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a five-year antimicrobial resistance pattern of shigella isolated from stools in the gondar university hospital, northwest ethiopia.shigellosis is a global health problem. however, developing countries, where there is poor hygiene and unsafe water supplies, are especially affected. in the last two decades shigella isolates have become increasingly resistant to many commonly used drugs. we investigated the antibiotic susceptibility pattern of shigella isolated from stool specimens processed over five years in the bacteriology laboratory of the university of gondar teaching hospital in northwest ethiopia. stool specimens were ...200818302868
structures of the shigella flexneri type 3 secretion system protein mxic reveal conformational variability amongst homologues.many gram-negative pathogenic bacteria use a complex macromolecular machine, known as the type 3 secretion system (t3ss), to transfer virulence proteins into host cells. the t3ss is composed of a cytoplasmic bulb, a basal body spanning the inner and outer bacterial membranes, and an extracellular needle. secretion is regulated by both cytoplasmic and inner membrane proteins that must respond to specific signals in order to ensure that virulence proteins are not secreted before contact with a euk ...200818304577
the o-polysaccharide of escherichia coli o112ac has the same structure as that of shigella dysenteriae type 2 but is devoid of o-acetylation: a revision of the s. dysenteriae type 2 o-polysaccharide structure.the o-antigen structure of shigella dysenteriae type 2 was reinvestigated using chemical modifications along with high-resolution 2d (1)h and (13)c nmr spectroscopy. the o-antigen was found to contain a pyruvic acid acetal, which was overlooked in an early study, and the following revised structure of the pentasaccharide repeating unit was established: where approximately 70% glcnac residues bear an o-acetyl group at position 3. the o-antigen of escherichia coli o112ac was found to have the same ...200818308298
nlrx1: friend or foe? 200818311173
ipgb1 and ipgb2, two homologous effectors secreted via the mxi-spa type iii secretion apparatus, cooperate to mediate polarized cell invasion and inflammatory potential of shigella flexenri.type iii secretion systems (t3ss) are present in many pathogenic gram-negative bacteria and mediate the translocation of bacterial effector proteins into host cells. here, we report the phenotypic characterization of s. flexneri ipgb1 and ipgb2 mutants, in which the genes encoding the ipgb1 and ipgb2 effectors have been inactivated, either independently or simultaneously. like ipgb1, we found that ipgb2 is secreted by the t3ss and its secretion requires the spa15 chaperone. upon infection of sem ...200818316224
delivery of biologically active anti-inflammatory cytokines il-10 and il-1ra in vivo by the shigella type iii secretion apparatus.pathogenicity of many gram-negative bacteria relies on a type iii secretion (t3s) apparatus, which is used for delivery of bacterial effectors into the host cell cytoplasm allowing the bacteria to manipulate host cell cytoskeleton network as well as to interfere with intracellular signaling pathways. in this study, we investigated the potential of the shigella flexneri t3sa as an in vivo delivery system for biologically active molecules such as cytokines. the anti-inflammatory cytokines il-10 an ...200818322242
impact of infections and normal flora in nonhuman primates on drug development.preclinical safety studies that are required for the marketing approval of a pharmaceutical include single and repeat dose studies in rodent and nonrodent species. the use of nonhuman primates (nhps), primarily macaques, as the nonrodent species has increased in recent years, in part due to the increase in development of biopharmaceuticals and immunomodulatory agents. depending on the source of the macaques, they may vary in genetic background, normal flora, and/or the incidence of preexisting p ...200818323580
pyrosequencing analysis of the gyrb gene to differentiate bacteria responsible for diarrheal diseases.pathogens causing acute diarrhea include a large variety of species from enterobacteriaceae and vibrionaceae. a method based on pyrosequencing was used here to differentiate bacteria commonly associated with diarrhea in china; the method is targeted to a partial amplicon of the gyrb gene, which encodes the b subunit of dna gyrase. twenty-eight specific polymorphic positions were identified from sequence alignment of a large sequence dataset and targeted using 17 sequencing primers. of 95 isolate ...200818324428
insecticidal properties and microbial contaminants in a spodoptera exigua multiple nucleopolyhedrovirus (baculoviridae) formulation stored at different temperatures.the spodoptera exigua (hübner) multiple nucleopolyhedrovirus (semnpv) is currently being tested as a biological insecticide for use in greenhouse crops in southern spain. we performed a study in which semipurified semnpv occlusion bodies (obs) were formulated in phosphate-buffered saline, ph 6.5, with 5% (vol:vol) glycerol and 0.15% (wt:vol) sorbic acid, and they were stored at -20, 4, or 25 degrees c during 18 mo. initial aerobic counts (+/-se) averaged 1.4 (+/-0.17) x 10(7) colony-forming unit ...200818330114
subversion of actin dynamics by espm effectors of attaching and effacing bacterial pathogens.rho gtpases are common targets of bacterial toxins and type iii secretion system effectors. ipgb1 and ipgb2 of shigella and map of enteropathogenic (epec) and enterohemorrhagic (ehec) escherichia coli were recently grouped together on the basis that they share a conserved wxxxe motif. in this study, we characterized six wxxxe effectors from attaching and effacing pathogens: trca and espm1 of epec strain b171, espm1 and espm2 of ehec strain sakai and espm2 and espm3 of citrobacter rodentium. we s ...200818331467
prevalence of gastrointestinal bacterial pathogens in a population of zoo animals.faecal prevalence of gastrointestinal bacterial pathogens, including campylobacter, escherichia coli o157:h7, salmonella, shigella, yersinia, as well as arcobacter, were examined in 317 faecal specimens from 44 animal species in belfast zoological gardens, during july-september 2006. thermophilic campylobacters including campylobacter jejuni, campylobacter coli and campylobacter lari, were the most frequently isolated pathogens, where members of this genus were isolated from 11 animal species (1 ...200818331520
cold shock exoribonuclease r (vacb) is involved in aeromonas hydrophila pathogenesis.in this study, we cloned and sequenced a virulence-associated gene (vacb) from a clinical isolate ssu of aeromonas hydrophila. we identified this gene based on our recently annotated genome sequence of the environmental isolate atcc 7966(t) of a. hydrophila and the vacb gene of shigella flexneri. the a. hydrophila vacb protein contained 798 amino acid residues, had a molecular mass of 90.5 kda, and exhibited an exoribonuclease (rnase r) activity. the rnase r of a. hydrophila was a cold-shock pro ...200818344363
maturation of paneth cells induces the refractory state of newborn mice to shigella infection.the intestinal tract of adult mice is naturally resistant to infection by shigella, the causative agent of bacillary dysentery in humans. conversely, newborn mice are highly susceptible to intragastric shigella infection and develop inflammatory lesions of the jejunal mucosa, very similar to those observed in the colon of dysenteric patients. however, the susceptibility period is short and one week after birth, animals have acquired a status of resistance characteristic of adult animals. to iden ...200818354217
high rate of resistance to locally used antibiotics among enteric bacteria from children in northern ghana.information on antimicrobial susceptibility of bacterial pathogens is scarce in resource-poor settings. we determined the susceptibility of bacterial enteric pathogens and faecal escherichia coli isolates obtained from children in urban tamale, northern ghana, to antibiotics widely used in the that area [ampicillin or amoxicillin, trimethoprim/sulfamethoxazole (sxt) and chloramphenicol] and to alternative drugs.200818356156
differential expression of ompc and ompf in multidrug-resistant shigella dysenteriae and shigella flexneri by aqueous extract of aegle marmelos, altering its susceptibility toward beta-lactam antibiotics.steadily increasing resistance among shigella to beta-lactams, aminoglycosides, and tetracycline has compromised the utility of these commonly used antimicrobial agents. also, undesirable side effects of certain antibiotics have triggered immense interest in search of alternative therapies using medicinal plants. one such medicinal plant used since ancient times to cure diarrhea is aegle marmelos. the present study exemplifies the susceptibility of beta-lactam-resistant shigella dysenteriae and ...200818358664
differential regulation by magnesium of the two msbb paralogs of shigella flexneri.shigella flexneri, a gram-negative enteric pathogen, is unusual in that it contains two nonredundant paralogous genes that encode the myristoyl transferase msbb (lpxm) that catalyzes the final step in the synthesis of the lipid a moiety of lipopolysaccharide. msbb1 is encoded on the chromosome, and msbb2 is encoded on the large virulence plasmid present in all pathogenic shigellae. we demonstrate that myristoyl transferase activity due to msbb2 is detected in limited magnesium medium, but not in ...200818359815
ctx-m-3 type beta-lactamase producing shigella sonnei isolates from pediatric bacillary dysentery cases.in this study, 153 clinical isolates of shigella were screened for extended-spectrum beta-lactamase (esbl) production by double-disk synergy test. after being confirmed by the combined disk-test and inhibitor-combined e-test strips, all positive isolates were tested for the bla gene by pcr and the enzymes by isoelectric focusing. dna sequencing of pcr products revealed that five shigella sonnei isolates had ctx-m-3 type esbl enzymes. all of them were resistant to ampicillin, sulfamethoxazole and ...200818362404
[antigenic polysaccharides of bacteria: 40. the structures of o-specific polysaccharides from shigella dysenteriae types 3 and 9 and s. boydii type 4 revised by nmr spectroscopy].the reported structures of o-specific polysaccharides from three standard strains of shigella bacteria were corrected by modern nmr techniques. the revisions concerned the configuration of the o-glycoside linkage (s. dysenteriae type 3, structure 1), the positions of monosaccharide residue glycosylation and acetylation by pyruvic acid (s. dysenteriae type 9, structure 2), and the attachment position of the side monosaccharide chain (s. boydii type 4, structure 3) [struxture in text].200818365747
contamination of a blood culture with shigella sonnei. 200818371521
analysis of rho-gtpase mimicry by a family of bacterial type iii effector proteins.microbial pathogens may hijack the actin cytoskeleton machinery to facilitate actin-based motility, cellular invasion, and intracellular trafficking through the endocytic pathway. of particular interest has been a large class of virulence factors collectively termed the type iii "effector" proteins. following contact with a eukaryotic cell, gram-negative bacterial pathogens employ a dedicated protein secretion apparatus termed type iii to translocate effector proteins into the cellular cytoplasm ...200818374161
coiled-coil regions play a role in the function of the shigella flexneri o-antigen chain length regulator wzzphs2.regulation of the length of the o-antigen (oag) chain attached to lps in shigella flexneri is important for virulence and is dependent on the inner-membrane protein wzz. a lack of high-resolution structural data for wzz has hampered efforts so far to correlate mutations affecting function of wzz with structure and describe a mechanism for chain length regulation. here we have used secondary structure prediction to show that the periplasmic domain of the wzz(phs2) protein has three regions of sig ...200818375803
ospf directly attenuates the activity of extracellular signal-regulated kinase during invasion by shigella flexneri in human dendritic cells.shigella spp., gram-negative pathogenic bacteria, deliver various effector molecules into the host cell cytoplasm through their type iii secretion system to facilitate their invasive process and control the host innate immune responses. although the function of these effectors is well characterized in epithelial cells during shigella infection, it has not been elucidated in the dendritic cell (dc), a major antigen presenting cell playing an important role in the initiation of immune responses. i ...200818378312
synthesis, characterization and antibacterial activity of cobalt(iii) complexes with pyridine-amide ligands.the ligands 2-(n-(x-pyridyl)carbamoyl)pyridine (x=2, 3 or 4 for hl1-hl3, respectively) and 2,6-bis(n-(y-pyridyl)carbamoyl)pyridine (y=2, 3 or 4 for h2l4-h2l6, respectively) in their mono- and di-deprotonated forms have been used to synthesize kinetically stable cobalt(iii) compounds [co(l1-3)3] (1-3) and na[co(l4-6)2] (4-6), respectively. the co(iii) ion is in octahedral environment and is surrounded by three bidentate ligands in complexes 1-3 and two tridentate ligands in complexes 4-6. ligands ...200817959275
the pattern-recognition molecule nod1 is localized at the plasma membrane at sites of bacterial interaction.the pattern-recognition molecule nod1 is a critical sensor for bacterial derived diaminopimelic acid-containing peptidoglycan fragments which induces innate immune responses in epithelial cells. here we report the subcellular localization of this protein in human epithelial cells. nod1 is localized in the cytosol and at the plasma membrane in human cells. this membrane association is dependent on the integrity of the protein, on its signalling capacity and on an intact actin cytoskeleton. signal ...200817970764
evaluating burkholderia pseudomallei bip proteins as vaccines and bip antibodies as detection agents.burkholderia pseudomallei is a biothreat agent and an important natural pathogen, causing melioidosis in humans and animals. a type iii secretion system (ttss-3) has been shown to be critical for virulence. because ttss components from other pathogens have been used successfully as diagnostic agents and as experimental vaccines, it was investigated whether this was the case for bipb, bipc and bipd, components of b. pseudomallei's ttss-3. the sequences of bipb, bipc and bipd were found to be high ...200817995960
bacterial and fungal infections among diagnostic laboratory workers: evaluating the risks.accidental infections acquired in the laboratory environment are not reportable in a formal forum outside the institution, and therefore, there is little opportunity to evaluate such occurrences and learn from them. we evaluated voluntary responses from 88 facilities, 53 large hospitals (>200 beds) or academic institutions, 32 smaller facilities (<200 beds), and 3 national reference diagnostic laboratories. thirty-eight of the laboratories (43%), 15 large and 23 small facilities, reported no kno ...200817997259
enteropathogen resource integration center (eric): bioinformatics support for research on biodefense-relevant enterobacteria.eric, the enteropathogen resource integration center (www.ericbrc.org), is a new web portal serving as a rich source of information about enterobacteria on the niaid established list of select agents related to biodefense-diarrheagenic escherichia coli, shigella spp., salmonella spp., yersinia enterocolitica and yersinia pestis. more than 30 genomes have been completely sequenced, many more exist in draft form and additional projects are underway. these organisms are increasingly the focus of st ...200817999997
priming of cd4+ t cells with porin of shigella dysenteriae activates the cells toward type 1 polarization.macrophages treated with porin of shigella dysenteriae were potent stimulators of naive t(h) cells since the porin-pulsed macrophages strongly proliferated the t cells and up-regulated the activation molecules cd69 and cd25 on cd4(+) t cells in allogeneic mixed leukocyte reaction. immunization of c57bl/6 mice with porin selectively induced the intracellular expression and release of ifn-gamma and had no effect on il-4 expression. in parallel to the predominant release of the t(h)1 cytokine ifn-g ...200818003602
shiga toxin 1 induces apoptosis through the endoplasmic reticulum stress response in human monocytic cells.shiga toxins (stxs) expressed by the enteric pathogens shigella dysenteriae 1 and enterohaemorrhagic escherichia coli are potent protein synthesis inhibitors. shiga toxins have also been shown to induce apoptosis in epithelial, endothelial and monocytic cells. the precise relationship between protein synthesis inhibition and induction of apoptosis is not known. we show that stimulation of the myelogenous leukaemia cell line thp-1 with purified stx1 induced the endoplasmic reticulum (er) stress r ...200818005243
the nlee/ospz family of effector proteins is required for polymorphonuclear transepithelial migration, a characteristic shared by enteropathogenic escherichia coli and shigella flexneri infections.enteropathogenic escherichia coli (epec) and shigella flexneri are human host-specific pathogens that infect intestinal epithelial cells. however, each bacterial species employs a different infection strategy within this environmental niche. epec attaches to the apical surface of small intestine enterocytes, causing microvillus effacement and rearrangement of the host cell cytoskeleton beneath adherent bacteria. in contrast, s. flexneri invades the large intestine epithelium at the basolateral m ...200817984206
contribution of the sitabcd, mnth, and feob metal transporters to the virulence of avian pathogenic escherichia coli o78 strain chi7122.the roles of sitabcd, mnth, and feob metal transporters in the virulence of avian pathogenic escherichia coli (apec) o78 strain chi7122 were assessed using isogenic mutants in chicken infection models. in a single-strain infection model, compared to chi7122, the deltasit strain demonstrated reduced colonization of the lungs, liver, and spleen. complementation of the deltasit strain restored virulence. in a coinfection model, compared to the virulent apec strain, the deltasit strain demonstrated ...200818025097
muramylpeptide shedding modulates cell sensing of shigella flexneri.bacterial infections trigger the activation of innate immunity through the interaction of pathogen-associated molecular patterns (pamps) with pattern recognition molecules (prms). the nucleotide-binding oligomerization domain (nod) proteins are intracellular prms that recognize muramylpeptides contained in peptidoglycan (pgn) of bacteria. it is still unclear how nod1 physically interacts with pgn, a structure internal to the gram-negative bacterial envelope. to contribute to the understanding of ...200818042252
the versatility of shigella effectors.when shigella infect the intestinal epithelium, they deliver several effectors through the type iii secretion system (t3ss) into the surrounding space and directly into the host-cell cytoplasm, where they can mimic and usurp host cellular functions or subvert host-cell signalling pathways and the immune response. although bacterial strategies and mechanisms of infection vary greatly, recent studies of shigella effectors have revealed that shigella possess a highly evolved strategy for infection.200818059288
saccharomyces boulardii interferes with shigella pathogenesis by postinvasion signaling events.saccharomyces boulardii is gaining in popularity as a treatment for a variety of diarrheal diseases as well as inflammatory bowel disease. this study was designed to examine the effect of this yeast on infection by shigella flexneri, a highly infectious and human host-adapted enteric pathogen. we investigated key interactions between the bacteria and host cells in the presence of the yeast in addition to a number of host responses including proinflammatory events and markers. although the presen ...200818032477
activities of the frog skin peptide, ascaphin-8 and its lysine-substituted analogs against clinical isolates of extended-spectrum beta-lactamase (esbl) producing bacteria.extended-spectrum beta-lactamase (esbl)-producing gram-negative bacteria are becoming increasingly prevalent and their antibiotic resistance necessitates novel therapeutic intervention. ascaphin-8 is a cationic alpha-helical peptide that shows broad-spectrum antibacterial activity but is also toxic to human erythrocytes (lc(50)= 55 microm). this study assesses the activity of ascaphin-8, and a series of l-lysine-substituted analogs, against a range of clinical isolates of esbl-producing bacteria ...200818068868
quinolone resistance among shigella spp. isolated from travellers returning from india.among 200 isolates of shigella from patients with travellers' diarrhoea, 12 isolates (four isolated in 1995-2000 and eight in 2001-2004) exhibited quinolone resistance. nine of these isolates originated from india. these resistant isolates had at least one amino-acid substitution in gyra. quinolone resistance is increasing in shigella spp. causing travellers' diarrhoea, and particularly among isolates causing diarrhoea in travellers returning from india.200818076667
isolation and purification of enterocin e-760 with broad antimicrobial activity against gram-positive and gram-negative bacteria.strain nrrl b-30745, isolated from chicken ceca and identified as enterococcus durans, enterococcus faecium, or enterococcus hirae, was initially identified as antagonistic to campylobacter jejuni. the isolate produced a 5,362-da bacteriocin (enterocin) that inhibits the growth of salmonella enterica serovar enteritidis, s. enterica serovar choleraesuis, s. enterica serovar typhimurium, s. enterica serovar gallinarum, escherichia coli o157:h7, yersinia enterocolitica, citrobacter freundii, klebs ...200818086839
systemic pharmacokinetics of rifaximin in volunteers with shigellosis.rifaximin is an oral antibiotic indicated for treatment of traveler's diarrhea. rifaximin pharmacokinetics were evaluated in individuals challenged with shigella flexneri. peak plasma rifaximin concentrations were low after nine consecutive doses, and no accumulation was observed. rifaximin serum levels were minimal and similar to those previously reported in studies of healthy volunteers.200818086855
antimicrobial activity of an endophytic xylaria sp.yx-28 and identification of its antimicrobial compound 7-amino-4-methylcoumarin.an endophytic xylaria sp., having broad antimicrobial activity, was isolated and characterized from ginkgo biloba l. from the culture extracts of this fungus, a bioactive compound p3 was isolated by bioactivity-guided fractionation and identified as 7-amino-4-methylcoumarin by nuclear magnetic resonance, infrared, and mass spectrometry spectral data. the compound showed strong antibacterial and antifungal activities in vitro against staphylococcus aureus [minimal inhibitory concentrations (mic) ...200818092158
phenotypic and molecular characterization of tem-116 extended-spectrum beta-lactamase produced by a shigella flexneri clinical isolate from chickens.extended-spectrum beta-lactamases (esbls) produced by a clinical isolate of shigella flexneri from chickens were detected with confirmatory phenotypic tests of the clinical and laboratory standards institute, and minimum inhibitory concentrations of several antibacterial drugs against the isolate were determined by the twofold dilution method. the genotype and subtype of the esbl-producing s. flexneri isolate were identified by pcr amplifying of esbl genes and dna sequencing analysis. the result ...200818093137
bacterial reduction of selenate to elemental selenium utilizing molasses as a carbon source.selecting an inexpensive and effective organic carbon source is the key to reducing the cost in selenium (se) remediation. five bacteria were screened based on their ability in using molasses as an organic carbon source to reduce selenate [se(vi)] in drainage water. efficiency of se removal differed in the molasses-added drainage water containing different bacteria, with an order of enterobacter taylorae>pantoea sp. sss2>klebsiella sp. wrs2>citerobacter freundii>shigella sp. dw2. by using e. tay ...200817512724
emerging resistance to newer antimicrobial agents among shigella isolated from finnish foreign travellers.in finland, most cases of shigellosis are related to travel abroad. antimicrobial drug resistance of 1814 shigella strains isolated from finnish patients during 1990-2005 was studied using discs of 12 antimicrobial agents. since 2000, the e-test has been performed to determine ciprofloxacin minimum inhibitory concentrations of nalidixic acid-resistant isolates. the proportion of multi-resistant strains (resistant to >or =4 antimicrobials) was highest among isolates from china and india, but is i ...200817578602
risk areas and neighborhood-level risk factors for shigella dysenteriae 1 and shigella flexneri.annually, there are 165 million cases of shigellosis resulting in 1.1 million deaths in the developing world. two species of the causative agent, shigella dysenteriae 1 and shigella flexneri, are responsible for acute diarrheal illness. vaccines are being developed against both but many questions remain about the disease burden, distribution of species in space and time, and community-level risk factors. this study answers two questions. what are the differences in neighborhood-level risk factor ...200817602851
detection of the causative agent of furunculusis, aeromonas salmonicida in salmonids of the krka river.in this paper we describe the bacterial community associated with salmonids from the krka river. diversity analysis demonstrated that majority of the recovered bacteria were related to aeromonadaceae group. bacterial analysis also revealed the presence of shigella spp. and pseudomonas fluorescens. isolation of aeromonas salmonicida from trout, presents first isolation of this bacteria croatian rivers.200817624808
part ii. analysis of data gaps pertaining to shigella infections in low and medium human development index countries, 1984-2005.the global incidence of shigella infection has been estimated at 80-165 million episodes annually, with 99% of episodes occurring in the developing world. to identify contemporary gaps in the understanding of the global epidemiology of shigellosis, we conducted a review of the english-language scientific literature from 1984 to 2005, restricting the search to low and medium human development countries. our review yielded 11 population-based studies of shigella burden from seven countries. no pop ...200817686195
drastic decrease of salmonella enteritidis isolated from humans in belgium in 2005, shift in phage types and influence on foodborne outbreaks.in belgium, non-typhoidal salmonellosis and campylobacteriosis are the two most frequently reported foodborne illnesses. during 2005, a 71% decrease of salmonella enteritidis infections compared with the average annual number cases in the period 2000-2004 was recorded by the belgian national reference centre for salmonella and shigella. after the peak of 1999, the total number of salmonellosis cases decreased gradually, with the exception of 2003 when an increase was again recorded due to the ri ...200817645812
isolation and antibiotic susceptibility of salmonella and shigella strains isolated from children in gaza, palestine from 1999 to 2006.diarrhea and acute gastroenteritis are among the leading causes of illnesses and death in infants and children throughout the world, especially in developing countries, globally, salmonella and shigella remain the major contributors to acute enteric infections and diarrhea.200817854424
role of shigella infection in endometriosis: a novel hypothesis.endometriosis is the presence of endometrial cells and stroma at ectopic sites outside the uterine cavity. the natural history of endometriosis is uncertain, its etiology unknown, the clinical presentation inconsistent, diagnosis difficult and the treatment poorly standardized. it causes significant morbidity due to pelvic pain and infertility among 15-25% of women during their reproductive age. the benign disease causes peritoneal inflammation, fibrosis, adhesions and ovarian cysts but displays ...200817888583
clostridium difficile: an under-recognized cause of reactive arthritis?reactive arthritis usually presents as a sterile, inflammatory, asymmetric oligoarthritis, affecting large lower extremity joints. extra-articular features (conjunctivitis, uveitis, enthesopathy, urethritis, balanitis, keratoderma blenorrhagicum) may occur. common causes of enteric reactive arthritis are preceding infections attributable to salmonella, shigella, campylobacter, and yersinia. in contrast, clostridium difficile is an uncommon cause of reactive arthritis, with only approximately 40 ...200817902012
identification of newly recognized serotype 1c as the most prevalent shigella flexneri serotype in northern rural vietnam.we investigated the identity of 37 shigella flexneri strains that had previously been isolated from northern rural vietnam (son tay province) and described as untypable. twenty-four isolates reacted with masf 1c, a monoclonal antibody specific for s. flexneri serotype 1c. a further ten untypable isolates were found to be rough mutants (no longer expressing o-antigen) that were derived from serotype 1c strains. pulsed-field gel electrophoresis demonstrated that these strains consisted of many dif ...200817922932
development of a tripartite vector system for live oral immunization using a gram-negative probiotic carrier.the mucosa represents the primary target site and thus the first barrier for most microbial pathogens. nevertheless, nearly all present-day vaccines are applied by an invasive route, target the systemic immune system, and do not confer efficient mucosal protection. currently, mucosal immunity can only be achieved by the delivery of antigens via the mucosal route. therefore, multiple efforts are under way to develop mucosal vaccines and particularly live oral vaccines as these would confer consid ...200817936683
a role for nod-like receptors in autophagy induced by shigella infection.shigella infection, the cause of bacillary dysentery, induces caspase-1 activation and cell death in macrophages, but the precise mechanisms remain poorly understood. in our recent study, we presented evidence that caspase-1 activation and il-1beta processing induced by shigella are mediated through ipaf, a cytosolic pattern-recognition receptor of the nucleotide-binding oligomerization domain (nod)-like receptor (nlr) family and the adaptor protein apoptosis-associated speck-like protein contai ...200817932464
[hemolytic and uremic syndrome in the child].hemolytic and uremic syndrome (hus) is characterized by the association of hemolytic anemia with sckizocytes, thrombopenia and renal involvement secondary to thrombotic microangiopathy. the typical form is the most frequent in children occurring after an episode of diarrhea caused by escherichia coli. other microorganisms may be responsible for hus such as shigella dysenteriae or streptococcus pneumoniae. acute renal failure is reversible in most cases, but long-term renal sequelae are seen in o ...200817964233
antimicrobial activity of some macrophytes from lake manzalah (egypt).the antimicrobial activities of aqueous and organic solvents (chloroform, ethanol and methanol) extracts of four plants ceratophyllum demersum l., eichhornia crassipes, potamogeton crispus and potamogeton pectinatus were tested in vitro against seventeen different microorganisms including gram-positive and gram-negative bacteria and fungi. nine of these identified organisms were obtained from different sources, bacillus subtilis 1020, bacillus cereus 1080, staphylococcus aureus, erwinia carotovo ...200819205264
shigella and salmonella serogroups and their antibiotic susceptibility patterns in ethiopia.in this study, the serogroup and susceptibility patterns of shigella and salmonella spp. isolated from stool cultures were determined using standard laboratory procedures. among the 76 shigella isolates serogroup b (sh. flexeneri) was the most prevalent species (54.0%) and among the 37 salmonella strains serogroup b was also the most prevalent (81.1%). antibiograms of shigella and salmonella spp. showed 100% resistance to erythromycin and high resistance rates (> or = 75%) to ampicillin, cephalo ...200819166157
in silico comparison of simple sequence repeats in high nucleotides-rich genomes of microorganism.this study determined the distribution of a specific group of simple sequence repeats (ssrs), in genome sequences of 7 chromosomes (shigella flexneri 2a str 301 and 2457 t, shigella sonnei, e. coli k12, m. tuberculosis, m. leprae and s. saprophytycus) have downloaded from the genbank database for identifying abundance, distribution and composition of ssrs. the data obtained in the present study show that: (i) tandem repeats are widely distributed throughout the genomes. (ii) ssrs are differentia ...200819137845
oral immunization: an update.oral immunization with vaccines against intestinal infectious diseases has been extensively explored for several decades. despite the immunologic and economic rationale behind oral immunization, only a few mucosal vaccines are available for the prevention of mucosal infections. here, we summarize the current status of such vaccines, with a focus on intestinal infectious diseases, describe alternative approaches, and analyze advantages and difficulties encountered with a broad implementation of t ...200819122521
genomic analysis of bacteriophage epsilon 34 of salmonella enterica serovar anatum (15+).the presence of prophages has been an important variable in genetic exchange and divergence in most bacteria. this study reports the determination of the genomic sequence of salmonella phage epsilon 34, a temperate bacteriophage that was important in the early study of prophages that modify their hosts' cell surface and is of a type (p22-like) that is common in salmonella genomes.200819091116
analysis of plasmid genes by phylogenetic profiling and visualization of homology relationships using blast2network.phylogenetic methods are well-established bioinformatic tools for sequence analysis, allowing to describe the non-independencies of sequences because of their common ancestor. however, the evolutionary profiles of bacterial genes are often complicated by hidden paralogy and extensive and/or (multiple) horizontal gene transfer (hgt) events which make bifurcating trees often inappropriate. in this context, plasmid sequences are paradigms of network-like relationships characterizing the evolution o ...200819099604
[detection and identification of seven clinical common pathogenic bacteria by oligonucleotide microarray].using 16s rdna and 23s rdna genes as the target sequences to develop a system based on oligonucleotide microarray and to detect the seven clinical pathogenic bacteria, commonly seen.200819103121
water-related diseases outbreaks reported in italy.water related disease outbreak (wrdo) statistics in italy from 1998 to 2005 have been discussed in this paper. the true incidence of wrdo is not reflected in the national surveillance system (nss), although this study has provided information on pathogens associated to different water sources, incidence in regions and inadequacy of regulations. 192 outbreaks and 2546 cases of wrd were reported to the nss, an average of 318 cases per year. cases were associated to shellfish (58.79%), drinking wat ...200819108563
shigella from humans in thailand during 1993 to 2006: spatial-time trends in species and serotype distribution.in thailand during 1993-2006, a total of 9063 shigella isolates from different medical centers were serotyped and trends over time and spatial clustering analyzed. of 3583 cases with age information, 1315 (37%) cases were from children between 0 and 4 years and 684 (19%) from children between 5 and 8 years. most infections were recorded during 1993-1994 (> 1500 per year), decreasing to < 200 in 2006. the relative species distribution also changed. during 1993-1994, shigella flexneri accounted fo ...200819086804
[structures of o-polysaccharides from two shigella dysenteriae type 8 strains].the structure of the o-polysaccharide (o-antigen) from shigella dysenteriae type 8 bacteria (strain 599) was corrected using modern nmr techniques (structure 1). the revisions concerned the position of the glc residue (in the main, but not the side, chain), the site of its substitution, and the configuration of the o-glycoside linkage of the glcnac residue. the s. dysenteriae type 8 bacterium (strain g1221), the second investigated representative, was found to produce another structural variant ...200819088755
characterization of shigella spp. by antimicrobial resistance and pcr detection of ipa genes in an infantile population from porto velho (western amazon region), brazil.the incidence of shigella spp. was assessed in 877 infants from the public hospital in rondônia (western amazon region, brazil) where shigella represents the fourth cause of diarrhea. twenty-five isolates were identified: 18 were shigella flexneri, three shigella sonnei, three shigella boydii and one shigella dysenteriae. with the exception of s. dysenteriae, all shigella spp. isolated from children with diarrhea acquired multiple antibiotic resistances. pcr detection of ipa virulence genes and ...200819057826
increased isolation and characterization of shigella sonnei obtained from hospitalized children in tehran, iran.shigella flexneri has been the most frequent cause of shigellosis in children in iran. to evaluate the changes in frequency of serogroups, 302 shigella species were isolated in 2003 from hospitalized children, aged less than 12 years, with acute diarrhoea in tehran, iran. the number of collected s. sonnei, s. flexneri, s. boydii, and s. dysenteriae isolates was 178 (58.9%), 110 (37.4%), 10 (3.3%), and 4 (1.3%) respectively. most (94%) s. sonnei isolates were resistant to co-trimoxazole. they wer ...200819069621
prevalence of bacteria and intestinal parasites among food-handlers in gondar town, northwest ethiopia.food-handlers with poor personal hygiene working in food-service establishments could be potential sources of infection due to pathogenic organisms. the study was undertaken to determine the prevalence of bacteria and intestinal parasites among 127 food-handlers working in the cafeterias of the university of gondar and the gondar teachers training college, gondar, ethiopia. fingernail contents of both the hands and stool specimens were collected from all the 127 food-handlers. the samples were e ...200819069624
prevalence of shigella serogroups and their antimicrobial resistance patterns in southern trinidad.the serogroup distribution and antimicrobial susceptibility patterns of shigella isolates obtained from stool specimens of persons with acute diarrhoea in community-based studies from southern trinidad during 1997-2006 were reviewed. of the 5,187 stool specimens, 392 (8%) were positive for shigella organisms. from these 392 isolates, 88.8% were recovered from children aged >0-10 year(s). shigella sonnei was the most frequently-isolated serogroup (75%), followed by s. flexneri (19%), s. boydii (4 ...200819069625
gef-h1 mediated control of nod1 dependent nf-kappab activation by shigella effectors.shigella flexneri has evolved the ability to modify host cell function with intracellular active effectors to overcome the intestinal barrier. the detection of these microbial effectors and the initiation of innate immune responses are critical for rapid mucosal defense activation. the guanine nucleotide exchange factor h1 (gef-h1) mediates rhoa activation required for cell invasion by the enteroinvasive pathogen shigella flexneri. surprisingly, gef-h1 is requisite for nf-kappab activation in re ...200819043560
outbreaks where food workers have been implicated in the spread of foodborne disease. part 4. infective doses and pathogen carriage.in this article, the fourth in a series reviewing the role of food workers in foodborne outbreaks, background information on the presence of enteric pathogens in the community, the numbers of organisms required to initiate an infection, and the length of carriage are presented. although workers have been implicated in outbreaks, they were not always aware of their infections, either because they were in the prodromic phase before symptoms began or because they were asymptomatic carriers. pathoge ...200819044283
the acrab-tolc pump is involved in multidrug resistance in clinical shigella flexneri isolates.the two multiple-antibiotic resistance (mar) phenotypes (n = 8, respectively) and susceptible isolates (n = 4) of shigella flexneri from china were characterized involving the efflux pump acrab-tolc. the accumulation of ciprofloxacin, acrab-tolc pcr, and levels of mrna with northern blots were performed in three groups. sequencing of acrab-tolc was performed in selected isolates. an efflux inhibition was performed with phe-arg-beta-naphthylamide. the accumulation of ciprofloxacin at steady state ...200819035770
biometric fingerprinting for visa application: device and procedure are risk factors for infection transmission.biometric fingerprint identity verification is currently introduced in visa application and entry screening at border control. the system implies physical contact between the skin and the surface of the fingerprint-capturing and reading devices.200819006507
functional nanoparticle-based proteomic strategies for characterization of pathogenic bacteria.although matrix-assisted laser desorption/ionization mass spectrometry (maldi ms) can be employed to rapidly characterize pathogenic bacteria, bacterial cultures are generally required to obtain sufficient quantities of the bacterial cells prior to maldi ms analysis. if this time-consuming step could be eliminated, the length of time required for identification of bacterial strains would be greatly reduced. in this paper, we propose an effective means of rapidly identifying bacteria--one that do ...200819007241
spa32 interaction with the inner-membrane spa40 component of the type iii secretion system of shigella flexneri is required for the control of the needle length by a molecular tape measure mechanism.the effectors of enterocyte invasion by shigella are dependent on a type iii secretion system that contains a needle whose length average does not exceed 50 nm. previously, we reported that spa32 is required for needle length control as well as to switch substrate specificity from mxih to ipa proteins secretion. to identify functional domains of spa32, 11 truncated variants were constructed and analysed for their capacity (i) to control the needle's length; (ii) to secrete the ipa proteins; and ...200819019157
is escherichia coli o157:h7 a common pathogen in children with bloody diarrhea in shiraz, iran?escherichia coli (e. coli) o157:h7 is a common cause of bloody diarrhea in developed countries. the aim of this study was to determine whether e. coli o157:h7 is a possible pathogen of bloody diarrhea in southern iran. out of 719 children with diarrhea, 243 (34%) patients with positive occult blood took part in our study. the polyclonal antibody test and polymerase chain reaction (pcr) were used to identify e. coli o157:h7. stool cultures showed enteropathogens in 107 patients (44%). shigella (3 ...200819014048
[antibiotic resistance of bacterial strains in paediatric infections: there are resistance and resistance!].isolation of a bacterial strain at the infectious site and determination of the susceptibility profile may help to guide appropriate antibiotic treatment. however technical difficulties justify interpretative reading to recognize interfering resistance mechanisms from resistance phenotypes. the aim of this article is to give some examples showing interpretative reading of routine sensitivity test data.200819000854
structure of the shigella t3ss effector ipah defines a new class of e3 ubiquitin ligases.ipah proteins are e3 ubiquitin ligases delivered by the type iii secretion apparatus into host cells upon infection of humans by the gram-negative pathogen shigella flexneri. these proteins comprise a variable leucine-rich repeat-containing n-terminal domain and a conserved c-terminal domain harboring an invariant cysteine residue that is crucial for activity. ipah homologs are encoded by diverse animal and plant pathogens. here we demonstrate that the ipah c-terminal domain carries the catalyti ...200818997778
structure of a shigella effector reveals a new class of ubiquitin ligases.bacterial pathogens have evolved effector proteins with ubiquitin e3 ligase activities through structural mimicking. here we report the crystal structure of the shigella flexneri type iii effector ipah3, a member of the leucine-rich repeat (lrr)-containing bacterial e3 family. the lrr domain is structurally similar to yersinia pestis yopm and potentially binds to substrates. the structure of the c-terminal e3 domain differs from the typical ring- and hect-type e3s. ipah3 synthesizes a lys48-link ...200818997779
a pilot sheds light on secretin assembly. 200818940600
structural characterization of the type-iii pilot-secretin complex from shigella flexneri.assembly of the type-iii secretion apparatus, which translocates proteins through both membranes of gram-negative bacterial pathogens into host cells, requires the formation of an integral outer-membrane secretin ring. typically, a small lipidated pilot protein is necessary for the stabilization and localization of this ring. using nmr spectroscopy, we demonstrate that the c-terminal residues 553-570 of the shigella flexneri secretin mxid encompass the minimal binding domain for its cognate pilo ...200818940609
antimicrobial activity of endemic crataegus tanacetifolia (lam.) pers and observation of the inhibition effect on bacterial cells.up to now an increasing number of antibiotic-resistant bacteria have been reported and thus new natural therapeutic agents are needed in order to eradicate these pathogens. through the discovery of plants such as crataegus tanacetifolia (lam.) pers that have antimicrobial activity, it will be possible to discover new natural drugs serving as chemotherapeutic agents for the treatment of nosocomial pathogens and take these antibiotic-resistant bacteria under control. the objective of the present s ...200818946875
detection of protozoan and bacterial pathogens of public health importance in faeces of corvus spp. (large-billed crow).parasites and bacteria are reported in the faeces of birds in the current study. fresh faecal samples of the large-billed crow (corvus spp.) were collected from the study site at bangsar, an urban setting in kuala lumpur, malaysia. these samples were transported to laboratory and analysed for parasites and bacteria. pre-prepared xld agar plates were used for culturing the bacteria in the laboratory. using the api 20etm test strips, 9 different species of bacteria were identified belonging to the ...200818948884
analysis of immune responses and serological cross reactivities among vibrio cholerae o1, shigella flexneri 2a and haemophilus influenzae b.antigenic determinants expressed on the bacterial cell surface are of importance in the serological characterization and microbiological diagnosis. the bacterial strains carrying these identical or similar antigenic epitopes might react with antibodies produced against other strains. in this study, strong immunogenicity and antigenic cross reactivity were demonstrated among v. cholerae o1, s. flexnerii 2a and h. influenzae b surface components. the enzyme linked immunosorbent assay (elisa) resul ...200818954564
the elucidation of the structure of the core part of the lps from plesiomonas shigelloides serotype o17 expressing o-polysaccharide chain identical to the shigella sonnei o-chain.plesiomonas shigelloides o17 lps contains the same o-antigenic polysaccharide chain as a causative agent of dysentery, shigella sonnei. this polysaccharide can be used as a component of a vaccine against dysentery. core part of the p. shigelloides o17 lps was studied using nmr and mass spectrometry and the following structure was proposed: [structure : see text]. significant similarity of the p. shigelloides o17 lps core with the structure of the p. shigelloides o54 core was observed.200818954864
evaluation by real-time pcr of the expression of s. flexneri virulence-associated genes ospb and phon2 under different genetical backgrounds.under conditions of activated type iii secretion shigella flexneri up-regulates the expression of numerous genes, including the virulence plasmid (pinv)-encoded ospb and phon2 genes. ospb and phon2 are virulence-associated genes which are part of a bicistronic transcriptional unit encoding ospb, a protein (effector) of unknown function secreted by the type iii secretion (tts) apparatus, and phon2 (apyrase or atp-diphosphohydrolase), a periplasmic protein involved in polar icsa localization on th ...200818831939
in this issue: proteomics 20/2008.in this issue of proteomics you will find the following highlighted articles:comprehensively confirmed annotation of short orfsduring the california gold rush, prospectors did not look only for large nuggets to pave their road to riches - they also collected gold dust. the proteomic equivalent of dust is the small orf. it does not pay to put a lower limit on dust or orf size because almost any size may be turned into "cash" or an important peptide. wei et al. demonstrate how a combination of con ...200818924177
closing the diarrhoea diagnostic gap in indian children by the application of molecular techniques.a large proportion of diarrhoeal illnesses in children in developing countries are ascribed to an unknown aetiology because the only available methods, such as microscopy and culture, have low sensitivity. this study was aimed at decreasing the diagnostic gap in diarrhoeal disease by the application of molecular techniques. faecal samples from 158 children with and 99 children without diarrhoea in a hospital in south india were tested for enteric pathogens using conventional diagnostic methods ( ...200818927413
porin-incorporated liposome induces toll-like receptors 2- and 6-dependent maturation and type 1 response of dendritic cell.porin of shigella dysenteriae was incorporated in liposome (pil) and presented to mouse splenic dendritic cells (dc). pil up-regulated toll-like receptor (tlr) 2 and tlr6 on dc, showing that co-expression of the two tlrs is involved in recognition of porin. detection of myeloid differentiating factor 88 (myd88)-tlr2 complex confirmed interaction between the two for triggering the downstream signaling, which ultimately led to tlr2-dependent nuclear translocation of nuclear factor-kappa b. pil-ind ...200818931363
[new selective indicator medium for detection of aeromonas and plesiomonas: unisc agar].we evaluated a new selective indicator medium (unisc agar) for isolation of classical enteropathogens, aeromonas spp and plesiomonas shigelloides. the xylose fermentation capacity is indicated by a yellow color (fermenting agents) or blue (no fermenting agent). this, together with the oxidase test, establishes it as an indicator for detecting aeromonas and plesiomonas shigelloides. its productivity and selectivity, as assessed using the absolute count index and relative count index, indicate it ...200818853024
[the distribution and antimicrobial resistance tendency of pathogens associated with diarrhea in beijing].to monitor the constituents and resistant tendency of bacterial pathogens isolated from diarrheal patients in our hospital form 1994 to 2005 to offer the basis for guiding epidemiologic study, vaccination research and clinical treatment.200818843955
[analysis of pulsed-field gel electrophoresis molecular subtyping of shigella strains in shenzhen].to analyze the genetic relations of shigella isolated from shenzhen in 2001-2006 and develop primary molecular subtyping surveillance network of shigella.200818844079
[analysis on incidence of bacillary dysentery in jinan municipality from 1951 to 2005].to explore the epidemic characteristics of bacterial dysentery in jinan municipality, and to provide scientific basis for effective strategy for bacterial dysentery control.200818844085
prevention of the cytopathic effect induced by clostridium difficile toxin b by active rac1.clostridium difficile toxin b (tcdb) glucosylates low molecular weight gtp-binding proteins of the rho subfamily and thereby causes actin re-organization (cell rounding). this "cytopathic effect" has been generally attributed to rhoa inactivation. here we show that cells expressing non-glucosylatable rac1-q61l are protected from the cytopathic effect of tcdb. in contrast, cells expressing rhoa-q63l or mock-transfected cells are fully susceptible for the cytopathic effect of tcdb. these findings ...200818848548
[htpg protein of shigella flexneri 2a strain 2457t evokes inflammatory response in mice].to analyze the function of htpg of s. flexneri 2a 2457t, we constructed an htpg deletion mutant and a recovery mutant.200818837368
[detection of staphylococcus aureus, shigella spp., salmonella spp. in food by multiplex pcr].to establish a multiplex pcr method for simultaneous detection of staphylococcus aureus, shigella spp., salmonella spp. in food.200818839528
'form variation' of the o12 antigen is critical for persistence of salmonella typhimurium in the murine intestine.salmonella enterica subspecies i serotypes are responsible for the vast majority of salmonellosis in mammals and birds, yet only a few factors specific to this group that allow them to persist in this niche have been identified. we show that stm0557, a s. enterica subspecies i-specific gene encoding an inner membrane protein, is critical for faecal shedding and intestinal persistence of s. enterica serotype typhimurium atcc14028 in salmonella-resistant mice, but mutations in this gene do not dim ...200818826410
bacteriophage 2851 is a prototype phage for dissemination of the shiga toxin variant gene 2c in escherichia coli o157:h7.the production of shiga toxin (stx) (verocytotoxin) is a major virulence factor of escherichia coli o157:h7 strains (shiga toxin-producing e. coli [stec] o157). two types of shiga toxins, designated stx1 and stx2, are produced in stec o157. variants of the stx2 type (stx2, stx2c) are associated with high virulences of these strains for humans. a bacteriophage designated 2851 from a human stec o157 encoding the stx2c variant was described previously. nucleotide sequence analysis of the phage 2851 ...200818824528
evaluation of methods for isolation of dna for polymerase chain reaction (pcr)-based identification of pathogenic bacteria from pure cultures and water samples.polymerase chain reaction (pcr) provides a reliable detection of pathogenic bacteria in water samples. however, this method can be adversely influenced by the purity of the dna template. this is a particularly important obstacle when the bacterial dna is directly extracted from water samples. in this study we compared the suitability of 8 different methods for isolation of bacterial dna from pure cultures and 10 different methods for isolation of dna from water samples. the quality of extracted ...200818824796
gateways to clinical trials.11d10, 9vpnc-mncc; adalimumab, adefovir dipivoxil, alefacept, aln-rsv01, ame-133, amg-317, aminolevulinic acid methyl ester, amlodipine besylate/atorvastatin calcium, anisodamine, anti-il-5 receptor antibody, apremilast, aripiprazole, atacicept, atazanavir sulfate, atrasentan; banoxantrone, bevacizumab, bibw-2992, binodenoson, bms-387032; cac10, caldaret hydrate, cd-np, ceftobiprole medocaril, celivarone fumarate, certolizumab pegol, cholesteryl hydrophobized polysaccharide-her2 protein complex, ...200818773127
novel cassette arrays of integrons in clinical strains of enterobacteriaceae in china.one hundred and forty-two enterobacteriaceae isolates randomly selected from four general hospitals in nanjing region of china were investigated for antibiotic susceptibility, the presence of integrons and the characterisation of gene cassettes. eighty-five (59.9%) enterobacteriaceae strains contained class 1 integrons, and 17 (65.4%) of 26 shigella contained class 2 integrons. class 3 integrons were not detected in this study. restriction fragment length polymorphism (rflp) and dna sequencing a ...200818778917
novel fold of vira, a type iii secretion system effector protein from shigella flexneri.vira, a secreted effector protein from shigella sp., has been shown to be necessary for its virulence. it was also reported that vira might be related to papain-like cysteine proteases and cleave alpha-tubulin, thus facilitating intracellular spreading. we have now determined the crystal structure of vira at 3.0 a resolution. the shape of the molecule resembles the letter "v," with the residues in the n-terminal third of the 45-kda molecule (some of which are disordered) forming one clearly iden ...200818787201
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