| characterization of the dtdp-rhamnose biosynthetic genes encoded in the rfb locus of shigella flexneri. | the nucleotide sequence of the proximal half of the rfb region of shigella flexneri has been determined, and the genes encoding enzymes involved in the biosynthesis of dtdp-rhamnose have been identified. these genes show strong homology to the rfb genes encoding dtdp-rhamnose biosynthesis in salmonella enterica serovar typhimurium (strain lt2) and s. enterica serovar anatum (strain m32) (jiang et al., 1991; wang et al., 1992). an open reading frame upstream of rfbb was also identified which enco ... | 1994 | 8170390 |
| molecular mechanisms of cell and tissue invasion by shigella flexneri. | | 1993 | 8173793 |
| unipolar localization and atpase activity of icsa, a shigella flexneri protein involved in intracellular movement. | | 1993 | 8173795 |
| the ipab gene of shigella flexneri and macrophage-programmed cell death. | | 1993 | 8173796 |
| infection, diarrhea, and dysentery caused by shigella species and campylobacter jejuni among guatemalan rural children. | to examine the factors that may influence the outcome of infections by shigella spp. and campylobacter jejuni we followed for 24 consecutive months 321 rural guatemala children 0 to 35 months old. home visits were made to determine child morbidity patterns with emphasis on diarrhea and dysentery. fecal samples for microbiologic studies were obtained from the participants when they were ill and during healthy periods. shigella spp. were isolated from 9.8 and 4.0% of ill and healthy children, resp ... | 1994 | 8177630 |
| non-steroidal anti-inflammatory drug and endotoxin induced uveitis. | suprofen eye drop was instilled into one eye of 10 pigmented rabbits and then anterior uveitis was induced by intraperitoneal injection of endotoxin of shigella flexneri serotype 1a to evaluate the effects of non-steroidal anti-inflammatory drug on endotoxin induced uveitis. the pupillary diameters were measured, and aqueous cell and flare gradings were recorded in 20 eyes of 10 rabbits for one week at an interval of 12 hours for the first 24 hours and then every 24 hours for a week. a differenc ... | 1993 | 8189632 |
| differential scanning calorimetry investigations on lps and free lipids a of the bacterial cell wall. | differential scanning calorimetry (dsc) was used to investigate the thermal stability and behaviour of the lipopolysaccharides (lps) of the outer membrane of gram-negative bacteria and their lipid portion. dsc curves of lps show thermal features between 200 and 129 degrees c (depolymerization) and between -13 and -36 degrees c (cooling phase transition). both effects were related to the relative strength of the linkage types in the o-chain structure and to their capacity for intermolecular hydro ... | 1993 | 8190999 |
| [vaccination against the enterobacteriaceae responsible for enteric infections]. | development of vaccines against enterobacterial species responsible for enteric infections sounds like an unrealistic project. on the other hand, based on our growing understanding of the pathogenesis of infections caused by the major species (i.e. salmonella typhi, shigella flexneri and shigella dysenteriae 1, enterotoxigenic escherichia coli) and on our better characterization of the immunological parameters of mucosal protection, it is likely that a limited number of vaccines controlling dise ... | 1993 | 8193944 |
| ipab mediates macrophage apoptosis induced by shigella flexneri. | shigella flexneri kills macrophages through apoptosis, involving the induction of host cell dna fragmentation and characteristic morphological changes. shigella can only cause damage if it escapes from the phagolysosome into the cytoplasm. the s. flexneri cytotoxic genes have been localized to the ipa operon of shigella's virulence plasmid. ipab, c and d deletion mutants are not invasive and therefore not cytotoxic. in order to distinguish genes involved in the escape from the phagolysosome as d ... | 1994 | 8196540 |
| [the efficacy of quercetin and tocopherol acetate in treating patients with flexner's dysentery]. | quercetin and tocopherol were given to 134 patients with flexner's dysentery intramuscularly for 7 days; 154 patients received routine treatment. it was found that quercetin and tocopherol acetate enhanced normalization of clinical indices and restoration of the immune homeostasis. the above drugs are recommended for the complex treatment of dysentery. | 1993 | 8209460 |
| [vaccination against the enterobacteria responsible for enteric infections]. | development of vaccines against enterobacterial species responsible for enteric infections sounds like an unrealistic project. on the other hand, based on our growing understanding of the pathogenesis of infections caused by the major species (i.e. salmonella typhi, shigella flexneri and shigella dysenteriae 1, enterotoxigenic escherichia coli) and on our better characterization of the immunological parameters of mucosal protection, it is likely that a limited number of vaccines controlling dise ... | 1994 | 8210205 |
| microinjection of hep-2 cells with coxsackie b1 virus rna enhances invasiveness of shigella flexneri only after prestimulation with uv-inactivated virus. | coxsackie b1 virus induces increased susceptibility to invasion by shigella flexneri when hep-2 cells are inoculated with the complete virus. when rna from the same virus was microinjected into cells, virus rna was synthesized and new virus particles were formed, but the transfected rna had no effect on bacterial invasiveness. however, when the cells were prestimulated with uv-inactivated virus, the microinjected rna induced an additional enhancement of bacterial invasiveness. microinjected whol ... | 1993 | 8217113 |
| shigella subversion of the cellular cytoskeleton: a strategy for epithelial colonization. | | 1993 | 8225568 |
| the regulatory vira protein of agrobacterium tumefaciens does not function at elevated temperatures. | previous studies have shown that agrobacterium tumefaciens causes tumors on plants only at temperatures below 32 degrees c, and virulence gene expression is specifically inhibited at temperatures above 32 degrees c. we show here that this effect persists even when the vira and virg loci are expressed under the control of a lac promoter whose activity is temperature independent. this finding suggests that one or more steps in the signal transduction process mediated by the vira and virg proteins ... | 1993 | 8226624 |
| a reversible case of klüver-bucy syndrome in association with shigellosis. | the klüver-bucy syndrome is characterized by psychic blindness or visual agnosia, blunted affect, hypermetamorphosis, hyperorality, bulimia, and sexual behavioral alterations. to date, there have been fewer than 10 reported cases of klüver-bucy syndrome in children, most of them irreversible. we describe here a reversible case of the complete klüver-bucy syndrome in a child suffering from shigella encephalopathy. | 1993 | 8228026 |
| a randomized, double-blind study comparing cefixime and trimethoprim-sulfamethoxazole in the treatment of childhood shigellosis. | we compared the clinical and bacteriologic response of 5-day treatment with cefixime, 8 mg/kg per day, with the response to trimethoprim-sulfamethoxazole (tmp-smx), 10-50 mg/kg per day, the currently recommended therapy. of the assessable children with acute, culture-proven shigellosis, 38 received cefixime and 39 received tmp-smx. pretreatment data on the two study groups were similar. in the first group, all isolates were susceptible to cefixime; in the tmp-smx group, 32 isolates were resistan ... | 1993 | 8229498 |
| comparative efficacy of two- and five-day courses of ceftriaxone for treatment of severe shigellosis in children. | administration of ceftriaxone for 5 days has been shown to be highly efficient in the treatment of severe shigellosis in children. our study, involving 40 children, demonstrated that a 2-day course of ceftriaxone was as beneficial as a 5-day course and constituted effective therapy for children with severe shigellosis. | 1993 | 8229499 |
| induction of tumor necrosis factor and interleukin 6 by outer membrane proteins of shigella in spleen cells and macrophages of mice. | the ability of outer membrane proteins (omp) of shigella flexneri to induce tumor necrosis factor (tnf) and interleukin 6 (il-6) production by spleen cells and macrophages of mice was investigated. treatment of spleen cells with omp resulted in the release of only traces of tnf activity. in contrast, macrophages treated with omp produced moderate levels of tnf. omp was also found to be an inducer of il-6. both spleen cells and macrophages, treated with omp, were found to produce substantial leve ... | 1993 | 8239920 |
| transcription in vitro promoted by the agrobacterium virg protein. | expression of the virulence genes (vir) on the hairy-root-inducing plasmid pria4 is induced by plant signals in agrobacterium cells through a two-component regulatory system, the vira-virg system. we constructed an in vitro transcription system that consisted of the purified virg protein and the agrobacterium rna polymerase holoenzyme. both versions of virg, the non-phosphorylated form and the vira-phosphorylated form, were active but showed different patterns of the ph-dependency for transcript ... | 1993 | 8243632 |
| the chromosomal virulence gene, chve, of agrobacterium tumefaciens is regulated by a lysr family member. | certain plant phenolic compounds and monosaccharides induce the transcription of virulence (vir) genes of agrobacterium tumefaciens through the vira-virg two-component regulatory system. the product of the chromosomal virulence gene chve is homologous to galactose-binding protein of escherichia coli and is required for vir gene induction by sugars. adjacent to, but divergent in transcription from, chve is an open reading frame, now termed gbpr (galactose-binding protein regulator), that is homol ... | 1993 | 8253677 |
| hrpi of erwinia amylovora functions in secretion of harpin and is a member of a new protein family. | hrpi, a 78-kda protein, functions in the secretion of harpin, a proteinaceous elicitor of the hypersensitive response from erwinia amylovora. the predicted amino acid sequence of hrpi is remarkably similar to that of lcrd of yersinia species, the first member of a recently described protein family. other proteins of the family are mixa from shigella flexneri, inva from salmonella typhimurium, flha from caulobacter crescentus, hrpi from pseudomonas syringae pv. syringae, hrpo from pseudomonas sol ... | 1993 | 8253684 |
| comparison of conjugates composed of lipopolysaccharide from shigella flexneri type 2a detoxified by two methods and bound to tetanus toxoid. | shigella flexneri type 2a lipopolysaccharide (lps) was detoxified with acetic acid (o-sp) or with hydrazine (dealps). dealps, but not o-sp, retained part of its lipid a. both gave an identical line of precipitation with typing antiserum by double immunodiffusion, and both had low levels of lps activity by the limulus amoebocyte lysate assay. o-sp had an m(r) of approximately 17,000. dealps had two components of m(r)s approximately 30,00 (major and approximately 10,000 (minor). adipic acid hydraz ... | 1994 | 8262629 |
| [analgesic effect and gastro-intestinal motility inhibitory action of 3-hydroxy-4-methoxy-acetophenone from cynanchum paniculatum (bunge) kitagawa]. | 3-hydroxy-4-methoxy-acetophenone (hma) isolated from cynanchum paniculatum was found to have analgesic effect and inhibitory action on the gastro-intestinal motility. the effect and action were equivalent to that of paeonol, hma displayed a very low degree of antibacterial activity against escherichia coli and shigella flexneri. | 1993 | 8274216 |
| evaluation of butorphanol tartrate and buprenorphine hydrochloride on the inflammatory reaction of the sereny test. | invasion of the ocular epithelia of guinea pigs by virulent shigella organisms, eliciting keratoconjunctivitis, is the basis of the sereny test (st). this test has been used to ascertain the virulence of shigella strains and more recently to screen candidate shigella vaccines for efficacy. this test undoubtedly causes pain in test animals; however, recommendation for use of local analgesics/anesthetics has not been accepted because of concern that these topical agents may affect the ability of t ... | 1993 | 8277729 |
| molecular characterization, nucleotide sequence, and expression of the flio, flip, fliq, and flir genes of escherichia coli. | the flil operon of escherichia coli contains seven genes that are involved in the biosynthesis and functioning of the flagellar organelle. dna sequences for the first three genes of this operon have been reported previously. a 2.2-kb psti restriction fragment was shown to complement known mutant alleles of the flio, flip, fliq, and flir genes, the four remaining genes of the flil operon. four open reading frames were identified by dna sequence analysis and correlated to their corresponding genes ... | 1994 | 8282695 |
| serum antibody responses against shigella lipopolysaccharides and invasion plasmid-coded antigens in shigella infected swedish patients. | serum antibody responses to shigella lipopolysaccharide (lps) and invasion plasmid-coded antigens (ipa) were studied in 74 swedish patients with culture verified bacillary dysentery using class-specific enzyme immunoassay (eia). anti-lps responses were found in 80% and 79% serum samples, respectively, from s. flexneri and s. sonnei infected patients and anti-ipa responses in 60% and 43%, respectively. the mean anti-ipa igg antibody titres in s. flexneri infected patients remained high for 4-6 mo ... | 1993 | 8284641 |
| recent trends in the epidemiology of shigella species in israel. | trends in the epidemiology of infections due to shigella species over a period of 6 years (1986-1991) in israel were studied by analysis of the results of 51,300 stool cultures, of which 2,987 yielded shigella species. in a university hospital, the relative prevalence of shigella sonnei in patients with shigellosis increased over the years from 60% in 1986 to 91% in 1991 (r = 0.93; p = .007); concomitantly, the prevalence of shigella flexneri decreased from 29% to only 8% (r = -0.80; p < .05). i ... | 1993 | 8286636 |
| [on the outbreak of shigellosis in tokyo, 1992]. | in 1992, the number of cases of shigellosis in tokyo increased remarkably, and a total of 10 separate outbreaks were confirmed. except for 1 series where the causative strains was shigella flexneri 3a, the other 9 outbreaks were caused by shigella sonnei. of note, 7 outbreaks were familial with less than 5 patients. the remaining 3 outbreaks occurred in a restaurant, a school and the dormitory of an orphanage, in which the organism was detected in 6 to 14 patients. in 4 of the familial outbreaks ... | 1993 | 8294768 |
| bacillus subtilis flagellar proteins flip, fliq, flir and flhb are related to shigella flexneri virulence factors. | the amino acid sequences of the bacillus subtilis flagellar proteins, flip, fliq, flir and flhb, as deduced from their respective nucleotide sequences, were found to share significant homology to the shigella flexneri spa24, spa9, spa29 and spa40 virulence proteins, respectively. these proteins are required for the presentation of surface plasmid antigens. these results further support the growing hypothesis that a superfamily of proteins exists for the biosynthesis of supramolecular structures ... | 1993 | 8299954 |
| mutants of agrobacterium vira that activate vir gene expression in the absence of the inducer acetosyringone. | in the presence of inducer molecules produced by wounded plants, the vira/virg two-component positive regulatory system of agrobacterium tumefaciens initiates transcription of virulence genes required for crown gall tumor formation. exactly how this system enables the bacterium to respond to an environmental signal is not known, but phosphorylation of vira and virg plays a role. to analyze further the function of vira, we chemically mutagenized the vira gene. two mutants that activate vir transc ... | 1994 | 8300595 |
| characterization of a plasmid codifying the synthesis of a beta-lactamase produced by shigella flexneri. | the resistance to beta-lactam antibiotics shown by a strain of shigella flexneri was plasmid-coded. this plasmid, pmam-1, when transferred to escherichia coli k-12 by conjugation, presented the same molecular weight (100 kbp) and conferred the same high level of resistance to ampicillin in the transconjugant as in the wild type strains (mic, 2048-4096). restriction analysis of the plasmid in transconjugants revealed various restrictive sites to some endonucleases (i.e. bam hi, eco ri, pst i, nco ... | 1993 | 8302197 |
| effect of five irreversible inhibitors on beta-lactamase from shigella flexneri ucsf-129. | the effect of five irreversible inhibitors on purified enzyme from shigella flexneri uscf-129 and also in vitro, was investigated. the i50 was 0.091, 0.30, 0.40 and 0.87 microgram/ml for 6 beta-iodopenicillanic, clavulanic, olivanic and 6 beta-bromopenicillanic acids, respectively, and 255 micrograms/ml for sulbactam. the synergic responses of these inhibitors (10 micrograms/ml) were studied with ampicillin and cephradin on s. flexneri. the mic of ampicillin was reduced by 128 times using 6 beta ... | 1993 | 8302198 |
| the binding site of the transcriptional activator virg from agrobacterium comprises both conserved and specific nonconserved sequences. | virulence genes of agrobacterium tumefaciens are transcriptionally activated in response to phenolic compounds and certain sugars. the transcription activator virg specifically binds to fragments containing the conserved vir box sequence present in the promoter region of all vir genes. this study shows that both the vir box as well as specific nonconserved sequences downstream of the vir box are required for virg binding and transcriptional activation. insertion of the identified virg binding si ... | 1994 | 8307169 |
| [molecular genetic studies on virulence-associated chromosomal loci of shigella flexneri 2 a]. | | 1993 | 8309077 |
| homology between the hrpo protein of pseudomonas solanacearum and bacterial proteins implicated in a signal peptide-independent secretion mechanism. | a region of approximately 22 kb of dna defines the large hrp gene cluster of strain gmi1000 of pseudomonas solanacearum. the majority of mutants that map to this region have lost the ability to induce disease symptoms on tomato plants and are no longer able to elicit a hypersensitive reaction (hr) on tobacco, a non-host plant. in this study we present the complementation analysis and nucleotide sequence of a 4772 bp region of this hrp gene cluster. three complete open reading frames (orfs) are p ... | 1993 | 8316211 |
| cloning and sequencing of the glucosyl transferase-encoding gene from converting bacteriophage x (sfx) of shigella flexneri. | shigella flexneri type y strains (-;3,4) are converted to type x (-;7,8) by bacteriophage x (sfx) that causes glucosylation of the o-antigenic polysaccharide chain. the gene (gtr) encoding glucosyl transferase from bacteriophage x has been cloned and sequenced. the protein encoded by gtr consists of 416 amino acids with a m(r) of 47,369. the cloned gtr product was able to convert a s. flexneri strain type y (sfl 124, a live attenuated candidate vaccine strain) to type x. the importance of the hy ... | 1993 | 8335266 |
| immunization of mice with yersinia enterocolitica leads to the induction of antithyrotropin receptor antibodies. | it is well established that autoimmune graves' disease, which is characterized by hyperthyroidism, is mediated by autoantibodies to the thyrotropin receptor (tshr). although what initially triggers this autoantibody response is not known, a number of studies have suggested that yersinia enterocolitica, an enterobacteria, could initiate the immune response against the tshr. in this study, we produced antibodies against purified extracellular domain of human tshr (etshr) and showed that anti-etshr ... | 1993 | 8335920 |
| [characteristics of the shigella flexneri strains isolated from japanese monkeys (macaca fuscata)]. | shigella flexneri was isolated from 11 of 95 japanese monkeys (macaca fuscata) purchased by the animal research center, tokyo medical and dental university, during the period from 1988 through 1990. the serotypes of the isolates were 4a (5 isolates), 2a (4 isolates), 2b (1 isolate), and vary (1 isolate). although some of the strains in the same serotypes were similar, others were different in their antibiotic susceptibility patterns or the plasmid profiles. our results suggested that various typ ... | 1993 | 8336006 |
| morpho-physiologic characteristics of escherichia coli and shigella flexneri 2a carrying the htpr15 gene. | electron microscopic examination of the morphology of normal escherichia coli mc4100 and shigella flexneri cells and their htpr-defective recombinants has shown the presence in the latter of noncrystalline granules after growth at 37 degrees c. the defect of the htpr gene leads to some changes in ultrastructure of bacterial colonies and the intensification of the processes of development and aging of colonies as integral structures. these phenomena are manifested by early formation of intercellu ... | 1993 | 8336285 |
| inactivation of beta-lactamase from shigella flexneri ucsf-129 by brl 42715, a potent inhibitor. | the effect of a powerful inhibitor, brl 42715, on beta-lactamase from shigella flexneri ucsf-129, to overcome the problem of shigellosis and its resistance to ampicillin, was studied. the i50 was determined for brl 42715 [c6-(n1-methyl-1,2,3 triazolylmethylene)penem] as 0.0049 microgram/ml being 20-fold lower than the best inhibitor, 6-beta-iodopenicillanic acid, previously reported. the mic fell from 2,048 to 2 micrograms/ml in the presence of 1 microgram/ml of brl 42715. the synergism of the a ... | 1993 | 8336551 |
| the possible role of shigella in sporadic enteric reactive arthritis. | reactive arthritis (rea) occurs after a urogenital infection usually with chlamydia trachomatis or an enteritis due to yersinia, salmonella, campylobacter or shigella, shigella, except during epidemics, is not considered to be a frequent cause of enteric reactive arthritis. however this might be due to the lack of a reliable antibody test, which makes diagnosis difficult. we compared synovial and peripheral blood lymphocyte proliferation to various bacterial antigens in 19 consecutive patients w ... | 1993 | 8339129 |
| diffuse adherence of enteropathogenic escherichia coli strains--processing of aida-i. | the adherence of pathogenic escherichia coli to the mucosa of the small intestine is an important step in the development of diarrhoea. to study the molecular basis of the diffuse adherence (da) pattern of e. coli strains expressing the classical serotypes of enteropathogenic e. coli (epec), strain 2787 (o126:h27) was investigated. by expression cloning, a plasmid-derived 6.0 kb dna fragment was identified which conferred the da phenotype on recipient k-12 strains. this fragment encoded the 100 ... | 1993 | 8347926 |
| arod deletion attenuates shigella flexneri strain 2457t and makes it a safe and efficacious oral vaccine in monkeys. | the aromatic-dependent live shigella flexneri 2a vaccine strain sfl1070, with a deleted arod gene, had a much reduced intracellular growth in hela cells compared with its parent strain s. flexneri 2457t. s. flexneri sfl1070 gave no adverse effects in eight macaca fascicularis monkeys orally vaccinated with four doses of 1 x 10(11) live bacteria within a 5-week period, whereas s. flexneri 2457t caused dysentery in all eight non-vaccinated monkeys. thus the aromatic dependency rendered s. flexneri ... | 1993 | 8356844 |
| ompc is involved in invasion of epithelial cells by shigella flexneri. | osmoregulation of the shigella flexneri ompc gene and the role of ompc in shigella virulence have been investigated. ompc was highly expressed when bacteria were grown in medium of either low or high osmolarity. this constitutive expression is in contrast with the regulation observed in escherichia coli, in which the expression of ompc is repressed at low osmolarity and induced at high osmolarity. in addition, the shigella ompc gene was barely expressed by a delta ompb (delta ompr and delta envz ... | 1993 | 8359885 |
| synthesis, characterization, and clinical evaluation of conjugate vaccines composed of the o-specific polysaccharides of shigella dysenteriae type 1, shigella flexneri type 2a, and shigella sonnei (plesiomonas shigelloides) bound to bacterial toxoids. | the theoretic basis for developing conjugate vaccines, to induce immunoglobulin g (igg) lipopolysaccharide (lps) antibodies for the prevention of shigellosis, has been described (j. b. robbins, c.-y. chu, and r. schneerson, clin. infect. dis. 15:346-361, 1992). the o-specific polysaccharides (o-sps) of shigella dysenteriae type 1, s. flexneri type 2a, and s. sonnei were covalently bound to carrier proteins. alone, the o-sps were not immunogenic in mice. conjugates of these o-sps, injected into y ... | 1993 | 8359890 |
| characterisation of plesiomonas shigelloides strains that share type-specific antigen with shigella flexneri 6 and common group 1 antigen with shigella flexneri spp. and shigella dysenteriae 1. | three strains of plesiomonas shigelloides isolated from patients with diarrhoea were agglutinated with shigella flexneri 6 antiserum in slide and tube tests. all the strains were also agglutinated with a monoclonal antibody to the common group 1 antigen shared between s. flexneri serotypes and s. dysenteriae type 1. further studies with one strain also showed sharing of antigenicity in an enzyme-linked immunosorbent assay. the results suggest that the strains share type-specific antigen with s. ... | 1993 | 8366520 |
| necrotizing haemorrhagic colitis caused by resistant shigella flexneri. report of a case. | a case of fatal infection with shigella flexneri is reported. the 19-year-old male patient who presented with fulminating haemorrhagic colitis died nine days after the onset of symptoms. the infecting strain of shigella flexneri was resistant to multiple antimicrobial agents, including amoxycillin, co-trimoxazole and chloramphenicol. | 1993 | 8367972 |
| evaluation of alkaline phosphatase-labelled ipah probe for diagnosis of shigella infections. | the presence of many enteropathogens which are not easily detectable by routine stool culture has led to the development of alternative diagnostic methods. one of these techniques, nucleic acid probe hybridization, has been used to identify shigella spp. and enteroinvasive escherichia coli (eiec) in stool specimens through the detection of genetic material encoded by a specific large approximately 200-kbp virulence-related plasmid. in the present study, an alkaline phosphatase-labelled oligonucl ... | 1993 | 8370736 |
| the bacteriophage mu middle operon: essential and nonessential functions. | transcription during the bacteriophage mu lytic cycle occurs in three phases: early, middle, and late. previous dna sequence analysis of the middle operon revealed five potential open reading frames (orfs) with lengths of 39, 42, 72, 120, and 140 amino acids. the distal 140-amino-acid orf encodes c, the activator of late transcription. expression of the middle operon under the control of a t7 promoter and t7 rna polymerase resulted in production of two polypeptides of 15 (orf 120) and 16.5 kda ( ... | 1993 | 8372443 |
| nonpolar mutagenesis of the ipa genes defines ipab, ipac, and ipad as effectors of shigella flexneri entry into epithelial cells. | a 31-kb fragment of the large virulence plasmid of shigella flexneri is necessary for bacterial entry into epithelial cells in vitro. one locus of this fragment encodes the ipaa, -b, -c, and -d proteins, which are the dominant antigens of the humoral immune response during shigellosis. to address the role of the ipa genes, which are clustered in an operon, we constructed a selectable cassette that does not affect transcription of downstream genes and used this cassette to inactivate the ipab, ip ... | 1993 | 8376337 |
| tumor necrosis factor alpha binding to bacteria: evidence for a high-affinity receptor and alteration of bacterial virulence properties. | human and murine receptors for tumor necrosis factor alpha (tnf-alpha) are present on most somatic cells and have been characterized and cloned. in contrast, very little is currently known about whether tnf-alpha can bind to pathogens and whether such binding results in important biological consequences for the infected host. we now report that a number of gram-negative bacteria have receptors for tnf-alpha. using 125i-labeled tnf-alpha, we show that shigella flexneri has 276 receptors for tnf-a ... | 1993 | 8381771 |
| rotavirus-inhibitory activity in serial milk samples from mexican women and rotavirus infections in their children during their first year of life. | a total of 75 children born in rural mexico were followed for diarrheal diseases and rotavirus (rv) excretion during the first year of life. for 18 children, an average of 14 serial breast milk samples were obtained between days 2 and 360 after delivery and were tested for rv-inhibitory activity. of these samples, 70, 62, and 85% showed inhibitory activity against serotype (st) 1 human rv, st4 human rv, and st3 simian rv, respectively; the median titers were 10, 10, and 20, respectively. some 89 ... | 1993 | 8384626 |
| isolation and characterization of a topa mutant of shigella flexneri. | shigella flexneri was shown to possess a homologue of the escherichia coli k-12 topa gene which encodes dna topoisomerase i. the s. flexneri topa gene was replaced by a copy of the e. coli k-12 topa gene which has been insertionally inactivated by transposon tn10. the topoisomer distribution of reporter plasmids showed that the presence of this topa lesion in s. flexneri correlated with an increase in the level of negative dna supercoiling in the mutant, indicating that topoisomerase i is requir ... | 1993 | 8384681 |
| eight genes in region 5 that form an operon are essential for invasion of epithelial cells by shigella flexneri 2a. | the 7-kb region 5 on the large 230-kb plasmid pmysh6000 in shigella flexneri 2a ysh6000 is one of the virulence-associated dna segments required for the invasion of epithelial cells (c. sasakawa, k. kamata, t. sakai, s. makino, m. yamada, n. okada, and m. yoshikawa, j. bacteriol. 170:2480-2484, 1988). to elucidate the functional organization of region 5 and to determine the virulence-associated genes encoded by region 5, we performed insertion and deletion mutagenesis, dna subcloning, and comple ... | 1993 | 8385666 |
| characterization of virulence genes of enteroinvasive escherichia coli by tnphoa mutagenesis: identification of invx, a gene required for entry into hep-2 cells. | while enteroinvasive escherichia coli (eiec) and shigellae are genotypically nearly identical, a difference has been reported in the infective dose to humans: eiec is 10,000-fold less infectious than shigellae. a possible basis for this difference lies in the inherent invasiveness of these bacteria toward epithelial cells. thus, despite the high degree of homology between the invasion plasmids of eiec and shigellae, substantial differences in genetic organization and/or sequence may exist. we ha ... | 1993 | 8393007 |
| cognate gene clusters govern invasion of host epithelial cells by salmonella typhimurium and shigella flexneri. | the enteric pathogens salmonella typhimurium and shigella flexneri differ in most virulence attributes including infectivity, pathology and host range. we have identified a new assemblage of genes responsible for invasion properties of salmonella which is remarkably similar in order, arrangement and sequence to the gene cluster controlling the presentation of surface antigens (spa) on the virulence plasmid of shigella. in salmonella, this chromosomally encoded complex consists of over 12 genes, ... | 1993 | 8404849 |
| shigella flexneri invasion of hela cells induces nf-kappa b dna-binding activity. | although information about the genetic basis and mechanisms of shigella flexneri cellular invasion is accumulating, little is known about changes in cell signaling and their consequences following bacterium-host cell interactions. a general result of signal transduction is alterations in the levels and/or activities of transcription factors. alterations in transcription factor binding activities were observed following challenge with s. flexneri. changes in the dna-binding activities of cellular ... | 1993 | 8406833 |
| prevalence of shigellosis and other enteric pathogens in a zoologic collection of primates. | an epidemiologic study of shigellosis was the preliminary step in the formulation of a plan for the control of devastating infectious diseases in nonhuman primates at the national zoological park. data were collected from primate groups with enzootic shigellosis and included the following species: white-cheeked and siamong gibbons (hylobates concolor and h syndactylies); lion-tailed, celebes, and barbary macaques (macaca silenus, m nigera, and m sylvanus); black and white colobus monkeys (colobu ... | 1993 | 8407446 |
| clearance of shigella flexneri carriers in a zoologic collection of primates. | in 1990, a high prevalence of shigella flexneri was documented in the gibbon population at the national zoological park. the enzootic strain had been determined to be resistant to most antibiotics and had been responsible for animal deaths. prevalence of shigella spp was high in the entire primate population. to address the clinical problem, eradication was attempted by use of enrofloxacin. facilities disinfection comprised a large part of shigella clearance efforts. after the clearance protocol ... | 1993 | 8407447 |
| cytokines in stools of children with inflammatory bowel disease or infective diarrhoea. | to determine the concentrations of interleukin-6 (il-6) and tumour necrosis factor alpha (tnf alpha) in stools from children. | 1993 | 8408704 |
| site of transcriptional activation of virb on the large plasmid of shigella flexneri 2a by virf, a member of the arac family of transcriptional activators. | virb plays a central role in the regulation of virulence of shigella flexneri. it acts as a transcriptional activator and is itself transcriptionally activated by another virulence protein, virf. experiments were performed in order to identify the site upstream of virb at which virf binds in order to activate transcription. progressive 5' deletions of the dna upstream of the transcription start point of virb were constructed by subcloning and bal31 deletion. these deletion derivatives were clone ... | 1993 | 8412620 |
| a pleiotropic reduced virulence (rvi-) mutant of erwinia carotovora subspecies atroseptica is defective in flagella assembly proteins that are conserved in plant and animal bacterial pathogens. | erwinia carotovora subsp. atroseptica was mutagenized and assayed for virulence in planta. those mutants which exhibited reduced virulence (rvi-) were assayed for growth rate, auxotrophy and extracellular enzyme secretion and seven mutants were found to be wild type for all of these phenotypes. when screened for other phenotypes, two were found to be non-motile. one mutant was complemented for motility by a heterologous gene library. a 2.7kb xmaiii-clai complementing fragment was sequenced and t ... | 1993 | 8412685 |
| the absence of a surface protease, ompt, determines the intercellular spreading ability of shigella: the relationship between the ompt and kcpa loci. | a large plasmid-encoded protein, virg, on the bacterial surface is essential for the spreading of shigella by eliciting polar deposition of filamentous actin in the cytoplasm of epithelial cells. virg expression from the large plasmid is diminished greatly when it is introduced into escherichia coli k-12 from shigella. in an attempt to identify factors affecting virg expression, we found that the absence of the ompt gene, encoding outer membrane protease ompt, restored full production of virg pr ... | 1993 | 8412695 |
| yopb and yopd constitute a novel class of yersinia yop proteins. | virulent yersinia species harbor a common plasmid that encodes essential virulence determinants (yersinia outer proteins [yops]), which are regulated by the extracellular stimuli ca2+ and temperature. the v-antigen-encoding operon has been shown to be involved in the ca(2+)-regulated negative pathway. the genetic organization of the v-antigen operon and the sequence of the lcrgvh genes were recently presented. the v-antigen operon was shown to be a polycistronic operon having the gene order lcrg ... | 1993 | 8418066 |
| enteric protein loss during shigellosis. | to determine whether protein-losing enteropathy occurs during shigellosis, we measured concentrations of alpha 1-antitrypsin in sequential stool samples from 110 adults hospitalized with acute dysentery due to shigella infection. mean stool concentrations of alpha 1-antitrypsin on admission were 10.9 micrograms/mg dry weight of stool. stool alpha 1-antitrypsin concentrations were significantly (p < 0.001) lower on the 3rd and 5th study days (4.1 and 2.2 micrograms/mg, respectively) than on admis ... | 1993 | 8420274 |
| detection of shigellae and enteroinvasive escherichia coli by amplification of the invasion plasmid antigen h dna sequence in patients with dysentery. | detection of shigella organisms and enteroinvasive escherichia coli (eiec) by polymerase chain reaction (pcr) was evaluated in 20 patients with dysentery before and in 17 of the 20 after treatment with ciprofloxacin. dna sequences coding for ipah antigen, a multiple copy sequence found on the chromosome, and the invasion plasmid locus (ial) was detected after dna amplification in 13 stools from patients from whom shigellae or eiec were isolated but not in 21 nondysenteric stools containing other ... | 1993 | 8421181 |
| concentrations of interleukin 6 and tumour necrosis factor in serum and stools of children with shigella dysenteriae 1 infection. | serum interleukin 6 (il-6) and tumour necrosis factor (tnf) were measured in children with dysentery during an epidemic caused by shigella dysenteriae 1. il-6 and tnf were also measured in fresh stool filtrates from children with acute gastroenteritis. the median serum il-6 concentration was raised significantly in the children with complications (haemolytic uraemic syndrome, leukemoid reaction, thrombocytopenia, thrombocytosis, and severe colitis lasting more than one week) during the first wee ... | 1993 | 8432472 |
| immune response against lipopolysaccharide and invasion plasmid-coded antigens of shigellae in vietnamese and swedish dysenteric patients. | the peripheral immune responses of adult vietnamese patients infected with shigella dysenteriae 1 and shigella flexneri 1b and 2a and those of s. flexneri-infected swedish patients were studied against various lipopolysaccharide and invasion plasmid-coded antigens (ipa-s) and compared with the titers for the corresponding local healthy populations. both vietnamese and swedish patients reacted with significant (p, < 0.05) titer increases in the immunoglobulin a and g classes against the homologou ... | 1993 | 8432838 |
| rectal histopathology in endemic shigella and salmonella diarrhea. | rectal histopathology was evaluated in 34 cases (2 months-12 yrs old) of endemic "invasive diarrhea" [> 20 wbcs per high-power field on stool microscopy with (rbc positive) or without (rbc negative) associated rbcs] where s. dysenteriae (n = 9), s. flexneri (n = 11), and nontyphoidal salmonella were isolated as the sole identifiable enteropathogens. persistent diarrhea (> 14 days duration) was more common with salmonella infection whereas rbc-positive "invasive diarrhea" was more frequent with s ... | 1993 | 8433237 |
| growth and survival of shigella flexneri in common bangladeshi foods under various conditions of time and temperature. | survival and growth of shigella flexneri were assessed in various foods, including boiled rice, lentil soup, milk, cooked beef, cooked fish, mashed potato, mashed brinjal, and raw cucumber. growth at 25 and 37 degrees c and survival at 5 degrees c were observed by viable counts on macconkey agar. the organism grew well in all tested foods and growth increased from 10(5) to 10(8) to 10(10) cells per ml or g within 6 to 18 h after inoculation at 25 and 37 degrees c. | 1993 | 8434933 |
| mxid, an outer membrane protein necessary for the secretion of the shigella flexneri lpa invasins. | the invasive phenotype of shigella flexneri is conferred by a 220 kb virulence plasmid, pwr100, that encodes both the lpa proteins, which are involved in the entry process, and factors which are required for the export and correct localization of the lpa proteins. we have characterized the mxid gene, whose expression, like that of the ipa operon, is regulated by temperature. after inactivation of mxid, the mutant strain was unable to invade hela cells and to provoke keratoconjunctivitis in guine ... | 1993 | 8437520 |
| safety and immunogenicity of the live oral auxotrophic shigella flexneri sfl124 in adult vietnamese volunteers. | the live, auxotrophic dependent shigella flexneri y vaccine strain sfl124 with a deleted arod gene was tested in 30 healthy adult male vietnamese volunteers. a single dose of 2 x 10(9) live bacteria was given orally to 15 volunteers, whereas 15 received three doses every other day. none of the volunteers reacted with fever or diarrhoea and sfl124 was excreted by all for a mean of 2.8 (single dose) and 2.6 (three doses) days. a total of 27 of 30 (90%) and 26 of 30 (87%) responded with significant ... | 1993 | 8438616 |
| evaluation of shigella vaccine safety and efficacy in an intranasally challenged mouse model. | five shigella vaccine candidates (ecsf2a-1, ecsf2a-2, sfl124, t32-istrati and smd) were tested for safety and efficacy in balb/cj mice using an intranasal challenge model. experiments in this model suggest that (i) the relative attenuation of vaccines can be determined in mice by intranasal inoculation, (ii) all vaccines tested elicited antibacterial mucosal immunity protecting against pulmonary infection with shigella flexneri 2a, (iii) protection was associated with serum iga and/or igg antibo ... | 1993 | 8438617 |
| shigella flexneri 2a and sonnei i vaccine with two attenuating markers: construction, tolerability and immunogenicity in 143 children aged 3-17 years. | the vaccine candidates were constructed through stepwise incorporation of weakly attenuated purine auxotrophy with subsequent rifampicin resistance (rna polymerase) mutation to yield optimal attenuation. these strains showed a maintained invasiveness for conjunctival epithelia. therefore, while not causing keratoconjunctivitis, they were excreted for a short but marked period and provided partial protection in the sereny test. children tolerated the maximum dose of 1-3 x 10(9) colony-forming uni ... | 1993 | 8438618 |
| an arginine residue at the active site of beta-lactamase from shigella flexneri ucsf-129. | the role of a residue of arginine at the active site of beta-lactamase from shigella flexneri ucsf-129 was studied. it is a local pathogenic strain which produces intestinal problems, especially in children. purified enzymes were obtained by affinity chromatography on phenylboronic acid-agarose gels. the enzyme was serine dependent with a molecular weight of 23.6 kd. it was specifically modified with phenylglyoxal (1/830 molar ratio) and incubated for 20 min in the presence of 50 mm sodium phosp ... | 1993 | 8441355 |
| characterization of a virg mutation that confers constitutive virulence gene expression in agrobacterium. | transformation of plants by agrobacterium tumefaciens is mediated by a set of virulence (vir) genes that are specifically induced by plant signal molecules through the vira/virg two-component regulatory system. the plant signal is transmitted from vira to virg by a cascade of phosphorylation reactions followed by the sequence-specific dna binding of the virg protein to the vir gene promoters which then activates their transcription. in this report, we describe a virg mutant which is able to acti ... | 1993 | 8459774 |
| rapid detection of shigella dysenteriae and shigella flexneri in faeces by an immunomagnetic assay with monoclonal antibodies. | a rapid and sensitive method for the detection of shigella dysenteriae type 1 and shigella flexneri serotypes in faeces based on capture of the bacteria with immunomagnetic particles is described. the particles were coated with either of two different monoclonal antibodies specific for the o-antigens of shigella dysenteriae type 1 and shigella flexneri serotypes. captured bacteria were detected by an enzyme immunoassay with o-antigen specific rabbit antiserum. the whole assay required 2 to 3 hou ... | 1993 | 8462557 |
| unipolar localization and atpase activity of icsa, a shigella flexneri protein involved in intracellular movement. | shigella flexneri uses elements of the host cell cytoskeleton to move within cells and from cell to cell. icsa, an s. flexneri protein involved in this movement, was purified and studied in vitro. icsa bound the radiolabelled atp analog 3'(2')-o-(4-benzoyl)benzoyl-atp and hydrolyzed atp. in addition, the surface localization of icsa on both extracellular and intracellular shigellae was unipolar. further, in hela cells infected with shigellae, icsa antiserum labelled the actin tail throughout its ... | 1993 | 8468279 |
| shigellosis due to occupational contact with non-human primates. | a small cluster of dysenteric illness, due to shigella flexneri, was identified among technical assistants of a primate research unit. all of the affected individuals had been in regular contact with a colony of cynomolgus macaque monkeys, one of which was known to have suffered from acute haemorrhagic colitis in the preceding few weeks. four monkeys were found to be excreting s. flexneri bacilli of identical antigen type (1b) to that isolated from the human cases. investigation of working pract ... | 1993 | 8472767 |
| characterization of the shigella flexneri ipgd and ipgf genes, which are located in the proximal part of the mxi locus. | the shigella flexneri invasion process requires the synthesis of the ipa proteins and their secretion by specific factors encoded by the mxi and spa genes, which are clustered upstream from the ipa operon. we report here the characterization of the ipgd, ipge, and ipgf genes, which are located in the 5' end of the mxi locus. analysis of ipgf-phoa fusions endowed with high levels of alkaline phosphatase activity confirmed the functionality of a classical signal sequence detected in the sequence o ... | 1993 | 8478058 |
| directional actin polymerization associated with spotted fever group rickettsia infection of vero cells. | members of the spotted fever group (sfg) of rickettsiae spread rapidly from cell to cell by an unknown mechanism(s). staining of rickettsia rickettsii-infected vero cells with rhodamine phalloidin demonstrated unique actin filaments associated with one pole of intracellular rickettsiae. f-actin tails greater than 70 microns in length were seen extending from rickettsiae. treatment of infected cells with chloramphenicol eliminated rickettsia-associated f-actin tails, suggesting that de novo prote ... | 1993 | 8478082 |
| plants used in guatemala for the treatment of gastrointestinal disorders. 3. confirmation of activity against enterobacteria of 16 plants. | ethnobotanical surveys and literature review identified 408 plants used in guatemala for the treatment of gastrointestinal disorders. the screening of 84 showed that 34 inhibit one or more enterobacteria; 16 of these were selected for further investigation. extracts were obtained with three solvents of different polarity (n-hexane, acetone and alcohol) and the in vitro activity was demonstrated against enteropathogenic escherichia coli, salmonella enteritidis and shigella flexneri. the activity ... | 1993 | 8479202 |
| genetic and biochemical analysis of salmonella typhimurium flii, a flagellar protein related to the catalytic subunit of the f0f1 atpase and to virulence proteins of mammalian and plant pathogens. | flii is a salmonella typhimurium protein that is needed for flagellar assembly and may be involved in a specialized protein export pathway that proceeds without signal peptide cleavage. flii shows extensive sequence similarity to the catalytic beta subunit of the f0f1 atpase (a. p. volger, m. homma, v. m. irikura, and r. m. macnab, j. bacteriol. 173:3564-3572, 1991). it is even more similar to the spa47 protein of shigella flexneri (m. m. venkatesan, j. m. buysse, and e. v. oaks, j. bacteriol. 1 ... | 1993 | 8491729 |
| preliminary crystallographic analysis of a fab specific for the o-antigen of shigella flexneri cell surface lipopolysaccharide with and without bound saccharides. | the fab of a monoclonal anti-carbohydrate antibody, sya/j6 (igg3, kappa, murine), raised against the o-polysaccharide antigen of the cell surface lipopolysaccharide of variant y shigella flexneri, a gram negative bacterium, has been crystallized in the unliganded form and in complex with tri- and pentasaccharide antigens. the three crystal forms belong to the tetragonal space group p4(3)2(1)2, or p4(1)2(1)2, with very similar unit cell dimensions and an asymmetric unit that contains one molecule ... | 1993 | 8496958 |
| immunogenicity and efficacy of oral or intranasal shigella flexneri 2a and shigella sonnei proteosome-lipopolysaccharide vaccines in animal models. | immunity against shigellosis has been shown to correlate with the presence of antibodies specific for shigella lipopolysaccharide (lps). we here propose a new candidate vaccine for shigellosis composed of purified shigella flexneri 2a or shigella sonnei lps hydrophobically complexed with group c type 2b neisseria meningitidis outer membrane protein proteosomes. immunization of mice either orally or intranasally with this complex induced specific homologous anti-lps antibodies in both intestinal ... | 1993 | 8500877 |
| [investigation on distribution and changes of shigella group in fengtai district, beijing from 1979 to 1991]. | a total of 386 strains of shigella were collected and identified by biochemistry and serotyping from 1978 to 1991. results showed that the strains were distributed in 4 groups which included 20 serotypes.s.flexner was predominant, mainly 2a and 3a serotypes, and s.sonnei the next. the ratio of b group to d group was 4.3. | 1993 | 8504452 |
| antibacterial activity of the bryozoan electra bellula (hincks). | the antibacterial activity of the extracts of bryozoan e. bellula (hincks) was tested against ten bacterial strains by antibiotic disc diffusion method. the maximum activity was observed against proteus vulgaris, while klebsiella pneumoniae and shigella flexneri were insensitive to the bryozoan. | 1993 | 8505081 |
| epidemiologic and clinical aspects of shigellosis in american forces deployed to saudi arabia. | i describe nine cases of shigellosis seen at a large navy field hospital in troops deployed to saudi arabia during the gulf war. eight cases were associated with consumption of food at civilian restaurants or civilian-contracted food services. two adults had "pseudomeningitis" syndromes, illustrating that shigellosis in adults may initially be misdiagnosed. all patients responded rapidly to rehydration and oral fluoroquinolone (ciprofloxacin) therapy. five patients received an antimotility agent ... | 1993 | 8506485 |
| [study of genomic polymorphism of shigella flexneri strains, isolated in various geographic regions]. | strains of shigella flexneri isolated from patients in 4 geographic regions of the former ussr have been studied by plasmid analysis and fingerprinting techniques. it has been shown that these methods make possible to differentiate phenotypically identical strains for 9 genotypic patterns (7 different plasmid profiles and 3 specific hybridization patterns). strains of shigella flexneri isolated from each region possess the similar hybridization patterns independent of serovar and plasmid profile ... | 1993 | 8510684 |
| shigella osteomyelitis in a fit young man. | a case of shigella osteomyelitis in an apparently healthy young man is presented. pre-operative and intra-operative swabs taken from the septic focus grew shigella flexneri. patient was successfully treated with surgery and a course of ampicillin. | 1993 | 8511820 |
| ultrastructure of the surface film of bacterial colonies. | the structure of the surface of colonies of various gram-negative and gram-positive bacteria was examined by transmission electron microscopy. the results indicate that bacterial colonies in the course of their development produce a film which becomes thicker with increased duration of growth. the basic part of the film is an elementary membrane, which is a stable structure with a large surface area. the inner and outer surfaces of the film membrane are covered by amorphous layers. these layers ... | 1993 | 8515240 |
| molecular studies of plasmids of multiply-resistant shigella spp. in hong kong. | one hundred and two shigella spp. isolated in two hospitals in hong kong were analysed for antibiotic resistances, resistance plasmids and plasmid profiles. three quarters of the isolates were s. flexneri. all isolates harboured plasmids, up to a maximum of ten within one strain. plasmids of 220 kb encoding resistances to tetracycline, chloramphenicol and sulphonamide and probably also associated with invasiveness in the sereny test were found in 80 strains and were transferable in 18% of cases. ... | 1993 | 8519309 |
| identification of two targets of the type iii protein secretion system encoded by the inv and spa loci of salmonella typhimurium that have homology to the shigella ipad and ipaa proteins. | an important virulence factor of salmonella spp. is their ability to gain access to host cells. a type iii secretion system encoded in the inv and spa loci of these organisms is essential for this phenotype. we have identified two proteins, sipa and sipd, whose secretion from the bacterial cells is dependent on this system. the genes encoding these proteins are located at centisome 63 on the s. typhimurium chromosome, immediately downstream of the previously identified sipb and sipc genes (k. ka ... | 1995 | 8522512 |
| use of plasma desorption mass spectrometry in structural analysis of endotoxins: effects on lipid a of different acid treatments. | | 1995 | 8524917 |
| biological properties of yolk immunoglobulins. | | 1995 | 8526019 |
| identification and sequences of the treponema pallidum flim', fliy, flip, fliq, flir and flhb' genes. | information regarding the biology and virulence attributes of treponema pallidum (tp) is limited due to the lack of genetic exchange mechanisms and the inability to continuously cultivate this spirochete. we have utilized tnphoa mutagenesis of a tp genomic dna library in escherichia coli (ec) to identify genes encoding exported proteins, a subset of which are likely to be important in treponemal pathogenesis. we report here the identification and nucleotide (nt) sequence of a 5-kb treponemal dna ... | 1995 | 8529894 |
| viral diarrhoea in a rural coastal region of karnataka india. | a total of 106 children below 5 years of age admitted to the kasturba medical college hospital manipal karnataka (south india) were investigated over a period of 6 months to determine the aetiological role of viruses in acute diarrhoea. viral aetiological agents isolated were rotaviruses in 12 (11 per cent) cases, adenoviruses in 3 (3 per cent) cases, coronavirus and astroviruses in two (2 per cent) cases each. non-viral isolates were cryptosporidium and salmonella typhimurium in two cases each, ... | 1995 | 8531264 |
| shigellosis in children from north india: a clinicopathological study. | stool samples of 1488 children suffering from acute diarrhoea were studied for bacterial culture and sensitivity. shigella culture was positive in 143 (10 per cent) children and 53 hospitalized children could be studied in detail. thirty-six (68 per cent) children were under 2 years of age and peak prevalence was observed in summer months. fever and diarrhoea were universal features; 96 per cent had blood and mucus in the stools, but 32 per cent started with watery diarrhoea lasting 1-3 days fol ... | 1995 | 8531265 |
| extracellular transport of virg protein in shigella. | the ability of shigella to spread within and between epithelial cells is a prerequisite for causing bacillary dysentery and requires the function encoded by the virg gene on the large plasmid. the outer membrane virg (icsa) protein is essential for bacterial spreading by eliciting polar deposition of filamentous actin (f-actin) in the cytoplasm of epithelial cells. recent studies have indicated that an n-terminal 80-kda virg portion is exposed on the bacterial cell surface and released into the ... | 1995 | 8537341 |
| partial dna sequence of a beta-lactamase produced by a shigella flexneri strain. | a probe was constructed by radioactive labelling, and enzymatically a dna fragment of plasmid pmam-1, which codes for a beta-lactamase in shigella flexneri ucsm 129, was obtained by amplification of a small part of the gene using the polymerase chain reaction technique (pcr). since previous published work indicated that this beta-lactamase was of the tem type, the primers used to amplify the gene were two highly conserved dna regions in all tem beta-lactamases. a 500 bp dna probe was obtained wh ... | 1995 | 8538491 |