J Clin Microbiol, 1997 Apr, 35(4), 862 - 6 Improved detection of bacterial growth in continuous ambulatory peritoneal dialysis effluent by use of BacT/Alert FAN bottles; Alfa MJ et al.; Culture-negative peritonitis is a major complication for patients on continuous ambulatory peritoneal dialysis (CAPD) and precludes organism-specific therapy . The aim of the present study was to compare inoculation of 10 ml of CAPD effluent into BacT/Alert blood culture bottles (FAN {fastidious antimicrobic neutralizing}, BacTAlert aerobic {BTA}, and BacT/Alert anaerobic {BTAn} bottles) to our conventional method of using 50 ml of concentrated CAPD effluent to inoculate peptone broth bottles (BD bottles) and MacConkey agar and blood agar medium (BA-MAC) . The FAN, BTA, and BTAn bottles were monitored automatically in the BacT/Alert blood culture instrument . A total of 207 CAPD effluents were studied, and in 97 bacteria were detected by at least one method . Compared to BTA bottles (79 of 97; 81.4%), BTAn bottles (78 of 97; 80.4%), and BD bottles (88 of 97; 90.7%), the single best broth medium for detecting bacterial growth in CAPD effluents was the FAN bottle (90 of 97 effluents; 92.8%) . A total of 125 bacterial species were detected by any method, and the majority (91.8%) of CAPD effluents were infected with a single species . A combination of FAN and BTAn bottles detected 111 of 125 (88.8%) of all organisms, whereas a combination of BD bottles and BA-MAC detected 107 of 125 (85.6%) of all organisms . One or more organisms that would have been completely missed by the conventional method with BD bottles and BA-MAC were detected in 18 CAPD effluents . Of these 18 CAPD effluents, 6 showed no growth by the conventional method with BD bottles and BA-MAC . On the basis of our data, the most sensitive and least labor intensive method was direct inoculation of 10 ml of CAPD effluent into a FAN bottle and a BTAn bottle, which could be automatically monitored by the BacT/Alert blood culture instrument . On the basis of case definitions for peritonitis, the sensitivities and specificities of the methods with FAN and BTAn bottles and with BD bottles and BA-MAC were 81.1 and 98.8% and 74.5 and 96.5%, respectively. Crit Care Med, 1997 Apr, 25(4), 607 - 13 Cytokines, nitrite/nitrate, soluble tumor necrosis factor receptors, and procalcitonin concentrations: comparisons in patients with septic shock, cardiogenic shock, and bacterial pneumonia; de Werra I et al.; OBJECTIVES: To determine and compare the respective concentrations of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, soluble TNF receptors, nitrite/nitrate (NO2-/NO3-), and procalcitonin in the plasma of patients with septic shock, cardiogenic shock, and bacterial pneumonia without shock; and to assess the predictive value of these mediators in defining patients with septic shock . DESIGN: Cohort study, comparing normal volunteers (controls) and patients with septic shock, cardiogenic shock, and bacterial pneumonia . SETTING: A collaborative study among an intensive care unit, an emergency room, and three research laboratories . PATIENTS: Mediators were measured at various times in 15 patients with septic shock (during the shock phase and during the recovery phase), in seven patients with cardiogenic shock during the shock phase, and in seven patients with severe bacterial pneumonia on day 1 of admission . INTERVENTIONS: Blood samples were collected at various times during the course of the disease . MEASUREMENTS AND MAIN RESULTS: TNF-alpha values were highest in the acute phase of septic shock (53 to 131 pg/mL during septic shock), while patients with bacterial pneumonia had intermediate concentrations (32 pg/mL) . TNF-alpha concentrations were normal in patients with cardiogenic shock . IL-6 concentrations were highest in patients with acute septic shock (85 to 385 pg/mL) . However, in contrast to TNF-alpha concentrations, IL-6 concentrations were normal in patients with bacterial pneumonia and increased in patients with cardiogenic shock (78 pg/mL) . Soluble TNF receptors were increased in all three groups vs . controls, with the highest increase in patients with septic shock . NO2-/NO3- concentrations were highest (72 to 140 mM) in patients with septic shock, and were < 40 mM in the other groups of patients . Procalcitonin concentrations were only markedly increased in patients with septic shock (72 to 135 ng/mL, compared with approximately 1 ng/mL in the three other groups) . The best predictive value for septic shock was found to be the measurements of NO2-/NO3- and procalcitonin concentrations . CONCLUSIONS: These observations showed that increase of proinflammatory cytokines was a consequence of inflammation, not of shock . In this study comparing various shock and infectious states, measurements of NO2-/NO3- concentration and procalcitonin concentration represented the most suitable tests for defining patients with septic shock. J Nat Prod, 1997 Apr, 60(4), 397 - 8 Modulation of lipoxygenase activity by bacterial hopanoids; Moreau RA et al.; Tetrahydroxybacteriohopane (1), a bacterial hopanoid, inhibited soybean 15-lipoxygenase with an IC50 of about 10 microM . After per-O-acetylation of 1 no inhibition of the 15-lipoxygenase was observed . Two other bacterial hopanoids, tetrahydroxybacteriohopane glucosamine (2) and tetrahydroxybacteriohopane ether (3), stimulated the activity of soybean 15-lipoxygenase . The activities of two other arachidonic acid-metabolizing enzymes, human 5-lipoxygenase and prostaglandin H synthase, were unaffected by 1. Masui, 1997 Apr, 46(4), 552 - 5 {Importance of instructing anesthesiologists in handwashing against bacterial contamination}; Fukada T et al.; The importance of handwashing in preventing the spread of nosocomial infection has been stressed . Using a modified glove juice method, we have already shown the efficacy of washing of anesthesiologists' hands with alcohol based antiseptic solutions against bacterial contamination . The efficacy of handwashing, however, varied because many anesthesiologists washed only the palm and the back . In the present study, we instructed them to wash their hands using rubbing method, from finger tip to the wrist until drying the solutions completely . We compared the efficacy of handwashing, by decrease of bacteria counts after general anesthesia, between the instructed method and the customary way which was done ordinarily in the ward . The instructed method was more effective on the decrease of bacteria counts than the customary way . In the instructed method, the efficacy of handwashing was not different between the antiseptic solutions . In conclusion, doctors not only should practice handwashing with the antiseptic solutions after each contact with the patient, but also wash their hands from the finger tip to the wrist until they become completely dry. J Immunol, 1997 Apr 1, 158(7), 3457 - 62 Detection and biochemical characteristics of the receptor for complexes of soluble CD14 and bacterial lipopolysaccharide; Vita N et al.; Soluble CD14 (sCD14) has been found to bind LPS and mediate LPS activation of several cell types . It has been postulated that sCD14-LPS complexes induce cell responses by interacting with a cell surface structure, which, in turn, triggers cell activation . There has been no biochemical evidence, however, for a direct interaction of sCD14 with a cell surface structure, and the putative receptor has not been identified . To rigorously test this hypothesis, we studied the interaction of human rsCD14 with cells in the absence of serum and in the presence and the absence of LPS . We found 1) there was specific and saturable binding of 125I-sCD14, indicative of a typical receptor-ligand interaction, to several cell types, including endothelial cells, epithelial cells, astrocytes, and human monocytes; 2) specific binding to all the cell types and IL-6 induction in membrane-bound CD14 (mCD14)-negative cells occurred only when both sCD14 and LPS were present; 3) competitive displacement experiments of 125I-sCD14 binding to astrocytes and Scatchard plots revealed a binding of high affinity (Kd = 3.3 +/- 0.4 nM) and approximately 25,000 single class binding sites/cell; 4) the steady state for the association of 125I-sCD14 was obtained after 180-200 min; 5) chemical cross-linking experiments revealed the association of sCD14 with a binding structure of approximately 216 kDa; 6) binding of 125I-sCD14 to CD14-expressing cell transfectants was about 50% lower than that to nontransfected cells . Maximal binding, however, was recovered after removing mCD14, suggesting that the sCD14-LPS receptor may also interact with mCD14 . These results provide direct biochemical evidence for the existence of a cell surface signal-mediating binding structure for LPS-bearing sCD14 and suggest that this structure may represent the signaling unit of the postulated multimeric LPS receptor in mCD14-bearing cells. J Neuroimmunol, 1997 Apr, 74(1-2), 130 - 4 Endothelial-derived adhesion molecules in bacterial meningitis: association to cytokine release and intrathecal leukocyte-recruitment; Fassbender K et al.; The release of circulating isoforms of selectin- (L-selectin, ELAM-1) and immunoglobulin-type- (ICAM-1) adhesion molecules, responsible for accumulation of leukocytes at sites of tissue injury was studied in CSF and serum of 21 patients with bacterial meningitis and in healthy subjects . Their concentrations were compared with the intrathecal leukocyte recruitment and release of inflammatory cytokines . In contrast to serum concentrations of the leukocyte-derived adhesion molecule, sL-selectin, serum concentrations of endothelial-derived adhesion molecules, sELAM-1 and sICAM-1, were significantly increased in meningitis . No intrathecal synthesis of these adhesion molecules was observed . Serum levels of sELAM-1 were associated with extent of CSF pleocytosis and with concentrations of proinflammatory cytokines IL-1beta and TNF alpha in CSF, but not in serum . Therefore, expression of endothelial adhesion molecules i.e . ELAM-1 may be responsible for the massive intrathecal recruitment of potentially harmful leukocytes in patients with bacterial meningitis . Intrathecally released proinflammatory cytokines may represent the inducing signals for their endothelial upregulation. Genome Res, 1997 Apr, 7(4), 330 - 8 Analysis of the 1.1-Mb human alpha/delta T-cell receptor locus with bacterial artificial chromosome clones; Boysen C et al.; Bacterial artificial chromosome (BAC) clones are effective mapping and sequencing reagents . The 1.1-Mb alpha/delta T-cell receptor locus of humans was mapped and partially sequenced with BAC clones . Seventeen BAC clones covered the 1.1-Mb alpha/delta locus, with the exception of one small gap that was expected from the coverage that a 3.7-fold BAC library is likely to provide . The end sequences of the BAC inserts could be obtained directly from the BAC DNA by sequencing with the chain terminator chemistry . Five complete BAC inserts were sequenced directly by the shotgun approach . The ends of the 17 BAC inserts were distributed evenly across the locus . By several independent criteria, the BAC clones faithfully represented the genomic DNA, with the exception of a single clone with a 68-kb deletion . These BAC features led to the proposal of a new approach to sequence the human genome. Dermatol Clin, 1997 Apr, 15(2), 341 - 9 Current aspects of bacterial infections of the skin; Sadick NS; The practicing dermatologist is faced with an ever-changing epidemiologic spectrum of cutaneous bacterial diseases . Studies have stated that bacterial skin infections may account for up to 17% of clinical visits . It is hoped that the information presented in this article will enable the practicing dermatologist to provide improved patient care in the diagnosis and management of bacterial infections of the skin. Clin Exp Immunol, 1997 Apr, 108(1), 19 - 25 Detection of T cells reactive to intestinal alkaline phosphatase, an autoantigen in acute bacterial infections, and discrimination between autoantigen-specific CD5+ and CD5- B cells; Kolbus N et al.; Autoantibodies of the IgG isotype, specifically directed against intestinal alkaline phosphatase (IAP), occur transiently in the majority of sera from patients with acute bacterial infections . Sometimes they are observed in autoimmune diseases . Using a T cell proliferation assay, it was found that isolated peripheral blood mononuclear cells (PBMC) from IAP autoantibody (IAPA)-positive patients (n = 18) responded significantly to IAP, whereas proliferation could not be induced in PBMC from healthy donors (n = 11) . Significant stimulation of PBMC from patients (n = 11) was not obtained by use of transferrin, a common autoantigen in humans, indicating the specificity of stimulation of IAP-reactive T cells . Furthermore, T cell proliferation was observed when a highly purified IAP fragment (CNBr 21) spanning amino acids 334-462 of the primary structure of IAP was used as antigen . Thus, it was shown that an immunodominant T cell epitope resides within the CNBr 21 fragment which also contains a discontinuous B cell epitope as evaluated previously . Double immunocytochemical staining of T cell-depleted PBMC with IAP and an anti-human CD5 antibody allowed the detection of CD5+ B lymphocytes, which probably produce natural IAPA (nIAPA) . These nIAPA-specific CD5+ B cells occurred with approximately the same frequency among T cell-depleted PBMC from healthy donors and those from patients . In contrast, IAPA-producing CD5- B cells were found in B cell-enriched preparations from patients, but not in those from healthy individuals. RNA, 1997 Apr, 3(4), 420 - 8 Unconventional structure of tRNA(Lys)SUU anticodon explains tRNA's role in bacterial and mammalian ribosomal frameshifting and primer selection by HIV-1; Agris PF et al.; Transfer RNA(Lys)SUU, with a 5-modified-2-thiouridine at wobble position 34, facilitates -1 frameshifts for correct translation of the Escherichia coli DNA polymerase gamma subunit and retroviral polymerases . Peptidyl-tRNA(Lys)SUU prematurely terminates translation more often than other tRNAs . In order to determine if the anticodon structures of bacterial and mammalian tRNA(Lys)SUU species explain these observations, oligonucleotides corresponding to the anticodon regions of mammalian and E . coli tRNA(Lys)SUU were synthesized and their physicochemical properties compared with that of E . coli tRNA(Glu)SUC . The anticodon region of tRNA(Lys)SUU was stabilized by an unusual interaction between the side chains of the 5-modified-s(2)U34 and N-6-threonylcarbamoyl-adenosine-37 (t(6)A37), a combination of modified nucleosides unique to tRNA(Lys)SUU species . This first observation of modified nucleoside side-chain interactions is analogous to the interactions of amino acid side chains in proteins . The tRNA(Lys)SUU anticodon structure was determined from NMR restraints on model oligonucleotides . With only two of three anticodon bases available for codon pairing, this unconventional anticodon structure is a reasonable explanation for the bacterial and mammalian tRNA(Lys)SUU tendency to frameshift . A two-out-of-three reading of coding triplets also explains the increased rate at which peptidyl-tRNA(Lys)SUU prematurely terminates translation . In addition, modified nucleoside interaction distorts the anticodon loop . The distorted loop is a possible structural determinant for the preferential selection of tRNA(Lys3)SUU as primer of HIV-1 reverse transcriptase in vivo. J Bacteriol, 1997 Apr, 179(7), 2228 - 37 The bacterial nucleoid visualized by fluorescence microscopy of cells lysed within agarose: comparison of Escherichia coli and spirochetes of the genus Borrelia; Hinnebusch BJ et al.; The nucleoids of Escherichia coli and the spirochetes Borrelia burgdorferi and Borrelia hermsii, agents of Lyme disease and relapsing fever, were examined by epifluorescence microscopy of bacterial cells embedded in agarose and lysed in situ with detergent and protease . The typical E . coli nucleoid was a rosette in which 20 to 50 long loops of DNA emanated from a dense node of DNA . The percentages of cells in a population having nucleoids with zero, one, two, and three nodes varied with growth rate and growth phase . The borrelia nucleoid, in contrast, was a loose network of DNA strands devoid of nodes . This nucleoid structure difference correlates with the unusual genome of Borrelia species, which consists primarily of linear replicons, including a 950-kb linear chromosome and linear plasmids . This method provides a simple, direct means to analyze the structure of the bacterial nucleoid. Biochem Biophys Res Commun, 1997 Mar 27, 232(3), 806 - 9 A 65-kilodalton nuclear protein binds to the human vitamin D receptor: a bacterial-expressed histidine-tagged receptor study; Nakajima S et al.; We report here that the human 1,25-dihydroxyvitamin D3 receptor (hVDR) binds to a 65 kD nuclear protein in a ligand-dependent manner . Histidine-tagged full-length hVDR was overexpressed in E.coli and purified to near homogeneity using Ni-NTA and gel filtration columns without denature/renature procedures . Nuclear extract from the osteoblastic cell line MG-63 was incubated with the recombinant hVDR and Ni-NTA agar in the presence of a double-stranded DNA fragment containing vitamin D responsive element . Proteins bound to the hVDR were eluted and analyzed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis . A 65 kD protein was detected with full-length hVDR in the presence of 100 nM 1,25(OH)2D3, while this interaction was not observed in the absence of the ligand nor with carboxyl-terminally truncated hVDR, which lacks an activation function-2 domain . Therefore, this nuclear protein may be involved in the ligand-dependent transcriptional regulation via the hVDR. Biochem Biophys Res Commun, 1997 Mar 27, 232(3), 707 - 11 Cytotoxicity resulting from addition of HIV-1 Nef N-terminal peptides to yeast and bacterial cells; Macreadie IG et al.; The Nef protein of human immunodeficiency type 1 (HIV-1) has been implicated in diverse intracellular functions; however, extracellular functions have been less studied . Nef and the N-terminus of Nef possess membrane-perturbing and fusogenic activities in artificial membranes that also cause cytotoxicity to human cells, including lymphocytes . The present study investigates the toxicity of HIV-1 Nef peptides employing yeast and bacterial cells . The N-terminal portion of Nef was found to cause cell killing in Escherichia coli and in a variety of yeast cells . This activity was enhanced by myristylation of the Nef N-terminus, a modification that did not lead to toxicity in a control peptide . Cell death in yeast was due to permeabilization of the cell membrane as determined by the propidium iodide uptake of peptide-treated cells . Extracellular Nef, or its breakdown products, may have effects similar to the Nef peptides described here and could be responsible, at least in part, for the death of cells in lymphoid tissues during AIDS . Assays using yeast or bacteria are convenient, inexpensive, and robust and should be useful in further analysis and screening of inhibitors of this activity associated with HIV-1 Nef. J Biol Chem, 1997 Mar 21, 272(12), 7582 - 5 Bacterial lipopolysaccharide plus interferon-gamma elicit a very fast inhibition of a Ca2+-dependent nitric-oxide synthase activity in human astrocytoma cells; Colasanti M et al.; Previous results indicate that induction of inducible nitric-oxide synthase (iNOS) expression may be kept suppressed by the endogenous NO level as produced by a constitutive NOS (cNOS) enzyme . In cell types possessing both cNOS and iNOS, this may represent an evident paradox . Here, we report that lipopolysaccharide and interferon-gamma, which are able to strongly induce iNOS in astrocytoma cells, can rapidly inhibit the NO production generated by the constitutive NOS isoform, thus obtaining the best conditions for iNOS induction and resolving the apparent paradox . In fact, a 30-min treatment of T67 cells with the combination of lipopolysaccharide plus interferon-gamma (MIX) strongly inhibits the cNOS activity, as determined by measuring {3H}citrulline production . In addition, the effect of MIX is also observed by measuring nitrite, the stable breakdown product of NO: a 30-min pretreatment of T67 cells with MIX is able to reduce significantly the N-methyl-D-aspartate-induced nitrite production . Finally, using reverse transcriptase-polymerase chain reaction, we have observed that a 30-min treatment of T67 cells with MIX does not affect expression of mRNA coding for the neuronal NOS-I isoform . These results suggest the novel concept of a possible role of a cNOS isoform in astrocytes as a control function on iNOS induction. Biochem Biophys Res Commun, 1997 Mar 17, 232(2), 364 - 6 A fatty acid alpha-ketol, a product of the plant lipoxygenase pathway, is oxidized to 3(Z)-dodecendioic acid by a bacterial monooxygenase; Schneider C et al.; The fatty acid alpha-ketol 13-hydroxy-12-oxo-9(Z)-octadecenoic acid (methyl ester) was incubated with a bacterial culture isolated from soil . The bacteria (tentatively identified as Ralstonia sp.) exhibited strong monooxygenase activity growing on 2-tridecanone as sole source of carbon . They catalyzed a Baeyer-Villiger type of oxidation and converted the alpha-ketol to 3(Z)-dodecendioic acid . 3(Z)-Dodecendioic acid was isolated from the incubation mixture and identified by comparison with an authentic reference compound . These findings offer both a physiological role for alpha-ketol fatty acids in plant lipid hydroperoxide metabolism and new insights into an alternative biosynthetic pathway leading to traumatic acid (2(E)-dodecendioic acid). Mutat Res, 1997 Mar 17, 389(2-3), 183 - 90 Genotoxicity of platinum and palladium compounds in human and bacterial cells; Gebel T et al.; Platinum and palladium belong to the group of platinum elements and thus share many chemical properties . Platinum coordination complexes are known to be carcinogenic and genotoxic in mammalian and bacterial cells . However, little is known about palladium genotoxicity . This study compares and evaluates the genotoxic potential of selected platinum and palladium metal salts in mammalian and bacterial cells using the cytokinesis-block micronucleus test (MNT) with human lymphocytes and the bacterial SOS chromotest . Carboplatin, cisplatin(II), transplantin(II), PtCl4(IV), and K2PtCl4(II) caused a significantly elevated genotoxicity in the MNT and the SOS chromotest . The platinum compounds PtCl2(II) and K2PtCl6(IV), and the divalent palladium salts PdCl2(II), K2PdCl4(II), Pd(NH3)2J2(II), Pd(NH3)4Cl2(II), and transpalladium(II) were not genotoxic in the MNT nor in the SOS chromotest . Therefore, evidence for palladium genotoxicity seems to be low in mammalian and bacterial cells. Eur J Biochem, 1997 Mar 15, 244(3), 767 - 73 Role of Escherichia coli histone-like nucleoid-structuring protein in bacterial metabolism and stress response--identification of targets by two-dimensional electrophoresis; Laurent-Winter C et al.; The histone-like nucleoid-structuring protein, H-NS, is a major bacterial chromatin component which influences DNA structure and gene expression . Mutations in hns, the structural gene of H-NS protein, have been shown to result in highly pleiotropic effects in Escherichia coli cells . In this study, we have initiated an index of the proteins whose synthesis is, directly or indirectly regulated by H-NS . Using two-dimensional gel electrophoresis, we have examined the global changes in gene expression which occured in an hns background compared with its wild-type parent . In addition, we analysed the effects of mutations in two other genes i.e . lrp and pta, which are also involved in global regulatory pathways . Although these comparative analyses revealed several common differences, thus suggesting possible interactions between these regulatory mechanisms, i.e . H-NS, Lrp (leucine-responsive regulatory protein) and acetylphosphate, the most extensive modifications occurred in an hns mutant . Among the polypeptides whose level of synthesis was specifically altered in an hns mutant, several corresponded to H-NS targets previously identified by classical selection methods . Moreover, the present study allows us to characterize several H-NS targets, which were identified either by comparison with the E . coli two-dimensional reference maps or by microsequencing procedure . Many of these newly identified polypeptides are involved in adaptation of E . coli cells to environmental challenges, and one of them could be involved in bacterial virulence . Finally, synthesis of several proteins belonging to the heat-shock regulon, more particularly molecular chaperones, was induced in an hns mutant. Cell Immunol, 1997 Mar 15, 176(2), 127 - 34 Bacterial cell wall products increase monocyte HLA-DR and ICAM-1 without affecting lymphocyte CD18 expression; Heinzelmann M et al.; Bacterial cell wall products such as lipopolysaccharide (LPS) and muramyl dipeptide (MDP) have the capacity to enhance immune responses to antigens . The expression of surface class II major histocompatibility antigens and the costimulatory receptors CD18 and CD54/ICAM-1 (intercellular adhesion molecule) was used to evaluate the comparative influence of these immunostimulators . On monocytes, both LPS and MDP increased the expression of human leukocyte antigen (HLA)-DR (maximal at 6 hr), CD18 (maximal at 1-3 hr), and ICAM-1 (maximal at 18-24 hr for LPS and 12 hr for MDP) without increasing the production of superoxide . MDP-induced ICAM-1 expression on monocytes returned to baseline values after 12 hr . On lymphocytes, only LPS increased ICAM-1 (after 18 hr) without affecting CD18, and a differential analysis demonstrated a generalized ICAM-1 upregulation in lymphocyte subsets after 18 hr: the most pronounced effect was measured in natural killer cells, followed by CD8(+) T cells, B cells, and CD4(+) T cells . MDP did not alter ICAM-1 or CD18 expression on lymphocytes . These similar but smaller effects of MDP may, in part, explain the lesser toxicity of MDP when compared to LPS. Presse Med, 1997 Mar 8, 26(7), 340 - 3 {Prevention of opportunistic infections in HIV seropositive patients . Prevention of bacterial infections}; Casassus P et al.; TUBERCULOSIS: Primary prophylaxis is indicated in subjects at risks, i.e . those with a positive tuberculine test or a negative test and major immunodepression . BCG vaccine is definitely contraindicated in case of AIDS . Prescription of isoniazid in combination with vitamin B6 has been found to be effective . MYCOBACTERIUM AVIUM INTRACELLULARE: Prophylaxis concerns highly immunodepressed patients and is based on rifabutine . Prophylaxis is contraindicated in case of active tuberculosis . OTHER GERMS: Preventive care in food intake for potential digestive tract infections is required as well as antipneumococcal vaccine . Secondary prophylaxis is based on continuous antibiotics . The positive effect of intravenous immunoglobulins, especially in children, remains a question of debate. Zh Mikrobiol Epidemiol Immunobiol, 1997 Mar-Apr, (2), 47 - 50 {The expression of Bordetella pertussis protective antigens during bacterial multiplication on a medium with a fixed chemical composition}; Shmeleva EI et al.; The possibility of obtaining native pertussis preparations with high immunobiological activity has been shown . To obtain such preparations, the use of B . pertussis selected strain, its growth under the conditions of static cultivation in a synthetic culture medium and the use of supernatants with the maximum content of protective antigens with the aim of obtaining protective complexes are necessary. Mikrobiologiia, 1997 Mar-Apr, 66(2), 223 - 7 {Regulated expression of bacterial luminescence genes cloned in a multicopy recombinant plasmid}; Maksimova EE et al.; Luminescence and growth responses of the recombinant strain Escherichia coli Z905 (AprLux+) to different concentrations of ampicillin depended on the source of carbon and energy . When glycerol was used as the substrate, the intensity of luminescence rose with the ampicillin concentration in the medium . Glucose caused catabolite repression of cell luminescence up to the late stationary phase, and ampicillin enhanced this effect . The feasibility of controlling the expression of cloned lux genes was shown. Hepatogastroenterology, 1997 Mar-Apr, 44(14), 411 - 6 The effect of granulocyte colony-stimulating factor (G-CSF) on bacterial translocation in the splenectomized rat; Paksoy M et al.; BACKGROUND/AIMS: We created a study group in order to investigate the effects of splenectomy and filgrastim . Filgrastim is an immunomodulator granulocyte colony-stimulating factor (G-CSF), that affects bacterial translocation . MATERIALS AND METHODS: We created 3 study groups with 30 male Sprague-Dawley rats; the first group included sham splenectomy, the second group was splenectomy, and the third group was splenectomy+ filgrastim group . RESULTS: The mean bacterial colony count of the cecum were 2.5 x 10(9) in group 1, 1.2 x 10(10) in group 2 and 3.5 x 10(9) in group 3 . The differences between these groups were accepted as statistically significant . The mean counts of the terminal ileum were 1.1 x 10(9) in group 1, 5.5 x 10(10) in group 2 and 2.5 x 10(10) in group 3 . The p values of group 1-2 were 0.036 (statistically significant) and 0.123 in groups 2-3) were not statistically significant . The mean counts of the liver were 0.2 x 10(4), 1 x 10(10) and 3.4 x 10(5), respectively . In comparison of the groups the p values of the first and last 2 groups were found to be 0.047 (statistically significant) . The mean counts of the mesenteric lymph node were 0.7 x 10(3), 1 x 10(10) and 0.9 x 10(6) respectively . The p values were 0.343 for the first and the last 2 groups both . As they were above 0.05, they were not statistically significant . The degrees of liver Kupffer cell hyperplasia were (+) 40%, (+2) 50% and (+3) 10% (group 1), (+) 10%, (+2) 40% and (+3) 50% (group 2), (+2) 60% and (+3) 40% (group 3) (p = 0.0039) . The rates of the absence of pathology in mesenteric lymph nodes were 70% (group 1), 90% (group 2) and 100% (group 3) (p = 0.049) . These findings were statistically significant . CONCLUSIONS: We found that splenectomy has activated the whole predisposing factors of bacterial translocation and created the latter itself . In addition, we showed that filgrastim, a recently widespread used G-CSF, decreases bacterial translocation significantly. J Laryngol Otol, 1997 Mar, 111(3), 223 - 7 Evaluation of hearing loss with auditory brainstem responses in the early and late period of bacterial meningitis in children; Kulahli I et al.; The hearing function of 50 children with bacterial meningitis was evaluated at the second and 10th days, and eight weeks after admission with auditory brain system responses (ABR) to investigate whether meningitis causes hearing loss . Normal values were obtained in all tests from both ears of 24 patients (48 per cent) . Twelve patients (24 per cent) had temporary, and seven (14 per cent) patients had persistent mild degree hearing loss . Severe hearing loss was detected bilaterally in five (10 per cent) patients and unilaterally in two (four per cent) patients . Patients, with other complications such as subdural effusion, convulsion, brain oedema and paralysis were found to have a higher incidence of hearing loss . We observed that patients treated with dexamethasone had 7.7 per cent persistent hearing loss, 11.6 per cent mild hearing loss, 34.6 per cent transient hearing loss, but in the group who did not receive dexamethasone there was 19.2 per cent persistent hearing loss, 15.3 per cent mild hearing loss and 11.6 per cent transient hearing loss . There were other significant differences between the two groups in restoration of normal body temperature, the CSF/plasma glucose concentration ratio was elevated, CSF (cerebro-spinal fluid) protein concentration was decreased and the cell count in the CSF was decreased in the dexamethasone group, significantly more than the group who were not receiving dexamethasone . The hearing loss tended to be more frequent among younger children. J Pathol, 1997 Mar, 181(3), 338 - 46 Hypercoagulable state in a hypobaric, hypoxic environment causes non-bacterial thrombotic endocarditis in rats; Nakanishi K et al.; High-altitude hypoxia causes polycythaemia and a hypercoagulable state in humans and animals . This study examines the effects of a hypobaric, hypoxic environment (HHE) on the blood coagulation system in rats . A total of 170 male Wistar rats were housed in a chamber at the equivalent of 5500 m in altitude for 1-12 weeks . After 2 weeks of exposure to HHE, platelet counts decreased significantly; after 4 weeks, the prothrombin and activated partial thromboplastin times were significantly prolonged, compared with those of control rats . In addition, individual coagulation factors (VII, IX, X, XI, and XII) were significantly decreased at 8 weeks (P < 0.05) . Levels of anti-thrombin III and alpha 2-plasmin inhibitor also decreased (between 4 and 8 weeks) . After 4-12 weeks of exposure to HHE, 30 of 56 rats (54 per cent) developed (i) non-bacterial thrombotic endocarditis (NBTE) or (ii) infarction of the myocardium or kidney, or both (i) and (ii) . The incidence of NBTE increased from 33 per cent (5/15 rats) at 4 weeks to 100 per cent (7/7 rats) at 12 weeks . Electron microscopy showed detached endothelial cells in the mitral valves at 1 week; platelets adhered to the subendocardial matrix and platelet aggregation with thrombus formation was seen at 2 weeks of exposure . The results suggest that exposure to HHE induces a hypercoagulable state and causes an NBTE in rats that may result in consumption coagulopathy. Clin Lab Med, 1997 Mar, 17(1), 129 - 45 Simultaneous multianalyte nucleic acid detection for gastrointestinal bacterial pathogens using GeneSTAR technology; Wu L et al.; The use of Gene-based simultaneous target amplification and recognition (GeneSTAR) technologies allows for the rapid detection of five different bacterial gastrointestinal pathogens from stool sample . The process involves DNA isolation, multianalyte polymerase chain reaction (PCR) amplification and single base mismatch detection in a microtiter plate format . The analysis is instrument compatible and can be completed in less than five hours. Anticancer Res, 1997 Mar-Apr, 17(2B), 1391 - 7 Disappearance of Ewing's sarcoma following bacterial infection: a case report; Mori Y et al.; We report a patient with multiple metastases of Ewing's sarcoma in whom the tumor vanished after a bacterial infection . To the best of our knowledge, no comparable case with Ewing's sarcoma has been reported in the literature . The patient was a 17-year-old male who had an irregular destructive lesion of the left pelvis on radiologic examination . Pathologic examination of a biopsy specimen revealed Ewing's sarcoma . After the operation, a roentgenogram showed multiple spinal metastases with paraplegia . Despite initiation of chemotherapy, a subsequent bone scan showed several areas of increased uptake indicating multiple metastatic lesions . A fistula with purulent discharge opened at the operative site . While being treated with antibiotics and fistula irrigation, the fistula narrowed and his high fever subsided . During this period, radiologic examinations indicated that the multiple bone metastases had nearly disappeared . Nine years after the operation, the patient is alive without any evidence of tumor . We postulate that the antitumor activity in this patient resulted from the bacterial infection, and believe that this case supports continued consideration of immunotherapy for cancer. J Int Neuropsychol Soc, 1997 Mar, 3(2), 147 - 58 Childhood bacterial meningitis: impact of age at illness and acute medical complications on long term outcome; Anderson V et al.; This study compared postmeningitic children (N = 130) with grade and sex matched controls (N = 130) selected from target children's schools on measures of intellectual, linguistic, learning, and reading skills . Results showed that children with a history of meningitis are at greater risk for impairment in these areas, with experience of the disease prior to 12 months of age being an important risk factor . Within the postmeningitic sample presence of medical complications was associated with poorer verbal abilities . Finally, a significant relationship was identified between depressed language skills and later educational difficulty, with these findings interpreted with respect to both developmental and neuropsychological principles. Ecotoxicol Environ Saf, 1997 Mar, 36(2), 133 - 9 Development and testing of an assay for soil ecosystem health using the bacterial-feeding nematode Cruznema tripartitum; Lau SS et al.; Survival and respiration rates of the bacterial-feeding nematode Cruznema tripartitum after incubation in soil for 48 hr provided a useful bioassay of the presence and concentration level of biologically active toxicants . The assay provided an indication of toxicant activity at sublethal levels, and a means of determining when the toxicant had declined to levels not deleterious to physiological function . Assays of soil contaminants based on the community structure of resident soil nematodes were more useful in undisturbed soils than in agricultural soils where the range of taxa was relatively narrow . Assays involving measurement of survival and respiration rates of nematodes after immersion in an aqueous extract of contaminated soils were not useful due to degradation and loss of contaminant during the extraction process. Zentralbl Veterinarmed A, 1997 Mar, 44(1), 55 - 63 Evaluation of hematological, serum biochemical and cerebrospinal fluid parameters in experimental bacterial meningitis in the calf; Nazifi S et al.; To evaluate the effects of bacterial meningitis on blood and CSF parameters, an experiment was conducted with five Iranian crossbred male calves . Blood and CSF samples were collected 3 times within a 5-day interval before the administration of bacteria for obtaining control values . Following the injection of E . coli, K12 into the cerebrospinal fluid from the lumbosacral space, samples were collected and clinical signs of meningitis were observed . Blood and CSF samples were obtained from the meningitis group 3 times at 1, 3, and 5 days post injection . The treatment of the infected calves using lincospectin and tetracycline was carried out immediately after the onset of clinical signs . After the treatment, blood and CSF samples were obtained 3 times during a 5-day period . Following the induction of meningitis, the number of WBCs, neutrophils, eosinophils and monocytes significantly increased (P < 0.05) . However, the percent of lymphocytes decreased significantly (P < 0.05) . The concentrations of glucose, potassium and activity of AST, LDH, CK significantly increased (P < 0.05) . In contrast, the concentrations of phosphorous, sodium and magnesium significantly decreased (P < 0.05) . Furthermore, following the induction of meningitis, the CSF was slightly xantochromic and turbid . The concentrations of protein, cholesterol, phosphorous, potassium, the activities of AST, LDH, CK, and the cell numbers in the CSF increased significantly (P < 0.05) . In contrast, the concentration of glucose and pH in the CSF decreased significantly (P < 0.05) . This study showed that bacterial meningitis can have profound effects on blood and CSF parameters which enable one to reach diagnosis. Scand J Immunol, 1997 Mar, 45(3), 294 - 300 Progressive accumulation of bacterial lipopolysaccharide in vivo during murine acute graft-versus-host disease; Price KS et al.; In a previous report the authors demonstrated that acute graft-versus-host disease (GVHD) was associated with pathologic amounts of tumour necrosis factor alpha (TNF-alpha) and the appearance of lipopolysaccharide (LPS) in the blood of GVH reactive mice just prior to death . In this study the authors have investigated the kinetics of LPS accumulation in different organs during the course of acute GVHD using a murine model . Unirradiated C57BL/6 x AF1 (B6AF(1)) mice were transplanted with C57BL/6 (B6) lymphoid cells and killed at predetermined times after transplantation for LPS analysis . Control animals were injected with either 60 x 10(6) B6AF1 lymphoid cells (syngeneic) or 60 x 10(6) irradiated (2000 rad) CBA lymphoid cells (allogeneic) . Lipopolysaccharide began to appear in the liver and the spleen of GVH reactive mice from day 2 post-transplant and by day 10 all GVH reactive mice tested positive for hepatic and splenic LPS . Low levels of LPS were detected in some control mice from days 2 to 10 post-transplant but LPS was never detected after day 10 in control groups . Total hepatic and splenic LPS in acute GVH reactive mice peaked at a time coincident with the appearance of LPS in the serum and with the onset of mortality . These results demonstrate that tissue levels of LPS increase throughout the course of acute GVHD and are sufficient to trigger the release of pathologic amounts of TNF-alpha from primed macrophages resulting in the cachexia and mortality associated with acute GVHD in this model. Chest, 1997 Mar, 111(3), 595 - 600 Laboratory abnormalities in patients with bacterial pneumonia; Sankaran RT et al.; STUDY OBJECTIVES: This study was undertaken to evaluate the laboratory abnormalities observed in patients with bacterial pneumonia as predictors of the severity of illness . DESIGN: Retrospective analysis . SETTING: Tertiary care hospital . PATIENTS AND PARTICIPANTS: We studied 302 consecutive patients who were admitted to the Long Island Jewish Medical Center from January through December 1993 and treated for bacterial pneumonia . The patients were subdivided into two groups based on their serum phosphorus level either on hospital admission or 4 days before the onset of pneumonia, if this was acquired in-hospital . Hypophosphatemia (group 1) was defined as serum phosphorus level of < or = 2.4 mg/dL and normophosphatemia > 2.4 mg/dL (group 2) . Three hundred randomly selected hospitalized patients treated for conditions other than pneumonia comprised the control group (group 3) . MEASUREMENTS: Groups 1 and 2 were compared with respect to laboratory data, mortality rate, and duration of hospitalization . The laboratory data of patients in group 3 were compared with those treated for bacterial pneumonia (groups 1 and 2) . Stepwise multivariate logistic regression analysis was employed to identify the variables that best predicted the onset of pneumonia . RESULTS: In groups 1 and 2, a greater (p < 0.0001) number of patients (135 of 302 patients with pneumonia, 44.7%) developed hypophosphatemia compared with patients in group 3 (31 of 300 control subjects, 10.3%) . Patients with pneumonia (groups 1 and 2) had higher levels (p < 0.01) of bicarbonate compared with control subjects . Moreover, patients with pneumonia demonstrated lower levels (p < 0.01) of calcium, phosphorus, albumin, cholesterol, and alanine aminotransferase compared with control patients (group 3) . Among patients with pneumonia, those with hypophosphatemia (group 1) had significantly lower levels (p < 0.05) of potassium, calcium, and albumin compared to those subjects with normophosphatemia (group 2) . Furthermore, hypophosphatemic subjects manifested higher levels of glucose (p < 0.01) and creatine phosphokinase (p < 0.05) compared to their normophosphatemic counterparts . In addition, hypophosphatemic patients experienced a longer duration of hospital stay (hypophosphatemia, 24.6 +/- 2.0 days, vs normophosphatemia, 14.1 +/- 1.0, p < 0.001) and higher (p < 0.001) mortality compared to normophosphatemic subjects . The incidence of nosocomial pneumonia was higher (p < 0.0001) in hypophosphatemic patients compared to those with normophosphatemia . CONCLUSION: We conclude that hypophosphatemia, hypocalcemia, hypokalemia, and hypoalbuminemia may be predictors of the severity of illness in patients admitted to the hospital with bacterial pneumonia. Antonie Van Leeuwenhoek, 1997 Mar, 71(3), 271 - 6 Bacterial evolution and silicon; Trevors JT; This review examines the possible role of silicon in molecular evolution . It is possible silicon participated in early molecular evolution by providing a stable mineral surface or gel structure where the assembly and replication of primitive genetic information occurred . However, as molecular evolution proceeded, silicon was not required in the evolution of C-based organisms . Silicon can be accumulated by diatoms and other living organisms such as silicoflagellates, some xanthophytes, radiolarians and actinopods and plants such as grasses, ferns, horseradish, some trees and flowers, some sponges, insects and invertebrates and bacteria and fungi . Silicon also has a role in synthesis of DNA, DNA polymerase and thymidylate kinase activity in diatoms . It is not unreasonable to examine the role of silicon in early molecular evolution as it may have been part of a micro-environment in which assembly of genetic information occurred. Antonie Van Leeuwenhoek, 1997 Mar, 71(3), 265 - 70 Evolution of bacterial genomes; Trevors JT; This review examines evolution of bacterial genomes with an emphasis on RNA based life, the transition to functional DNA and small evolving genomes (possible plasmids) that led to larger, functional bacterial genomes. J Soc Gynecol Investig, 1997 Mar-Apr, 4(2), 90 - 4 Characterization of the inflammatory cytokines in the vagina during pregnancy and labor and with bacterial vaginosis; Imseis HM et al.; OBJECTIVES: 1) To characterize the presence of interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) in the vagina during pregnancy and in labor; 2) to compare the vaginal levels of these inflammatory cytokines between laboring and nonlaboring patients; and 3) to compare the vaginal levels of these cytokines between women with and without bacterial vaginosis (BV) . METHODS: Vaginal fluid was obtained by lavage from pregnant women with intact membranes at various gestational ages and during labor at term . These samples were analyzed for specific cytokine levels using standard enzyme-linked immunosorbent assay techniques . A Gram stain, wet mount, and pH were obtained from the vaginal fluid and were used to diagnose BV . The Mann-Whitney U test was used to evaluate the individual cytokine levels between groups, with P < .05 considered statistically significant . RESULTS: There was a wide range of vaginal cytokine levels found in our pregnant population (N = 72) . Vaginal levels of IL-1 beta (median 1070 versus 245.7 pg/mL) and IL-6 (9.0 versus 0 pg/mL) were found to be significantly elevated in laboring patients as compared with nonlaboring patients (P = .005 and P = .002, respectively) . There were no significant differences in the levels of IL-1 alpha and TNF-alpha between the laboring and nonlaboring women . Interleukin-1 beta was also found to be significantly elevated in the group of patients with BV (3364 versus 245.7 pg/mL; P = .01), particularly those who were nonlaboring (P = .003) . In each individual patient, there was a wide variation in the levels of the four different cytokines . CONCLUSIONS: Measurable levels of the inflammatory cytokines IL-1 alpha, IL-1 beta, IL-6, and TNF-alpha were present in the vagina during pregnancy and labor . Vaginal levels of IL-1 beta and IL-6 were found to be significantly elevated in laboring patients as compared with nonlaboring patients . Vaginal levels of IL-1 beta were also significantly elevated in nonlaboring patients with BV. Mutat Res, 1997 Mar, 386(1), 1 - 23 Recent advances in the construction of bacterial genotoxicity assays; Josephy PD et al.; Bacterial mutagenicity assays have been widely used in genotoxicology research for two decades . We discuss the development of such assays, especially the Ames test, with particular attention to strain engineering . Genes encoding enzymes of mutagen bioactivation, including N-acetyltransferase, nitroreductase, and cytochrome P450, have been introduced into tester strains . The processing of DNA damage by the bacterial strains has also been modified in several ways, so as to enhance mutagenesis . These efforts have greatly increased the sensitivity of mutation assays and have illuminated the molecular mechanisms of mutagenesis . We also discuss the relationship between bacterial assays and in vivo mutation assays which use transgenic rodents. JPEN J Parenter Enteral Nutr, 1997 Mar-Apr, 21(2), 75 - 80 Role of glutamine in bacterial transcytosis and epithelial cell injury; Panigrahi P et al.; BACKGROUND: L-Glutamine is the principal energy source for small intestinal enterocytes . Diminution of intestinal function, mucosal atrophy, and increased bacterial translocation have been noted during total parenteral nutrition (TPN) . In a rat model of glutamine starvation, we previously showed that luminal glutamine is essential for optimal intestinal function . In this study, we examined the effect of apical vs basolateral glutamine on bacterial translocation in a Caco-2 cell culture system and bacteria-induced tissue injury in a weanling rabbit ileal loop model . METHODS: Caco-2 cells were grown in a transwell system . After confluence, apical and basolateral chambers received defined media, and glutamine deprivation was carried out over a 4- to 48-hour period . Escherichia coli transcytosis and structure/function studies were then performed . In a second series of experiments, the effect of intraluminal glutamine supplementation was evaluated in an E . coli-induced tissue injury model in weanling rabbit ileal loops . RESULTS: Expression of disaccharidases, glucoamylase, and Na+/K(+)-adenosine 5'-triphosphatase (ATPase) were significantly reduced when cells were deprived of glutamine from the apical side, and there was increased bacterial translocation across the monolayer . Transepithelial epithelial resistance (TEER) across the monolayer was also reduced in the glutamine-free cultures . Glutamine replenishment over 24 to 48 hours restored the original functions . Basolateral deprivation had a smaller effect on the Caco-2 cells . Typical necrotic mucosal injury caused by E . coli in the ileal loops was blocked by co-infiltration of the loops with glutamine . CONCLUSIONS: This study demonstrates for the first time that the supply of glutamine from the apical side is of critical importance for maintaining optimal structure and function of the enterocytes . The effects are not acute or energy related . These observations have important clinical implications in the management of patients under critical care, including premature infants and patients receiving TPN, for whom lack of glutamine from the luminal side could produce mucosal dysfunction, resulting ultimately in severe atrophic/necrotic complications. Eur J Immunol, 1997 Mar, 27(3), 772 - 81 Carboxy-terminal residues of major histocompatibility complex class II-associated peptides control the presentation of the bacterial superantigen toxic shock syndrome toxin-1 to T cells; Wen R et al.; Previous studies have shown that the presentation of some bacterial superantigens by major histocompatibility complex (MHC) class II molecules is strongly influenced by class II-associated peptides . For example, presentation of the toxic shock syndrome toxin-1 (TSST-1) superantigen by antigen-processing-defective T2-I-Ab cells (which expresses I-Ab that is either empty or associated with invariant chain-derived peptides) can be strongly enhanced by some, but not other, I-Ab-binding peptides . Here we investigate the contribution of I-Ab-associated peptides in the presentation of TSST-1 to T cells . The data show that overlapping peptides expressing the same core I-Ab-restricted epitope, but with various N and C termini, can differ profoundly in their ability to promote TSST-1 presentation to T cells . Analysis of altered and truncated peptides indicates that residues at the C-terminal end of the peptide have a dramatic effect on TSST-1 presentation . This effect does not involve a cognate interaction between the peptide and the TSST-1 molecule, but appears to depend on the length of the C-terminal region . These data are consistent with crystallographic studies suggesting that TSST-1 may interact with the C-terminal residues of MHC class II-associated peptides . We also examined the capacity of naturally processed peptides to promote TSST-1 binding using a superantigen blocking assay . The data demonstrated that a naturally processed epitope is dominated by peptides that do not promote strong TSST-1 binding to I-Ab . Taken together, these data suggest that TSST-1 binding to MHC class II molecules is controlled by the C-terminal residues of the associated peptide, and that many naturally processed peptide/class II complexes do not present TSST-1 to T cells . Thus, the peptide dependence of TSST-1 binding to class II molecules may significantly reduce the capacity of TSST-1 to stimulate T cells. Am J Obstet Gynecol, 1997 Mar, 176(3), 544 - 9 Bacterial lipopolysaccharide-mediated murine fetal death: the role of interleukin-1; Silver RM et al.; OBJECTIVE: Our purpose was to determine whether interleukin-1 is an important mediator of lipopolysaccharide-induced fetal death and, if so, whether interleukin-1 causes fetal death by inducing prostanoid formation in gestational tissues . STUDY DESIGN: Pregnant C3H/HeN mice were administered lipopolysaccharide, interleukin-1alpha, interleukin-beta, or vehicle on days 11 to 13 of pregnancy . Mice were killed 72 hours later and the fetal status was determined . Some mice were pretreated with anti-interleukin-1-receptor antibodies or indomethacin . Decidual explants were established from treated mice, and supernatants were assayed for interleukin-1beta and prostaglandin E2 . RESULTS: Decidua taken from lipopolysaccharide-treated mice produced significantly increased amounts of interleukin-1beta, and pretreatment with anti-interleukin-1-receptor antibodies reduced the proportion of fetal deaths after lipopolysaccharide administration from 100% to 33% . The administration of interleukin-1alpha caused fetal death in a dose-dependent fashion, and decidua taken from interleukin-1-treated mice produced significantly increased amounts of prostaglandin E2 . However, pretreatment with doses of indomethacin that abrogated decidual prostaglandin E2 production did not reduce the proportion of fetal death after interleukin-1alpha administration . CONCLUSIONS: Interleukin-1 is an important mediator of lipopolysaccharide-induced fetal death and causes fetal death by prostaglandin-independent effects. Protein Sci, 1997 Mar, 6(3), 628 - 36 Residues in the alpha helix 7 of the bacterial maltose binding protein which are important in interactions with the Mal FGK2 complex; Szmelcman S et al.; The periplasmic maltose binding protein, MalE, is a major element in maltose transport and in chemotaxis towards this sugar . Previous genetic analysis of the MalE protein revealed functional domains involved in transport and chemotactic functions . Among them the surface located alpha helix 7, which is part of the C-lobe, one of the two lobes forming the three dimensional structure of MalE . Small deletions in this region abolished maltose transport, although maintaining wild-type affinity and specificity as well as a normal chemoreceptor function . It was suggested that alpha helix 7 may be implicated in interactions between the maltose binding protein and the membrane-bound protein complex (Duplay P, Szmelcman S . 1987 . Silent and functional changes in the periplasmic maltose binding protein of Escherichia coli K12 . II . Chemotaxis towards maltose . J Mol Biol 194:675-678: Duplay P, Szmelcman S, Bedouelle H, Hofnung M . 1987 . Silent and functional changes in the periplasmic maltose binding protein of Escherichia coli K12 . I: Transport of maltose . J Mol Biol 194:663-673) . In this study, we submitted a region of 14 residues--Asp 207 to Gly 220--encompassing alpha helix 7, to genetic analysis by oligonucleotide mediated random mutagenesis . Out of 127 identified mutations, twelve single and five double mutants with normal affinities towards maltose were selected for further investigation . Two types of mutations were characterized, silent mutations that did not affect maltose transport and mutations that heavily impaired transport kinetics, even thought the maltose binding capacity of the mutant proteins remained normal . Three substitutions at Tyr 210 (Y210S, Y210L, Y210N) drastically reduced maltose transport . One substitution at Ala 213 (A213I) and one substitution at Glu 214 (E214K) also impaired transport . These three identified residues, Tyr 210, Ala 213, and Glu 214, which are constituents of alpha helix 7, therefore seem to play some important role in maltose transport, most probably in a productive interaction between the MalE protein and the membrane bound MalFGK2 complex. Genetics, 1997 Mar, 145(3), 573 - 85 Gain-of-function mutations in TnsC, an ATP-dependent transposition protein that activates the bacterial transposon Tn7; Stellwagen AE et al.; The bacterial transposon Tn7 encodes five genes whose protein products are used in different combinations to direct transposition to different types of target sites . TnsABC + D directs transposition to a specific site in the Escherichia coli chromosome called attTn7, whereas TnsABC + E directs transposition to non-attTn7 sites . These transposition reactions can also recognize and avoid "immune" targets that already contain a copy of Tn7 . TnsD and TnsE are required to activate TnsABC as well as to select a target site; no transposition occurs with wild-type TnsABC alone . Here, we describe the isolation of TnsC gain-of-function mutants that activate the TnsA+B transposase in the absence of TnsD or TnsE . Some of these TnsC mutants enable the TnsABC machinery to execute transposition without sacrificing its ability to discriminate between different types of targets . Other TnsC mutants appear to constitutively activate the TnsABC machinery so that it bypasses target signals . We also present experiments that suggest that target selection occurs early in the Tn7 transposition pathway in vivo: favorable attTn7 targets appear to promote the excision of Tn7 from the chromosome, whereas immune targets do not allow transposon excision to occur . This work supports the view that TnsC plays a central role in the evaluation and utilization of target DNAs. Hepatology, 1997 Mar, 25(3), 532 - 6 Continuous versus inpatient prophylaxis of the first episode of spontaneous bacterial peritonitis with norfloxacin; Novella M et al.; Cirrhotic patients with ascites and low ascitic fluid total protein and/or high serum bilirubin levels are at high risk to develop the first episode of spontaneous bacterial peritonitis during long-term follow-up . The aim of the present study was to determine the efficacy of continuous long-term selective intestinal decontamination with norfloxacin in the prevention of this complication . One hundred nine cirrhotic patients with ascites and ascitic fluid total protein levels of < or = 1 g/dL or serum bilirubin levels of > 2.5 mg/dL without previous spontaneous bacterial peritonitis were prospectively randomized into two groups: group 1 (n = 56) received norfloxacin, 400 mg daily administered orally, and group 2 (n = 53) was the long-term control group, receiving norfloxacin only during hospitalization . During a mean follow-up of 43 +/- 3 weeks, there was one spontaneous bacterial peritonitis (1.8%) in group 1 and 9 (16.9%) in group 2 (P < .01) . The incidence of community-acquired spontaneous bacterial peritonitis was lower in group 1 (1.8% vs . 13.2%, P < .05), whereas the incidence of nosocomial spontaneous bacterial peritonitis (0% vs . 3.7%) and the incidence of extraperitoneal infections (25% vs . 24.5%) were similar in both groups (P = NS) . The actuarial probability of survival at 18 months was 75% in group 1 and 62% in group 2 (P = NS) . Resistance to norfloxacin was observed in 9 of 10 (90%) Escherichia coli isolated in infections from group 1 and in 4 of 11 (36.3%) from group 2 (P < .05) . The overall incidence of infections caused by norfloxacin-resistant bacteria was higher in group 1 (19.6% vs . 15%), but it did not reach statistical significance . Continuous long-term selective intestinal decontamination with norfloxacin is effective in preventing the first spontaneous bacterial peritonitis in cirrhotic patients at high risk . However, the emergence of infections caused by norfloxacin-resistant bacteria must be weighed carefully against the benefits of continuous long-term prophylaxis. Biochemistry, 1997 Feb 25, 36(8), 2030 - 40 Kinetic characterization of phosphotransfer between CheA and CheY in the bacterial chemotaxis signal transduction pathway; Stewart RC; Phosphorylation of the CheY protein is a crucial step in the chemotaxis signal transduction pathway of Escherichia coli . CheY becomes phosphorylated by acquiring a phosphoryl group from CheA, an autophosphorylating protein kinase . In this study, we utilized a rapid-quench instrument to investigate the kinetics of phosphotransfer in single-turnover experiments . Our results are consistent with a three-step mechanism for the CheA-to-CheY phosphotransfer reaction: (i) reversible binding of CheY to P-CheA; (ii) rapid, reversible phosphotransfer to CheY; (iii) reversible dissociation of the resulting CheA x CheY-P complex . Investigation of the effect of CheY concentration on the observed rate of phosphotransfer demonstrated saturation kinetics; the extrapolated limiting rate constant for phosphotransfer was 650 +/- 200 s(-1), while the Km value indicated from this work was 6.5 +/- 2 microM . We demonstrated that the CheA-CheY phosphotransfer reaction was reversible by observing partial transfer of {32P}phosphate from CheY-P to CheA and by observing the effect of high concentrations of unphosphorylated CheA on the equilibrium: P-CheA + CheY <--> CheA + CheY-P . We found that the rate of phosphotransfer from P-CheA to CheY can be inhibited by unphosphorylated CheA as well as by a fragment of CheA (CheA124-257) that contains the CheY binding site; these results suggest that the unphosphorylated form of CheA can effectively compete with P-CheA for available CheY (Kd approximately 1.5 +/- 0.6 microM for the CheY x CheA124-257 complex and for the CheY x CheA complex). Biochemistry, 1997 Feb 18, 36(7), 1699 - 703 Solid-state REDOR NMR distance measurements at the ligand site of a bacterial chemotaxis membrane receptor; Wang J et al.; The Escherichia coli serine receptor senses serine levels in the environment and transmits this information across the bacterial inner membrane to modulate a protein phosphorylation cascade which controls swimming behavior . Solid-state nuclear magnetic resonance (NMR) has been used to characterize specific structural features of the ligand binding site interactions in the intact, membrane-bound Ser receptor . Rotational-echo double-resonance (REDOR) experiments on {15N}Ser bound to a {1-13C}Phe-receptor preparation are used to measure distances between the ligand amino group and the carbonyls of two phenylalanine residues in the ligand binding pocket . The results indicate two 4.0 +/- 0.2 A distances, in excellent agreement with the X-ray crystal structure of a soluble fragment of the homologous aspartate receptor {Milburn et al . (1991) Science 254, 1342-1347} . These results confirm the similarity of the binding sites of the Asp and Ser receptors, and demonstrate the feasibility of using solid-state NMR measurements to obtain specific structural information on the 120 kDa intact receptor for probing transmembrane signaling mechanisms. J Immunol, 1997 Feb 15, 158(4), 1956 - 64 C-X-C and C-C chemokines are expressed in the cerebrospinal fluid in bacterial meningitis and mediate chemotactic activity on peripheral blood-derived polymorphonuclear and mononuclear cells in vitro; Spanaus KS et al.; The appearance of polymorphonuclear and mononuclear leukocytes in the cerebrospinal fluid (csf) is an important hallmark of bacterial meningitis . Chemokines are candidate mediators of cell migration from blood into the subarachnoid space . Therefore, concentrations of C-X-C and C-C chemokines in the csf of patients with pyogenic meningitis were measured by ELISA . Highly significant elevations of chemokine levels in comparison with noninflammatory csf controls were found for IL-8 (median, 21.6 ng/ml; range, < 0.1 to 191.3), growth-related gene product alpha (median, 5.6 ng/ml; range, < 0.1 to 48.2), monocyte chemotactic protein-1 (median, 26.4 ng/ml; range, < 0.2 to 193.8), macrophage inflammatory protein-1 alpha (MIP-1 alpha; median, 1.8 ng/ml; range, < 0.5 to 18.0), MIP-1 beta (median, 10.6 ng/ml; range, < 0.3 to 84.4), but not for RANTES (regulated upon activation, normal T cell expressed and secreted) . The csf of bacterial meningitis were chemotactic for neutrophils and mononuclear leukocytes . Correlation analysis demonstrated a strong association between individual chemokine levels and chemotactic activity mediated by csf . A significant reduction of neutrophil chemotaxis was obtained by anti-IL-8 and anti-growth-related gene product alpha Abs, and a reduction of mononuclear cell migration was achieved by a combination of anti-monocyte chemotactic protein-1, anti-MIP-1 alpha, and anti-MIP-1 beta Abs . Since no significant correlation was found between csf leukocyte counts and chemokine concentrations or chemotactic activity mediated by csf, additional factors influence the extent of pleocytosis in vivo. Cell, 1997 Feb 7, 88(3), 417 - 26 Secretory leukocyte protease inhibitor: a macrophage product induced by and antagonistic to bacterial lipopolysaccharide; Jin FY et al.; To explore regulation of potentially lethal responses to bacterial lipopolysaccharide (LPS), we used differential display under LPS-free conditions to compare macrophage cell lines from two strains of mice congenic for a locus affecting LPS sensitivity . LPS-hyporesponsive cells, primary macrophages, and polymorphonuclear leukocytes transcribed secretory leukocyte protease inhibitor (SLPI), a known epithelial cell-derived inhibitor of leukocyte serine proteases . Transfection of macrophages with SLPI suppressed LPS-induced activation of NF-kappa B and production of nitric oxide and TNF alpha . The ability of interferon-gamma (IFN gamma) to restore LPS responsiveness is a hallmark of the LPS-hyporesponsive phenotype . IFN gamma suppressed expression of SLPI and restored LPS responsiveness to SLPI-producing cells . Thus, SLPI is an LPS-induced IFN gamma-suppressible phagocyte product that serves to inhibit LPS responses. J Exp Med, 1997 Feb 3, 185(3), 579 - 82 Purinergic modulation of interleukin-1 beta release from microglial cells stimulated with bacterial endotoxin; Ferrari D et al.; Microglial cells express a peculiar plasma membrane receptor for extracellular ATP, named P2Z/P2X7 purinergic receptor, that triggers massive transmembrane ion fluxes and a reversible permeabilization of the plasma membrane to hydrophylic molecules of up to 900 dalton molecule weight and eventual cell death (Di Virgilio, F . 1995 . Immunol . Today, 16:524-528) . The physiological role of this newly cloned (Surprenant, A., F . Rassendren, E . Kawashima, R . A . North and G . Buell, 1996 . Science (Wash . DC) . 272:735-737) cytolytic receptor is unknown . In vitro and in vivo activation of the macrophage and microglial cell P2Z/P2X7 receptor by exogenous ATP causes a large and rapid release of mature IL-1 beta . In the present report we investigated the role of microglial P2Z/P2X7 receptor in IL-1 beta release triggered by LPS . Our data suggest that LPS-dependent IL-1 beta release involves activation of this purinergic receptor as it is inhibited by the selective P2Z/P2X7 blocker oxidized ATP and modulated by ATP-hydrolyzing enzymes such as apyrase or hexokinase . Furthermore, microglial cells release ATP when stimulated with LPS . LPS-dependent release of ATP is also observed in monocyte-derived human macrophages . It is suggested that bacterial endotoxin activates an autocrine/paracrine loop that drives ATP-dependent IL-1 beta secretion. Braz J Med Biol Res, 1997 Feb, 30(2), 207 - 11 Effect of bacterial lipopolysaccharide on gastric emptying of liquids in rats; Collares EF; The objectives of the present investigation were 1) to study the effect of bacterial lipopolysaccharide (LPS) on rat gastric emptying (GE) and 2) to investigate a possible involvement of the vagus nerve in the gastric action of LPS . Endotoxin from E . coli (strain 055:B5) was administered sc, ip or iv to male Wistar rats (220-280 g body weight) at a maximum dose of 50 micrograms/kg animal weight . Control animals received an equivalent volume of sterile saline solution . At a given time period after LPS administration, GE was evaluated by measuring gastric retention 10 min after the orogastric infusion of a test meal (2 ml/100 g animal weight), which consisted of 0.9% NaCl plus the marker phenol red (6 mg/dl) . One group of animals was subjected to bilateral subdiaphragmatic vagotomy or sham operation 15 days before the test . A significant delay in GE of the test meal was observed 5 h after iv administration of the endotoxin at the dose of 50 micrograms/kg animal weight . The LPS-induced delay of GE was detected as early as 30 min and up to 8 h after endotoxin administration . The use of different doses of LPS ranging from 5 to 50 micrograms/kg animal weight showed that the alteration of GE was dose dependent . In addition, vagotomized animals receiving LPS displayed a GE that was not significantly different from that of the sham control group . However, a participation of the vagus nerve in LPS-induced delay in GE could not be clearly demonstrated by these experiments since vagotomy itself induced changes in this gastric parameter . The present study provides a suitable model for identifying the mechanisms underlying the effects of LPS on gastric emptying. J Infect Dis, 1997 Feb, 175(2), 406 - 13 Evidence for a commensal, symbiotic relationship between Gardnerella vaginalis and Prevotella bivia involving ammonia: potential significance for bacterial vaginosis; Pybus V et al.; Six strains of Prevotella bivia and 4 of Gardnerella vaginalis were examined for nutrient substrate utilization as part of ongoing studies on the pathogenesis of bacterial vaginosis . Addition of single amino acids to vaginal defined medium (VDM) was stimulatory to the growth of P . bivia but not to G . vaginalis . However, peptides significantly promoted the growth of both organisms . Growth of P . bivia in VDM and VDM supplemented with either amino acids or peptone was accompanied by net ammonia production, while growth of G . vaginalis under the same conditions resulted in net ammonia utilization . Ammonia-enriched supernatants from the growth of P . bivia in peptone-supplemented VDM were stimulatory to G . vaginalis growth . However, ammonia-reduced supernatants from G . vaginalis growth in peptone-supplemented VDM had a neutral effect on P . bivia growth . A commensal relationship between P . bivia to G . vaginalis is proposed, with ammonia flow as a mechanism to support this hypothesis. Inflammation, 1997 Feb, 21(1), 113 - 31 Cytokine and nitric oxide production in the acute phase of bacterial cell wall-induced arthritis; Fuseler JW et al.; We have investigated the temporal relationship among proinflammatory cytokine expression, nitric oxide (NO) production and joint inflammation in the acute phase of bacterial cell wall-derived peptidoglycan polysaccharide (PG/PS)-induced arthritis . Acute joint inflammation was induced in female LEW/N rats by a single intraperitoneal injection of PG/PS . Arthritis index and paw volume were quantified and joint histopathology was evaluated during acute joint inflammation (0-10 days) . Tumor necrosis factor (TNF), interleukin-1 (IL-1) and interleukin-6 (IL-6) were determined by bioassay whereas nitric oxide (NO) was quantified by measuring serum nitrate/nitrite levels via the Griess procedure . We found that serum levels of TNF and serum IL-1 preceded the increase in IL-6 and NO production . Furthermore, the production of these proinflammatory cytokines and NO preceded bone erosion and osteoclast activity . Erosion of subchondral bone preceded pannus formation and cellular synovitis in the acute phase of PG/PS-induced arthritis . The temporal expression of TNF, IL-1, IL-6 and NO suggest a cascade of inflammatory mediators in which monocytes and macrophages respond to PG/PS with enhanced synthesis of TNF and IL-1, which may in turn promote the synthesis of IL-6 and NO . We postulate that one or more of these inflammatory events are responsible for initiating the subchondral bone erosion observed in acute joint inflammation. Bioorg Khim, 1997 Feb, 23(2), 118 - 26 {Bacterial synthesis of immunogenic epitopes of foot-and-mouth disease virus fused either to human necrosis factor or to hepatitis B core antigen}; Nekrasova OV et al.; Using recombinant DNA technology, construction and bacterial expression of genes was carried out which code for hybrid proteins, human tumor necrosis factor and hepatitis B core protein fused to immunogenic epitopes of foot-and-mouth disease virus, strains A22 and O1-194 . Hybrids of tumor necrosis factor with foot-and-mouth disease antigenic determinants protected laboratory animals against the experimental challenge with a homologous strain of foot-and-mouth disease virus . Hybrid protein that contained immunogenic regions of two strains, A22 and O1-194, protected animals against infection with both A and O serotypes . Hybrid proteins based on hepatitis B virus core antigen retained the ability to assemble into core-like particles. J Biochem Biophys Methods, 1997 Feb 1, 34(1), 69 - 71 Rapid detection of bacterial surface proteins using an enzyme-linked immunosorbent assay system; Burkovski A; In this communication a rapid and simple enzyme-linked immunosorbent assay is described, suitable for the investigation of bacterial surface proteins . The protocol uses whole cells and avoids any centrifugation or cross-linking steps . Less than 10(6) cells were detected by this procedure. Gene Ther, 1997 Feb, 4(2), 93 - 100 The expression of bacterial nitroreductase in transgenic mice results in specific cell killing by the prodrug CB1954; Drabek D et al.; The enzyme nitroreductase, isolated from Escherichia coli B, converts CB1954 ((5-aziridin-1-yl)-2,4-dinitro-benzamide) into a cytotoxic DNA interstrand cross-linking agent . The E . coli B gene (nfnB, NTR) encoding nitroreductase (NTR) was cloned into eukaryotic expression vectors . When driven by a CMV promoter, 5-10% of the stably transfected mouse fibroblasts expressed the NTR enzyme . These cells were killed at a concentration of 20 microM CB1954 in comparison to nonexpressing cells which were killed at a much higher concentration (500 microM) . We subsequently generated transgenic mice to test the prodrug system in vivo . Nitroreductase was expressed specifically in T cells driven by the control elements of the human CD2 locus . Upon CB1954 treatment, transgenic mice show extensive cell depletion in thymus and spleen (14-16% of normal cell numbers), whereas all other tissues are unaffected by prodrug administration . These results raise the possibility of using the NTR gene in anticancer therapy. Arch Dis Child, 1997 Feb, 76(2), 139 - 40 Cochlear implantation after bacterial meningitis: the dangers of delay; Dodds A et al.; A case is described of a child of 2.6 years who developed total deafness after acute bacterial meningitis . Rapid obliteration of the cochleas due to osteoneogenesis led to limited cochlear implantation . The case is made for fast tracking these children to cochlear implant teams before neoossification becomes established. Eur J Biochem, 1997 Feb 1, 243(3), 762 - 9 Cloning, bacterial expression and biological characterization of recombinant human granulocyte chemotactic protein-2 and differential expression of granulocyte chemotactic protein-2 and epithelial cell-derived neutrophil activating peptide-78 mRNAs; Froyen G et al.; Human osteosarcoma cells secrete a novel C-X-C chemokine called granulocyte chemotactic protein-2 (GCP-2), which was previously identified by amino acid sequencing of the purified natural protein . In order to understand the role of this new protein in inflammatory reactions, we cloned GCP-2 DNA sequences to generate recombinant protein and specific DNA probes and primers . By means of PCR on cloned cDNA of osteosarcoma cells induced by interleukin-1 beta and fibroblasts induced by lipopolysaccharide plus dsRNA, the complete coding domain of GCP-2 was isolated . This sequence was cloned into the bacterial expression vector pHEN1 and, after induction, GCP-2 was secreted into the periplasm of Escherichia coli . Recombinant GCP-2 (rGCP-2) was purified and characterized by SDS/PAGE as a monomeric 6.5-kDa protein and by amino-terminal sequencing . The chemoattractive potency of GCP-2 for neutrophilic granulocytes was about 10-times less than that of interleukin-8 and the minimal effective dose was 10 ng/ml . However, at optimal dose (100 ng/ml) the maximal chemotactic response was comparable with that of interleukin-8 . Both characteristics correspond with those of natural GCP-2 . In addition, intracellular calcium release in neutrophils by recombinant GCP-2 was achieved with as little as 10 ng/ml . Quantitation studies using reverse transcriptase and the polymerase chain reaction revealed higher GCP-2 mRNA production in normal fibroblasts than in tumor cells . When compared with epithelial-cell-derived neutrophil-activating peptide-78 (ENA-78) mRNA, the GCP-2 mRNA levels were higher in all cell lines tested . In addition, GCP-2 and ENA-78 expression seem to be differentially regulated in that phorbol ester and lipopolysaccharide have opposing effects on their mRNA induction in diploid fibroblasts and epithelial cells, respectively . Interleukin-1 was demonstrated to be a general inducer for both chemokines, while interferon-gamma down-regulates their mRNA expression . The availability of recombinant GCP-2 together with the quantitation studies on mRNA expression will help to further elucidate the biological role of GCP-2 during the inflammatory response. Transfusion, 1997 Feb, 37(2), 126 - 34 Transfusion of red cells is associated with increased incidence of bacterial infection after colorectal surgery: a prospective study; Houbiers JG et al.; BACKGROUND: Several studies suggest that perioperative blood transfusion is a major independent risk factor for postoperative bacterial infections . Transfusion-induced immunosuppression is thought to mediate this effect . STUDY DESIGN AND METHODS: In a randomized clinical trial comprising 697 patients with colorectal cancer, the relationship between two types of red cell components (buffy coat-depleted packed red cells and white cell-reduced {filtered} packed red cells) and postoperative bacterial infections was analyzed . RESULTS: Both types of red cells appeared to be associated with a greater incidence of postoperative infection than was no transfusion (39 vs . 24%, p < 0.01) . A dose-response relationship could be demonstrated: the corrected relative risk was 1.6 for 1 to 3 units of red cells and 3.6 for more than 3 units . Multivariate analyses identified the transfusion of red cells and tumor location as the only significant independent risk factors for postoperative bacterial infection . CONCLUSION: Because allogeneic white cells, plasma, microaggregates, citrate, and platelets could be ruled out as risk factors for transfusion-associated postoperative infections, it is hypothesized that the transfusion of red cells is a potentially detrimental factor that transiently impairs the clearance of bacteria by phagocytic cells. Mol Microbiol, 1997 Feb, 23(3), 617 - 26 Structure of TolC, the outer membrane component of the bacterial type I efflux system, derived from two-dimensional crystals; Koronakis V et al.; TolC is an outer membrane protein required for the export of virulence proteins and toxic compounds without a periplasmic intermediate . We show that TolC is an integral part of the translocator, interacting with inner membrane components, by demonstrating a need for TolC in protein export not only from intact cells but also from sphaeroplasts . To establish the structure of TolC, and thus gain information on how this might be achieved, the protein was purified from the Escherichia coli outer membrane, as a trimer, and crystallized in two-dimensional lattices by reconstitution in phospholipid bilayers . The projection structure at 12A resolution showed a threefold symmetric molecule of 58A outer diameter, and a single pool of stain filling its centre . Side views parallel to the membrane plane revealed an additional domain outside the membrane . Eighteen membrane-spanning beta-strands were predicted for the 51.5 kDa monomer, excluding a 7 kDa C-terminal segment, and this segment was shown to contain a proteinase K-sensitive site that was exposed in reconstituted membranes and sphaeroplasts, but which was protected in intact cells . The combined data suggest that TolC is a trimeric outer membrane protein with each monomer comprising a membrane domain, predicted to be beta-barrel, and a C-terminal periplasmic domain . The latter could form part of the bridge to the energized inner membrane component of the translocation complex. J Pediatr Surg, 1997 Feb, 32(2), 312 - 5 Interleukin-11 improves survival and reduces bacterial translocation and bone marrow suppression in burned mice; Schindel D et al.; PURPOSE: Major burns are associated with a high mortality, an increased rate of bacterial translocation, and bone marrow suppression . This study evaluates the effect of interleukin-11 (IL-11), a bone marrow-derived growth factor on survival, intestinal cytoarchitecture, bacterial translocation, and bone marrow suppression in a highly lethal murine burn model with a lethal dose greater than 50 . METHODS: C3H/HeJ 8 to 10-week-old mice underwent a standardized 32% total body surface area (TBSA) scald burn using a burn template . Mice were divided equally between groups receiving IL-11 (125 micrograms/kg, twice daily, subcutaneously {SC}) and 0.1% same-volume Bovine Serum Albumin (BSA) (0.2 mL, twice daily, sc) . Animals were evaluated for mesenteric lymph node bacterial counts, intestinal mucosal villus height, number of mucosal crypt cell mitoses per 100 crypts, and peripheral platelet and total lymphocyte counts . Survival was calculated to 7 days postburn . RESULTS: At 24 hours postburn, IL-11-treated mice had significantly less enteric bacteria cultured from mesenteric lymph nodes (P < .001), increased intestinal crypt cell mitoses (P = .002) and intestinal villus height (P = .002), increased peripheral platelet (P = .002) and lymphocyte counts (P = .004), and an improved survival compared with BSA controls (P = .003) . CONCLUSION: These data show that IL-11 improves survival, intestinal cytoarchitecture, reduces bacterial translocation, and reduces bone marrow suppression after a 32% TBSA burn in mice . These data imply that IL-11 cytokine therapy may be a useful adjunct in extensive burn injury. Protein Sci, 1997 Feb, 6(2), 315 - 22 Analysis of protein structure in intact cells: crosslinking in vivo between introduced cysteines in the transmembrane domain of a bacterial chemoreceptor; Hughson AG et al.; Oxidative crosslinking of cysteines introduced by site-specific mutagenesis is a powerful tool for structural analysis of proteins, but the approach has been limited to studies in vitro . We recently reported that intact cells of Escherichia coli could be treated with Cu(II)-(o-phenanthroline)3 or molecular iodine in a way that left unperturbed flagellar function or general chemotactic response, yet crosslinks were quantitatively formed between select cysteines in adjoining transmembrane helices of chemoreceptor Trg . This suggested that oxidative crosslinking might be utilized for structural analysis in vivo . Thus, we used our comprehensive collection of Trg derivatives, each containing a single cysteine at one of the 54 positions in the two transmembrane segments of the receptor monomer to characterize patterns of crosslinking in vivo and in vitro for this homodimeric protein . We found that in vivo crosslinking compared favorably as a technique for structural analysis with the more conventional in vitro approach . Patterns of crosslinking generated by oxidation treatments of intact cells indicated extensive interaction of transmembrane segment 1 (TM1) with its homologous partner (TM1') in the other subunit and a more distant placement of TM2 and TM2', the same relationships identified by crosslinking in isolated membranes . In addition, the same helical faces for TM1-TM1' interaction and TM2-TM2' orientation were identified in vivo and in vitro . The correspondence of the patterns also indicates that structural features identified by analysis of in vitro crosslinking are relevant to the organization of the chemoreceptor in its native environment, the intact, functional cell . It appears that the different features of the two functionally benign treatments used for in vivo oxidations can provide insights into protein dynamics. Pediatr Res, 1997 Feb, 41(2), 235 - 41 Increased activity of lysosomal acid hydrolases in the cell-free cerebrospinal fluid of bacterial meningitis; Beratis NG et al.; Because inflammation could affect lysosomal enzyme trafficking, resulting in increased enzyme release from the cells, tissue necrosis, or altered blood- and the brain-cerebrospinal fluid (CSF) barrier, the activity of four lysosomal enzymes in the cell-free CSF of 34 patients with bacterial meningitis, 20 with aseptic meningitis, and 39 control subjects was measured . Activities are expressed in nanomoles of 4-methylumbelliferone mL/h . The median beta-hexosaminidase A activity in bacterial meningitis was 313, in aseptic meningitis it was 173, and in the control subjects it was 175, the median beta-hexosaminidase B activity was 417, 165, and 120; the median alpha-mannosidase activity was 171, 124, and 113; and the median beta-glucuronidase activity was 133.7, 14.3, and 10.0, respectively . The difference of the activities of the four enzymes measured between the bacteria meningitis and the controls is significant (p < 0.000) . Also significant is the difference between bacterial and aseptic meningitis (p = 0.005 to < 0.000), but it is not significant between aseptic and control subjects . Both the sensitivity and specificity of the beta-glucuronidase activity between bacterial meningitis and control subjects were 100%, whereas the corresponding values between bacterial and aseptic meningitis were 100% and 90%, respectively . No significant correlation was observed between the activities of the enzymes measured and the number of the polymorphonuclear leukocytes or other laboratory characteristics of the CSF . The increased lysosomal enzyme activities in the CSF of patients with meningitis may result from diffusion across the blood-CSF or the brain-CSF barrier or from enzyme leakage through the cell membranes. J Bacteriol, 1997 Feb, 179(4), 1404 - 8 Identification of the epitope for a highly cross-reactive monoclonal antibody on the major sigma factor of bacterial RNA polymerase; Breyer MJ et al.; A highly cross-reactive monoclonal antibody (MAb), 2G10, was found to react in a conserved region of Escherichia coli RNA polymerase sigma70 . The epitope was localized to amino acids 470 to 486, which included part of conserved region 3.1 . The epitope for MAb 3D3, a MAb which maps close to the 2G10 epitope, was also determined. Infect Immun, 1997 Feb, 65(2), 699 - 707 Cytokine and adhesion molecule expression in human monocytes and endothelial cells stimulated with bacterial heat shock proteins; Galdiero M et al.; Bacterial heat shock proteins (HSPs) from Escherichia coli (GroES, GroEL, and DNAk) were tested for their ability to induce by themselves the expression and release of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and granulocyte-monocyte colony-stimulating factor (GM-CSF) by human monocytes and GM-CSF, IL-6, E-selectin, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) by human umbilical vein endothelial cells (HUVEC) . Our study demonstrated that treatment of monocytes with DNAk increased IL-6, TNF-alpha, and GM-CSF release in a dose-dependent manner . The same effect was elicited by GroEL but at a lower rate . Treatment of HUVEC cultures with DNAk and GroEL also increased GM-CSF, IL-6, E-selectin, ICAM-1, and VCAM-1 release in a dose-dependent fashion . In any case, the greatest release was obtained by using DNAk and GroEL at a concentration of 1 microg/ml . DNAk and GroEL were also able to up-regulate the surface expression of E-selectin, ICAM-1, and VCAM-1 . As detected by reverse transcription-PCR analysis, DNAk and GroEL also increased the steady-state levels of cytokines and adhesion molecules in human monocytes and endothelial cells . In our study GroES showed a significant activity only on the release, surface expression, and mRNA transcription of E-selectin . Adhesion molecule expression seems to be a direct effect of HSPs and not via cytokines . Furthermore, these effects are due to HSPs properties because they are inhibited by specific monoclonal antibodies . These findings support the potential role of HSPs in modulating cell interactions during immunological and inflammatory responses. Cancer Lett, 1997 Jan 30, 112(2), 191 - 8 Sequential observation of micrometastasis formation by bacterial lacZ gene-tagged Lewis lung carcinoma cells; Kobayashi K et al.; Sequential events in micrometastasis formation including entry into the blood circulation and arrest, extravasation and initial growth in the lung was investigated using bacterial lacZ gene-tagged Lewis lung carcinoma cells (4A1-1) . Micrometastases in the lung could thereby be specifically detected at the single cell level by X-Gal staining . After intravenous injection, X-Gal positive tumor cells appeared to extravasate within hours, but most cells then degenerated or died in the alveolar space by 2-3 days postinjection . A decreased BrdU labeling index to a negligible level at 2 days postinjection and reduction of X-Gal positive foci to a basal level (less than 0.1% of injected cells) by 4 days are in line with rapid clearance of tumor cells from the lung . The size and BrdU labeling indices of the persisting X-Gal positive foci, however, started to increase from 4 days postinjection . Type IV collagen immunostaining demonstrated loss of pre-existing basement membranes with growth of micrometastases: When 4A1-1 cells were inoculated subcutaneously, lung micrometastases from resulting tumors were detected as single or small numbers of X-Gal positive cells at 2 weeks postinjection . Progressive development of micrometastasis to macroscopic metastasis was noted by 4-5 weeks postinjection . The results indicate that micrometastasis formation by Lewis lung carcinoma cells involves a sequence of events starting with rapid extravasation after arrest in the lung within 1 day, followed by death of most cells at 2-3 days and subsequent new growth and expansion of persisting tumor cells from 4 days postinjection. Eur J Pharmacol, 1997 Jan 29, 319(2-3), 273 - 8 Influence of pentoxifylline on fevers induced by bacterial lipopolysaccharide and tumor necrosis factor-alpha in guinea pigs; Goldbach JM et al.; In guinea pigs intraperitoneal (i.p.) injections of 50 mg/kg pentoxifylline had no influence on abdominal temperature while higher doses of pentoxifylline caused a hypothermic response lasting for 2-3 h . Administration of 50 mg/kg pentoxifylline 1 h before intramuscular (i.m.) injections of 20 micrograms/kg bacterial lipopolysaccharide reduced the lipopolysaccharide-induced production of endogenous tumor necrosis factor-alpha (TNF-alpha) by 68% . The second phase of lipopolysaccharide-induced fever was significantly attenuated by pretreatment with 50 mg/kg pentoxifylline, a dose which had, per se, no influence on core temperature of guinea pigs . The thermal response of guinea pigs to administration of exogenous TNF-alpha was not modulated by pretreatment with pentoxifylline . Intra-arterial infusions with 5 micrograms/kg TNF-alpha, a dose which yielded the same circulating TNF bioactivity as i.m . injections of 20 micrograms/kg lipopolysaccharide, induced a biphasic febrile response . The magnitude and duration of TNF-induced fever were the same whether guinea pigs were pretreated with pentoxifylline or with 0.9% saline . The results indicate that endogenous formation of TNF-alpha may contribute to the development of fever induced by lipopolysaccharide, but is not its only mediator, since the first phase of lipopolysaccharide-induced fever was not altered by the blockade of TNF production. Biochemistry, 1997 Jan 21, 36(3), 544 - 53 The tyrosine photophysics of a primase-derived peptide are sensitive to the peptide's zinc-bound state: proof that the bacterial primase hypothetical zinc finger sequence binds zinc; Griep MA et al.; A 35-amino acid peptide corresponding to the putative "zinc finger" sequence of primase was prepared to study its zinc binding properties . When zinc was added to the peptide, it was found that the fluorescence quantum yield of the single tyrosine increased by 46% and the average lifetime by 34% . The binding stoichiometry was one zinc per peptide . Below pH 6.0 and above pH 8.5, the zinc-peptide binding affinity was less than 1 microM and could be accurately determined . Interpolation from those binding constants suggested that the affinity at pH 7.5 was between 10 and 100 nM . The absorption spectrum of the cobalt(II)-peptide complex was consistent with tetrahedral metal coordination by three sulfur and one imidazole nitrogen ligands . The peptide affinity for cobalt was less than for zinc, indicating metal specificity . Analysis of the fluorescence intensity pH profile, circular dichroism spectra, the effect of extrinsic quenchers indicated that at neutral pH (1) the free peptide up into a structure to place the tyrosine in an environment protected from solvent, (2) the peptide bound zinc via its three cysteines and one of its histidines resulting in little change to the polypeptide secondary structure or to the tyrosine solvent accessibility, and (3) when the peptide bound zinc, it bound directly to or caused the immobilization of the groups that had been intramolecularly collisionally quenching the tyrosine which resulted in the observed increases in tyrosine quantum yield and lifetime. J Biol Chem, 1997 Jan 17, 272(3), 1595 - 600 Molecular cloning and characterization of Porphyromonas gingivalis lysine-specific gingipain . A new member of an emerging family of pathogenic bacterial cysteine proteinases; Pavloff N et al.; The proteinases of Porphyromonas gingivalis are key virulence factors in the etiology and progression of periodontal disease . Previous work in our laboratories resulted in the purification of arginine- and lysine-specific cysteine proteinases, designated gingipains, that consist of several tightly associated protein subunits . Recent characterization of arginine-specific gingipain-1 (gingipain R1; RGP-1) revealed that the sequence is unique and that the protein subunits are initially translated as a polyprotein encoding a proteinase domain and multiple adhesin domains (Pavloff, N., Potempa, J., Pike, R . N., Prochazka, V., Kiefer, M . C., Travis, J., and Barr, P . J . (1995) J . Biol . Chem . 270, 1007-1010) . We now show that the lysine-specific gingipain (gingipain K; KGP) is also biosynthesized as a polyprotein precursor that contains a proteinase domain that is 22% homologous to the proteinase domain of RGP-1 and multiple adhesin domains . This precursor is similarly processed at distinct sites to yield active KGP . The key catalytic residues in the proteinase domain of KGP are identical to those found in RGP-1, but there are significant differences elsewhere within this domain that likely contribute to the altered substrate specificity of KGP . Independent expression of the proteinase domain in insect cells has shown that KGP does not require the presence of the adhesin domains for correct folding to confer proteolytic activity. Eur Biophys J, 1997, 26(3), 261 - 70 Quartz crystal microbalance investigation of the interaction of bacterial toxins with ganglioside containing solid supported membranes; Janshoff A et al.; The binding of cholera toxin, tetanus toxin and pertussis toxin to ganglioside containing solid supported membranes has been investigated by quartz crystal microbalance measurements . The bilayers were prepared by fusion of phospholipid-vesicles on a hydrophobic monolayer of octanethiol chemisorbed on one gold electrode placed on the 5 MHz AT-cut quartz crystal . The ability of the gangliosides GM1, GM3, GD1a, GD1b, GT1b and asialo-GM1 to act as suitable receptors for the different toxins was tested by measuring the changes of quartz resonance frequencies . To obtain the binding constants of each ligand-receptor-couple Langmuir-isotherms were successfully fitted to the experimental adsorption isotherms . Cholera toxin shows a high affinity for GM1 (Ka = 1.8.10(8)M-1), a lower one for asialo-GM1 (Ka = 1.0.10(7)M-1) and no affinity for GM3 . The C-fragment of tetanus toxin binds to ganglioside GD1a, GD1b and GT1b containing membranes with similar affinity (Ka approximately 10(6)M-1), while no binding was observed with GM3 . Pertussis toxin binds to membranes containing the ganglioside GD1a with a binding constant of Ka = 1.6.10(6)M-1, but only if large amounts (40 mol%) of GD1a are present . The maximum frequency shift caused by the protein adsorption depends strongly on the molecular structure of the receptor . This is clearly demonstrated by an observed maximum frequency decrease of 99 Hz for the adsorption of the C-fragment of tetanus toxin to GD1b . In contrast to this large frequency decrease, which was unexpectedly high with respect to Sauerbrey's equation, implying pure mass loading, a maximum shift of only 28 Hz was detected after adsorption of the C-fragment of tetanus toxin to GD1a. Chir Narzadow Ruchu Ortop Pol, 1997, 62(2), 159 - 62 {Treatment of bacterial osteomyelitis using ultrasonic energy waves}; Gerber R et al.; The method and results of uncommon ultrasound treatment in 82 cases of osteomyelitis are presented . The method was supplemented with intraoperative Th 99m isotope diagnostics as well as fluorescence based diagnosis to identify necrotic bone fragments . Ultrasound energy had advantageous effect on soft tissue healing and osteogenesis. Acta Microbiol Pol, 1997, 46(1), 45 - 55 Bacterial growth and virulence factors production by different Bordetella pertussis strains; Letowska I et al.; The aim of this study was to compare bacteria growth and pertussis antigens (pertussis toxin-PT, filamentous haemagglutinin-FHA and endotoxin-LPS) production by 11 Bordetella pertussis strains . A synthetic Stainer-Scholte culture medium supplemented with (2,6-0-dimethyl) beta-cyclodextrin (heptakis) or methylcellulose (for greater PT and FHA production) and solid modified Cohen-Wheeler medium (for LPS isolation) were used . Our results demonstrated that heptakis and methylcellulose were more effective for antigens production than for bacterial growth . It was interesting that these stimulated substances supported the bacterial growth from small inocula . The investigated strains differed in PT, FHA and LPS production . The best PT producer was the B . pertussis 134 strain, the worst B . pertussis 2897 . The differences in FHA production are not as big as in PT production, but the B . pertussis 2897 was also the worst FHA producer . Isolated LPS consists of dry bacteria pellet ranging from 1,9% (B.p . Tohama) to 5,6% (B.p . 3803 strain) . No great differences in serological activity of LPS isolated from different strains were observed . In the haemagglutination inhibition test the endotoxin isolated from B.p . 509 and B.p . Tohama strains showed the highest activity. Dev Biol Stand, 1997, 90, 161 - 6 Immunization with bacterial antigens: piscirickettsiosis; Smith PA et al.; Piscirickettsiosis is a septicaemic disease of salmonid fish caused by the obligated intracellular rickettsia, Piscirickettsia salmonis . This disease was first reported in 1989 in salmon cultured in sea water netpens in southern Chile where it is still a major problem causing high mortality among cultured salmonids . In recent years related agents have been reported in farmed salmonids from Ireland, Canada and Norway . Mortality, however, at these locations has been reported to be low . Because of the recent description of piscirickettsiosis and its aetiological agent, knowledge about the immune response of fish against this organism is limited . At present, there is only one paper in the literature dealing with this subject . To standardise challenge methods for testing the efficacy of vaccination, lethal dose 50% and infectivity dose 50% were determined for coho salmon (Oncorhynchus kisutch) and rainbow trout (O . mykiss) using intraperitoneal (i.p.) injections of P . salmonis . Experiments using bath challenge methods failed to reproduce the disease using rainbow trout although low levels of infection in their tissues were found . In a field trial, using formalin killed bacterins injected i.p . into pre-smolt coho salmon, the fish were naturally challenged by placing them in sea water where endemic piscirickettsiosis occurred . The results showed that some of the vaccinated fish groups experienced lower cumulative mortality than the non-vaccinated control group (X < 0.05), suggesting an immunoprotective response in these animals . A trial was also conducted with formalin-killed bacterins in rainbow trout using different antigen concentrations with and without booster injections . Fish were challenged by IP injection of P . salmonis . Vaccinated fish showed less mortality than their respective infected control . Unfortunately the challenge was not strong enough because mortality in the infected control fish was low (20%) . Antibody levels measured by radio-immuno-assay increased until day 40 post vaccination . The highest levels of antibody were obtained in the sera of fish vaccinated with concentrated antigen using booster injections. Dev Biol Stand, 1997, 90, 107 - 16 Immunization with bacterial antigens: furunculosis; Ellis AE; Although the nature of the antigens and the immune responses they elicit to achieve immunity to furunculosis are still not well defined, the currently available vaccines comprising A . salmonicida bacterins emulsified in oil adjuvants and delivered by intraperitoneal injection provide remarkably high levels of long-lasting protection . Despite some concern over side-effects, these vaccines have been adopted by most Atlantic salmon farmers over the last four years, transforming a situation where furunculosis outbreaks were becoming catastrophic to one where losses from the disease are negligible . Present evidence indicates that antibody responses to the polysaccharide capsule and iron regulated outer membrane proteins are associated with protection . Furthermore, cell-mediated immune responses involving antigen-induced release of cytokines from lymphocytes and the resultant activation of macrophages with the ability to kill the pathogen are also considered important protective mechanisms . Vaccines comprising whole A . salmonicida cultures grown under iron-restricted conditions and delivered by injection in an oil adjuvant are expected to induce prolonged stimulation of all the above responses . While these vaccines are suitable and effective for administration to salmon smolts there is still a need for mass vaccination by immersion or oral routes for salmonid fry . Effective means of achieving this are still required. Boll Soc Ital Biol Sper, 1997 Jan-Feb, 73(1-2), 31 - 8 An electron microscopical investigation of small round viruses in non-bacterial gastroenteritis; Sigari G et al.; Small round viruses implied in non-bacterial gastroenteritis were observed by electron microscope in stool specimens collected from 1993 to 1996 . The specimens relative to 1981 were re-examined . The identified viruses are astroviruses (n = 6), caliciviruses (n = 7), Norwalk-like viruses (n = 34) and Parvoviruses (n = 6) . Immunoelectron microscopy (IEM) and solid-phase immunoelectron microscopy (SPIEM) were used in order to verify serological differences existing among Norwalk-like viruses from different outbreaks . The results obtained suggest a possible circulation, in Liguria, of two serotypes of antigenically different viruses in the period considered. Ann Med Interne (Paris), 1997, 148(3), 218 - 25 {Prevention of bacterial infections in immunocompromised hosts, excluding HIV infection and mycobacterium infections}; Raguin G; The immunocompromised host is an individual whose defense mechanisms against infectious agents are altered in such a significant way that he is abnormally susceptible to infections agents in general and bacterial "opportunists" in particular . The type of infection and etiologic agents vary with the nature and the severity of the immune defect . The goal of prophylactic treatments is to prevent the occurrence or recurrence of infections, and so, to reduce the infectious morbidity and mortality when the nature of severity of immunosuppression make these complications probable . Beside specific measures, which are detailed in this article, the strict application of the so-called universal precautions, particularly handwashing, remain at the basis of the prevention of bacterial infections in the immunocompromised host. Zentralbl Gynakol, 1997, 119 Suppl 1, 28 - 32 {Multivariate analysis of the significance of vaginal bacterial colonization in the occurrence of a preterm birth with various risk parameters}; Faber R et al.; Using a discriminance analysis we investigated the interactions between parameters of the vaginal flora and subclinical infection regarding preterm birth . The prospective study includes 222 single pregnancies, 114 of them with preterm labour or premature rupture of the membranes (PROM) . The analysis includes information of a vaginal/ cervical smear (total number of pathogenic germs, species and groups of pathogenic germs), vaginal pH, maternal white blood cell count (WBC), C-reactive protein (CRP) and temperature . A normal vaginal flora was found in only 19% . Pregnancies with preterm labour have a higher quantity of pathogenic germs, whereas there is no difference of the germ group distribution . Moreover, pregnancies with preterm labour and 2 or 3 pathogenic germs have a higher rate of preterm birth . The discriminance analysis shows that only the affiliation the risk group with preterm labour and the parameters CRP and WBC have a significant selectivity for consequent preterm birth, but not the parameters containing information of the vaginal flora . The same is valid for the group with preterm labour, where only the parameters PROM and WBC are able to select significantly for preterm birth. Probl Tuberk, 1997, (2), 17 - 8 {Treatment of tuberculosis patients with massive bacterial excretion}; Gavril'ev SS et al.; A new endobronchial treatment has been developed for patients with destructive pulmonary tuberculosis with massive bacterial excretion, complicated by chronic nonspecific endobronchitis . The treatment includes inhalation therapy with antituberculous drugs dissolved in activated silver water . This treatment of 42 patients has shown more than 2-fold increases in the rate of massive bacterial excretion cessation. Membr Cell Biol, 1997, 10(5), 535 - 41 Mixed lipid-protein films of bacterial photosynthetic reaction centres . II . Mixed multilayers on solid supports; Kalabina NA et al.; Mixed lipid-protein multilayers composed of the reaction centre (RC) proteins from the Chloroflexus aurantiacus and Rhodobacter sphaeroides (wild type) photosynthetic bacteria and synthetic lipids were investigated . The optimal conditions for forming thin films on solid plates (approximately 100% transfer) were 30 mN/m surface pressure and transfer of the interfacial monolayers from the buffer/air interface onto the plates by the Langmuir-Schaefer method . The films transferred onto quartz and optical transparent current-conducting plates retained their optical and photoelectric properties . The preferential orientation of the protein of the interfacial surface depended on the type of lipid used . In RC-acryloylphosphatidylethanolamine films, the H subunit of the RC from Rhodobacter sphaeroides was oriented toward the water phase, in contrast to RC-diacetylenic acid films, in which the H-subunit was oriented toward the air phase . It is shown that RC can change their orientation in a monolayer, even to the opposite one, depending on the type of lipid matrix. Rev Assoc Med Bras, 1997 Jan-Mar, 43(1), 15 - 20 {Bacterial aerosol generated by mechanical ventilators: comparative study}; Dias MD et al.; Mechanical ventilators generate aerosol which may be bacterially colonized . PURPOSE: To determine the environmental contamination generated by ventilators with two different humidification techniques . METHODS: The study was done comparing the generation of bacterial colonized aerosol by the expiratory valve of mechanical respirators with conventional water nebulization or with hygroscopic condensator as the humidifier source during 15 minutes of observation . RESULTS: The aerosol got positive cultures in 32.2% of the conventional system and in 5% of the condensator system (p = 0.0340) . CONCLUSION: We concluded that the humidification by the hygroscopic condensator may be an efficient way to reduce environmental bacteria contamination. Biochem Cell Biol, 1997, 75(1), 45 - 53 <