| ferrioxamine-mediated iron(iii) utilization by salmonella enterica. | utilization of ferrioxamines as sole sources of iron distinguishes salmonella enterica serotypes typhimurium and enteritidis from a number of related species, including escherichia coli. ferrioxamine supplements have therefore been used in preenrichment and selection media to increase the bacterial growth rate while selectivity is maintained. we characterized the determinants involved in utilization of ferrioxamines b, e, and g by s. enterica serotype typhimurium by performing siderophore cross- ... | 1999 | 10103258 |
| characterization of saccharomyces cerevisiae cbs 7764 isolated from rainbow trout intestine. | a wild-type saccharomyces cerevisiae, strain cbs 7764, isolated from the intestine of rainbow trout, was analyzed with respect to general growth parameters and global protein expression. characterization of this strain was of interest since previous data show non-typical s. cerevisiae cell surface properties and because data suggest a probiotic potential of cbs 7764. the heat production rate (dq/dt), monitored by microcalorimetry, showed that the typical growth phases resulting from diauxic grow ... | 1999 | 10188286 |
| autoregulation of lactose uptake through the lacy permease by enzyme iiaglc of the pts in escherichia coli k-12. | bacterial growth on one or more carbon sources requires careful control of the uptake and metabolism of these carbon sources. in escherichia coli, the phosphorylation state of enzyme iiaglc of the phosphoenolpyruvate:carbohydrate phosphotransferase system (pts) is involved in this control in two ways. the unphosphorylated form of iiaglc causes 'inducer exclusion', the inhibition of uptake of a number of non-pts carbon sources, including lactose uptake by the lactose permease. the phosphorylated ... | 1999 | 10209753 |
| [effect of antibiotics and antibody on phagocytic bactericidal activity of polymorphonuclear neutrophils of bordetella pertussis]. | the phagocytic bactericidal activity of the polymononucler neutrophils (pmns) that were collected from healthy volunteer with and without antibody against bordetella pertussis was investigated. furthermore, these activity against b. pertussis under observing penicillins or macrolides antibiotics was investigated. although no efficacy to b. pertussis strain by the pmns in serum without antibody, but the viable cells of b. pertussis decreased to 1/1,000 1 hr after incubation and was not detected a ... | 1999 | 10222670 |
| analysis of strain variation of r1 repeated structure in varicella-zoster virus dna by polymerase chain reaction. | the tandem direct reiteration r1 in the varicella-zoster virus genome consists of two elements: units composed of 18 bp and those having 15 bp, both of whose numbers and types of combination patterns vary among strains. the variations of the r1 structure were examined in order to differentiate between the wild strains and a varicella vaccine (oka) strain by the polymerase chain reaction using two primer sets. the results showed that the 31 wild strains were classified into nine patterns: the r1 ... | 1999 | 10223550 |
| an efficient gene replacement and deletion system for an extreme thermophile, thermus thermophilus. | a thermus thermophilus host strain of which the leub gene was totally deleted was constructed from a delta pyre strain by a two step method. first, the leub gene was replaced with the pyre gene. second, the inserted pyre gene was deleted by using 5-fluoroorotic acid. a plasmid vector with the leub marker was constructed and the plasmid complemented the leub deficiency of the host. when the leub gene from escherichia coli and its derivative encoding a stabilized enzyme were expressed with the hos ... | 1999 | 10227171 |
| nitric oxide-induced potentiation of the killing of burkholderia cepacia by reactive oxygen species: implications for cystic fibrosis. | burkholderia (formerly pseudomonas) cepacia has emerged as an important pulmonary pathogen in cystic fibrosis, and survives within the lung despite a vigorous neutrophil-dominated immune response. nitric oxide (no) contributes to the antimicrobial activity of reactive oxygen species in the normal lung, but recent evidence suggests that inducible no synthase is not expressed in the airway epithelial cells of cystic fibrosis (cf) patients. this may explain the failure of the neutrophil response to ... | 1999 | 10229538 |
| duplicate genes for fe-containing superoxide dismutase in streptomyces coelicolor a3(2). | streptomyces coelicolor müller contains two types of superoxide dismutase (sod) containing ni (encoded by sodn) or fe (encoded by sodf). unlike a single species of fe-containing sod in müller strain, multiple forms of fesods were detected in s. coelicolor a3(2) strain by activity staining and western blot analysis. genomic southern hybridization suggested the presence of at least two copies of the sodf-like gene in a3(2). two different genes for fesod (sodf1 and sodf2) were isolated from the pha ... | 1999 | 10231572 |
| impact of thioesterase activity on tylosin biosynthesis in streptomyces fradiae. | the polyketide lactone, tylactone, is produced in streptomyces fradiae by the tylg complex of five multifunctional proteins. as with other type i polyketide synthases, the enzyme catalysing the final elongation step (tylgv) possesses an integral thioesterase domain that is believed to be responsible for chain termination and ring closure to form tylactone, which is then glycosylated to yield tylosin. in common with other macrolide producers, s. fradiae also possesses an additional thioesterase g ... | 1999 | 10322123 |
| the use of non-immune plasma powder in the prophylaxis of neonatal escherichia coli diarrhoea in calves. | the protective use of plasma powder from cattle and swine against experimentally induced neonatal e. coli diarrhoea in colostrum-deprived calves was examined. diarrhoea was induced with a strain expressing f5+ fimbriae and a strain expressing f17+ fimbriae. in all groups supplemented with bovine plasma powder, diarrhoea and fever were less severe than in the control groups. for the groups infected with the f5+ e. coli strain, a reduction in excretion of the challenge strain by 2-4 orders of magn ... | 1999 | 10337234 |
| hyperproduction of tryptophan by corynebacterium glutamicum with the modified pentose phosphate pathway. | a classically derived tryptophan-producing corynebacterium glutamicum strain was recently significantly improved both by plasmid-mediated amplification of the genes for the rate-limiting enzymes in the terminal pathways and by construction of a plasmid stabilization system so that it produced more tryptophan. this engineered strain, ky9218 carrying pkw9901, produced 50 g of tryptophan per liter from sucrose after 80 h in fed-batch cultivation without antibiotic pressure. analysis of carbon balan ... | 1999 | 10347033 |
| a phylogenetic analysis by multilocus enzyme electrophoresis and multiprimer random amplified polymorphic dna fingerprinting of the leishmania genome project friedlin reference strain. | we have assessed the phylogenetic status of the leishmania genome project friedlin reference strain by mlee and multiprimer rapd including a set of 9 stocks representative of the main leishmania species and of the whole genetic diversity of the leishmania genus. to our knowledge, the detailed genetic characterization of the friedlin strain has never been published before. as previously recorded (tibayrenc et al. 1993), mlee and rapd data gave congruent phylogenetic results. the friedlin referenc ... | 1999 | 10353190 |
| molecular typing of escherichia coli o157:h7 (h-) isolates from cattle in japan. | a total of 77 escherichia coli o157:h7 (h-) isolates from cattle in japan were investigated by molecular biological methods. most of these isolates (43 isolates) possessed the stx-2 gene, but not stx1. fifteen bacteriophage types and 50 pulsed-field gel electrophoresis (pfge) profiles were observed. one isolate was indistinguishable from the human outbreak strain by these methods. this indicates that cattle must be considered as a possible source of human e. coli o157:h7 infection in japan. | 1999 | 10355801 |
| the heterogeneity in the immune response and efficiency of viral dissemination in brain infected with herpes simplex virus type 1 through peripheral or central route. | using immunohistochemistry on adjacent brain sections, we studied the correlation between the dissemination of the virus, the inflammatory responses and the expression of major histocompatibility complex (mhc) proteins in rat brain infected with herpes simplex virus (hsv-1) f strain by either corneal scarification or intracerebral injection. our results showed that the mortality of the corneally infected rats was much higher than that of the intracerebrally infected rats, due to a more extensive ... | 1999 | 10378385 |
| escherichia coli mutants lacking all possible combinations of eight penicillin binding proteins: viability, characteristics, and implications for peptidoglycan synthesis. | the penicillin binding proteins (pbps) synthesize and remodel peptidoglycan, the structural component of the bacterial cell wall. much is known about the biochemistry of these proteins, but little is known about their biological roles. to better understand the contributions these proteins make to the physiology of escherichia coli, we constructed 192 mutants from which eight pbp genes were deleted in every possible combination. the genes encoding pbps 1a, 1b, 4, 5, 6, and 7, ampc, and amph were ... | 1999 | 10383966 |
| a disrupted homologue of the human cln3 or juvenile neuronal ceroid lipofuscinosis gene in saccharomyces cerevisiae: a model to study batten disease. | 1. in order to investigate the biological function of the human cln3 gene that is defective in batten disease, we created a yeast strain by pcr-targeted disruption of the yeast gene (yhc3), which is a homologue of the human cln3 gene. 2. the phenotypic characterization revealed that the yhc3 delta mutants are more sensitive to combined heat and alkaline stress than the wild-type strains as determined by inhibition of cell proliferation. 3. this suggests that the yhc3 delta mutant is a good model ... | 1999 | 10384264 |
| serum antibody responses to helicobacter pylori and the caga marker in patients with mucosa-associated lymphoid tissue lymphoma. | the lymphoma of the mucosa-associated lymphoid tissue (malt) of the stomach has been linked to helicobacter pylori infection, but the mechanisms involved in b-cell proliferation remain elusive. in a search for putative h. pylori-specific monoclonal immunoglobulin production, an h. pylori strain was isolated from 10 patients with malt lymphoma and used to detect the specific serum antibody response to the homologous strain by immunoblotting. moreover, the antigenicity of the different strains was ... | 1999 | 10391879 |
| identification of clostridium botulinum with api 20 a, rapid id 32 a and rapid ana ii. | three commercially available test systems for the identification of anaerobic bacteria were evaluated for the identification of 18 proteolytic group i and 69 non-proteolytic group ii clostridium botulinum, four clostridium sporogenes and 18 non-toxigenic group ii c. botulinum-like strains. all proteolytic c. botulinum strains were misidentified by the rapid id 32 a and rapid ana ii, while 14 strains and all c. sporogenes strains were identified as c. botulinum or c. sporogenes by the api 20 a. r ... | 1999 | 10397310 |
| in-vitro resistance to azoles associated with mitochondrial dna deficiency in candida glabrata. | a commercially available disk diffusion procedure was used in a large-scale study to evaluate the susceptibility of a wide range of candida isolates to polyenes and azoles. with almost all isolates of c. glabrata resistant colonies were present within the inhibition zones for the azole compounds fluconazole, ketoconazole and miconazole, and less frequently for isoconazole, econazole and clotrimazole. ten randomly selected isolates were cloned by limiting dilution and the susceptibility of the re ... | 1999 | 10403417 |
| experimental investigations on the b and t cell immune response in primary alveolar echinococcosis. | susceptibility/resistance of the intermediate host to alveolar echinococcosis (ae) seems to be based on hitherto unknown immunological mechanisms, possibly involving the activation of different cd4+ t cell immune responses (th1/th2). mice of two strains previously characterized as 'susceptible' (c57bl/6 j) and 'resistant' (c57bl/10 j) to secondary ae were orally infected with eggs of echinococcus multilocularis and the course of infection was analysed by macroscopical, pathohistological and immu ... | 1999 | 10417675 |
| identification of two mannoproteins released from cell walls of a saccharomyces cerevisiae mnn1 mnn9 double mutant by reducing agents. | in this report, we present the identification of the main polypeptides that are extracted from purified cell walls of a saccharomyces cerevisiae mnn1 mnn9 strain by reducing agents. treatment of the purified cell walls of this strain with beta-mercaptoethanol releases several mannoproteins, of which three, with apparent sizes of 120, 45, and 40 kda, are the most abundant. analysis of the amino-terminal sequences revealed that the 120-kda mannoprotein is bar1p, the protease involved in the so-cal ... | 1999 | 10438739 |
| detection of intrastrain antigenic variation of bacteroides fragilis surface polysaccharides by monoclonal antibody labelling. | bacteroides fragilis is a constituent of the normal resident microbiota of the human intestine and is the gram-negative obligately anaerobic bacterium most frequently isolated from clinical infection. surface polysaccharides are implicated as potential virulence determinants. we present evidence of within strain immunochemical variation of surface polysaccharides in populations that are noncapsulate by light microscopy as determined by monoclonal antibody labelling. expression of individual epit ... | 1999 | 10456873 |
| virulence of salmonella enterica serotype enteritidis aflagellate and afimbriate mutants in a day-old chick model. | certain fimbriae and the flagellae of salmonella enterica serovar typhimurium have been shown to contribute to attachment and invasion of gut epithelium in the murine typhoid infection model and to contribute to pathogenesis in the chick. however, little is known of the role these organelles play in enteritidis poultry infections and, to study this, day-old chicks were dosed orally in separate experiments with defined multiply afimbriate and/or aflagellate mutant strains of enteritidis. the colo ... | 1999 | 10459641 |
| introduction of a nora promoter region mutation into the chromosome of a fluoroquinolone-susceptible strain of staphylococcus aureus using plasmid integration. | it has been postulated that a mutation 11 bp 3' to the -10 motif of the nora promoter is involved in the increased expression of the gene observed in some strains of staphylococcus aureus exhibiting efflux-related fluoroquinolone resistance. introduction of this mutation into the chromosome of a fluoroquinolone-susceptible strain by plasmid integration resulted in the minimum inhibitory concentrations of nora substrates being increased, fluoroquinolone uptake being reduced, and nora expression b ... | 1999 | 10471568 |
| in vitro inhibition of drug-resistant and drug-sensitive strains of mycobacterium tuberculosis by ethnobotanically selected south african plants. | twenty south african medicinal plants used to treat pulmonary diseases were screened for activity against drug-resistant and drug-sensitive strains of mycobacterium tuberculosis. a preliminary screening of acetone and water plant extracts against a drug-sensitive strain of mycobacterium tuberculosis, h37rv, was done by the agar plate method. fourteen of the 20 acetone extracts showed inhibitory activity at a concentration of 0.5 mg/ml against this strain. acetone as well as water extracts of cry ... | 1999 | 10473184 |
| mechanism of l-methionine overproduction by escherichia coli: the replacement of ser-54 by asn in the metj protein causes the derepression of l-methionine biosynthetic enzymes. | we derived l-methionine-analogue-resistant mutants from escherichia coli jm109 strain by mutagenesis with n-methyl-n'-nitro-n-nitrosoguanidine and selected the potent l-methionine-overproducing strains by microbioassay using lactic acid bacteria. one of the mutants, strain tn1, produced approximately 910 mg l-methionine/l following the addition of 0.1% yeast extract to fundamental medium containing glucose and ammonium sulfate. the l-methionine biosynthetic enzymes, cystathionine gamma-synthase ... | 1999 | 10499257 |
| assessment of immune response to meningococcal disease: comparison of a whole-blood assay and the serum bactericidal assay. | a whole-blood assay (wba), which assesses the complete bactericidal activity of blood, was compared with the serum bactericidal assay (sba), which measures antibody and complement mediated cell lysis. twenty children infected with serogroup b strains and 25 infected with serogroup c strains were studied 8-12 weeks after disease, and 29 healthy children were used as controls. the infecting strain (convalescent children only) and two reference strains, mc58 (b:15:p1.7, 16) and nctc 8554 (c:nt:p1.5 ... | 1999 | 10502461 |
| directed evolution to bypass cyclin requirements for the cdc28p cyclin-dependent kinase. | to identify cyclin-dependent kinase mutants with relaxed cyclin requirements, cdc28 alleles were selected that could rescue a yeast strain expressing as its only cln g1 cyclin a mutant cln2p (k129a,e183a) that is defective for cdc28p binding. rescue of this strain by mutant cdc28 was dependent upon the mutant cln2-kaea, but additional mutagenesis and dna shuffling yielded multiply mutant cdc28-byc alleles (bypass of clns) that could support highly efficient cell cycle initiation in the complete ... | 1999 | 10518216 |
| infectibility of endovascular stents following antibiotic prophylaxis or after arterial wall incorporation. | case reports of endovascular stent infection have been accumulating in the last several years. we sought to determine if prophylactic antibiotics would prevent stent/artery complex infections in a swine model if given before a bacterial challenge at the time of stent placement and 4 weeks following deployment. we also investigated whether arterial wall incorporation protected the stent against infection without antibiotic prophylaxis. | 1999 | 10527443 |
| differences in the immune response against ruminant chlamydial strains in a murine model. | cba/j mice were used in the present study to establish differences between the immune response to three chlamydial strains: ab7 (chlamydia psittaci wild-type strain), 1b (c. psittaci vaccinal strain) and ib1 (c. pecorum). the evolution of chlamydial infection was evaluated in each strain by studying the clinical signs, the number of bacteria isolated from the spleen and the pathology of the liver. three aspects of the immune response were then studied: the characterization of the infiltrate of l ... | 1999 | 10543384 |
| characterization of the pathway-specific positive transcriptional regulator for actinorhodin biosynthesis in streptomyces coelicolor a3(2) as a dna-binding protein. | the actii-orf4 protein has been characterized as a dna-binding protein that positively regulates the transcription of the actinorhodin biosynthetic genes. the target regions for the actii-orf4 protein were located within the act cluster. these regions, at high copy number, generate a nonproducer strain by in vivo titration of the regulator. the mutant phenotype could be made to revert with extra copies of the wild-type actii-orf4 gene but not with the actii-orf4-177 mutant. his-tagged recombinan ... | 1999 | 10559161 |
| calcyclin gene expression is increased by mechanical strain in fibroblasts and lung. | mechanical tension extending throughout the structural elements of the lung is a potential stimulus for cell proliferation and gene expression. pulmonary fibroblasts located in the interstitial space of the capillary wall throughout the lung parenchyma and within the large vessels and airways are uniquely situated to sense changes in mechanical force. therefore, we used the polymerase chain reaction-based method of differential display analysis to screen for altered gene expression in fetal huma ... | 1999 | 10572072 |
| transmission of the 263k scrapie strain by the dental route. | apart from a few cases of iatrogenic and familial human transmissible spongiform encephalopathies (tses) or prion diseases, the cause of creutzfeldt-jakob disease (cjd) remains unknown. in this paper we investigated the possibility that dental procedures may represent a potential route of infection. this was assessed by using the experimental model of scrapie in hamster. in the first part of this study we found that after intraperitoneal inoculation, oral tissues commonly involved in dental proc ... | 1999 | 10580068 |
| roselipins, inhibitors of diacylglycerol acyltransferase, produced by gliocladium roseum kf-1040. | gliocladium roseum kf-1040, a marine isolate, was found to produce a series of new inhibitors of diacylglycerol acyltransferase (dgat). four active compounds, designated roselipins 1a, 1b, 2a and 2b, were isolated from the fermentation broth of the producing strain by solvent extraction, ods column chromatography and preparative hplc. the highest production of roselipins was observed when cultured in the medium containing natural sea water. roselipins inhibit dgat activity with ic50 values of 15 ... | 1999 | 10580381 |
| identification of genes in a kg- phenotype of lactococcus garvieae, a fish pathogenic bacterium, whose proteins react with antikg- rabbit serum. | five different clones (sa1b05, sa1b10, sa2f01, sa8a11 and sa9h10) were isolated from the gene library of the lactococcus garvieae sa8201 (kg-) strain by immunological screening using rabbit serum against l. garvieae (kg-) phenotype cells. a western blot analysis indicated that the molecular sizes of immunologically detected proteins of sa1b05, sa1b10, sa2f01, sa8a11 and sa9h10, which were fused with lacz protein, were 25, 30, 28, 26 and 13 kda, respectively. the amino acid sequences of the immun ... | 1999 | 10588913 |
| characterization of the glucosyltransferases that assemble the side chains of the indian leishmania donovani lipophosphoglycan. | the life cycle of leishmania parasites within its sand fly vector involves the development of extracellular promastigotes from a noninfective, "procyclic" stage into an infective, "metacyclic" stage that is adapted for transmission in the fly and survival in the mammalian host. lipophosphoglycan (lpg), the predominant surface glycoconjugate in both procyclic and metacyclic stages, is a critical virulence determinant. lpg is a multidomain molecule; the structural polymorphisms among species lie i ... | 1999 | 10600177 |
| phenochalasins, inhibitors of lipid droplet formation in mouse macrophages, produced by phomopsis sp. ft-0211. | phomopsis sp. ft-0211, a soil isolate, was found to produce inhibitors of lipid droplet formation in mouse peritoneal macrophages. structurally related new compounds designated phenochalasins a and b were isolated from the fermentation broth of the producing strain by solvent extraction, ods column chromatography and preparative hplc. phenochalasin a caused a dose-dependent reduction in the number and size of lipid droplets in macrophages without any cytotoxic effect at least up to 20 microm. on ... | 1999 | 10604753 |
| construction of mini-tn10luxabcam/ptac-ats and its use for developing a bacteriophage that transduces bioluminescence to escherichia coli o157:h7. | mini-tn10luxabcam/ptac-ats was constructed in order to develop a luciferase-transducing bacteriophage for detecting escherichia coli o157:h7. the transposon was designed to deliver a 3.6-kb insertion that confers n-decanal-dependent bioluminescence and resistance to chloramphenicol and was constructed using mini-tn10cam/ptac-ats in the plasmid pnk2884 and luxab from vibrio harveyi. phiv10, a temperate bacteriophage infecting common phage types of escherichia coli o157:h7, was mutagenized as a pr ... | 2000 | 10620680 |
| the introduction of strain and its effects on the structure and stability of t4 lysozyme. | in order to try to better understand the role played by strain in the structure and stability of a protein a series of "small-to-large" mutations was made within the core of t4 lysozyme. three different alanine residues, one involved in backbone contacts, one in side-chain contacts, and the third adjacent to a small cavity, were each replaced with subsets of the larger residues, val, leu, ile, met, phe and trp. as expected, the protein is progressively destabilized as the size of the introduced ... | 2000 | 10623513 |
| biology of attenuated modified vaccinia virus ankara recombinant vector in mice: virus fate and activation of b- and t-cell immune responses in comparison with the western reserve strain and advantages as a vaccine. | the modified vaccinia virus ankara (mva) strain is a candidate vector for vaccination against pathogens and tumors, due to safety concerns and the proven ability of recombinants based on this vector to trigger protection against pathogens in animals. in this study we addressed the fate of the mva vector in balb/c mice after intraperitoneal inoculation in comparison with that of the replication-competent western reserve (wr) strain by measuring levels of expression of the reporter luciferase gene ... | 2000 | 10623755 |
| analysis of capsid formation of human polyomavirus jc (tokyo-1 strain) by a eukaryotic expression system: splicing of late rnas, translation and nuclear transport of major capsid protein vp1, and capsid assembly. | human polyomavirus jc (jcv) can encode the three capsid proteins vp1, vp2, and vp3, downstream of the agnoprotein in the late region. jcv virions are identified in the nucleus of infected cells. in this study, we have elucidated unique features of jcv capsid formation by using a eukaryotic expression system. structures of jcv polycistronic late rnas (m1 to m4 and possibly m5 and m6) generated by alternative splicing were determined. vp1 would be synthesized from m2 rna, and vp2 and vp3 would be ... | 2000 | 10644357 |
| inactivation of six genes from chromosomes vii and xiv of saccharomyces cerevisiae and basic phenotypic analysis of the mutant strains. | within the frame of the eurofan project, aimed at the functional analysis of the novel orfs revealed by the systematic sequencing of the saccharomyces cerevisiae genome, we have inactivated six orfs encoding putative proteins with unknown function in the two s. cerevisiae strains fy1679 and w303-1b. five orfs are located on chromosome vii (ygr250c, ygr251w, ygr260w, ygr262c, ygr263c) and one on chromosome xiv (ynl234w). the genes have been inactivated in the fy1679 strain by a strategy that make ... | 2000 | 10649454 |
| [cloning and expression of leptospiral protective antigen gene ompl1 in bcg]. | this study was intended to produce a new living vaccine against leptospirosis using bcg as vector. leptospiral outer envelop antigen gene ompl1 was amplified from the genome of pathogenic leptopira serova lai 017 by pcr, and cloned in e. coli-bcg shuttle plasmid py6002. recombinant plasmids were isolated by dot blotting with digoxigeninlabeled ompl1 gene. after transforming the recombinant plasmids in bcg (shanghai strain) by electroporation, the genomic dna of all 21 transformants were prepared ... | 1998 | 10683969 |
| identification and characterization of glycoprotein h of mdv-1 ga strain. | a 2439 bp open reading frame (orf) was identified from the dna sequence of bamhi-f and -k2 fragments of marek's disease virus of serotype 1 (mdv-1) ga strain, which predicts an 813 amino acid polypeptide. this peptide is homologous to hsv-1 gh, and has typical glycoprotein features. there are nine potential n-linked glycosylation sites within the extracellular domain. a fragment of the gh orf was cloned into pgex vector in frame with glutathione s-transferase (gst) to produce a gst-gh fusion pro ... | 1999 | 10696437 |
| correlates of immune protection induced by live, attenuated, cold-adapted, trivalent, intranasal influenza virus vaccine. | the authors conducted a 2-year, multicenter, double-blind, placebo-controlled efficacy field trial of live, attenuated, cold-adapted, trivalent influenza vaccine administered by nasal spray to children 15-71 months old. overall, vaccine was 92% efficacious at preventing culture-confirmed infection by influenza a/h3n2 and influenza b. because influenza a/h1n1 did not cause disease during the years in which this study was conducted, the authors sought to determine vaccine efficacy and correlates o ... | 2000 | 10720541 |
| staphylococcus aureus protein a recognizes platelet gc1qr/p33: a novel mechanism for staphylococcal interactions with platelets. | the adhesion of staphylococcus aureus to platelets is a major determinant of virulence in the pathogenesis of endocarditis. molecular mechanisms mediating s. aureus interactions with platelets, however, are incompletely understood. the present study describes the interaction between s. aureus protein a and gc1qr/p33, a multifunctional, ubiquitously distributed cellular protein, initially described as a binding site for the globular heads of c1q. suspensions of fixed s. aureus or purified protein ... | 2000 | 10722602 |
| effect of physiological mechanical perturbations on intact human myocardial repolarization. | the objective of this study was to investigate the relationship between acute decreases in right ventricular volume during valsalva strain (with resultant changes in autonomic neural tone) and measures of local endocardial repolarization time independent of heart rate and autonomic neural tone. | 2000 | 10728350 |
| genetic relationships of infectious bronchitis virus isolates from mississippi broilers. | a 582-base pair segment located in the nucleocapsid protein terminal part of the s1 gene of 26 arkansas (ark)-type infectious bronchitis virus (ibv) isolates from mississippi broilers was amplified and sequenced. reverse transcription-polymerase chain reaction and cycle sequencing techniques were used to elucidate the genetic and deduced amino acid relationships among the isolates. analysis suggested that the nucleotide and amino acid sequences of the isolates were highly conserved, with greater ... | 2000 | 10737646 |
| comparison of soccer shin guards in preventing tibia fracture. | the goal of this study was to evaluate the effectiveness of a number of shin guards in protecting against tibia fracture in soccer players. a secondary purpose was to determine the relationship between the material and structural differences in shin guard design and the protection provided. twenty-three commercially available shin guards were tested on a model leg containing a synthetic tibia that had been calibrated against human cadaver specimens. each guard was categorized into one of four ma ... | 2000 | 10751000 |
| the role of tandem is dimers in is911 transposition. | using a combined in vivo and in vitro approach, we demonstrated that the transposition products generated by is911 from a dimeric donor plasmid are different from those generated from a plasmid monomer. when carried by a monomeric plasmid donor, free is911 transposon circles are generated by intra-is recombination in which one is end undergoes attack by the other. these represent transposition intermediates that undergo integration using the abutted left (irl) and right (irr) ends of the element ... | 2000 | 10760133 |
| actinomycin production persists in a strain of streptomyces antibioticus lacking phenoxazinone synthase. | truncated fragments of the phenoxazinone synthase gene, phsa, were prepared by the pcr. the resulting fragments were cloned into conjugative plasmid pkc1132 and transferred to streptomyces antibioticus by conjugation from escherichia coli. two of the resulting constructs were integrated into the s. antibioticus chromosome by homologous recombination, and each of the resulting strains, designated 3720/pjse173 and 3720/pjse174, contained a disrupted phsa gene. strain 3720/pjse173 grew poorly, and ... | 2000 | 10770769 |
| expansion of epitope cross-reactivity by anti-idiotype modulation of the primary humoral response. | the primary humoral response produces antigen-specific antibodies so to clear the initial infection, and generates a population of corresponding memory cells to prevent infection by future encounters with the same pathogen. the continuous genetic modification of a pathogen's exterior, however, is one mechanism used to evade the immune defenses of its host. here we describe a novel means, involving anti-idiotypic antibodies, by which the host can counteract such pathogen genetic alterations by mo ... | 2000 | 10781835 |
| characterization and analysis of a new gene involved in glucose starvation response in enterococcus faecalis. | the genome sequence of enterococcus faecalis, led us to discover that gls24, encoding a general stress protein, seems to be in the second last position of a putative six-gene operon structure. interestingly, another gene named orf4 located just upstream from gls24 shows strong identity (72%) with this last. to determine the role of the orf4 gene in e. faecalis, we have constructed a mutant strain by homologous recombination. phenotypic analysis of these cells, reveals that orf4 is probably invol ... | 2000 | 10791725 |
| identification, cloning, and initial characterization of rot, a locus encoding a regulator of virulence factor expression in staphylococcus aureus. | a chromosomal insertion of transposon tn917 partially restores the expression of protease and alpha-toxin activities to pm466, a genetically defined agr-null derivative of the wild-type staphylococcus aureus strain rn6390. in co-transduction experiments, transposon-encoded erythromycin resistance and a protease- and alpha-toxin-positive phenotype are transferred at high frequency from mutant strains to agr-null strains of s. aureus. southern analysis of chromosomal dna and sequence analysis of d ... | 2000 | 10809700 |
| intercellular communication in helicobacter pylori: luxs is essential for the production of an extracellular signaling molecule. | individual bacteria of numerous species can communicate and coordinate their actions via the production, release, and detection of extracellular signaling molecules. in this study, we used the vibrio harveyi luminescence bioassay to determine whether helicobacter pylori produces such a factor. cell-free conditioned media from h. pylori strains 60190 and 26695 each induced >100-fold-greater luminescence in v. harveyi than did sterile culture medium. the h. pylori signaling molecule had a molecula ... | 2000 | 10816463 |
| absence of shedding of two b. abortus strains in goats after vaccination with live vaccines. | the objective of this study was to determine if b. abortus rough mutant strains rb51 and rfbk are eliminated in goat milk. thirty milk goats were divided into two groups. group i was inoculated with 4x10(10) cfu/ml of b.abortus rb51 strain and group ii with 1x10(9) cfu/ml of b. abortus rfbk strain by subcutaneous route in the right axilary region. milk samples were taken aseptically on a daily basis for the first 30 days and weekly for the second and third months. the samples were inoculated on ... | 2000 | 10825605 |
| characterization of n2o-producing xanthomonas-like isolates from biofilters as stenotrophomonas nitritireducens sp. nov., luteimonas mephitis gen. nov., sp. nov. and pseudoxanthomonas broegbernensis gen. nov., sp. nov. | a group of yellow-pigmented isolates from ammonia-supplied biofilters showed an unusual denitrification reaction. all strains reduced nitrite but not nitrate without production of nitrogen (n2). the only product found was nitrous oxide (n2o). the strains were divided into two clusters and one separate strain by their fatty acid profiles, which were similar to the fatty acid profiles of the genera xanthomonas and stenotrophomonas. analyses of the 165 rdna sequences showed that these clusters and ... | 2000 | 10826814 |
| an improved integration replacement/disruption method for mutagenesis of yeast essential genes. | we improved the integration replacement/disruption method (shortle, d., novic, p., and botstein, d. proc. natl. acad. sci. usa 81: 4889-4893, 1984) for isolating mutants in any of essential genes of the yeast saccharomyces cerevisiae by integrating mutagenized dna into the wild type gene of interest. we adopted this method to isolate temperature-sensitive mutants of the mpc1 gene encoding the yll031c orf. to facilitate integration of the mutagenic plasmid at a site near the 5' end of the orf, a ... | 2000 | 10846619 |
| enhanced alkaline protease production in addition to alpha-amylase via constructing a bacillus subtilis strain. | bacillus subtilis bios11 strain was previously isolated and identified. this strain naturally produces a high level of alpha-amylase. the multicopy (ps1) plasmid that carries the complete alkaline protease apra gene was introduced to this host strain by transformation. the newly constructed strain was found to express the apra gene and produces a high level of alkaline protease. the level of alpha-amylase production was not affected compared with the parent strain. the ps1 plasmid in the new hos ... | 2000 | 10849799 |
| [the genetic control of the f1-specific components of the capsular antigen in yersinia pestis]. | the preparation of y. pestis capsular antigen f1, isolated from y. pestis fra-positive strain by baker's method, has been shown to have a composition and contain three components: protein, glycoprotein and a lipid-containing component. each of them equally reacts with antibodies to f1 and diagnostic preparations based on these antibodies. the synthesis of protein and glycoprotein is temperature-dependent and controlled by pyt (caf). the synthesis of glycoprotein is constitutive and determined by ... | 1999 | 10852029 |
| isolation of bartonella henselae from a serologically negative cat in bloemfontein, south africa. | sera collected from apparently healthy 6-12-month-old cats (n = 31) presented to the society for the prevention of cruelty to animals veterinary clinic in bloemfontein for neutering were tested for antibodies reactive to bartonella henselae (houston-1 strain) by indirect fluorescent antibody testing. whole blood collected from the cats was used in isolation experiments and subsequent identification of bartonella species was based on comparison of the nucleotide base sequence of polymerase chain ... | 1999 | 10855838 |
| recovery of pathogenic measles virus from cloned cdna. | reverse genetics technology so far established for measles virus (mev) is based on the edmonston strain, which was isolated several decades ago, has been passaged in nonlymphoid cell lines, and is no longer pathogenic in monkey models. on the other hand, mevs isolated and passaged in the epstein-barr virus-transformed marmoset b-lymphoblastoid cell line b95a would retain their original pathogenicity (f. kobune et al., j. virol. 64:700-705, 1990). here we have developed mev reverse genetics syste ... | 2000 | 10864679 |
| [lps mutants of sinorhizobium meliloti and their nodulation competitiveness]. | four tn5-transposon lps mutants of sinorhizobium meliloti (tb9, tb29, ts22 and ts32) have been studied. each of four mutants has been established to contain a single insertion of tn5-transposon in its genome. all mutations are located on a chromosome. nodulation competitiveness (nc) of mutants towards the parent strain of s. meliloti cxm1-188 was investigated by resistant method using coinoculation of mutant and parent strain in the ratio 1:1. it was shown that nc was only 19-31% and 8-10%, for ... | 2000 | 10872284 |
| [selection of high avermectins producing strain and identification of avermectin b1]. | three types of colony, powdery gray, white and bald, were isolated from streptomyces avermitilis atcc31272. among them, only the powdery grey one produces avermectins. sa-76 strain was selected from the powdery grey strain by mutation with high energy electric flow, and its avermectins titer attainde 100 micrograms/ml in shaking flask. avermectin b1 was extracted and purified from the mycelia of sa-76, and identified by uv, ir, 1h-nmr, 13c-nmr and mass spectra. after sa-76 strain was treated twi ... | 2000 | 10883272 |
| aerobic degradation of tetrachloroethylene by toluene-o-xylene monooxygenase of pseudomonas stutzeri ox1. | tetrachloroethylene (pce) is thought to have no natural source, so it is one of the most difficult contaminants to degrade biologically. this common groundwater pollutant was thought completely nonbiodegradable in the presence of oxygen. here we report that the wastewater bacterium pseudomonas stutzeri ox1 degrades aerobically 0. 56 micromol of 2.0 micromol pce in 21 h (vmax approximately 2.5 nmol min(-1) mg(-1) protein and km approximately 34 microm). these results were corroborated by the gene ... | 2000 | 10888848 |
| dimethylsulfone as a growth substrate for novel methylotrophic species of hyphomicrobium and arthrobacter. | dimethylsulfone is a major product of the chemical oxidation in the atmosphere of the principal biogenic sulfur gas, dimethylsulfide, but no studies have been reported on the mechanisms for its microbiological degradation. three novel strains of bacteria have been isolated from enrichment cultures provided with dimethylsulfone as the only carbon and energy substrate. these are novel facultatively methylotrophic species of hyphonmicrobium and arthobacter, capable of growth on a range of one-carbo ... | 2000 | 10896224 |
| analysis of rdxa and involvement of additional genes encoding nad(p)h flavin oxidoreductase (frxa) and ferredoxin-like protein (fdxb) in metronidazole resistance of helicobacter pylori. | metronidazole (mtz) is a critical ingredient of modern multidrug therapies for helicobacter pylori infection. mtz resistance reduces the effectiveness of these combinations. although null mutations in a rdxa gene that encodes oxygen-insensitive nad(p)h nitroreductase was reported in mtz-resistant h. pylori, an intact rdxa gene has also been reported in mtz-resistant h. pylori, suggesting that additional mtz resistance mechanisms exist in h. pylori. we explored the nature of mtz resistance among ... | 2000 | 10898687 |
| the complexity of protective immunity against liver-stage malaria. | sterile protective immunity against challenge with plasmodium spp. sporozoites can be induced in multiple model systems and humans by immunization with radiation-attenuated plasmodium spp. sporozoites. the infected hepatocyte has been established as the primary target of this protection, but the underlying mechanisms have not been completely defined. abs, cd8+ t cells, cd4+ t cells, cytokines (including ifn-gamma and il-12), and no have all been implicated as critical effectors. here, we have in ... | 2000 | 10903750 |
| regulation of expression of the yiaklmnopqrs operon for carbohydrate utilization in escherichia coli: involvement of the main transcriptional factors. | the yiaklmnopqrs (yiak-s) gene cluster of escherichia coli is believed to be involved in the utilization of a hitherto unknown carbohydrate which generates the intermediate l-xylulose. transcription of yiak-s as a single message from the unique promoter found upstream of yiak is proven in this study. the 5' end has been located at 60 bp upstream from the atg. expression of the yiak-s operon is controlled in the wild-type strain by a repressor encoded by yiaj. no inducer molecule of the yiak-s op ... | 2000 | 10913096 |
| quantitative determination of the biodegradable polymer poly(beta-hydroxybutyrate) in a recombinant escherichia coli strain by use of mid-infrared spectroscopy and multivariative statistics. | fourier transform infrared (ftir) spectroscopy in combination with the partial least squares (pls) multivariative statistical technique was used for quantitative analysis of the poly(beta-hydroxybutyrate) (phb) contents of bacterial cells. a total of 237 replicate spectra from 34 samples were obtained together with gas chromatography-determined reference phb contents. using the pls regression, we were able to relate the infrared spectra to the reference phb contents, and the correlation coeffici ... | 2000 | 10919800 |
| [the properties of the cellular surface of yersinia pestis strain ev and its achromogenic variants]. | the comparative study of the properties of the surface of vaccine strain y. pestis ev and its achromogenic variants (av) differing from the initial strain by decreased immunogenicity and by the morphology of colonies, has been made. the achromogenicity of y. pestis colonies has been shown to correlate with the loss of the outer membrane protein with a molecular weight 22 kd. the synthesis of this protein is determined by chromosomal genes. av have been found to have different sensitivity to bact ... | 2000 | 10925864 |
| biochemical characterization of recombinant subunits of type 2a protein phosphatase overexpressed in pichia pastoris. | methylotrophic yeast pichia pastoris was used for a medium-scale expression of structural (pr65/a) and catalytic (pp2ac) subunits of human type 2a protein phosphatase (pp2a). constructs encoding these subunits, which were designed to introduce eight histidines at their n-termini, were introduced into the km71 pichia strain by homologous recombination. recombinant proteins overproduced after methanol induction were purified from cell-free extracts by anion-exchange chromatography on deae-sepharos ... | 2000 | 10931206 |
| [molecular characterization of rotavirus in the city of santafé de bogotá, colombia. determination of the electrophenotypes and typing of a strain by rt-pcr]. | 131 diarrheic samples obtained from children taken to the emergency room of the misericordia hospital in santafé de bogotá were cultivated for rotavirus. these virus were found to be etiological agents for the diarrhea in 42 (32%) of the patients. in order to characterize electrophoretically the rotavirus they were cultured in cell line ma-104, total rna was extracted and subjected to electrophoresis in sds-page and then the retrotranscription polymerase chain reaction. eight different electroph ... | 1999 | 10932761 |
| variation in response among individuals to antigenic sites on the ha protein of human influenza virus may be responsible for the emergence of drift strains in the human population. | eight convalescent human sera obtained from patients aged 3 to 14 years old, who were infected with influenza a(h3n2) virus during the 1990/1991 influenza season, were characterized by a binding assay with chimeric hemagglutinin (ha) proteins between influenza virus a/aichi/2/68 and a/kamata/14/91(h3n2) strains. these sera did not recognize the ha protein of the a/aichi/2/68 strain but recognized that of the a/kamata/14/91 strain. the binding assay revealed that these sera recognized only the ha ... | 2000 | 10936103 |
| therapeutic trial in experimental tegumentary leishmaniasis caused by leishmania (leishmania) amazonensis. a comparative study between mefloquine and aminosidine. | one hundred and eighty-two male inbred c57/bl/6 mice were infected with 3 x 10(6) leishmania (leishmania) amazonensis promastigotes of the mhom/br/ph8 strain by means of a subcutaneous injection in the right ear. the animals were separated in three groups: 1) oral mefloquine hydrochloride treatment (16 mg/kg/day/10 days), 2) intramuscular aminosidine (paromomycin) treatment (20 mg/kg/20 days) and 3) control. twenty-six mice of each treated group were sacrificed, one at the end of treatment (nine ... | 2000 | 10936952 |
| development of hyperfimbriated strains of vibrio cholerae o1. | the vibrio cholerae o1 and o139 fimbrillin genes (fima or msha) were amplified by polymerase chain reaction and cloned into an escherichia coli pcr vector. these clones were sequenced. the fima sequences were found to be identical between v cholerae o1 and o139. one of the plasmids was digested with ecor i and inserted into the ecor i site of pgex-3x. the plasmid pvpp thus obtained was transferred into strains of wild-type v cholerae o1 bgd17 (classical in biotype) and its fimbriated strain by e ... | 2000 | 10941926 |
| an outbreak of enterovirus 71 infection in taiwan, 1998. ii. laboratory diagnosis and genetic analysis. | an epidemic of enterovirus 71 (ev71) occurred in taiwan from april to december of 1998, with two peaks, one in june and the other in october. many enteroviruses were isolated in our laboratory from 258 cases during this outbreak. approximately half of the enteroviruses isolated were ev71 and one fifth were coxsackievirus a16. | 2000 | 10942089 |
| comparative nucleotide sequence analyses of the entire genomes of b95a cell-isolated and vero cell-isolated measles viruses from the same patient. | experimental infection of monkeys with the ic-b strain of measles virus (mv), which was isolated in marmoset b lymphoblastoid b95a cells from an acute measles patient, caused clinical signs typical for measles, while infection by the ic-v strain isolated in african green monkey kidney vero cells from the same patient did not cause any clinical signs in infected monkeys. the ic-b strain replicated only in b95a cells, whereas the ic-v strain replicated in both b95a and vero cells (3,6). to clarify ... | 2000 | 10949953 |
| comparative analyses of secondary gene products of 3-deoxy-d-manno-oct-2-ulosonic acid transferases from chlamydiaceae in escherichia coli k-12. | the waaa gene encoding the essential, lipopolysaccharide (lps)-specific 3-deoxy-dmanno-oct-2-ulosonic acid (kdo) transferase was inactivated in the chromosome of a heptosyltransferase i and ii deficient escherichia coli k-12 strain by insertion of gene expression cassettes encoding the waaa genes of chlamydia trachomatis, chlamydophila pneumoniae or chlamydophila psittaci. the three chlamydial kdo transferases were able to complement the knockout mutation without changing the growth or multiplic ... | 2000 | 10951204 |
| decontamination of a mycoplasma-infected chlamydia pneumoniae strain by pulmonary passage in scid mice. | we describe a procedure to eliminate contaminating mycoplasma from chlamydia pneumoniae (c. pneumoniae) cultures by pulmonary passage in severe combined immunodeficiency mice (scid). four weeks after experimental infection only c. pneumoniae could be cultured from the lungs of the infected animals while mycoplasma could not be detected any longer, as shown by pcr, culture and transmission electron microscopy (tem). | 2000 | 10959732 |
| analysis of 16s rrna and 51-kilodalton antigen gene and transmission in mice of ehrlichia risticii in virgulate trematodes from elimia livescens snails in ohio. | operculate snails (the family pleuroceridae: elimia livescens) were collected between june and october 1998 from a river in central ohio where repeated cases of potomac horse fever (phf) have occurred. of collected snails, consistently 50 to 80% carried a combination of cercariae and sporocysts of digenetic virgulate trematodes. the trematodes obtained from each snail were pooled and tested for ehrlichia risticii, the agent of phf, by nested pcr using primers specific to the 16s rrna gene. out o ... | 2000 | 10970382 |
| myocardial strain by doppler echocardiography. validation of a new method to quantify regional myocardial function. | myocardial strain is a measure of regional deformation, and by definition, negative strain means shortening and positive strain, elongation. this study investigates whether myocardial strain can be measured by doppler echocardiography as the time integral of regional velocity gradients, using sonomicrometry as reference method. | 2000 | 10973846 |
| concerted evolution of duplicate fla genes in campylobacter. | campylobacters have two similar copies (flaa and flab) of their flagellin gene. it has been hypothesized that the two copies can serve for antigenic phase variation. analysis of polymorphisms within aligned multiple dna sequences of the campylobacter flagellin genes revealed high pairwise homoplasy indexes between flab/flab pairs that were not observed between any flaa/flaa pairings or flaa/flab pairings. thus it seems there are constraints on the sequence of flab that distinguish it from flaa. ... | 2000 | 10974116 |
| use of genetically engineered salmonella typhimurium oy1002/1a2 strain coexpressing human cytochrome p450 1a2 and nadph-cytochrome p450 reductase and bacterial o-acetyltransferase in sos/umu assay. | the major pathway of bioactivation of procarcinogenic heterocyclic aromatic amines (hcas) is cytochrome p450 1a2 (cyp1a2)-catalyzed n-hydroxylation and subsequent esterification by o-acetyltransferase (o-at). we have previously reported that an umu tester strain, salmonella typhimurium oy1001/1a2, endogenously coexpressing human cyp1a2 and nadph-p450 reductase (reductase), is able to detect the genotoxicity of some aromatic amines [aryal et al., 1999, mutat res 442:113-120]. to further enhance t ... | 2000 | 11013410 |
| [search for staphylococcus aureus heterogeneously resistant to vancomycin (hetero-vrsa) in mrsa strains isolated from clinical samples during 1990s]. | hetero-vrsa was studied in 978 mrsa strains isolated from clinical samples during 1991 to 1998. although no vrsa was detected, 23 strains (2.4%) were identified as hetero-vrsa by the vancomycin-resistance using mu3 agar plate. the frequency of hetero-vrsa was not increased in the course of time. mic of the hetero-vrsa to vancomycin and teicoplanin was 1-2 micrograms/ml and 0.5-12 micrograms/ml, respectively. all of the hetero-vrsa strains were confirmed as a heterogeneous strain by a population ... | 2000 | 11019513 |
| interaction of the rabies virus p protein with the lc8 dynein light chain. | the rabies virus p protein is involved in viral transcription and replication but its precise function is not clear. we investigated the role of p (cvs strain) by searching for cellular partners by using a two-hybrid screening of a pc12 cdna library. we isolated a cdna encoding a 10-kda dynein light chain (lc8). lc8 is a component of cytoplasmic dynein involved in the minus end-directed movement of organelles along microtubules. we confirmed that this molecule interacts with p by coimmunoprecipi ... | 2000 | 11024151 |
| yeast krr1p physically and functionally interacts with a novel essential kri1p, and both proteins are required for 40s ribosome biogenesis in the nucleolus. | using a two-hybrid screening with tom1, a putative ubiquitin-ligase gene of saccharomyces cerevisiae, we isolated krr1, a homologue of human hrb2 (for human immunodeficiency virus type 1 rev-binding protein 2). to characterize the gene function, we constructed temperature-sensitive krr1 mutants and isolated two multicopy suppressors. one suppressor is rps14a, encoding a 40s ribosomal protein. the c-terminal-truncated rps14p, which was reported to have diminished binding activity to 18s rrna, fai ... | 2000 | 11027267 |
| v gamma 1+ t cells suppress and v gamma 4+ t cells promote susceptibility to coxsackievirus b3-induced myocarditis in mice. | coxsackievirus b3 infections of c57bl/6 mice, which express the mhc class ii ia but not ie ag, results in virus replication in the heart but minimal myocarditis. in contrast, bl.tg.ealpha mice, which are c57bl/6 mice transgenically induced to express ie ag, develop significant myocarditis upon coxsackievirus b3 infection. despite this difference in inflammatory damage, cardiac virus titers are similar between c57bl/6 and bl.tg.ealpha mice. removing gammadelta t cells from either strain by geneti ... | 2000 | 11035049 |
| [lipopolysaccharides of shigella sonnei]. | immunobiological properties of native lipopolysaccharides (lps) from virulent and avirulent strains of shigella sonnei bacteria (lps-v and lps-a, respectively) were studied. in avirulent bacteria, lps-v induced immunosuppressive activity specific of the virulent strain. lps of the avirulent strain, whereas lps-a lacked this property. native lps-v with immunosuppressive activity were isolated from the virulent strain by and immune affinity method. treatment of lps-v with phenol or tca abolished i ... | 2000 | 11042887 |
| comparative sequence analysis identified mutations outside the nsp4 cytotoxic domain of tissue culture-adapted atcc-wa strain of human rotavirus and a novel inter-species variable domain in its c-terminus. | complete nucleotide sequence of the tissue culture-adapted atcc-wa strain of human rotavirus nsp4 was determined. sequence analysis detected two alternate forms of the gene with a nucleotide difference at position 331 (a or g) in the coding sequence (nsp4-a or nsp4-g) leading to a change from neutral glutamine97 in nsp4-a to a positively charged arginine97 in nsp4-g originating from the same atcc-wa preparation. in addition to this, both forms of atcc-wa nsp4 revealed three mutations at nucleoti ... | 2000 | 11043941 |
| strain distribution in plated and unplated sheep tibia an in vivo experiment. | after plate osteosynthesis changes in bone biology and bone mechanics are observed in the plated bone segment. compromise of the vascular supply in the plate bed leads to a remodelling process and to a temporary porosity in the bone cortex underneath the plate. in addition, the plate takes over some of the physiological loading of the bone, which in turn alters the normal strain distribution of the cortical bone tissue. the aim of the present study is to determine the tissue deformation of the s ... | 2000 | 11052379 |
| variability in plant-microbe interaction between lupinus lines and bradyrhizobium strains. | even though lupin (lupinus albus l.) is known to potentially fix 150-200 kg/ha nitrogen for the use of a succeeding crop, precise information about lupinxbradyrhizobium strain interaction under the climatic conditions prevalent in the mid-atlantic region of the united states is unknown. we conducted two greenhouse experiments with the objective of characterizing this symbiotic relationship and to evaluate potential interaction between bradyrhizobium strains and lupin lines. in the first experime ... | 2000 | 11074278 |
| structural and topological differences between a glycopeptide-intermediate clinical strain and glycopeptide-susceptible strains of staphylococcus aureus revealed by atomic force microscopy. | novel cell surface topography was revealed on cocci from a glycopeptide-intermediate staphylococcus aureus (gisa) clinical strain by using atomic force microscopy. the gisa isolate and its revertant had two parallel circumferential surface rings. one equatorial surface ring was observed in control strains. in vancomycin-susceptible strains, additional rings were formed in the presence of vancomycin. ring depth measurements also revealed striking differences between the gisa strain and susceptibl ... | 2000 | 11083659 |
| isolation of a new insertion element of yersinia intermedia closely related to remnants of mobile genetic elements present on yersinia plasmids harboring the yop virulon. | a new insertion element present in two alleles, designated is1635.1 and is1635.2, was identified on a plasmid of a yersinia intermedia strain by hybridization with the yersinia enterocolitica pyv virulence plasmid. is1635.1 and is1635.2 are 861 bp long, carry imperfect inverted terminal repeats and possess a single open reading frame encoding a putative transposase of the is6 family. a truncated is1635 element is present immediately downstream of element is1635.2. the capacity of the is1635 elem ... | 2000 | 11094276 |
| the isolation and characterization in yeast of a gene for arabidopsis s-adenosylmethionine:phospho-ethanolamine n-methyltransferase. | saccharomyces cerevisiae opi3 mutant strains do not have the phospholipid n-methyltransferase that catalyzes the two terminal methylations in the phosphatidylcholine (pc) biosynthetic pathway. this results in a build up of the intermediate phosphatidylmonomethylethanolamine, causing a temperature-sensitive growth phenotype. an arabidopsis cdna library was used to isolate three overlapping plasmids that complemented the temperature-sensitive phenotype. phospholipid analysis showed that the presen ... | 2000 | 11115895 |
| candidate osmosensors from candida utilis and kluyveromyces lactis: structural and functional homology to the sho1p putative osmosensor from saccharomyces cerevisiae. | in saccharomyces cerevisiae, increases in external osmolarity evoke osmostress-induced signalling via the hog map kinase pathway. one of the upstream components of this signal transduction route is the putative osmosensor, sho1p. with the aim to elucidate the molecular basis of osmosensing in budding yeast, we have cloned sho1 homologues from candida utilis and kluyveromyces lactis which allowed determination of conserved domains of sho1p. results obtained from sequence comparisons, confirmed th ... | 2000 | 11118628 |
| mycobacterial growth indicator tube versus the proportion method on löwenstein-jensen medium for antibiotic susceptibility testing of mycobacterium tuberculosis. | the mycobacterial growth indicator tube, a reliable system for detection of mycobacterial growth, was compared with the reference proportion method on löwenstein-jensen medium for antibiotic susceptibility testing of mycobacterium tuberculosis. a total of 62 clinical strains and four reference strains of mycobacterium tuberculosis were tested for susceptibility to streptomycin, isoniazid, rifampicin and ethambutol. of these, 36 were susceptible to all four antibiotics and 30 were resistant to at ... | 2000 | 11205631 |
| strengths and limitations of molecular subtyping in a community outbreak of legionnaires' disease. | an epidemiological and microbiological investigation of a cluster of eight cases of legionnaires' disease in los angeles county in november 1997 yielded conflicting results. the epidemiological part of the investigation implicated one of several mobile cooling towers used by a film studio in the centre of the outbreak area. however, water sampled from these cooling towers contained l. pneumophila serogroup 1 of another subtype than the strain that was recovered from case-patients in the outbreak ... | 2000 | 11218211 |
| meaa, a putative coenzyme b12-dependent mutase, provides methylmalonyl coenzyme a for monensin biosynthesis in streptomyces cinnamonensis. | the ratio of the major monensin analogs produced by streptomyces cinnamonensis is dependent upon the relative levels of the biosynthetic precursors methylmalonyl-coenzyme a (coa) (monensin a and monensin b) and ethylmalonyl-coa (monensin a). the meaa gene of this organism was cloned and sequenced and was shown to encode a putative 74-kda protein with significant amino acid sequence identity to methylmalonyl-coa mutase (mcm) (40%) and isobutyryl-coa mutase (icm) large subunit (36%) and small subu ... | 2001 | 11222607 |
| the estrous cycle affects pseudorabies virus (prv) infection of the cns. | previous work had suggested that mucosal immunity may be affected by the stage of the estrous cycle. here, susceptibility to a neurotropic virus infection at different stages of the estrous cycle was assessed in a rodent model after direct injection of the virus into visceral organs. in the first two experiments, female sprague-dawley rats were infected with pseudorabies virus (prv, bartha's k-strain) by injection into either the cervix or the kidney after monitoring their estrous cycle. after e ... | 2001 | 11223009 |