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| J Biol Chem, 2001 Dec 7, 276(49), 45513 - 5 Epub 2001 Oct 16. Revealing the involvement of extended hydrogen bond networks in the cooperative function between distant sites in bacterial reaction centers; Tandori J et al.; In reaction center proteins of photosynthetic bacteria, the amplitude of proton uptake induced by the one-electron reduction of either of the two quinone electron acceptors (Q(A) and Q(B)) is an intrinsic observable of the electrostatic interactions associated with the redox function of the complex . We report here that, in Rhodobacter capsulatus, complete restoration of proton uptake (upon formation of Q(A)(-) and Q(B)(-)) to the level found in the wild type is observed in a mutant reaction center in which a tyrosine substitution in the Q(A) environment (Ala(M274) --> Tyr) is coupled with mutations of acidic residues near Q(B) (Glu(L212) --> Ala/Asp(L213) --> Ala) that initially cancel the proton uptake above pH 8 . This result demonstrates that proton uptake occurs by strong cooperation between structural motifs, such as hydrogen-bonded networks, that span the 18 A distance between the two quinone acceptors. Curr Opin Biotechnol, 2001 Oct, 12(5), 467 - 72 Transfer of eukaryotic expression plasmids to mammalian host cells by bacterial carriers; Weiss S et al.; The concept of transkingom transfer of DNA from bacteria to other organisms has recently been extended to include eukaryotic host cells . Intracellular bacteria have been shown to transfer eukaryotic expression plasmids to mammalian host cells in vitro and in vivo . This can be used to induce immune responses towards protein antigens encoded by the plasmid, to complement genetic defects or even to direct the production of proteins in appropriate organs . The ease of generating such vehicles makes this a highly attractive area for further research. Ann Thorac Surg, 2001 Oct, 72(4), 1327 - 30 Autologous transfusion of shed mediastinal blood after coronary artery bypass grafting and bacterial contamination; Andreasen AS et al.; BACKGROUND: Autologous transfusion of shed mediastinal blood is often used after coronary artery bypass grafting (CABG) . Shed blood has in a few studies been cultured during the first postoperative hours . However, autologous transfusion might in some cases be continued for several hours and no study has yet examined the bacterial contamination of shed blood later than 6 hours postoperatively . METHODS: Seventy-five patients undergoing electively performed CABG were included . Cultures of shed blood were taken at initiation of the autologous transfusion and the following morning . Infection variables were measured preoperatively and postoperatively . Infectious complications during the first postoperative week were registered . RESULTS: The frequency of patients with bacterial growth in the first culture was 0.22 (95% confidence interval: 0.12 to 0.31) compared with 0.04 (95% confidence interval: -0.044 to 0.087) in the second culture (p < 0.002) . We found no significant difference in infection variables between patients with or without bacterial growth in the cultures . No patients suffered from early postoperative infectious complications . CONCLUSIONS: There is no further contamination of the shed blood during the period between initiating the autologous transfusion and the following morning. Urology . 2001 Oct;58(4):607. Massive hematuria due to right renal artery mycotic pseudoaneurysm in a patient with subacute bacterial endocarditis; Ohebshalom MM et al.; A 40-year-old woman with recently diagnosed bacterial endocarditis was admitted to the hospital with gross hematuria and anemia . Computed tomography revealed a large right upper pole renal artery pseudoaneurysm, a wedge-shaped hypoperfused region of the left kidney, and a splenic abscess . Radiographic embolization of the right renal artery was performed to stabilize the bleeding . The splenic abscess was drained . Subsequent right nephrectomy and splenectomy were performed for persistent leukocytosis . This unusual presentation of a septic embolus and its management are discussed. Biochim Biophys Acta, 2001 Nov 1, 1515(1), 44 - 54 Encapsulation of DNA in negatively charged liposomes and inhibition of bacterial gene expression with fluid liposome-encapsulated antisense oligonucleotides; Fillion P et al.; Antisense therapy for the treatment of bacterial infections is a very attractive alternative to overcome drug resistance problems . However, the penetration of antisense oligonucleotides into bacterial cells is a major huddle that has delayed research and application in this field . In the first part of this study, we defined efficient conditions to encapsulate plasmid DNA and antisense oligonucleotides in a fluid negatively charged liposome . Subsequently, we evaluated the potential of liposome-encapsulated antisense oligonucleotides to penetrate the bacterial outer membrane and to inhibit gene expression in bacteria . It was found that 48.9+/-12% and 43.5+/-4% of the purified plasmid DNA and antisense oligonucleotides were respectively encapsulated in the liposomes . Using fluorescence-activated cell sorting analysis, it was shown, after subtraction of the fluorescence values due to the aggregation phenomenon measured at 4 degrees C, that about 57% of bacterial cells had integrated the encapsulated antisense oligonucleotides whereas values for free antisenses were negligible . The uptake of the encapsulated anti-lacZ antisense oligonucleotides resulted in a 42% reduction of beta-galactosidase compared to 9% and 6% for the encapsulated mismatch antisense oligonucleotides and the free antisense oligonucleotides respectively . This work shows that it is possible to encapsulate relatively large quantities of negatively charged molecules in negative fluid liposomes and suggests that fluid liposomes could be used to deliver nucleic acids in bacteria to inhibit essential bacterial genes. Plant Cell, 2001 Oct, 13(10), 2257 - 68 Plastid division is driven by a complex mechanism that involves differential transition of the bacterial and eukaryotic division rings; Miyagishima Sy et al.; During plastid division, two structures have been detected at the division site in separate analyses . The plastid-dividing ring can be detected by transmission electron microscopy as two (or three) electron-dense rings: an outer ring on the cytosolic face of the outer envelope, occasionally a middle ring in the intermembrane space, and an inner ring on the stromal face of the inner envelope . The FtsZ ring, which plays a central role in bacterial division, also is involved in plastid division and is believed to have descended to plastids from cyanobacterial endosymbiosis . The relationship between the two structures is not known, although there is discussion regarding whether they are identical . Biochemical and immunocytochemical investigations, using synchronized chloroplasts of the red alga Cyanidioschyzon merolae, showed that the plastid FtsZ ring is distinct and separable from the plastid-dividing ring . The FtsZ ring localizes in stroma and faces the inner plastid-dividing ring at the far side from the inner envelope . The FtsZ ring and the inner and outer plastid-dividing rings form in that order before plastid division . The FtsZ ring disappears at the late stage of constriction before dissociation of the plastid-dividing ring, when the constriction is still in progress . Our results suggest that the FtsZ ring;-based system, which originated from a plastid ancestor, cyanobacteria, and the plastid-dividing ring;-based system, which probably originated from host eukaryotic cells, form a complex and are involved in plastid division by distinct modes. J Physiol Paris, 2001 Jan-Dec, 95(1-6), 443 - 51 Effects of dexamethasone and FK506 on Helicobacter pylori-induced gastritis and bacterial viability in Mongolian gerbils; Naka Y et al.; FK506 and dexamethasone were used to investigate whether or not immunosuppression affects H . pylori colonization and gastric mucosal damage induced by Helicobacter pylori in Mongolian gerbils . Two weeks after H . pylori infection, FK506 and dexamethasone or vehicle alone were subcutaneously administered once daily for the following 2 weeks . FK506 or vehicle alone was administered subcutaneously once daily for 5 weeks (1 week before and 4 weeks after infection) . In H . pylori-infected animals for 4 weeks, hemorrhagic erosions and inflammatory responses (neutrophil infiltration and lymphoid follicle formation) were induced in gastric mucosa at an incidence of 100% . Both FK506 and dexamethasone administered for 2 weeks markedly reduced such mucosal changes . In these animals, H . pylori viability in the stomach was significantly elevated . FK506 administered for 5 weeks also significantly inhibited the hemorrhagic erosions, edema and neutrophil infiltration in the stomach . H . pylori viability was slightly elevated as compared with the control . It was concluded that the host immune responses might play dual roles both by deteriorating gastritis induced by H . pylori and by protecting against H . pylori infection in its early stage. Biol Chem, 2001 Aug, 382(8), 1271 - 6 Photo-CIDNP 13C magic angle spinning NMR on bacterial reaction centres: exploring the electronic structure of the special pair and its surroundings; Matysik J et al.; Photochemically induced dynamic nuclear polarisation (photo-CIDNP) in intact bacterial reaction centres has been observed by 13C-solid state NMR under continuous illumination with white light . Strong intensity enhancement of 13C NMR signals of the aromatic rings allows probing the electronic ground state of the two BChl cofactors of the special pair at the molecular scale with atomic selectivity . Differences between the two BChl cofactors are discussed . Several aliphatic 13C atoms of cofactors, as well as 13C atoms of the imidazole ring of histidine residue(s), show nuclear-spin polarisation to the same extent as the aromatic nuclei of the cofactors . Mechanisms and applications of polarisation transfer are discussed. J Immunol, 2001 Oct 15, 167(8), 4644 - 50 Meningeal and perivascular macrophages of the central nervous system play a protective role during bacterial meningitis; Polfliet MM et al.; Meningeal (MM) and perivascular macrophages (PVM) constitute major populations of resident macrophages in the CNS that can be distinguished from microglial cells . So far, there is no direct evidence that demonstrates a possible role of MM and PVM in the CNS during normal or pathologic conditions . To elucidate the role of the MM and PVM during CNS inflammation, we have developed a strategy using a single intraventricular injection of mannosylated clodronate liposomes, which results in a complete and selective depletion of the PVM and MM from the CNS . Depletion of the MM and PVM during experimental pneumococcal meningitis resulted in increased illness, which correlated with higher bacteria counts in the cerebrospinal fluid and blood . This was associated with a decreased influx of leukocytes into the cerebrospinal fluid, which occurred despite an elevated production of relevant chemokines (e.g., macrophage-inflammatory protein-2) and a higher expression of vascular adhesion molecules (e.g., VCAM-1) . In contrast, the higher bacterial counts correlated with elevated production of local and systemic inflammatory mediators (e.g., IL-6) indicating enhanced local leukocyte and systemic immune activation, and this may explain the worsening of the clinical signs . These findings show that the PVM and MM play a protective role during bacterial meningitis and suggest that a primary action of these macrophages is to facilitate the influx of leukocytes at the blood-brain barrier . More in general, we demonstrate for the first time that the PVM and MM play a crucial role during inflammation in the CNS. Chest, 2001 Oct, 120(4), 1377 - 89 Bacterial/viral filtration: let the breather beware! Demers RR. Most clinicians believe that any device that is marketed as a "bacterial/viral filter" must necessarily be capable of capturing any individual bacteria or viruses that might be suspended within inhaled or exhaled gases . We were surprised to discover that this is, by no means, a justifiable assumption . This article describes testing methods that manufacturers employ to generate the often-misleading efficiency specifications that are claimed for some of these devices . We discuss articles that have documented the presence of airborne pathogens in the effluent of a ventilator circuit, and characterize the attributes that a competent filter must exhibit if it is to succeed in protecting patients and caregivers from incidental exposure to bacteria, viruses, aerosolized drugs, and endotoxins . This article continues with a discussion of the numbers of particles that are commonly produced with commercially available pneumatic nebulizers, the comparative performance characteristics of filters and heat/moisture exchanging filters (HMEFs), and the success or failure of various brands of HMEFs to comply with the guidelines recently developed by the Centers for Disease Control and Prevention for the management of patients who are harboring active tuberculosis . The presentation concludes with a description of the standards that apply to any filter that classifies as a high-efficiency particulate aerosol (HEPA) device, and demonstrates that the performance of filters/HMEFs in common clinical use can range from approximately 1/50th to > 30-fold the efficiency of a HEPA-grade device . Those who frequent the bedside of patients receiving ventilation might unwittingly be placing themselves at considerable risk of exposure to infectious microaerosols, but methods are available to dramatically decrease those risks. Pancreas, 2001 Oct, 23(3), 296 - 301 Inhibition of inducible nitric oxide synthase reduces bacterial translocation in a rat model of acute pancreatitis; Simsek I et al.; INTRODUCTION: Translocation of bacteria from the gut into pancreatic necrosis is an important factor in the development of septic complications and mortality in acute pancreatitis . S-methylisothiourea (SMT) is an inducible nitric oxide synthase inhibitor that has been shown to decrease bacteria} translocation in sepsis and thermal injury . AIM: To investigate whether SMT could affect bacterial translocation in acute necrotizing pancreatitis . METHODOLOGY: Forty-five Sprague-Dawley rats were studied . Acute pancreatitis was induced in Group I and Group II by injection of taurocholate and trypsin into the common biliopancreatic duct . Group III underwent laparotomy with the manipulation (but not cannulation) of the pancreas and received saline injection . Group I rats received normal saline as a placebo, and Group II rats received SMT after surgery for 2 days . At 48 hours, blood was drawn for serum amylase determinations . Bacterial translocation to mesenteric lymph nodes and distant sites (pancreas, liver, and peritoneum) were examined . A point scoring system of histologic features was used to evaluate the severity of pancreatitis . RESULTS: Plasma amylase levels and pancreatic histologic score were significantly reduced in Group II rats given SMT compared with those in Group I rats given saline (p < 0.01, p < 0.05, respectively) . All Group I rats had bacterial translocation to mesenteric lymph nodes compared with 7 of 12 rats in Group II (p < 0.05) . There was no difference in bacterial translocation to distant organs between the two groups, although rates tended to be lower in Group II compared with Group I (p > 0.05) . Bacterial counts in the pancreas were significantly reduced in Group II rats compared with those in Group I rats (p < 0.05) . CONCLUSION: Treatment with SMT appears to have ameliorated the course of acute pancreatitis; however, mortality was not affected. Bioinformatics, 2001 Sep, 17(9), 791 - 802 Comprehensive comparison between locations of orthologous genes on archaeal and bacterial genomes; Horimoto K et al.; MOTIVATION: Following an extensive search for orthologous genes between the complete genomes from archaea and bacteria, the spatial association of the orthologs has been investigated in terms of synteny, the conservation of the order of neighboring genes . However, the relationships between the relative locations of remote orthologs over entire genomes have not been shown . RESULTS: Comprehensive comparisons between the locations of orthologs on nineteen archaeal and bacterial genomes are presented by the location to location correspondence based on the gene-location distance . When the two genomes are rotated such that a pair of orthologs with the shortest distance is set in the same angle, a statistically significant number of orthologs maintain their relative locations between the genomes . Even by the short distances at the 5% significance level, the rotations are restricted within a narrow range, suggesting an intrinsic angle for realizing similar locations between the orthologs in each genome pair . Furthermore, the rotations in the restricted range agree with the replication origin and terminus sites for the analyzed genomes where such sites are known . The relationship between location-maintained orthologs and gene function is also discussed. Trends Biochem Sci, 2001 Oct, 26(10), 579 - 82 The CHASE domain: a predicted ligand-binding module in plant cytokinin receptors and other eukaryotic and bacterial receptors; Anantharaman V et al.; A novel, 200-230 amino acid extracellular domain was identified in the plant cytokinin receptor Cre1, in the receptor-histidine kinase DhkA and the adenylyl cyclase Acg from the slime mold Dictyostelium discoideum, and in a variety of other receptor-like proteins from bacteria and eukaryotes . The domain is predicted to bind diverse low molecular weight ligands, such as the cytokinin-like adenine derivatives or peptides, and mediate signal transduction through the respective receptors. J Clin Gastroenterol, 2001 Oct, 33(4), 295 - 8 Long-term prognosis of cirrhosis after spontaneous bacterial peritonitis treated with ceftriaxone; Franca AV et al.; Spontaneous bacterial peritonitis (SBP) is a frequent infection in cirrhotic patients with ascites, with a poor prognosis . The aims of this study were to determine the long-term survival of cirrhotic patients with SBP treated with ceftriaxone and to identify predictive factors related to survival . We studied 47 first episodes of SBP treated with ceftriaxone with a mean follow-up of 272 days . Nineteen variables were recorded to evaluate their relation to survival . The most frequent organism that caused SBP was Escherichia coli (40%) . Spontaneous bacterial peritonitis resolution was achieved in 67% of patients . After resolution, SBP recurrence was observed in 44% of patients . The cumulative probability of survival was 68.1% at 1 month and 30.8% at 6 months . After uni-and multivariate analyses of all cases, SBP resolution ( p = 0.0001) and international normalized ratio (INR) ( p = 0.0057) were found to be related to survival . Another analysis performed after SBP resolution and SBP recurrence showed that ascitic fluid-positive culture ( p = 0.0344) and INR ( p = 0.0218) had statistical significance as variables predictive of long-term survival . We conclude that the survival of cirrhotic patients is very short after the first episode of SBP, a fact probably related to advanced liver disease, as liver dysfunction (INR) is the most important factor related to long-term patient survival. Curr Opin Microbiol, 2001 Oct, 4(5), 602 - 6 The relative contributions of recombination and point mutation to the diversification of bacterial clones; Spratt BG et al.; Low levels of recombination in bacterial species have often been inferred from the presence of linkage disequilibrium between the alleles at different loci in the population . However, significant linkage disequilibrium is inevitable in organisms that divide by binary fission, and recombinational replacements must be very frequent, compared to point mutation, to dissipate disequilibrium . Recent studies using data from multilocus sequence typing indicate that, in many species, recombinational replacements contribute more greatly to clonal diversification than do point mutations and, in some species, recombination has been sufficient to eliminate any phylogenetic signal from gene trees . Recent efforts to improve understanding of the extent and impact of homologous recombination in the diversification of bacterial clones are discussed. Trends Genet, 2001 Oct, 17(10), 589 - 96 Deletional bias and the evolution of bacterial genomes; Mira A et al.; Although bacteria increase their DNA content through horizontal transfer and gene duplication, their genomes remain small and, in particular, lack nonfunctional sequences . This pattern is most readily explained by a pervasive bias towards higher numbers of deletions than insertions . When selection is not strong enough to maintain them, genes are lost in large deletions or inactivated and subsequently eroded . Gene inactivation and loss are particularly apparent in obligate parasites and symbionts, in which dramatic reductions in genome size can result not from selection to lose DNA, but from decreased selection to maintain gene functionality . Here we discuss the evidence showing that deletional bias is a major force that shapes bacterial genomes. Mutat Res, 2001 May 10, 485(4), 331 - 8 Characterization of functional interactions among the Escherichia coli mismatch repair proteins using a bacterial two-hybrid assay; Mansour CA et al.; Vsr mediates very short patch repair in Escherichia coli, correcting T/G mismatches caused by deamination of 5-methylcytosine to thymine . MutS and MutL, part of the post-replication mismatch repair system, stimulate VSP repair . In this study, we use a bacterial two-hybrid assay to show that MutL interacts with Vsr . We also show that interaction between Vsr and MutL inhibits the ability of MutL to dimerize, to interact with MutS and MutH and to mediate a previously unknown interaction between MutS and MutH . This inhibition may explain why high levels of Vsr are mutagenic in vivo . In addition, we show that the Mut fusion proteins are repair proficient in the bacterial two-hybrid assay, making it possible to study their interactions in various genetic backgrounds, or in the presence of DNA damaging agents. Biochemistry, 2001 Oct 9, 40(40), 12132 - 9 Manipulating the direction of electron transfer in the bacterial reaction center by swapping Phe for Tyr near BChl(M) (L181) and Tyr for Phe near BChl(L) (M208); Kirmaier C et al.; We have investigated the primary charge separation processes in Rb . capsulatus reaction centers (RCs) bearing the mutations Phe(L181) --> Tyr, Tyr(M208) --> Phe, and Leu(M212) --> His . In the YFH mutant, decay of the excited primary electron donor P occurs with an 11 +/- 2 ps time constant and is trifurcated to give (1) internal conversion to the ground state ( approximately 10% yield), (2) charge separation to the L side of the RC ( approximately 60% yield), and (3) electron transfer to the M-side bacteriopheophytin BPh(M) ( approximately 30% yield) . These results relate previous work in which the ionizable residues Lys (at L178) and Asp (at M201) have been used to facilitate charge separation to the M side of the RC, and the widely studied L181 and M208 mutants . One conclusion that comes from this work is that the Tyr (M208) --> Phe and Gly(M201) --> Asp mutations near the L-side bacteriochlorophyll (BChl(L)) raise the free energy of P(+)BChl(L)(-) by comparable amounts . The results also suggest that the free energy of P(+)BChl(M)(-) is lowered more substantially by a Tyr at L181 than a Lys at L178 . The results on the YFH mutant further demonstrate that the free energy differences between the L- and M-side charge-separated states play a significant role in the directionality of charge separation in the wild-type RC, and place limits on the contributing role of differential electronic matrix elements on the two sides of the RC. An Esp Pediatr, 2001 Oct, 55(4), 321 - 8 {Procalcitonin in the early diagnosis of invasive bacterial infection in febrile infants}; Fernandez Lopez A et al.; BACKGROUND: Procalcitonin (PCT) it is a new marker of bacterial infection . Because of its shorter half-life and earlier ascent it offers advantages over C-reactive protein (CRP) . OBJECTIVE: To compare the diagnostic performance of PCT in the early detection of invasive bacterial infection in infants with that of CPR . MATERIAL AND METHODS: Between January of 1998 and February of 2000 we performed a prospective observational study in the emergency department of infants aged between 1 and 36 months who had been treated for fever and for whom PCT and CRP plasmatic values had been obtained . Plasmatic PCT and PCR values were evaluated and correlated with the final diagnosis . ROC curves for both markers were calculated . RESULTS: One hundred infants with a mean age of 8.8 months (SD 7.59) were included in four groups of 25 patients each (viral infection, localized bacterial infection, invasive bacterial infection and control group) . The mean PCT and CRP values in invasive bacterial infections {PCT: 14.45 ng/mL (SD 27.95) and CRP: 95.10 mg/L (SD 7 2.77)} were significantly higher than in non-invasive infections {PCT: 0.27 ng/mL (SD 0.19) and CRP: 25.67 mg/L (SD 33.04)} but the diagnostic performance of PCT was better . The area under the curve for PCT was 0.95 (SD 0.03), which was significantly higher (p < 0.001) than that obtained for CRP {0.81 (SD 0.05)} . The optimal cut-off for PCT was > 0.4 ng/mL (sensitivity: 95.5 %; specificity: 86.4 %) and that for CRP was > 42.9 mg/L (sensitivity: 75 %; specificity: 81.8 %) . In infants who had fever for less than 12 hours (n 30) the area under the curve for PCT was 0.90 (SD 0.06), which was higher (p < 0.001) than that for PCR {0.64 (SD 0.11)} . The optimal cut-off for PCT in this group was > 0.4 ng/mL (sensitivity: 90 %; specificity: 94 %) and that for CRP was > 26.6 mg/L (sensitivity: 60 %; specificity: 77.8 %) . CONCLUSIONS: The diagnostic performance of PCT was higher than that of CRP in the early detection of invasive infection in febrile infants, even when evolution was less than 12 hours. Clin Infect Dis, 2001 Nov 1, 33(9), e109 - 11 Epub 2001 Sep 26. Cerebrospinal fluid penetration of levofloxacin in patients with spontaneous acute bacterial meningitis; Scotton PG et al.; We have assessed levofloxacin penetration in cerebrospinal fluid (CSF) and the liquor-to-plasma ratio (C(L)/C(P)) at 2 hours after dosing in 5 patients with spontaneous acute bacterial meningitis . CSF levofloxacin concentration at 2 hours after dosing was 1.99+/-0.67 microg/mL, and the C(L)/C(P) at 2 hours after dosing was 0.34+/-0.09. J Microbiol Methods, 2001 Nov, 47(2), 219 - 31 Comparison of methods for monitoring bacterial transport in the subsurface; DeFlaun MF et al.; The purpose of this study was to compare in a laboratory experiment, a suite of methods developed to track viable bacteria during field transport experiments . The criteria for development and selection of these methods included: (1) the ability to track bacteria within the environment from which they were isolated; (2) the lack of any effect upon the viability or the transport characteristics of the strain; (3) low detection limits; (4) a quantification range that covered several orders of magnitude; and (5) an analytical cost and turnover time commensurate with the analysis of several thousands of samples in a few months . The approaches developed included: enumeration of bacteria labeled with a vital fluorescent stain (CFDA/SE) using microplate spectrofluorometry, flow cytometry, and ferrographic (immunomagnetic) capture; enumeration of highly (13)C-enriched bacteria using combustion-IRMS; and quantitative PCR . These methods were compared to direct microscopic enumeration and plate counts during a bacterial transport experiment performed in an intact sediment core and designed to simulate the field experiment . Four of the seven methods had equivalent recoveries for the breakthrough of a pulse of bacteria eluting from a 50-cm long sediment core, and all of the methods detected the arrival of cells in the effluent prior to the conservative tracer . Combustion IRMS and ferrographic enumeration had the lowest quantification limits (approximately 2 to 20 cells/ml), whereas microplate spectrofluorometry had the highest quantification limit (approximately 10(5) cells/ml) . These methods have the potential for numerous applications beyond tracking bacteria injected into the subsurface. Obstet Gynecol, 2001 Oct, 98(4), 656 - 63 Longitudinal analysis of bacterial vaginosis: findings from the HIV epidemiology research study; Jamieson DJ et al.; OBJECTIVE: To determine the natural history of bacterial vaginosis in women with or at risk for human immunodeficiency virus (HIV) . METHODS: A cohort of 854 HIV-infected women and 434 HIV-uninfected women from four US sites was followed prospectively with gynecologic exams every 6 months over a 5-year period . The prevalence, incidence, persistence, and severity of bacterial vaginosis, which was defined using a Gram-staining scoring system, were calculated using generalized estimating equation methods . RESULTS: In adjusted analyses, HIV-infected women had a higher prevalence of bacterial vaginosis than HIV-uninfected women (adjusted odds ratio {OR} 1.29; 95% confidence interval {CI} 1.08, 1.55) . Although HIV-infected women were not more likely to have incident infections, they were more likely to have persistence of their infections (adjusted OR 1.49; 95% CI 1.18, 1.89) . Similarly, immunocompromised women (CD4+ cell count less than 200 cells/microL) were more likely than HIV-infected women with higher CD4+ cell counts (more than 500 cells/microL) to have prevalent (adjusted OR 1.29; 95% CI 1.03, 1.60) and persistent (adjusted OR 1.38; 95% CI 1.01, 1.91) bacterial vaginosis infections, but not more likely to have incident infections . Immunocompromised women had more severe bacterial vaginosis by both clinical criteria (adjusted OR 1.40; 95% CI 1.08, 1.82) and by Gram-staining criteria (adjusted OR 1.50; 95% CI 1.12, 2.00) . CONCLUSIONS: Bacterial vaginosis is more prevalent and persistent among HIV-infected women, particularly among those who are immunocompromised . Immunocompromised women are more likely than HIV-infected women with higher CD4+ cell counts to have severe bacterial vaginosis. FEBS Lett, 2001 Sep 21, 505(3), 353 - 6 The central plug in the reconstituted undecameric c cylinder of a bacterial ATP synthase consists of phospholipids; Meier T et al.; The isolated rotor cylinder of the ATP synthase from Ilyobacter tartaricus was reconstituted into two-dimensional crystalline arrays . Atomic force microscopy imaging indicated a central cavity on one side of the rotor and a central plug protruding from the other side . Upon incubation with phospholipase C, the plug disappeared, but the appearance of the surrounding c subunit oligomer was not affected . This indicates that the plug consists of phospholipids . As the detergent-purified c cylinder is completely devoid of phospholipids, these are incorporated into the central hole from one side of the cylinder during the reconstitution procedure. Am J Public Health, 2001 Oct, 91(10), 1664 - 70 Factors linked to bacterial vaginosis in nonpregnant women; Holzman C et al.; OBJECTIVES: The purposes of this study were to test the hypothesis that vaginal douching is linked to bacterial vaginosis in both symptomatic and asymptomatic women and to identify other demographic, reproductive, and lifestyle factors associated with bacterial vaginosis . METHODS: In this cross-sectional study involving 3 clinic sites, 496 nonpregnant women completed a self-administered questionnaire . Their vaginal smears were assessed and cross-validated for bacterial vaginosis . RESULTS: The prevalence of bacterial vaginosis across clinics ranged from 15% to 30% . In analyses restricted to site 1, adjusted odds ratios (ORs) for bacterial vaginosis remained significant for African American women with 13 or fewer years of education (OR = 5.5, 95% confidence interval {CI} = 2.1, 14.5), hormone use within the past 6 months (OR = 0.5, 95% CI = 0.2, 0.8), and vaginal douching within the past 2 months (OR = 2.9, 95% CI = 1.5, 5.6) . CONCLUSIONS: Two lifestyle factors emerge as strongly associated with bacterial vaginosis: systemic contraceptives appear protective, whereas douching is linked to an increase in prevalence . The temporal relationship between douching and bacterial vaginosis needs further clarification. Matern Child Health J, 2001 Jun, 5(2), 127 - 34 Maternal stress is associated with bacterial vaginosis in human pregnancy; Culhane JF et al.; OBJECTIVES: Maternal infection, particularly bacterial vaginosis (BV) in pregnancy, is one of the leading causes of adverse perinatal outcomes . The determinants of individual differences in susceptibility, or vulnerability, to maternal infections are poorly understood . This study examines whether chronic maternal stress predisposes women to infection during pregnancy, and if so, whether the effects of chronic stress on infection are independent of other established risk factors . METHODS: We conducted a cross-sectional, clinical prevalence study of chronic maternal stress and BV status in a sample of 454 pregnant women at 14.3+/-0.3 weeks gestation (+/-SEM) . BV was diagnosed by Gram-stain of vaginal fluid samples; chronic maternal stress was assessed using the Cohen Perceived Stress Scale . Other established risk factors for BV, including maternal age, race/ethnicity, marital status, SES, and behaviors related to feminine hygiene, sexual practices, and substance use, were measured using a structured interview . RESULTS: Of the 454 women enrolled in this study, 224 (49%) were BV positive (Nugent score 7-10), 64 (14%) had intermediate vaginal flora (Nugent score 4-6), and 166 (37%) were BV negative (Nugent score 0-3) . BV+ women had significantly higher chronic stress levels than BV- women (24.6+/-0.5 vs . 22.2+/-0.6 units (+/-SEM), respectively; t = 3.19; p < .01) . Maternal sociodemographic variables (African-American race/ethnicity) and behavioral characteristics (vaginal douching, number of lifetime sexual partners, and use of illicit drugs) also were significantly associated with the presence of BV . After controlling for the effects of these variables, using a multivariable logistic regression model, chronic maternal stress remained a significant and independent predictor of BV status . Women in the moderate-stress group (third quartile) and high-stress (fourth quartile) group were 2.3 times (95% CI = 1.2-4.3) and 2.2 times (95% CI = 1.1-4.2) more likely to be BV+ than women in the low-stress group (bottom quartile) . CONCLUSIONS: High levels of chronic stress during pregnancy are associated with bacterial vaginosis . The effect of chronic maternal stress is independent of the effects of other established sociodemographic and behavioral risk factors for BV. Microbiol Res, 2001, 156(2), 159 - 68 Screening for trbB- and traG-like sequences by PCR for the detection of conjugative plasmids in bacterial soil isolates; Disque-Kochem C et al.; The transfer regions of different conjugative plasmids show significant similarities in the genetic organization and in the amino acid sequence of some gene products, especially of proteins from the traG or trbB family . These similarities are also evident on the level of the nucleotide sequences . On the basis of conserved DNA regions we designed degenerate PCR primer pairs to detect specifically tra regions within a collection of bacterial clones isolated from an agricultural soil . Most of the potential transfer-proficient indigenous bacterial isolates were able to mobilize a derivative of the nonconjugative IncQ plasmid RSF1010 into recipient strains . With the help of the primers it should be possible to evaluate the genetic potential for horizontal gene transfer carried out by conjugative plasmids. Microbiol Res, 2001, 156(2), 121 - 31 Physiological and genetic characteristics of two bacterial strains utilizing phenoxypropionate and phenoxyacetate herbicides; Muller RH et al.; Two strains, Rhodoferax sp . P230 and Delftia (Comamonas) acidovorans MCI, have previously been shown to carry activities for the degradation of the two enantiomers of (RS)-2-(2,4-dichlorophenoxy-)propionate (dichlorprop) and (RS)-2-(4-chloro-2-methylphenoxy-)propionate (mecoprop) and, in addition, are capable of degrading phenoxyacetate derivatives 2.4-dichlorophenoxyacetate (2,4-D) and 4-chloro-2-methylphenoxyacetate (MCPA) . Metabolism of the herbicides is initiated by alpha-ketoglutarate-dependent dioxygenases for both enantiomers of the phenoxypropionate herbicides and for 2,4-D . These activities were constitutively expressed for both enantiomers of dichlorprop in strain MC1 and for the Renantiomer in strain P230 . Enzyme activities for the complete degradation of phenoxyacetate and phenoxypropionate herbicides were induced during incubation on either of these herbicides . Strain MC1 has about threefold higher activities for the degradation of dichlorprop and for growth on this substrate (mumax = 0.15 h(-1)) than strain P230; the maximum growth rate on 2,4-D amounts to 0.045 h(-1) with strain MC1 . Dichlorprop is utilized faster than mecoprop and the R-enantiomers are cleaved with higher rates than the S-enantiomers . The degradation of the chlorophenolic intermediates seems to proceed via the modified ortho cleavage pathway as indicated by activities of the respective enzymes . The enzymatic results were supported by genetic investigations by which the presence of the genes tfdB (encoding a dichlorophenol hydroxylase), tfdC (encoding a chlorocatechol 1,2-dioxygenase) and tfdD (encoding a chloromuconate cycloisomerase) could be demonstrated in both strains by PCR after application of respective primers . The presence of the tfdA gene (encoding a 2,4-D/alpha-ketoglutarate dioxygenase) was only shown for strain P230 but was lacking in strain MC1 . Sequence analysis of the tfd gene fragments revealed high homology to the degradative genes of other proteobacterial strains degrading chloroaromatic compounds . Strain MC1 carries a plasmid of about 120 kb which apparently harbors herbicide degradative genes as concluded from deletion mutants which have lost 2,4-D{phenoxalkanoate}/alpha-ketoglutarate dioxygenase activities for cleavage of the R- and S-enantiomer, and of 2,4-D . For strain P230, no plasmid could be demonstrated; the activity was stably conserved in this strain during growth under nonselective conditions. Bone Marrow Transplant, 2001 Aug, 28(4), 413 - 5 Successful unrelated BMT in a patient with Kostmann syndrome complicated by pre-transplant pulmonary 'bacterial' abscesses; Toyoda H et al.; Kostmann syndrome, severe congenital neutropenia, is often associated with life-threatening bacterial infections . A 5-year-old girl with Kostmann syndrome developed pulmonary abscesses . She was refractory to granulocyte colony-stimulating factor and antibiotics . She underwent unrelated HLA-matched BMT . Myeloablative conditioning consisted of 12-Gy TBI with lung shielding, antithymocyte globulin, etoposide, and cyclophosphamide . After successful engraftment, the pulmonary abscesses resolved by day 75 post-transplant . Although the option of transplantation is not established in the setting of unrelated HLA-matched BMT in Kostmann syndrome, this case may provide useful information . Furthermore, pre-transplant pulmonary bacterial abscesses may not be a contraindication for BMT in some patients with Kostmann syndrome. Appl Environ Microbiol, 2001 Oct, 67(10), 4896 - 900 Assessing the diversity of marine bacterial beta-glucosidases by capillary electrophoresis zymography; Arrieta JM et al.; We propose a new method for the fast separation and detection of beta-glucosidases in environmental samples . With this approach, beta-glucosidases extracted from bacteria are evidenced by substrate-incorporated capillary electrophoresis (CE zymography) and their kinetic parameters can be determined by repeated injections using different substrate concentrations . Preliminary results obtained with natural bacterial communities from the coastal North Sea suggest that the diversity of beta-glucosidases in the marine environment might be much higher than previously observed. Appl Environ Microbiol, 2001 Oct, 67(10), 4531 - 7 Evidence for the biosynthesis of bryostatins by the bacterial symbiont "Candidatus Endobugula sertula" of the bryozoan Bugula neritina; Davidson SK et al.; The marine bryozoan, Bugula neritina, is the source of the bryostatins, a family of macrocyclic lactones with anticancer activity . Bryostatins have long been suspected to be bacterial products . B . neritina harbors the uncultivated gamma proteobacterial symbiont "Candidatus Endobugula sertula." In this work several lines of evidence are presented that show that the symbiont is the most likely source of bryostatins . Bryostatins are complex polyketides similar to bacterial secondary metabolites synthesized by modular type I polyketide synthases (PKS-I) . PKS-I gene fragments were cloned from DNA extracted from the B . neritina-"E . sertula" association, and then primers specific to one of these clones, KSa, were shown to amplify the KSa gene specifically and universally from total B . neritina DNA . In addition, a KSa RNA probe was shown to bind specifically to the symbiotic bacteria located in the pallial sinus of the larvae of B . neritina and not to B . neritina cells or to other bacteria . Finally, B . neritina colonies grown in the laboratory were treated with antibiotics to reduce the numbers of bacterial symbionts . Decreased symbiont levels resulted in the reduction of the KSa signal as well as the bryostatin content . These data provide evidence that the symbiont E . sertula has the genetic potential to make bryostatins and is necessary in full complement for the host bryozoan to produce normal levels of bryostatins . This study demonstrates that it may be possible to clone bryostatin genes from B . neritina directly and use these to produce bryostatins in heterologous host bacteria. Arch Dis Child, 2001 Oct, 85(4), 346 - 7 Effect of bacterial filters on spirometry measurements; Kamps AW et al.; Lung function measurements with and without a disposable bacterial filter were compared in 60 children . Although statistically significant, the reduction of lung function measurements caused by using bacterial filters was small and clinically irrelevant (2-4% of predicted for forced expiratory volume in one second and vital capacity). EMBO J, 2001 Sep 17, 20(18), 5280 - 9 Bacterial senescence: protein oxidation in non-proliferating cells is dictated by the accuracy of the ribosomes; Ballesteros M et al.; We have investigated the causal factors behind the age-related oxidation of proteins during arrest of cell proliferation . A proteomic approach demonstrated that protein oxidation in non-proliferating cells is observed primarily for proteins being produced in a number of aberrant isoforms . Also, these cells exhibited a reduced translational fidelity as demonstrated by both proteomic analysis and genetic measurements of nonsense suppression . Mutants harboring hyperaccurate ribosomes exhibited a drastically attenuated protein oxidation during growth arrest . In contrast, oxidation was augmented in mutants with error-prone ribosomes . Oxidation increased concomitantly with a reduced rate of translation, indicating that the production of aberrant, and oxidized proteins, is not the result of titration of the co-translational folding machinery . The age-related accumulation of the chaperones, DnaK and GroEL, was drastically attenuated in the hyperaccurate rpsL mutant, demonstrating that the reduced translational fidelity in growth-arrested cells may also be a primary cause for the induction of the heat shock regulon . The data point to an alternative way of approaching the causal factors involved in protein oxidation in eukaryotic G(0) cells. Clin Sci (Lond), 2001 Oct, 101(4), 395 - 402 Interaction between bacterial peptides, neutrophils and goblet cells: a possible mechanism for neutrophil recruitment and goblet cell depletion in colitis; Leiper K et al.; Goblet cell depletion occurs in various forms of colitis, but its mechanism is unknown . We have investigated two linked hypotheses: (i) that bacterial peptides, such as formyl-methionyl-leucyl-phenylalanine (fMLP), interact with epithelial cells inducing the release of chemokines, including interleukin-8 (IL-8), which in turn leads to the recruitment of neutrophils which release mucin secretagogues; (ii) that fMLP acts directly on epithelial cells to cause mucus secretion . Studies were performed to measure the effects of fMLP on the synthesis and secretion of IL-8 and mucus by the goblet cell differentiated colon cancer cell lines HT29-MTX (methotrexate-conditioned HT29 colonic adenocarcinoma cell line) and LS174T, and to assess the effects of neutrophil-derived secretagogues on goblet cell secretion in these cell lines . fMLP (0.1 microM) increased the secretion of IL-8 by 105% (P<0.0001) in HT29-MTX cells and by 401% (P<0.0001) in LS174T cells . fMLP also increased the synthesis and secretion of mucins by these cell lines, with maximal effects of 65% above control values for synthesis (P<0.01) and 73% for secretion (P<0.01) . A dose-related increase (up to 67%; P<0.01) in mucin secretion was demonstrated in HT29-MTX cells in response to incubation with supernatant from activated neutrophils . This effect was largely (83%; P<0.02) inhibited by ICI 200,355, a specific inhibitor of neutrophil elastase . In conclusion, the bacterial peptide fMLP and neutrophil elastase are both potent mucus secretagogues for colon epithelial cells . fMLP also elicits release of the potent neutrophil chemoattractant IL-8 from colon epithelial cells . These findings support the hypothesis that the mucosal inflammation and mucus depletion seen in ulcerative colitis could result from interaction between bacterial peptides and the mucosa. J Biol Chem, 2001 Dec 7, 276(49), 45669 - 76 Epub 2001 Sep 19. Sensitivity of different ecotypes and mutants of Arabidopsis thaliana toward the bacterial elicitor flagellin correlates with the presence of receptor-binding sites; Bauer Z et al.; Flagellin, the main building block of the bacterial flagellum, acts as potent elicitor of defense responses in different plant species . Genetic analysis in Arabidopsis thaliana identified two distinct loci, termed FLS1 and FLS2, that are essential for perception of flagellin-derived elicitors . FLS2 was found to encode a leucine-rich repeat transmembrane receptor-like kinase with similarities to Toll-like receptors involved in the innate immune system of mammals and insects . Here we used a radiolabeled derivative of flg22, a synthetic peptide representing the elicitor-active domain of flagellin, to probe the interaction of flagellin with its receptor in A . thaliana . The high affinity binding site detected in intact cells and membrane preparations exhibited specificity for flagellin-derived peptides with biological activity as agonists or antagonists of the elicitor responses . Specific binding activity was measurable in all ecotypes of A . thaliana that show sensitivity to flagellin but was barely detectable in the flagellin-insensitive ecotype Ws-0 affected in FLS1 . A strongly impaired binding of flagellin was observed also in several independent flagellin-insensitive mutants isolated from the flagellin-sensitive ecotype La-er . In particular, no binding was found in plants carrying a mutation in the LRR domain of FLS2 . These data indicate that the formation of functional receptor-binding sites depends on genes encoded by both loci, FLS1 and FLS2 . The tight correlation between the presence of the binding site and elicitor response provides strong evidence that this binding site acts as the physiological receptor of flagellin. J Protein Chem, 2001 Feb, 20(2), 139 - 44 The effect of inorganic phosphate on the activity of bacterial ribokinase; Maj MC et al.; Ribokinase and adenosine kinase are both members of the PfkB family of carbohydrate kinases . The activity of mammalian adenosine kinase was previously shown to be affected by pentavalent ions (PVI) . We now present evidence that the catalytic activity of E . coli ribokinase is also affected by PVI, increasing both the velocity and affinity of the enzyme for D-ribose . The Km, for ribose decreased from 0.61 mM to 0.21, 0.25, and 0.33 mM in the presence of 20 mM phosphate, arsenate, and vanadate, respectively . The activity of ribokinase was stimulated in a hyperbolic fashion, with the maximum velocity increasing 23-fold, 13-fold, and 11-fold under the same conditions, respectively . Activity was also affected upon the addition of phosphoenolpyruvate, suggesting that phosphorylated metabolites could be involved in enzymatic control . The similar effect of PVI on distantly related enzymes suggests that a common mechanism for activity is shared among PfkB family members. Environ Sci Technol, 2001 Sep 1, 35(17), 3442 - 7 Bacterial growth in distribution systems: effect of assimilable organic carbon and biodegradable dissolved organic carbon; Escobar IC et al.; Two distribution systems, one treating water by ozonation and another treating water by nanofiltration in parallel with lime softening, were monitored for bacterial growth . Both systems kept disinfectant residuals such as chlorine and chloramine in their respective distribution systems . Bacterial growth was assessed by heterotrophic plate counts (HPC) on R2A agar . In the distribution systems fed by ozonated water, HPCs were correlated (R2 = 0.96) using an exponential model with the assimilable organic carbon (AOC) at each sampling site . Also, it was observed that ozonation caused a significant increase in the AOC concentration of the distribution system (over 100% increase) as well as a significant increase in the bacterial counts of the distribution system (average increase over 100%) . The HPCs from the distribution systems fed by nanofiltration in parallel with lime-softening water also displayed an exponential correlation (R2 = 0.73) with an exponential model based on AOC . No significant correlation was found between bacteria growth on R2A agar and BDOC concentrations . Therefore, in agreement with previous work, bacterial growth in the distribution systems was found to correlate with AOC concentrations. Indian J Pediatr, 2001 Aug, 68(8), 737 - 47 Bacterial meningitis in children: critical care needs; Singhi S et al.; Acute bacterial meningitis (ABM) in children is associated with a high rate of acute complications and mortality, particularly in the developing countries . Most of the deaths occur during first 48 hours of hospitalization . Coma, raised intracranial pressure (ICP), seizures, shock have been identified as significant predictors of death and morbidity . This article reviews issues in critical care with reference to our experience of managing 88 children with ABM in PICU . Attention should first be directed toward basic ABCs of life-support . Children with Glasgow Coma Scale (GSC) score < 8 need intubation and supplemental oxygen . Antibiotics should be started, even without LP (contraindicated if focal neuro-deficit, papilledema, or signs of raised ICP) . Raised ICP is present in most of patients; GCS < 8 and high blood pressure are good guides . Mannitol (0.25 gm/Kg) should be used in such patients . If there are signs of (impending) herniation short-term hyperventilation is recommended; prolonged hyperventilation (> 1 hour) must be avoided . Any evidence of poor perfusion, hypovolemia and/or hypotension needs aggressive treatment with normal saline boluses and inotropes, if necessary, to maintain normal blood pressure . Empiric fluid restriction is not justified . Seizures may be controlled with intravenous diazepam or lorazepam . Refractory status epilepticus may be treated with continuous diazepam (0.01-0.06) mg/kg/min) or midazolam infusion . Ventilatory support may be needed early for associated pneumonia, poor respiratory effort and/or coma, and occasionally to reduce work of breathing in shock . Provision of critical care to children with ABM may reduce the mortality significantly as experienced by us. Nucleosides Nucleotides Nucleic Acids, 2001 Apr-Jul, 20(4-7), 977 - 9 Recombinant bacterial cells as efficient biocatalysts for the production of nucleosides; Spoldi E et al.; The preparation of nucleosides as well as their base-modified analogues using purified nucleoside phosphorylase enzymes or, more conveniently, using whole bacterial cells is described . The development of genetically modified strains of Escherichia coli, able to over-produce Uridine-phosphorylase and Purine-nucleoside-phosphorylase in the same cells, improves the specific biocatalytic activity and the consequent industrial scale approach. Mol Cells, 2001 Aug 31, 12(1), 117 - 20 Construction and characterization of a bacterial artificial chromosome library from chili pepper; Yoo EY et al.; A library of the bacterial artificial chromosome (BAC) that consisted of a total of 78,336 clones with an average insert size of 80 kb was constructed from Capsicum annuum, 'CM334', which is resistant to Phytophthora capsici and PVY . Based on a haploid genome size of pepper of 2,702 Mbp/C, the BAC library was estimated to contain approximately three genome equivalents and represented at least 90% of the pepper genome . In order to determine the percentage of BAC clones that contained mitochondrial DNAs, the entire library was screened with probes of chili pepper mitochondrial DNAs . The result showed that only twenty-five clones, which is 0.03% of the total BAC clones, were hybridized to mitochondrial gene probes . This indicates that the library is comprised predominantly of the nuclear sequences . The library was also tested for isolating specific clones by screening with a few known genes from the chili pepper, phytoene synthase gene, and two MADS genes--HpMADS1 and HpMADS3 . The result showed that the three clones for phytoene synthase and the two clones for each MADS gene were positively hybridized to the specific probes . This indicates that the library is highly reliable and represents a resource for initiating map-based cloning and contig mapping in chili pepper. Lett Appl Microbiol, 2001 Oct, 33(4), 296 - 301 A comparison of nucleic acid amplification techniques for the assessment of bacterial viability; Birch L et al.; AIMS: The ability to determine the presence and viability status of bacteria by molecular methods could offer significant advantages to the food, environmental and health sectors, in terms of improved speed and sensitivity of detection . METHODS AND RESULTS: In this study, we have assessed three amplification techniques, PCR, RT-PCR and NASBA, for their ability to detect nucleic acid persistence in an E . coli strain following heat-killing . NASBA offered the greatest sensitivity of the three methods tested . The presence of residual DNA and mRNA could be detected by PCR and NASBA, respectively, for up to 30 h postdeath, by which time cell death had been confirmed by culture methods . Thus a single quantitative measurement based on nucleic acid amplification did not permit unequivocal determination of cell viability . CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: The correlation between cell viability and persistence of nucleic acids must be well characterized for a particular analytical situation before molecular techniques can be substituted for traditional culture methods. Antimicrob Agents Chemother, 2001 Oct, 45(10), 2936 - 8 Comparison of once-daily versus twice-daily administration of cefdinir against typical bacterial respiratory tract pathogens; Ross GH et al.; In an in vitro pharmacodynamic model, a twice-daily cefdinir dosing regimen was more effective than a once-daily regimen against common bacterial respiratory pathogens in producing 3-log(10) killing and preventing the occurrence of regrowth at 24 h . Twice-daily administration is likely the more appropriate cefdinir dosing strategy for the treatment of community-acquired pneumonia. Eur J Intern Med, 2001 Sep, 12(5), 454 - 458 Non-bacterial thrombotic (marantic) endocarditis associated with giant-cell arteritis; Hesselink DA et al.; A patient with giant-cell arteritis and non-bacterial thrombotic (marantic) endocarditis of the mitral valve is described . To our knowledge, this is the first case reported . The importance of revising the diagnosis of infective endocarditis when no pathogen can be demonstrated is emphasized. Brain Pathol, 2001 Oct, 11(4), 422 - 31 Expression of death-related proteins in dentate granule cells in human bacterial meningitis; Gerber J et al.; Neuronal apoptosis in the dentate gyrus has been observed in animal models of bacterial meningitis and in humans dying in the course of the disease.To evaluate the mechanisms of neuronal cell death, hippocampal sections of 20 patients dying from bacterial meningitis were investigated by immunohistochemistry using antibodies against the proform of caspase-3 and the active enzyme, bcl-2, bax and p53 . In the dentate granule cell layer, the median density of neurons with an apoptotic morphology was 7.6/mm2 (0-15.6/mm2) . The median density of immunoreactive neurons was 2.3/mm2 (procaspase-3), 0.9/mm2 (activated caspase-3), 1.8/mm2 (bcl-2), 1.1/mm2 (bax) and 0.4/mm2 (p53) . 80% of neurons immunoreactive for active caspase-3 had an apoptotic morphology, whereas only 10% of all procaspase-3 stained neurons showed signs of apoptosis . Apoptotic cell death is present in humans dying in the course of bacterial meningitis in the dentate gyrus of the Formatio hippocampi . Neuronal expression of caspase-3, bcl-2 and bax suggests an involvement of these proteins in neuronal death. Int J Med Microbiol, 2001 Aug, 291(3), 197 - 207 Modification of host cell apoptosis by viral and bacterial pathogens; Muller A et al.; Bacterial and viral pathogens have evolved sophisticated strategies to manipulate the host cell's life span to their own advantage . This is achieved by modifications of the intrinsic apoptosis program at several checkpoints: kinases, caspases and mitochondria . The goal of this review is to give an overview over the molecular mechanisms involved. Clin Orthod Res, 2001 May, 4(2), 112 - 8 Bacterial degradation of composite bonding materials; Donker HJ et al.; The causes of bracket loss during the late phases of orthodontic treatment have hitherto been considered to be of mechanical nature (e.g . trauma, high forces applied) . Recently, it was hypothesized that bacterial degradation of composite resin could be a reason for late bracket failure . This was based on the observation of apparently degraded composite on bracket bases sent to a recycling company, and on a weight loss of 0.1-1% of a limited number of composite resin foils incubated with bacteria . To further elucidate the basis for this hypothesis, we examined brackets, immediately after debonding, for signs of potential decay and tested the ability of selected bacterial species to degrade composites . Out of a total of 1056 brackets collected, 6.2% displayed signs of decay indicative of inclusion of air bubbles, corrosion of the bracket base and discoloration of the composite and comparable to the decay observed on brackets received from the recycling company . Composite discs of two different brands were each incubated with either of five strains representing different bacterial species . The incubation lasted 3 months or until the bacteria had died . There was no significant difference in weight change of the discs incubated with bacteria and control discs incubated without bacteria . Thus, our results do not support that bacterial degradation of composite resin bonding materials is a likely cause of bracket loss. Rev Med Chil, 2001 Jul, 129(7), 719 - 26 {Trends of etiology of acute bacterial meningitis in Chilean children from 1989 to 1998 . Impact of the anti-H influenzae type b vaccine}; Diaz JM et al.; BACKGROUND: Acute bacterial meningitis still has a high mortality and rate of complications . AIM: To assess the impact of anti H influenzae vaccination on the epidemiology of acute bacterial meningitis in Chilean children . MATERIAL AND METHODS: A retrospective study of hospital discharge records of patients with acute bacterial meningitis . Causative agents were studied globally, by hospital and by age group . The changes in etiology from 1989 to 1995 were also assessed . Between 1996 and 1998, only those patients with acute bacterial meningitis caused by H influenzae were recollected . RESULTS: In the period prior to vaccination (1989-1995), 1000 cases were registered . The main causative agents were N meningitidis in 33.8%, H influenzae type b in 21.9% and S pneumoniae in 15.4% . The incidence of H influenzae decreased in the period from 36.4 to 9.9% (p < 0.001) and the incidence of N meningitidis increased from 22.9 to 52.1% (p < 0.001) . The incidence of S pneumoniae did not change significantly . H influenzae predominated in children between 4 and 24 months of age and N meningitidis predominated in children over 25 months of age . In the period after the introduction of vaccination (1995-1998), there was a further decrease in the incidence of H influenzae from 10 to 2% (p < 0.001) . Until 1997, there was a considerable increase in the incidence of N meningitidis, specially in children over 25 months of age . It declined in 1998 to 38% . CONCLUSIONS: There was a reduction in the incidence of acute bacterial meningitis caused by H influenzae prior to the introduction of the vaccine against H influenzae type b . The decrease was more pronounced after the introduction of the vaccine. J Struct Biol, 2001 May-Jun, 134(2-3), 219 - 31 Fold predictions for bacterial genomes; Pawlowski K et al.; Fold assignments for newly sequenced genomes belong to the most important and interesting applications of the booming field of protein structure prediction . We present a brief survey and a discussion of such assignments completed to date, using as an example several fold assignment projects for proteins from the Escherichia coli genome . This review focuses on steps that are necessary to go beyond the simple assignment projects and into the development of tools extending our understanding of functions of proteins in newly sequenced genomes . This paper also discusses several problems seldom addressed in the literature, such as the problem of domain prediction and complementary predictions (e.g., transmembrane regions and flexible regions) and cross-correlation of predictions from different servers . The influence of sequence and structure database growth on prediction success is also addressed . Finally, we discuss the perspectives of the field in the context of massive sequence and structure determination projects, as well as the development of novel prediction methods . Zh Mikrobiol Epidemiol Immunobiol, 2001 May-Jun, (3), 46 - 9 {Immunoprophylaxis of acute respiratory diseases with bacterial multicomponent vaccine VP-4 in children at preschool institutions}; Egorova NB et al.; The prophylactic action of polycomponent vaccine B{symbol: see text}-4, prepared from the antigens of opportunistic bacteria, on morbidity rate in acute respiratory diseases (ARD) of bacterial and mixed (bacterial and viral) etiology in 121 children aged 2-5 years, attending pre-school institutions was evaluated . For comparison, a group of 118 children of the same age from the same institutions was formed . The vaccine was introduced after the schedule consisting of 3 intranasal and 6-9 oral administrations made at intervals of 3-4 days . The duration of the course of immunization was 26 +/- 4 days . The prophylactic effect of B{symbol: see text}-4 on ARD morbidity was evaluated by the number of ARD cases and their duration per child . The prophylactic effect of B{symbol: see text}-4 on ARD morbidity lasted 14 months (the term of observation) after immunization and was manifested by a decrease in the number and duration of ARD cases after administration of the preparation, also in a group of highly susceptible children. Water Res, 2001 Oct, 35(14), 3490 - 5 Use of bacterial biosensors to interpret the toxicity and mixture toxicity of herbicides in freshwater; Strachan G et al.; The dose response relationship between seven commonly used herbicides and four luminescence-based bacterial biosensors was characterised . As herbicide concentration increased the light emitted by the test organism declined in a concentration dependent manner . These dose responses were used to compare the predicted vs . observed response of a biosensor in the presence of multiple contaminants . For the majority of herbicide interactions, the relationship was not additive but primarily antagonistic and sometimes synergistic . These biosensors provide a sensitive test and are able to screen a large volume and wide range of samples with relative rapidity and ease of interpretation . In this study biosensor technology has been successfully applied to interpret the interactive effects of herbicides in freshwater environments. Infection, 2001 Aug, 29(4), 209 - 12 Predictive value of serum and cerebrospinal fluid procalcitonin levels for the diagnosis of bacterial meningitis; Jereb M et al.; BACKGROUND: The value of serum and cerebrospinaL fluid (CSF) procalcitonin for differentiating between acute bacterial and viral meningitis was assessed and compared to other parameters which are usually used in clinical practice . PATIENTS: 45 adult patients (20 with bacterial and 25 with tick-borne encephalitis, TBE) were included in this prospective study . RESULTS: The median serum procalcitonin Level in patients with bacterial meningitis was 6.45 ng/ml (range 0.25-43.76 ng/ml) and in the group with viral meningitis 0.27 ng/ml (range 0.05-0.44 ng/ml) . 11 patients with bacterial meningitis had an elevated procalcitonin concentration not only in serum, but also in CSF . A serum procalcitonin Level > 0.5 ng/ml had a positive predictive value for bacterial meningitis of 100% and a negative predictive value of 93%, while corresponding values for CSF procalcitonin were 100% and 74%, respectively . CONCLUSION: Serum and CSF procalcitonin concentrations > 0.5 ng/ml appear to be a reliable indicator of bacterial central nervous system (CNS) infection, with maximal positive predictive values and high negative predictive values. J Mol Microbiol Biotechnol, 2001 Oct, 3(4), 557 - 62 Development of a bacterial screen for novel hypoxanthine-guanine phosphoribosyltransferase substrates; Shivashankar K et al.; The lack of de novo purine biosynthesis in many parasitic protozoans makes the enzymes in the salvage of purines attractive chemotherapeutic targets . Hypoxanthine-guanine phosphoribosyltransferase (HGPRT) is a key enzyme for purine salvage and bacterial complementation screens for HGPRT inhibitors are known . The low KMS for purine bases makes purine analogs unattractive as competitive inhibitors for this enzyme . Despite the availability of many crystal structures of HGPRTs, it is only recently that selective inhibitors of the enzyme have been developed . Therefore, novel purine analogs which act as substrates for the HGPRT reaction and thereby inhibit downstream enzymes or get incorporated into the nucleotide pool are an attractive altenative for drug design . We have used a combination of two E . coli strains Sphi606 (ara, deltapro-gpt-lac, thi, hpt) and Sphi609 (ara, deltapro-gpt-lac, thi, hpt, pup, purH,J, strA) to identify inhibitors and substrates of HGPRT . E . coli Sphi609 is deficient in both de novo synthesis as well as salvage enzymes of purine nucleotide synthesis, while E . coli Sphi606 is deficient in salvage enzymes only . Hence, expression of functional HGPRTs in E . coli Sphi606 grown in minimal medium makes it susceptible to HGPRT substrates, which inhibit downstream processes . Growth of E . coli Sphi609 in minimal medium can be made conditional for the expression of a functional HGPRT and this growth would be susceptible to both HGPRT substrate analogs and inhibitors . A substance that strictly acts as an inhibitor will affect growth of transformed E . coli Sphi609 only . For this purpose, we compared the human and P . falciparum enzymes with known HGPRT substrate analogs . Our data with 6-mercaptopurine, 6-thioguanine and allopurinol show that these compounds act by being substrates for HGPRT . Our results with allopurinol suggest that it is a better substrate for P . falciparum HGXPRT than the human enzyme . Therefore, species-specific substrates can be tested out successfully in E . coli Sphi606 . The formation of products from substrates like allopurinol lacking a labile proton at N7 raises the possibility that the deprotonation of substrates might occur at N9 rather than at N7 or a purine anion might be the true substrate for the reaction. Annu Rev Microbiol, 2001, 55, 407 - 35 Interaction of bacterial pathogens with polarized epithelium; Kazmierczak BI et al.; Many pathogens must surmount an epithelial cell barrier in order to establish an infection . While much has been learned about the interaction of bacterial pathogens with cultured epithelial cells, the influence of cell polarity on these events has only recently been appreciated . This review outlines bacterial-host epithelial cell interactions in the context of the distinct apical and basolateral surfaces of the polarized epithelium that lines the lumens of our organs. J Bacteriol, 2001 Oct, 183(19), 5506 - 12 Autophosphorylation of a bacterial serine/threonine kinase, AfsK, is inhibited by KbpA, an AfsK-binding protein; Umeyama T et al.; A protein serine/threonine kinase, AfsK, and its target protein AfsR globally control physiological and morphological differentiation in the bacterial genus Streptomyces . A protein (KbpA) of 252 amino acids encoded by an open reading frame in a region upstream of afsK in Streptomyces coelicolor A3(2) was identified as an AfsK-interacting protein . The interaction site of AfsK was in the N-terminal portion containing the kinase catalytic domain . KbpA bound a nonphosphorylated form of AfsK and inhibited its autophosphorylation at serine and threonine residues . KbpA in the reaction mixture containing AfsK and AfsR also inhibited the phosphorylation of AfsR by AfsK, presumably because KbpA inhibited the conversion from the inactive, nonphosphorylated form of AfsK to the active, phosphorylated form . kbpA was transcribed throughout growth, and the transcription was enhanced when production of actinorhodin had already started . KbpA thus appeared to play an inhibitory role in a negative feedback system in the AfsK-AfsR regulatory pathway . Consistent with these in vitro observations, kbpA served as a repressor for actinorhodin production in S . coelicolor A3(2); disruption of kbpA greatly enhanced actinorhodin production, and overexpression of kbpA reduced the production. Comp Biochem Physiol C Toxicol Pharmacol, 2001 Sep, 130(1), 107 - 17 Eicosanoids act in nodulation reactions to bacterial infections in newly emerged adult honey bees, Apis mellifera, but not in older foragers; Bedick JC et al.; Nodulation is the first, and qualitatively predominant, cellular defense reaction to bacterial infections in insects . We tested the hypothesis that eicosanoids also mediate nodulation reactions to bacterial challenge in adults of a social insect, the honey bee, Apis mellifera . Treating newly-emerged experimental bees with the eicosanoid biosynthesis inhibitor, dexamethasone, impaired nodulation reactions to bacterial infections, and the influence of dexamethasone was reversed by treating infected insects with arachidonic acid, an eicosanoid precursor . Several other eicosanoid biosynthesis inhibitors, including the cyclooxygenase inhibitor, indomethacin, and the dual cyclooxygenase/lipoxygenase inhibitor, phenidone, also impaired the ability of experimental honeybees to form nodules in reaction to bacterial challenge . The influence of phenidone on nodulation was expressed in a dose-dependent manner . However, in experiments with older honey bees foragers, similar bacterial challenge did not evoke nodulation reactions . We infer from our results that while eicosanoids mediate cellular immune responses to bacterial infections in newly emerged honey bees, and more broadly, in most insect species, nodulation reactions to bacterial challenge probably do not occur in all phases of insect life cycles. Microgravity Sci Technol, 1999, 12(2), 74 - 7 Effects of space flight and mixing on bacterial growth in low volume cultures; Kacena MA et al.; Previous investigations have shown that liquid suspension bacterial cultures grow to higher cell concentrations in spaceflight than on Earth . None of these studies included ground-control experiments designed to evaluate the fluid effects potentially responsible for the reported increases . Therefore, the emphasis of this research was to both confirm differences in final cell concentration between 1g and microgravity cultures, and to examine the effects of mixing as a partial explanation for this difference . Flight experiments were performed in the Fluid Processing Apparatus (FPA), aboard Space Shuttle Missions STS-63 and STS-69, with simultaneous 1g static and agitated controls . Additional static 1g, agitated, and clino-rotated controls were performed in 9-ml culture tubes . This research revealed that both E . coli and B . subtilis samples cultured in space flight grew to higher final cell densities (120-345% increase) than simultaneous static 1g controls . The final cell concentration of E . coli cells cultured under agitation was 43% higher than in static 1g cultures and was 102% higher with clino-rotation . However, for B . subtilis cultures grown while being agitated on a shaker or clino-rotated, the final cell concentrations were nearly identical to those of the simultaneous static 1g controls . Therefore, these data suggest that the unique fluid quiescence in the microgravity environment (lack of sedimentation, creating unique transfer of nutrients and waste products), was responsible for the enhanced bacterial proliferation reported in this and other studies. Adv Space Res, 1983, 3(8), 95 - 104 Effect of heavy ions on bacterial spores; Takahashi T et al.; Inactivation of B . subtilis spores has been studied using accelerated He, C, N, O and Ne ions . The energy dependence of the inactivation cross sections for heavy ions was very weak and the mean cross sections for carbon ions (0.6-4.7 MeV/amu), nitrogen ions (0.6-4.1 MeV/amu), oxygen ions (0.8-1.1 MeV/amu), and neon ions (2.2-3.7 MeV/amu) were found to be about 0.22, 0.23, 0.26, and 0.33 micrometer2 , respectively . Analysis was carried out along lines similar to Katz's target theory but the parameters were chosen so that they have an experimental basis. Adv Space Res, 1983, 3(8), 73 - 8 Physical determinants of radiation sensitivity in bacterial spores; Powers EL; Several factors modifying radiation sensitivity in dry bacterial spores are described and discussed . Vacuum inducing the loss of critical structural water, very low dose rates of radiation from which the cell may recover, radiations of high linear energy transfer, and the action of temperature over long periods of time on previously irradiated cells are recognized from extensive laboratory work as important in determining survival of spores exposed to low radiation doses at low temperatures for long periods of time . Some extensions of laboratory work are proposed. Adv Space Res, 1983, 3(8), 105 - 12 Oxygen effect, hydrogen peroxide yields, and time scale of interaction of potentially damaging species in electron pulse irradiated bacterial spores; Tallentire A; A given integrated radiation dose delivered from a LINAC as a train of pulses (50/s), characteristically of 0.1 to 5 microseconds pulse length with dose rates within the pulse between 0.38 and 38 krads/microsecond, inactivates bacterial spores in water suspension more effectively than the same dose given as Co60 gamma rays . This enhancement of radiation damage occurs both in the presence and in the absence of oxygen and is not explained by either pulse dose rate or pulse length alone, but is monotonically related to the product of these pulse parameters, pulse dose . The enhancement appears to result from the interaction, within individual spores, of free radical species of average lifetime of about 2-5 microseconds . The time scale over which these species operate suggests that they are freely diffusable . Prevention, in part, of their damaging effect by the presence of selective scavenging agents is evidence that OH radicals are involved . Measurements of H2O2 yield for irradiation conditions that show a gradation of enhancement of damage correlate strongly with the extent of damage observed. Science, 1994 Dec 23, 266, 1973 - 5 The production of 34S-depleted sulfide during bacterial disproportionation of elemental sulfur; Canfield DE et al.; Bacteria that disproportionate elemental sulfur fractionate sulfur isotopes such that sulfate is enriched in sulfur-34 by 12.6 to 15.3 per mil and sulfide is depleted in sulfur-34 by 7.3 to 8.6 per mil . Through a repeated cycle of sulfide oxidation to S0 and subsequent disproportionation, these bacteria can deplete sedimentary sulfides in sulfur-34 . A prediction, borne out by observation, is that more extensive sulfide oxidation will lead to sulfides that are more depleted in sulfur-34 . Thus, the oxidative part of the sulfur cycle creates circumstances by which sulfides become more depleted in sulfur-34 than would be possible with sulfate-reducing bacteria alone. Genome Biol . 2000;1(6):REVIEWS0006 . Epub 2000 Dec 08. Evaluating genome dynamics: the constraints on rearrangements within bacterial genomes; Hughes D; Inversions and translocations distinguish the genomes of closely related bacterial species, but most of these rearrangements preserve the relationship between the rearranged fragments and the axis of chromosome replication . Within species, such rearrangements are found less frequently, except in the case of clinical isolates of human pathogens, where rearrangements are very frequent. FEBS Lett, 2001 Aug 31, 504(3), 104 - 11 Carbohydrate transporters of the bacterial phosphoenolpyruvate: sugar phosphotransferase system (PTS); Siebold C et al.; The glucose transporter of Escherichia coli couples translocation with phosphorylation of glucose . The IICB(Glc) subunit spans the membrane eight times . Split, circularly permuted and cyclized forms of IICB(Glc) are described . The split variant was 30 times more active when the two proteins were encoded by a dicistronic mRNA than by two genes . The stability and activity of circularly permuted forms was improved when they were expressed as fusion proteins with alkaline phosphatase . Cyclized IICB(Glc) and IIA(Glc) were produced in vivo by RecA intein-mediated trans-splicing . Purified, cyclized IIA(Glc) and IICB(Glc) had 100% and 30% of wild-type glucose phosphotransferase activity, respectively . Cyclized IIA(Glc) displayed increased stability against temperature and GuHCl-induced unfolding. Mol Microbiol, 2001 Aug, 41(3), 645 - 52 Ectopic transposition of a group II intron in natural bacterial populations; Munoz E et al.; Self-splicing group II introns are thought to be the evolutionary progenitors of eukaryotic spliceosomal introns . The invasion of novel (ectopic) sites by group II introns is considered to be a key mechanism by which spliceosomal introns may have become widely dispersed . However, the dynamics of these events in populations are unknown . In bacteria, only two group II introns have been shown to splice and to be mobile in vivo . One of these introns, RmInt1 from Sinorhizobium meliloti, which encodes a protein with no endonuclease domain, has been shown to invade the ectopic oxi1 site independently of recombinase . In this study, we analysed ectopic transposition of the RmInt1 intron in a natural population of S . meliloti . We characterized S . meliloti isolates by polymerase chain reaction amplification of a gene, dapB, which is found only on the pRmeGR4b plasmid diagnostic of GR4-type strains . The diversity within this specific field population of bacteria was analysed by restriction fragment length polymorphism using ISRm2011-2 (homing site of RmInt1) and RmInt1 as probes . We found that ectopic transposition of RmInt1 to the oxi1 site occurred in this natural bacterial population . This ectopic transposition was also the most frequent genetic event observed . This work provides further evidence that the ectopic transposition of group II introns is an important mechanism for their spread in natural bacterial populations. Eur J Biochem, 2001 Sep, 268(17), 4794 - 801 Bacterial expression and conformational analysis of a chemosensory protein from Schistocerca gregaria; Picone D et al.; Chemosensory proteins (CSPs) are a class of small, soluble proteins present at high concentrations in chemosensory organs of different insect species . Several pieces of evidence suggest their involvement in carrying chemical messages from the environment to chemosensory receptors . However, a structural description of the mechanism of delivery has not been reported . In order to provide the first detailed conformational characterization of these molecules, we cloned a specific isoform (CSP-sg4) from Schistocerca gregaria and expressed it in Escherichia coli . The product was obtained with yields of more than 20 mg per L of culture, all in its soluble form . The recombinant protein was identical to the native one with respect to pairing of the disulfide bridges, aggregative state and secondary structure elements . Structural investigations revealed a significantly stable polypeptide with respect to variations in temperature and acidity . CD analysis, preliminary NMR data and secondary structure prediction pointed to a correctly folded structure where helical regions and loops are alternated in a similar fashion as that observed for other classes of odorant- and pheromone-binding proteins presenting no sequence similarity to CSPs. Shock, 2001 Sep, 16(3), 183 - 8 PGE2 suppresses intestinal T cell function in thermal injury: a cause of enhanced bacterial translocation; Choudhry MA et al.; Increased gut bacterial translocation in burn and trauma patients has been demonstrated in a number of previous studies, however, the mechanism for such an increased gut bacterial translocation in injured patients remains poorly understood . Utilizing a rat model of burn injury, in the present study we examined the role of intestinal immune defense by analyzing the T cell functions . We investigated if intestinal T cells dysfunction contributes to bacterial translocation after burn injury . Also our study determined if burn-mediated alterations in intestinal T cell functions are related to enhanced release of PGE2 . Finally, we examined whether or not burn-related alterations in intestinal T cell function are due to inappropriate activation of signaling molecule P59fyn, which is required for T cell activation and proliferation . The results presented here showed an increase in gut bacterial accumulation in mesenteric lymph nodes after thermal injury . This was accompanied by a decrease in the intestinal T cell proliferative responses . Furthermore, the treatments of burn-injured animals with PGE2 synthesis blocker (indomethacin or NS398) prevented both the decrease in intestinal T cell proliferation and enhanced bacterial translocation . Finally, our data suggested that the inhibition of intestinal T cell proliferation could result via PGE2-mediated down-regulation of the T cell activation-signaling molecule P59fyn . These findings support a role of T cell-mediated immune defense against bacterial translocation in burn injury. Klin Lab Diagn, 2001 Jul, (7), 15 - 9 {Diagnostic significance of the cerebrospinal fluid protein spectrum in bacterial and viral meningitis in children}; Alekseeva LA et al.; Protein spectrum of the cerebrospinal fluid (CSF) was studied by polyacrylamide gel disk electrophoresis in 119 children with bacterial and 17 with viral meningitis of different origin over the course of disease . Liquor proteinograms of patients were compared with those of 37 children without meningitis . Protein spectra of the CSF were shifted in the patients . These shifts can serve as differential diagnostic markers: types 1-2 and 2-2 haptoglobins and beta-lipoprotein appears in the blood during the acute period of disease . More pronounced and stubborn changes in the CSF protein spectrum in pneumococcal and hemophilic meningitis correlated with a more severe clinical course and formation of residual neurological consequences . Progress of dysproteinemic shifts in the protein spectrum of the CSF was characterized by a many-fold increase in the concentrations of high-molecular-weight proteins and decreased relative content of liquor-specific fractions, indicating sharp impairment of the blood-brain barrier permeability and formation of brain edema . Disk electrophoresis method is characterized by high resolution, informative value, requires low amounts of CSF for analysis, and is recommended as an accessory diagnostic test for infectious hospitals. Obstet Gynecol, 2001 Sep, 98(3), 476 - 80 Interleukin-10 administration and bacterial endotoxin-induced preterm birth in a rat model; Terrone DA et al.; OBJECTIVE: To determine whether intra-uterine infusion of interleukin-10 prevents preterm delivery in rats treated with endotoxin . METHODS: Pregnant rats underwent implantation of uterine catheters and were randomly assigned to receive intrauterine infusion of either normal saline, 50 microg lipopolysaccharide endotoxin, or 50 microg lipopolysaccharide with 500 ng interleukin-10 administered either concurrently or 24 hours later . The interval from infusion to delivery for each group was recorded, along with the number of live born pups and their birth weight . We calculated that to obtain a power of 80%, assuming a 24-hour difference in the treatment to delivery times between the test and control subjects, at least six animals would be needed in each group . RESULTS: In females receiving lipopolysaccharide (50 microg) alone, the interval to delivery (P <.05), live birth rate (P <.05), and pup weight (P <.001) were reduced compared with the saline-infused controls . In contrast, females receiving interleukin-10 at the time of the endotoxin challenge or 24 hours after delivered at term with no difference in litter size or live birth weight compared with the controls . CONCLUSION: Animals treated with both lipopolysaccharide and interleukin-10, administered concurrently or 24 hours after the endotoxin challenge, delivered normal weight pups at term with a similar litter size as the saline-infused controls . Interleukin-10 appears to be effective in preventing endotoxin-induced preterm birth and fetal wastage in pregnant rats. Clin Infect Dis, 2001 Oct 1, 33(7), 1022 - 7 Epub 2001 Sep 05. Gardnerella vaginalis isolated from patients with bacterial vaginosis and from patients with healthy vaginal ecosystems; Aroutcheva AA et al.; The differences in the phenotype and genotype of Gardnerella vaginalis isolates from patients with bacterial vaginosis (BV) and from patients without BV are unknown . In our study, 43 isolates of G . vaginalis were examined for biotype (hippurate hydrolysis, lipase, and beta-galactosidase activity), sensitivity to metronidazole, and genotype . Of the 117 women visiting the gynecology clinic at Rush-Presbyterian-St . Luke's Medical Center who were included in the study, 27.4% were found to have BV . G . vaginalis was found in samples from 87.5% of women with BV, from 34.0% of women with intermediate BV, and from 26.4% of women with healthy vaginal ecosystems . Among patients with G . vaginalis, biotypes 7 and 8 were isolated from 32% and 20% of patients, respectively . Biotype 5 was predominantly associated with a healthy vaginal ecosystem (P=.0004) . Biotypes 5 and 7 were the most resistant to metronidazole . No specific phenotype or genotype of G . vaginalis causes BV. Clin Infect Dis, 2001 Oct 1, 33(7), 969 - 75 Epub 2001 Aug 22. Community-acquired bacterial meningitis in adults: categorization of causes and timing of death; McMillan DA et al.; The relationship between cause and timing of death in 294 adults who had been hospitalized with community-acquired bacterial meningitis was investigated . For 74 patients with community-acquired bacterial meningitis who died during hospitalization, the underlying and immediate causes of death were identified according to the criteria of the World Health Organization and National Center for Health Statistics . Patients were classified into 3 groups: category I, in which meningitis was the underlying and immediate cause of death (59% of patients; median duration of survival, 5 days); category II, in which meningitis was the underlying but not immediate cause of death (18%; median duration of survival, 10 days); and category III, in which meningitis was neither the underlying nor immediate cause of death (23%; median duration of survival, 32 days) . In a substantial proportion of adults hospitalized with community-acquired bacterial meningitis, meningitis was neither the immediate nor the underlying cause of death . A 14-day survival end point discriminated between deaths attributable to meningitis and those with another cause. Appl Environ Microbiol, 2001 Sep, 67(9), 3795 - 801 Light conditions affect the measurement of oceanic bacterial production via leucine uptake; Moran XA et al.; The effect of irradiance in the range of 400 to 700 nm or photosynthetically active radiation (PAR) on bacterial heterotrophic production estimated by the incorporation of 3H-leucine (referred to herein as Leu) was investigated in the northwestern Mediterranean Sea and in a coastal North Atlantic site, with Leu uptake rates ranging over 3 orders of magnitude . We performed in situ incubations under natural irradiance levels of Mediterranean samples taken from five depths around solar noon and compared them to incubations in the dark . In two of the three stations large differences were found between light and dark uptake rates for the surface most samples, with dark values being on average 133 and 109% higher than in situ ones . Data obtained in coastal North Atlantic waters confirmed that dark enclosure may increase Leu uptake rates more than threefold . To explain these differences, on-board experiments of Leu uptake versus irradiance were performed with Mediterranean samples from depths of 5 and 40 m . Incubations under a gradient of 12 to 1,731 micromol of photons m(-2) x s(-1) evidenced a significant increase in incorporation rates with increasing PAR in most of the experiments, with dark-incubated samples departing from this pattern . These results were not attributed to inhibition of Leu uptake in the light but to enhanced bacterial response when transferred to dark conditions . The ratio of dark to light uptake rates increased as dissolved inorganic nitrogen concentrations decreased, suggesting that bacterial nutrient deficiency was overcome by some process occurring only in the dark bottles. Trends Immunol, 2001 Sep, 22(9), 497 - 501 Bacterial superantigens: provocateurs of gut dysfunction and inflammation? McKay DM. Inflammatory bowel diseases (IBDs) are chronic debilitating conditions, which impair the patient's quality of life significantly . Among them, Crohn's disease and ulcerative colitis are idiopathic disorders for which an infective etiology has long been sought . Here, we present an opinion in support of the hypothesis that bacterial superantigens can participate in the initiation, exaggeration or reactivation of enteric inflammatory disease, at least in some patients . Although the identification of a specific pathogen responsible for IBD remains a worthy pursuit, an awareness of the response to bacterial products per se will be of value in providing a comprehensive understanding of enteric pathophysiological mechanisms and their potential role in IBDs. J Am Chem Soc, 2001 Sep 5, 123(35), 8550 - 63 Modeling the bacterial photosynthetic reaction center . 4 . The structural, electrochemical, and hydrogen-bonding properties of 22 mutants of Rhodobacter sphaeroides; Hughes JM et al.; Site-directed mutagenesis has been employed by a number of groups to produce mutants of bacterial photosynthetic reaction centers, with the aim of tuning their operation by modifying hydrogen-bond patterns in the close vicinity of the "special pair" of bacteriochlorophylls P identical with P(L)P(M) . Direct X-ray structural measurements of the consequences of mutation are rare . Attention has mostly focused on effects on properties such as carbonyl stretching frequencies and midpoint potentials to infer indirectly the induced structural modifications . In this work, the structures of 22 mutants of Rhodobacter sphaeroides have been calculated using a mixed quantum-mechanical molecular-mechanical method by modifying the known structure of the wild type . We determine (i) the orientation of the 2a-acetyl groups in the wild type, FY(M197), and FH(M197) series mutants of the neutral and oxidized reaction center, (ii) the structure of the FY(M197) mutant and possible water penetration near the special pair, (iii) that significant protein chain distortions are required to assemble some M160 series mutants (LS(M160), LN(M160), LQ(M160), and LH(M160) are considered), (iv) that there is competition for hydrogen-bonding between the 9-keto and 10a-ester groups for the introduced histidine in LH(L131) mutants, (v) that the observed midpoint potential of P for HL(M202) heterodimer mutants, including one involving also LH(M160), can be correlated with the change of electrostatic potential experienced at P(L), (vi) that hydrogen-bond cleavage may sometimes be induced by oxidation of the special pair, (vii) that the OH group of tyrosine M210 points away from P(M), and (viii) that competitive hydrogen-bonding effects determine the change in properties of NL(L166) and NH(L166) mutants . A new technique is introduced for the determination of ionization energies at the Koopmans level from QM/MM calculations, and protein-induced Stark effects on vibrational frequencies are considered. Appl Microbiol Biotechnol, 2001 Jun, 55(6), 673 - 9 Bacterial cellulose production under oxygen-enriched air at different fructose concentrations in a 50-liter, internal-loop airlift reactor; Chao Y et al.; Bacterial cellulose (BC) production by Acetobacter xylinum subsp . sucrofermentans BPR2001 was carried out in a 50-1 internal-loop airlift reactor in air at an initial fructose concentration of 40 g/l . The BC production rate was 0.059 g/l per h . When oxygen-enriched air was supplied instead of air, the BC production rate increased to 0.093 g/l per h, and the BC yield was enhanced from 11% in air to 18% . When the initial fructose concentrations were varied from 30 to 70 g/l, the highest BC yield (35%) the highest production rate (0.22 g/l x per h), and the highest concentration of BC produced (10.4 g/l) were observed at 60-70 g/l fructose . From the carbon mass balance calculated at the final stage of cultivation, it was observed that enhanced BC production was reflected as a decrease in both CO2 evolution and the concentration of other unknown substances, suggesting the efficient utilization of energy for BC synthesis despite O2 limitation. Eur J Epidemiol, 2001, 17(1), 89 - 95 Risk factors for and relationship between bacterial vaginosis and cervicitis in a high risk population for cervicitis in Southern Iran; Keshavarz H et al.; In 1990, a study of the reproductive habits and cervical pathology in women of the Qashgha'i nomadic tribe, resulted in a high prevalence of cervicitis . This led us to explore the likely infectious agents responsible for a such high prevalence; to assess the difference in cervicitis rates between nomadic and non-nomadic populations in the same area; and to determine the risk factors for and the relationship between cervicitis and bacterial vaginosis (BV) . In 1996-1997 a study was carried out of 839 married women of the Qashgha'i, 274 of the Lor nomadic tribes, and 388 non-nomadic urban women . A gynaecological examination, Pap smear and vaginal secretion for assessing BV by gram staining were performed . Data was analysed by logistic regression . Backward stepwise regression was used to assess multivariable effects on risk of cervicitis . The prevalence of cervicitis was 88% in the Qashgha'i, 85% in the Lor and 71% in the urban population . In the multivariate backward stepwise regression analysis for predictors of cervicitis in the Qashgha'i, significant factors were decreased association with those over 40 (p < 0.004) and postpartum bleeding . In the Lor tribe the predictors were an increased risk after more than four pregnancies (p < 0.01) and the use of contraception . Among the urban population, the risk of cervicitis was increased with the use of oral contraceptive previously (p < 0.03) or currently (p < 0.01) . BV was strongly associated with cervicitis, with a relatively high attributable risk . Both sexual and childbirth exposures may be associated with cervicitis in these populations. Stat Med, 2001 Sep 15-30, 20(17-18), 2561 - 71 Statistical considerations of FDA and CPMP rules for the investigation of new anti-bacterial products; Rohmel J; In this paper I investigate statistical properties of some guidance given by the FDA and by the CPMP on the planning, conduct and analysis of clinical trials with new anti-bacterial substances using an active control design . It is demonstrated that the non-inferiority margin proposed by the FDA has some undesirable features, and that the CPMP guidance may need further interpretation with respect to a statement that the non-inferiority margin may be smaller than 10 per cent for response rates >90 per cent . A new margin is proposed that combines the desirable properties from both the FDA and the CPMP guidance . It is also shown that the approximate unconditional tests that are in use in such trials are quite unreliable with respect to preserving the nominal type I error . Unconditional exact tests are presented as a remedy for this issue . J Endotoxin Res, 2000, 6(6), 489 - 91 MD-2 binds to bacterial lipopolysaccharide; Viriyakosol S et al.; Many LPS binding proteins have been described, but the exact nature of the LPS receptors that signal cells remains unclear . MD-2 is a molecule that is found in association with Toll-like receptor 4, which has been shown to be a receptor for LPS . We have produced human MD-2 in baculovirus and tested it for LPS binding . MD-2 binds the lipid A region of LPS without the need for LPS binding protein . These data suggest that MD-2 may be binding LPS as part of the TLR4 receptor complex. J Endotoxin Res, 2000, 6(4), 313 - 9 Bacterial endotoxin (lipopolysaccharide) stimulates the rate of iron oxidation; Roth RI et al.; Bacterial endotoxin (lipopolysaccharide) has affinity for a number of cations, including iron . Previous investigations have demonstrated that lipopolysaccharide can affect the oxidation rate of iron; heme-bound ferrous iron in hemoglobin is oxidized to ferric iron when hemoglobin binds lipopolysaccharide . In the present study, we directly examined the interaction between lipopolysaccharide and iron . Lipopolysaccharide caused a concentration-dependent increase in the rate of iron oxidation, with up to a 23-fold increase in oxidation in the presence of 200 microg/ml Escherichia coli lipopolysaccharide . This effect was seen both with several carbohydrate-rich smooth lipopolysaccharides and also with carbohydrate-poor rough lipopolysaccharide . Extensively deacylated rough lipopolysaccharide had no effect, suggesting a role of the fatty acid components of lipopolysaccharide in this process . Purified lipid A produced inconsistent results: some preparations stimulated iron oxidation and others did not . A series of sugars, starches and a preparation of purified O-chain polysaccharide (the carbohydrate portion of the lipopolysaccharide macro-molecule) had no effect on the rate of iron oxidation, whereas phospholipid-enriched brain tissue extracts (similar to the lipid A component of lipopolysaccharide) stimulated oxidation . We conclude that the lipid moiety of bacterial lipopolysaccharide is responsible for the stimulation of iron oxidation . This process may contribute to the ability of lipopolysaccharide to cause oxidation of heme-bound iron in hemoglobin. Anal Biochem, 2001 Sep 1, 296(1), 73 - 82 Quantification of bacterial polysaccharides by the purpald assay: measurement of periodate-generated formaldehyde from glycol in the repeating unit; Lee CH et al.; We have adapted the purpald assay for measurement of bacterial polysaccharides (PS) containing substituted and/or unsubstituted glycol (SG or UG) in residues such as glycerol, ribitol, arabinitol, furanosyl galactose, and sialic acid . For the purpald assay of UG-containing PS, 50 microL of PS samples was consecutively reacted with 50 microL of 16 mM NaIO4 for 20 min, 50 microL of 136 mM purpald reagent in 2 N NaOH for 20 min, and 50 microL of 64 mM NaIO4 for 20 min in a 96-well tissue culture plate followed by a measurement of absorbance at 550 nm with a plate reader . For SG-containing PS, conversion of SG to UG with 25 micro;L of 0.3 N NaOH, 1 h at room temperature for de-O-acetylation followed by 25 microL of 0.6 M H2SO4, 1 h at 80 degrees C for acid hydrolysis of PS precedes the periodate treatment in the purpald assay . The concentration of the samples can be calculated from the sample absorbance and the reference standard curve constructed from the reference concentrations of the same PS (well-characterized) and their corresponding absorbance values assayed in the same plate . The purpald assay provides a tool in addition to the existing ones for the measurement of glycol-containing PS . Among the usefulness of this method are the determinations of the glycerol content in the phospho-glycerol-containing PS and the SG and UG contents and structural integrity in PS and conjugate vaccines . Genetika, 2001 Jun, 37(6), 745 - 53 {Transgenic Tobacco plants expressing bacterial genes encoded the thermostable glucanases}; Movsesian NR et al.; It is shown that bacterial genes for thermostable beta-glucanases are expressed retaining their activity and substrate specificity . The leader peptide of the carrot extensin exerts effective secretion of the bacterial enzymes into the intercellular space of the plant tissue . Expression of the bacterial gene for beta-1,3-glucanase in plant tissues alters their morphogenetic potential . Regeneration of shoots from the calli of these plant lines requires a six- to eightfold increase in cytokinin (6-BAP) concentration in comparison with the control lines and the transgenic lines expressing beta-1,3-1,4-glucanase . Rooting of transgenic plants expressing the bacterial gene for beta-1,3-glucanase occurs much faster . The transgenic plants obtained in the study are proposed as model objects for investigating the role of glucanases in plants. Eur J Ultrasound, 2001 Jul, 13(3), 201 - 4 Hyperechoic focal bacterial nephritis: findings on contrast-enhanced Colour Doppler ultrasound; Esteban JM et al.; We report a case of atypical focal bacterial nephritis (lobar nephronia) simulating a renal mass on gray-scale ultrasound, describing the findings on Colour Doppler ultrasound before and after administration of a galactose-based ultrasound contrast agent. Infect Dis Obstet Gynecol, 2001, 9(3), 133 - 41 A multicenter study of bacterial vaginosis in women with or at risk for human immunodeficiency virus infection; Warren D et al.; BACKGROUND: Bacterial vaginosis is a common gynecologic infection that has been associated with a variety of gynecologic and obstetric complications, including pelvic inflammatory disease, postabortal infection and premature delivery . Recent studies suggest that bacterial vaginosis may increase a woman's risk for human immunodeficiency virus (HIV) . We undertook this study to assess whether the prevalence and characteristics of bacterial vaginosis differed according to HIV status in high-risk US women . METHODS: Prevalence of bacterial vaginosis was assessed by Gram's stain and clinical criteria for 854 HIV-infected and 434 HIV-uninfected women enrolled in the HIV Epidemiology Research (HER) Study . Multiple logistic regression techniques were used to determine whether HIV infection independently predicted bacterial vaginosis . RESULTS: Almost half (46%) the women had bacterial vaginosis by Gram's stain . The prevalence of bacterial vaginosis was 47% in the HIV-positive women compared with 44% in the HIV-negative women; this difference was not statistically significant (p = 0.36) . After adjustment for other covariates, HIV-positive women were more likely than HIV-negative women to have bacterial vaginosis (odds ratio (OR) 1.31; 95% confidence interval (CI) 1.01-1.70) by Gram's stain but not by clinical criteria (OR 1.16; CI 0.87-1.55) . Among HIV-positive women, use of antiretroviral drugs was associated with a lower prevalence of bacterial vaginosis (adjusted OR 0.54; Cl 0.38-0.77) . CONCLUSIONS: In this cross-sectional analysis of high-risk US women, HIV infection was positively correlated with bacterial vaginosis diagnosed by Gram's stain. Biotechniques, 2001 Aug, 31(2), 355, 358 - 62 Development of simple sequence repeat markers from bacterial artificial chromosomes without subcloning; Qi X et al.; Simple sequence repeats (SSRs) were isolated from pearl millet bacterial artificial clones (BACs) without any subcloning steps . SSR sequences were targeted using 3' end-anchored SSR primers . Flanking sequences were isolated by suppression PCR . In this pilot study, 25 SSR markers have been developed from 40 BAC pools, comprising a total of 384 clones . This novel way to develop new markers has the added advantage that mapping the SSR markers will anchor individual BACs to the genetic maps and, thus, facilitate the construction of BAC contigs. Genetics, 2001 Aug, 158(4), 1711 - 24 Bacterial artificial chromosome-based physical map of the rice genome constructed by restriction fingerprint analysis; Tao Q et al.; Genome-wide physical mapping with bacteria-based large-insert clones (e.g., BACs, PACs, and PBCs) promises to revolutionize genomics of large, complex genomes . To accelerate rice and other grass species genome research, we developed a genome-wide BAC-based map of the rice genome . The map consists of 298 BAC contigs and covers 419 Mb of the 430-Mb rice genome . Subsequent analysis indicated that the contigs constituting the map are accurate and reliable . Particularly important to proficiency were (1) a high-resolution, high-throughput DNA sequencing gel-based electrophoretic method for BAC fingerprinting, (2) the use of several complementary large-insert BAC libraries, and (3) computer-aided contig assembly . It has been demonstrated that the fingerprinting method is not significantly influenced by repeated sequences, genome size, and genome complexity . Use of several complementary libraries developed with different restriction enzymes minimized the "gaps" in the physical map . In contrast to previous estimates, a clonal coverage of 6.0-8.0 genome equivalents seems to be sufficient for development of a genome-wide physical map of approximately 95% genome coverage . This study indicates that genome-wide BAC-based physical maps can be developed quickly and economically for a variety of plant and animal species by restriction fingerprint analysis via DNA sequencing gel-based electrophoresis. Clin Infect Dis, 2001 Sep 15, 33(6), 894 - 6 Epub 2001 Aug 10. Association between bacterial vaginosis and expression of human immunodeficiency virus type 1 RNA in the female genital tract; Cu-Uvin S et al.; We assessed the effect of lower genital tract infections on human immunodeficiency virus type 1 (HIV-1) RNA shedding in the female genital tract . Bacterial vaginosis was significantly associated with HIV-1 RNA expression in the female genital tract of HIV-infected women. Arch Microbiol, 2001 Sep, 176(3), 159 - 64 Not quite dead enough: on bacterial life, culturability, senescence, and death; Nystrom T; A number of regulatory networks are functionally integrated in starving cells of Escherichia coli to reduce oxidation of target macromolecules and to enhance the cell's ability to withstand environmental insults . However, despite the fact that starving wild-type E . coli cells enhance their capacity to manage oxidative stress, the proteins of these cells become increasingly oxidized and the cells gradually lose their ability to reproduce . Indeed, it has been argued that starved and growth-arrested bacterial cells show the same signs of senescence as aging cells of higher organisms and that free radicals may be involved in the gradual loss of bacterial culturability observed in a stationary phase culture . Another model suggests that the apparent loss of viability of starved cells is a programmed and adaptive response in which the cells enter a reversible non-culturable state; the theory of the formation of viable but non-culturable cells . Recent data concerning the physiology and biochemistry of starved E . coli cells favor the model that starvation-induced loss of culturability is the result of stochastic deterioration rather than a programmed and adaptive phenomenon, and these data will be reviewed here. Intervirology, 2001, 44(2-3), 115 - 23 Modulation of gene-gun-mediated Th2 immunity to hepatitis B surface antigen by bacterial CpG motifs or IL-12; Schirmbeck R et al.; Using different DNA vaccination techniques, we studied the IgG1/IgG2a antibody and MHC-I-restricted cytotoxic T lymphocyte (CTL) responses to the hepatitis B surface antigen (HBsAg) in mice . A single intramuscular injection of 100 microg HBsAg-encoding pCI/S plasmid DNA efficiently primed IgG2a antibody (IgG1/IgG2a ratio <0.3) and CTL responses to HBsAg (Th1 immunity) . In contrast, a single intradermal injection of 1 microg of particle-coated pCI/S DNA with the gene-gun-primed IgG1 antibody responses to HBsAg (IgG1/IgG2a ratio >80) but there was no CTL response (Th2 immunity) . Injection of immune-stimulating CpG-containing oligodeoxy-nucleotides (ODN) into the skin area used for gene-gun-mediated pCI/S DNA delivery shifted the polarization of the response towards Th1 immunity . A similar shift from Th2 to Th1 immunity was observed when the skin area used for gene-gun-mediated DNA transfer was conditioned by injection of recombinant IL-12 . DNA vaccination can thus prime polarized immunity to HBsAg . The polarization of immunity is determined by the technique of plasmid DNA delivery as well as by conditions of the tissue into which DNA is inoculated . Th1 immunity to HBsAg (primed by injection of naked pCI/S DNA) dominated Th2 immunity (primed by gene-gun-mediated pCI/S DNA) . In contrast, an established HBsAg-specific Th2 immunity was readily shifted towards Th1 immunity (including specific CTL priming) by an intramuscular boost injection of pCI/S DNA . These data contribute to the rational design of DNA vaccination strategies to efficiently prime anti-viral Th1 immune effector specificities using the gene gun . Shock, 2001 Aug, 16(2), 159 - 62 Poly(adp-ribose) synthetase inhibition reduces bacterial translocation in rats after endotoxin challenge; Taner AS et al.; We investigated whether 3-aminobenzamide (3-AB), a poly(ADP-ribose) synthetase (PARS) inhibitor, reduces bacterial translocation (BT) after intraperitoneal endotoxin administration . Wistar rats were randomized to receive intraperitoneal saline (control, n = 6); endotoxin (n = 8); 3-AB (n = 6); and 3-AB plus endotoxin (n = 8) . Six hours later, to evaluate the endotoxin-related intestinal injury and BT, tissue and blood samples were collected . Administration of intraperitoneal endotoxin caused severe intestinal injury and BT to mesenteric lymph nodes . PARS inhibition with 3-AB completely prevented endotoxin-induced BT . No colony-forming bacteria was isolated from the samples obtained from 3-AB-pretreated animals under endotoxin challenge . Treatment with 3-AB significantly reduced the endotoxin-induced intestinal mucosal injury . The inhibition of PARS by its blocker 3-aminobenzamide during endotoxemia prevents bacterial translocation and intestinal injury in rats . PARS activation may provide a novel therapeutic approach in reducing gut barrier failure seen in endotoxemia. Dig Dis Sci, 2001 Aug, 46(8), 1668 - 76 Expression of proinflammatory cytokines and their inhibitors during the course of spontaneous bacterial peritonitis; Rodriguez-Ramos C et al.; The aim of this work was the evaluation, in cirrhotic patients with noninfected ascites and with spontaneous bacterial peritonitis (SBP), of serum and ascitic fluid levels of proinflammatory cytokines {interleukin (IL) 1-beta, tumor necrosis factor alpha (TNF-alpha), and IL6} and antiinflammatory compounds {IL10, soluble IL-1 receptor antagonist (sIL-1Ra), soluble receptors of TNF p55 and p75 (sTNFR55 and sTNFR75), and soluble receptor of IL6 (sIL6R)}, as well as their relationship with the outcome of the infection in those with SBP . These molecules were assayed by ELISA in noninfected cirrhotic controls (n = 15), patients with SBP (n = 32), and healthy controls (n = 20) . Serum levels of IL6 and of the majority of antiinflammatory mediators, sIL1Ra, sTNFR75, and sIL6R, were higher in control cirrhotic patients compared to healthy subjects . SBP was associated with significantly elevated ascitic fluid levels of every one of the proinflammatory cytokines compared to those in cirrhotic controls . Also, serum levels of IL10 and both TNF receptors and ascitic fluid levels of sIL1Ra and sTNFR55 were higher in patients with SBP compared to cirrhotic controls . Ascitic fluid levels of proinflammatory cytokines decreased rapidly after resolution of the infection; however, nonsignificant changes were detected in ascitic fluid concentrations of antiinflammatory molecules . Thus, elevated levels of antiinflammatory compounds both in noninfected cirrhotic patients and in patients with SBP suggest a regulatory control of the inflammatory process by these molecules in liver cirrhosis patients. Dig Dis Sci, 2001 Aug, 46(8), 1657 - 62 Hyperbaric oxygen prevents bacterial translocation in rats with obstructive jaundice; Akin ML et al.; This study was designed to demonstrate bacterial translocation following bile duct ligation and investigate preventive effects of hyperbaric oxygen on obstructive jaundice-related bacterial translocation in an animal model . Hyperbaric oxygen treatment significantly reduced the endogenous colony counts in distal ileum of normal rats both in the short (two days) and long (seven days) term . Endogenous bacteria in distal ileum significantly increased in bile duct ligated rats in the short and long term, and presence of bacterial translocation was proven by bacterial growth in mesenteric lymph nodes, liver, spleen, and blood . Short- and long-term hyperbaric oxygen treatments significantly reduced the intestinal colony counts and prevented the bacterial translocation almost completely in rats with bile duct ligation . It is concluded that obstructive jaundice causes bacterial overgrowth and translocation, and hyperbaric oxygen treatment can prevent both bacterial overgrowth and translocation effectively. Childs Nerv Syst, 2001 Aug, 17(8), 453 - 6 Interleukin-1beta and tumor necrosis factor-alpha in cerebrospinal fluid of children with bacterial meningitis; Tang RB et al.; Certain cytokines may contribute to the sequence of events that lead to meningeal inflammation in bacterial meningitis . The purpose of this study was to determine the levels of cytokines in the cerebrospinal fluid (CSF) of children with bacterial meningitis and aseptic meningitis of different etiologies . We determined the concentrations of interleukin-1beta (IL-1beta) and tumor necrosis factor (TNF-alpha) in the CSF of 171 specimens of 144 patients whose cases were classified as follow: bacterial meningitis (n=23), aseptic meningitis (n=26) and non-meningitis (n=95) . The detectable IL-1beta concentration (> or =20 pg/ml) in the bacterial meningitis, aseptic meningitis and non-meningitis groups were observed with 78.3%, 3.8%, and 8.4%, respectively . Significantly higher serum IL-1beta concentrations were detected in those with bacterial meningitis than those with aseptic meningitis (538.93+/-605.32 pg/ml vs 2.52+/-11.57 pg/ml; P<0.001) or among non-meningitis subjects (2.90+/-11.91 pg/ml; P<0.001) . The mean TNF-alpha concentration was 148.74+/-338.77 pg/ml . There was significantly more TNF-alpha than aseptic meningitis (6.85+/-17.93 pg/ml; P<0.001) or non-meningitis (7.67+/-16.07 pg/ml; P<0.001) . With regard to diagnosis, measurement of IL-1beta and TNF-alpha levels showed sensitivities of 78% and 74%, respectively; specificities of 96% and 81%, respectively . It is suggested that the levels of these cytokines, especially IL-1beta and TNF-alpha, are useful markers for distinguishing bacterial meningitis from aseptic meningitis. Braz J Infect Dis, 2001 Jun, 5(3), 136 - 42 Comparative study of bacterial infection prevalence between cirrhotic patients with and without upper gastrointestinal bleeding; Almeida D et al.; Bacterial infection is a frequent complication in patients with chronic liver disease, mainly during the advanced stages . There is evidence that the main factors that contribute to a predisposition to infection in cirrhotic patients are related to hepatic failure with consequent immunodeficiency . Invasive procedures (diagnostic or therapeutic) can predispose to bacterial infections, and upper gastrointestinal bleeding (UGB) is considered a potentially important risk factor . A group of cirrhotic patients (child B and C Pugh groups) were evaluated retrospectively by chart reviews regarding the prevalence of bacterial infection during hospitalization to determine whether UGB was a risk factor . An infection was considered present if a specific organ system was identified or if fever (> 38(o)C) persisted for more than 24 hours with associated leukocytosis . Spontaneous bacterial peritonitis was based on classical criteria . Eighty-nine patients were evaluated . Fourty-six patients presented with UGB, and 43 patients had no UGB (control) . There were infections recorded in 25/46 (54%) patients with UGB, and 15/43 (35%) in those without UGB (p=0.065) . The ratio of the number of infections/admitted patients, was significantly larger in the group with UGB (0.78 +/- 0.89 vs . 0.39 +/- 0.62; p=0.028) since patients had more than one infection . In the UGB group compared to non UGB group, ascites was more frequent (67% vs . 42%; p=0.027); they were more likely to have undergone endoscopic procedures (p<0.001) and the mean +/- SD for platelets count was smaller (96,114 +/- 57,563 vs 145,674 +/- 104,083; p=0.007) . The results show that UGB is an important contribution to bacterial infection among Child B and C cirrhotic patients. Crit Care Med, 2001 Aug, 29(8), 1539 - 43 Quality of life after severe bacterial peritonitis and infected necrotizing pancreatitis treated with open management of the abdomen and planned re-operations; Bosscha K et al.; OBJECTIVE: To determine quality of life after severe bacterial peritonitis and infected necrotizing pancreatitis treated with open management of the abdomen and planned re-operations . DESIGN: Retrospective chart review . SETTING: University hospital intensive care unit, general wards, and outpatient department . PATIENTS: Forty-one patients who survived severe bacterial peritonitis and infected necrotizing pancreatitis treated with open management of the abdomen and planned re-operations . INTERVENTIONS: None . MEASUREMENTS AND MAIN RESULTS: Over a period of 7 yrs, 95 patients underwent open management of the abdomen and planned re-operations for severe bacterial peritonitis and infected necrotizing pancreatitis . Thirty-nine patients died during the initial intensive care unit stay and 12 as a result of nonperitonitis-related systemic diseases after discharge . Four patients were lost or excluded from final analysis . Long-term morbidity and quality of life using Karnofsky and Rankin scores at discharge and at follow-up at least 1 yr after discharge (mean: 4 yrs) and the Sickness Impact Profile (SIP) were determined . The remaining 41 patients reviewed showed significant long-term morbidity, including dysfunction of the abdominal wall resulting from herniation, persistent polyneuropathy, and mental disorders needing psychiatric support . Patients having persistent polyneuropathy and, to a lesser extent, mental disorders, showed significantly lower Karnofsky, higher Rankin, and higher SIP scores . After discharge, performance status of patients improved significantly, as shown by higher Karnofsky and lower Rankin scores, and, because Karnofsky and Rankin scores are closely related to SIP scores, higher SIP scores . Especially in measuring quality of life in terms of social and role management, assessment of the SIP proved to have additional value . CONCLUSIONS: About three-quarters of patients who survive open management of the abdomen and planned re-operations for severe bacterial peritonitis and infected necrotizing pancreatitis regain a good quality of life . Some patients, especially those who suffer from persistent polyneuropathy and mental disorders, show restrictions in daily life. Am J Physiol Lung Cell Mol Physiol, 2001 Sep, 281(3), L537 - 43 Selective inhibition of COX-2 improves early survival in murine endotoxemia but not in bacterial peritonitis; Reddy RC et al.; Prostaglandins of the E series are believed to act as important mediators of several pathophysiological events that occur in sepsis . Studies were performed to evaluate the effect of cyclooxygenase (COX)-2-specific inhibition on the outcome in murine endotoxemia and cecal ligation and puncture (CLP) . We observed a significant time-dependent upregulation of PGE(2) production in both blood and lung homogenates of mice administered lipopolysaccharide intraperitoneally, which was nearly completely suppressed by the administration of the COX-2 inhibitor NS-398 . Treatment with NS-398 significantly improved early but not late survival in lipopolysaccharide-challenged mice . On the contrary, elevated PGE(2) levels were found in bronchoalveolar lavage fluid but not in plasma of mice subjected to CLP (21 gauge) . Pretreatment with NS-398 failed to significantly improve survival in CLP mice . No significant differences were noted in plasma or lung homogenate proinflammatory cytokine levels or lung neutrophil sequestration between the NS-398-treated and control groups . These results demonstrate that selective COX-2 inhibition confers early but not long-term benefits without affecting the expression of proinflammatory cytokines or the development of lung inflammation. J Vet Med Sci, 2001 Jul, 63(7), 811 - 3 Mast cell MMP-9 production enhanced by bacterial lipopolysaccharide; Tanaka A et al.; Although mast cells contribute to host protective immunity against bacterial infections, the exact mechanism of their recruitment at the affected site has been unclear . Recently, we have reported that both mouse and human mast cells are capable of producing matrix metalloproteinase (MMP)-9, a matrix-degrading enzyme necessary for leukocyte transmigration . Here, we demonstrated that bacterial lipopolysaccharide (LPS) enhanced MMP-9 production of mouse bone marrow derived-cultured mast cells . This action of LPS was partially suppressed by the pretreatment of cultured mast cells with a protein kinase C (PKC) inhibitor, indicating the possible involvement of PKC signaling pathways in the production of MMP-9 by LPS . Thus, these suggest the upregulation of mast cell MMP-9 by bacterial components, thereby resulting in their migration at the affected site. Carbohydr Res, 2001 Aug 23, 334(2), 97 - 103 Synthesis of the milk oligosaccharide 2'-fucosyllactose using recombinant bacterial enzymes; Albermann C et al.; The enzymatic synthesis of GDP-beta-L-fucose and its enzymatic transfer reaction using recombinant enzymes from bacterial sources was examined . The GDP-D-mannose 4,6-dehydratase and the GDP-4-keto-6-deoxy-D-mannose 3,5-epimerase-4-reductase from Escherichia coli K-12, respectively, were used to catalyse the conversion of GDP-alpha-D-mannose to GDP-beta-L-fucose with 78% yield . For the transfer of the L-fucose to an acceptor, we cloned and overproduced the alpha-(1-->2)-fucosyltransferase (FucT2) protein from Helicobacter pylori . We were able to synthesise 2'-fucosyllactose using the overproduced FucT2 enzyme, enzymatically synthesised GDP-L-fucose and lactose . The isolation of 2'-fucosyllactose was accomplished by anion-exchange chromatography and gel filtration to give 65% yield. Zhonghua Zheng Xing Shao Shang Wai Ke Za Zhi, 1999 May, 15(3), 202 - 5 {Experimental study and preliminary clinical application of bacterial collagenase in catabolizing scars}; Cheng H et al.; OBJECTIVE: To investigate the mechanism of collagenase in degradation of hypertrophic scars and observe the clinical effects of this therapy . METHODS: Both animal experiment and clinical trial were conducted . RESULTS: The injection of collagenase into the hypertrophic scar tissues in nude mice resulted in 86% volume reduction after two injections within two weeks, while the control tissues reduced only by 35% during the same time . Clinically, 13 cases were treated with intralesional injection of bacterial collagenase . The volume reduction rate was 46.92% in average within two weeks . The volume reduction in 4 of 13 cases was above 50% . Three to sixteen months' follow-up of five patients revealed that only one case of keloid recurred after treatment in the second month . Examinations of histological sections and TEM showed the dissolved collagen fiber clearly . CONCLUSION: Collagenase can degrade collagen fiber directly . The prompt significant effects and the mild complications make it a prospective therapy. EMBO J, 2001 Aug 15, 20(16), 4408 - 13 Projection structure and molecular architecture of OxlT, a bacterial membrane transporter; Heymann JA et al.; The major facilitator superfamily (MFS) represents the largest collection of evolutionarily related members within the class of membrane 'carrier' proteins . OxlT, a representative example of the MFS, is an oxalate-transporting membrane protein in Oxalobacter formigenes . From an electron crystallographic analysis of two-dimensional crystals of OxlT, we have determined the projection structure of this membrane transporter . The projection map at 6 A resolution indicates the presence of 12 transmembrane helices in each monomer of OxlT, with one set of six helices related to the other set by an approximate internal two-fold axis . The projection map reveals the existence of a central cavity, which we propose to be part of the pathway of oxalate transport . By combining information from the projection map with related biochemical data, we present probable models for the architectural arrangement of transmembrane helices in this protein superfamily. EMBO J, 2001 Aug 15, 20(16), 4325 - 31 New EMBO members' review: viral and bacterial proteins regulating apoptosis at the mitochondrial level; Boya P et al.; Mitochondrial membrane permeabilization (MMP) is a critical step of several apoptotic pathways . Some infectious intracellular pathogens can regulate (induce or inhibit) apoptosis of their host cells at the mitochondrial level, by targeting proteins to mitochondrial membranes that either induce or inhibit MMP . Pathogen-encoded mitochondrion-targeted proteins may or may not show amino acid sequence homology to Bcl-2-like proteins . Among the Bcl-2-unrelated, mitochondrion-targeted proteins, several interact with the voltage-dependent anion channel (VDAC) or with the adenine nucleotide translocator (ANT) . While VDAC-targeted proteins show homology to VDAC/porin, ANT-targeted proteins possess relatively short cationic binding domains, which may facilitate insertion into the negatively charged inner mitochondrial membrane . It may be speculated that such proteins employ pre-existing host-intrinsic mechanisms of MMP control. Cancer Immunol Immunother, 2001 Jul, 50(5), 241 - 50 Construction, expression and characterisation of a single-chain diabody derived from a humanised anti-Lewis Y cancer targeting antibody using a heat-inducible bacterial secretion vector; Power BE et al.; A single-chain antibody fragment (scFv) of the humanised monoclonal antibody, hu3S193, that reacts specifically with Le(y) antigen expressed in numerous human epithelial carcinomas was constructed . A five-residue linker joined the C-terminus of the V(H) and the N-terminus of the V(L), which prevented V-domain association into a monomeric scFv and instead directed non-covalent association of two scFvs into a dimer or diabody . The diabody was secreted into the E . coli periplasm using a heat-inducible vector, pPOW3, and recovered as a soluble, correctly processed protein, following osmotic shock or solubilised with 4 M urea from the insoluble fraction . The diabody from both fractions was isolated by a rapid batch affinity chromatography procedure, using the FLAG affinity tag to minimise degradation and aggregation . The purified diabody has an Mr of approximately 54 kDa, was stable and demonstrated similar binding activity as the parent monoclonal antibody, as measured by FACS and BIAcore analyses . The radiolabelled diabody showed a rapid tumour uptake, with fast blood clearance, proving it to be an excellent potential candidate as a tumour-imaging agent. J Chromatogr B Biomed Sci Appl, 2001 Aug 15, 759(2), 237 - 46 High-performance affinity capture-removal of bacterial pyrogen from solutions; Ding JL et al.; Synthetic peptide S3delta has high affinity for bacterial endotoxin or lipopolysaccharide (LPS) . Under tested conditions of pH 5-9 and 0-0.4 M NaCl, the affinity constant, KD ranged from 2.10(-6) to 2 x 10(-9) M(-1) . A novel affinity matrix based on peptide S3delta was developed for removal of LPS from solutions such as: water; buffers with a wide range of ionic strength and pH; medium for cell culture; and protein solutions under optimized conditions . At a starting LPS of approximately 100 EU/ml, a post-purification level below 0.005 EU/ml was achieved. Drug Resist Updat, 1999 Dec, 2(6), 358 - 362 Mining bacterial cell wall biosynthesis with new tools: multitarget screens; Trias J et al.; The cytoplasmic steps of peptidoglycan synthesis remain underexplored for the discovery of novel antibiotics . Pathway screens are well suited to screen for novel inhibitors because several targets are tested at once . Whole-cell based assays are easier to set up but they tend to favor identification of compounds that inhibit enzymes that are at the limiting rate in the pathway . Screens that use purified enzymes are optimized to detect with similar probability inhibitors of any of the targets in the pathway . This approach is being used to identify novel promising molecules . Phys Rev E Stat Nonlin Soft Matter Phys . 2001 Aug;64(2 Pt 1):021910 . Epub 2001 Jul 24. Effects of thermal fluctuation and the receptor-receptor interaction in bacterial chemotactic signaling and adaptation; Shi Y; Bacterial chemotaxis is controlled by the conformational changes of the receptors in response to the change of the ambient chemical concentration . In a statistical mechanical approach, the signaling due to the conformational changes is a thermodynamic average quantity, dependent on the temperature and the total energy of the system, including both ligand-receptor interaction and receptor-receptor interaction . This physical theory suggests to biology an understanding of cooperation in ligand binding and receptor signaling problems . How much experimental support of this approach can be obtained from the currently available data? What are the parameter values? What is the practical information for experiments? Here we make comparisons between the theory and recent experimental results . Although currently comparisons can only be semiquantitative or qualitative, consistency is clearly shown . The theory also helps to sort a variety of data. RNA, 2001 Aug, 7(8), 1165 - 72 The GA motif: an RNA element common to bacterial antitermination systems, rRNA, and eukaryotic RNAs; Winkler WC et al.; Two different transcription termination control mechanisms, the T box and S box systems, are used to regulate transcription of many bacterial aminoacyl-tRNA synthetase, amino acid biosynthesis, and amino acid transport genes . Both of these regulatory mechanisms involve an untranslated mRNA leader region capable of adopting alternate structural conformations that result in transcription termination or transcription elongation into the downstream region . Comparative analyses revealed a small RNA secondary structural element, designated the GA motif, that is highly conserved in both T box and S box leader sequences . The motif consists of two short helices separated by an asymmetric internal loop, with highly conserved GA dinucleotide sequences on either side of the internal loop . Site-directed mutagenesis of this motif in model T and S box leader sequences indicated that it is essential for transcriptional regulation in both systems . This motif is similar to the binding site of yeast ribosomal protein L30, the Snu13p binding sites found in U4 snRNA and box C/D snoRNAs, and two elements in 23S rRNA. Exp Dermatol, 2001 Aug, 10(4), 256 - 63 Bullous pemphigoid sera react specifically with various domains of BP230, most frequently with C-terminal domain, by immunoblot analyses using bacterial recombinant proteins covering the entire molecule; Hamada T et al.; By immunoblot analyses of normal human epidermal extracts, the 230 kDa bullous pemphigoid antigen (BP230) is recognized by most bullous pemphigoid sera . By polymerase chain reaction using keratinocyte cDNA library as a template, we successfully amplified 3 cDNAs of about 3 kb, which covered whole human BP230 molecule . By inserting the cDNAs into bacterial expression vector pGEX, we prepared 3 different recombinant glutathione-S-transferase-fusion proteins, which roughly presented N-terminal domain, central rod domain and C-terminal domain of BP230 . By immunoblotting using these 3 recombinant proteins, we demonstrated that the majority of bullous pemphigoid sera reacted clearly with multiple recombinant proteins of BP230, most frequently with C-terminal domain . We also examined sera of pemphigus vulgaris, pemphigus foliaceus and herpetiform pemphigus that showed BP230-like protein band by immunoblotting of epidermal extracts, as well as paraneoplastic pemphigus, for reactivity with the 3 recombinant proteins . In the study, we found that only very few of these non-bullous pemphigoid sera reacted with some of the recombinant proteins . These results indicate that the BP230 is specifically reacted by bullous pemphigoid sera, and that the immunoblotting using the BP230 recombinant proteins should be a useful tool for the diagnosis of bullous pemphigoid. Arch Microbiol, 2001 Jun, 175(6), 413 - 29 Cell compartmentalisation in planctomycetes: novel types of structural organisation for the bacterial cell; Lindsay MR et al.; The organisation of cells of the planctomycete species Pirellula marina, Isosphaera pallida, Gemmata obscuriglobus, Planctomyces maris and "Candidatus Brocadia anammoxidans" was investigated based on ultrastructure derived from thin-sections of cryosubstituted cells, freeze-fracture replicas, and in the case of Gemmata obscuriglobus and Pirellula marina, computer-aided 3-D reconstructions from serial sections of cryosubstituted cells . All planctomycete cells display a peripheral ribosome-free region, termed here the paryphoplasm, surrounding the perimeter of the cell, and an interior region including any nucleoid regions as well as ribosome-like particles, bounded by a single intracytoplasmic membrane (ICM), and termed the pirellulosome in Pirellula species . Immunogold labelling and RNase-gold cytochemistry indicates that in planctomycetes all the cell DNA is contained wholly within the interior region bounded by the ICM, and the paryphoplasm contains no DNA but at least some of the cell's RNA . The ICM in Isosphaera pallida and Planctomyces maris is invaginated such that the paryphoplasm forms a major portion of the cell interior in sections, but in other planctomycetes it remains as a peripheral zone . In the anaerobic ammonium-oxidising ("anammox" process) chemoautotroph "Candidatus Brocadia anammoxidans" the interior region bounded by ICM contains a further internal single-membrane-bounded region, the anammoxosome . In Gemmata obscuriglobus, the interior ICM-bounded region contains the nuclear body, a double-membrane-bounded region containing the cell's nucleoid and all genomic DNA in addition to some RNA . Shared features of cell compartmentalisation in different planctomycetes are consistent with the monophyletic nature of the planctomycetes as a distinct division of the Bacteria . The shared organisational plan for the planctomycete cell constitutes a new type not known in cells of other bacteria. J Immunol, 2001 Aug 15, 167(4), 1871 - 6 Cutting edge: the nucleotide receptor P2X7 contains multiple protein- and lipid-interaction motifs including a potential binding site for bacterial lipopolysaccharide; Denlinger LC et al.; The nucleotide receptor P2X7 has been shown to modulate LPS-induced macrophage production of numerous inflammatory mediators . Although the C-terminal portion of P2X7 is thought to be essential for multiple receptor functions, little is known regarding the structural motifs that lie within this region . We show here that the P2X7 C-terminal domain contains several apparent protein-protein and protein-lipid interaction motifs with potential importance to macrophage signaling and LPS action . Surprisingly, P2X7 also contains a conserved LPS-binding domain . In this report, we demonstrate that peptides derived from this P2X7 sequence bind LPS in vitro . Moreover, these peptides neutralize the ability of LPS to activate the extracellular signal-regulated kinases (ERK1, ERK2) and to promote the degradation of the inhibitor of kappaB-alpha isoform (IkappaB-alpha) in RAW 264.7 macrophages . Collectively, these data suggest that the C-terminal domain of P2X7 may directly coordinate several signal transduction events related to macrophage function and LPS action. Mol Microbiol, 2001 Jul, 41(2), 289 - 97 Evolution of a molecular switch: universal bacterial GTPases regulate ribosome function; Caldon CE et al.; The GTPases comprise a protein superfamily of highly conserved molecular switches adapted to many diverse functions . These proteins are found in all domains of life and often perform essential roles in fundamental cellular processes . Analysis of data from genome sequencing projects demonstrates that bacteria possess a core of 11 universally conserved GTPases (elongation factor G and Tu, initiation factor 2, LepA, Era, Obg, ThdF/TrmE, Ffh, FtsY, EngA and YchF) . Investigations aimed at understanding the function of GTPases indicate that a second conserved feature of these proteins is that they elicit their function through interaction with RNA and/or ribosomes . An emerging concept suggests that the 11 universal GTPases are either necessary for ribosome function or transmitting information from the ribosome to downstream targets for the purpose of generating specific cellular responses . Furthermore, it is suggested that progenitor GTPases were early regulators of RNA function and may have existed in precursors of cellular systems driven by catalytic RNA . If this is the case, then a corollary of this hypothesis is that GTPases that do not bind RNA arose at a later time from an RNA-binding progenitor that lost the capability to bind RNA. Contemp Top Lab Anim Sci, 2000 Jul, 39(4), 9 - 12 Verification of bacterial killing effects of cage wash time and temperature combinations using standard penicylinder methods; Wardrip CL et al.; We conducted the present study to evaluate various time and hot-water temperature combinations necessary to kill three common bacterial species in standardized cultures on stainless steel penicylinders, in accordance with methods approved by the Association of Official Analytical Chemists . Exposure for no more than 2 sec to water at 82.2 degrees C killed all three bacterial species, as did exposure for 3 sec to water at 80 degrees C, 4 sec at 77.8 degrees C, and 5 sec at 75.6 degrees C . We conclude that temperatures in the range of 75.6 degrees C to 82.2 degrees C will effectively kill vegetative bacteria in a matter of seconds and that failure to kill these bacteria in cagewash operations, with belt travel times in minutes rather than seconds, is due to other factors that prevent the effective application of sufficiently hot water to the bacterial load. Biotechnol Prog, 2001 Jul-Aug, 17(4), 781 - 5 Effect of addition of water-soluble polysaccharides on bacterial cellulose production in a 50-L airlift reactor; Chao Y et al.; Bacterial cellulose (BC) production was carried out in a batch cultivation of Acetobacter xylinum in a 50-L internal loop airlift reactor by addition of water-soluble polysaccharides into the medium . When 0.1% (w/w) agar was added, BC production reached 8.7 g/L compared with 6.3 g/L in the control, and duration of the cultivation period to reach the maximum concentration of BC was almost half of that without addition of polysaccharides . During cultivation, BC was formed into pellets whose size was smaller when the productivity of BC was higher, indicating that increase in the relative viscosity by addition of polysaccharides hindered formation of large clumps of BC and increase in the volumetric oxygen transfer coefficient at high flow rate led to increase in BC productivity. Pancreas, 2001 Aug, 23(2), 148 - 56 Beneficial effects of growth hormone on bacterial translocation during the course of acute necrotizing pancreatitis in rats; Wang X et al.; Because bacterial translocation from the gut is one of the important sources of bacterial infection in acute necrotizing pancreatitis (ANP) and growth hormone (GH) has the ability to promote the intestinal epithelial proliferation, we investigated the effects of GH on bacterial translocation in a rat ANP model . ANP was induced in rats by injection of 5% sodium taurocholate into the biliopancreatic duct . The rats with ANP were treated with either human recombinant GH or placebo . Laparotomized animals without induction of ANP (sham operation {SO}) served as controls . At 24 hours after operation, blood was drawn for bacterial culture and determination of amylase, lipase, and endotoxin . Peritoneal fluid and specimens of mesenteric lymph nodes (MLN), liver, pancreas, and spleen were taken for bacterial culture by standard techniques . Intestinal mucosal permeability was assessed by measuring the movement of 125I-labeled albumin from blood to intestinal lumen . Insulin-like growth factor-1 (IGF-1) mRNA was detected in the liver and ileum by reverse transcriptase-polymerase chain reaction (RT-PCR) . Morphologic changes of pancreas and ileum were also analyzed . Administration of GH significantly decreased the serum amylase, lipase activities, plasma endotoxin level, and incidence of bacterial translocation . Moreover, the survival rate of ANP rats was improved . The severity of inflammation in pancreas and ileum was alleviated by GH treatment . Ileal mucosal thickness, villus height, and crypt depth in GH treatment rats were obviously increased compared with those of ANP rats . The intestinal permeability was markedly improved in the GH group versus the ANP group . GH treatment resulted in up-regulation of IGF-1 mRNA expression in ileum, but not in liver . These results suggested that exogenous GH had beneficial effects in maintaining the integrity of intestinal mucosal barrier and reducing the incidence of bacterial translocation in rats with ANP . One of the mechanisms might be the up-regulation of IGF-1 mRNA in intestine by GH treatment. J Ethnopharmacol, 2001 Sep, 77(1), 111 - 2 Anti-bacterial activity of Galega officinalis L . (Goat's Rue); Pundarikakshudu K et al.; Alcoholic extracts of Goat's Rue (Galega officinalis L.; Papilionaceae) were tested on Gram +ve and Gram -ve bacteria as the plant was claimed to hasten skin healing after surgery . Ethanolic (60%) extract exhibited significant inhibition on growth of both Gram +ve and Gram -ve bacteria. Semin Neonatol, 2001 Apr, 6(2), 157 - 72 Neonatal bacterial meningitis; Polin RA et al.; Despite major improvements in infant intensive care, neonatal meningitis remains a devastating disease . Survivors of bacterial meningitis are at high-risk for life-long neurological handicaps, and despite a reduction in mortality, the morbidity of neonatal meningitis has not changed substantially over the last thirty years . A substantial improvement in outcome is unlikely to result from further refinements in ICU technology or new antibiotics . However, recent advancements in our understanding of the pathogenesis of meningitis and the pathophysiology of brain injury in meningitis may provide the opportunity to interrupt the mechanisms that allow bacteria to enter the central nervous system and initiate the inflammatory response . Strategies aimed at modulating the inflammatory response must be chosen carefully, so as not to disrupt normal host responses needed for the infant to recover from the infectious episode . Cell Biol Int, 2001, 25(8), 715 - 23 Contaminants within bacterial plasmid preparations trigger apoptosis in liposome transfected OVCAR3, but not in SKOV3 or AZ224 human ovarian cancer cells; Neyns B et al.; Toxicity associated with plasmid/liposome transfection of eucaryote cells has been attributed to the inherent toxicity of cationic lipid formulations and also to bacterial contaminants of plasmid DNA preparations, such as lipopolysaccharides (LPS) . Certain plasmid preparations were observed to trigger apoptosis in DNA/liposome transfected OVCAR3 human epithelial ovarian cancer cells . In contrast, AZ224 and SKOV3 cells were unaffected under the same conditions . Agarose gel electrophoresis with recovery of the plasmid DNA removed the toxic component, but not purification by phenol/chloroform extraction or isopicnic CsCl ultracentrifugation . The toxicity of individual preparations correlated with the concentration of bacterial LPS . However, polymixin B could not neutralise the toxicity and neither could the effect be reproduced by the addition of bacterial LPS to non-toxic plasmid preparations . Surprisingly, the conditioned medium of OVCAR3 cells undergoing apoptosis was found to kill non-transfected OVCAR3 cells but not AZ224 or SKOV3 cells . This observation illustrates the possibility that unpredictable contaminants of bacterial plasmid preparations are able to cause cell death in the context of plasmid/liposome transfection in a cell-type specific way . It emphasizes the importance of achieving maximal plasmid DNA purity when performing DNA transfection experiments that focus on cell survival . Biologicals, 2001 Mar, 29(1), 55 - 8 Interfering effect of diphtheria-tetanus-acellular pertussis combined (DTaP) vaccines on the bacterial endotoxin test; Ochiai M et al.; We evaluated applicability of the endotoxin test to DTaP vaccines . Although no DTaP vaccine batches showed immediate interference with the activating activity of spiked endotoxin on the clotting of Limulus amaebocyte lysate (LAL), a gradually progressing interference depending on the time after spiking was seen for some of the batches . The interfering DTaP vaccine batches, however, showed no significant effect onin vitro TNF-alpha induction in RAW264.7 cells and pyrogenicity in rabbits of spiked endotoxin . Aluminium hydroxide gel in the vaccines was suggested to be one of the causes of the interference . Accordingly, a careful evaluation of the interfering effect was assumed crucial for the effective application of the endotoxin test to check residual biological activity of endotoxin in DTaP vaccines. Cir Pediatr, 2001 Apr, 14(2), 57 - 60 {Bacterial translocation associated with short bowel: role of ileocecal valve and cecum}; Eizaguirre I et al.; Sepsis in short bowel syndrome (SBS) is due in part to bacterial translocation (BT) . Parenteral nutrition (PN) is often necessary in SBS and promotes BT . The presence of ileocecal valve (ICV) has been considered as a good prognostic factor in the outcome of this children . The aim of this study was to asses the effect of the presence or absence of ICV and cecum in five different models of gut resection in the rat . Fifty-five adult Wistar rats were randomly assigned to one of five groups: Group 1 (N = 14): standard rat chow + 80% small bowel resection . Group 2 (N = 10): standard rat chow + 80% small bowel resection including cecum . Group 3 (N = 10): standard rat chow + 80% small bowel resection including ICV . Group 4 (N = 11): NP + 80% small bowel resection . Group 5 (N = 10): NP + 80% small bowel resection including ICV and cecum . Ten days after surgery they were sacrificed and mesenteric lymph nodes (MLN), spleen and peripheral (PBL) and portal blood (POBL) specimens were recovered and cultured . Groups 3 (without ICV, with cecum) and 5 (without ICV, without cecum) showed 60% BT in MLN and POBL, and groups 1 and 4 (with ICV, without cecum) 93% and 91% respectively (p < 0.05) . In PBL, group 3 (without ICV, with cecum) showed also less BT than groups 1 and 4 (10% vs 43% and 55% respectively, p < 0.05) and group 5 (without ICV and cecum) had less BT than groups 1, 2 and 4 (0% vs 43%, 30% and 55%, p < 0.01) . In conclusion, these results suggest that the absence of ICV decreases BT and that the cecum does not seems to play a role on his. J Pediatr Gastroenterol Nutr, 2001 Jul, 33(1), 1 - 10 Bacterial {correction of baterial} translocation in humans; Lichtman SM; Bacterial translocation is a phenomenon in which live bacteria cross the intestinal barrier . The definition may be broadened to include transmural passage of bacterial cell wall components such as lipopolysaccharide and peptidoglycan polysaccharide . After translocation, bacteria or their products reach the mesenteric lymph nodes . From there, it is possible that enteric bacteria, their cell wall components, or both may disseminate throughout the body, causing sepsis, shock, multisystem organ dysfunction, or death of the host . Bacterial translocation and its complications have been shown clearly to occur in animal models, but its existence and importance in humans has been difficult to ascertain . The purpose of this review is to evaluate the data from studies in humans on the occurrence of bacterial translocation and, more importantly, to evaluate its role as a cause of death in humans . Studies from trauma and intensive care centers often imply that bacterial translocation is a major contributor to sepsis, shock, and multisystem organ failure in humans . However, the data reviewed herein do not support that view clearly . Carefully designed studies are needed to determine the relevance of bacterial translocation in human disease. J Clin Pathol, 2001 Aug, 54(8), 619 - 23 Bacterial translocation and immunohistochemical measurement of gut immune function; Woodcock NP et al.; AIMS: The local immune response in the small bowel mucosa might play a role in bacterial translocation (BT) . The aim of this study was to quantify immune cells and secretory antibodies in the small bowel mucosa, and relate this to BT as assessed by culture of a mesenteric lymph node . METHODS: Immunohistochemical techniques were used to measure the frequency of plasma cells and IgA and IgM positive cells in the lamina propria and semiquantitatively to assess mucosal surface IgA and IgM values in small bowel specimens obtained from 11 patients in whom positive evidence of BT had been identified in a mesenteric lymph node harvested at the time of laparotomy . These were compared with similar specimens obtained from 11 patients in whom a similar lymph node had yielded no growth . RESULTS: BT was associated with a significantly increased median frequency of plasma cells (p < 0.01) and IgA positive cells (p < 0.05) in the lamina propria . The frequency of IgM positive cells was also higher in these patients, although this difference was not significant . In addition, semiquantitatively scored IgA and IgM concentrations at the mucosal surface were both significantly higher in the patients in whom BT had been identified (p = 0.006 and 0.016, respectively) . CONCLUSION: Higher numbers of plasma cells and higher IgA and IgM values are present in the small bowel mucosa of patients in whom BT has been shown to occur, suggesting an increased local immune response. DNA Res, 2001 Jun 30, 8(3), 97 - 106 A novel bacterial gene-finding system with improved accuracy in locating start codons; Yada T et al.; Although a number of bacterial gene-finding programs have been developed, there is still room for improvement especially in the area of correctly detecting translation start sites . We developed a novel bacterial gene-finding program named GeneHacker Plus . Like many others, it is based on a hidden Markov model (HMM) with duration . However, it is a 'local' model in the sense that the model starts from the translation control region and ends at the stop codon of a coding region . Multiple coding regions are identified as partial paths, like local alignments in the Smith-Waterman algorithm, regardless of how they overlap . Moreover, our semiautomatic procedure for constructing the model of the translation control region allows the inclusion of an additional conserved element as well as the ribosome-binding site . We confirmed that GeneHacker Plus is one of the most accurate programs in terms of both finding potential coding regions and precisely locating translation start sites . GeneHacker Plus is also equipped with an option where the results from database homology searches are directly embedded in the HMM . Although this option does not raise the overall predictability, labeled similarity information can be of practical use . GeneHacker Plus can be accessed freely at http://elmo.ims.u-tokyo.ac.jp/GH/. Biopolymers, 2001 Oct 5, 59(4), 191 - 204 Comparative rheological behavior of hyaluronan from bacterial and animal sources with cross-linked hyaluronan (hylan) in aqueous solution; Milas M et al.; Using a variety of rheological techniques, the behavior of hyaluronan (M(w) 0.8-2.2 x 10(6)), cross-linked hyaluronan (hylan) (M(w) 1.8-12.5 x 10(6)), and Healon (M(w) approximately 5 x 10(6)) (a proprietary hyaluronan) was studied over a large range of molecular weights . The object was to study the effect of the cross-links in hylan on the various rheological parameters, in comparison with linear hyaluronan . There are significant differences . The Huggins constant and the critical overlap parameter C*{eta} are considerably lower for hylan and an increase in moduli at low frequencies was observed for hylan compared with the hyaluronan samples at all molecular weights studied . The results point to a difference in structure in dilute solution for hylan due to the ability to form networks, which can be removed by pressure filtration . In contrast, we do not find an increase of the steady shear viscosity and elastic modulus at higher concentrations when a homogeneous entangled network is reached . We attribute this behavior to the semirigid character of the hyaluronan chain and to the predominance of entanglements over the cross-link points present in hylan in the semidilute domain . Due to the higher apparent molecular weights that are possible with hylan structures but not with the hyaluronans currently available, a wider range of applications can be achieved with hylans when viscoelasticity is required, particularly for the viscosupplementation of synovial fluid damaged by osteoarthritis . Appl Environ Microbiol, 2001 Aug, 67(8), 3350 - 7 Quantitative analysis of bacterial gene expression by using the gusA reporter gene system; Sun J et al.; An Azospirillum brasilense Sp7 strain containing a plasmid-borne translational cytN-gusA fusion was grown in a continuous culture to quantitatively evaluate the influence of extracellular signals (such as O(2)) on expression of the cytNOQP operon . The dissolved oxygen concentration was shifted at regular time intervals before the steady state was reached . The measured beta-glucuronidase activity was used to monitor cytN gene expression . However, as the beta-glucuronidase activity in the experimental setup not only depended on altered transcription of the hybrid gene when the signal was varied but was also influenced by cellular accumulation, degradation, and dilution of the hybrid fusion protein, a mathematical method was developed to describe the intrinsic properties of the dynamic bioprocess . After identification and validation of the mathematical model, the apparent specific rate of expression of the fusion, which was independent of the experimental setup, could be deduced from the model and used to quantify gene expression regulated by extracellular environmental signals . In principle, this approach can be generalized to assess the effects of external signals on bacterial gene expression. Proc Natl Acad Sci U S A, 2001 Jul 31, 98(16), 9237 - 42 Epub 2001 Jul 24. Human TLR9 confers responsiveness to bacterial DNA via species-specific CpG motif recognition; Bauer S et al.; The Toll-like receptor (TLR) family consists of phylogenetically conserved transmembrane proteins, which function as mediators of innate immunity for recognition of pathogen-derived ligands and subsequent cell activation via the Toll/IL-1R signal pathway . Here, we show that human TLR9 (hTLR9) expression in human immune cells correlates with responsiveness to bacterial deoxycytidylate-phosphate-deoxyguanylate (CpG)-DNA . Notably "gain of function" to immunostimulatory CpG-DNA is achieved by expressing TLR9 in human nonresponder cells . Transfection of either human or murine TLR9 conferred responsiveness in a CD14- and MD2-independent manner, yet required species-specific CpG-DNA motifs for initiation of the Toll/IL-1R signal pathway via MyD88 . The optimal CpG motif for hTLR9 was GTCGTT, whereas the optimal murine sequence was GACGTT . Overall, these data suggest that hTLR9 conveys CpG-DNA responsiveness to human cells by directly engaging immunostimulating CpG-DNA. Proc Natl Acad Sci U S A, 2001 Jul 31, 98(16), 9020 - 5 Epub 2001 Jul 24. Function of the bacterial TATAAT -10 element as single-stranded DNA during RNA polymerase isomerization; Fenton MS et al.; The bacterial TATAAT -10 region sequence was the first promoter element to be identified, but how it functions is still not clear . Because the duplex element is melted during initiation, the effects of substitutions were studied in both single-and double-strand contexts . Band-shift results were particularly unexpected in the context of melted DNA . The effect of the lac UV5-melted -10 region on polymerase binding was found to include a large sequence nonspecific contribution . Instead the dominant role of single-stranded -10 region nucleotides was in directing the isomerization of the RNA polymerase to its heparin resistant form . This role becomes minimal when the melting is extended beyond the -10 region to encompass the transcription start site, as in the final open complex . The duplex binding results are in agreement with previous reports that showed positions -12T and -11A are of primary importance for promoter recognition . Thus the consensus -10 region sequences function in two ways, both before full promoter melting . They stabilize initial polymerase binding via duplex interactions and subsequently as single-stranded DNA they promote enzyme isomerization to the functional form. Gene, 2001 Jul 11, 272(1-2), 291 - 9 Genomic organization and chromosomal localization of the Asna1 gene, a mouse homologue of a bacterial arsenic-translocating ATPase gene; Bhattacharjee H et al.; The plasmid encoded ArsA ATPase in Escherichia coli is the catalytic component of an oxyanion pump that is responsible for resistance to arsenicals and antimonials . Arsenite or antimonite allosterically activates the ArsA ATPase activity . In this paper, we report the cloning and characterization of the mouse homologue (Asna1) of the bacterial arsA gene . The Asna1 gene encodes an open reading frame of 348 amino acids and exhibits 27% identity to the bacterial ArsA protein and 99% similarity to its human counterpart (hASNA-1) . The Asna1 mRNA is a approximately 1.3 kb transcript and is present at high levels in kidney and testis, moderate levels in brain, liver, lung and skin, and low levels in heart, small intestine, spleen, stomach, and thymus . A negligible amount of Asna1 transcript is detected in skeletal muscle . We have also characterized the genomic structure of the Asna1 gene . The gene spans over 7 kb and consists of seven exons and six introns . All splice sites conform to the GT-AG rule, except for the splice donor site of intron 4 that is GC instead of GT . Fluorescence in situ hybridization indicates that the Asna1 gene is localized in the C3-D1 region of mouse chromosome 8. Blood, 2001 Aug 1, 98(3), 736 - 42 Type I interferons in combination with bacterial stimuli induce apoptosis of monocyte-derived dendritic cells; Lehner M et al.; Both type I interferons (IFNs) as well as lipopolysaccharide (LPS) individually compromise selected monocytic or dendritic cell (DC) functions . This study investigates the influence of these agents on the differentiation and the regulation of cell death of monocyte-derived DCs generated in the presence of granulocyte-macrophage colony-stimulating factor plus interleukin-4 (IL-4) . It is reported that excessive apoptosis occurred rapidly in monocyte-derived DC cultures, if IFN-alpha or IFN-beta was added in combination with LPS or lipoteichoic acid (LTA) . The small fraction of cells surviving in such cultures displayed a mature DC phenotype with expression of CD83, CD80, and CD86 . IL-10 was found in the supernatants of monocyte-derived DC cultures, if supplemented with LPS or IFN-alpha plus LPS but not in control cultures . When monocyte-derived DCs were generated in the presence of IFN-alpha without LPS, these cells displayed an immature DC phenotype with a reduction of cell recovery but no overt apoptosis . However, the addition of LPS, LTA, LPS plus IFN-gamma, or tumor necrosis factor alpha (TNF-alpha) plus prostaglandin E2 to such cells again resulted in the rapid induction of apoptosis in the majority of cells, together with a reduced production of IL-12 p70 and TNF-alpha . Together, these data indicate an exquisite sensitivity of monocyte-derived DCs to activation-induced cell death if generated in the presence of IFN-alpha, indicating the existence of an important mechanism of immunosuppression caused by IFN-alpha-inducing agents, such as viral or bacterial stimuli . (Blood . 2001;98:736-742) Brief Bioinform, 2000 Nov, 1(4), 357 - 71 Comparative analysis of regulatory patterns in bacterial genomes; Gelfand MS et al.; Recognition of transcription regulatory sites in bacterial genomes is a notoriously difficult problem.There are no algorithms capable of making reliable predictions even for well-studied sites such as the CRP (cyclic AMP receptor protein) box . However, availability of complete bacterial genomes makes it possible to make reliable predictions with bad rules.This comparative approach is based on the assumption that sets of co-regulated genes are conserved in related bacteria.Thus true sites occur upstream of orthologous genes, whereas false candidates are scattered at random . This means not only that knowledge about regulation in well-studied genomes can be transferred to newly sequenced ones, but also that new members of regulons can be found.This paper reviews several recent studies . In particular, a detailed analysis of catabolite repression in gamma-purple bacteria is presented. Phys Rev E Stat Nonlin Soft Matter Phys . 2001 Jul;64(1 Pt 1):011902 . Epub 2001 Jun 12. Active and passive particles: modeling beads in a bacterial bath; Gregoire G et al.; A simple model for the motion of passive particles in a bath of active, self-propelled ones is introduced . It is argued that this approach provides the correct framework within which to cast the recent experimental results obtained by Wu and Libchaber {Phys Rev . Lett . 84, 3017 (2000)} for the diffusive properties of polystyrene beads displaced by bacteria suspended in a two-dimensional fluid film . Our results suggest that superdiffusive behavior should indeed be generically observed in the transition region marking the onset of collective motion. Transplantation, 2001 Jun 27, 71(12), 1840 - 7 Increased endothelin-1 associated with bacterial infection in lung transplant recipients; Charpin JM et al.; BACKGROUND: Endothelin-1 (ET-1) has fibrogenic and inflammatory properties . Its pathogenic role in pulmonary fibrosis and certain inflammatory airway diseases is now well known . Its production is, in part, triggered by infectious processes . Episodes of infection are suspected to be involved in the development of bronchiolitis obliterans syndrome (BOS), which is the main feature of chronic lung rejection and the major factor limiting the long-term survival of transplanted patients . We postulated that ET-1 is upregulated during infectious complications arising from the graft and that this could partly explain the remodeling of airway structures observed in BOS . We, therefore, set up this study to assess ET-1 expression in relation to complications of the graft in human lung transplant recipients . METHODS: ET-1 mRNA was quantified by reverse transcription-competitive polymerase chain reaction in cells from 119 samples of bronchoalveolar lavage (BAL) fluid from 17 lung transplant recipients . ET-1 and big ET-1 proteins were assessed in BAL cell culture supernatants by enzyme immunoassay . Transbronchial biopsies (n=21) were stained immunohistochemically for ET-1 receptors . RESULTS: Episodes of bacterial infection strongly correlated with increased ET-1 mRNA and protein expression . ET-1 receptors were also upregulated during these episodes, especially on endothelial and smooth muscle cells . Five of the seven patients with the highest ET-1 levels subsequently developed BOS . CONCLUSIONS: These results raise the possibility that ET-1, part of whose production is triggered by infectious postgraft complications, might play a role in the development of BOS through its potential effects on airway remodeling. J Clin Oncol, 2001 Jul 15, 19(14), 3415 - 21 Prospective, multicenter evaluation of risk factors associated with invasive bacterial infection in children with cancer, neutropenia, and fever; Santolaya ME et al.; PURPOSE: To identify clinical and laboratory parameters present at the time of a first evaluation that could help predict which children with cancer, fever, and neutropenia were at high risk or low risk for an invasive bacterial infection . PATIENTS AND METHODS: Over a 17-month period, all children with cancer, fever, and neutropenia admitted to five hospitals in Santiago, Chile, were enrolled onto a prospective protocol . Associations between admission parameters and risk for invasive bacterial infection were assessed by univariate and logistic regression analyses . RESULTS: A total of 447 febrile neutropenic episodes occurred in 257 children . Five parameters were statistically independent risk factors for an invasive bacterial infection . Ranked by order of significance, they were as follows: C-reactive protein levels of 90 mg/L or higher (relative risk {RR}, 4.2; 95% confidence interval {CI}, 3.6 to 4.8); presence of hypotension (RR, 2.7; 95% CI, 2.3 to 3.2); relapse of leukemia as cancer type (RR, 1.8, 95% CI, 1.7 to 2.3); platelet count less than or equal to 50,000/mm(3) (RR, 1.7; 95% CI, 1.4 to 2.2); and recent (< or = 7 days) chemotherapy (RR, 1.3; 95% CI, 1.1 to 1.6) . Other previously postulated risk factors (magnitude of fever, monocyte count) were not independent risk factors in this study population . CONCLUSION: In a large population of children, common clinical and laboratory admission parameters were identified that can help predict the risk for an invasive bacterial infection . These results encourage the possibility of a more selective management strategy for these children. Mol Microbiol, 2001 Jul, 41(1), 241 - 6 Transport of cytochrome c derivatives by the bacterial Tat protein translocation system; Sanders C et al.; An experimental system developed previously for the heterologous expression of c-type cytochromes in Escherichia coli Q1has been adapted to monitor protein transfer across the bacteria's cytoplasmic membrane . Apocytochrome, lacking the haem cofactor and probably in an unfolded state, was readily transferred across the cytoplasmic membrane when fused to a Sec-specific signal peptide . Furthermore, cytochrome fused to a signal peptide regarded as specific for the twin arginine transport (Tat) system was translocated in an unfolded state by the Sec apparatus . After maturation and folding in the cytoplasm, Tat-mediated transfer of holocytochrome to the periplasm occurred . We conclude that, in addition to the nature of the specific signal peptide, the folding state of a particular protein also governs its acceptance by a given transport system. Biochem Biophys Res Commun, 2001 Jul 20, 285(3), 800 - 5 The bacterial nucleoside N(6)-methyldeoxyadenosine induces the differentiation of mammalian tumor cells; Ratel D et al.; Contrary to bacterial DNA, mammalian DNA contains very little if any N(6)-methyldeoxyadenosine (MDA) . The possible biological effect of this nucleoside on eukaryotic cells has been studied on different tumor cell lines . Addition of MDA to C6.9 glioma cells triggers a differentiation process and the expression of the oligodendroglial marker 2',3'-cyclic nucleotide 3'phosphorylase (CNP) . The biological effects of N(6)-methyldeoxyadenosine were not restricted to C6.9 glioma cells since differentiation was also observed on pheochromocytoma and teratocarcinoma cell lines and on dysembryoplastic neuroepithelial tumor cells . The precise mechanism by which MDA induces cell differentiation remains unclear, but is related to cell cycle modifications . These data point out the potential interest of N(6)-methyldeoxyadenosine as a novel antitumoral and differentiation agent . They also raise the intriguing question of the loss of adenine methylation in mammalian DNA . Furthermore, the finding that a methylated nucleoside found in bacterial DNA induces a biological process might have implications in gene therapy approaches when plasmid DNAs are injected into humans . Mikrobiologiia, 2001 May-Jun, 70(3), 352 - 9 {Characteristics of infection of plants and their cultured tissue with cyanobacterial-bacterial symbiotic associations}; Lobakova ES et al.; The infection of tobacco, nightshade, rice plants, and their tissue cultures with the cyanobacteria-bacteria symbiotic associations (CBSA) isolated from natural syncyanoses (the ferns Azolla pinnata and Azolla sp . and the cycad Encephalartos ferox) was studied . The inoculation of the intact plants or their cuttings with CBSA led to the colonization of the plant roots, stems, and leaves by cyanobacteria and their bacterial symbionts (referred to as satellite bacteria, SB) . The sites of the long-term contact of plant organs with cyanobacteria were characterized by the formation of copious slime . On the roots of infected plants, one could observe the callus growth of cortical parenchyma cells and the formation of pseudonodules, in which SB cells gradually accumulated . In mixed cultures of plant callus tissues and the CBSA isolated from the ferns A . pinnata and Azolla sp., the callus tissue specifically influenced the growth of the CBSA components, causing (depending on the plant species and strain) either their balanced growth, or their cyclic growth, or the predominant growth of one of the CBSA components (either cyanobacteria or satellite bacteria) . This phenomenon is proposed to be used for the dissociation of stable multicomponent natural symbiotic complexes and the selection of their particular components. Przegl Lek, 2001, 58(4), 348 - 50 The bacterial flora and the changes of the N-nitrosamine concentration in the operated stomach; Kopanski Z et al.; The studies included 170 patients (103 men and 67 women) aged 23 to 66 years, operated on because of an ulcerous disease . Depending on the method of surgical treatment patients were divided into 5 groups (those after gastric resection with Rydygier's method, after resection with the Billroth II method, after trunk vagotomy with pyloroplasty, after highly selective vagotomy, and after gastro-enterostomy) . In all patients a qualitative estimation of the nitrate-reducing bacteria was carried out, as well as a chromatographic test of the selected N-nitrosamine concentration in the gastric juice . It was shown that the changes in the quantity of the nitrate-reducing bacteria and in the N-nitrosamine concentration depended on the type of surgical intervention conducted . The largest mean content of nitrate-reducing bacteria and the highest average N-nitrosamine concentration were confirmed in the gastric juice of patients after gastroenterostomy and after gastric resection with the Billroth II method, and the lowest values--in patients after highly selective vagotomy. J Hered, 2001 May-Jun, 92(3), 267 - 70 Molecular mapping of Rxp conditioning reaction to bacterial pustule in soybean; Narvel JM et al.; The Rxp locus in soybean {Glycine max (L.) Merr.} that conditions reaction to bacterial pustule was mapped by simple sequence repeat (SSR) marker analysis . A population of 116 F4-derived lines from a cross between the resistant parent Young and the susceptible parent PI 416937 was used for mapping . The Rxp locus was mapped 3.9 cM from Satt372 and 12.4 cM from Satt014 on linkage group D2 . Linkage associations were confirmed by identifying a close association between the SSR genotype at each locus identified as flanking Rxp and the bacterial pustule reaction of individual lines derived from a population different from the one used for mapping . A molecular pedigree analysis showed that bacterial pustule-resistant cultivars inherited the resistance gene rxp from the ancestral cultivar CNS based on their consistent genotypic pattern at flanking marker loci . Based on the results of the study, marker-assisted selection for rxp would be very effective. Toxicol Appl Pharmacol, 2001 Jul 15, 174(2), 113 - 21 Involvement of cyclooxygenase-2 in the potentiation of allyl alcohol-induced liver injury by bacterial lipopolysaccharide; Ganey PE et al.; Bacterial endotoxin (lipopolysaccharide; LPS) augments the hepatotoxicity of a number of xenobiotics including allyl alcohol . The mechanism for this effect is known to involve the inflammatory response elicited by LPS . Upregulation of cyclooxygenase-2 (COX-2) and production of eicosanoids are important aspects of inflammation, therefore studies were undertaken to investigate the role of COX-2 in LPS-induced enhancement of liver injury from allyl alcohol . Rats were pretreated (iv) with a noninjurious dose of LPS or sterile saline vehicle and 2 h later were treated (ip) with a noninjurious dose of allyl alcohol or saline vehicle . COX-2 mRNA was determined by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR), and liver injury was assessed from activities in serum of alanine and aspartate aminotransferases (ALT and AST, respectively) and from histology . Liver injury was observed only in rats cotreated with LPS and allyl alcohol . Serum ALT activity was increased by 4 h after administration of LPS and continued to increase through 8 h . COX-2 mRNA was detectable at low levels in livers from rats receiving only the vehicles at any time up to 8 h . Expression of COX-2 mRNA was increased by 30 min after administration of LPS and remained elevated through 6 h . Allyl alcohol treatment alone caused an increase in COX-2 mRNA at 4 h (2 h after allyl alcohol) that lasted less than 2 h . In livers from rats cotreated with LPS and allyl alcohol, levels of COX-2 mRNA were greater than levels seen with either LPS or allyl alcohol alone . The increased expression of COX-2 mRNA was accompanied by an increase in the concentration of prostaglandin (PG) D(2) in plasma . Plasma PGD(2) concentration was increased to a greater extent in rats treated with LPS plus allyl alcohol compared to allyl alcohol or LPS alone . Pretreatment with the COX-2 selective inhibitor, NS-398, abolished the increase in plasma PGD(2) and reduced the increase in ALT and AST activities observed in rats cotreated with LPS and allyl alcohol . NS-398 did not affect liver injury from allyl alcohol alone administered at a larger, hepatotoxic dose . In addition, ibuprofen, a nonselective inhibitor of cyclooxygenases, did not protect against liver injury from LPS plus allyl alcohol . In isolated hepatocytes PGD(2), but not PGE(2), reduced the concentration of allyl alcohol required to cause half-maximal cytotoxicity . These results suggest that products of COX-2 play a role in the augmentation of allyl alcohol-induced liver injury by LPS . Ann Hematol, 2001 May, 80(5), 278 - 83 Human peripheral blood mononuclear cells require factor X and platelets for expression of prothrombinase activity in response to bacterial lipopolysaccharide; Pejler G et al.; We investigated whether human peripheral blood mononuclear cells (PBMC) express prothrombinase following stimulation with bacterial lipopolysaccharide (LPS) . LPS-stimulated PBMC devoid of contaminating platelets failed to activate prothrombin directly . Addition of platelets did not result in expression of prothrombinase in the absence of factor X whereas the combination of platelets and factor X resulted in strong prothrombinase activity on LPS-activated cells . The induced prothrombinase was dependent on tissue factor, as the activity was completely inhibited by an anti-tissue factor antibody . Our data suggest that platelet/monocyte cooperation is important in the generation of prothrombinase activity in response to endotoxin. Res Microbiol, 2001 Jun, 152(5), 431 - 7 Intracellular bacterial symbiosis in the genus Sitophilus: the 'biological individual' concept revisited; Heddi A et al.; Eukaryotic cells, as genetic entities, most often involve several physically associated genomes that direct the metabolic cell equilibrium . In the coleopteran insects of the genus Sitophilus, in addition to the nucleus and the mitochondrial genomes, two other intracellular bacterial genomes belonging to the alpha and the gamma groups of Proteobacteria are also present . Coexisting with the eukaryotic host cell genomes, they intervene in the physiology and reproduction of the host . They are both transmitted vertically to the progeny and exhibit different levels of symbiont integration in insects . Their coexistence within a eukaryotic cell system illustrates the genetic complexity of animal tissue and questions the concept of the 'biological individual'. Biochem Biophys Res Commun, 2001 Jul 13, 285(2), 550 - 4 Effect of two polyamine toxins on the bacterial porin OmpF; Basle A et al.; Spermine, a polyamine based on a 12-carbon motif, is an effective inhibitor of E . coli OmpF porin . Here we study the inhibition of porin by two polyamine toxins commonly used as modulators of polyamine-sensitive channels: Philanthotoxin-433 (PhTX) from wasp venom and Joro spider toxin (JSTX) . Both are highly asymmetric molecules, with at one end a 12-carbon chain polyamine targeting the molecule to the porin constriction zone, and at the other end large aromatic groups conferring to this extremity a size in the order of the OmpF constriction zone . Here we report that PhTX, but not Joro toxin, induces a high degree of flickering in the OmpF-mediated current . The effect is concentration and voltage-dependent, and greatly diminished in a mutant lacking D113 on the constriction loop, a residue previously shown to be required for spermine sensitivity . Possible reasons for the distinct sensitivity of OmpF to PhTX and Joro toxin are discussed . Genome, 2001 Jun, 44(3), 463 - 9 Instability of bacterial artificial chromosome (BAC) clones containing tandemly repeated DNA sequences; Song J et al.; The cloning and propagation of large DNA fragments as bacterial artificial chromosomes (BACs) has become a valuable technique in genome research . BAC clones are highly stable in the host, Escherichia coli, a major advantage over yeast artificial chromosomes (YACs) in which recombination-induced instability is a major drawback . Here we report that BAC clones containing tandemly repeated DNA elements are not stable and can undergo drastic deletions during routine library maintenance and DNA preparation . Instability was observed in three BAC clones from sorghum, rice, and potato, each containing distinct tandem repeats . As many as 46% and 74% of the single colonies derived from a rice BAC clone containing 5S ribosomal RNA genes had insert deletions after 24 and 120 h of growth, respectively . We also demonstrated that BAC insert rearrangement can occur in the early stage of library construction and duplication . Thus, a minimum growth approach may not avoid the instability problem of such clones . The impact of BAC instability on genome research is discussed. Genome, 2001 Jun, 44(3), 382 - 93 Construction of a 1.2-Mb contig including the citrus tristeza virus resistance gene locus using a bacterial artificial chromosome library of Poncirus trifoliata (L.) Raf; Yang ZN et al.; The citrus tristeza virus resistance gene (Ctv) is a single dominant gene in Poncirus trifoliata, a sexually compatible relative of citrus . To clone this gene, a bacterial artificial chromosome (BAC) library has been constructed from an individual plant that was homozygous for Ctv . This library contains 45,696 clones with an average insert size of 80 kb, corresponding to 9.6 genome equivalents . Screening of the BAC library with five chloroplast DNA probes indicated that 0.58% of the BAC clones contained chloroplast-derived inserts . The chromosome walk across the Ctv locus was initiated using three closely linked genetic markers: C19, AD8, and Z16 . The walk has been completed and a contig of ca . 1.2 Mb was constructed . Based on new data, the genetic map in the Ctv region was revised, with Ctv being located between AD8-Z16 and C19 at distances of 1.2 and 0.6 cM, respectively . Utilizing DNA fragments isolated from the contig as RFLP markers, the Ctv locus was further mapped to a region of ca . 300 kb . This contig contains several putative disease-resistance genes similar to the rice Xa21 gene, the tomato Cf-2 gene, and the Arabidopsis thaliana RPS2 gene . This library will therefore allow cloning of Ctv and other putative disease-resistance genes. Acta Paediatr, 2001 Jun, 90(6), 611 - 7 Prediction of bacterial meningitis in children with meningeal signs: reduction of lumbar punctures; Oostenbrink R et al.; Physicians often have to perform a lumbar puncture to ascertain the diagnosis in patients with meningeal signs, because of the serious consequences of missing bacterial meningitis . The aim of this study was to derive and validate a clinical rule to predict bacterial meningitis in children with meningeal signs, to guide decisions on the performance of lumbar punctures . Information was collected from records of patients (aged 1 mo to 15 y) consulting the emergency department of the Sophia Children's Hospital between 1988 and 1998 with meningeal signs . Bacterial meningitis was defined as cerebrospinal fluid (CSF) leucocyte count >5 cells microl(-1) with a positive bacterial culture of CSF or blood . The diagnostic value of predictors was judged using multivariate logistic modelling and area under the receiver operating characteristic curves (ROC area) . In the derivation set (286 patients, years 1988-1995) the duration of the main complaint, vomiting, meningeal irritation, cyanosis, petechiae and disturbed consciousness were independent clinical predictors of bacterial meningitis . The ROC area of this model was 0.92 . The only independent predictor from subsequent laboratory tests was the serum C-reactive protein concentration, increasing the ROC area to 0.95 . Without missing a single case, this final model identified 99 patients (35%) without bacterial meningitis . Validation on 74 consecutive patients in 3 subsequent years (1996-1998) yielded similar results . Conclusion: This prediction rule identifies about 35% of the patients with meningeal signs in whom a lumbar puncture can be withheld without missing a single case of bacterial meningitis . For the individual patient this prediction rule is valuable in deciding whether or not to perform a lumbar puncture. Clin Infect Dis, 2001 Aug 1, 33(3), 406 - 8 Epub 2001 Jun 21. Lack of sensitivity of the latex agglutination test to detect bacterial antigen in the cerebrospinal fluid of patients with culture-negative meningitis; Tarafdar K et al.; For culture-negative meningitis, use of the latex agglutination test for detection of bacterial antigen in the CSF has a sensitivity of only 7% . Routine use of the latex agglutination test may not contribute to the management of suspected acute bacterial meningitis, since patients are treated on the basis of their clinical presentations and CSF findings. Pediatr Emerg Care, 2001 Jun, 17(3), 161 - 4 Signs of meningeal irritation at the emergency department: how often bacterial meningitis? Oostenbrink R, Moons KG, Theunissen CC, Derksen-Lubsen G, Grobbee DE, Moll HA. OBJECTIVE: Although signs of meningeal irritation are highly indicative of meningitis, they are not pathognomonic . In this study, we described the final diagnoses in children with signs of meningeal irritation, and we assessed the frequency of bacterial meningitis related to specific signs of meningeal irritation . METHODS: Information was collected from records of 326 patients (aged 1 month to 15 years) who visited the emergency department of the Sophia Children's Hospital between 1988 and 1998 with signs of meningeal irritation, assessed by either the general practitioner or the pediatrician . RESULTS: Bacterial meningitis was diagnosed in 99 patients (30%), viral or aseptic meningitis in 43 (13%) . Other diagnoses were pneumonia (8%), other serious bacterial infections (2%), and upper respiratory tract infections or other self-limiting diseases (46 %) . Presence of one of the signs of meningeal irritation assessed by the pediatrician was related to bacterial meningitis in 39% . Specific tests eliciting meningeal irritation, such as Brudzinski's and Kernig's signs, were not related to a higher frequency of bacterial meningitis than neck stiffness and the tripod phenomenon . In children < or =1 year, bacterial meningitis is more frequently related to presence of irritability and a bulging fontanel . CONCLUSION: Bacterial meningitis is present in 30% of children with signs of meningeal irritation . Presence of meningeal irritation as assessed by the pediatrician is related to bacterial meningitis in 39% . A better prediction of bacterial meningitis was not achieved by using more specific tests for signs of meningeal irritation. Kidney Blood Press Res, 2001, 24(2), 105 - 10 Absence of cytokine response to bacterial challenge in human tubuloepithelial cells; Leeker A et al.; In acute bacterial renal infections, which are most frequently caused by Escherichia coli, tubuloepithelial cells are involved with respect to bacterial adherence, invasion and cytotoxicity . In addition, cytokines expressed by tubuloepithelial cells may be relevant for the recruitment of inflammatory cells and tissue damage in bacterial interstitial nephritis . We asked which inflammatory cytokines are produced by primary human tubuloepithelial cells following in vitro exposure to E . coli and found no release of IL-6, IL-8 and TNF-alpha by tubular cells challenged by bacteria . Purified virulence factors (fimbriae, lipopolysaccharide) from E . coli were also without effects on cytokine release by tubular cells . Since lymphocytic infiltration is a characteristic feature in the chronic form of interstitial nephritis, MHC class II expression by tubular cells in response to bacterial coincubation was analyzed . Exposure to both IFN-gamma and E . coli enhanced MHC class II expression on tubuloepithelial cells . In conclusion, tubuloepithelial cells may play an active role in the local defense against bacteria, e.g . by expressing MHC class II molecules . However, in vitro inflammatory cytokines are not induced by E . coli in this cell population. Trends Microbiol, 2001 Jul, 9(7), 302 - 7; discussion 308 An abundance of bacterial ADP-ribosyltransferases--implications for the origin of exotoxins and their human homologues; Pallen MJ et al.; ADP-ribosylation is a post-translational modification that can be seen in many contexts, including as the primary mechanism of action of many important bacterial exotoxins . By data-mining complete and incomplete bacterial genome sequences, we have discovered >20 novel putative ADP-ribosyltransferases, including several new potential toxins. Int Immunol, 2001 Jul, 13(7), 933 - 40 Discrimination of bacterial lipoproteins by Toll-like receptor 6; Takeuchi O et al.; Bacterial lipoproteins (BLP) trigger immune responses via Toll-like receptor 2 (TLR2) and their immunostimulatory properties are attributed to the presence of a lipoylated N-terminus . Most BLP are triacylated at the N-terminus cysteine residue, but mycoplasmal macrophage-activating lipopeptide-2 kD (MALP-2) is only diacylated . Here we show that TLR6-deficient (TLR6(-/-)) cells are unresponsive to MALP-2 but retain their normal responses to lipopeptides of other bacterial origins . Reconstitution experiments in TLR2(-/-) TLR6(-/-) embryonic fibroblasts reveal that co-expression of TLR2 and TLR6 is absolutely required for MALP-2 responsiveness . Taken together, these results show that TLR6 recognizes MALP-2 cooperatively with TLR2, and appears to discriminate between the N-terminal lipoylated structures of MALP-2 and lipopeptides derived from other bacteria. Cytometry, 2001 Jul 1, 44(3), 188 - 94 Using light scatter signal to estimate bacterial biovolume by flow cytometry; Bouvier T et al.; BACKGROUND: In the past decade, flow cytometry has become a useful and precise alternative to microscopic bacterial cell counts in aquatic samples . However, little evidence of its usefulness for the evaluation of bacterial biovolumes has emerged in from the literature . METHODS: The light scattering and cell volume of starved bacterial strains and natural bacterial communities from the Black Sea were measured by flow cytometry and epifluorescence microscopy, respectively, in order to establish a relationship between light scattering and cell volume . RESULTS: With the arc-lamp flow cytometer, forward angle light scatter (FALS) was related to cell size in both the starved strains and natural communities, although regression parameters differed . We tested the predictive capacity of the FALS verous cell size relationship in a bacterial community from the North Sea . That analysis showed that a reliable bacterial biovolume prediction of a natural bacterial community can be obtained from FALS using a model generated from natural bacterial community data . CONCLUSIONS: Bacterial biovolume is likely to be related to FALS measurements . It is possible to establish a generally applicable model derived from natural bacterial assemblages for flow cytometric estimation of bacterial biovolumes by light scatter . Appl Environ Microbiol, 2001 Jul, 67(7), 2916 - 21 The leucine incorporation method estimates bacterial growth equally well in both oxic and anoxic lake waters; Bastviken D et al.; Bacterial biomass production is often estimated from incorporation of radioactively labeled leucine into protein, in both oxic and anoxic waters and sediments . However, the validity of the method in anoxic environments has so far not been tested . We compared the leucine incorporation of bacterial assemblages growing in oxic and anoxic waters from three lakes differing in nutrient and humic contents . The method was modified to avoid O(2) contamination by performing the incubation in syringes . Isotope saturation levels in oxic and anoxic waters were determined, and leucine incorporation rates were compared to microscopically observed bacterial growth . Finally, we evaluated the effects of O(2) contamination during incubation with leucine, as well as the potential effects of a headspace in the incubation vessel . Isotope saturation occurred at a leucine concentration of above about 50 nM in both oxic and anoxic waters from all three lakes . Leucine incorporation rates were linearly correlated to observed growth, and there was no significant difference between oxic and anoxic conditions . O(2) contamination of anoxic water during 1-h incubations with leucine had no detectable impact on the incorporation rate, while a headspace in the incubation vessel caused leucine incorporation to increase in both anoxic and O(2)-contaminated samples . The results indicate that the leucine incorporation method relates equally to bacterial growth rates under oxic and anoxic conditions and that incubation should be performed without a headspace. J Gastroenterol Hepatol, 2001 Jun, 16(6), 607 - 12 Intestinal dysfunction in liver cirrhosis: Its role in spontaneous bacterial peritonitis; Ramachandran A et al.; Spontaneous bacterial peritonitis is a common illness in patients with cirrhosis and ascites that occurs without any apparent focus of infection . Bacterial translocation plays an important role in spontaneous bacterial peritonitis and it is evident from a variety of studies that the gut is a major source of this bacteria . Gut motility alterations, along with bacterial overgrowth and changes in intestinal permeability, probably play a role in this bacterial translocation . The present review looks at the role of the intestine in spontaneous bacterial peritonitis induced by liver cirrhosis and the factors influencing bacterial translocation in this disease. Res Microbiol, 2001 Apr-May, 152(3-4), 259 - 70 Bacterial ABC transporters of amino acids; Hosie AH et al.; There are two subfamilies of ABC uptake systems for amino acids in bacteria, the polar amino acid transport family and the hydrophobic amino acid transport family . We consider the general properties of these families and we examine the specific transporters . Focusing on some of the best-studied ATP binding cassette transporters we also examine the mechanism of amino acid uptake, paying particular attention to the question of bidirectionality of solute movement. Trends Genet, 2001 Jul, 17(7), 365 - 70 Polyphyletic origins of bacterial Nramp transporters; Cellier MF et al.; The redox-active metals iron and manganese are required for energy metabolism, protection against oxidative stress and defense against infections . In eukaryotes, both divalent metals are transported by Nramp transporters . The sequence of these transporters was remarkably conserved during evolution . Several bacterial Nramp homologs (MntH) are also proton-dependent manganese transporters . Here, we present phylogenetic evidence for the polyphyletic origins of three groups of MntH proteins and for possible Nramp horizontal gene transfer with eukaryotes . We propose that the evolution of the MntH/Nramp family is related to adaptation to oxidative environments, including those arising during infection of animals and plants. Inflamm Res, 2001 May, 50(5), 254 - 61 The inflammatory response in humans after inhalation of bacterial endotoxin: a review; Thorn J; There is increasing evidence that diseases caused by organic dusts are mainly of an inflammatory nature . Among the many agents present in organic dusts, bacterial endotoxin is a major candidate for the inflammatory reaction . The purpose of this paper was to review the inflammatory response in humans after inhalation of bacterial endotoxin (lipopolysaccharide, LPS) in order to improve the understanding of symptoms and reactions found among persons exposed to endotoxin-containing organic dusts . It has been reported that inhalation of LPS causes changes in forced expiratory volume in one second (FEV1), and forced vital capacity (FVC) . At the alveolar level, inhalation of LPS can induce changes in the diffusion capacity . Activation and migration of neutrophils are major effects of acute LPS inhalation . Changes in mediators of inflammation, such as eosinophilic cationic protein (ECP), myeloperoxidase (MPO), interleukin-8 (IL-8), IL-1beta, tumor necrosis factor alpha (TNFalpha) and C-reactive protein (CRP) in the airways and/or blood, have also been found . Inhalation of 30-40 microg LPS seems to be a threshold level for inducing clinical symptoms and lung function changes in healthy subjects . The threshold dose for inducing changes in blood neutrophils may be less than 0.5 microg LPS . In conclusion, available data regarding the responses to LPS inhalation challenges demonstrate a local and a systemic inflammatory response at lower doses of LPS, while higher inhaled doses are required to elicit significant clinical and lung function responses . Future inhalation studies on LPS need to focus on relevant diagnostic tools for the inflammatory reaction among persons exposed to endotoxin-containing organic dusts and to evaluate whether the large variation between individuals in the response to organic dusts or endotoxin could be due to differences in the molecular mechanisms responsible for the toxicity of the agent. Pediatr Surg Int, 2001 May, 17(4), 280 - 3 Tissue antioxidant capacity and bacterial translocation under total parenteral nutrition; Eizaguirre I et al.; Alterations in the antioxidative system have been observed during total parenteral nutrition (TPN) . Light exposure or changes in the composition of TPN formulas may affect this system . Bacterial translocation (BT) is frequent under TPN and may be related to oxidative status . The aim of this study was to determine the adverse effects of standard and glutamine-enriched TPN, with or without light exposure, on oxidative status (liver and kidney-reduced glutathione, GSH) and its relationship to BT . Thirty-three adult Wistar rats underwent central-venous cannulation and were randomly assigned to one of four groups receiving different TPN regimes for 10 days . The TPN group (n = 10) had standard TPN, the TPN(-) group (n = 8) standard TPN without light exposure, the GTPN group (n = 8) glutamine-enriched TPN, and the GTPN(-) group (n = 7) glutamine-enriched TPN without light exposure . A sham group (n = 16) receiving chow and water ad libitum and saline i.v . served as controls . At the end of the experiment, GSH was determined in liver and kidney tissue . Mesenteric lymph nodes and peripheral and portal blood samples were cultured for BT . Compared to sham rats, TPN groups had statistically significant lower GSH levels, but there were no differences between standard or glutamine-enriched groups or light-exposure groups . Sham animals had 12% BT . Significantly higher BT (P < 0.05) occurred in TPN rats: 70% in the TPN group, 88% in the TPN(-) group, 86% in GTPN (-) animals, and only 50% in the GTPN group (P = 0.06 vs TPN group) . In conclusion, (1) TPN reduces antioxidant capacity; (2) glutamine supplementation or light protection does not improve tissue antioxidant capacity under TPN; (3) the absence of light exposure does not improve TPN-related BT; and (4) glutamine supplementation tends to reduce BT only in the presence of light. Pediatr Surg Int, 2001 May, 17(4), 275 - 9 Effect of secretory immunoglobulin A on bacterial translocation in an enterocyte-lymphocyte co-culture model; Sawai T et al.; Intestinal secretory immunoglobulin A (sIgA) plays an important role in gut mucosal immunity in vivo; however, in-vitro enterocyte models for studying the mechanisms of these effects are lacking . This study utilizes a cell-culture model to investigate the effect of sIgA on bacterial translocation (BT) across human enterocytes co-cultured with human lymphoid cells (Raji cells) . This model is intended to mimic in-vivo enterocyte/lymphocyte interactions found in intestinal follicle-associated epithelia . Human Caco-2 enterocytes were grown to confluence on porous filters in the apical chamber of a two-chamber cell-culture system . After differentiation, human B lymphoid cells (Raji cells) were added to the basolateral surface of Caco-2 monolayers for 3 days' co-culture, followed by washing away of unincorporated Raji cells . Transepithelial electrical resistance (TEER) was used to measure tight-junction permeability . Monolayers were treated with or without sIgA, IgG (negative control), or mannose (positive control) . BT across the cell monolayer was determined 1.5 h after addition of Escherichia coli . Statistical analysis was by the Kruskal-Wallis test, P below 0.05 considered significant . In co-culture monolayers treated with sIgA, IgG, or mannose, there was no significant effect on TEER; however, the magnitude of BT across cells treated with sIgA (1.3 +/- 0.4 log10CFU/ml) and mannose (1.6 +/- 1.1 log10CFU/ml) was significantly decreased compared to PBS (3.9 +/- 0.4 log10CFU/ml) and IgG (2.9 +/- 0.6 log10CFU/ml) controls (P < 0.05) . sIgA BT inhibition was dose-dependent . BT inhibition by sIgA and mannose was additive (0.5 +/- 1 log10CFU/ml) . Inhibition of BT was negated when sIgA and mannose were removed by washing prior to E . Coli addition (3.6 +/- 0.5 log10CFU/ml), suggesting that both inhibitors act through bacterial binding. Pediatr Surg Int, 2001 May, 17(4), 269 - 74 The effect of phospholipids and fatty acids on tight-junction permeability and bacterial translocation; Sawai T et al.; The activity of phospholipase A2 (PLA2) is elevated in the intestinal epithelia of patients with inflammatory bowel disease (IBD) . We recently reported that PLA2 mediates hydrolysis of phosphatidylcholine (PC) to lysophosphatidylcholine (L-PC) when both are applied to the apical surface of cultured EC monolayers, resulting in increased bacterial translocation (BT) and decreased transepithelial electrical resistance (TEER) . Free fatty acids (FFA) are the other products of this reaction, however, their effect on Caco-2 cell permeability has not been reported . In addition to PC, other luminal phospholipids are present at the surface of the enterocyte . PLA2 may also mediate the hydrolysis of luminal phospholipids other than PC . The aim of this study was to examine the effects of phospholipids other than PC and common FFA on intestinal epithelial permeability and BT . Human Caco-2 enterocytes were grown to confluence on porous filters in the apical chamber of a two-chamber cell-culture system . Monolayer integrity and tight-junction permeability were measured as TEER . First, common FFA released by PC hydrolysis were determined using thin-layer chromatography (TLC) . In separate experiments, monolayers were treated with phosphatidylethanolamine (PE), lysophosphatidylethanolamine (L-PE), or palmitoleic acid, oleic acids, linoleic acids, and arachidonic acid solubilized in solution with PC . The magnitude of BT was determined 2 h after treatment by adding Escherichia coli C25 to the apical chamber followed by quantitatively culturing basal-chamber samples . Statistical analysis was by the Kurosaki-Wallis test . TLC of PC samples incubated with PLA2 on the apical surface of Caco-2 monolayers demonstrated the production of palmitoleic acid, oleic acids, linoleic acids, and arachidonic acid . L-PE significantly decreased TEER compared to controls, but to a lesser degree than L-PC alone . L-PE had no effects on BT . Palmitoleic acid and oleic acid likewise significantly decreased TEER compared to controls, however, less than L-PC . All FFA tested had no effect on BT . Phospholipids applied to the apical surface of enterocytes, such as those found in vivo in mucus, can be hydrolyzed by the enzyme PLA2 resulting in lysophospholipid and FFA species that can alter enterocyte monolayer permeability . However, FFA and L-PL, other than L-PC, appear to have no effect to stimulate BT . This observation may have clinical implications in the pathogenesis and treatment strategies for IBD patients in whom enterocyte PLA2 activity has been shown to be elevated. Immunology, 2001 Jun, 103(2), 226 - 34 The role of the macrophage scavenger receptor in immune stimulation by bacterial DNA and synthetic oligonucleotides; Zhu FG et al.; To assess the role of the macrophage scavenger receptor type A (SRA) in immune activation by CpG DNA, cytokine induction and DNA uptake were tested in vitro and in vivo using SRA knockout (SRA-/-) and wild type (WT) mice . As a source of CpG DNA, Escherichia coli DNA (EC DNA) and a 20-mer phosphorothioate oligodeoxynucleotide with two CpG motifs (CpG ODN) were used . In vitro, both EC DNA and the CpG ODN induced dose-dependent increases of interleukin (IL)-12 production by spleen cells and bone-marrow-derived macrophages (BMMPhi) from both SRA-/- and WT mice . The levels of cytokines produced by SRA-/- spleen cells and BMMPhi were similar to those of WT spleen cells and BMMPhi . When injected intravenously with CpG ODN and EC DNA, both SRA-/- and WT mice showed elevated serum levels of IL-12 . To investigate further the role of the SRA, flow cytometry and confocal microscopy were performed to examine the uptake of fluorescently labelled oligonucleotides . SRA-/- and WT BMMPhi showed similarity in the extent of uptake and distribution of oligonucleotides as assessed by these two techniques . Together, these findings indicate that, while the SRA may bind DNA, this receptor is not essential for the uptake of CpG DNA or its immunostimulatory activity. Int J Syst Evol Microbiol, 2001 May, 51(Pt 3), 945 - 53 Implications of alternative classifications and horizontal gene transfer for bacterial taxonomy; Young JM; Following the publication of the Approved Lists, there has been a tendency to regard all subsequent revisions of classification as providing improved nomenclature, to be accepted without question . This takes no account of the fact that such revisions may be based on one of three alternative concepts, phenetic, phylogenetic or polyphasic classification, sometimes leading to different, valid, but incompatible nomenclature, or that some investigations are based only on subsets of relevant taxa and on limited data, leading to incomplete and sometimes confusing revisions of nomenclature . The polyphasic approach to classification has widespread support, although there appears to be a tendency to allow comparative sequence analyses of 16S rDNA to determine classification contrary to the indications of other data . In some cases, classification is based solely on 16S rDNA data . Examples are considered . Consideration is given to the criteria by which taxa are circumscribed, particularly at the level of genus and species . It is suggested that there is a need for reconciliation of the criteria by which taxa at these levels are circumscribed . Recent studies demonstrating the widespread occurrence of horizontal gene transfer suggest that there is a need for caution in monophyletic interpretations, especially when these are based on the analysis of single sequences. Adolesc Med, 2001 Jun, 12(2), vi, 243 - 68 Bacterial skin infections in adolescents; Darmstadt GL; Bacterial skin infections are the single most common skin disorder for which pediatric patients seek care . This manuscript reviews the principles of skin infections and the most common and important bacterial skin infections in adolescents. Nippon Ganka Gakkai Zasshi, 2001 May, 105(5), 348 - 52 {A case of subacute bacterial endocarditis showing acute macular neuroretinopathy-like lesions}; Takiura K et al.; PURPOSE: We report one case of mimic fundus lesions with acute macular neuroretinopathy due to subacute bacterial endocarditis . CASE: A 55-year-old male had about a 1 DD reddish petal-shaped lesion at the level of the retinal pigment epithelium in the macula and a white lesion about 1/6 DD at the level of the retinal pigment epithelium in the upper fovea . Fluorescein angiography showed the reddish lesion to be hypofluorescence due to a filling defect and indocyanine green angiography showed the hypofluorescence was due to a circulatory disturbance of the choriocapillaris . Additionally, we found that there was a severe choroidal circulatory obstruction in the white lesion on the retinal pigment epithelium . After the disappearance of the white lesion, secondary retinal pigment epithelium atrophy remained . CONCLUSION: The macular lesions of acute macular neuroretinopathy were ischaemic lesions of the retinal pigment epithelium formed because of a disturbance at the level of the choriocapillaris. Syst Appl Microbiol, 2001 Apr, 24(1), 31 - 6 Effects of deflected droplet electrostatic cell sorting on the viability and exoproteolytic activity of bacterial cultures and marine bacterioplankton; Resina-Pelfort O et al.; The cell-sorting capability of flow cytometers makes it possible to isolate specific populations of cells with pre-defined cytometric characteristics . A better knowledge of the biological effects of the sorting process is necessary for the future cell sorting applications . In this paper we report the effects of flow cytometric sorting on bacterial viability and exoproteolytic activity (EPA) of bacterial cultures and marine bacterioplankton . Sorting bacterial cultures and bacterioplankton samples reduce viability as assessed by plate counts and produce variations in the exoproteolytic activity . These effects indicate that deflected electrostatic sorting may significantly alter the biological properties of the sorted bacteria. Infect Immun, 2001 Jul, 69(7), 4691 - 4 Francisella tularensis induces cytopathogenicity and apoptosis in murine macrophages via a mechanism that requires intracellular bacterial multiplication; Lai XH et al.; The murine macrophage-like cell line J774.A1 ingests and allows intracellular growth of Francisella tularensis . We demonstrate that, after 24 h of infection, a pronounced cytopathogenicity resulted and the J774 cells were undergoing apoptosis . Despite this host cell apoptosis, no decrease in bacterial numbers was observed . When internalization of bacteria was prevented or intracellularly located F . tularensis bacteria were eradicated within 12 h, the progression of host cell cytopathogenicity and apoptosis was prevented. Biochemistry, 2001 Jun 19, 40(24), 7109 - 16 Thermodynamics of electron transfer in oxygenic photosynthetic reaction centers: a pulsed photoacoustic study of electron transfer in photosystem I reveals a similarity to bacterial reaction centers in both volume change and entropy; Hou JM et al.; The thermodynamic properties of electron transfer in biological systems are far less known in comparison with that of their kinetics . In this paper the enthalpy and entropy of electron transfer in the purified photosystem I trimer complexes from Synechocystis sp . PCC 6803 have been studied, using pulsed time-resolved photoacoustics on the 1 micros time scale . The volume contraction of reaction centers of photosystem I, which results directly from the light-induced charge separation forming P(700+F(A)/F(B-) from the excited-state P700*, is determined to be -26 +/- 2 A3 . The enthalpy of the above electron-transfer reaction is found to be -0.39 +/- 0.1 eV . Photoacoustic estimation of the quantum yield of photochemistry in the purified photosystem I trimer complex showed it to be close to unity . Taking the free energy of the above reaction as the difference of their redox potentials in situ allows us to calculate an apparent entropy change (TDeltaS) of +0.35 +/- 0.1 eV . These values of DeltaV and TDeltaS are similar to those of bacterial reaction centers . The unexpected sign of entropy of electron transfer is tentatively assigned, as in the bacterial case, to the escape of counterions from the surface of the particles . The apparent entropy change of electron transfer in biological system is significant and cannot be neglected. Eur Respir J, 2001 Apr, 17(4), 636 - 40 Nosocomial bacterial pneumonia in human immunodeficiency virus infected subjects: incidence, risk factors and outcome; Tumbarello M et al.; The presented study examined the incidence, risk factors and outcome of nosocomial bacterial pneumonia (NBP) in human immunodeficiency virus (HIV)-infected subjects . Forty-two cases of NBP were ascertained by a 5-yr prospective surveillance and were matched to 84 controls . NBP incidence was 10.8 per 10,000 hospital patient-days . In particular, the incidence of NBP was 13.9 per 10,000 patient-days in the period 1994-1996 and 5.6 per 10,000 patient-days in the period 1997-1998 (p=0.01) . By using regression analysis, predictors for developing NBP were an increasing value of Acute Physiology and Chronic Health Evaluation (APACHE) III score (p<0.01) and the presence of acquired immune deficiency syndrome (AIDS)-related central nervous system (CNS) diseases (p=0.01) . The additional hospital stay attributable to NBP was 15 days . The attributable mortality rate was estimated to be 29% . Nosocomial bacterial pneumonia is more common in patients with advanced human immunodeficiency virus infection, high Acute Physiology and Chronic Health Evaluation III score and central nervous system diseases . Although the incidence of nosocomial bacterial pneumonia, as well of other opportunistic infections, decreased considerably in the era of highly active antiretroviral therapy, it still represents an important cause of mortality. Can J Microbiol, 2001 May, 47(5), 382 - 91 The effect of temperature on the fatty acids and isozymes of a psychrotrophic and two mesophilic species of Xenorhabdus, a bacterial symbiont of entomopathogenic nematodes; He H et al.; In the first part of this study, generation times relative to temperature, together with cardinal and conceptual temperatures, were determined for four strains of Xenorhabdus bacteria that represented three geographically distinct species . The data showed that the NF strain of Xenorhabdus bovienii, like the Umea strain of the same species, is psychrotrophic, while Xenorhabdus sp . TX strain resembles Xenorhabdus nematophila All strain in being mesophilic . In the second part, the capacity of these bacteria to adapt to changes in temperature, shown by changes in fatty acid composition, was investigated . As temperature declined, the proportions of the two major unsaturated fatty acids, palmitoleic (16:1omega7) acid and oleic (18:1omega9) acid, increased significantly in all of the strains . The proportion of the prevalent saturated fatty acid, which was palmitic acid (16:0), decreased . In the All, NF, and Umea strains, myristic acid (14:0), margaric acid (17:0), cyclopropane (17:0c), and arachidic acid (20:0) decreased with decreasing temperature . In the third part of the study, the synthesis of isozymes in response to changing temperature was investigated . For the seven enzymes studied, the numbers for which isozyme synthesis was temperature related were as follows: five for Umea, four for All, three for NF, and two for TX . Where the study dealt with fatty acid composition and isozyme synthesis, the results show a broad capacity for physiological temperature adaptation among strains of different climatic origin. Int J Food Sci Nutr, 2001 May, 52(3), 235 - 41 A simple bacterial turbidometric method for detection of S . aureus; Kumar JK et al.; A simple and rapid turbidometric method based on specificity of lysosotaphin to lyse S . aureus exclusively has been developed for detection of S . aureus contamination in foods. Semin Immunol, 2001 Jun, 13(3), 201 - 9 Understanding mucosal responsiveness: lessons from enteric bacterial pathogens; Simmons CP et al.; Mucosal immune responses must discriminate between commensal flora within the lumen and potential pathogens . These responses are highly adapted to induce protection without excessive inflammation . The balances that regulate mucosal immune and inflammatory responses have to be understood if effective mucosal immunity is to be induced through local immunization . This review will summarize some of the lessons learnt from studies of antigens derived from enteric bacterial pathogens and discuss how the gastrointestinal epithelia can 'fight back' when it encounters pathogens . Semin Immunol, 2001 Jun, 13(3), 187 - 94 Immuno-bacterial homeostasis in the gut: new insights into an old enigma; Elson CO et al.; The intestinal mucosa is the interface between the immune system and the massive antigenic load represented by the commensal enteric bacteria . These commensal bacteria drive the development of the mucosal immune system, and in turn most of the lymphocytes in the intestinal mucosa appear to be specific for enteric bacteria antigens . Proper regulation of the responses of these anti-bacterial lymphocytes are extremely important because T cell effectors reactive to enteric bacterial antigens have been shown to cause chronic intestinal inflammation in an adoptive transfer system . The cells and molecules important in regulating mucosal immune response are now being identified . Insights into the mechanisms of mucosal regulation have come from a number of genetically manipulated mouse strains which develop inflammatory bowel disease in response to the enteric bacterial flora . CD4(+)T cells with regulatory function in the mucosa are being identified; other cell types such as CD8(+)T cells . NK cells, and B cells may also have a role in mucosal immune regulation . A model for T cell-immune homeostasis in the intestinal mucosa is presented . Endocrine, 2001 Mar, 14(2), 205 - 12 High-level bacterial expression of a natively folded, soluble extracellular domain fusion protein of the human luteinizing hormone/chorionic gonadotropin receptor in the cytoplasm of Escherichia coli; Lobel LI et al.; We have expressed the extracellular domain of the human luteinizing hormone/chorionic gonadotropin (hLH/CG) receptor as a fusion protein with thioredoxin in the cytoplasm of an Escherichia coli strain that contains mutations in both the thioredoxin reductase and glutathione reductase genes . The chimeric protein isolated following induction of expression is purified in a soluble form and binds hCG with an affinity approximating that of native receptor . This truncated form of the receptor displays the same specificity as intact hLH/CG receptor and does not bind human follicle stimulating hormone . This cytoplasmically produced protein is expressed at levels that exceed 10 mg/L . Expression of properly folded extracellular domain of the hLH/CG receptor in the cytoplasm of E . coli allows the facile and economic purification of large quantities of material . This will facilitate the determination of the structure of the hormone-binding domain of the glycoprotein receptor as well as the production of epitope-specific antibodies. FEBS Lett, 2001 Jun 1, 498(1), 52 - 6 Complementation of bacterial SecE by a chloroplastic homologue; Froderberg L et al.; The SecE protein is an essential component of the SecAYE-translocase, which mediates protein translocation across the cytoplasmic membrane in bacteria . In the thylakoid membranes of chloroplasts, a protein homologous to SecE, chloroplastic (cp) SecE, has been identified . However, the functional role of cpSecE has not been established experimentally . In this report we show that cpSecE in cells depleted for bacterial SecE (i) supports growth, (ii) stabilizes, just like bacterial SecE, the Sec-translocase core component SecY, and (iii) supports Sec-dependent protein translocation . This indicates that cpSecE can functionally replace bacterial SecE in vivo, and strongly suggests that the thylakoid membrane contains a SecAYE-like translocase with functional and structural similarities to the bacterial complex . This study further underscores the evolutionary link between chloroplasts and bacteria. Biochemistry, 2001 Jun 12, 40(23), 6893 - 902 Identification of the proton pathway in bacterial reaction centers: cooperation between Asp-M17 and Asp-L210 facilitates proton transfer to the secondary quinone (QB); Paddock ML et al.; The reaction center (RC) from Rhodobacter sphaeroides uses light energy to reduce and protonate a quinone molecule, Q(B) (the secondary quinone electron acceptor), to form quinol, Q(B)H2 . Asp-L210 and Asp-M17 have been proposed to be components of the pathway for proton transfer {Axelrod, H . L., Abresch, E . C., Paddock, M . L., Okamura, M . Y., and Feher, G . (2000) Proc . Natl . Acad . Sci . U.S.A . 97, 1542-1547} . To test the importance of these residues for efficient proton transfer, the rates of the proton-coupled electron-transfer reaction k(AB)(2) (Q(A-*)Q(B-*) + H+ <==>Q(A-*)Q(B)H* --> Q(A)Q(B)H-) and its associated proton uptake were measured in native and mutant RCs, lacking one or both Asp residues . In the double mutant RCs, the k(AB)(2) reaction and its associated proton uptake were approximately 300-fold slower than in native RCs (pH 8) . In contrast, single mutant RCs displayed reaction rates that were < or =3-fold slower than native (pH 8) . In addition, the rate-limiting step of k(AB)(2) was changed from electron transfer (native and single mutants) to proton transfer (double mutant) as shown from the lack of a dependence of the observed rate on the driving force for electron transfer in the double mutant RCs compared to the native or single mutants . This implies that the rate of the proton-transfer step was reduced (> or =10(3)-fold) upon replacement of both Asp-L210 and Asp-M17 with Asn . Similar, but less drastic, differences were observed for k(AB)(1), which at pH > or =8 is coupled to the protonation of Glu-L212 {(Q(A-*)Q(B))-Glu- + H+ --> (Q(A)Q(B-*)-GluH} . These results show that the pathway for proton transfer from solution to reduced Q(B) involves both Asp-L210 and Asp-M17, which provide parallel branches to the proton-transfer pathway and through their electrostatic interaction have a cooperative effect on the proton-transfer rate . A possible mechanism for the cooperativity is discussed. Proc Natl Acad Sci U S A, 2001 Jun 5, 98(12), 6560 - 4 Epub 2001 May 29. Large conformational changes of the epsilon subunit in the bacterial F1F0 ATP synthase provide a ratchet action to regulate this rotary motor enzyme; Tsunoda SP et al.; The F(1)F(0) ATP synthase is the smallest motor enzyme known . Previous studies had established that the central stalk, made of the gamma and epsilon subunits in the F(1) part and c subunit ring in the F(0) part, rotates relative to a stator composed of alpha(3)beta(3)deltaab(2) during ATP hydrolysis and synthesis . How this rotation is regulated has been less clear . Here, we show that the epsilon subunit plays a key role by acting as a switch of this motor . Two different arrangements of the epsilon subunit have been visualized recently . The first has been observed in beef heart mitochondrial F(1)-ATPase where the C-terminal portion is arranged as a two-alpha-helix hairpin structure that extends away from the alpha(3)beta(3) region, and toward the position of the c subunit ring in the intact F(1)F(0) . The second arrangement was observed in a structure determination of a complex of the gamma and epsilon subunits of the Escherichia coli F(1)-ATPase . In this, the two C-terminal helices are apart and extend along the gamma to interact with the alpha and beta subunits in the intact complex . We have been able to trap these two arrangements by cross-linking after introducing appropriate Cys residues in E . coli F(1)F(0), confirming that both conformations of the epsilon subunit exist in the enzyme complex . With the C-terminal domain of epsilon toward the F(0), ATP hydrolysis is activated, but the enzyme is fully coupled in both ATP hydrolysis and synthesis . With the C-terminal domain toward the F(1) part, ATP hydrolysis is inhibited and yet the enzyme is fully functional in ATP synthesis; i.e., it works in one direction only . These results help explain the inhibitory action of the epsilon subunit in the F(1)F(0) complex and argue for a ratchet function of this subunit. Genomics, 2001 Jun 1, 74(2), 142 - 54 Five-color-based high-information-content fingerprinting of bacterial artificial chromosome clones using type IIS restriction endonucleases; Ding Y et al.; We have developed a high-information-content fingerprinting (HICF) system for bacterial artificial chromosome (BAC) clones using a Type IIS restriction endonuclease, HgaI, paired with a Type II restriction endonuclease, RsaI . In the method described, unknown five-base overhangs generated with HgaI are partially or fully sequenced by modified fluorescent dideoxy terminators . Using an in-lane size standard labeled with a fifth dye, fragments are characterized by both the size and the sequence of its terminal one to five bases . The enhanced information content associated with this approach significantly increases the accuracy and efficiency of detecting shared fragments among BAC clones . We have compared data obtained from this method to predicted HICF patterns of 10 fully sequenced BACs . We have further applied HICF to 555 BAC clones to assemble contigs spanning 16p11.2 to 16p13.1 of human chromosome 16 . Antonie Van Leeuwenhoek, 2000 Dec, 78(3-4), 315 - 21 Molecular detection of bacterial and streptomycete chitinases in the environment; Williamson N et al.; Sets of PCR primers were designed to amplify bacterial chitinases at different levels of specificity . The bacterial chitinase group primers were successful in targeting enzymes classified within the group A glycosyl hydrolases of family 18 . The widespread occurrence of group A bacterial chitinases in actinomycetes was demonstrated . Streptomycete chitinase specific primers were designed and a collection of type strains of species changed in the genes Streptomyces were screened and shown to have at least one and usually multiple chitinase genes . The presence of the gene for the chitin binding protein was also demonstrated within the streptomycete type strains . These data indicate that streptomycetes are well equipped to degrade chitin . The detection of group A chitinases in total community DNA is described and a sandy soil shown to contain more than 10 different genes using DGGE to indicate genetic diversity. Carbohydr Res, 2001 Apr 12, 331(3), 233 - 7 Synthesis and identification in bacterial lipopolysaccharides of 5,7-diacetamido-3,5,7,9-tetradeoxy-D-glycero-D-galacto- and -D-glycero-D-talo-non-2-ulosonic acids; Tsvetkov YE et al.; 5,7-Diacetamido-3,5,7,9-tetradeoxy-D-glycero-D-galacto- and -D-glycero-D-talo-non-2-ulosonic acids were synthesized by condensation of 2,4-diacetamido-2,4,6-trideoxy-D-mannose with oxalacetic acid . Comparison of the 1H and 13C NMR data and the specific optical rotation values of these monosaccharides and the corresponding L-glycero-D-galacto and L-glycero-D-talo isomers synthesized earlier {Tsvetkov, Y . E.; Shashkov, A . S.; Knirel, Y . A.; Backinowsky, L . V.; Zahringer, U . Mendeleev Commun . 2000, 90-92} with data of the natural compounds enabled the identification in bacterial lipopolysaccharides of derivatives of 5,7-diamino-3,5,7,9-tetradeoxy-D-glycero-D-galacto-non-2-ulosonic (legionaminic) acid and epimers of legionaminic acid at C-4 and C-8. Hepatogastroenterology, 2001 Mar-Apr, 48(38), 502 - 5 Procalcitonin is not an accurate marker of spontaneous bacterial peritonitis in patients with cirrhosis; Spahr L et al.; BACKGROUND/AIMS: The clinical features of peritonitis are usually absent in cirrhotic patients with an ascitic fluid infection, raising the interest for specific biological markers of inflammation . METHODOLOGY: We prospectively measured the plasma and ascitic fluid levels of procalcitonin, an innovative infection parameter, interleukin-6, and C-reactive protein in 20 cirrhotics with or without spontaneous bacterial peritonitis . The patient's condition was followed-up for 12 weeks after paracentesis . RESULTS: None of the 10 patients with spontaneous bacterial peritonitis presented with severe systemic signs of infection . Procalcitonin level in plasma, but not in ascites, was significantly higher in patients with spontaneous bacterial peritonitis compared to controls (0.74 +/- 0.6 vs . 0.2 +/- 0.1 ng/mL, P < 0.05) . Interleukin-6 levels in ascites were similar between groups . C-reactive protein concentrations were higher both in plasma and in ascitic fluid in patients with spontaneous bacterial peritonitis compared to controls (85.3 +/- 63 vs . 18.6 +/- 19 mg/dL, 24.6 +/- 25 vs . 4.5 +/- 4 mg/dL, P < 0.05, respectively) . Three patients with spontaneous bacterial peritonitis died, but the outcome was not related to the concentrations of biological markers . CONCLUSIONS: In spontaneous bacterial peritonitis, procalcitonin measurement is not an accurate diagnostic test, possibly due to the absence of systemic inflammatory response syndrome in this condition . In addition, the diagnostic value of C-reactive protein is limited by the wide overlap between values. Curr Opin Microbiol, 2001 Jun, 4(3), 267 - 73 Bacterial antigens elicit T cell responses via adaptive and transitional immune recognition; Cookson BT et al.; T cells are a critical component of host immune responses against bacterial pathogens . T cell activation relies on recognition of antigen(s) derived from the bacteria, and this activation triggers potent biological effector mechanisms . Therefore, the characterization of antigens that are stimulatory for T cells provides insight into host-pathogen interactions and advances rational vaccine design . The adaptive immune response is defined by its ability to detect variable or unique single-gene products, whereas a 'transitional' immune system recognizes more conserved structures or products of multigene pathways . This transitional system functionally overlaps the canonical innate and adaptive immune responses . Antigen identification has relied upon biochemistry, genetics and expression cloning strategies . The development of computational approaches, fuelled by advances in immunology and genomic information, will facilitate the discovery of antigens and expand our understanding of both beneficial and pathological immune responses. Curr Biol, 2001 May 15, 11(10), R395 - 8 Bacterial cell division: a moving MinE sweeper boggles the MinD; Margolin W; Placement of the division site in Escherichia coli is determined in part by three Min proteins . Recent studies have shown that MinE, previously thought to form a static ring near the division site at the midcell position, actually joins MinC and MinD in their rapid oscillation between the cell poles. Bioorg Med Chem Lett, 2001 Jun 4, 11(11), 1451 - 4 Inhibitors of the bacterial cell wall biosynthesis enzyme MurC; Reck F et al.; A series of phosphinate transition-state analogues of the L-alanine adding enzyme (MurC) of bacterial peptidoglycan biosynthesis was prepared and tested as inhibitors of the Escherichia coli enzyme . Compound 4 was identified as a potent inhibitor of MurC from Escherichia coli with an IC(50) of 49nM. FEMS Microbiol Ecol, 2001 Jun, 36(1), 73 - 84 Microcosm-based analyses of Scots pine seedling growth, ectomycorrhizal fungal community structure and bacterial carbon utilization profiles in boreal forest humus and underlying illuvial mineral horizons; Heinonsalo J et al.; We report on the identity of indigenous mycorrhiza forming fungi and rhizosphere/mycorrhizosphere bacterial community carbon source utilization profiles of Scots pine (Pinus sylvestris L.) seedlings grown in boreal forest humus (O) or illuvial (B) mineral horizon containing microcosm growth systems . Based on rDNA (ITS)-RFLP analyses, a total of 10 fungal RFLP taxa were identified from pre-morphotyped mycorrhizas on 7-month-old seedling roots . Hierarchical cluster analysis, including corresponding RFLPs of known fungal species, confirmed root colonization by eight mycorrhizal species . In the O horizon, roots were colonized by e.g . Suillus bovinus, Suillus variegatus, Cenococcum geophilum, Piloderma croceum, Thelephora terrestris and Russula vinicolor . Mycobiont diversity in the mineral B horizon was lower but included Piceirhiza bicolorata and both Suillus species which produced extensive extramatrical mycelium . In comparison to non-colonized soils, rhizosphere and mycorrhizosphere compartments supported significantly higher numbers of bacteria (mean range 10(8)-10(11) cells g(-1) fresh weight (fw)) . Specific rhizosphere/mycorrhizosphere 'niche'-linked bacterial communities were detected following multivariate analyses (PCA and CA) of bacterial carbon utilization profiles (Biolog(R) GN microplate) . Distinct preferences for amino and carboxylic acids were identified in mineral B horizon rhizospheres whereas a wider range of carbon sources were utilized in the fungal-dominated mycorrhizospheres irrespective of soil types. FEMS Microbiol Ecol, 2001 Jun, 36(1), 1 - 9 Effects of mercury contamination on the culturable heterotrophic, functional and genetic diversity of the bacterial community in soil; Rasmussen LD et al.; This study investigates the effect of mercury contamination on the culturable heterotrophic, functional and genetic diversity of the bacterial community in soil . The changes in diversity were monitored in soil microcosms, enriched with 25 &mgr;g Hg(II) g(-1) soil, over a period of 3 months . The culturable heterotrophic diversity was investigated by colony morphology and colony appearance on solid LB medium . Functional diversity was analysed as sole carbon utilisation patterns in ECOplates . Genetic diversity was measured as bands on denaturing gradient gel electrophoresis (DGGE) gels obtained by purification of total soil DNA and amplification of bacterial 16S rDNA fragments by polymerase chain reaction . Concentrations of bioavailable and total mercury were measured throughout the experiment . The effect on the culturable heterotrophic and genetic diversity was very similar, showing an immediate decrease after mercury addition but then slowly increasing throughout the entire experimental period . Pre-exposure levels were not reached within the time span of this investigation . The DGGE band pattern indicated that a shift in the community structure was responsible for recovered diversity . When analysed by Shannon-Weaver indices, functional diversity was found to increase almost immediately after mercury addition and to remain at a level higher than the control soil for the rest of the experiment . The fraction of culturable heterotrophic bacteria increased from 1% to 10% of the total bacterial number as a result of mercury addition, and the mercury-resistant population increased to represent the entire heterotrophic population. Gastroenterology, 2001 Jun, 120(7), 1666 - 79 Colonic epithelial hPepT1 expression occurs in inflammatory bowel disease: transport of bacterial peptides influences expression of MHC class 1 molecules; Merlin D et al.; BACKGROUND & AIMS: hPepT1 is an intestinal epithelial apical membrane transporter responsible for uptake of di/tripeptides (including bacterial derived proinflammatory n-formyl peptides) . hPepT1 expression normally has a strict axial gradient-highest in the proximal small intestine with no expression in the colon . METHODS: Small intestinal-like cells (Caco2-BBE), and colonic-like cells (HT29-Cl.19A), and colonic mucosa from diseased and control patients were used in the present study . RESULTS: hPepT1 expression occurs aberrantly in the colon with chronic ulcerative colitis (6 patients) and Crohn's disease (4 patients), but not in normal colon (4 patients) or colon with microscopic colitis (4 patients) . To model expression of hPepT1 by colonic-like cells in inflamed states, we stably transfected HT29-Cl.19A cells with a modified hPepT1 tagged on the N-terminus with green fluorescence protein . Analysis of transfected cells revealed that: GFP-hPepT1 protein, like the natural protein, is targeted to the apical plasma membrane . In addition, the tagged protein retains the capability of di/tripeptide absorption, and the expression of the tagged protein by HT29-Cl.19A cells permits absorption of N-formyl-methionyl-leucyl-phenylalanine (fMLP), as occurs in hPepT1 expressing Caco2-BBE cells . fMLP uptake by colonic cells expressing GFP-hPepT1 specifically enhances major histocompatibility complex class I surface expression . CONCLUSIONS: These data collectively indicate that, in some states of chronic inflammation, hPepT1 may be anomolously expressed in the colon . Further, transport of fMLP by hPepT1 potentially stimulates expression of key accessory immune molecule, MHC-1. Acta Crystallogr D Biol Crystallogr, 2001 Jun, 57(Pt 6), 884 - 5 Epub 2001 May 25. Crystallization and preliminary X-ray analysis of AlgS, a bacterial ATP-binding cassette (ABC) protein specific to macromolecule import; Mishima Y et al.; Sphingomonas sp . A1 possesses a macromolecule (alginate; average molecular size 25 700 Da) uptake system mediated by a novel pit-dependent ABC transporter . In this system, AlgS (363 amino-acid residues; 40 kDa) functions as an ATPase and provides energy for the translocation of high molecular-weight alginate across the cytoplasmic membrane . Hexahistidine-tagged AlgS of Sphingomonas sp . A1 was overexpressed in Escherichia coli and crystallized by means of the hanging-drop vapour-diffusion method with ammonium dihydrogen monophosphate as the precipitant . Preliminary X-ray analysis of the resultant crystals was performed; they belonged to the monoclinic space group P2(1) and had unit-cell parameters a = 57.4, b = 92.7, c = 65.8 A, beta = 102.3 degrees . X-ray diffraction data to 3.2 A have been collected from the native crystal. Appl Environ Microbiol, 2001 Jun, 67(6), 2849 - 52 Quantitative PCR method for diagnosis of citrus bacterial canker; Cubero J et al.; For diagnosis of citrus bacterial canker by PCR, an internal standard is employed to ensure the quality of the DNA extraction and that proper requisites exist for the amplification reaction . The ratio of PCR products from the internal standard and bacterial target is used to estimate the initial bacterial concentration in citrus tissues with lesions. Appl Environ Microbiol, 2001 Jun, 67(6), 2469 - 75 Selection of specific endophytic bacterial genotypes by plants in response to soil contamination; Siciliano SD et al.; Plant-bacterial combinations can increase contaminant degradation in the rhizosphere, but the role played by indigenous root-associated bacteria during plant growth in contaminated soils is unclear . The purpose of this study was to determine if plants had the ability to selectively enhance the prevalence of endophytes containing pollutant catabolic genes in unrelated environments contaminated with different pollutants . At petroleum hydrocarbon contaminated sites, two genes encoding hydrocarbon degradation, alkane monooxygenase (alkB) and naphthalene dioxygenase (ndoB), were two and four times more prevalent in bacteria extracted from the root interior (endophytic) than from the bulk soil and sediment, respectively . In field sites contaminated with nitroaromatics, two genes encoding nitrotoluene degradation, 2-nitrotoluene reductase (ntdAa) and nitrotoluene monooxygenase (ntnM), were 7 to 14 times more prevalent in endophytic bacteria . The addition of petroleum to sediment doubled the prevalence of ndoB-positive endophytes in Scirpus pungens, indicating that the numbers of endophytes containing catabolic genotypes were dependent on the presence and concentration of contaminants . Similarly, the numbers of alkB- or ndoB-positive endophytes in Festuca arundinacea were correlated with the concentration of creosote in the soil but not with the numbers of alkB- or ndoB-positive bacteria in the bulk soil . Our results indicate that the enrichment of catabolic genotypes in the root interior is both plant and contaminant dependent. J Infect Dis, 2001 Jun 15, 183(12), 1749 - 59 Epub 2001 May 15. Differential expression of nitric oxide synthases in bacterial meningitis: role of the inducible isoform for blood-brain barrier breakdown; Winkler F et al.; The aim of the study was to determine the differential expression of nitric oxide (NO) synthase (NOS) isoforms and the pathophysiologic relevance of inducible NOS (iNOS) in experimental pneumococcal meningitis . By use of reverse transcription-polymerase chain reaction analysis, immunohistochemistry, and Western blotting, increased brain mRNA and increased protein levels of endothelial NOS (eNOS) and iNOS were detected 24 h after intracisternal pneumococcal inoculation . In iNOS-deficient mice, disruption of the blood-brain barrier (BBB) was significantly reduced, compared with that in wild-type mice . This beneficial effect of iNOS deficiency was associated with a lack of nitrotyrosine immunoreactivity . Furthermore, brain protein levels of interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha and brain mRNA levels of macrophage inflammatory protein (MIP)-1alpha and MIP-2 were significantly reduced in infected animals lacking iNOS . These findings suggest that (1) not only iNOS but also eNOS is up-regulated in the acute phase of experimental bacterial meningitis, and (2) iNOS-derived NO contributes to peroxynitrite formation and BBB breaching in this disease. Infect Dis Obstet Gynecol, 2001, 9(1), 9 - 15 Efficacy of clindamycin vaginal ovule (3-day treatment) vs . clindamycin vaginal cream (7-day treatment) in bacterial vaginosis; Sobel J et al.; OBJECTIVE: To compare the efficacy and safety of a 3-day regimen of clindamycin vaginal ovules with a 7-day regimen of clindamycin vaginal cream for the treatment of bacterial vaginosis (BV) . METHODS: Women with a clinical diagnosis of BV were treated with a 3-day course of clindamycin ovules or a 7-day course of clindamycin cream administered intravaginally . Three hundred and eighty-four patients received study drug and were included in the evaluable patient population (ovule group, n = 204; cream group, n = 180) . Assessments included pelvic examination and diagnostic testing . Primary efficacy endpoints were a resolution of two of three diagnostic criteria at the first follow-up visit and three of three diagnostic criteria at the second . RESULTS: Cure rates in the evaluable patient population were similar between treatment groups: 53.7% (109/204) for the ovule group and 47.8% (85/180) for the cream group (p = 0.2471, 95% CI -4.1-16.0%) . The most commonly reported medical event, vulvovaginal pruritus, had similar incidence in both treatment groups . CONCLUSIONS: A 3-day course of clindamycin vaginal ovules is as effective and well-tolerated as a 7-day course of clindamycin vaginal cream in the treatment of BV. Zhongguo Yi Xue Ke Xue Yuan Xue Bao, 1998 Jun, 20(3), 161 - 6 {Construction of a pufferfish bacterial artificial chromosome library}; Liu S et al.; OBJECTIVE: Study of human genome by taking advantage of investigating pufferfish's (Fugu rubripes), compact model vertebrate genome . METHODS: Construct a pufferfish bacterial artificial chromosome (BAC) library using Japanese pufferfish (Fugu rubripes) sperm DNA and pBelo BAC11 vector . RESULTS: The library consists of 23,040 clones, which have been arrayed in 240,96-well microtiter plates . 100 BAC clones have been selected at random and analyzed for estimation of the average insert size, which turns out to be 100 kb indicating its nearly 6-fold coverage of pufferfish haploid genome . Restrict analysis of 10 BAC clones show that these inserts are stable even propagated for at least 100 cell generations . CONCLUSIONS: The library accords with the demands of a BAC library. Zhongguo Zhong Xi Yi Jie He Za Zhi, 1998 Feb, 18(2), 104 - 6 {Experimental study on mechanism of xiukeyin in anti-bacterial translocation from gut}; Zhang P et al.; OBJECTIVE: To provide a TCM therapeutic base for treatment of critical multiple organ failure (MOF) patients clinically, the mechanism of Xiukeyin (XKY, Shock Beverage) in anti-bacterial translocation from gut in rats was studied . METHODS: Based on the pathophysiology of MOF following severe injury, such as shock caused enterogenous-sepsis and bacterial translocation from gut, a hemorrhagic shock model of rat was established and used to determine the effect of XKY on anti-bacterial translocation . XKY was formulated by modifying Wenpi Decoction . RESULTS: The incidence of intestinal bacterial translocation to mesenteric lymph nodes, liver and spleen was lower in the model rats infused via gastrogavage with XKY (3/15) than that in the noninfused rats (11/13) (P < 0.01) . The amount and species of intestinal flora in XKY infused or noninfused rats were not different statistically (P > 0.05) . Histological examination showed that the intestinal edema was severer in the model group than that in the XKY treated group . CONCLUSIONS: XKY could inhibit the shock induced enterogenous bacterial translocation, the mechanism might be due to its protective action on intestinal mucosa . XKY showed no effect on the growth of intestinal bacteria. Posit Health News, 1998 Fall, (No 17), 26 - 7 Essential oils of peppermint, orange or lemongrass kill most strains of fungal and bacterial infections; Bacterial infections; University of Texas, Southwestern Medical Center, Dallas, TXAIDS: Bacterial skin infections normally pose no threat to an immunocompetent patient but may threaten a seropositive one . For this reason, skin biopsies and cultures should be performed in any immunocompromised patients where bacterial infections are present . The epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment options for some of the many bacterial skin infections that occur in HIV infection are discussed . Mol Microbiol, 2001 May, 40(3), 731 - 43 Acetylation of the response regulator, CheY, is involved in bacterial chemotaxis; Barak R et al.; It is well established that the response regulator of the chemotaxis system of Escherichia coli, CheY, can undergo acetylation at lysine residues 92 and 109 via a reaction mediated by acetyl-CoA synthetase (Acs) . The outcome is activation of CheY, which results in increased clockwise rotation . Nevertheless, it has not been known whether CheY acetylation is involved in chemotaxis . To address this question, we examined the chemotactic behaviour of two mutants, one lacking the acetylating enzyme Acs, and the other having an arginine-for-lysine substitution at residue 92 of CheY - one of the acetylation sites . The Deltaacs mutant exhibited much reduced sensitivity to chemotactic stimuli (both attractants and repellents) in tethering assays and greatly reduced responses in ring-forming, plug and capillary assays . Likewise, the cheY(92KR) mutant had reduced sensitivity to repellents in tethering assays and a reduced response in capillary assays . However, its response to the addition or removal of attractants was normal . These observations suggest that Acs-mediated acetylation of CheY is involved in chemotaxis and that the acetylation site Lys-92 is only involved in the response to repellents . The observation that, in the cheY(92KR) mutant, the addition of a repellent was not chemotactically equivalent to the removal of an attractant also suggests that there are different signalling pathways for attractants and repellents in E . coli. J Biol Chem, 2001 Jul 20, 276(29), 27597 - 604 Epub 2001 May 17. Molecular characterization of the 4'-phosphopantothenoylcysteine decarboxylase domain of bacterial Dfp flavoproteins; Kupke T; The NH(2)-terminal domain of the bacterial flavoprotein Dfp catalyzes the decarboxylation of (R)-4'-phospho-N-pantothenoylcysteine to 4'-phosphopantetheine, a key step in coenzyme A biosynthesis . Dfp proteins, LanD proteins (for example EpiD, which is involved in epidermin biosynthesis), and the salt tolerance protein AtHAL3a from Arabidopsis thaliana are homooligomeric flavin-containing Cys decarboxylases (HFCD protein family) . The crystal structure of the peptidyl-cysteine decarboxylase EpiD complexed with a pentapeptide substrate has recently been determined . The peptide is bound by an NH(2)-terminal substrate binding helix, residue Asn(117), which contacts the cysteine residue of the substrate, and a COOH-terminal substrate recognition clamp . The conserved motif G-G/S-I-A-X-Y-K of the Dfp proteins aligns partly with the substrate binding helix of EpiD . Point mutations within this motif resulted in loss of coenzyme binding (G14S) or in significant decrease of Dfp activity (G15A, I16L, A17D, K20N, K20Q) . Exchange of Asn(125) of Dfp, which corresponds to Asn(117) of EpiD, and exchange of Cys(158), which is within the proposed substrate recognition clamp of Dfp, led to inactivity of the enzyme . Molecular analysis of the conditional lethality of the Escherichia coli dfp-707 mutant revealed that the single point mutation G11D of Dfp is related to decreased amounts of soluble Dfp protein at 37 degrees C. J Virol, 2001 Jun, 75(12), 5692 - 6 Virus reconstituted from infectious bacterial artificial chromosome (BAC)-cloned murine gammaherpesvirus 68 acquires wild-type properties in vivo only after excision of BAC vector sequences; Adler H et al.; We studied the in vivo biological properties of viruses reconstituted from the genome of murine gammaherpesvirus 68 (MHV-68) cloned as an infectious bacterial artificial chromosome (BAC) . Recombinant virus RgammaHV68A98.01, containing BAC vector sequences, is attenuated in vivo as determined by (i) viral titers in the lungs during the acute phase of infection, (ii) the extent of splenomegaly, and (iii) the number of latently infected spleen cells reactivating virus in an ex vivo reactivation assay . Since the BAC vector sequences were flanked by loxP sites, passaging the virus in fibroblasts expressing Cre recombinase resulted in the generation of recombinant virus RgammaHV68A98.02, with biological properties comparable to those of wild-type MHV-68 . On the basis of these data we conclude (i) that excision of BAC vector sequences from cloned MHV-68 genomes is critical for reconstitution of the wild-type phenotypic properties of this virus and (ii) that the BAC-cloned MHV-68 genome is suitable for the construction of mutants and mutant libraries whose phenotypes can be reliably assessed in vivo. Anal Chem, 2001 May 1, 73(9), 2132 - 9 Quantitative analysis of bacterial and mammalian proteomes using a combination of cysteine affinity tags and 15N-metabolic labeling; Conrads TP et al.; We describe the combined use of 15N-metabolic labeling and a cysteine-reactive biotin affinity tag to isolate and quantitate cysteine-containing polypeptides (Cys-polypeptides) from Deinococcus radiodurans as well as from mouse B16 melanoma cells . D . radiodurans were cultured in both natural isotopic abundance and 15N-enriched media . Equal numbers of cells from both cultures were combined and the soluble proteins extracted . This mixture of isotopically distinct proteins was derivatized using a commercially available cysteine-reactive reagent that contains a biotin group . Following trypsin digestion, the resulting modified peptides were isolated using immobilized avidin . The mixture was analyzed by capillary reversed-phase liquid chromatography (LC) online with ion trap mass spectrometry (MS) as well as Fourier transform ion cyclotron resonance (FTICR) MS . The resulting spectra contain numerous pairs of Cyspolypeptides whose mass difference corresponds to the number of nitrogen atoms present in each of the peptides . Designation of Cys-polypeptide pairs is also facilitated by the distinctive isotopic distribution of the 15N-labeled peptides versus their 14N-labeled counterparts . Studies with mouse B16 cells maintained in culture allowed the observation of hundreds of isotopically distinct pairs of peptides by LC-FTICR analysis . The ratios of the areas of the pairs of isotopically distinct peptides showed the expected 1:1 labeling of the 14N and 15N versions of each peptide . An additional benefit from the present strategy is that the 15N-labeled peptides do not display significant isotope-dependent chromatographic shifts from their 14N-labeled counterparts, therefore improving the precision for quantitating peptide abundances . The methodology presented offers an alternate, cost-effective strategy for conducting global, quantitative proteomic measurements. Foot Ankle Int, 2001 Apr, 22(4), 347 - 50 Bacterial recolonization during foot surgery: a prospective randomized study of toe preparation techniques; Brooks RA et al.; Fifty patients undergoing foot or ankle surgery were randomized into two groups for the purposes of toe preparation . Twenty-four patients underwent a standard preparation which included placing antiseptic between the toes while 26 were additionally cleaned by sliding a gauze swab soaked in topical antiseptic back and forth several times . Povidone iodine followed by chlorhexidine in alcohol was used in both groups . All toes were covered by a sterile glove during surgery unless the toes themselves were to be operated upon . Bacteria were cultured from the toe clefts in 4% of all patients immediately following preoperative disinfection . Significantly fewer patients whose toes had been additionally scrubbed (group 1) showed bacterial recolonization at the end of surgery compared with those undergoing a standard prep (group 2) (7.7% vs 20.8%) . We conclude that additional scrubbing of toe clefts prior to surgery reduces the incidence of recolonization of bacteria during the surgical procedure. Eur J Surg, 2001 Apr, 167(4), 299 - 304 Tumour necrosis factor mediates bacterial translocation after haemorrhagic shock and endotoxaemia; Goldman G et al.; OBJECTIVE: To assess the extent of bacterial translocation after haemorrhagic shock and reperfusion, and the involvement of tumour necrosis factor (TNF) in its mediation . DESIGN: Controlled, randomised prospective experiment . SUBJECTS: 87 rats in 7 groups . INTERVENTIONS: Haemorrhagic shock was induced in rats for 1 hour . Endotoxaemia was induced in a second group by the injection of lipopolysaccharide . A third group was injected with exogenous TNF . Some of the animals were further treated with anti-TNF . MEASUREMENTS: After 24 hours, bacterial translocation in blood and in several remote organs, and serum TNF concentrations were measured . RESULTS: High bacterial counts were found in all remote organs of rats with haemorrhagic shock or endotoxaemia . Their serum TNF concentrations were significantly higher than in the corresponding sham-operated controls . Anti-TNF significantly reduced the extent of bacterial translocation . Rats, the only treatment of which was exogenous TNF, developed substantial bacterial translocation . CONCLUSION: Bacterial translocation is associated with increased serum TNF, and can be minimised by anti-TNF . This, and the triggering of translocation in unprovoked animals by TNF alone, suggest that TNF may be the stimulator, and not the consequence, of bacterial translocation. Sex Transm Dis, 2001 May, 28(5), 292 - 7 Preventing adverse sequelae of bacterial vaginosis: a public health program and research agenda; Koumans EH et al.; BACKGROUND: The cause of bacterial vaginosis remains poorly understood . Recent evidence strengthens the association between bacterial vaginosis and serious medical complications . GOAL: To review the evidence linking bacterial vaginosis with adverse pregnancy outcomes, complications after gynecologic procedures, and HIV infection, and to identify prevention strategies . METHODS: In March 1999, the Centers for Disease Control and Prevention organized a conference to accomplish this goal . RESULTS: Better understanding is needed concerning the etiology, epidemiology, and natural history of bacterial vaginosis . More efficacious treatment of bacterial vaginosis and strategies to reduce maternal complications associated with bacterial vaginosis, such as premature rupture of the fetal membranes, chorioamnionitis, premature labor and delivery, postdelivery endometritis, and postpartum infant complications should be developed . Recent evidence shows that screening and treatment of bacterial vaginosis before abortion reduces postabortion pelvic inflammatory disease, and that anaerobic coverage during hysterectomy reduces postoperative complications . Better understanding concerning the relation of bacterial vaginosis to acquisition of sexually transmitted diseases and HIV infection are needed as well as possible prevention strategies . CONCLUSIONS: A national prevention effort should be guided by the results of research that addresses current knowledge gaps. Biochemistry, 2001 May 22, 40(20), 6132 - 41 Cu2+ site in photosynthetic bacterial reaction centers from Rhodobacter sphaeroides, Rhodobacter capsulatus, and Rhodopseudomonas viridis; Utschig LM et al.; The interaction of metal ions with isolated photosynthetic reaction centers (RCs) from the purple bacteria Rhodobacter sphaeroides, Rhodobacter capsulatus, and Rhodopseudomonas viridis has been investigated with transient optical and magnetic resonance techniques . In RCs from all species, the electrochromic response of the bacteriopheophytin cofactors associated with Q(A)(-)Q(B) --> Q(A)Q(B)(-) electron transfer is slowed in the presence of Cu(2+) . This slowing is similar to the metal ion effect observed for RCs from Rb . sphaeroides where Zn(2+) was bound to a specific site on the surface of the RC {Utschig et al . (1998) Biochemistry 37, 8278} . The coordination environments of the Cu(2+) sites were probed with electron paramagnetic resonance (EPR) spectroscopy, providing the first direct spectroscopic evidence for the existence of a second metal site in RCs from Rb . capsulatus and Rps . viridis . In the dark, RCs with Cu(2+) bound to the surface exhibit axially symmetric EPR spectra . Electron spin echo envelope modulation (ESEEM) spectral results indicate multiple weakly hyperfine coupled (14)N nuclei in close proximity to Cu(2+) . These ESEEM spectra resemble those observed for Cu(2+) RCs from Rb . sphaeroides {Utschig et al . (2000) Biochemistry 39, 2961} and indicate that two or more histidines ligate the Cu(2+) at the surface site in each RC . Thus, RCs from Rb . sphaeroides, Rb . capsulatus, and Rps . viridis each have a structurally analogous Cu(2+) binding site that is involved in modulating the Q(A)(-)Q(B) --> Q(A)Q(B)(-) electron-transfer process . Inspection of the Rps . viridis crystal structure reveals four potential histidine ligands from three different subunits (M16, H178, H72, and L211) located beneath the Q(B) binding pocket . The location of these histidines is surprisingly similar to the grouping of four histidine residues (H68, H126, H128, and L211) observed in the Rb . sphaeroides RC crystal structure . Further elucidation of these Cu(2+) sites will provide a means to investigate localized proton entry into the RCs of Rb . capsulatus and Rps . viridis as well as locate a site of protein motions coupled with electron transfer. Science, 2001 May 11, 292(5519), 1115 - 8 Commensal host-bacterial relationships in the gut; Hooper LV et al.; One potential outcome of the adaptive coevolution of humans and bacteria is the development of commensal relationships, where neither partner is harmed, or symbiotic relationships, where unique metabolic traits or other benefits are provided . Our gastrointestinal tract is colonized by a vast community of symbionts and commensals that have important effects on immune function, nutrient processing, and a broad range of other host activities . The current genomic revolution offers an unprecedented opportunity to identify the molecular foundations of these relationships so that we can understand how they contribute to our normal physiology and how they can be exploited to develop new therapeutic strategies. Science, 2001 May 11, 292(5519), 1096 - 9 Genes lost and genes found: evolution of bacterial pathogenesis and symbiosis; Ochman H et al.; Traditionally, evolutionary biologists have viewed mutations within individual genes as the major source of phenotypic variation leading to adaptation through natural selection, and ultimately generating diversity among species . Although such processes must contribute to the initial development of gene functions and their subsequent fine-tuning, changes in genome repertoire, occurring through gene acquisition and deletion, are the major events underlying the emergence and evolution of bacterial pathogens and symbionts . Furthermore, pathogens and symbionts depend on similar mechanisms for interacting with hosts and show parallel trends in genome evolution. EMBO J, 2001 May 15, 20(10), 2472 - 9 Functional reconstitution of bacterial Tat translocation in vitro; Yahr TL et al.; The Tat (twin-arginine translocation) pathway is a Sec-independent mechanism for translocating folded preproteins across or into the inner membrane of Escherichia coli . To study Tat translocation, we sought an in vitro translocation assay using purified inner membrane vesicles and in vitro synthesized substrate protein . While membrane vesicles derived from wild-type cells translocate the Sec-dependent substrate proOmpA, translocation of a Tat-dependent substrate, SufI, was not detected . We established that in vivo overexpression of SufI can saturate the Tat translocase, and that simultaneous overexpression of TatA, B and C relieves this SufI saturation . Using membrane vesicles derived from cells overexpressing TatABC, in vitro translocation of SufI was detected . Like translocation in vivo, translocation of SufI in vitro requires TatABC, an intact membrane potential and the twin-arginine targeting motif within the signal peptide of SUFI: In contrast to Sec translocase, we find that Tat translocase does not require ATP . The development of an in vitro translocation assay is a prerequisite for further biochemical investigations of the mechanism of translocation, substrate recognition and translocase structure. EMBO J, 2001 May 15, 20(10), 2462 - 71 Projection structure and oligomeric properties of a bacterial core protein translocase; Collinson I et al.; The major route for protein export or membrane integration in bacteria occurs via the Sec-dependent transport apparatus . The core complex in the inner membrane, consisting of SecYEG, forms a protein-conducting channel, while the ATPase SecA drives translocation of substrate across the membrane . The SecYEG complex from Escherichia coli was overexpressed, purified and crystallized in two dimensions . A 9 A projection structure was calculated using electron cryo-microscopy . The structure exhibits P12(1) symmetry, having two asymmetric units inverted with respect to one another in the unit cell . The map shows elements of secondary structure that appear to be transmembrane helices . The crystallized form of SecYEG is too small to comprise the translocation channel and does not contain a large pore seen in other studies . In detergent solution, the SecYEG complex displays an equilibrium between monomeric and tetrameric forms . Our results therefore indicate that, unlike other known channels, the SecYEG complex can exist as both an assembled channel and an unassembled smaller unit, suggesting that transitions between the two states occur during a functional cycle. EMBO J, 2001 May 15, 20(10), 2454 - 61 Crystal structure of the bacterial cell division inhibitor MinC; Cordell SC et al.; Bacterial cell division requires accurate selection of the middle of the cell, where the bacterial tubulin homologue FtsZ polymerizes into a ring structure . In Escherichia coli, site selection is dependent on MinC, MinD and MINE: MinC acts, with MinD, to inhibit division at sites other than the midcell by directly interacting with FTSZ: Here we report the crystal structure to 2.2 A of MinC from Thermotoga maritima . MinC consists of two domains separated by a short linker . The C-terminal domain is a right-handed beta-helix and is involved in dimer formation . The crystals contain two different MinC dimers, demonstrating flexibility in the linker region . The two-domain architecture and dimerization of MinC can be rationalized with a model of cell division inhibition . MinC does not act like SulA, which affects the GTPase activity of FtsZ, and the model can explain how MinC would select for the FtsZ polymer rather than the monomer. J Clin Periodontol, 2001 May, 28(5), 476 - 82 Immunization to Porphyromonas gingivalis enhances the local pro-inflammatory response to subcutaneous bacterial challenge; Houri-Haddad Y et al.; BACKGROUND, AIMS: Human and animal studies have suggested that immunization to P . gingivalis might be beneficial for controlling periodontitis, by the induction of protective antibody response . The present study was designed to examine the effect of immunization on the local cellular, cytokine and antibody response to P . gingivalis in mice . METHODS: Subcutaneous chambers were implanted in 3 groups of mice . 2 groups were then immunized with P . gingivalis in either incomplete Freund's (IFA) or an Alum-based adjuvant . The 3rd group served as the control . At baseline, all mice were challenged with an intra-chamber injection of P . gingivalis . Chamber exudates were sampled at baseline, 1 and 7 days post-challenge, following by determination of leukocyte counts and the cytokines TNF-alpha, IFNgamma (pro-inflammatory) and IL-10 (anti-inflammatory) . IgG levels to P . gingivalis were analyzed in both the exudates and serum . RESULTS: Leukocyte accumulation increased in the chambers over the study period and was more marked in the immunized groups . P . gingivalis challenge induced the expression of the tested cytokines in all groups . Levels of IFNgamma showed a significantly greater increase in the immunized groups on day 1 post-challenge . By day 7, the levels in the controls had reached those of the immunized groups . IL-10 levels were significantly higher in the control group compared to the immunized groups on day 1 and by day 7 they were reduced significantly in all groups to barely detectable levels . While there were no significant differences in TNF-alpha levels between IFA and control groups, they were significantly higher in the Alum group on day 0 and 7 . Both immunization protocols induced anti-P . gingivalis IgG . The Alum group achieved the highest antibody levels, which were due to the increased expression of IgG1, a marker of a Th2-response . CONCLUSIONS: The results suggest that immunization to P . gingivalis results in enhanced expression of pro-inflammatory, tissue-destructive cytokines in the inflammatory site . The nature of the adjuvant used for immunization allows manipulation of the T-cell response, and alum was more effective in reducing the inflammatory response than IFA. J Microbiol Methods, 2001 Jul, 45(3), 155 - 65 Extraction and purification of DNA in rhizosphere soil samples for PCR-DGGE analysis of bacterial consortia; Maarit Niemi R et al.; Application of DNA fingerprinting methods enables the detection of diverse members of soil bacterial consortia, even including those bacteria not yet cultivated . However, extraction and purification of DNA from soil samples without bias is difficult . We compared five different DNA isolation methods and three purification methods for rhizosphere soil samples . Purified DNA extracts were amplified in PCR using universal bacterial primers and the PCR products were analysed with denaturing gradient gel electrophoresis (DGGE) for the visualisation of DNA bands representing dominant bacterial species . Both the isolation and purification methods affected the apparent bacterial community structure of the samples. Am J Clin Pathol, 2001 May, 115(5), 644 - 9 Manual differential cell counts help predict bacterial infection . A multivariate analysis; Wile MJ et al.; We developed logistic regression models that combine information from the automated CBC and manual 100-cell differential counts to predict bacterial infection . The logistic models were fitted from a case group of 116 patients with proven bacterial infection and a control group of 930 presumably uninfected outpatients . A 4-variable, 15-parameter model, which includes automated absolute neutrophil, manual band, and manual immature granulocyte counts, performed best with a receiver operating characteristic (ROC) curve area of 89% . A more practical 2-variable model including automated absolute neutrophil and manual band counts performed almost as well with an ROC curve area of 86% . The automated neutrophil count-only model is less informative with an ROC curve area of 78% . The combined information from automated and manual differential cell counts more accurately predicts bacterial infection than automated counting alone . Despite these modest improvements, the high cost of manual differential cell counts dictates careful patient selection . The supplemental information gained from manual differential counts is most useful for patients with low to normal neutrophil counts (8,000/microL {8.0 x 10(9)/L} or less) . Further studies are indicated to determine the characteristic patient populations deriving maximal benefit from this information. Neurosci Lett, 2001 May 25, 304(3), 177 - 80 Synergistic apoptosis induced by bacterial endotoxin lipopolysaccharide and high glucose in rat microglia; Wang JY et al.; The present study investigates whether bacterial lipopolysaccharide (LPS) in the presence of increased levels of glucose induced synergistic cytotoxicity in primary cultured microglia . Significant cytotoxicity was only observed while the concentrations of LPS were increased to 10 microg/ml . D-glucose concentration-dependently (25-125 mM) generated cytotoxicity . Synergistic apoptosis of microglia was seen by LPS in the presence of increased levels of D-glucose . This synergistic cytotoxicity was attenuated by the use of superoxide dimutase and catalase, suggesting the involvement of oxidative free radicals . Collectively, the present results suggest that increased ambient levels of glucose rendered microglia vulnerable to LPS insults, and led to a synergistic apoptosis . The findings here may be important in certain patho-physiological implications in which hyperglycemia exacerbated the ambient functions contributed by microglia, and may provide new insight into a novel therapeutic intervention. Mutat Res, 2001 Feb 20, 490(2), 89 - 98 Halogenated 2,5-pyrrolidinediones: synthesis, bacterial mutagenicity in Ames tester strain TA-100 and semi-empirical molecular orbital calculations; Freeman BA et al.; The chloroimide 3,3-dichloro-4-(dichloromethylene)-2,5-pyrrolidinedione, a tetrachloroitaconimide, is the principal mutagen produced by chlorination of simulated poultry chiller water . It is the second most potent mutagenic disinfection by-product of chlorination ever reported . Six of seven new synthetic analogs of this compound are direct-acting mutagens in Ames tester strain TA-100 . Computed energies of the lowest unoccupied molecular orbital (E(LUMO)) and of the radical anion stability (DeltaH(f)(rad)-DeltaH(f)) from MNDO-PM3 for the chloroimides show a quantitative correlation with the Ames TA-100 bacterial mutagenicity values . The molar mutagenicities of these direct acting mutagenic imides having an exocyclic double bond fit the same linear correlation (lnM(m) vs . E(LUMO); lnM(m) vs . DeltaH(f)(rad)--DeltaH(f)) as the chlorinated 2(5H)-furanones, including the potent mutagen MX, 3-chloro-4-(dichloro-methyl)-5-hydroxy-2(5H)-furanone, a by-product of water chlorination and paper bleaching with chlorine . Mutagenicity data for related haloimides having endocyclic double bonds are also given . For the same number of chlorine atoms, the imides with endocyclic double bonds have significantly higher Ames mutagenicity compared to their structural analogs with exocyclic double bonds, but do not follow the same E(LUMO) or DeltaH(f)(rad)-DeltaH(f) correlation as the exocyclic chloroimides and the chlorinated 2(5H)-furanones. Genome, 2001 Apr, 44(2), 154 - 62 Melon bacterial artificial chromosome (BAC) library construction using improved methods and identification of clones linked to the locus conferring resistance to melon Fusarium wilt (Fom-2); Luo M et al.; Utilizing improved methods, two bacterial artificial chromosome (BAC) libraries were constructed for the multidisease-resistant line of melon MR-1 . The HindIII library consists of 177 microtiter plates in a 384-well format, while the EcoRI library consists of 222 microtiter plates . Approximately 95.6% of the HindIII library clones contain nuclear DNA inserts with an average size of 118 kb, providing a coverage of 15.4 genome equivalents . Similarly, 96% of the EcoRI library clones contain nuclear DNA inserts with an average size of 114 kb, providing a coverage of 18.7 genome equivalents . Both libraries were evaluated for contamination with high-copy vector, empty pIndigoBac536 vector, and organellar DNA sequences . High-density filters were screened with two genetic markers FM and AM that co-segregate with Fom-2, a gene conferring resistance to races 0 and 1 of Fusarium wilt . Fourteen and 18 candidate BAC clones were identified for the FM and AM probes, respectively, from the HindIII library, while 34 were identified for the AM probe from filters A, B, and C of the EcoRI library. Appl Microbiol Biotechnol, 2001 Apr, 55(3), 348 - 53 Isolation and characterization of two aerobic bacterial strains that completely degrade ethyl tert-butyl ether (ETBE); Kharoune M et al.; Two bacterial strains, E1 and E2, isolated from gasoline-polluted soil completely degraded ethyl tert-butyl ether (ETBE), as the sole source of carbon and energy, at specific rates of about 80 mg g(-1) and 58 mg g(-1) of cell protein day(-1), respectively . On the basis of morphological and phenotypic characteristics, strain E1 was tentatively identified as Comamonas testosteroni and strain E2 as belonging to Centre for Disease Control group A-5 . The inhibitory effect of metyrapone on the degradative ability of both strains was the first evidence indicating the involvement of a soluble cytochrome P-450 in the cleavage of the ETBE ether bond . This observation was confirmed by spectrophotometric analysis of reduced cell extracts that gave, in the presence of carbon monoxide, a major absorbance peak at about 450 nm . Both strains were also able to degrade, as the sole source of carbon and energy, ETBE's major metabolic intermediates (tert-butyl alcohol and tert-butyl formate) and other gasoline oxygenates (methyl tert-butyl ether and tert-amyl methyl ether) . The degradation rates varied considerably, with both strains exhibiting a preferential activity for ETBE's metabolic intermediates. Cir Pediatr, 2001 Jan, 14(1), 4 - 8 {Effect of various trophic factors on bacterial translocation in experimental short bowel syndrome}; Eizaguirre I et al.; Massive bowel resection triggers an adaptive process in the remaining intestine in spite of which, bacterial translocation (BT) is frequent under these conditions . Several trophic factors, including growth hormone (GH), epidermal growth factor (EGF) and insuline (INS) are involved in the process of adaptation in short bowel syndrome (SBS) . However, the effect of GH, EGF or INS on BT has not been investigated experimentally . The aim of the study was to test the hypothesis that GH, EGF or INS administration prevents BT in rats with SBS receiving only parenteral nutrition (PN) . Thirty-seven adult Wistar rats underwent central venous cannulation and were randomly assigned to one of two groups receiving for ten days four treatment regimes: PN group (N = 10) fasting, all-in-one PN solution (300 mL/kg/24 h, 280 kcal/kg/24 h), 80% gut resection including ileo-cecal valve . GH group (N = 9) fasting, same PN regime and resection plus GH (1 mg/kg/d, s.c.) . EGF group (N = 9): same PN regime and resection plus EGF (150 microgr/24 h, e.v.) INS group(N = 9): same PN regime and resection plus INS (1 U.I./100 g/24 h s.c.) At the end of the experiment the rats were exanguinated and mesenteric lymph nodes and samples of systemic and portal blood were obtained and cultured . Several samples of full-thickness jejunal wall were taken for measuring cell proliferation index (PCNA) and mucosal thickness . Jejunal mucosal thickness increased by 30%, 28% and 29% and PCNA index by 21%, 20% and 25% in GH, EGF and INS, treated rats respectively in comparison with those treated with PN alone . However, contrary to our expectations, BT expressed by positive culture of intestinal germs in systemic blood was demonstrated respectively in 44%, 40% and 28% of GH, EGF and INS animals, respectively, and in 0% of PN-only rats . Although exogenous GH, EGF or INS improves gut mucosal structure in rats with SBS treated with PN, it seems to increase rather than decrease mucosal permeability to intestinal germs in them. Mikrobiologiia, 2001 Jan-Feb, 70(1), 128 - 34 {Features of cyanobacterial-bacterial complexes of microsymbionts of plant syncyanoses}; Dobakova ES et al.; The morphology and ultrastructure of associative microsymbiont complexes (AMC) isolated from the ferns Azolla pinnata and Azolla sp . and the apogeotropic roots of the cycad Cycas revoluta were studied . The composition of the AMC obtained includes the cyanobionts (symbiotic cyanobacteria) and satellite bacteria (SB) . It was found that two types of cyanobacteria that substantially differ in their morphological organization are likely present as cyanobionts in the coralloids of C . revoluta . The isolated cyanobiont strains exhibited the morphological traits and regularities of development typical of the genus Nostoc; they were characterized by the ability of their cells to divide in mutually perpendicular planes . When isolating AMC from different morphological zones of C . revoluta apogeotropic roots, SB growth was revealed only around the pieces corresponding to the coralloid apical zone . No AMC components were revealed around the segments of the basal growth zone . Pure cyanobiont cultures were obtained from the AMC of C . revoluta coralloids . The AMC isolated from the ferns A . pinnata and Azolla sp . are characterized by obligate mutual dependence of the partners (the cyanobiont and SB). Trends Microbiol, 2001 May, 9(5), 219 - 22 Model systems: Studying molecular recognition using bacterial n-hybrid systems; Hu JC; Since the first description of the yeast two-hybrid system, related genetic assays for protein-protein interactions have become popular and powerful tools for structure-function analysis on the scale of individual proteins or whole proteomes . After a somewhat surprising lag, similar systems have recently been described for use in bacterial hosts . n-hybrid modifications of the original yeast system have been used to examine interactions with DNA, RNA and small molecules, and other modifications have improved throughput for genomic applications . Bacterial n-hybrid systems are being designed for a similar array of uses . Will the bacterial systems be as popular as the yeast n-hybrid systems? Only time will tell. Int J Parasitol, 2001 May 1, 31(5-6), 621 - 7 Bacterial symbiosis and paratransgenic control of vector-borne Chagas disease; Beard CB et al.; The triatomine vectors of Chagas disease are obligate haematophagous insects, feeding on vertebrate blood throughout their entire developmental cycle . As a result of obtaining their nutrition from a single food source, their diet is devoid of certain vitamins and nutrients . Consequently, these insects harbour populations of bacterial symbionts within their intestinal tract, which provide the required nutrients that are lacking from their diet . We have isolated and characterised symbiont cultures from various triatomine species and developed a method for genetically transforming them . We can then reintroduce them into their original host species, thereby producing stable paratransgenic insects in which we are able to express heterologous gene products . Using this methodology, we have generated paratransgenic Rhodnius prolixus that are refractory for infection with Trypanosoma cruzi . Two examples of potentially refractory genes are currently being expressed in paratransgenic insects . These include the insect immune peptide cecropin A and active single chain antibody fragments . We have also developed an approach that would allow introduction of genetically modified bacterial symbionts into natural populations of Chagas disease vectors . This approach utilises the coprophagic behaviour of these insects, which is the way in which the symbionts are transmitted among bug populations in nature . The production and ultimate release of transgenic or paratransgenic insects for public health applications is potentially very promising but also worthy of much careful consideration with respect to environmental, political, and human safety concerns. Clin Nephrol, 2001 Apr, 55(4), 331 - 4 Right-sided non-bacterial thrombotic endocarditis in a chronic hemodialysis patient with Muir-Torre syndrome; Singhal S et al.; Endocarditis is a recognised complication ofhemodialysis . This is generally only thought of in terms of infective vegetations . We present a case of right-sided NBTE in a patient with an indwelling venous catheter who also had advanced pelvic malignancy . The unusual side of this patient's endocarditic lesions implicates a role for the venous catheter in determining the site of non-bacterial thrombus formation . It is also a reminder that endocarditis is always a risk when using central venous catheters, even after appropriate sterile precautions have been taken. Biochemistry (Mosc), 2001 Mar, 66(3), 319 - 22 Interaction of the bacterial ribonuclease binase with the polypeptide inhibitor barstar based on kinetic data on poly(U) hydrolysis; Yagodina LO; The reaction of poly(U) hydrolysis catalyzed by binase while the latter is inhibited by barstar has been investigated . The inhibition constant for barstar and the apparent Michaelis constants for the inhibition by barstar in the presence of ethanol and NaCl have been determined . Both ethanol and NaCl enhance the inhibition by barstar . This suggests that the binding of barstar with binase is probably due to the interaction of hydrophobic sites rather than by electrostatic interaction between amino acid residues. Biochemistry, 2001 Feb 13, 40(6), 1812 - 23 Equilibrium and kinetic parameters for the binding of inhibitors to the QB pocket in bacterial chromatophores: dependence on the state of QA; Ginet N et al.; The equilibrium and kinetic parameters for the binding of various inhibitors to the Q(B) pocket of the bacterial reaction center were investigated in chromatophores from Rhodobacter capsulatus and Rhodobacter sphaeroides . By monitoring the near-IR absorption changes specific to Q(A)(-) and Q(B)(-), we measured the fraction of inhibited centers in the dark and the kinetics and extent of inhibitor displacement after one flash due to the formation of the Q(A)Q(B)(-) state . The inhibitor release rate was much faster for triazines and o-phenanthroline (t(1/2) in the 50 ms to 1 s range) than for stigmatellin (t(1/2) approximately 20 s) . For inhibitors with a rapid release rate, the fast phase of P(+) decay observed in the absence of secondary donor reflects the competition between P(+)Q(A)(-) recombination and inhibitor release: it is thus faster than the P(+)Q(A)(-) recombination, and its relative extent is smaller than the fraction of initially inhibited centers . At appropriate inhibitor concentrations, one can have almost total binding in the dark and almost total inhibitor displacement after one flash . Under such conditions, a pair of closely spaced flashes resets the two-electron gate in a single state (Q(A)Q(B)(-)), irrespective of the initial state . The apparent dissociation constant of terbutryn was significantly increased (by a factor of 4-7) in the presence of Q(A)(-), in agreement with the conclusion of Wraight and co-workers {Stein, R . R., et al . (1984) J . Cell . Biochem . 24, 243-259} . We suggest that this effect is essentially due to a tighter binding of ubiquinone in the Q(A)(-) state. IUBMB Life, 2000 Dec, 50(6), 385 - 90 Interaction of bacterial flagellum filaments with skeletal muscle myosin; Novikova NA et al.; Interaction of isolated bacterial flagellum filaments (BFF) and intact flagella from E . coli MS 1350 and B . brevis G.-B.p+ with rabbit skeletal myosin was studied . BFF were shown to coprecipitate with myosin (but not with isolated myosin rod) at low ionic strength, that is, under conditions of myosin aggregation . The data of electron microscopy indicate that filaments of intact bacterial flagella interact with isolated myosin heads (myosin subfragment 1, S1), and this interaction is fully prevented by addition of Mg2+ -ATP . Addition of BFF inhibited both K+ -EDTA- and Ca2+ -ATPase activity of skeletal muscle myosin, but had no effect on its Mg2+ -ATPase activity . Monomeric flagellin did not coprecipitate with myosin and had no effect on its ATPase activities . BFF were shown to compete with F-actin in myosin binding . It is concluded that BFF interact with myosin heads and affect their ATPase activity . Thus, BFF composed of a single protein flagellin are in many respects similar to actin filaments . Common origin of actin and flagellin may be a reason for this similarity. Int Dent J, 2001 Feb, 51(1), 39 - 44 Bacterial aerosols in the dental clinic: a review; Leggat PA et al.; A number of sources of bacterial aerosols exist within and outside the dental clinic . The concentration of bacterial aerosols and splatters appears to be highest during dental procedures, especially those generated by some procedures such as ultrasonic scaling, or using a high speed drill . Several infectious diseases could be transmitted to staff and patients by airborne bacterial and other contaminants in the dental clinic . Air-conditioning and ventilation systems should be regularly maintained to reduce environmental contaminants and to prevent recirculation of bacterial aerosols . Pre-procedural rinsing by patients with mouthwashes as well as vacuum and electrostatic extraction of aerosols during dental procedures could also be employed . Dental staff should also consider appropriate immunizations and continue to use personal protective measures, which reduce contact with bacterial aerosols and splatters in the dental clinic. J Clin Microbiol, 2001 May, 39(5), 1956 - 9 Does blood of healthy subjects contain bacterial ribosomal DNA? Nikkari S, McLaughlin IJ, Bi W, Dodge DE, Relman DA. Real-time PCR methods with primers and a probe targeting conserved regions of the bacterial 16S ribosomal DNA (rDNA) revealed a larger amount of rDNA in blood specimens from healthy individuals than in matched reagent controls . However, the origins and identities of these blood-associated bacterial rDNA sequences remain obscure. FEMS Microbiol Lett, 2001 Apr 20, 198(1), 65 - 71 Analysis of mutational effects of a polyhydroxybutyrate (PHB) polymerase on bacterial PHB accumulation using an in vivo assay system; Taguchi S et al.; Polymerase is a central enzyme involved in the biosynthesis of polyhydroxybutyrate (PHB), a well-known bacterial biodegradable polyester . In this study, we have established an in vivo assay system to analyze mutational effects of Ralstonia eutropha polymerase (termed PhbC(Re)) on the level of PHB accumulation in recombinant strains of Escherichia coli . This in vitro evolution system consists of a polymerase chain reaction-mediated random mutagenesis and two assay procedures, a plate assay using a PHB-staining dye and a high-pressure liquid chromatographic assay based on the converting reaction from PHB to crotonic acid . The distribution pattern of the PHB accumulation level of the mutant population using 378 clones arbitrarily selected, suggested that the present level of PhbC(Re) is high and well-optimized . It is noteworthy that many of the amino acid substitutions affecting the PHB accumulation occurred in the conserved positions or regions within an 'alpha/beta hydrolase fold' which is commonly found among hydrolytic enzymes . From a good correlation with the level of PHB accumulation, an activity estimation of the PhbC(Re) would be efficiently achieved by monitoring the level of PHB accumulation using the in vivo assay system established here. J Laryngol Otol, 2001 Feb, 115(2), 101 - 5 Bacterial coating with immunoglobulins on the palatine tonsils during infectious mononucleosis: immunocytochemical study with gold markers; Stenfors LE et al.; Epithelial cells and bacteria were sampled from the tonsillar surfaces of seven patients (six males, one female; median age 16 years, range 10 to 21 years) suffering from acute infectious mononucleosis with concomitant pharyngotonsillitis . By using gold-labelled antiserum to human IgG and secretory IgA (sIgA), micro-organisms on the tonsillar surfaces coated with these immunoglobulins could be identified by tracing the gold particles in the transmission electron microscope . The patients harboured significantly fewer bacteria coated with immunoglobulins than did healthy controls . More bacteria were coated with IgG immunoglobulins than with sIgA . Reduced immunoglobulin-coating of the bacteria on the tonsillar surfaces during infectious mononucleosis can explain their tendency to immense local colonization and proneness to penetrate into the epithelial cells. Biotechnol Bioeng, 2001 Jun 5, 73(5), 400 - 5 Fluorescent detection of cyanobacterial DNA using bacterial magnetic particles on a MAG-microarray; Matsunaga T et al.; Bacterial magnetic particles (BMPs) were used for the identification of cyanobacterial DNA . Genus-specific oligonucleotide probes for the detection of Anabaena spp., Microcystis spp., Nostoc spp., Oscillatoria spp., and Synechococcus spp . were designed from the variable region of the cyanobacterial 16S rDNA of 148 strains . These oligonucleotide probes were immobilized on BMPs via streptavidin-biotin conjugation and employed for magnetic-capture hybridization against digoxigenin-labeled cyanobacterial 16S rDNA . Bacterial magnetic particles were magnetically concentrated, spotted in 100-microm-size microwell on MAG-microarray, and the fluorescent detection was performed . This work details the development of an automated technique for the magnetic isolation, the concentration of hybridized DNA, and the detection of specific target DNA on MAG-microarray . The entire process of hybridization and detection was automatically performed using a magnetic-separation robot and all five cyanobacterial genera were successfully discriminated . Panminerva Med, 2001 Mar, 43(1), 11 - 4 The influence of somatostatin on bacterial translocation; Tocchi A et al.; BACKGROUND: Bacterial translocation is defined as the passage of bacteria from the gastrointestinal tract to extraintestinal sites mostly as a consequence of the loss of the gut barrier function . Somatostatin and octreotide, exerting many inhibitory effects on the gastrointestinal tract, have been evidenced to promote bacterial translocation . METHODS: Design: experimental research . Setting: University teaching Hospital . Interventions: Sixteen pigs forming the study group received 25 mg/kg of octreotide twice a day for ten days . A control group (n=16) received an equal volume of saline solution for the same period . All animals were sacrificed and tissue cultures were obtained from mesenteric lymph nodes (MLN), liver and spleen . Portal venous and central venous blood samples were also withdrawn for culture . RESULTS: In the octreotide group, cultures were positive for bacteria in 43.7% (7/16) of animals . Viable bacteria were recovered from MLN, liver and spleen . Portal and systemic blood cultures showed no growth of bacteria . The mean value of bacterial detection in MLN, liver and spleen was 196+/-13 CFU/g, 190+/-26 CFU/g, and 173+/-0 CFU/g, respectively . P value was not statistically significant . Bacterial translocation did not occur in the animals of the control group . Fisher s exact test revealed a statistically significant difference (p<0.007) between the two groups regarding bacterial translocation to MLN . CONCLUSIONS: The administration of octreotide is followed by a conspicuous increase in bacterial translocation in pigs . Further clinical studies are needed to demonstrate similar effects on humans. Sex Transm Dis, 2001 Apr, 28(4), 195 - 9 Prevalence of Mobiluncus spp among women with and without bacterial vaginosis as detected by polymerase chain reaction; Schwebke JR et al.; BACKGROUND: Mobiluncus spp are highly associated with bacterial vaginosis, but their role in its pathogenesis is unknown . The authors used polymerase chain reaction (PCR) to compare the prevalence of Mobiluncus in women with and without bacterial vaginosis . GOAL: To compare the prevalence of Mobiluncus spp among women with and without bacterial vaginosis and to compare the sensitivities of PCR and Gram stain for detection . STUDY DESIGN: Vaginal specimens from 74 women were analyzed by PCR and Gram stain for the presence of Mobiluncus spp . Comparisons were made between the prevalence of this organism between the two cohorts and between the Gram stain and PCR detection methods . RESULTS: Mobiluncus was detected by PCR in 84.5% of women with bacterial vaginosis and in 38% of women without infection . M curtisii was rarely detected in the latter group, though it was found in 65.3% of women with bacterial vaginosis . The sensitivity and specificity of Gram stain compared with PCR were 46.9% and 100%, respectively . CONCLUSIONS: Mobiluncus is more common in healthy women than previously suspected, with M mulieris as the predominant species . The significant difference in the prevalence of M curtisii between women with bacterial vaginosis and uninfected women suggests that this species could be involved in the pathogenesis of bacterial vaginosis. Am J Gastroenterol, 2001 Apr, 96(4), 1232 - 6 Spontaneous bacterial peritonitis--in-hospital mortality, predictors of survival, and health care costs from 1988 to 1998; Thuluvath PJ et al.; OBJECTIVES: Spontaneous bacterial peritonitis (SBP) is a complication of end-stage liver disease with a reported mortality of 30-50% . In this study, we investigated the outcome of all patients admitted to Maryland hospitals with SBP from 1988 to 1998 . Main outcomes considered included trends in survival rates over time, changes in the length of stay, total health care costs, and variables that predicted survival rates . METHODS: We used the Maryland Health Services Cost Review database of all patients admitted to Maryland hospitals with an International Classification of Diseases (Ninth Revision) code for both peritonitis and cirrhosis from 1988 to 1998 . RESULTS: A total of 348 patients were admitted with an in-hospital mortality of 32.6%; there was no significant change in mortality rate during this period . The survival rate was similar in the university and community hospitals . In the logistic regression analysis, age (p = 0.001) and intensive care unit stay (p = 0.0001) were found to significantly influence the survival rates; those patients who had an intensive care unit stay were 2.8 times more likely to die than those who did not have an intensive care unit stay, controlling for age . The average length of hospital stay remained unchanged (13.5 +/- 12.7 days) during the study period . Although the median hospital charge (excluding professional fees) remained unchanged, mean inflation-adjusted charges increased from $7,897 in 1988 to $25,902 in CONCLUSIONS: The mortality rate associated with SBP has remained unchanged over an 11-yr period from 1988 to 1998 . The mortality showed a strong correlation with age and intensive care unit stay . The median hospital stay and median charges remained unchanged during this period, but mean costs increased significantly because of increased use of resources by a few patients. Cell Mol Life Sci, 2001 Mar, 58(3), 403 - 19 Transposase and cointegrase: specialized transposition proteins of the bacterial insertion sequence IS21 and related elements; Berger B et al.; The bacterial insertion sequence IS21 shares with many insertion sequences a two-step, reactive junction transposition pathway, for which a model is presented in this review: a reactive junction with abutted inverted repeats is first formed and subsequently integrated into the target DNA . The reactive junction occurs in IS21-IS21 tandems and IS21 minicircles . In addition, IS21 shows a unique specialization of transposition functions . By alternative translation initiation, the transposase gene codes for two products: the transposase, capable of promoting both steps of the reactive junction pathway, and the cointegrase, which only promotes the integration of reactive junctions but with higher efficiency . This review also includes a survey of the IS21 family and speculates on the possibility that other members present a similar transpositional specialization. FEMS Microbiol Lett, 2001 Apr 13, 197(2), 131 - 8 Glycosylphosphatidylinositol-anchored receptor-mediated bacterial endocytosis; Shin JS et al.; An increasing number of pathogens or their toxins appear to utilize glycosylphosphatidylinositol(GPI)-anchored receptors to trigger entry into immune and other host cells . Since these receptors have no transmembrane and intracellular moieties, how endocytosis is initiated is unclear . Recently, CD48 on mast cell membranes was shown to trigger endocytosis of bacteria via a route that avoids fusion with lysosomes and by a mechanism involving discrete cellular entities called caveolae . The localization of CD48 within caveolae appears to be a prerequisite for caveolae-mediated bacterial entry. Prog Biophys Mol Biol, 2001, 75(1-2), 1 - 17 Self-organisation and orderly processes by individual protein complexes in the bacterial cell; Kuthan H; In the bacterial cell, individual multimeric proteins and multiprotein assemblies perform and control orderly processes . Individual motor enzyme complexes accomplish highly complex functions, such as nucleic acid and protein syntheses, with impressive efficiency and fidelity . Lac operon repression by the lac repressor is effectively controlled via a single molecular switch . There are only few copies of, for example, DNA polymerase holoenzyme and lac repressor and few specific target molecules/sites, with which these protein complexes interact, present in a single E . coli cell . These interactive processes take place in submicron-sized spaces characterised by extreme crowding (volume exclusion) of macromolecules and small molecules, heterogeneity and non-ideality . Recent evidence reinforces the fundamental difference of the cytoplasmic as compared with in vitro ("test tube") reaction conditions . This is reflected in the breakdown of the applicability of "bulk phase" thermodynamic, macroscopic chemical kinetic and diffusion laws to interactions of individual macromolecules and target sites in a single cell . Stochastic kinetic models and stochastic simulations enable the statistical description and analysis of biochemical reactions and binding processes which involve small numbers of reactants . New unifying concepts and models are required for the quantitative understanding of the microscopic self-organisation of multi-protein complexes and the dynamic order at the single-protein assembly and single-switch level in the living cell. Gene, 2001 Apr 4, 267(1), 125 - 34 Identification and characterization of a human mitochondrial homologue of the bacterial co-chaperone GrpE; Choglay AA et al.; We have identified a novel human cDNA with a predicted protein sequence that has 28% amino acid identity with the E . coli Hsp70 co-chaperone GrpE and designated it HMGE . Even with this low level of amino acid identity the human sequence could be efficiently modelled on the X-ray structure of the E . coli protein, suggesting that there may be significant functional conservation . Indeed, HMGE expressed in E . coli as a GST fusion protein co-purified with the E . coli Hsp70 protein DnaK in the absence of ATP . DnaK could be released from the GST-HMGE with a Mg-ATP wash . Subcellular fractionation and immunocytochemistry studies using antisera raized against HMGE show that it is a mitochondrial protein . In contrast to studies of rat GrpE, however, HMGE also appears to bind the constitutive cytosolic Hsp70, Hsc70, in addition to mitochondrial Hsp70, Mt-Hsp70 . We have previously shown that Hsc70 nucleotide-exchange is rate limiting in the presence of the DnaJ-protein, HSJ1b . However, HMGE was found to inhibit the HSJ1b-enhanced Hsc70 ATPase activity and may mediate this inhibition by binding the DnaJ-protein, HSJ1b . This is the first description of a direct interaction between a DnaJ protein and GrpE-like protein . These studies suggest that the structure of GrpE has been conserved throughout evolution and that the conserved structure can interact with several forms of Hsp70, but that HMGE cannot form part of the reaction cycle for cytosolic Hsc70. J Leukoc Biol, 2001 Apr, 69(4), 590 - 7 Induction of soluble antitumoral mediators by synthetic analogues of bacterial lipoprotein in bone marrow-derived macrophages from LPS-responder and -nonresponder mice; Pfannes SD et al.; Macrophage-dependent antitumoral activity is partly mediated by soluble factors including cytokines, reactive-oxygen intermediates (ROIs), and reactive-nitrogen intermediates (RNIs) . Activation of macrophages for tumor cytotoxicity can be achieved with various bacterial compounds, such as lipopolysaccharides (LPSs), muramyl-dipeptides, and lipopeptides . We studied the production and release of oxygen radicals, nitric oxide, and tumor necrosis factor alpha (TNF-alpha) by bone marrow-derived macrophages (BMDMs) of different mouse inbred strains after they were stimulated with the lipopeptide P3CSK4, a water-soluble synthetic analogue of the lipidated N terminus of bacterial lipoprotein . The lipopeptide was able to induce a strong, long lasting release of oxygen radicals in BALB/c mouse macrophages . Furthermore, it induced nitric oxide release from BMDMs of several mouse strains (BALB/c, C57Bl/6, C57Bl/10ScSn, Sv129, NMRI, and LPS-nonresponder C57Bl/10ScCr) . Stimulation with P3CSK4 also resulted in comparable production of TNF-alpha in LPS-responder and nonresponder BMDMs from C57Bl/10ScSn mice and C57Bl/10ScCr mice, respectively . All three antitumoral mediators reached functional levels or concentrations as shown by the strong cytostatic/cytotoxic activity of lipopeptide-activated macrophages for the cell lines Abelson 8-1, M12.5/P815, and L929, which are sensitive to ROIs, nitric oxide, and TNF-alpha, respectively . We found that synthetic lipopeptides can induce the secretion of effective levels of soluble tumor-cytotoxic/cytostatic mediators in BMDMs of LPS-responsive and, of particular interest, also of LPS-unresponsive mice . This result could indicate that the highly effective bacterial-macrophage activators P3CSK4 and LPS use different receptors and/or different intracellular signal transduction pathways. Mamm Genome, 2001 Apr, 12(4), 261 - 71 The battle of two genomes: genetics of bacterial host/pathogen interactions in mice; Lengeling A et al.; Genetic factors strongly determine the outcome of infectious diseases caused by various pathogens . The molecular mechanisms of resistance and susceptibility in humans, however, remains largely unknown . Complex interactions of multiple genes that control the host response to a pathogen further complicate the picture . Animal models have a tremendous potential to dissect the complex genetic system of host-pathogen interaction into single components . This is particularly true for the mouse, which will continue to develop into an invaluable tool in the identification and cloning of host resistance genes . Three main approaches have been taken to establish mouse models for human infectious diseases: 1) Production of mouse mutants by gene targeting; 2) positional cloning of host-resistance genes in mutant mice; and 3) mapping and characterization of quantitative trait loci (QTL) controlling the complex aspects of host-pathogen interactions . The contribution of all three methods to the understanding of infectious diseases in humans will be reviewed in this work, with a special emphasis on the studies of resistance/susceptibility mechanism in bacterial infections. J Biol Chem, 2001 Jun 22, 276(25), 23018 - 27 Epub 2001 Apr 13. An araC-controlled bacterial cre expression system to produce DNA minicircle vectors for nuclear and mitochondrial gene therapy; Bigger BW et al.; The presence of CpG motifs and their associated sequences in bacterial DNA causes an immunotoxic response following the delivery of these plasmid vectors into mammalian hosts . We describe a biotechnological approach to the elimination of this problem by the creation of a bacterial cre recombinase expression system, tightly controlled by the arabinose regulon . This permits the Cre-mediated and -directed excision of the entire bacterial vector sequences from plasmid constructs to create supercoiled gene expression minicircles for gene therapy . Minicircle yields using standard culture volumes are sufficient for most in vitro and in vivo applications whereas minicircle expression in vitro is significantly increased over standard plasmid transfection . By the simple expedient of removing the bacterial DNA complement, we significantly reduce the size and CpG content of these expression vectors, which should also reduce DNA-induced inflammatory responses in a dose-dependent manner . We further describe the generation of minicircle expression vectors for mammalian mitochondrial gene therapy, for which no other vector systems currently exist . The removal of bacterial vector sequences should permit appropriate transcription and correct transcriptional cleavage from the mitochondrial minicircle constructs in a mitochondrial environment and brings the realization of mitochondrial gene therapy a step closer. Phys Rev E Stat Nonlin Soft Matter Phys . 2001 Jan;63(1 Pt 1):011906 . Epub 2000 Dec 21. Extinction of a bacterial colony under forced convection in pie geometry; Shnerb NM; The extinction of a bacterial colony, as it is forced to migrate into a hostile environment, is analyzed in pie geometry . Under convection, separation of the radial and the azimuthal degrees of freedom is not possible, so the linearized evolution operator is diagonalized numerically . Some characteristic scales are compared with the results of recent experiments, and the "integrable" limit of the theory in the narrow growth region is studied. Shock, 2001 Apr, 15(4), 307 - 11 Influence of hypertonic saline on bacterial translocation in controlled hemorrhagic shock; Assalia A et al.; Translocation of enteric bacteria has been described in rats following hemorrhagic shock (HS) . The aim of the present study was to evaluate the effect of hypertonic saline (HTS) on bacterial translocation (BT) in the setting of controlled HS in rats . The study included 2 arms . Arm I was a qualitative assessment of translocation . Sixty-eight anesthetized animals were studied . The rats were divided into 5 groups . Group I (n = 10) was sham shock controls . In groups II-V, HS was induced by arterial bleeding to mean arterial pressure (MAP) of 35-45 mmHg, which was maintained for 30 min . The animals were then allocated into 4 groups: group II (n = 19) untreated HS; group III (n = 13) normal saline (NS) treated; group IV (n = 13) HTS-treated; and group V (n = 13) HTS and blood treated . Mesenteric lymph nodes, liver, spleen, portal, and systemic blood were sent for culture after 24 h . Translocation occurred if enteric bacteria were cultured from at least one site . Arm II was a quantitative assessment of translocation . Two groups were studied: untreated HS (n = 7) and HTS treated (n = 6) . In the qualitative arm, the 24-h mortality in untreated rats (group II) was 31.5% compared to 5.1% in treated animals (groups II-V) (P = 0.01) . No BT was detected in control animals (group I) . BT after HS was not different between groups II, III, and IV (92.3%, 91.6%, and 100%, respectively) . Group V showed fewer translocations than groups II-IV, a difference that was especially significant compared with group IV (P = 0.039) . However, BT to distant sites (systemic blood and spleen) was significantly lower in group V than in groups II-IV (P < 0.05) . In the quantitative arm, the mortality rate was 16.7% in the untreated group . Although no qualitative significant difference in the translocation rate was found between the two groups (67% in untreated animals vs . 50% in HTS treated), there was significant quantitative difference: in HTS-treated group a significantly lesser bacteria translocated than in untreated animals (0.4 x 10(5) cfu/g vs . 4.2 x 10(5) cfu/g, respectively {P = 0.001}) . We concluded that whereas assessed qualitatively, in this model of severe HS in rats, the hemorrhagic insult itself resulted in BT in most animals and treatment with NS, HTS, and blood resulted in reduced early mortality but did not alter significantly the translocation rate . Only the combination of HTS and blood resulted in reduced BT to distant sites . However, quantitative assessment showed that HTS significantly reduced the number of translocating bacteria. Antimicrob Agents Chemother, 2001 May, 45(5), 1547 - 9 Thalidomide inhibits granulocyte responses in healthy humans after ex vivo stimulation with bacterial antigens; Juffermans NP et al.; Ingestion of thalidomide was associated with a reduction in the upregulation of the granulocyte activation marker CD11b and a reduced capacity to release elastase and lactoferrin after stimulation with lipopolysaccharide or lipoteichoic acid . A single oral dose of thalidomide attenuates neutrophil activation upon ex vivo stimulation with bacterial antigens. Microsc Res Tech, 2001 May 1, 53(3), 188 - 92 The trigeminovascular system in bacterial meningitis; Hoffmann O et al.; Headache as a cardinal symptom of acute meningitis reflects activation of trigeminal afferents from the meninges . With their perivascular endings, these fibers form the so-called trigeminovascular system (TVS), which releases proinflammatory neuropeptides upon nociceptive stimulation . In the present article, we review a role of the TVS in enhancing the early inflammatory response of bacterial meningitis . Furthermore, we discuss inhibition of neuropeptide release from the TVS using 5HT(1B/D) agonists as a potential new anti-inflammatory treatment strategy for early bacterial meningitis . Eur J Clin Invest, 2001 Apr, 31(4), 285 - 92 Comparative study on antibodies to human and bacterial 60 kDa heat shock proteins in a large cohort of patients with coronary heart disease and healthy subjects; Prohaszka Z et al.; BACKGROUND: Recent observations indicate an association between antibodies against mycobacterial heat shock protein (hsp65) and coronary heart disease (CHD) . Previously, we reported on marked differences in antigen specificity and complement activating ability of anti-hsp65 antibodies and auto-antibodies against human heat shock protein, hsp60 . Here, we investigated whether there are differences between antih-sp65 and anti-hsp60 antibodies in their association with CHD . DESIGN: We measured by ELISA the levels of antibodies to hsp65, hsp60 and E . coli-derived GroEL in three groups: Group I, 357 patients with severe CHD who underwent by-pass surgery; Group II, 67 patients with negative coronary angiography; Group III, 321 healthy blood donors . Antibodies against Helicobacter pylori were also measured by commercial ELISA . RESULTS: As calculated by multiple regression analysis, the levels of anti-hsp60 auto-antibodies were significantly higher in Group I compared to Group II (P = 0.007) or Group III (P < 0.0001) . By contrast, although concentrations of anti-hsp65 and anti-GroEL antibodies in Group I were higher than in Group III, no significant differences between Group I and Group II were found . Antibodies to the two bacterial hsp strongly correlated to each other, but either did not correlate or weakly correlated to hsp60 . In Group I, serum concentrations of anti-H.pylori antibodies significantly correlated with those of anti-hsp65 and anti-GroEL antibodies but they did not correlate with the anti-hsp60 antibodies . CONCLUSIONS: As to their clinical relevance, a remarkable difference become evident between antibodies to human hsp60 and antibodies against bacterial hsp in the extent of association with CHD . On the basis of these findings and some pertinent literature data, an alternative explanation for the association between high level of anti-hsp antibodies and atherosclerotic vascular diseases is raised. Clin Microbiol Infect, 2001 Feb, 7(2), 80 - 3 Tick-borne bacterial diseases emerging in Europe; Parola P et al.; Since the identification of Borrelia burgdorferi as the agent of Lyme disease in 1982, 11 tick-borne human bacterial pathogens have been described throughout Europe . These include five spotted fever rickettsiae, the agent of human granulocytic ehrlichiosis, four species of the B . burgdorferi complex and a new relapsing fever borrelia . We present these emerging diseases and focus on the factors that play a role in the recognition of new tick-borne diseases. Curr Opin Struct Biol, 2001 Apr, 11(2), 155 - 62 Bacterial RNA polymerase; Darst SA; The recently determined crystal structure of a bacterial core RNA polymerase (RNAP) provides the first glimpse of this family of evolutionarily conserved cellular RNAPs . Using the structure as a framework, a consistent picture of protein-nucleic acid interactions in transcription complexes has been accumulated from cross-linking experiments . The molecule can be viewed as a molecular machine, with distinct structural features hypothesized to perform specific functions . Comparison with the alpha-carbon backbone of a eukaryotic RNAP reveals close structural similarity. Eur J Epidemiol, 2000, 16(9), 843 - 8 Estimating incidence of bacterial meningitis with capture-recapture method, Lazio Region, Italy; Faustini A et al.; To estimate the incidence of bacterial meningitis in the Lazio Region, including the city of Rome, and to assess the quality of the surveillance systems, we adopted a multiple-capture model by merging cases from three sources available in 1995-1996: the Notifiable Disease Surveillance (NDS) system, the Special Hospital Surveillance (SHS) system and the Hospital Discharge (HD) registry . A medical record revision was carried out to confirm the cases of bacterial meningitis . A total of 199 individuals was classified as probable or confirmed cases of bacterial meningitis in 1995-1996 . In this period, the incidence of reported meningitis was 3.8/100,000 (population = 5,209,633) . The log-linear model yielded a total estimated number of 236 cases (95% confidence interval (CI): 206-306), the estimate of incidence reaching the value of 4.5/100,000 . Hospital Discharge registry showed the highest sensitivity (77%), the SHS system the highest positive predictive value (83%) . In 1997-1998, the meningitis surveillance was integrated with an additional laboratory-based source and yielded 326 cases, with an incidence of reported cases of 6.3/100,000 . Laboratory surveillance, involving 115 (92%) public hospitals and 84 (57%) private clinics, contributed 35 (27%) cases in addition to those notified to NDS (n = 130) . Multiple-capture models, in our experience could estimate the bacterial meningitis incidence with a very good approximation . In order to improve both sensitivity and positive predictive value of surveillance, hospital and public health sources should be integrated with laboratory-based system. Keio J Med, 2001 Mar, 50(1), 26 - 30 The development and applications of the bacterial artificial chromosome cloning system; Shizuya H et al.; The development of the Bacterial Artificial Chromosome (BAC) system was driven in part by the Human Genome Project as a means to construct genomic DNA libraries and physical maps for genomic sequencing . The BAC system is based on the well-characterized Escherichia coli F-factor, a low copy plasmid that exists in a supercoiled circular form in host cells . The structural features of the F-factor allow stable maintenance of individual human DNA clones as well as easy manipulation of the cloned DNA . BACs are currently used in a wide array of applications from genome sequencing to gene discovery . This paper describes the key elements in the development of the BAC system and its current notable applications. EMBO J, 2001 Apr 17, 20(8), 1819 - 28 Structural and functional studies of MinD ATPase: implications for the molecular recognition of the bacterial cell division apparatus; Hayashi I et al.; Proper placement of the bacterial cell division site requires the site-specific inactivation of other potential division sites . In Escherichia coli, selection of the correct mid-cell site is mediated by the MinC, MinD and MinE proteins . To clarify the functional role of the bacterial cell division inhibitor MinD, which is a membrane-associated ATPase that works as an activator of MinC, we determined the crystal structure of a Pyrococcus furiosus MinD homologue complexed with a substrate analogue, AMPPCP, and with the product ADP at resolutions of 2.7 and 2.0 A, respectively . The structure reveals general similarities to the nitrogenase iron protein, the H-Ras p21 and the RecA-like ATPase domain . Alanine scanning mutational analyses of E.coli MinD were also performed in vivo . The results suggest that the residues around the ATP-binding site are required for the direct interaction with MinC, and that ATP binding and hydrolysis play a role as a molecular switch to control the mechanisms of MinCDE-dependent bacterial cell division. Trends Biochem Sci, 2001 Apr, 26(4), 257 - 65 Transmembrane signaling in bacterial chemoreceptors; Falke JJ et al.; Bacterial chemoreceptors mediate chemotaxis by recognizing specific chemicals and regulating a noncovalently associated histidine kinase . Ligand binding to the external domain of the membrane-spanning receptor generates a transmembrane signal that modulates kinase activity inside the cell . This transmembrane signaling is being investigated by novel strategies, which have revealed a remarkably subtle conformational signal carried by a signaling helix that spans the entire length of the >350-A-long receptor . Multiple, independent lines of evidence indicate that, in the periplasmic and transmembrane domains, conformational signaling is a piston-type sliding of the signaling helix towards the cytoplasm. FEMS Microbiol Ecol, 2001 Apr, 35(2), 171 - 179 Are the actively respiring cells (CTC+) those responsible for bacterial production in aquatic environments? Servais P, Agogue H, Courties C, Joux F, Lebaron P. The 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) staining method is commonly and increasingly used to detect and to enumerate actively respiring cells (CTC+ cells) in aquatic systems . However, this method remains controversial since some authors promote this technique while others pointed out several drawbacks of the method . Using flow cytometry (FCM), we showed that CTC staining kinetics vary greatly from one sample to another . Therefore, there is no universal staining protocol that can be applied to aquatic bacterial communities . Furthermore, using (3)H-leucine incorporation, it was shown that the CTC dye has a rapid toxic effect on bacterial cells by inhibiting protein synthesis, a key physiological function . The coupling of radioactive labelling with cell sorting by FCM suggested that CTC+ cells contribute to less than 60% of the whole bacterial activity determined at the community level . From these results, it is clearly demonstrated that the CTC method is not valid to detect active bacteria, i.e . cells responsible for bacterial production. FEMS Microbiol Ecol, 2001 Apr, 35(2), 123 - 128 Phylogenetic characterization of the blue filamentous bacterial community from an Icelandic geothermal spring; Takacs CD et al.; Molecular phylogenetic analysis of a blue filamentous community from an alkaline thermal spring (79-83 degrees C) in Iceland revealed that the blue filaments were affiliated with the Aquificales . The dominant sequence type, pIce1, was most closely related to a sequence (SRI-48) found in a white filamentous community from a separate Icelandic thermal spring and the pink filaments (EM17) from Yellowstone National Park . Fluorescent in situ hybridization with clone-specific oligonucleotide probes showed that the sample analyzed was essentially a monoculture of a single phylotype. Am J Physiol Regul Integr Comp Physiol, 2001 May, 280(5), R1356 - 63 Differential expression of uterine NO in pregnant and nonpregnant rats with intrauterine bacterial infection; Fang L et al.; Previous studies have demonstrated that nitric oxide (NO) is involved in the uterine host defense against bacterial infection . In nonpregnant rats, NO production in the uterus was shown to be lower, and inducible NO synthase (NOS) expression was undetectable . However, studies in pregnant rats show abundant expression of inducible NOS with significant elevation in NO production in the uterus . We have recently reported that intrauterine Escherichia coli infection caused a localized increase in uterine NO production and inducible NOS expression in the nonpregnant rat . In our present study, we examined whether the uterine NO production, NOS expression, and uterine tumor necrosis factor-alpha protein are increased in pregnant rats with intrauterine pathogenic Escherichia coli infection . Unlike the nonpregnant state, the NO production in the infected uterine horn of pregnant rats was not significantly elevated after bacterial inoculation compared with the contralateral uterine horn . The expression of uterine NOS (types II and III) also did not show significant upregulation in the infected horn . This is in contrast to that in nonpregnant animals, in which type II NOS was induced in the uterus on infection . Moreover, intrauterine infection induced an elevated expression of tumor necrosis factor-alpha protein in the infected horn both of nonpregnant and of pregnant rats . These data suggest that the sequential stimulation of NOS expression, especially the inducible isoform, and generation of uterine NO are lacking during pregnancy despite an elevated tumor necrosis factor-alpha after infection . In summary, NO synthesis response may be maximal at pregnancy, and infection may not further induce the NO system . Present studies, together with our previous report that intrauterine infection-induced lethality in pregnancy rats was amplified with the inhibition of NO, suggest that pregnancy is a state predisposed for increased complications associated with intrauterine infection and that the constitutively elevated uterine NO during pregnancy may help contain or even reduce the risk of infection-related complications. Infect Immun, 2001 May, 69(5), 2972 - 9 Specific antibodies to Porphyromonas gingivalis Lys-gingipain by DNA vaccination inhibit bacterial binding to hemoglobin and protect mice from infection; Kuboniwa M et al.; Lys-gingipain (KGP), a lysine-specific cysteine proteinase, is one of the major virulence factors of Porphyromonas gingivalis . Here we examined the involvement of the catalytic domain of KGP (KGP(cd)) in hemoglobin binding by P . gingivalis, using a specific immunoglobulin G (IgG) elicited by the administration of plasmid DNA encoding KGP(cd) or the catalytic domain of Arg-gingipain (RGP(cd)) . The pSeq2A/kgp(cd) and pSeq2B/rgp(cd) plasmids were constructed by the ligation of kgp(cd) and rgp(cd) DNA fragments, respectively . Female BALB/c mice were immunized with each of these plasmids . pSeq2A/kgp(cd) elicited a strong response to recombinant KGP(cd) (rKGP(cd)), as well as to comparably produced rRGP(cd)-reactive antibodies . The serum antibodies elicited by pSecTag2B/rgp(cd) also cross-reacted with rKGP(cd) as well as rRGP(cd) . Anti-KGP(cd) IgG significantly inhibited hemoglobin binding by P . gingivalis . Furthermore, the inhibition of hemoglobin binding was markedly enhanced by a combination of anti-KGP(cd) and anti-fimbriae . Anti-RGP(cd) IgG showed a negligible inhibitory effect, while both anti-KGP(cd) and anti-RGP(cd) IgGs showed significant inhibitory effects on Lys- and Arg-specific proteolytic activities and on the growth of P . gingivalis under iron-restricted conditions where supplemented hemoglobin was the sole iron source . Immunized mice were challenged by intraperitoneal inoculation with P . gingivalis . All nonimmunized mice died within 72 h; however, vaccination with pSeq2A/kgp(cd) and pSeq2B/rgp(cd) prevented inflammatory responses and prolonged the survival rate of immunized mice by 43 and 27%, respectively . These results suggest that KGP(cd) acts as a hemoglobin-binding protein and can also be useful as an immunogen inducing a protective response to P . gingivalis infection. Biotechnol Bioeng, 2000-2001, 71(4), 255 - 65 Modeling, simulation, and optimization of bacterial leaching reactors; Crundwell FK; Bacterial leaching represents an unusual problem in biochemical engineering, because the substrate for bacterial growth is not supplied directly, but is a product of another reaction, the leaching of mineral particles . In addition, leaching is a heterogeneous reaction dependent on the particle-size distribution in the feed and on the kinetics of particle shrinkage . In this study, these effects are incorporated in the material balance for each mineral by the number balance . Examination of the number balance gives rise to a novel analysis of the competing technologies for leaching . The model is completed by the addition of material balances for the ferrous and ferric ions, the dissolved oxygen, and for each bacterial species to the number balance for each mineral present in the feed . The model is compared with pilot plant data for three different ores . It is shown that the model is in excellent agreement with the data . The performance of a bacterial leaching reactor is explored using the model, and the washout and sensitivity criteria are determined . It is shown that there are three washout conditions, in which the leaching conversion drops to zero . The washout conditions are dependent on the growth rate of the bacteria, on the rate of dissolution of the mineral, and on the rate of mass transfer of oxygen to the reactor . The critical washout condition is that arising from the rate of mineral dissolution . The optimization of a plant in which continuous tank reactors are configured in series is addressed . This analysis shows that the primary reactor should be between 1.5 and 2 times the size of each of the secondary reactors in a series combination. J Immunol, 2001 Apr 15, 166(8), 5000 - 7 Bacterial CpG-DNA triggers activation and maturation of human CD11c-, CD123+ dendritic cells; Bauer M et al.; Human plasmacytoid precursor dendritic cells (ppDC) are a major source of type I IFN upon exposure to virus and bacteria, yet the stimulus causing their maturation into DCs is unknown . After PBMC activation with immunostimulatory bacterial DNA sequences (CpG-DNA) we found that ppDC are the primary source of IFN-alpha . In fact, either CpG-DNA or dsRNA (poly(I:C)) induced IFN-alpha from purified ppDC . Surprisingly, only CpG-DNA triggered purified ppDC survival, maturation, and production of TNF, GM-CSF, IL-6, and IL-8, but not IL-10 or IL-12 . Known DC activators such as CD40 ligation triggered ppDC maturation, but only IL-8 production, while bacterial LPS was negative for all activation criteria . An additional finding was that only CpG-DNA could counteract IL-4-induced apoptosis in ppDC . Therefore, CpG-DNA represents a pathogen-associated molecular pattern for ppDC . In contrast to these finding, CpG-DNA, like LPS, caused TNF, IL-6, and IL-12 release from PBMC and purified monocytes; however, differentiation of monocytes into DCs with GM-CSF and IL-4 unexpectedly resulted in refractoriness to CpG-DNA, but not LPS . Taken together, these results suggest that within a DC subset a multiplicity of responses can be generated by distinct environmental stimuli and that responses to a given stimulus may be dissimilar between DC subsets. Genetics, 2001 Apr, 157(4), 1749 - 57 High-resolution pachytene chromosome mapping of bacterial artificial chromosomes anchored by genetic markers reveals the centromere location and the distribution of genetic recombination along chromosome 10 of rice; Cheng Z et al.; Large-scale physical mapping has been a major challenge for plant geneticists due to the lack of techniques that are widely affordable and can be applied to different species . Here we present a physical map of rice chromosome 10 developed by fluorescence in situ hybridization (FISH) mapping of bacterial artificial chromosome (BAC) clones on meiotic pachytene chromosomes . This physical map is fully integrated with a genetic linkage map of rice chromosome 10 because each BAC clone is anchored by a genetically mapped restriction fragment length polymorphism marker . The pachytene chromosome-based FISH mapping shows a superior resolving power compared to the somatic metaphase chromosome-based methods . The telomere-centromere orientation of DNA clones separated by 40 kb can be resolved on early pachytene chromosomes . Genetic recombination is generally evenly distributed along rice chromosome 10 . However, the highly heterochromatic short arm shows a lower recombination frequency than the largely euchromatic long arm . Suppression of recombination was found in the centromeric region, but the affected region is far smaller than those reported in wheat and barley . Our FISH mapping effort also revealed the precise genetic position of the centromere on chromosome 10. Cell, 2001 Mar 23, 104(6), 901 - 12 Structural mechanism for rifampicin inhibition of bacterial rna polymerase; Campbell EA et al.; Rifampicin (Rif) is one of the most potent and broad spectrum antibiotics against bacterial pathogens and is a key component of anti-tuberculosis therapy, stemming from its inhibition of the bacterial RNA polymerase (RNAP) . We determined the crystal structure of Thermus aquaticus core RNAP complexed with Rif . The inhibitor binds in a pocket of the RNAP beta subunit deep within the DNA/RNA channel, but more than 12 A away from the active site . The structure, combined with biochemical results, explains the effects of Rif on RNAP function and indicates that the inhibitor acts by directly blocking the path of the elongating RNA when the transcript becomes 2 to 3 nt in length. J Biomed Mater Res, 2001 Jun 15, 55(4), 547 - 53 Synergistic induction of cyclooxygenase-II by bacterial lipopolysaccharide in combination with particles of medical device materials in a murine macrophage cell line J774A.1; Lee DH et al.; Corrosion and wear of implanted medical devices may produce particulate debris, leading to acute and chronic inflammatory responses in the host . In the presence of biomaterial wear particles, host monocytes/macrophages are activated to synthesize or secrete mediators of inflammation . In order to understand the mechanisms underlying the host response to particulates and device-associated infections, we have focused on the effects of medical device particles on macrophage function, because these cells play a pivotal role in the body's response to foreign bodies and their interaction with other cellular components of the immune system . In order to evaluate the effects of particles of medical device materials on functional activities of macrophages, we developed a cyclooxygenase-II (COX-II) assay system using J774A.1 macrophages . Constitutive cyclooxygenase (COX-I) is present in cells under physiological conditions, whereas inducible COX-II is induced by some cytokines, mitogens, and endotoxin, presumably in pathological conditions such as inflammation . We have evaluated the inductive effects of implant materials, i.e., particles of polymethylmethacrylate (PMMA), hydroxyapatite (HA), titanium oxide, and silica, on the activity of COX-II using thin layer chromatography of prostaglandin D(2) (PGD(2)) formed from {1-(14)C}-labeled arachidonic acid (AA) . Also, we have assessed the synergistic effects of these particles on lipopolysaccharide (LPS)-mediated macrophage activation . Addition of LPS to these particles increased PGD(2) production several-fold greater than the addition of any inducer alone . Our results indicated that device-associated infections could enhance inflammatory responses to the wear particles in subjects with medical implants or in whom particulate biomaterials are used for clinical purposes . The use of this model COX-II assay system may lead to the identification of inflammatory potentials for implant materials more specifically than present in vivo assays .
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