Publications

TitleAbstractYear(sorted descending)
Filter
PMID
Filter
high-throughput screening of the virulence regulator virf: a novel antibacterial target for shigellosis.shigella flexneri is a human enteropathogen that infects about 165 million people and claims more than 1 million lives per year worldwide. although shigellosis has been considered a disease of the "third world," like many other contagious diseases, it does occur in developed countries. the emergence of drug and multidrug-resistant strains of shigella emphasizes the need for novel antibiotic development. virf, an arac-type transcriptional regulator, is responsible for the expression of all downst ...201020237205
bacterial enteritis as a risk factor for childhood intussusception: a retrospective cohort study.to assess the relationship between bacterial enteritis and intussusception.201020138300
a repulsive electrostatic mechanism for protein export through the type iii secretion apparatus.many gram-negative bacteria initiate infections by injecting effector proteins into host cells through the type iii secretion apparatus, which is comprised of a basal body, a needle, and a tip. the needle channel is formed by the assembly of a single needle protein. to explore the export mechanisms of mxih needle protein through the needle of shigella flexneri, an essential step during needle assembly, we have performed steered molecular dynamics simulations in implicit solvent. the trajectories ...201020141759
characterisation of multidrug-resistant salmonella typhimurium 4,[5],12:i:- dt193 strains carrying a novel genomic island adjacent to the thrw trna locus.in 2006, monophasic, multidrug-resistant salmonella enterica spp. enterica serovar 4,[5],12:i:- strains appeared as a novel serotype in germany, associated with large diffuse outbreaks and increased need for hospitalisation. the emerging 4,[5],12:i:- strains isolated from patients in germany belong mainly to phage type dt193 according to the anderson phage typing scheme for s. typhimurium (stm) and exhibit at least a tetra-drug resistance. the strains have been shown to harbour stm-specific gifs ...201020303825
neutrophil antimicrobial proteins enhance shigella flexneri adhesion and invasion.shigella flexneri is an enteric pathogen that causes massive inflammation and destruction of the human intestinal epithelium. neutrophils are the first cells of the innate immune system recruited to the site of infection. these cells can attack microbes by phagocytosis, neutrophil extracellular trap (net) formation and degranulation. here, we investigated how neutrophil degranulation affects virulence and show that exposure of shigella to granular proteins enhances infection of epithelial cells. ...201020331641
identification of active site residues in the shigella flexneri glucosyltransferase gtrv.the serotype-specific glucosyltransferase, gtrv, is responsible for glucosylation of the o-antigen repeating unit of shigella flexneri serotype 5a strains. gtrv is an integral inner membrane protein with two essential periplasmic loops: the large loop 2 and the c-terminal loop 10. in this study, the full length of the loop 2 was shown to be necessary for gtrv function. site-directed mutagenesis within this loop revealed that conserved aromatic and charged amino acids have a critical role in the ...201020334579
[preparation of a 96-microwell plate dna diagnostic chip for detection of foodborne bacteria and its application in an incident of food poisoning].to develop a 96-microwell plate dna diagnostic chip for simultaneous detection of 9 major foodborne bacteria.201020335099
metal based biologically active compounds: design, synthesis, and antibacterial/antifungal/cytotoxic properties of triazole-derived schiff bases and their oxovanadium(iv) complexes.a new series of oxovanadium(iv) complexes have been designed and synthesized with a new class of triazole schiff bases derived from the reaction of 3,5-diamino-1,2,4-triazole with 2-hydroxy-1-naphthaldehyde, pyrrole-2-carboxaldehyde, pyridine-2-carboxaldehyde and acetyl pyridine-2-carboxaldehyde, respectively. physical (magnetic susceptibility, molar conductance), spectral (ir, (1)h nmr, (13)c nmr, mass and electronic) and analytical data have established the structures of these synthesized schi ...201020338672
a soluble form of the pilus protein fima targets the vdac-hexokinase complex at mitochondria to suppress host cell apoptosis.inhibition of apoptotic response of host cells during an early phase of infection is a strategy used by many enteroinvasive bacterial pathogens to enhance their survival. here, we report the identification of a soluble form of the pilus protein fima from the culture supernatants of e. coli k1, salmonella, and shigella that can potently inhibit bax-mediated release of cytochrome c from isolated mitochondria. similar to the infected cells, hct116 cells stably expressing fima display a delay in the ...201020347420
34 kda momp of shigella flexneri promotes tlr2 mediated macrophage activation with the engagement of nf-kappab and p38 map kinase signaling.the 34 kda major outer membrane protein (momp) of shigella flexneri 2a induces combinatorial expression of tlr2 and tlr6 on peritoneal macrophages of balb/c mice. between the two best-characterized tlrs, to date, tlr2 and tlr4, which are chiefly responsible for recognizing majority of bacterial products, tlr2 alone participates in recognition of 34 kda momp. in addition to tlrs, momp enhances the mrna expression of myd88 and traf6 and induces the nuclear translocation of nf-kappab as well as act ...201020347487
long-term downregulation of protease-activated receptor-2 expression in distal colon in rats following bacillary dysentery.the aim of this study was to determine changes of par-2 expression in distal colon and the sensitivity of colonic muscle to sligrl-nh2, the par-2-activating peptide (par-2-ap) following bacillary dysentery. shigella flexneri was administrated intragastrically in healthy male rats to induce bacillary dysentery. the effect of sligrl-nh2 on the motility of colonic muscle strips were examined. the expression of par-2 was determined by immunohistochemistry and western blotting. intragastric administr ...201020347884
antibiotics for the treatment of dysentery in children.ciprofloxacin, ceftriaxone and pivmecillinam are the antibiotics currently recommended by the world health organization (who) for the treatment of dysentery in children; yet there have been no reviews of the clinical effectiveness of these antibiotics in recent years.201020348130
global transcriptional response of macrophage-like thp-1 cells to shiga toxin type 1.shiga toxins (stxs) are bacterial cytotoxins produced by the enteric pathogens shigella dysenteriae serotype 1 and some serotypes of escherichia coli that cause bacillary dysentery and hemorrhagic colitis, respectively. to date, approaches to studying the capacity of stxs to alter gene expression in intoxicated cells have been limited to individual genes. however, it is known that many of the signaling pathways activated by stxs regulate the expression of multiple genes in mammalian cells. to ex ...201020351145
isolation and selection of coliphages as potential biocontrol agents of enterohemorrhagic and shiga toxin-producing e. coli (ehec and stec) in cattle.to isolate, characterize and select phages as potential biocontrol agents of enterohemorrhagic and shiga toxin-producing escherichia coli (ehec and stec) in cattle.201020353429
molecular architecture of the mn2+-dependent lactonase ulag reveals an rnase-like metallo-beta-lactamase fold and a novel quaternary structure.the ulag gene, located in the ula regulon, is crucial for the catabolism of l-ascorbate under anaerobic conditions and it has been proposed to encode for the putative l-ascorbate-6-p lactonase. the ulag gene is widespread among eubacteria, including human commensal and pathogenic genera such as escherichia, shigella, klebsiella and salmonella. here, we report the three-dimensional structures of the apoenzyme and mn(2+) holoenzyme of ulag from e. coli to 2.6 a resolution, determined using single- ...201020359483
modeling fimbriae mediated parasite-host interactions.type 1 fimbriae are a known virulence factor in a number of pathogenic enterobacteriaceae, including salmonella, shigella and e. coli. yet, they are also expressed by some commensal strains, notably of e. coli. one hypothesis of the role of fimbriae in commensals is that they evoke a small but tolerable host immune response in order to have the host release sialic acid, which is a valuable nutrient. genetic evidence suggests that sialic acid down-regulates fimbriation. this has been believed to ...201020359486
structure of shigella ipgb2 in complex with human rhoa: implications for the mechanism of bacterial guanine nucleotide exchange factor mimicry.a common theme in bacterial pathogenesis is the manipulation of eukaryotic cells by targeting the cytoskeleton. this is in most cases achieved either by modifying actin, or indirectly via activation of key regulators controlling actin dynamics such as rho-gtpases. a novel group of bacterial virulence factors termed the wxxxe family has emerged as guanine nucleotide exchange factors (gefs) for these gtpases. the precise mechanism of nucleotide exchange, however, has remained unclear. here we repo ...201020363740
isolation of bacteria from mouse caecal samples and description of bacteroides sartorii sp. nov.caecal samples from wild-type and tnf(deltaare) mice were cultured on selective media containing bile salts, amino acids or casein macro-peptides. twenty-two strains were isolated and identified by 16s rrna gene sequencing. twenty-one strains showed >98% similarity to known bacteria (blautia spp., clostridium innocuum, enterococcus spp., escherichia coli, lactobacillus murinus, parabacteroides goldsteinii and shigella dysenteriae). one additional isolate, strain a-c2-0, was a new bacterium. the ...201020369227
antibacterial effect of the bioactive compound beauvericin produced by fusarium proliferatum on solid medium of wheat.to obtain the bioactive compound beauvericin (bea), fusarium proliferatum cect 20569 was grown on a solid medium of wheat, utilizing the technique of the solid state fermentation (ssf), being this mycotoxin purified by high performance liquid chromatography (hplc) with a reverse phase semi-preparative column using as the mobile phase acetonitrile/water in gradient condition. the purity of the bea was verified by analytical hplc and liquid chromatography tandem mass spectrometry (lc/ms-ms). the p ...201020371252
the effects of a vegetable-derived probiotic lactic acid bacterium on the immune response.the objective of this study was to investigate the probiotic properties of the fermented vegetable derived lactic acid bacterium, l. plantarum. l. plantarum 10hk2 showed antibacterial activity against pathogenic bacteria and immunomodulating effects on murine macrophage cell lines. raw 264.7 cells stimulated with viable cells of this probiotic strain increased the amounts of pro-inflammatory mediators such as il-1beta, il-6 and tnf-alpha, as well as the anti-inflammatory mediator, il-10. icr mic ...201020377751
use of optical mapping to sort uropathogenic escherichia coli strains into distinct subgroups.optical maps were generated for 33 uropathogenic escherichia coli (upec) isolates. for individual genomes, the ncoi restriction fragments aligned into a unique chromosome map for each individual isolate, which was then compared with the in silico restriction maps of all of the sequenced e. coli and shigella strains. all of the upec isolates clustered separately from the shigella strains as well as the laboratory and enterohaemorrhagic e. coli strains. moreover, the individual strains appeared to ...201020378655
biological potentials and cytotoxicity of various extracts from endemic origanum minutiflorum o. schwarz & p.h. davis.the aim of the present study was to investigate antioxidative, antimicrobial and cytotoxic effects of endemic origanum minutiflorum (o. schwarz & p.h. davis). antioxidant activities of the extracts from o. minutiflorum were evaluated by using dpph radical scavenging, beta-carotene bleaching and metal chelating activity assays. in addition, the amounts of total phenol components in the plant extracts were determined. in the beta-carotene bleaching test, the extracts exhibited in the range of 58.1 ...201020381570
sensitivity and specificity of bloody diarrhea in shigella gastroenteritis.the sensitivity and specificity of bloody diarrhea in the diagnosis of shigella gastroenteritis in a shigella sonnei prevalent center was investigated. the shigella-proven gastroenteritis cases who were admitted to hacettepe university ihsan doğramaci children's hospital diarrheal diseases unit (jan 2003 - oct 2006) constituted the study group (n=65). age- and sex-matched children admitting to the same center with non-shigella diarrhea constituted the control group (n=65). the sensitivity, speci ...201021434533
the modulation of hela cells secretory patterns by invasive shigella spp. and enteroinvasive e. coli bacterial cells and their soluble components.considering the important role of cytokines in the initiation and evolution of the inflammatory process induced by shigella and eiec strains, the purpose of this study was the characterization of the secretory patterns of hela cells induced by shigella ssp. and eiec strains and to link the obtained results with the invasiveness level of bacterial strains on this cellular line. during this study there were analyzed two eiec strains and 12 strains of the following shigella species: 2 sh. flexneri ...201021434590
travelers' diarrhea in nepal: an update on the pathogens and antibiotic resistance.diarrhea is the most common illness among travelers and expatriates in nepal. published data on the etiology of travelers' diarrhea (td) in nepal are over 13 years old and no prior data exist on antibiotic susceptibility for currently used drugs. we investigated the etiology of diarrhea and antimicrobial susceptibility pattern of bacterial pathogens and compared the results to previous work from the same clinical setting.201021366793
akara ogbomoso: microbiological examination and identification of hazards and critical control points.akara ogbomoso was examined toward the establishment of hazard analysis and critical control point (haccp). the akara was produced in residential buildings with the attendant consequence of contamination. there was ample growth of aerobes, coliforms, staphylococci, shigella and yeast/mold from the samples, water and cowpea pastes. microbial contaminations occur through the processing, which can be corrected through education by adopting good hygienic and manufacturing practices. the critical con ...201021339157
microbial evaluation and public health implications of urine as alternative therapy in clinical pediatric cases: health implication of urine therapy.cultural means of pediatric treatment during ill health is a mainstay in africa, and though urine has been known to contain enteric pathogens, urine therapy is still culturally applicable in some health conditions and also advocated as alternative therapy. the study therefore, is to evaluate the microbial contents and safety of urine.201021293739
antibacterial activity of thai medicinal plants pikutbenjakul.bacterial infections caused by resistant strains have been increased dramatically. pikutbenjakul, a thai medicinal plant formula containing piper longum, piper sarmentosum, piper interruptum, plumbago indica and zingiber officinale have been widely used in thai traditional medicine.201021298838
proinflammatory fecal mrna and childhood bacterial enteric infections.introduction: assessment of specific mrnas in human samples is useful in characterizing disease. however, mrna in human stool has been understudied. results: compared to controls, infected stools showed increased transcripts of il-1β, il-8 and calprotectin. mrna and protein concentrations correlated for il-8, but not for calprotectin. discussion: stool mrna quantification offers a potentially useful, noninvasive way to assess inflammation in the gastrointestinal tract, and may be more sensitive ...201021327027
infectious diarrhea: cellular and molecular mechanisms.diarrhea caused by enteric infections is a major factor in morbidity and mortality worldwide. an estimated 2-4 billion episodes of infectious diarrhea occur each year and are especially prevalent in infants. this review highlights the cellular and molecular mechanisms underlying diarrhea associated with the three classes of infectious agents, i.e., bacteria, viruses and parasites. several bacterial pathogens have been chosen as model organisms, including vibrio cholerae as a classical example of ...201021327112
mixed infections of vibrio cholerae o1 ogawa el tor with shigella dysenteriae.mixed infections caused by enteric pathogens such as bacteria, virus, protozoa and helminthes were reported in different literatures. this report also describes the co-infections caused by vibrio cholerae o1 ogawa el tor with shigella dysenteriae in a patient. a 36-year-old man was admitted in fatemeh zahra hospital of bushehr iran with fever, vomiting and dysentery. his stool sample was cultured, for identification purposes tcbs, xld and other media were used. v. cholerae and s. dysenteriae wer ...201021313886
virulence of environmental stenotrophomonas maltophilia serologically cross-reacting with shigella-specific antisera.this research involved an environmental strain of stenotrophomonas maltophilia which has been reported to produce serological cross-reactivity with shigella dysenteriae type 8 specific antisera. since clinical diagnosis of shigellosis is largely based on culture and serology, the investigation was aimed at in vivo and in vitro virulence comparison between the culturally similar environmental s. maltophilia isolate and the reference s. dysenteriae strains. the findings of this study revealed the ...201021313916
bacteriological profile and resistant pattern of clinical isolates from pediatric patients, gondar university teaching hospital, gondar, northwest ethiopia.infectious diseases are major causes of morbidity and mortality among children in the developing world antibiotic resistance is increasing. knowledge of pathogens causing infection in pediatrics patients is essential for devising management strategies.201021280431
[type three secretion system and pathogenesis of shigella spp.--a review].the powerful weapon of shigella spp. is type three secretion system, which remains the focus of pathogenic research. the regulation and function of type three secretion system of shigella spp. are summarized in this review.201021268888
ceftriaxone resistant shigella flexneri, an emerging problem.shigellosis is a disease of public health importance in developing countries. it may cause self-limited diarrhea to severe dysentery. emergence of multi drug resistant (mdr) strains is a growing concern globally. ceftriaxone and ciprofloxacin are the drugs of choice for mdr cases. here, we report a case of mdr shigella flexneri from an immunocompromised patient. the strain was resistant to ceftriaxone [minimum inhibitory concentration (mic) ≥ 64 μg/ml], limiting the treatment option. simultaneou ...201021258157
prevalent organisms on ostrich carcasses found in a commercial abattoir.the prevalent microbial growth on carcasses before and after overnight cooling in an ostrich abattoir and de-boning plant was investigated. the effect of warm or cold trimming of the carcasses was examined together with possible causes of contamination along the processing line. an attempt was made to link the prevalent microorganisms that were identified from carcasses to those from specific external contamination sources. samples of carcasses and possible contaminants were collected in the pla ...201021247040
synthesis and evaluation of a class of new coumarin triazole derivatives as potential antimicrobial agents.a series of new coumarin-based 1,2,4-triazole derivatives were designed, synthesized and evaluated for their antimicrobial activities in vitro against four gram-positive bacteria (staphylococcus aureus, mrsa, bacillus subtilis and micrococcus luteus), four gram-negative bacteria (escherichia coli, proteus vulgaris, salmonella typhi and shigella dysenteriae) as well as three fungi (candida albicans, saccharomyces cerevisiae and aspergillus fumigatus) by two-fold serial dilution technique. the bio ...201021215620
imperatorin a furocoumarin inhibits periplasmic cu-zn sod of shigella dysenteriae their by modulates its resistance towards phagocytosis during host pathogen interaction.shigella dysenteriae continues to be a major health problem, which leads to death, due to diarrhoea and dysentery, predominantly in children below the age of 5. bacterial invasion of the colonic epithelium leads to severe inflammation together with bacterial dissemination generates abscesses and ulcerations. periplasmic copper, zinc super oxide dismutase of shigella protects it from exogenous superoxide produced by host, during its invasion. hence, in present study an attempt was made to study t ...201021194882
cutting edge: nlrc5-dependent activation of the inflammasome.the nucleotide-binding domain leucine-rich repeat-containing proteins, nlrs, are intracellular sensors of pathogen-associated molecular patterns and damage-associated molecular patterns. a subgroup of nlrs can form inflammasome complexes, which facilitate the maturation of procaspase 1 to caspase 1, leading to il-1β and il-18 cleavage and secretion. nlrc5 is predominantly expressed in hematopoietic cells and has not been studied for inflammasome function. rna interference-mediated knockdown of n ...201021191067
molecular structure and vibrational spectra of three substituted 4-thioflavones by density functional theory and ab initio hartree-fock calculations.the vibrational frequencies of three substituted 4-thioflavones in the ground state have been calculated using the hartree-fock and density functional method (b3lyp) with 6-31g* and 6-31+g** basis sets. the structural analysis shows that there exists h-bonding in the selected compounds and the hydrogen bond lengths increase with the augment of the conjugate parameters of the substituent group on the benzene ring. a complete vibrational assignment aided by the theoretical harmonic wavenumber anal ...201021156350
notes from the field: emergence of shigella flexneri 2a resistant to ceftriaxone and ciprofloxacin --- south carolina, october 2010.on october 20, 2010, the south carolina department of health and environmental control and cdc began investigating a cluster of three diarrheal illnesses caused by multidrug-resistant shigella flexneri 2a. the index case occurred in a girl aged 2 years who experienced the onset of diarrhea on september 25 and was hospitalized the next day because of a seizure and fever. on september 30, her brother, aged 6 years, was hospitalized with vomiting, bloody diarrhea, and hyponatremia. three days later ...201021160457
[study on the integration site and arrangement of sfii and sfx prophages in shigella flexneri serotype 2b strains.]objective: to study the integration site and arrangement of sfii and sfx prophages in shigella flexneri serotype 2b strains. methods: a series of primers were designed based on potential integration site of sfii and sfx prophages in shigella flexneri serotype 2b strains, and pcr were performed for 50 serotype 2b strains to amplify special genes located in host and prophages. pcr products were sequenced to identify integration sites and arrangement of sfii and sfx. results: in all the serotype 2b ...201021162847
emergence of a novel shigella flexneri serotype 4s strain that evolved from a serotype x variant in china.this paper describes the first isolation of a new shigella flexneri serotype, designated 4s, in beijing, china. genotypic and phenotypic profiling suggests that this isolate is a clone of the s. flexneri serotype x variant reference strain. of particular concern is the multidrug resistance exhibited by this isolate.201021177890
reinforcement of epithelial cell adhesion to basement membrane by a bacterial pathogen as a new infectious stratagem.the intestinal epithelium undergoes a rapid turnover in addition to rapid exfoliation in response to bacterial infection, thus acting as an intrinsic defense against microbial intruders. it has long been questioned how mucosal pathogens can circumvent the intestinal defense systems. our recent discovery of a bacterial ploy used by shigella provided us with fresh insight. shigella delivers ospe via the type iii secretion system during multiplication within epithelial cells. this effector protein ...201021178415
mapping the selection mechanisms by bacterial gefs.mimicry of eukaryotic signaling enzymes is a common strategy used by bacterial pathogens to manipulate host cellular signaling. the e. coli type iii effector protein map belongs to a large family of bacterial virulence factors that activate host rho gtpase signaling pathways through an unknown molecular mechanism. our recent structural study, coupled with biochemical and functional assays, establishes that this family protein, including map, ipgb1/2 and sifa/b secreted by e. coli, shigella, and ...201021178423
convergent synthesis of a common pentasaccharide corresponding to the o-antigen of escherichia coli o168 and shigella dysenteriae type 4.a convenient synthetic strategy of the common acidic pentasaccharide repeating unit corresponding to the o-antigen of enterotoxigenic e. coli o168 and shigella dysenteriae type 4 has been successfully developed. a stereoselective [2 + 3] block glycosylation method has been exploited to get the target pentasaccharide derivative. most of the synthetic intermediates were solid and prepared in high yields from commercially available reducing sugars following a series of protection-deprotection react ...201021181263
evaluation of antibacterial activity of 3-butenyl, 4-pentenyl, 2-phenylethyl, and benzyl isothiocyanate in brassica vegetables.this study investigated antibacterial activities of 4 isothiocyanates (3-butenyl, 4-phentenyl, 2-phenylethyl, and benzyl isothiocyanate) against 4 gram-positive bacteria (bacillus cereus, bacillus subtilis, listeria monocytogenes, and staphylococcus aureus) and 7 gram-negative bacteria (aeromonas hydrophila, pseudomonas aeruginosa, salmonella choleaesuis, salmonella enterica, serratia marcescens, shigella sonnei, and vibrio parahaemolyticus) by an agar disc diffusion assay. benzyl isothiocyanate ...201021535549
osmosonication of blackberry juice: impact on selected pathogens, spoilage microorganisms, and main quality parameters.osmosonication combines ultrasound with nonthermal concentration. it was applied on tropical highland blackberry (rubus adenotrichus) juice over different periods of time to assess reductions in microorganism and the impact on main quality parameters. this juice had been inoculated with salmonella spp., shigella sp., a lactic acid bacterium, yeasts, and molds. it was then sonicated for 5.9 to 34.1 min at 20 khz and 0.83 w/ml. nonthermal concentration was simulated by mixing the juice with a conc ...201021535558
lactobacillus fermentum isolated from human colonic mucosal biopsy inhibits the growth and adhesion of enteric and foodborne pathogens.a number of lactobacillus species are used as probiotic strains in order to benefit health. we have isolated l. fermentum from human colonic mucosal biopsy samples that possess antimicrobial activities against entroinvasive and foodborne pathogens such as escherichia coli, salmonella paratyphi a, shigella sonnei, staphylococcus aureus, enterococcus faecalis, proteus mirabilis, pseudomonas aeruginosa, and vibrio sp. in addition to lactic acid, l. fermentum secretes antimicrobial proteinacious com ...201021535608
effect of nacl on the biofilm formation by foodborne pathogens.this study was designed to evaluate the effect of nacl on the biofilm formation of listeria monocytogenes, staphylococcus aureus, shigella boydii, and salmonella typhimurium. the biofilm cells were cultured in media containing different nacl concentrations (0% to 10%) for 10 d of incubation at 37 °c using a 24-well polystyrene microtiter plate, collected by swabbing methods, and enumerated using plate count method. the attachment and detachment kinetic patterns were estimated according to the mo ...201021535614
[shigellosis--epidemiological situation in montenegro in period 1996-2005].introduction shigellosis is the most common cause of diarrhoea in the world. it is estimated to cause 165 million cases per a year, and two third of all diseases and most of the deaths are among children under 10 years of age. the aim of this descriptive epidemiologic study was to analyze the incidence of shigellosis in montenegro during the period 1996-2005 and to find out which species of shigella were dominant in this region.201021446148
shiga toxins: intracellular trafficking to the er leading to activation of host cell stress responses.despite efforts to improve hygenic conditions and regulate food and drinking water safety, the enteric pathogens, shiga toxin-producing escherichia coli (stec) and shigella dysenteriae serotype 1 remain major public health concerns due to widespread outbreaks and the severity of extra-intestinal diseases they cause, including acute renal failure and central nervous system complications. shiga toxins are the key virulence factors expressed by these pathogens mediating extra-intestinal disease. de ...201022069648
enterobacteriaceae associated with eggs of podocnemis expansa and podocnemis unifilis (testudines:chelonia) in nonpolluted sites of national park of araguaia plains, brazil.fertile eggs of podocnemis expansa and podocnemis unifilis were investigated for the presence of enterobacteria, as these two endangered species have the potential for conservation measures that include egg transfer. knowledge of normal microflora associated with turtles and turtle eggs would help effectively manage the transfer of these eggs among institutions. thirty eggs of each species were collected, aseptically transferred, cracked inside plastic bags containing tetrathionate broth, and sp ...201021370647
ribonucleases and bacterial virulence.bacterial stress responses provide them the opportunity to survive hostile environments, proliferate and potentially cause diseases in humans and animals. the way in which pathogenic bacteria interact with host immune cells triggers a complicated series of events that include rapid genetic re-programming in response to the various host conditions encountered. viewed in this light, the bacterial host-cell induced stress response (hcisr) is similar to any other well-characterized environmental str ...201021375713
shiga toxin is transported into the nucleoli of intestinal epithelial cells via a carrier-dependent process.shiga toxin (stx) produced by the invasive shigella dysenteriae serotype 1 (s. dysenteriae1) causes gastrointestinal and kidney complications. it has been assumed that stx is released intracellularly after enterocyte invasion by s. dysenteriae1. however, there is little information about stx distribution inside s. dysenteriae1-infected enterocytes. here, we use intestinal epithelial t84 cells to characterize the trafficking of stx delivered into the cytosol, in ways that mimic aspects of s. dyse ...201022069640
serine protease autotransporters of enterobacteriaceae (spates): biogenesis and function.serine protease autotransporters of enterobacteriaceae (spates) constitute a large family of proteases secreted by escherichia coli and shigella. spates exhibit two distinct proteolytic activities. first, a c-terminal catalytic site triggers an intra-molecular cleavage that releases the n-terminal portion of these proteins in the extracellular medium. second, the secreted n-terminal domains of spates are themselves proteases; each contains a canonical serine-protease catalytic site. some of thes ...201022069633
cytoskeleton-modulating effectors of enteropathogenic and enterohemorrhagic escherichia coli: a case for espb as an intrinsically less-ordered effector.enterohemorrhagic and enteropathogenic escherichia coli produce various effector proteins that are directly injected into the host-cell cytosol through the type iii secretion system. e. coli secreted protein (esp)b is one such effector protein, and affects host-cell morphology by reorganizing actin networks. unlike most globular proteins that have well-ordered, rigid structures, the structures of type iii secretion system effectors from pathogenic gram-negative bacteria, including espb, are ofte ...201020477867
[campylobacter spp. as a leading cause of human bacterial gastroenteritis in selected region of poland].the results of the epidemiological analysis of campylobacteriosis reported by regional laboratory of sanitary epidemiological station in bielsko-biala (psse bielsko-biala), silesia voivodeship in poland are presented. from august 2006 to july 2009, stool samples from diarrhea cases were examined for the presence of campylobacter spp. as well as salmonella, shigella, yersinia, enteropathogenic (epec) and verotoxigenic (vtec) e. coli. the most frequently isolated species of campylobacter spp. was ...200920120952
[prof. kazimierz lachowicz (md)--100th anniversary of birthday].prof. kazimierz lachowicz, md, dipl. medical microbiology, was the founder and the first director of the three regional branches of national institute of hygiene (nih),--in stanisławów (eastern poland) (1937-43), now in ukrainian ivano-frankivsk, maritime in gdynia (1945), now institute of maritime and tropical medicine, and in gdańsk (1945-52). in nih, warsaw, 1953-75 he directed intestinal infection laboratory of bacteriological dept., later founded and directed the national shigella centre as ...200920120962
highly sensitive detection of shigella flexneri using fluorescent silica nanoparticles.robust signal amplification tactic is a good solution for improving detection sensitivity. unprocessed fluorophores have many limitations. here we describe an effective strategy for highly sensitive detection of bacteria by using fluorescent conjugated nanoparticles. the nanoparticles were synthesized using silica as matrix. fluorescein isothiocyanate distributed in the matrix. s. flexneri specific antibody was coated on the surface of the nanoparticles. compared to the traditional fluorescent a ...200920128444
resistances of antibiotics and heavy metals in enterobacteriaceae spp. isolated from gills and intestines of achanthobrama marmid (heckel,1843) from sir dam lake turkey.a total of 94 bacteria, associated with wild achanthobrama marmid (heckel, 1843) in sir dam lake of turkey identified. subsequently selected isolates were characterized and identified to the genus level the 94 members of enterobacteriaceae were isolated in the gills and intestines, and among the isolates, e. coli were represented at a rate of 55%, shigella spp. at a rate of 21%, salmonella spp. at a rate of 9%, citrobacter spp. at a rate of 9%, klebsiella spp. at a rate of 3% and proteus spp., a ...200920112859
prevalence of intestinal parasitic and bacterial pathogens in diarrhoeal and non-diarroeal human stools from vhembe district, south africa.in the present study, a cross-sectional survey of intestinal parasitic and bacterial infections in relation to diarrhoea in vhembe district and the antimicrobial susceptibility profiles of isolated bacterial pathogens was conducted. stool samples were collected from 528 patients attending major public hospitals and 295 children attending two public primary schools and were analyzed by standard microbiological and parasitological techniques. entamoeba histolytica/e. dispar (34.2%) and cryptospori ...200920099757
[the effect of trimethoprim-sulfamethoxazole in blastocystis hominis infection].the aim of this study was to investigate clinical findings and the effects of trimethoprim-sulfamethoxazole (tmp-smx) in cases of blastocystosis. a total of 37 cases whose stool specimens were sent to the parasitology laboratory from the outpatient clinics of our hospital for various reasons were included in the study. only five or more blastocystis hominis were found during examination with direct wet mount using the 40x objective. the stool specimens were tested for other agents (salmonella sp ...200920101575
antimicrobial resistance induced by genetic changes.decoding the mechanisms of resistance to antibiotics is essential in fighting a phenomenon, which is amplifying everyday due to the uncontrolled excessive and many times unjustified use of anti-microbial substances. at present it has become a matter of public health, together with the resistance of mycobacterium tuberculosis to tuberculostatic or the spreading of the aids virus which not only affects the european countries but the entire globe. this paper presents the genic mutations taking plac ...200920108530
[characteristics of dysentery-causing strains isolated from patients and carriers in republic of south ossetia during period of humanitarian disaster]. 200920095424
diarrhea associated hemolytic uremic syndrome: a 3-year picu experience from nepal. 200920072865
diarrheagenic escherichia coli in sub-saharan africa: status, uncertainties and necessities.diarrhea is a leading cause of illness and death, particularly in developing countries. enteropathogenic escherichia coli, enterotoxigenic e. coli (etec), enteroinvasive e. coli, enterohemorrhaghic e. coli (ehec), enteroaggregative e. coli (eaec) and diffusely adherent e. coli (daec) have been associated with diarrheal disease in different parts of africa, particularly among young children, hiv-positive individuals, and visitors from abroad. each of these e. coli pathotypes uses distinct mechani ...200920061678
the immunogenic siga enterotoxin of shigella flexneri 2a binds to hep-2 cells and induces fodrin redistribution in intoxicated epithelial cells.we have previously shown that the enterotoxin siga which resides on the she pathogenicity island (pai) of s. flexneri 2a is an autonomously secreted serine protease capable of degrading casein. we have also demonstrated that siga is cytopathic for hep-2 cells and plays a role in the intestinal fluid accumulation associated with s. flexneri infections.200920011051
enteric pathogens in hiv/aids from a tertiary care hospital.patterns of enteric infections in hiv in developing countries may differ in several important ways from developed countries, the knowledge of which can often guide therapy when resource limitations hamper the exact diagnosis of the etiological agent in hiv-associated diarrhea.200920049303
[overdiagnosis of amebiasis in children with dysentery].there are morphologically identical amebaes, but with differences that can distinguish them; one as pathogenic: entamoeba histolytica, and the other: entamoeba dispar, as inoffensive. that brought the new hypothesis that many of the cases treated as amebiasis, weren't so.200920049395
bacterial effector binding to ribosomal protein s3 subverts nf-kappab function.enteric bacterial pathogens cause food borne disease, which constitutes an enormous economic and health burden. enterohemorrhagic escherichia coli (ehec) causes a severe bloody diarrhea following transmission to humans through various means, including contaminated beef and vegetable products, water, or through contact with animals. ehec also causes a potentially fatal kidney disease (hemolytic uremic syndrome) for which there is no effective treatment or prophylaxis. ehec and other enteric patho ...200920041225
antibacterial and antifungal activities of some mexican medicinal plants.in mexico about 4,000 plant species have some medicinal use. the aim of this work was to evaluate the antimicrobial activity of six mexican medicinal plants against fungi and gram-positive and gram-negative bacteria. methanolic extracts were prepared from the mexican medicinal plants amphypteringium adstrigens, castella tortuosa, coutarea latiflora, ibervillea sonorae, jatropha cuneata, and selaginella lepidophylla. the antibacterial and antifungal activities of the plants were determined by the ...200920041800
multilocus variable-number tandem repeat analysis for molecular typing and phylogenetic analysis of shigella flexneri.shigella flexneri is one of the causative agents of shigellosis, a major cause of childhood mortality in developing countries. multilocus variable-number tandem repeat (vntr) analysis (mlva) is a prominent subtyping method to resolve closely related bacterial isolates for investigation of disease outbreaks and provide information for establishing phylogenetic patterns among isolates. the present study aimed to develop an mlva method for s. flexneri and the vntr loci identified were tested on 242 ...200920042119
trends in antimicrobial resistance in shigella species in karachi, pakistan.shigellosis is a common cause of morbidity, especially in the very young and old, in developing countries. the disease is treated with antibiotics. surveillance of antimicrobial resistance trends is essential owing to the global emergence of antimicrobial resistance.200920009283
helicobacter pylori induces mapk phosphorylation and ap-1 activation via a nod1-dependent mechanism.helicobacter pylori rapidly activates mapks and transcription factors, nf-kappab and ap-1, in gastric epithelial cells following host attachment. activation of these signal transducers is largely dependent on the cag pathogenicity island (cagpai)-encoded type iv secretion system. h. pylori was shown to translocate peptidoglycan through the type iv secretion system, which is recognized by the pathogen recognition molecule, nod1, thus resulting in nf-kappab activation. the mechanisms of h. pylori- ...200920007577
a changing picture of shigellosis in southern vietnam: shifting species dominance, antimicrobial susceptibility and clinical presentation.shigellosis remains considerable public health problem in some developing countries. the nature of shigellae suggests that they are highly adaptable when placed under selective pressure in a human population. this is demonstrated by variation and fluctuations in serotypes and antimicrobial resistance profile of organisms circulating in differing setting in endemic locations. antimicrobial resistance in the genus shigella is a constant threat, with reports of organisms in asia being resistant to ...200920003464
[development of taqman real-time pcr in detection of aeromonas hydrophila].to develop a taqman real-time pcr for the detection of aeromonas hydrophila.200919954074
[investigation of a norovirus outbreak through contaminated centralized water supply system].to investigate the etiology and source of an infectious diarrhea outbreak and control the epidemic.200919954078
purification, characterization, and gene cloning of glucose-1-phosphatase from citrobacter braakii.citrobacter braakii produced an intracellular acid glucose phosphatase (agpc) which was purified 986 fold to homogeneity with the specific activity of 286 units/mg. agpc hydrolyzed a wide variety of phosphorylated compounds with high activity for glucose-1-phosphate and glucose-6-phosphate. the optimum ph and temperature for the enzyme activity was ph 5.0 and 45 degrees c, respectively. the km value for glucose-1-phosphate was 5.12 mm with a vmax 27.8 u mg(-1). its molecular weight was 46 kda by ...200919940380
vaccines for enteric diseases: update on recent developments.the 5th international conference on vaccines for enteric diseases (ved) attracted more than 250 delegates, mainly from industrialized countries. a total of 56 papers were presented and 46 posters were displayed to update recent developments in the field of enteric diseases and vaccine development. this 3-day event enabled academic research institutions, pharmaceutical and biotech companies, and international donors to get a sense of what has been going on since the last ved conference in 2007. t ...200919943760
inactivated and subunit vaccines to prevent shigellosis.shigellosis remains a formidable disease globally, with children of the developing world bearing the greatest number of infections. the need for an affordable, safe and efficacious vaccine has persisted for decades. vaccines to prevent shigellosis can be divided into living and nonliving approaches. several nonliving shigella vaccines are currently at different stages of development and show substantial promise. outlined here is an overview of multiple nonliving vaccine technologies, highlightin ...200919943764
studies on the antidiarrhoeal activity of aegle marmelos unripe fruit: validating its traditional usage.aegle marmelos (l.) correa has been widely used in indigenous systems of indian medicine due to its various medicinal properties. however, despite its traditional usage as an anti-diarrhoeal there is limited information regarding its mode of action in infectious forms of diarrhoea. hence, we evaluated the hot aqueous extract (decoction) of dried unripe fruit pulp of a. marmelos for its antimicrobial activity and effect on various aspects of pathogenicity of infectious diarrhoea.200919930633
a unified approach to molecular epidemiology investigations: tools and patterns in california as a case study for endemic shigellosis.shigellosis causes diarrheal disease in humans from both developed and developing countries, and multi-drug resistance is an emerging problem. the objective of this study is to present a unified approach that can be used to characterize endemic and outbreak patterns of shigellosis using use a suite of epidemiologic and molecular techniques. the approach is applied to a california case study example of endemic shigellosis at the population level.200919930709
spatial distribution of diarrhoea and microbial quality of domestic water during an outbreak of diarrhoea in the tshikuwi community in venda, south africa.total microbial quality assessment and geographical information system were used for evaluating the quality of water and the spatial distribution of diarrhoea cases in tshikuwi, a rural community in south africa, during an outbreak of diarrhoea. the water-abstraction points included two groundwater storage tanks, namely tank 1 and tank 2 and the khandanama river. indicator microbial counts for total coliforms, faecal coliforms, enterococci, and heterotrophic bacteria exceeded the limit for no ri ...200919902801
in this issue.shigellosis, dysentery - by whatever name - don't kiss the chimps: pp. 5029-5045with a 10-15% mortality rate when untreated in young children and immunedeficient patients, over one million deaths per year are attributable to this primate/human-only disease. furthermore, the shigella spp. have developed resistance to b-lactam, tetracycline, and aminoglycoside antibiotics very rapidly. a non-primate model of the disease is based on gnotobiotic piglets. aerobically grown bacteria shift to anaerobic ...200919921678
enteroinvasive escherichia coli vs. shigella flexneri: how different patterns of gene expression affect virulence.important features of the enteroinvasive escherichia coli (eiec) phenotype and gene expression likely to confer eiec with a lower ability to cause disease than shigella flexneri were described here for the first time. to confirm the lower pathogenicity of eiec, we have analyzed the keratoconjunctivitis developed in guinea-pigs with eiec or s. flexneri. shigella flexneri induced a more pronounced proinflammatory response, whereas eiec induced a mild form of the disease. eiec showed a significantl ...200919889166
pneumonia caused by shigella sonnei in man returned from india. 200919891897
computational study of the conformational structures of saccharides in solution based on j couplings and the "fast sugar structure prediction software".this article reports on the implementation of j coupling calculations in our recently developed fast sugar structure prediction software (fsps). the fsps combines a smart and exhaustive algorithm to search through conformational space with the calculation of different experimental nuclear magnetic resonance observables to establish the conformation of saccharides in solution. using our algorithm in combination with nmr data, we investigate the solution structure of three simple disaccharides (me ...200919795837
overseas outbreaks of infectious intestinal disease identified in scotland, 2003 to 2007.this article presents information on all potential outbreaks of infectious intestinal disease (iid) identified by health protection scotland (hps) involving residents of scotland. unlike other systems, this alert system covers potential outbreaks of iid rather than apparently sporadic cases and covers all gastrointestinal pathogens, all visited countries, and all groups of travelers.200919796102
escherichia coli as reservoir for macrolide resistance genes.the plasmid-borne mph(a) gene that confers resistance to azithromycin and has recently emerged in shigella sonnei is present in multidrug- and non-multidrug-resistant escherichia coli isolates from 4 continents. further spread of mph(a) to shigella and salmonella spp. may be expected.200919861064
uropathogenic escherichia coli suppresses the host inflammatory response via pathogenicity island genes sisa and sisb.extraintestinal pathogenic escherichia coli can successfully colonize the urinary tract of the immunocompetent host. in part, this is accomplished by dampening the host immune response. indeed, the sisa and sisb genes (shia-like inflammation suppressor genes a and b) of uropathogenic e. coli strain cft073, homologs of the shigella flexneri shi-2 pathogenicity island gene shia, suppress the host inflammatory response. a double deletion mutant (deltasisa deltasisb) resulted in a hyperinflammatory ...200919797063
effects of enteropathogenic bacteria & lactobacilli on chemokine secretion & toll like receptor gene expression in two human colonic epithelial cell lines.the intestinal epithelium is part of the innate immune system responding to contact with pathogenic or commensal bacteria. the objective of this study was to compare innate responses of intestinal epithelial cell lines to pathogenic bacteria and to lactobacilli.200919797815
[dysentery and amoebiasis in poland in 2007].the number as well as incidence rate of notified as shigellosis, bacillary dysentery cases in xxi century are low. only 64 cases were notified in the year 2007 (incidence rate 0.17/100,000 population), while 35 (incidence rate 0.09) were notified in 2006 and median in the 2001-2005 years was 80, incidence rate 0.21/100,000 population. since 2000 no one-death case was notified. seven imported cases were notified as they got infection being abroad, in egypt 6: 4 cases got s. flexneri, two s. sonne ...200919799247
proteome analysis of an attenuated francisella tularensis dsba mutant: identification of potential dsba substrate proteins.francisella tularensis (f. tularensis) is highly infectious for humans via aerosol route and untreated infections with the highly virulent subsp. tularensis can be fatal. our knowledge regarding key virulence determinants has increased recently but is still somewhat limited. surface proteins are potential virulence factors and therapeutic targets, and in this study, we decided to target three genes encoding putative membrane lipoproteins in f. tularensis lvs. one of the genes encoded a protein w ...200919799467
antibiotic resistance among shigella serogroups isolated in tehran, iran (2002-2004). 200919801811
autophagy in immunity against intracellular bacteria.autophagy is an innate immune defense mechanism against various intracellular bacterial pathogens, such as salmonella enterica serovar typhimurium (s. typhimurium), listeria monocytogenes and shigella flexneri. s. typhimurium uses type three secretion systems (t3sss) to invade mammalian cells and replicate in salmonella-containing vacuoles (scvs). a small population of intracellular s. typhimurium is targeted by autophagy shortly after infection. evidence suggests that these bacteria are present ...200919802566
spa15 of shigella flexneri is secreted through the type iii secretion system and prevents staurosporine-induced apoptosis.shigella flexneri is a gram-negative, facultative intracellular pathogen that invades the colonic epithelium and causes bacillary dysentery. we previously demonstrated that s. flexneri inhibits staurosporine-induced apoptosis in infected epithelial cells and that a deltamxie mutant is unable to inhibit apoptosis. therefore, we hypothesized that an mxie-regulated gene was responsible for protection of epithelial cells from apoptosis. analysis of all mxie-regulated genes yielded no mutants that la ...200919805534
shigella infection of intestinal epithelium and circumvention of the host innate defense system.shigella, gram-negative bacteria closely related to escherichia coli, are highly adapted human pathogens that cause bacillary dysentery. although shigella have neither adherence factors nor flagella required for attaching or accessing the intestinal epithelium, shigella are capable of colonizing the intestinal epithelium by exploiting epithelial-cell functions and circumventing the host innate immune response. during shigella infection, they deliver many numbers of effectors through the type iii ...200919812985
the shigella dysenteriae serotype 1 proteome, profiled in the host intestinal environment, reveals major metabolic modifications and increased expression of invasive proteins.shigella dysenteriae serotype 1 (sd1) causes the most severe form of epidemic bacillary dysentery. we present the first comprehensive proteome analysis of this pathogen, profiling proteins from bacteria cultured in vitro and bacterial isolates from the large bowel of infected gnotobiotic piglets (in vivo). overall, 1061 distinct gene products were identified. differential display analysis revealed that sd1 cells switched to an anaerobic energy metabolism in vivo. high in vivo abundances of amino ...200919813213
comparative genomics reveal the mechanism of the parallel evolution of o157 and non-o157 enterohemorrhagic escherichia coli.among the various pathogenic escherichia coli strains, enterohemorrhagic e. coli (ehec) is the most devastating. although serotype o157:h7 strains are the most prevalent, strains of different serotypes also possess similar pathogenic potential. here, we present the results of a genomic comparison between ehecs of serotype o157, o26, o111, and o103, as well as 21 other, fully sequenced e. coli/shigella strains. all ehecs have much larger genomes (5.5-5.9 mb) than the other strains and contain sur ...200919815525
Refresh
firstprev
12345678910...
nextlast
Displaying items 601 - 700 of 13650