a pulsed electric field; Oshima T et al.; Several biotechnological applications of high-voltage pulsed electric field (PEF) are introduced . Electrical breakdown or disruption of a biological membrane by PEF is understood to occur by electromechanical compression, which results in the formation of transmembrane pores . If the total area of induced pores is small in relation to the total surface area of the membrane, the pores are able to close again mainly through the diffusion of the lipid molecules and rearrangement of the proteins (reversible disruption) . If the total area of the pores becomes unfavorably large, the membrane is no longer able to repair these perturbations (irreversible disruption), and that results in sterilization . We have investigated effective sterilization by using PEF-induced irreversible disruption of biological membranes . The treatment temperature or growth temperature was found to have a great effect on PEF sterilization . The shape of the treatment chamber also proved important for effective PEF sterilization . Therefore, a number of reactors having novel structures were developed . We have also verified that this PEF-induced reversible disruption could be utilized for the selective release of intracellular proteins from yeast and certain gene-engineered Escherichia coli . The secretion of periplasmic protein from E . coli was achieved during cultivation.

J Mol Biol, 2004 Oct 15, 343(2), 291 - 303
An allosteric model for transmembrane signaling in bacterial chemotaxis; Rao CV et al.; Bacteria are able to sense chemical gradients over a wide range of concentrations . However, calculations based on the known number of receptors do not predict such a range unless receptors interact with one another in a cooperative manner . A number of recent experiments support the notion that this remarkable sensitivity in chemotaxis is mediated by localized interactions or crosstalk between neighboring receptors . A number of simple, elegant models have proposed mechanisms for signal integration within receptor clusters . What is a lacking is a model, based on known molecular mechanisms and our accumulated knowledge of chemotaxis, that integrates data from multiple, heterogeneous sources . To address this question, we propose an allosteric mechanism for transmembrane signaling in bacterial chemotaxis based on the "trimer of dimers" model, where three receptor dimers form a stable complex with CheW and CheA . The mechanism is used to integrate a diverse set of experimental data in a consistent framework . The main predictions are: (1) trimers of receptor dimers form the building blocks for the signaling complexes; (2) receptor methylation increases the stability of the active state and retards the inhibition arising from ligand-bound receptors within the signaling complex; (3) trimer of dimer receptor complexes aggregate into clusters through their mutual interactions with CheA and CheW; (4) cooperativity arises from neighboring interaction within these clusters; and (5) cluster size is determined by the concentration of receptors, CheA, and CheW . The model is able to explain a number of seemingly contradictory experiments in a consistent manner and, in the process, explain how bacteria are able to sense chemical gradients over a wide range of concentrations by demonstrating how signals are integrated within the signaling complex.

Curr Opin Microbiol, 2004 Oct, 7(5), 519 - 27
Order and disorder in bacterial genomes; Rocha EP; The availability of sequenced bacterial genomes allows a deeper understanding of their organizational features that are related with fundamental cellular processes such as coordinated gene expression, chromosome replication and cell division . Nevertheless, recent genome comparisons and experimental work highlighted the fluidity of bacterial chromosomes, including genome rearrangements that imperil the selective features of chromosome order . As a result, the clash between elements generating rearrangements and chromosome organization is a classic case of evolutionary conflict.

JPEN J Parenter Enteral Nutr, 2004 Sep-Oct, 28(5), 301 - 7
Effect of enteral nutrition of monoacetoacetin on bacterial translocation in burned rats; Takahata T et al.; BACKGROUND: Bacterial translocation (BT) occurs under stress, and enteral nutrition is said to be effective in counteracting this effect . The usefulness of i.v . nutrition of monoacetoacetine (MA) under stress has been reported previously, and we studied the effect of enteral nutrition of MA as it is related to BT . METHODS: Rats were given 13.6% MA or 15% glucose (Glu) via gastrostomy, and after 4 days a 30% full-thickness burn was made . Before and after administration of the burn, we measured serum cytokines; amounts of bacteria in the mesenteric lymph node (MLN), liver, and spleen (estimation of BT); mucosal thickness of the terminal ileum; and body weight changes . To confirm the effectiveness of MA in the small intestine, we estimated succinyl-CoA:3-oxoacid CoA-transferase (SCOT) expression in the terminal ileum by immunohistochemical staining and Western blot analysis . RESULTS: At 6 hours after burn, all cytokines were lower, and BT in the MLN was inhibited significantly in the MA group . Ileal mucosal thickness was not significantly different, but mucosa was more edematous in the Glu group . At 3 days after burn injury, BT was significantly inhibited in the MLN and liver, and the ileal mucosa was significantly thicker in the MA group . Body weight loss after burn injury was significantly smaller in the MA group . SCOT expression was the strongest at 6 hours after burn injury by Western blot analysis but not by immunohistochemical staining . CONCLUSIONS: Enteral nutrition of MA may be useful for the inhibition of intestinal mucosal atrophy and the prevention of multiple organ dysfunction syndrome caused by the inhibition of BT and subsequent overproduction of cytokines.

Phys Rev E Stat Nonlin Soft Matter Phys . 2004 Aug;70(2 Pt 2):026115 . Epub 2004 Aug 30.
Estimate of blow-up and relaxation time for self-gravitating Brownian particles and bacterial populations; Chavanis PH et al.; We determine an exact asymptotic expression of the blow-up time t(coll) for self-gravitating Brownian particles or bacterial populations (chemotaxis) close to the critical point in d=3 . We show that t(coll) = t(*) (eta- eta(c) )(-1/2) with t(*) =0.917 677 02..., where eta represents the inverse temperature (for Brownian particles) or the mass (for bacterial colonies), and eta(c) is the critical value of eta above which the system blows up . This result is in perfect agreement with the numerical solution of the Smoluchowski-Poisson system . We also determine the exact asymptotic expression of the relaxation time close to but above the critical temperature and derive a large time asymptotic expansion for the density profile exactly at the critical point.

Phys Rev Lett . 2004 Aug 27;93(9):098103 . Epub 2004 Aug 24.
Self-concentration and large-scale coherence in bacterial dynamics; Dombrowski C et al.; Suspensions of aerobic bacteria often develop flows from the interplay of chemotaxis and buoyancy . We find in sessile drops that flows related to those in the Boycott effect of sedimentation carry bioconvective plumes down the slanted meniscus and concentrate cells at the drop edge, while in pendant drops such self-concentration occurs at the bottom . On scales much larger than a cell, concentrated regions in both geometries exhibit transient, reconstituting, high-speed jets straddled by vortex streets . A mechanism for large-scale coherence is proposed based on hydrodynamic interactions between swimming cells.

Chaos, 2004 Sep, 14(3), 562 - 70
Hydrodynamics of bacterial colonies: phase diagrams; Lega J et al.; We present numerical simulations of a recent hydrodynamic model describing the growth of bacterial colonies on agar plates . We show that this model is able to qualitatively reproduce experimentally observed phase diagrams, which relate a colony shape to the initial quantity of nutrients on the plate and the initial wetness of the agar . We also discuss the principal features resulting from the interplay between hydrodynamic motions and colony growth, as described by our model .

Proteins . 2004 Aug 18;57(4):820-828 {Epub ahead of print}
Engineering of a polymeric bacterial protein as a scaffold for the multiple display of peptides; Laplagne DA et al.; Protein assemblies with a high degree of repetitiveness and organization are known to induce strong immune responses . For that reason they have been postulated for the design of subunit vaccines by means of protein engineering . The enzyme lumazine synthase from Brucella spp . (BLS) is highly immunogenic, presumably owing to its homodecameric arrangement and remarkable thermodynamic stability . Structural analysis has shown that it is possible to insert foreign peptides at the ten amino terminus of BLS without disrupting its general folding . These peptides would be displayed to the immune system in a highly symmetric three-dimensional array . In the present work, BLS has been used as a protein carrier of foreign peptides . We have established a modular system to produce chimeric proteins decorated with ten copies of a desired peptide as long as 27 residues and have shown that their folding and stability is similar to that of the wild-type protein . The knowledge about the mechanisms of dissociation and unfolding of BLS allowed the engineering of polyvalent chimeras displaying different predefined peptides on the same molecular scaffold . Moreover, the reassembly of mixtures of chimeras at different steps of the unfolding process was used to control the stoichiometry and spatial arrangement for the simultaneous display of different peptides on BLS . This strategy would be useful for vaccine development and other biomedical applications . Proteins 2004 . (c) 2004 Wiley-Liss, Inc.

EMBO J, 2004 Oct 13, 23(20), 3962 - 72 Epub 2004 Sep 23.
Coordinating assembly and export of complex bacterial proteins; Jack RL et al.; The Escherichia coli twin-arginine protein transport (Tat) system is a molecular machine dedicated to the translocation of fully folded substrate proteins across the energy-transducing inner membrane . Complex cofactor-containing Tat substrates, such as the model (NiFe) hydrogenase-2 and trimethylamine N-oxide reductase (TorA) systems, acquire their redox cofactors prior to export from the cell and require to be correctly assembled before transport can proceed . It is likely, therefore, that cellular mechanisms exist to prevent premature export of immature substrates . Using a combination of genetic and biochemical approaches including gene knockouts, signal peptide swapping, complementation, and site-directed mutagenesis, we highlight here this crucial 'proofreading' or 'quality control' activity in operation during assembly of complex endogenous Tat substrates . Our experiments successfully uncouple the Tat transport and cofactor-insertion activities of the TorA-specific chaperone TorD and demonstrate unequivocally that TorD recognises the TorA twin-arginine signal peptide . It is proposed that some Tat signal peptides operate in tandem with cognate binding chaperones to orchestrate the assembly and transport of complex enzymes.

Acta Paediatr, 2004 Sep, 93(9), 1178 - 84
Expression of neurotrophic factors in cerebrospinal fluid and plasma of children with viral and bacterial meningoencephalitis; Chiaretti A et al.; AIM: To evaluate the expression of neurotrophic factors (nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), glial-derived neurotrophic factor (GDNF)) and their association with the clinical-radiological characteristics and outcome of children with viral and bacterial meningoencephalitis (ME) . METHODS: Prospective observational clinical study performed on 13 children with ME and 12 controls with non-inflammatory obstructive hydrocephalus . Neurotrophic factor levels in the cerebro-spinal fluid (CSF) and plasma were measured using an immunoenzymatic assay . RESULTS: High levels of NGF and BDNF were demonstrated in all patients, while GDNF levels did not undergo significant variations . NGF expression in the CSF was higher in viral ME than in bacterial ME and was correlated with CSF cellularity (particularly mononuclear cells) . BDNF expression in the CSF was higher in bacterial ME than in viral ME and was correlated with CSF cellularity and blood platelet count . No relationships were noted between CSF protein or serum C-reactive protein levels and the expression of neurotrophic factors . Regarding clinical and radiological features, elevated NGF/BDNF levels in the CSF correlated with higher incidence of seizures and prolonged comatose state and with specific radiological lesions . No correlation was found between NGF/BDNF levels and final outcome . CONCLUSIONS: The variations in neurotrophic factor levels may reflect an endogenous attempt at neuroprotection against biochemical and molecular changes during both viral and bacterial ME . The expression of these factors is likely to play a neuro-immunomodulatory or neurosurvival role in ME infections.

Mol Plant Microbe Interact, 2004 Sep, 17(9), 1019 - 28
Proteomic analysis of resistance mediated by Rcm 2.0 and Rcm 5.1, two loci controlling resistance to bacterial canker of tomato; Coaker GL et al.; Two quantitative trait loci from Lycopersicon hirsutum, Rcm 2.0 and Rcm 5.1, control resistance to Clavibacter michiganensis subsp . michiganensis, the causal agent of bacterial canker of tomato . Lines containing Rcm 2.0 and Rcm 5.1 and a susceptible control line were compared at 72 and 144 h postinoculation, using 2-dimensional gel electrophoresis to identify proteins regulated in response to C . michiganensis subsp . michiganensis infection . A total of 47 proteins were subjected to tandem mass spectrometry . Database queries with resulting spectra identified tomato genes for 26 proteins . The remaining 21 proteins were either identified in other species or possessed no homology to known proteins . Spectra were interpreted to deduce peptide amino acid sequences that were then used to query publicly available data . This approach identified tomato genes or expressed sequence tags for 44 of the proteins analyzed . Three superoxide dismutase (SOD) enzymes were differentially regulated among genotypes, and patterns of hydrogen peroxide accumulation were genotype- and tissue-specific, indicating a role for oxidative stress in response to C . michiganensis subsp . michiganensis . Steady-state mRNA and protein levels for SOD, thioredoxin M-type, S-adenosylhomocysteine hydrolase, and pathogenesis-related proteins demonstrated similar patterns of differential regulation . Lines containing Rcm 2.0 and Rcm 5.1 accumulate different proteins and steady-state mRNAs in response to inoculation, suggesting that the two loci may confer resistance through distinct mechanisms.

J Immunol, 2004 Oct 1, 173(7), 4627 - 34
Selective impairment of TLR-mediated innate immunity in human newborns: neonatal blood plasma reduces monocyte TNF-alpha induction by bacterial lipopeptides, lipopolysaccharide, and imiquimod, but preserves the response to R-848; Levy O et al.; Newborns are at increased risk of overwhelming infection, yet the mechanisms underlying this susceptibility are incompletely defined . In this study we report a striking 1- to 3-log decrease in sensitivity of monocytes in human neonatal cord blood, compared with monocytes in adult peripheral blood, to the TNF-alpha-inducing effect of multiple TLR ligands, including bacterial lipopeptides (BLPs), LPS, and the imidazoquinoline compound, imiquimod . In marked contrast, TNF-alpha release in response to R-848, a TLR ligand that is a congener of imiquimod, was equivalent in newborn and adult blood . Differences in ligand-induced TNF-alpha release correlated with divergent ligand-induced changes in monocyte TNF-alpha mRNA levels . Newborn and adult monocytes did not differ in basal mRNA or protein expression of TLRs or mRNA expression of functionally related molecules . Newborn monocytes demonstrated diminished LPS-induced, but equivalent R-848-induced, phosphorylation of p38 mitogen-activated protein kinase and altered BLP- and LPS-induced acute modulation of cognate receptors, suggesting that the mechanism accounting for the observed differences may be localized proximal to ligand recognition by surface TLRs . Remarkably, newborn plasma conferred substantially reduced BLP-, LPS-, and imiquimod-induced TNF-alpha release on adult monocytes without any effect on R-848-induced TNF-alpha release, reflecting differences in a plasma factor(s) distinct from soluble CD14 . Impaired response to multiple TLR ligands may significantly contribute to immature neonatal immunity . Conversely, relative preservation of responses to R-848 may present unique opportunities for augmenting innate and acquired immunity in the human newborn.

J Immunol, 2004 Oct 1, 173(7), 4286 - 96
Divergent trophoblast responses to bacterial products mediated by TLRs; Abrahams VM et al.; Intrauterine infections have been associated with pregnancy complications that are also linked with increased trophoblast apoptosis . TLRs are key components of the innate immune system which recognize conserved sequences on the surface of pathogens and trigger effector cell functions . We hypothesize that intrauterine infections may cause the excessive trophoblast cell apoptosis observed in abnormal pregnancies and that TLR may provide a mechanism of pathogenesis . In this study we describe the expression and function of TLR-2 and TLR-4 in first trimester trophoblast cells . Although ligation of TLR4 induced cytokine production by trophoblast cells, TLR-2 activation induced apoptosis . TLR-2 mediated apoptosis was dependent upon the Fas-associated death domain, the inactivation of the X-linked inhibitor of apoptosis, and the activation of caspases 8, 9, and 3 . These results suggest that certain intrauterine infections may directly induce trophoblast cell death through TLR-2 . Our findings provide a novel mechanism of pathogenesis for certain pregnancy complications in which there is engagement of the innate immune system.

Res Microbiol, 2004 Oct, 155(8), 617 - 22
The unusual transmembrane electron transporter DsbD and its homologues: a bacterial family of disulfide reductases; Porat A et al.; The bacterial membrane protein DsbD transfers electrons across the cytoplasmic membrane to reduce protein disulfide bonds in extracytoplasmic proteins . Its substrates include protein disulfide isomerases and a protein involved in cytochrome {Formula: see text} assembly . Two membrane-embedded cysteines in DsbD alternate between the disulfide-bonded (oxidized) and reduced states in this process.

Proteomics, 2004 Oct, 4(10), 3021 - 33
Proteomic analysis of the sarcosine-insoluble outer membrane fraction of the bacterial pathogen Bartonella henselae; Rhomberg TA et al.; Bartonella henselae is an emerging zoonotic pathogen causing a wide range of disease manifestations in humans . In this study, we report on the analysis of the sarcosine-insoluble outer membrane fraction of B . henselae ATCC 49882 Houston-1 by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (1-D SDS-PAGE) and two-dimensional nonequilibrium pH gradient polyacrylamide gel electrophoresis (2-D NEPHGE) . Protein species were identified by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) and subsequent database query against the B . henselae genome sequence . Subcellular fractionation, application of the ionic detergent lauryl sarcosine, assessment of trypsin sensitivity, and heat modifiability of surface-exposed proteins represented valuable tools for the analysis of the outer membrane subproteome of B . henselae . 2-D NEPHGE was applied to display and catalogue a substantial number of proteins associated with the B . henselae sarcosine-insoluble outer membrane fraction, resulting in the establishment of a first 2-D reference map of this compartment . Thus, 53 distinct protein species associated with the outer membrane subproteome fraction were identified . This study provides novel insights into the membrane biology and the associated putative virulence factors of this pathogen of increasing medical importance.

Eur Arch Otorhinolaryngol . 2004 Sep 18; {Epub ahead of print}
Endoscopy versus radiography for the diagnosis of acute bacterial rhinosinusitis; Berger G et al.; The aim of the study was to estimate the sensitivity and specificity of endoscopy and the diagnostic value of clinical criteria for acute bacterial rhinosinusitis (ABRS) . The hospital records of 117 consecutive patients who had symptoms compatible with ABRS and who underwent sinus radiography and flexible nasendoscopy were retrieved . A positive diagnosis was entertained when radiography demonstrated air fluid level, complete opacification or at least 6 mm mucosal thickening and/or endoscopy revealed purulent material within the drainage area of the sinuses . Using a modified version of the Hui and Walter procedure, the sensitivity and specificity of nasendoscopy was calculated against sinus radiography, a standard reference test, with known estimated sensitivity (76%) and specificity (79%) . The findings show that 40 patients (34%) had positive endoscopy and radiography . Twenty patients (17%) had positive endoscopy and negative radiography, and vice versa in 15 (13%) . In 42 patients (36%) both modalities were negative . Endoscopy yielded a sensitivity of 80% (95% CI, 0.55-1.00) and a specificity of 94% (95% CI, 0.33-1.00) . Although estimates seem better than those of radiography, the confidence intervals are quite wide and no firm conclusion is drawn . Neither single nor combination of symptoms, concurrent with two major and one minor factor advocated by the AAO-HNS Task Force on Rhinosinusitis, were associated with a positive diagnosis of ABRS . The data suggest that endoscopy is no less effective than radiography in predicting ABRS, also that clinical criteria are of rather limited diagnostic value, and thus should be supported by other diagnostic tests . Endoscopy is recommended as a first line diagnostic tool for the diagnosis of ABRS in routine ENT practice . If the outcome is negative, radiography may follow.

J Clin Invest, 2004 Sep, 114(6), 857 - 66
A serine/threonine kinase, Cot/Tpl2, modulates bacterial DNA-induced IL-12 production and Th cell differentiation; Sugimoto K et al.; A serine/threonine protein kinase, Cot/Tpl2, is indispensable for extracellular signal-regulated kinase (ERK) activation and production of TNF-alpha and PGE2 in LPS-stimulated macrophages . We show here that Cot/Tpl2 is also activated by other Toll-like receptor (TLR) ligands . Bacterial DNA rich in the dinucleotide CG (CpG-DNA), unlike LPS or synthetic lipopeptide, activated ERK in a Cot/Tpl2-independent manner . Peritoneal macrophages and bone marrow-derived DCs from Cot/Tpl2-/- mice produced significantly more IL-12 in response to CpG-DNA than those from WT mice . Enhanced IL-12 production in Cot/Tpl2-/- macrophages is, at least partly, regulated at the transcriptional level, and the elevated IL-12 mRNA level in Cot/Tpl2-/- macrophages is accompanied by decreased amounts of IL-12 repressors, such as c-musculoaponeurotic fibrosarcoma (c-Maf) and GATA sequence in the IL-12 promoter-binding protein (GA-12-binding protein; GAP-12) in the nucleus . Consistently, Cot/Tpl2-/- mice showed Th1-skewed antigen-specific immune responses upon OVA immunization and Leishmania major infection in vivo . These results indicate that Cot/Tpl2 is an important negative regulator of Th1-type adaptive immunity, that it achieves this regulation by inhibiting IL-12 production from accessory cells, and that it might be a potential target molecule in CpG-DNA-guided vaccination.

J Biol Chem, 2004 Dec 3, 279(49), 50735 - 42 Epub 2004 Dec 3.
Complex formation between a putative 66-residue thumb domain of bacterial reverse transcriptase RT-Ec86 and the primer recognition RNA; Inouye M et al.; Reverse transcriptases (RT) are found in a minor population of Escherichia coli and are responsible for the synthesis of multicopy single-stranded DNA . These RTs specifically recognize RNA structures in their individual primer-template RNAs to initiate cDNA synthesis from the 2'-OH group of a specific internal G residue (branching G residue) . Here, we purified the 66-residue, C-terminal fragment of RT-Ec86, RT from E . coli, which is responsible for the synthesis of multicopy single-stranded DNA-Ec86 . This fragment, RT-Ec86-(255-320), was found to consist mainly of alpha-helical structures on the basis of its CD spectrum, which is consistent with the prediction of this region as the thumb domain from the structural alignment of RT-Ec86 with human immunodeficiency virus-1 RT . RT-Ec86-(255-320) was able to bind to a 28-base synthetic RNA consisting of the 5'-end single-stranded RNA containing the branching G residue and the recognition stem-loop structure in the RT-Ec86 primer-template RNA with a Kd value of 5 x 10(-8) M . By stepwise shortening of the 5'-end single-stranded region of the RNA, RT-Ec86-(255-320) was found still to be able to form a stable complex with only the stem-loop structure consisting of an 8-bp stem and a 3-base loop . In this stem-loop structure, the UUU loop was essential for the complex formation . RT-Ec73-(251-316) from another E . coli RT could not bind to the 28-base RNA for RT-Ec86 but could bind to its own stem-loop structure having a 3-base AGU loop . These results support the notion that the highly diverse C-terminal regions of bacterial RTs play an important role in recognizing their own specific primer-template RNA structure for the cDNA priming reaction.

Mol Membr Biol, 2004 Jul-Aug, 21(4), 237 - 46
Electroinsertion and activation of the C-terminal domain of colicin A, a voltage gated bacterial toxin, into mammalian cell membranes; Raffy S et al.; The C-terminal fragment of colicin, a protein that is highly soluble in aqueous solution, is spontaneously and irreversibly inserted into the membranes of mammalian cells, which are locally permeabilized by a transmembrane voltage increase . Insertion is detected by immunodetection . This is obtained by mixing the protein with electropermeabilized cells . The same result is observed by pulsing the colicin/cell mixture . Electroinsertion is therefore obtained for the first time with a multi-fragment spanning protein . The cell viability is not affected beyond the effect of electropermeabilization . A train of low voltage repetitive transmembrane modulation, which cannot trigger membrane permeabilization, is applied a day after the electroinsertion . This induces no effect on unmodified cells but triggers the lysis of cells in which colicin has been inserted by the first electropulsation . The low-level electrical treatment is high enough to trigger the voltage gated opening of colicin and to induce the associated toxicity . A transmembrane configuration of colicin is therefore obtained by electroinsertion . The toxic effect of their voltage gating is only obtained when a critical number of voltage gated channels are activated.

Hepatology, 2004 Aug, 40(2), 414 - 23
Kupffer cell-derived interleukin 10 is responsible for impaired bacterial clearance in bile duct-ligated mice; Abe T et al.; Extrahepatic cholestasis often evokes liver injury with hepatocyte apoptosis, aberrant cytokine production, and-most importantly-postoperative septic complications . To clarify the involvement of aberrant cytokine production and hepatocyte apoptosis in impaired resistance to bacterial infection in obstructive cholestasis, C57BL/6 mice or Fas-mutated lpr mice were inoculated intraperitoneally with 10(7) colony-forming units of Escherichia coli 5 days after bile duct ligation (BDL) or sham celiotomy . Cytokine levels in sera, liver, and immune cells were assessed via enzyme-linked immunosorbent assay or real-time reverse-transcriptase polymerase chain reaction . BDL mice showed delayed clearance of E . coli in peritoneal cavity, liver, and spleen . Significantly higher levels of serum interleukin (IL) 10 with lower levels of IL-12p40 were observed in BDL mice following E . coli infection . Interferon gamma production from liver lymphocytes in BDL mice was not increased after E . coli infection either at the transcriptional or protein level . Kupffer cells from BDL mice produced low levels of IL-12p40 and high levels of IL-10 in vitro in response to lipopolysaccharide derived from E . coli . In vivo administration of anti-IL-10 monoclonal antibody ameliorated the course of E . coli infection in BDL mice . Furthermore, BDL-lpr mice did not exhibit impairment in E . coli killing in association with little hepatic injury and a small amount of IL-10 production . In conclusion, increased IL-10 and reciprocally suppressed IL-12 production by Kupffer cells are responsible for deteriorated resistance to bacterial infection in BDL mice . Fas-mediated hepatocyte apoptosis in cholestasis may be involved in the predominant IL-10 production by Kupffer cells .

Quintessence Int, 2004 Sep, 35(8), 630 - 4
Reduction of bacterial levels in dental unit waterlines; Porteous NB et al.; OBJECTIVES: To test the efficacy of an intermittent use, dental unit waterline cleaner, containing 0.12% chlorhexidine, in a proprietary formulation, to reduce bacterial levels in three functioning dental units with independent water reservoir systems . METHOD AND MATERIALS: Baseline water samples were first taken from six units . Two ounces of the undiluted test product was run through lines, left overnight, and flushed out the next morning . This was repeated for 6 nights initially, and once a week thereafter for 12 weeks . Three control dental units did not have chemicals added . Weekly samples were collected in bottles containing sodium thiosulphate on the afternoon before overnight treatment, plated on R2A agar, and incubated at room temperature for 7 days . RESULTS: Mean colony-forming units per millimeter (CFU/mL) in treatment units declined from 23,389 (+/- 20,085) at baseline, to 6 (+/- 10) in week 4, to 5 (+/- 2) in week 12 . Statistical analysis showed a significant difference between treatment and control units . CONCLUSION: Intermittent treatment of dental unit waterlines with 0.12% chlorhexidine gluconate (CHX), in a proprietary formulation, resulted in significantly reduced bacterial counts to levels that were consistently below the American Dental Association's goal of 200 CFU/mL for 8 weeks.

Monaldi Arch Chest Dis, 2004 Jan-Mar, 61(1), 19 - 27
Efficacy of Lantigen B in the prevention of bacterial respiratory infections; Pozzi E et al.; BACKGROUND: Respiratory tract infections are among the most common diseases both in adults and children . METHODS: This multicentre study, was carried out in 212 patients (118 adults with chronic respiratory diseases and 94 children with recurrent respiratory infections) at six Italian study centres . It was performed to establish the efficacy of Lantigen B for the prevention of bacterial complications and/or reduction of associated symptoms . Lantigen B is an oral product based on bacterial lysates of six different inactivated strains commonly involved in respiratory tract infections . RESULTS: The results of prophylactic treatment with Lantigen B in the population investigated were as follows: - the mean incidence of recurrence in the pediatric patients over the 6-month observation period of the study was 1.643 in the placebo group and 1.211 in the Lantigen B group (a relative reduction of 35.7%); - the mean incidence of recurrence in the adult patients over the 6-month observation period of the study was 0.73 in the placebo group and 0.56 in the Lantigen B group (a relative reduction of 30.4%) . The improvement in other important parameters, such as the number of days with a high temperature, cough, and catarrh in the children and objective clinical findings at the lymph nodes of the neck, chest, and pharyngotonsillar region in the adults, provides further evidence of the efficacy of Lantigen B . CONCLUSIONS: This study demonstrates Lantigen B's effectiveness in the prevention of bacterial complications and suggests that it can be used in patients who are particularly at risk of infection (children, the elderly, diabetics, and immunocompromised patients) or those in whom an infection might aggravate a clinical picture that is already inherently complicated (diabetics again, but also patients with heart, kidney, or liver disease).

J Clin Oncol, 2004 Sep 15, 22(18), 3784 - 9
Early hospital discharge followed by outpatient management versus continued hospitalization of children with cancer, fever, and neutropenia at low risk for invasive bacterial infection; Santolaya ME et al.; PURPOSE: To compare outcome and cost of ambulatory versus hospitalized management among febrile neutropenic children at low risk for invasive bacterial infection (IBI) . PATIENTS AND METHODS: Children presenting with febrile neutropenia at six hospitals in Santiago, Chile, were categorized as high or low risk for IBI . Low-risk children were randomly assigned after 24 to 36 hours of hospitalization to receive ambulatory or hospitalized treatment and monitored until episode resolution . Outcome and cost were determined for each episode and compared between both groups using predefined definitions and questionnaires . RESULTS: A total of 161 (41%) of 390 febrile neutropenic episodes evaluated from June 2000 to February 2003 were classified as low risk, of which 149 were randomly assigned to ambulatory (n = 78) or hospital-based (n = 71) treatment . In both groups, mean age (ambulatory management, 55 months; hospital-based management, 66 months), sex, and type of cancer were similar . Outcome was favorable in 74 (95%) of 78 ambulatory-treated children and 67 (94%) of 71 hospital-treated children (P = NS) . Mean cost of an episode was US 638 dollars (95% CI, 572 dollars to 703 dollars) and US 903 dollars (95% CI, 781 dollars to 1,025 dollars) for the ambulatory and hospital-based groups, respectively (P =.003) . CONCLUSION: For children with febrile neutropenia at low risk for IBI, ambulatory management is safe and significantly cost saving compared with standard hospitalized therapy.

Vaccine, 2004 Sep 28, 22(29-30), 4069 - 74
Cloning of the varicella-zoster virus genome as an infectious bacterial artificial chromosome in Escherichia coli; Nagaike K et al.; The complete genome of the varicella-zoster virus (VZV) Oka strain has been cloned as a bacterial artificial chromosome (BAC) . Following electroporation into Escherichia coli (E . coli) strain DH10B, the VZV BAC was stably propagated over multiple generations of its host . Human embryonic lung (HEL) cells transfected with VZV BAC DNA recovered from DH10B showed cytopathic effect (CPE), and virus spread to neighbouring cells was observed . BAC vector sequences are flanked by loxP sites and, coinfection of the reconstituted virus, with a recombinant adenovirus expressing Cre recombinase removed the bacterial sequences . The resulting recombinant rV02 grew as well as the parental virus in HEL cells . The recombinant VZV will promote VZV research and increase use of the viral genome as an investigative tool.

Int J Antimicrob Agents, 2004 Sep, 24 Suppl 1, S49 - 52
NIDDK-sponsored chronic prostatitis collaborative research network (CPCRN) 5-year data and treatment guidelines for bacterial prostatitis; Schaeffer AJ; Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a disabling condition that is poorly understood . The National Institutes of Diabetes and Digestive and Kidney Diseases-sponsored Collaborative Research Network has developed a symptom index, formed a cohort study, a case control study, a full-scale randomised clinical trial, a resource utilisation study and clinical trials, as well as basic research studies, in an effort to better understand and manage patients with this condition . Cohort, case control and resource utilisation studies have confirmed the substantial impact of CP/CPPS . Clinical trials in basic research suggest that anti-inflammatory therapy and alpha-blocker therapy may be effective . The minority of patients with acute or chronic bacterial prostatitis continues to respond favourably to oral fluoroquinolone therapy.

Brain Res, 2004 Oct 8, 1023(1), 48 - 53
Bacterial endotoxin induces STAT3 activation in the mouse brain; Hosoi T et al.; In the present study, we investigated regulatory mechanisms of bacterial endotoxin-induced STAT3 activation in the brain . Intraperitoneal injection of lipopolysaccharide (LPS) dose-dependently (0.5-5000 microg/kg) induced STAT3 phosphorylation in the hypothalamus . LPS-induced STAT3 phosphorylation was peaked at 2-4 h and declined there after . Moreover, intracerebroventricular injection of LPS induced STAT3 phosphorylation in the cortex and the hippocampus, indicating that central as well as peripheral LPS can act in the brain to induce STAT3 activation . Glucocorticoids are known to play a physiological role in the feedback inhibition of immune/inflammatory responses in the endocrine system . Interestingly, we observed no effect of dexamethasone on LPS-induced STAT3 phosphorylation in the hypothalamus . These findings point to the important role of STAT3 in the neuroimmune interaction of inflammation in the brain.

Public Health Nurs, 2004 Sep-Oct, 21(5), 395 - 403
Maternal bacterial vaginosis and fetal/infant mortality in eight Florida counties, 1999 to 2000; Cottrell BH et al.; This study determined the prevalence of maternal bacterial vaginosis (BV) in fetal/infant mortality cases and factors associated with BV . A retrospective descriptive study was utilized . Data were obtained from review of vital statistics and medical records of 176 women experiencing fetal/infant deaths in eight Florida counties, 1999 to 2000 . Non-White mothers accounted for 68.96% of deaths (chi square = 10.119, df = 4, p = 0.038), although the population of the eight counties was 64% White . Of 121 non-White mothers (68.8%) with infections, 37 (30.6%) had BV . Most fetal/infant deaths (39.7%) occurred 20-23 weeks' gestation and at birthweights <500 g, as did most cases of BV (46%) . Women with BV were more likely to be non-White (OR 2.756, 95% CI 1.075, 7.066), single (OR 2.090, 95% CI 1.081, 7.246), <24 years old (t = 3.172, p = 0.002), and have <12 years of education (t = 2.56, p = 0.011) . Findings support early screening and treatment for BV in women with these risk factors or a history of prior fetal/infant loss or preterm/low-birthweight infant . Factors contributing to racial disparity in BV and fetal/infant mortality need further exploration.

J Zhejiang Univ Sci, 2004 Oct, 5(10), 1199 - 205
Production of bacterial blight resistant lines from somatic hybridization between Oryza sativa L . and Oryza meyeriana L; Yan CQ et al.; Novel bacterial blight (BB) resistance gene(s) for rice was (were) introduced into a cultivated japonica rice variety Oryza sativa (cv . 8411), via somatic hybridization using the wild rice Oryza meyeriana as the donor of the resistance gene(s) . Twenty-nine progenies of somatically hybridized plants were obtained . Seven somatically hybridized plants and their parents were used for AFLP (amplified fragment length polymorphism) analysis using 8 primer pairs . Results confirmed that these plants were somatic hybrids containing the characteristic bands of both parents . The morphology of the regenerated rice showed characters of both O . sativa and O . meyeriana . Two somatic hybrids showed highest BB resistance and the other 8 plants showed moderate resistance . The new germplasms with highest resistance have been used in the rice breeding program for the improvement of bacterial blight resistance.

J Mol Recognit, 2004 Sep-Oct, 17(5), 481 - 7
Genomic channeling in bacterial cell division; Mingorance J et al.; The bacterial dcw cluster is a group of genes involved in cell division and peptidoglycan synthesis . Comparison of the cluster across several bacterial genomes shows that its gene content and its gene order are conserved in distant bacterial lineages and, moreover, that, being most conserved in rod-shaped bacteria, the degree of conservation relates to bacterial morphology . We propose a model in which the selective pressure to maintain the cluster arises from the need to efficiently coordinate the processes of elongation and septation in rod-shaped bacteria . Gene order in the dcw cluster would be conserved as a result of mechanisms comprising: (i) a limited amount of peptidoglycan precursors required both for septation and elongation of the wall; (ii) co-translational assembly of the protein complexes involved in cell division and in the synthesis of the peptidoglycan precursors; and (iii) alternation in the cellular localization of the assembled complexes to participate either in the synthesis of the septal peptidoglycan and division, or in the synthesis of the lateral wall . The name genomic channeling is proposed for this model as it involves a genomic arrangement that could facilitate the assembly of specific protein complexes and their subsequent conveyance to specific locations in the crowded cytoplasm and the envelope.

Biomacromolecules, 2004 Sep-Oct, 5(5), 1671 - 7
Effect of sulfate groups from sulfuric acid hydrolysis on the thermal degradation behavior of bacterial cellulose; Roman M et al.; When used as fillers in polymer composites, the thermostability of cellulose crystals is important . Sulfate groups, introduced during hydrolysis with sulfuric acid, are suspected to diminish the thermostability . To elucidate the relationship between the hydrolysis conditions, the number of sulfate groups introduced, and the thermal degradation behavior of cellulose crystals, bacterial cellulose was hydrolyzed with sulfuric acid under different hydrolysis conditions . The number of sulfate groups in the crystals was determined by potentiometric titration . The thermal degradation behavior was investigated by thermogravimetric analysis . The sulfate group content increased with acid concentration, acid-to-cellulose ratio, and hydrolysis time . Even at low levels, the sulfate groups caused a significant decrease in degradation temperatures and an increase in char fraction confirming that the sulfate groups act as flame retardants . Profile analysis of the derivative thermogravimetric curves indicated thermal separation of the degradation reactions by the sulfate groups into low- and high-temperature processes . The Broido method was used to determine activation energies for the degradation processes . The activation energies were lower at larger amounts of sulfate groups suggesting a catalytic effect on the degradation reactions . For high thermostability in the crystals, low acid concentrations, small acid-to-cellulose ratios, and short hydrolysis times should be used.

EMBO J, 2004 Sep 29, 23(19), 3897 - 906 Epub 2004 Sep 09.
Requirement of IS911 replication before integration defines a new bacterial transposition pathway; Duval-Valentin G et al.; Movement of transposable elements is often accompanied by replication to ensure their proliferation . Replication is associated with both major classes of transposition mechanisms: cut-and-paste and cointegrate formation (paste-and-copy) . Cut-and-paste transposition is often activated by replication of the transposon, while in cointegrate formation replication completes integration . We describe a novel transposition mechanism used by insertion sequence IS911, which we call copy-and-paste . IS911 transposes using a circular intermediate (circle), which then integrates into a target . We demonstrate that this is derived from a branched intermediate (figure-eight) in which both ends are joined by a single-strand bridge after a first-strand transfer . In vivo labelling experiments show that the process of circle formation is replicative . The results indicate that the replication pathway not only produces circles from figure-eight but also regenerates the transposon donor plasmid . To confirm the replicative mechanism, we have also used the Escherichia coli terminators (terC) which, when bound by the Tus protein, inhibit replication forks in a polarised manner . Finally, we demonstrate that the primase DnaG is essential, implicating a host-specific replication pathway.

Clin Diagn Lab Immunol, 2004 Sep, 11(5), 936 - 41
Leukotriene B4 receptor (BLT-1) modulates neutrophil influx into the peritoneum but not the lung and liver during surgically induced bacterial peritonitis in mice; Scott MJ et al.; Leukotriene B4 (LTB4) is a rapidly synthesized, early neutrophil chemoattractant that signals via its cell surface receptor, BLT-1, to attract and activate neutrophils during peritonitis . BLT-1-deficient (BLT-1(-/-)) mice were used to determine the effects of LTB4 on neutrophil migration and activation, bacterial levels, and survival after cecal ligation and puncture (CLP) . Male BLT-1(-/-) or wild-type (WT) BALB/c mice underwent CLP . Tissues were harvested for determination of levels of bacteria, myeloperoxidase (MPO), LTB4, macrophage inflammatory protein 2 (MIP-2), and neutrophil (polymorphonuclear leukocyte {PMN}) numbers at 4 and 18 h after CLP . PMN activation was determined by an assessment of phagocytosis ability and CD11b expression . Survival was also determined . BLT-1(-/-) mice had decreased numbers of PMNs in the peritoneum at both 4 and 18 h after CLP but increased numbers of PMNs in the blood at 18 h compared with WT mice . Liver and lung MPO levels were significantly higher in BLT-1(-/-) mice at both 4 and 18 h after CLP, with increased bacterial levels in the blood, the liver, and peritoneal fluid at 4 h . Bacterial levels remained higher in peritoneal fluid at 18 h, but blood and liver bacterial levels at 18 h were not different from levels at 4 h . PMN phagocytosis and CD11b levels were decreased in BLT-1(-/-) mice . LTB4 levels were similar between the groups before and after CLP, but MIP-2 levels were decreased both locally and systemically in BLT-1(-/-) mice . Survival was significantly improved in BLT-1(-/-) mice (71%) compared with WT mice (14%) at 48 h post-CLP . Thus, LTB4 modulates neutrophil migration into the mouse peritoneum, but not the lung or liver, after CLP . Despite higher bacterial and PMN levels at remote sites, there was increased survival in BLT-1(-/-) mice compared to WT mice . Decreased PMN activation may result in less remote organ dysfunction and improved survival.

Bioorg Med Chem Lett, 2004 Sep 6, 14(17), 4519 - 23
Syntheses and anti-MRSA activities of the C3 analogs of mansonone F, a potent anti-bacterial sesquiterpenoid: insights into its structural requirements for anti-MRSA activity; Shin DY et al.; Syntheses and excellent anti-MRSA activities of the mansonone F analogs are reported . In addition, the minimal structural requirements for its anti-MRSA activities as well as its structure-activity relationship including the C3 substituents effects on anti-MRSA activity are also described . In particular, this study revealed that both ortho-quinone and tricyclic systems of mansonone F are essential for anti-MRSA activities.

Am J Ther, 2004 Sep-Oct, 11(5), 412 - 5
Daily needle aspiration versus surgical lavage for the treatment of bacterial septic arthritis in adults; Manadan AM et al.; Septic arthritis is a substantial public health problem, accounting for 0.2-0.7% of hospital admissions . However, despite the availability of effective antibiotics, the appropriate approach to adjunctive therapy remains controversial . Although early drainage is essential to minimize the risks of permanent loss of articular function, it is unclear whether the optimal approach involves arthroscopic lavage or daily arthrocentesis; surgeons appear to prefer surgical lavage because their training routinely considers septic arthritis to be a closed-space infection comparable to an abscess, whereas rheumatologists appear to prefer daily arthrocentesis because of its ease and non-invasive nature . There is a paucity of prospective data comparing the two approaches, and the literature is largely retrospective . Herein, we review the available literature concerning drainage of bacterially infected joints, and conclude that in the absence of prospective randomized clinical trials, the best evidence suggests that there is no compelling reason to recommend surgical lavage for the initial management of uncomplicated septic arthritis.

Microbiol Mol Biol Rev, 2004 Sep, 68(3), 518 - 37, table of contents
Determination of the core of a minimal bacterial gene set; Gil R et al.; The availability of a large number of complete genome sequences raises the question of how many genes are essential for cellular life . Trying to reconstruct the core of the protein-coding gene set for a hypothetical minimal bacterial cell, we have performed a computational comparative analysis of eight bacterial genomes . Six of the analyzed genomes are very small due to a dramatic genome size reduction process, while the other two, corresponding to free-living relatives, are larger . The available data from several systematic experimental approaches to define all the essential genes in some completely sequenced bacterial genomes were also considered, and a reconstruction of a minimal metabolic machinery necessary to sustain life was carried out . The proposed minimal genome contains 206 protein-coding genes with all the genetic information necessary for self-maintenance and reproduction in the presence of a full complement of essential nutrients and in the absence of environmental stress . The main features of such a minimal gene set, as well as the metabolic functions that must be present in the hypothetical minimal cell, are discussed.

Circulation, 2004 Sep 21, 110(12), 1678 - 85 Epub 2004 Sep 07.
Interleukin-1 receptor signaling mediates atherosclerosis associated with bacterial exposure and/or a high-fat diet in a murine apolipoprotein E heterozygote model: pharmacotherapeutic implications; Chi H et al.; BACKGROUND: Current data demonstrate that progressive atherosclerosis is associated with activation of the inflammatory process, as evidenced by systemic elevations of molecules such as tumor necrosis factor, interleukin (IL)-6, and IL-1 . It has been postulated that inflammatory events within an atherogenic lesion are induced by oxidized LDL . Recent evidence suggests that infectious agents, including those that cause periodontal disease, may also play an important role . Studies presented here tested the hypothesis that IL-1 receptor (IL-1R1) signaling plays a crucial role in bacteria- and/or high-fat diet (HFD)-enhanced atherogenesis . METHODS AND RESULTS: Ten-week-old ApoE+/- mice lacking either 1 IL-1R1 allele (ApoE+/-/IL-1R1+/-) or 2 IL-1R1 alleles (ApoE+/-/IL-1R1-/-) fed either an HFD or regular chow were inoculated intravenously with live Porphyromonas gingivalis (P gingivalis) (10(7) CFU), an important periodontal pathogen, or vehicle once per week for 14 or 24 consecutive weeks . Histomorphometry of plaque cross-sectional area in the proximal aortas, en face measurement of plaque area over the aortic trees, and ELISA for systemic proinflammatory mediators were performed . Atherosclerotic lesions of proximal aortas and aortic tree were substantially reduced in ApoE+/-/IL-1R1-/- mice than in ApoE+/-/IL-1R1+/- mice challenged with P gingivalis . At 24 weeks after P gingivalis inoculation, proximal aortic lesion size quantified by histomorphometry was 5-fold-reduced in chow-fed ApoE+/-/IL-1R1-/- mice than in ApoE+/-/IL-1R1+/- mice (P<0.05) . In the HFD group, ApoE+/-/IL-1R1-/- mice exhibited marked attenuation of the progression of atherosclerotic lesions (78% to 97%), with and without P gingivalis inoculation (P<0.05) . CONCLUSIONS: Ablation of IL-1R1 under P gingivalis challenge and/or an HFD reduced the progression of atherosclerotic plaques . These results indicate that IL-1 plays a crucial role in bacteria- and/or HFD-enhanced atherogenesis.

J Altern Complement Med, 2004 Aug, 10(4), 684 - 6
Washing hands before and after performing massages? Changes in bacterial survival count on skin of a massage therapist and a client during massage therapy; Donoyama N et al.; OBJECTIVE: Massage therapy involves direct contact between the therapist and the client in a clinical setting, which can result in the transfer of bacteria . The purpose of this study was to determine the degree of bacteria transfer between a therapist and a client during a massage session and differences between types of lubricants used . DESIGN: Medium cultures were taken from the therapist's palms and the client's skin before, during, and after the massage session . Experiments proceeded with the following settings: use of three different types of lubricants, without the use of a lubricant, and without massage as control . After each massage session, the therapist washed his or her hands and a bacterial sample was again taken . MAIN OUTCOME MEASURES: Changes in bacteria count . RESULTS: (1) Bacteria count on the therapist's palms increased during and after massage with and without the use of lubricant . There was no change in the case of no massage . (2) Bacteria count on the client's skin decreased during and after massage with the use of three different kinds of lubricants compared to the no-massage control . However, an increase was evident when no lubricant was used . (3) After hand washing with water for 20 seconds after each massage session, there were still bacteria on the therapist's palms . However, bacteria count differed with the type of lubricant used . CONCLUSION: Bacteria from the client's skin transferred to the therapist's hands during massage therapy . Bacteria count when no lubricant was used was greater than massage sessions using lubricants.

Arch Insect Biochem Physiol, 2004 Sep, 57(1), 15 - 27
Molecular cloning and bacterial expression of pheromone binding protein in the antennae of Helicoverpa armigera (Hübner); Wang GR et al.; A cDNA clone coding for pheromone binding protein was isolated from the antennae of Helicoverpa armigera by RT-PCR and (5'/3')-RACE technique . The full-length of H . armigera pheromone binding protein (HarmPBP) was 952 bp, possessing 162 amino acid residues including a signal peptide of 20 amino acids . Its predicted molecular weight and isoelectric point were 18.26 kDa and 5.23, respectively . This deduced amino acid sequence shared some common structural features with odorant-binding proteins from several moth species, including the six conserved cysteine motif, a typical characteristic of insect's odorant-binding proteins . Northern blot showed that HarmPBP is specifically expressed in the antennae of Helicoverpa armigera and more abundantly expressed in male than female . During the antennal development, HarmPBP is first expressed about 4 days prior to adult eclosion and rises to a plateau 2 days prior to adult eclosion . In order to obtain sufficient PBP for further determining its biochemical and physiological properties, a bacterical expression vector of PBP was constructed and successfully expressed in Escherichia coli . The recombinant PBP was shown to cross-react with an anti-PBP antiserum from Antheraea polyphemus . Polyclonal antibodies against HarmPBP were used to mark the distribution of the protein in olfactory sensilla . Very strong labeling was observed in the sensillum lymph of the hair lumen and of the sensillum-lymph cavity . In the male, HarmPBP is expressed in sensilla trichodea and not in sensilla basiconica, while in the female, it is expressed both in sensilla basiconica and sensilla trichodea.

Biotechnol Bioeng, 2004 Sep 5, 87(5), 602 - 13
Change of extracellular cAMP concentration is a sensitive reporter for bacterial fitness in high-cell-density cultures of Escherichia coli; Lin H et al.; Guanosine-3',5'-tetraphosphate (ppGpp) and sigmaS, two regulators of the starvation response of Escherichia coli, have received increasing attention for monitoring cell physiological changes in production processes, although both are difficult to quantify . The kinetics of cAMP formation and degradation were not yet investigated in such processes, although the complex regulation of cAMP by synthesis, release, and degradation in connection with straightforward methods for analysis renders it a highly informative target . Therefore, we followed the cAMP concentration in various nonrecombinant and in four different recombinant glucose-limited fed-batch processes in different production scales . The intracellular cAMP concentration increases strongly at the end of the batch phase . Most cAMP is released to the cultivation medium . The rates of accumulation and degradation of extracellular cAMP are growth-rate-dependent and show a distinct maximum at a growth rate of about 0.35 h(-1) . At very low growth rates, below 0.05 h(-1), extracellular cAMP is not produced but rather degraded, independent of whether this low growth rate is caused by glucose limitation or by the high metabolic load of recombinant protein production . In contrast to intracellular cAMP, which is highly unstable, analysis of extracellular cAMP is simpler and the kinetics of accumulation and degradation reflect well the physiological situation, including unlimited growth, limitation, and severe starvation of a production host.

Pediatr Radiol, 2005 Feb, 35(2), 198 - 201 Epub 2004 Sep 04.
Primary bacterial peritonitis in otherwise healthy children: imaging findings; Dann PH et al.; We report the imaging findings of two recent cases of primary bacterial peritonitis in otherwise healthy children with a clinical presentation mimicking acute appendicitis . Primary bacterial peritonitis is rare in the absence of underlying systemic disease . Although it has been described in the pediatric literature, the imaging findings have not been described in the radiological literature to the best of our knowledge . With imaging playing an increasing role in the evaluation of appendicitis in children, it is important for the radiologist to be familiar with this inflammatory process.

Biosystems, 2004 Aug-Oct, 76(1-3), 121 - 31
Parallelising a model of bacterial interaction and evolution; Gregory R et al.; Large simulations of bacterial colonies require huge amounts of computational time, the only way to achieve the necessary level of performance is with parallel computers and a suitably designed implementation that maps the problem onto the hardware . For real problems this mapping can be a non-trivial problem requiring careful consideration of the constraints in both the system being modelled and the hardware that executes that model . Here we describe an implementation of a system for modelling bacterial evolution that encompasses many physical scales . This system is composed entirely of individual entities all playing out a complex series of interactions . These individuals exist at the scale of the population of bacterial and at the gene product scale . This paper reports that it is possible to map a dynamic problem such as this onto fixed resources, for the most part making use of implicit multiplexing of resources provided by the OS and partitioning the problem to reduce communication time . Through this an efficient simulation can be created, making maximal use of the available hardware without constraining the model to require excessively specific resources.

Pediatr Neurol, 2004 Sep, 31(3), 165 - 71
Seizures complicating infantile and childhood bacterial meningitis; Chang CJ et al.; In this study, 116 patients, at least 1 month of age but younger than 5 years, were identified with culture-proven bacterial meningitis . A comparison was made between the clinical data of the patients with and without seizures during hospitalization . Seizures during acute bacterial meningitis accounted for 47% (55/116) of the episodes . Time interval between the onset of bacterial meningitis and that of seizures was 1 to 20 days (mean, 4 days) . Twelve of these 55 patients had one or more afebrile seizures after completing the treatment . At follow-up of at least 1 year after completing treatment, 26 patients had good outcomes, whereas the other 29 patients had poor outcomes . A strong correlation between the findings of abnormalities through neuroimaging and the occurrence of seizures during hospitalization was observed . The long-term outcomes of patients with infantile and childhood bacterial meningitis, who had seizures during the acute phase of bacterial meningitis, were worse than the outcomes of those who did not have such seizures . No child developed late seizures unless there were acute seizures . Factors associated with seizures during acute bacterial meningitis include disturbed consciousness on admission, abnormal neuroimaging findings, and low glucose and high concentration of total proteins in cerebrospinal fluid.

Trends Cell Biol, 2004 Sep, 14(9), 478 - 82
Modulated receptor interactions in bacterial transmembrane signaling; Webre DJ et al.; Bacteria can detect and respond to a remarkably diverse set of environmental conditions . This ability enables motile species to integrate stimuli, to compare current surroundings with those of the recent past, and to adjust swimming behavior to move up gradients of attractants and avoid repellents . Many of the molecular details involved in the bacterial chemotaxis system have been elucidated . Several models have been proposed recently to explain how cells process external information through a patch of highly interactive transmembrane receptors and transduce this information to other components in the cytoplasm that, in turn, function to regulate motility.

Rev Med Liege, 2004 Jun, 59(6), 403 - 6
{How I treat.. . the critical bacterial colonization of a leg ulcer . The Yin and the Yang features of silver-based dressings}; Pierard-Franchimont C et al.; The critical bacterial colonizaion of leg ulcers can impair their healing rate, aggravate the patient discomfort and increase the medical and nursing costs . In recent times, the dressings designed for leg ulcers have followed a pace of conceptual revolution . Some of them are now offered containing an antiseptic of the silver salt family . The silver concentraton delivered into the wound bed is important to consider when assessing treatment efficacy . The diversity of the silver-based dressings currently on the European market is as large as their differences in activity . Only a minority of these dressings adequately control the wound biocenosis . Their cost which is high for the patient, must be compared to that of nursing care that may become less important . The expected beneficit is a reduction in healing time.

Zh Mikrobiol Epidemiol Immunobiol, 2004 May-Jun, (3), 98 - 105
{Molecular aspects of the damaging action of bacterial lipopolysaccharides}; Riabichenko EV et al.; The review deals with the molecular aspects of the interaction of bacterial lipopolysaccharides (LPS, with the macroorganism: the sources of LPS in the organism, its detoxication, regulation disturbances in pathology (septic shock) . Special attention is drawn to the complex functioning of cytokines in the development of the inflammatory process both at the initial stage, characterized by the initiation of the cytokine cascade and at the final stage resulting in convalescence or the development of pathology . The most promising trends of research in this field are discussed.

J Biol Chem, 2004 Nov 12, 279(46), 48434 - 42 Epub 2004 Sep 01.
Nuclear import of proinflammatory transcription factors is required for massive liver apoptosis induced by bacterial lipopolysaccharide; Liu D et al.; Stimulation of macrophages with lipopolysaccharide (LPS) leads to the production of cytokines that elicit massive liver apoptosis . We investigated the in vivo role of stress-responsive transcription factors (SRTFs) in this process focusing on the precipitating events that are sensitive to a cell-permeant peptide inhibitor of SRTF nuclear import (cSN50) . In the absence of cSN50, mice challenged with LPS displayed very early bursts of inflammatory cytokines/chemokines, tumor necrosis factor alpha (1 h), interleukin 6 (2 h), interleukin 1 beta (2 h), and monocyte chemoattractant protein 1 (2 h) . Activation of both initiator caspases 8 and 9 and effector caspase 3 was noted 4 h later when full-blown DNA fragmentation and chromatin condensation were first observed (6 h) . At this time an increase of pro-apoptotic Bax gene expression was observed . It was preceded by a decrease of anti-apoptotic Bcl2 and BclX(L) gene transcripts . Massive apoptosis was accompanied by microvascular injury manifested by hemorrhagic necrosis and a precipitous drop in blood platelets observed at 6 h . An increase in fibrinogen/fibrin degradation products and a rise in plasminogen activator inhibitor 1 occurred between 4 and 6 h . Inhibition of SRTFs nuclear import with the cSN50 peptide abrogated all these changes and increased survival from 7 to 71% . Thus, the nuclear import of SRTFs induced by LPS is a prerequisite for activation of the genetic program that governs cytokines/chemokines production, liver apoptosis, microvascular injury, and death . These results should facilitate the rational design of drugs that protect the liver from inflammation-driven apoptosis.

FASEB J, 2004 Nov, 18(14), 1776 - 8 Epub 2004 Sep 02.
CpG motifs in bacterial DNA delay apoptosis of neutrophil granulocytes; Jozsef L et al.; Human neutrophil granulocytes die rapidly, and their survival is contingent upon rescue from programmed cell death by signals from the environment . We now show that a novel signal for delaying neutrophil apoptosis is unmethylated CpG motifs prevalent in bacterial DNA (CpG- DNA) . Human neutrophils express toll-like receptor 9 that recognizes these motifs . CpG-DNA, but not mammalian DNA or methylated bacterial DNA, markedly enhanced neutrophil viability by delaying spontaneous apoptosis . Endosomal maturation of CpG-DNA is prerequisite for these actions and was coupled to concurrent activation of the extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3-kinase/Akt signaling pathways, leading to phosphorylation of BAD at Ser112 and Ser136, respectively, and to prevention of decreases in mitochondrial transmembrane potential, cytochrome c release and caspase-3 activation . Consistently, pharmacological inhibition of either ERK or phosphatidylinositol 3-kinase partially reversed these actions of CpG-DNA; however, they did not produce additive inhibition . Furthermore, intravenous injection of CpG-DNA (200 microg/kg) into rats evoked slight decreases in blood pressure and induced a modest leukocytosis, whereas it effectively suppressed neutrophil apoptosis as assayed ex vivo . Our results indicate that unmethylated CpG motifs in bacterial DNA promote neutrophil survival by suppressing the apoptotic machinery and may therefore contribute to prolongation and amplification of inflammation.

Biophys J, 2004 Sep, 87(3), 1578 - 95
Effects of receptor interaction in bacterial chemotaxis; Mello BA et al.; Signaling in bacterial chemotaxis is mediated by several types of transmembrane chemoreceptors . The chemoreceptors form tight polar clusters whose functions are of great biological interest . Here, we study the general properties of a chemotaxis model that includes interaction between neighboring chemoreceptors within a receptor cluster and the appropriate receptor methylation and demethylation dynamics to maintain (near) perfect adaptation . We find that, depending on the receptor coupling strength, there are two steady-state phases in the model: a stationary phase and an oscillatory phase . The mechanism for the existence of the two phases is understood analytically . Two important phenomena in transient response, the overshoot in response to a pulse stimulus and the high gain in response to sustained changes in external ligand concentrations, can be explained in our model, and the mechanisms for these two seemingly different phenomena are found to be closely related . The model also naturally accounts for several key in vitro response experiments and the recent in vivo fluorescence resonance energy transfer experiments for various mutant strains . Quantitatively, our study reveals possible choices of parameters for fitting the existing experiments and suggests future experiments to test the model predictions.

Microb Cell Fact . 2004 Sep 2;3(1):11.
Strategies for the recovery of active proteins through refolding of bacterial inclusion body proteins; Vallejo LF et al.; Recent advances in generating active proteins through refolding of bacterial inclusion body proteins are summarized in conjunction with a short overview on inclusion body isolation and solubilization procedures . In particular, the pros and cons of well-established robust refolding techniques such as direct dilution as well as less common ones such as diafiltration or chromatographic processes including size exclusion chromatography, matrix- or affinity-based techniques and hydrophobic interaction chromatography are discussed . Moreover, the effect of physical variables (temperature and pressure) as well as the presence of buffer additives on the refolding process is elucidated . In particular, the impact of protein stabilizing or destabilizing low- and high-molecular weight additives as well as micellar and liposomal systems on protein refolding is illustrated . Also, techniques mimicking the principles encountered during in vivo folding such as processes based on natural and artificial chaperones and propeptide-assisted protein refolding are presented . Moreover, the special requirements for the generation of disulfide bonded proteins and the specific problems and solutions, which arise during process integration are discussed . Finally, the different strategies are examined regarding their applicability for large-scale production processes or high-throughput screening procedures.

Environ Microbiol, 2004 Oct, 6(10), 1005 - 20
Illuminating the detection chain of bacterial bioreporters; van der Meer JR et al.; Engineering bacteria for measuring chemicals of environmental or toxicological concern (bioreporter bacteria) has grown slowly into a mature research area . Despite many potential advantages, current bioreporters do not perform well enough to comply with environmental detection standards . Basically, the reasons for this are the lack of engineering principles in the detection chain in the bioreporters . Here, we dissect critical steps in the detection chain and illustrate how bioreporter design could be improved by mutagenizing specificity and selectivity of the sensing and regulatory proteins, by newer expression strategies and application of different signalling networks . Furthermore, we describe how redesigning bioreporter assays with respect to pollutant transport into the cells and application of other detection devices can decrease detection limits and increase the speed of detection.

J Mal Vasc, 2004 Jul, 29(3), 162 - 4
{Arteriovenous fistula of the renal vessels due to septic embolism in a patient with bacterial endocarditis}; Lacombe M et al.; A 27 year-old woman developed acute pain of the right flank during the course of an infectious endocarditis . A septic arteriovenous fistula of the renal vessels of a solitary functioning kidney was demonstrated . The cardiac valvular lesions required a prosthetic aortic and mitral replacement valves . An attempt to occlude the fistula by embolization with several coils was unsuccessful and led to surgery: extracorporeal repair enabled complete closure of the fistula . During the long-term follow-up, the aortic prosthetic valve had to be changed . Renal function was satisfactory and remained stable over time . Renal arteriovenous fistula is an exceptional complication of bacterial endocarditis despite the frequency of septic emboli during the course of the disease.

J Bacteriol, 2004 Sep, 186(18), 6316 - 9
Bacterial thymidylate synthase with intein, group II Intron, and distinctive ThyX motifs; Liu XQ et al.; The ThyX class of thymidylate synthases was previously characterized by a common ThyX motif, RHRX7S . We report bacterial ThyX sequences having distinctive ThyX motifs, suggesting a more general ThyX motif, R/THRX7-8S . One ThyX sequence has an intein in its ThyX motif that was shown to do protein splicing and a group II intron in its gene, suggesting a hot spot for these self-splicing mobile elements.

Mol Microbiol, 2004 Sep, 53(6), 1677 - 93
A mycobacterial virulence gene cluster extending RD1 is required for cytolysis, bacterial spreading and ESAT-6 secretion; Gao LY et al.; Initiation and maintenance of infection by mycobacteria in susceptible hosts are not well understood . A screen of Mycobacterium marinum transposon mutant library led to isolation of eight mutants that failed to cause haemolysis, all of which had transposon insertions in genes homologous to a region between Rv3866 and Rv3881c in Mycobacterium tuberculosis, which encompasses RD1 (Rv3871-Rv3879c), a known virulence gene cluster . The M . marinum mutants showed decreased virulence in vivo and failed to secrete ESAT-6, like M . tuberculosis RD1 mutants . M . marinum mutants in genes homologous to Rv3866-Rv3868 also failed to accumulate intracellular ESAT-6, suggesting a possible role for those genes in synthesis or stability of the protein . These transposon mutants and an ESAT-6/CFP-10 deletion mutant all showed reduced cytolysis and cytotoxicity to macrophages and significantly decreased intracellular growth at late stages of the infection only when the cells were infected at low multiplicity of infection, suggesting a defect in spreading . Direct evidence for cell-to-cell spread by wild-type M . marinum was obtained by microscopic detection in macrophage and epithelial monolayers, but the mutants all were defective in this assay . Expression of M . tuberculosis homologues complemented the corresponding M . marinum mutants, emphasizing the functional similarities between M . tuberculosis and M . marinum genes in this region that we designate extRD1 (extended RD1) . We suggest that diminished membranolytic activity and defective spreading is a mechanism for the attenuation of the extRD1 mutants . These results extend recent findings on the genomic boundaries and functions of M . tuberculosis RD1 and establish a molecular cellular basis for the role that extRD1 plays in mycobacterial virulence . Disruption of the M . marinum homologue of Rv3881c, not previously implicated in virulence, led to a much more attenuated phenotype in macrophages and in vivo, suggesting that this gene plays additional roles in M . marinum survival in the host.

Mol Microbiol, 2004 Sep, 53(6), 1641 - 60
Ralstonia solanacearum genes induced during growth in tomato: an inside view of bacterial wilt; Brown DG et al.; The phytopathogen Ralstonia solanacearum has over 5000 genes, many of which probably facilitate bacterial wilt disease development . Using in vivo expression technology (IVET), we screened a library of 133 200 R . solanacearum strain K60 promoter fusions and isolated approximately 900 fusions expressed during bacterial growth in tomato plants . Sequence analysis of 307 fusions revealed 153 unique in planta-expressed (ipx) genes . These genes included seven previously identified virulence genes (pehR, vsrB, vsrD, rpoS, hrcC, pme and gspK) as well as seven additional putative virulence factors . A significant number of ipx genes may reflect adaptation to the host xylem environment; 19.6%ipx genes are predicted to encode proteins with metabolic and/or transport functions, and 9.8%ipx genes encode proteins possibly involved in stress responses . Many ipx genes (18%) encode putative transmembrane proteins . A majority of ipx genes isolated encode proteins of unknown function, and 13% were unique to R . solanacearum . The ipx genes were variably induced in planta; beta-glucuronidase reporter gene expression analysis of a subset of 44 ipx fusions revealed that in planta expression levels were between two- and 37-fold higher than in culture . The expression of many ipx genes was subject to known R . solanacearum virulence regulators . Of 32 fusions tested, 28 were affected by at least one virulence regulator; several fusions were controlled by multiple regulators . Two ipx fusion strains isolated in this screen were reduced in virulence on tomato, indicating that gene(s) important for bacterial wilt pathogenesis were interrupted by the IVET insertion; mutations in other ipx genes are necessary to determine their roles in virulence and in planta growth . Collectively, this profile of ipx genes suggests that in its host, R . solanacearum confronts and overcomes a stressful and nutrient-poor environment.

Biophys J, 2004 Nov, 87(5), 3600 - 7 Epub 2004 Aug 31.
Structure and transport mechanism of the bacterial oxalate transporter OxlT; Hirai T et al.; Membrane proteins that belong to the major facilitator superfamily (MFS) are found in organisms across the evolutionary spectrum and mediate the transport of a variety of substrates ranging from small metabolites to neurotransmitters . The oxalate transporter (OxlT) is a representative MFS protein, and exchanges formate for oxalate across the cytoplasmic membrane of the organism Oxalobacter formigenes . Here, we present a structural model for the protein conformational changes that occur during oxalate transport by combining a three-dimensional map of the oxalate-bound, "closed" state of OxlT at 6.5 A determined by cryo-electron microscopy with a model of the "open" state of OxlT based on the atomic structures of the related transporters, glycerol-3-phosphate transporter (GlpT) and lactose permease (LacY) . We demonstrate that the principal structural change associated with substrate transport is a concerted rocking movement of the two structurally similar halves of the protein relative to each other . Our structural model places two positively charged residues, Arg-272 and Lys-355 in the central cavity, suggesting that electrostatic interactions between these residues and the oxalate anion is a key step in generating the conformational change between the open and closed states of the transporter.

Photochem Photobiol, 2004 Jul-Aug, 80, 7 - 14
Structural heterogeneity of cryotrapped intermediates in the bacterial blue light photoreceptor, photoactive yellow protein; Anderson S et al.; We investigate by X-ray crystallographic techniques the cryotrapped states that accumulate on controlled illumination of the blue light photoreceptor, photoactive yellow protein (PYP), at 110 K in both the wild-type species and its E46Q mutant . These states are related to those that occur during the chromophore isomerization process in the PYP photocycle at room temperature . The structures present in such states were determined at high resolution, 0.95-1.05A . In both wild type and mutant PYP, the cryotrapped state is not composed of a single, quasitransition state structure but rather of a heterogeneous mixture of three species in addition to the ground state structure . We identify and refine these three photoactivated species under the assumption that the structural changes are limited to simple isomerization events of the chromophore that otherwise retains chemical bonding similar to that in the ground state . The refined chromophore models are essentially identical in the wild type and the E46Q mutant, which implies that the early stages of their photocycle mechanisms are the same.

Arch Microbiol, 2004 Nov, 182(5), 373 - 87 Epub 2004 Aug 25.
Chemolithoautotrophy in the marine, magnetotactic bacterial strains MV-1 and MV-2; Bazylinski DA et al.; Magnetite-producing magnetotactic bacteria collected from the oxic-anoxic transition zone of chemically stratified marine environments characterized by O2/H2S inverse double gradients, contained internal S-rich inclusions resembling elemental S globules, suggesting they oxidize reduced S compounds that could support autotrophy . Two strains of marine magnetotactic bacteria, MV-1 and MV-2, isolated from such sites grew in O2-gradient media with H2S or thiosulfate (S2O3(2-)) as electron sources and O2 as electron acceptor or anaerobically with S2O3(2-) and N2O as electron acceptor, with bicarbonate (HCO3-)/CO2 as sole C source . Cells grown with H2S contained S-rich inclusions . Cells oxidized S2O3(2-) to sulfate (SO4(2-)) . Both strains grew microaerobically with formate . Neither grew microaerobically with tetrathionate (S4O6(2-)), methanol, or Fe2+ as FeS, or siderite (FeCO3) . Growth with S2O3(2-) and radiolabeled 14C-HCO3- showed that cell C was derived from HCO3-/CO2 . Cell-free extracts showed ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO) activity . Southern blot analyses indicated the presence of a form II RubisCO (cbbM) but no form I (cbbL) in both strains . cbbM and cbbQ, a putative post-translational activator of RubisCO, were identified in MV-1 . MV-1 and MV-2 are thus chemolithoautotrophs that use the Calvin-Benson-Bassham pathway . cbbM was also identified in Magnetospirillum magnetotacticum . Thus, magnetotactic bacteria at the oxic-anoxic transition zone of chemically stratified aquatic environments are important in C cycling and primary productivity.

Carbohydr Res, 2004 Sep 13, 339(13), 2233 - 9
Synergistic interactions between the genetically modified bacterial polysaccharide P2 and carob or konjac mannan; Ridout M et al.; Rheological studies have confirmed that the bacterial polysaccharide P2, a genetically modified variant of the Acetobacter xylinum polysaccharide acetan, undergoes synergistic gelation with either of the plant polysaccharides carob or konjac mannan . X-ray fibre diffraction data shows that P2 can form a 5-fold helical structure of pitch 4.7nm and an axial rise per disaccharide repeat of 0.92nm . Optical rotation data demonstrate that P2 undergoes a coil-helix transition in solution and that deacylation enhances the stability of the helical structure in solution . Studies made on mixtures prepared at different temperatures and ionic strengths suggest that denaturation of the P2 helix favours interaction and gelation . Deacetylation of P2 enhances gelation . X-ray diffraction data for oriented fibres prepared from deacetylated P2-konjac mannan mixed films reveal a 6-fold helical structure of pitch 5.54nm with an axial rise per disaccharide repeat also of 0.92nm . This mixed helix provides direct evidence for binding between the two polysaccharides . P2 contains two sites of acetylation: one on the backbone and one on the sidechain . The former site of acetylation inhibits helix formation for P2 . It is suggested that this site of acetylation also inhibits formation of the mixed helix, explaining the enhanced gelation of mixtures on deacetylation.

J Hepatol, 2004 Sep, 41(3), 384 - 90
Effect of intravenous albumin on systemic and hepatic hemodynamics and vasoactive neurohormonal systems in patients with cirrhosis and spontaneous bacterial peritonitis; Fernandez J et al.; BACKGROUND/AIMS: Albumin administration prevents renal failure and improves survival in spontaneous bacterial peritonitis . This study characterizes the mechanisms of action of albumin in this condition . METHODS: Systemic and splanchnic hemodynamics, plasma renin activity and plasma concentration of interleukin-6, serum concentration of nitric oxide and ascitic fluid levels of nitric oxide and interleukin-6 were assessed at diagnosis and resolution of infection in 12 patients with spontaneous bacterial peritonitis treated with ceftriaxone plus albumin . At infection resolution there was a significant improvement in circulatory function, as indicated by a significant increase in mean arterial pressure (+8%, P=0.02), a fall in heart rate (-10%, P=0.01), a suppression of plasma renin activity (-67%, P=0.002) and a decrease in creatinine levels . These changes were related to both an increase in cardiac work (stroke work index: +18%, P=0.005) and in peripheral vascular resistance (+14%, P=0.05) . The improvement in cardiac function was due to an increase in filling . No significant changes were observed in portal pressure or hepatic blood flow . CONCLUSIONS: These results indicate that the beneficial effects of albumin administration on systemic hemodynamics and renal function in spontaneous bacterial peritonitis are related to both an improvement in cardiac function and a decrease in the degree of arterial vasodilation.

Intern Med, 2004 Jul, 43(7), 534 - 9
The role of bacterial infection in the pathogenesis of inflammatory bowel disease; Ohkusa T et al.; In the last decade, the dogma that no bacteria could grow in the acid milieu of the stomach has been destroyed by evidence that the infective agent, H . pylori, is responsible for gastric and duodenal disease . Studies on H . pylori infection suggest that some strains of intestinal bacteria may be responsible for intestinal ulceration and inflammation concomitant with inflammatory bowel diseases (IBD), i.e., ulcerative colitis and Crohn's disease . Evidence for pathophysiological roles for certain strains of luminal bacteria result from a number of IBD animal models . Recent studies on innate immunity, including toll-like receptors and NOD isoforms, suggest that bacterial infections may contribute to intestinal inflammation in genetically susceptible hosts . This brief review focuses on the bacterial pathogenesis and the role of innate immunity in the etiology of IBD's.

Arq Neuropsiquiatr, 2004 Sep, 62(3A), 630 - 4 Epub 2004 Aug 24.
{Risk factors for bacterial meningitis in the newborn}; Krebs VL et al.; The aim of this study is to describe the risk factors for bacterial meningitis in newborns, and to analyze the prevalence of these factors, considering or not the low birth weight presence . Fifty newborns with bacterial meningitis were analyzed, excluding the ones with meningomyelocele or congenital infection . In the statistical analysis, the Fisher's exact test was used, considering significant the p < 0.05 values . This study has shown that prematurity, low birth weight and presence of previous infectious diseases in the newborn or in the mother were important risk factors for meningitis . Among low birth weight newborns, invasive procedures, especially tracheal intubation, use of central venous catheter and previous use of antibiotics, were significantly associated to the meningitis occurrence . These results indicate that the improvement in the prenatal care and in the hospital infection control are measures of high importance in the decrease of the incidence of neonatal bacterial meningitis.

Oncogene, 2004 Oct 7, 23(46), 7679 - 90
Mechanistic aspects of mda-7/IL-24 cancer cell selectivity analysed via a bacterial fusion protein; Sauane M et al.; The human mda-7/IL-24 gene product is normally expressed in melanocytes and certain lymphocyte populations . Loss of expression, a distinctive feature of many tumor suppressor genes, has been documented at RNA and protein levels in association with melanoma progression both in vitro as well as in human tumor-derived material . The MDA-7/IL-24 protein undergoes post-translational processing, including removal of an amino-terminal 48-residue signal peptide and extensive glycosylation prior to its secretion by producing cells . Its inherent cytokine properties have been documented in multiple reports, which have identified and characterized its cognate receptors and activation of the JAK/STAT signaling pathway following ligand/receptor docking . A notable and incompletely understood property of MDA-7/IL-24 is its ability to induce apoptosis in transformed cells, while having marginal growth suppressive effects on normal primary or immortalized cell lines . MDA-7/IL-24 has been delivered to cells, tumor xenografts and patients in clinical trials via a nonreplicating adenovirus (Ad.mda-7) . Studies utilizing eukaryotically expressed and purified MDA-7/IL-24 protein from several sources have recapitulated some of the molecule's reported properties including receptor binding and JAK/STAT activation . Here, we report the properties and characteristics of a bacterially expressed and purified GST-MDA-7 fusion protein . These studies reveal that GST-MDA-7 retains its cancer-selective apoptosis-inducing properties, thereby providing a new reagent that will assist in defining the mechanism of action of this novel cytokine . In addition, retention of tumor-specific activity of GST-MDA-7 suggests that this protein may also have therapeutic applications.

J Leukoc Biol, 2004 Nov, 76(5), 994 - 1001 Epub 2004 Aug 26.
Bacterial endotoxin stimulates macrophages to release HMGB1 partly through CD14- and TNF-dependent mechanisms; Chen G et al.; Bacterial endotoxin {lipopolysaccharide (LPS)} stimulates macrophages to sequentially release early {tumor necrosis factor (TNF)} and late {high mobility group box 1 (HMGB1)} proinflammatory cytokines . The requirement of CD14 and mitogen-activated protein kinases {MAPK; e.g., p38 and extracellular signal-regulated kinase (ERK)1/2} for endotoxin-induced TNF production has been demonstrated previously, but little is known about their involvement in endotoxin-mediated HMGB1 release . Here, we demonstrated that genetic disruption of CD14 expression abrogated LPS-induced TNF production but only partially attenuated LPS-induced HMGB1 release in cultures of primary murine peritoneal macrophages . Pharmacological suppression of p38 or ERK1/2 MAPK with specific inhibitors (SB203580, SB202190, U0126, or PD98059) significantly attenuated LPS-induced TNF production but failed to inhibit LPS-induced HMGB1 release . Consistently, an endogenous, immunosuppressive molecule, spermine, failed to inhibit LPS-induced activation of p38 MAPK and yet, still significantly attenuated LPS-mediated HMGB1 release . Direct suppression of TNF activity with neutralizing antibodies or genetic disruption of TNF expression partially attenuated HMGB1 release from macrophages induced by LPS at lower concentrations (e.g., 10 ng/ml) . Taken together, these data suggest that LPS stimulates macrophages to release HMGB1 partly through CD14- and TNF-dependent mechanisms.

Rhizobia, Prokaryote, MIC, Bacterium, Bioreactor, Microbiology, Cell Biology, Microbes, Molecular Biology, Microorganisms, Listeria Monocytogenes, Microorganism, Environmental Microbiology, Microbe, f, Genome, j, Bacteria, o, Bioengineering, t, Bacteriology, p, Biofilter, Dna, Escherichia coli, g, Bactericidal, a, Thermophile, m, Culture medium, p, Enterobacteriacea, b, Minimal inhibiting concentration, c, Salmonella typhimurium, p, Escherichia coli, m, E. coli, s, Streptococci, b, Vibrio, s, Yeast, m, Escherichia coli, e, Lactobacillus, c, Antibiotic, c, Bacillus, p, Clostridia, g, Pasteurella, e, Rhizobacteria, s, Saccharomyces cerevisiae, a, Saccharomyces cerevisiae, m, Serratia, c, Pseudomonas aeruginosa, e, Cephalosporin, m, Pathogenic bacterium, a, Microflora, b, Gram negative, s, Antibiotic treatment, b, Vibrio, Streptococcus,

Scientific Publications - Work Done by Microbiology Reader Bioscreen C
Agricultural Microbiology Anaerobic Microbiology Antimicrobial Susceptibility Artificial Atmosphere Bioassay of Antibiotics Biofilm Microbiology Bioreactor Technology Biotechnology Cell Biology Clinical Microbiology Environmental Microbiology Experiments with Yeast	Fermentation Food Microbiology Functional Genomics Gene Technology Growth Media Development Growth Rate and Lag Time Industrial Microbiology Medical/Pharmaceutical Field Microbiological Assay Microbiological Research Microbiology of Cosmetics go to a specific theme...	Military Microbiology Molecular Microbiology Mutagenicity and Genotoxicity Oral Microbiology Patents Postantibiotic Studies Soil Microbiology Spore Microbiology Veterinary Microbiology Waste/Wastewater Treatment Water Microbiology Wine Microbiology

� 2005 Transgalactic Ltd (manufacturer of Bioscreen C software) | Privacy Statement | P.O. Box 1393, 00101 Helsinki, Finland, phone: +358 9 85172920, fax: +358 9 8749481, e-mail: microbiology@bionewsonline.com

Last modified: May 25, 2005