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immunology of gut mucosal vaccines.understanding the mechanisms underlying the induction of immunity in the gastrointestinal mucosa following oral immunization and the cross-talk between mucosal and systemic immunity should expedite the development of vaccines to diminish the global burden caused by enteric pathogens. identifying an immunological correlate of protection in the course of field trials of efficacy, animal models (when available), or human challenge studies is also invaluable. in industrialized country populations, l ...201121198669
conformational changes in ipad from shigella flexneri upon binding bile salts provide insight into the second step of type iii secretion.shigella flexneri uses its type iii secretion apparatus (ttsa) to inject host-altering proteins into targeted eukaryotic cells. the ttsa is composed of a basal body and an exposed needle with invasion plasmid antigen d (ipad) forming a tip complex that controls secretion. the bile salt deoxycholate (doc) stimulates recruitment of the translocator protein ipab into the maturing ttsa needle tip complex. this process appears to be triggered by a direct interaction between doc and ipad. fluorescence ...201021126091
facile synthesis and antibacterial activity of naturally occurring 5-methoxyfuroflavone.a convenient synthesis of 5-methoxyfuroflavone (6, pongaglabol methyl ether), a constituent of some pongamia or millettia genus, was achieved by starting from 2,4-dihydroxy-6-methoxyacetophenone via a chalcone precursor, followed by treatment with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (ddq). this five-step reaction (total yield: 21.6%) is more facile with that of previously utilized procedures using each different starting material. antibacterial activities of the above compound and its prec ...201021139271
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
antimicrobial resistance patterns and prevalence of class 1 and 2 integrons in shigella flexneri and shigella sonnei isolated in uzbekistan.abstract:201021143880
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
lactobacillus plantarum lipoteichoic acid down-regulated shigella flexneri peptidoglycan-induced inflammation.bacterial peptidoglycans (pgns) are recognized by the host's innate immune system. this process is mediated by the nod/card family of proteins, which induces inflammation by activating nuclear factor (nf)-κb. excessive activation of monocytes by shigella flexneri pgn (flexpgn) leads to serious inflammatory diseases such as intestinal bowel diseases (ibd) and crohn's disease. in this study, we examined whether lactobacillus plantarum lipoteichoic acid (plta) could attenuate the pro-inflammatory s ...201021129777
[microsporidium spp. infection in an immunocompromised child diagnosed by polymerase chain reaction].microsporidium spp. may lead to a variety of clinical pictures like sinusitis, keratoconjunctivitis, hepatitis, myositis, peritonitis, nephritis, encephalitis and pneumonia in case of immune deficiencies. in this report, a case of diarrhea due to microsporidium spp. has been presented. a four years old male patient who was followed with the diagnosis of myotonic dystrophia, was admitted to the hospital with the complaints of respiratory distress and fever. due to the history of recurrent infecti ...201021063982
arginine-dependent acid-resistance pathway in shigella boydii.ability to survive the low ph of the human stomach is considered be an important virulent determinant. it was suggested that the unique acid tolerance of shigella boydii 18 cdph, the strain implicated in a 1998 outbreak, may have played an important role in surviving the acidic food (bean salad). the strain was capable of inducing arginine-dependent acid-resistance (adar) pathway. this pathway was assumed to be absent in shigella sp. here, we have examined occurrence and efficacy of adar pathway ...201021136041
the shigella t3ss needle transmits a signal for mxic release, which controls secretion of effectors.type iii secretion systems (t3sss) are key determinants of virulence in many gram-negative bacteria, including animal and plant pathogens. they inject 'effector' proteins through a 'needle' protruding from the bacterial surface directly into eukaryotic cells after assembly of a 'translocator' pore in the host plasma membrane. secretion is a tightly regulated process, which is blocked until physical contact with a host cell takes place. host cell sensing occurs through a distal needle 'tip comple ...201021143311
entrapment of intracytosolic bacteria by septin cage-like structures.actin-based motility is used by various pathogens for dissemination within and between cells. yet host factors restricting this process have not been identified. septins are gtp-binding proteins that assemble as filaments and are essential for cell division. however, their role during interphase has remained elusive. here, we report that septin assemblies are recruited to different bacteria that polymerize actin. we observed that intracytosolic shigella either become compartmentalized in septin ...201021075354
extended-spectrum ß-lactamase production in shigella flexneri.emergence of multidrug-resistant strains of shigella is a growing concern across the globe. third-generation cephalosporins are used for treating infections caused by multidrug-resistant shigellae. however, resistance to these cephalosporin antibiotics due to extended-spectrum ß-lactamases, has emerged as a new problem. so far extended-spectrum ß-lactamases producing shigella has not been reported from pakistan. we report such a case in shigella flexneri from an 8-year old girl with acute dysent ...201021078255
shigellosis from an interactive fountain: implications for regulation.in july 2003, the authors investigated an outbreak of shigella sonnei infections in marion county, oregon. nineteen confirmed and 37 presumptive cases, mostly young children, were identified. a case-control study implicated play in an interactive fountain in a city park (matched odds ratio undefined; p < .002). the association was confirmed by a cohort study among local schoolchildren (rr [relative risk] = 12.6, p < .001) that allowed the authors to estimate that > 500 persons became ill. founta ...201021133311
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
enteric glia protect against shigella flexneri invasion in intestinal epithelial cells: a role for s-nitrosoglutathione.enteric glial cells (egcs) are important regulators of intestinal epithelial barrier (ieb) functions. egc-derived s-nitrosoglutathione (gsno) has been shown to regulate ieb permeability. whether egcs and gsno protect the ieb during infectious insult by pathogens such as shigella flexneri is not known.201021139062
[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
microbiological quality of blue mussels (mytilus edulis) in nunavik, quebec: a pilot study.this pilot study was aimed at documenting the presence of fecal indicators and enteric pathogens in blue mussels (mytilus edulis) from 6 communities in nunavik, quebec. one to four 2 kg samples of mussels were collected at low tide in each community. samples were investigated by enumeration methods for the fecal indicators enterococci, escherichia coli, f-specific coliphages, clostridium perfringens, and by molecular identification for the pathogens norovirus, salmonella spp., campylobacter jeju ...201021076488
[secondary structure of ssoii-like (cytosine-5)-dna methyltransferases n-terminal region determined by circular dichroism spectroscopy].(cytosine-5)-dna methyltransferase ssoii (m.ssoii) has a long n-terminal region (1-71 residues) preceding the sequence with conservative motifs, which are characteristic for all dna methyltransferases of such kind. the presence of this region provides m.ssoii capability to act as a transcription regulator in ssoii restriction-modification system. to perform its regulatory function, m.ssoii binds specifically to a 15-mer inverted repeat in the promoter region of ssoii restriction-modification sys ...201021090246
enteropathogenic e. coli non-lee encoded effectors nleh1 and nleh2 attenuate nf-κb activation.enteric bacterial pathogens have evolved sophisticated strategies to evade host immune defences. some pathogens deliver anti-inflammatory effector molecules into the host cell cytoplasm via a type iii secretion system (t3ss). enteropathogenic escherichia coli (epec) inhibits inflammation by an undefined, t3ss-dependent mechanism. two proteins encoded outside of the epec locus of enterocyte effacement (lee) pathogenicity island, non-lee-encoded effector h1 (nleh1) and h2 (nleh2), display sequence ...201021091507
isolation and characterization of shigella flexneri g3, capable of effective cellulosic saccharification under mesophilic conditions.a novel shigella strain (shigella flexneri g3) showing high cellulolytic activity under mesophilic, anaerobic conditions was isolated and characterized. the bacterium is gram negative, short rod shaped, and nonmotile and displays effective production of glucose, cellobiose, and other oligosaccharides from cellulose (avicel ph-101) under optimal conditions (40°c and ph 6.5). approximately 75% of the cellulose was hydrolyzed in modified atcc 1191 medium containing 0.3% cellulose, and the oligosacc ...201021097577
thrombotic microangiopathies: thrombotic thrombocytopenic purpura / hemolytic uremic syndrome.thrombotic microangiopathies (tmas) are pathological conditions characterized by generalized microvascular occlusion by platelet thrombi, thrombocytopenia, and microangiopathic hemolytic anemia. two typical phenotypes of tmas are hemolytic- uremic syndrome (hus) and thrombotic thrombocytopenic purpura (ttp). other disorders occasionally present with similar manifestations. depending on whether renal or brain lesions prevail, two pathologically indistinguishable but somehow clinically different d ...201021103695
environmental contamination of hokersar wetland waters in kashmir himalayan valley, india.this paper investigates the environmental contamination of himalayan wetland ecosystem (hokersar, kashmir) by analyzing the distribution and loading of bacterial population in waters. seven locations representing heterogeneous spatial habitat zonation of the wetland were studied. site-specific variability in bacterial load was markedly discernible at doodhganga inlet and zainakoot locations, with maximum values in the range of 242-276/100 ml against soziath, an outlet, with minimum value of 157- ...201021114125
[viable non-culturable bacteria].viable but non-culturable cells (vbnc) are defined as live bacteria, but which do not either grow or divide. such bacteria cannot be cultivated on conventional media (they do not form colonies on solid media, they do not change broth appearance), but their existence can be proved using other methods. the switch to the vbnc stage has been described and documented for several bacterial species: vibrio spp. (cholerae, vulnificus and other species), escherichia coli (including ehec), campylobacter j ...201021038700
prevalence and characterization of human shigella infections in henan province, china, in 2006.in 2006, 3,531 fecal samples were collected from patients with diarrhea in henan province, china. a total of 467 (13.2%) shigella strains were isolated and serotyped. seventy-one shigella flexneri strains were characterized by mic determination, pulsed-field gel electrophoresis (pfge), and detection of genes encoding cephalosporin resistance. most infections were caused by s. flexneri variant x [iv:(7),8] (27.6%), s. sonnei (24.2%), and s. flexneri 2a (20.8%). however, large regional differences ...201021068291
the host outer membrane proteins ompa and ompc are associated with the shigella phage sf6 virion.assembly of dsdna bacteriophage is a precisely programmed process. potential roles of host cell components in phage assembly haven't been well understood. it was previously reported that two unidentified proteins were present in bacteriophage sf6 virion (casjens et al, 2004, j.mol.biol. 339, 379-394, fig. 2a). using tandem mass spectrometry, we have identified the two proteins as outer membrane proteins (omps) ompa and ompc from its host shigella flexneri. the transmission electron cryo-microsco ...201021071053
the structure of the escherichia coli o148 lipopolysaccharide core region and its linkage to the o-specific polysaccharide.recently it was demonstrated that shigella dysenteriae type 1, a cause of severe dysentery epidemics, gained its o-specific polysaccharide (o-sp) from escherichia coli o148. the o-sps of these bacteria differ only by a galactose residue in the repeat unit of s. dysenteriae type 1 in place of a glucose residue in e. coli o148. herein, we analyzed the core structure and its linkage to the o-sp in e. coli o148 lps. both were found to be identical to those of s. dysenteriae type 1 structures, furthe ...201021074753
shigella flexneri spa15 crystal structure verified in solution by double electron electron resonance.shigella flexneri spa15 is a chaperone of the type 3 secretion system, which binds a number of effectors to ensure their stabilization prior to secretion. one of these effectors is ipgb1, a mimic of the human ras-like rho guanosine triphosphatase rhog. in this study, spa15 alone and in complex with ipgb1 has been studied by double electron electron resonance, an experiment that gives distance information showing the spacial separation of attached spin labels. this distance is explained by determ ...201021075116
biochemical characterization of udp-gal:glcnac-pyrophosphate-lipid β-1,4-galactosyltransferase wfed, a new enzyme from shigella boydii type 14 that catalyzes the second step in o-antigen repeating-unit synthesis.the o antigen is the outer part of the lipopolysaccharide (lps) in the outer membrane of gram-negative bacteria and contains many repeats of an oligosaccharide unit. it contributes to antigenic variability and is essential to the full function and virulence of bacteria. shigella is a gram-negative human pathogen that causes diarrhea in humans. the o antigen of shigella boydii type 14 consists of repeating oligosaccharide units with the structure [→6-d-galpα1→4-d-glcpaβ1→6-d-galpβ1→4-d-galpβ1→4-d ...201021057010
cell-cell propagation of nf-κb transcription factor and map kinase activation amplifies innate immunity against bacterial infection.the enteroinvasive bacterium shigella flexneri uses multiple secreted effector proteins to downregulate interleukin-8 (il-8) expression in infected epithelial cells. yet, massive il-8 secretion is observed in shigellosis. here we report a host mechanism of cell-cell communication that circumvents the effector proteins and strongly amplifies il-8 expression during bacterial infection. by monitoring proinflammatory signals at the single-cell level, we found that the activation of the transcription ...201021093316
development of a quantitative rt-pcr assay to examine the kinetics of ribosome depurination by ribosome inactivating proteins using saccharomyces cerevisiae as a model.ricin produced by the castor bean plant and shiga toxins produced by pathogenic escherichia coli (stec) and shigella dysenteriae are type ii ribosome inactivating proteins (rips), containing an enzymatically active a subunit that inhibits protein synthesis by removing an adenine from the α-sarcin/ricin loop (srl) of the 28s rrna. there are currently no known antidotes to shiga toxin or ricin, and the ability to screen large chemical libraries for inhibitors has been hindered by lack of quantitat ...201021098653
anaerobic environment of the intestine primes pathogenic shigella for infection.marteyn et al. have investigated the role of oxygen and the regulator fnr in infection by the intracellular enteric pathogen shigella flexneri. fnr is active under anaerobic conditions like those present in the lumen of the distal intestine. fnr causes elongation of a secretion apparatus required for bacterial entry into cells and represses secretion of proteins that trigger entry. higher oxygen levels present at the intestinal cell surface are sufficient to inactivate fnr, thereby derepressing ...201021073287
caging targets for destruction.intracellular bacterial pathogens engage in a tug-of-war with innate host defenses. in this issue of cell host & microbe, mostowy et al. (2010) identify a role for the septin family of cytoskeletal proteins in targeting intracellular shigella to the autophagy pathway.201021075349
assessment of the underestimation of childhood diarrhoeal disease burden in israel.summarywe determined the extent by which mandatory reporting on isolates of shigella and salmonella underestimates the burden of diarrhoeal diseases in individuals aged <17 years in israel and examined paediatricians' knowledge, attitudes and practices related to patient visits with diarrhoeal diseases. sources of data were a nationwide population-based telephone survey for presence of diarrhoeal diseases, maccabi healthcare services databases and a mail survey among its paediatricians. monte ca ...201021087537
[rapid detection of shigella dysenteriae by pcr assay].based on the invasive plasmid antigen h gene (ipah) of s. dysenteriae, one pair of specific primers was designed for pcr assays in this study. the concentrations of dntp, mg2+ and primer, dosage of taq dna polymerase, annealing temperature and circulating parameter in the pcr amplification system were optimized. in this way, a rapid and stable method of pcr assay for the detection of s. dysenteriae was established. the specificity and sensitivity of pcr were also analyzed. the detection limits o ...201021033439
counting bacteria on a microfluidic chip.this paper reports a lab-on-a-chip device that counts the number of bacteria flowing through a microchannel. the bacteria number counting is realized by a microfluidic differential resistive pulse sensor (rps). by using a single microfluidic channel with two detecting arm channels placed at the two ends of the sensing section, the microfluidic differential rps can achieve a high signal-to-noise ratio. this method is applied to detect and count bacteria in aqueous solution. the detected rps signa ...201021035606
case-control study of diarrheal disease etiology in a remote rural area in western thailand.the objective was to assess the association of enteric pathogens in diarrheal disease in a remote rural area in thailand. stool specimens were collected from 236 children aged 3 months to 5 years with acute diarrhea (cases) and from 236 asymptomatic controls. standard microbiologic methods, and enzyme immunoassay for viral pathogens, giardia, and cryptosporidium, were used to identify enteric pathogens with susceptibility testing by disk diffusion. campylobacter, plesiomonas, salmonella, and ent ...201021036846
laboratory based surveillance of travel-related shigella sonnei and shigella flexneri in alberta from 2002 to 2007.abstract: between 2002 and 2007, travel related cases of shigella sonnei and s. flexneri in alberta, canada were acquired from central america, the indian subcontinent and north america. of this group, resistance to ciprofloxacin and nalidixic acid was identified in isolates from patients who had travelled to the indian subcontinent. this study provides a canadian perspective to a growing body of literature linking ciprofloxacin and nalidixic acid resistance to travel to the indian subcontinent. ...201021040566
safety, dose, immunogenicity, and transmissibility of an oral live attenuated shigella flexneri 2a vaccine candidate (sc602) among healthy adults and school children in matlab, bangladesh.in double-blind trials in bangladesh, 88 adults, and 79 children (8-10 years) were randomized to receive either a single oral dose of 1 × 10(4), 1 × 10(5) or 1 × 10(6)cfu of sc602 (a live, attenuated shigella flexneri 2a strain vaccine) or placebo. in the adult outpatient 1 × 10(6) cfu group, severe joint pain and body aches were reported by one and two vaccinees respectively. in the adult inpatient trial, sc602 was isolated from 3 volunteers, pre-vaccination antibody titers were high, and fourf ...201021040694
biosensors for efficient diagnosis of leishmaniasis: innovations in bioanalytics for a neglected disease.the need for reliable, fast diagnostics is closely linked to the need for safe, effective treatment of the so-called "neglected" diseases. the list of diseases with no field-adapted diagnostic tools includes leishmaniasis, shigella, typhoid, and bacterial meningitis. leishmaniasis, in particular, is a parasitic disease caused by leishmania spp. transmitted by infected phlebotomine sandfly, which remains a public health concern in developing countries with ca. 12 million people infected and 350 m ...201021043437
research progress in shigella in the postgenomic era.gram-negative, facultative intracellular anaerobes of the genus shigella, the principal etiologic agents of shigellosis, continue to pose a threat to public health. shigellosis causes 1.1 million deaths with over 164 million annual cases. the shigella spp. can be divided into four serogroups: shigella dysenteriae, shigella flexneri, shigella boydii and shigella sonnei. the completion of seven shigella genome sequences of representative strains from each of the shigella species has introduced an ...201021046319
detection of representative enteropathogenic bacteria, vibrio spp., pathogenic escherichia coli, salmonella spp., shigella spp., and yersinia enterocolitica, using a virulence factor gene-based oligonucleotide microarray.rapid identification of enteropathogenic bacteria in stool samples is critical for clinical diagnosis and antimicrobial therapy. in this study, we describe the development of an approach that couples multiplex pcr with hybridization to a dna microarray, to allow the simultaneous detection of the 10 pathogens. the microarray was synthesized with 20-mer oligonucleotide probes that were designed to be specific for virulence-factor genes of each strain. the detection limit for genomic dna from a sin ...201021046348
predation of human pathogens by the predatory bacteria micavibrio aeruginosavorus and bdellovibrio bacteriovorus.the focus of this study was to evaluate the potential use of the predatory bacteria bdellovibrio bacteriovorus and micavibrio aeruginosavorus to control the pathogens associated with human infection.201021114596
laboratory detection of extended-spectrum-beta-lactamase-producing enterobacteriaceae: evaluation of two screening agar plates and two confirmation techniques.the worldwide prevalence of extended-spectrum-beta-lactamase-producing esbl-producing enterobacteriaceae (esbl-e) is increasing, making the need for optimized detection techniques more urgent. in this study we investigated the performance of two esbl-e screening and two esbl-e confirmation techniques. in accordance with the dutch national guidelines (www.wip.nl), a collection of 642 highly resistant enterobacteriaceae strains, as identified by vitek2, was used to test the performances of two scr ...201021123527
controlled study on enteropathogens in travellers returning from the tropics with and without diarrhoea.clin microbiol infect abstract: diarrhoea is the most frequent health problem among travellers in the tropics. however, data on the spectrum and relevance of enteropathogens in international travellers with and without diarrhoea are limited. stool samples from 114 cases of diarrhoea in travellers returning from the tropics were collected for microbiological examination and pcr for norovirus genogroups i and ii, enteroaggregative escherichia coli (eaec), and enterotoxigenic e. coli (etec) produci ...201021054662
evidence of cellular immune response to outer membrane protein of salmonella typhimurium in patients with enthesitis-related arthritis subtype of juvenile idiopathic arthritis.enthesitis-related arthritis subtype of juvenile idiopathic arthritis (jia-era) clinically resembles reactive arthritis (rea). in patients with rea the immune response is targeted at the outer membrane protein (omp) of salmonella typhimurium. we studied the immune response in jia-era to s. typhimurium omp.201021041273
the effects of x-ray radiation on escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri inoculated on whole roma tomatoes.in the last two decades several foodborne disease outbreaks associated with produce were reported. tomatoes, in particular, have been associated with several multi-state salmonella outbreaks. inactivation of inoculated escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri on whole roma tomato surfaces by x-ray at 0.1, 0.5, 0.75, 1.0, and 1.5 kgy was studied. the main purpose of this study was to achieve a 5 log reduction in consistent with the recommendation ...201020832685
prevalence of shigellosis diarrhoea in a paediatrics population: hospital based survey in bangui, central african republic.shigellosis is still a major public health problem in sub-saharan countries, especially among children.201021045359
[susceptibility surveillance of clinical isolates to fluoroquinolone antimicrobial agents from 2003 to 2008: post-marketing study of prulifloxacin].yearly changes in the susceptibility of clinical isolates to ulifloxacin (ufx) and other fluoroquinolones were examined through surveys over 3 periods. in the first survey, 534 strains derived from 19 species were collected from clinical specimens during 6 months from december 2003 to may 2004. in the same way, 805 strains were collected from december 2005 to may 2006 in the second survey, and 863 strains were from december 2007 to may 2008 in the third survey. over these 3 study periods, the su ...201020976880
evaluation of bacterial multiplication in cleaning cloths containing different quantities of organic matter.to determine a proper length of time for cleaning cloth usage, the present work aimed to evaluate bacterial multiplication in artificially contaminated cleaning cloths containing different amounts of organic matter.201021045369
[detection and drug resistance analysis of extended-spectrum beta-lactamases-producing shigella in pediatric patients].to investigate the occurrence and drug resistance of extended-spectrum beta-lactamases (esbls)-producing strains of shigella in pediatric patients, so as to provide information for clinical treatment.201021055309
plasmid-encoded multidrug resistance: a case study of salmonella and shigella from enteric diarrhea sources among humans.salmonellosis and shigellosis are significant and persistent causes of diarrheal diseases among humans in developing countries. with that in mind, the current study investigates the occurrence of plasmid-encoded multidrug resistances in salmonella and shigella from diarrheal cases among humans. the isolates were characterized by serotyping, antimicrobial-susceptibility testing, transfer experiments and curing. the extended spectrum β-lactamase (esbl) was detected by the double disc diffusion syn ...201021031258
decrease in shigellosis-related deaths without shigella spp.-specific interventions, asia.in 1999, a review of the literature for 1966-1997 suggested that ≈1.1 million persons die annually of shigellosis, including ≈880,000 in asia. our recent review of the literature for 1990-2009 indicates that ≈125 million shigellosis cases occur annually in asia, of which ≈14,000 are fatal. this estimate for illnesses is similar to the earlier estimate, but the number of deaths is 98% lower; that is, the lower estimate of deaths is associated with markedly reduced case-fatality rates rather than ...201021029529
[antibacterial antibodies in human immunoglobulins and sera: past and present].to measure levels of several types of antibacterial antibodies in preparations of normal human immunoglobulin as well as in samples of donor sera obtained in 1965 and 2009.201021061576
genetic characterization of atypical shigella flexneri isolated in korea.three types of serotypically atypical shigella flexneri strains were isolated from 2007 to 2008 in patients at the korea national institute of health (nih). these strains were characterized and compared with serologically typical s.flexneri. one type of strain either displayed nonreacting typing or grouping sera, reacting strongly only with polyb antisera, which indicates this strain is s. flexneri (polyb:un). the second type displayed reactions with one of the typing sera (iv) and did not bind ...201021030833
effects of backbone substitutions on the conformational behavior of shigella flexneri o-antigens: implications for vaccine strategy.the o-antigen (o-ag), the polysaccharide part of the lipopolysaccharide, is the major target of the serotype-specific protective humoral response elicited upon host infection by shigella flexneri, the main causal agent of the endemic form of bacillary dysentery. the o-ag repeat units (rus) of 12 s. flexneri serotypes share the tetrasaccharide backbone →2)-α-l-rhap-(1 → 2)-α-l-rhap-(1 → 3)-α-l-rhap-(1 → 3)-β-d-glcpnac-(1→, with site-selective glucosylation(s) and/or o-acetylation defining the ser ...201021030536
comparison of chromogenic biolog rainbow agar shigella/aeromonas with xylose lysine desoxycholate agar for isolation and detection of shigella spp. from foods.shigella outbreaks are widely reported throughout the world. however, it remains a challenge to isolate shigella spp. from foods by using conventional microbiological media. the main objective of this study was to determine the effectiveness of a novel chromogenic medium, rainbow agar shigella/aeromonas (rainbow agar), for the isolation and detection of shigella spp. in foods. all four shigella species, s. sonnei, s. flexneri, s. dysenteriae, and s. boydii, were studied. rainbow agar was compare ...201020819355
enhancement of reactive oxygen species production and chlamydial infection by the mitochondrial nod-like family member nlrx1.chlamydia trachomatis infections cause severe and irreversible damage that can lead to infertility and blindness in both males and females. following infection of epithelial cells, chlamydia induces production of reactive oxygen species (ros). unconventionally, chlamydiae use ros to their advantage by activating caspase-1, which contributes to chlamydial growth. nlrx1, a member of the nod-like receptor family that translocates to the mitochondria, can augment ros production from the mitochondria ...201020959452
shigella deploy multiple countermeasures against host innate immune responses.although the intestinal epithelium is equipped with multiple defense systems that sense bacterial components, transmit alarms to the immune system, clear the bacteria, and renew the injured epithelial lining, mucosal bacterial pathogens are capable of efficiently colonizing the intestinal epithelium, because they have evolved systems that modulate the inflammatory and immune responses of the host and exploit the harmful environments as replicative niches. in this review we highlight current topi ...201020934372
domains of the shigella flexneri type iii secretion system ipab protein involved in secretion regulation.type iii secretion systems (t3sss) are key determinants of virulence in many gram-negative bacterial pathogens. upon cell contact, they inject effector proteins directly into eukaryotic cells through a needle protruding from the bacterial surface. host cell sensing occurs through a distal needle "tip complex," but how this occurs is not understood. the tip complex of quiescent needles is composed of ipad, which is topped by ipab. physical contact with host cells initiates secretion and leads to ...201020937761
combination of two separate binding domains defines stoichiometry between type iii secretion system chaperone ipgc and translocator protein ipab.type iii secretion systems (ttsss) utilized by enteropathogenic bacteria require the presence of small, acidic virulence-associated chaperones for effective host cell infection. we adopted a combination of biochemical and cellular techniques to define the chaperone binding domains (cbds) in the translocators ipab and ipac associated with the chaperone ipgc from shigella flexneri. we identified a novel cbd in ipab and furthermore precisely mapped the boundaries of the cbds in both translocator pr ...201020937829
characterization and antimicrobial activity of 4-(β-d-glucopyranosyl-1→4-α-l-rhamnopyranosyloxy)-benzyl thiocarboxamide; a novel bioactive compound from moringa oleifera seed extract.antimicrobial activity of crude seed extract of moringa oleifera was investigated by thin layer chromatography bioassay against escherichia coli, pseudomonas aeruginosa, staphylococcus aureus, cladosporium cladosporioides, and penicillium sclerotigenum; most of them were prominently inhibited by an isolate with r(f) 0.92-0.96. characterization and identification of the extract revealed the occurrence of three bioactive compounds: 4-(α-l-rhamnopyranosyloxy)benzyl isothiocyanate, methyl n-4-(α-l-r ...201020941575
expression of bacterial virulence factors and cytokines during in vitro macrophage infection by enteroinvasive escherichia coli and shigella flexneri: a comparative study.enteroinvasive escherichia coli (eiec) and shigella spp cause bacillary dysentery in humans by invading and multiplying within epithelial cells of the colonic mucosa. although eiec and shigella share many genetic and biochemical similarities, the illness caused by shigella is more severe. thus, genomic and structure-function molecular studies on the biological interactions of these invasive enterobacteria with eukaryotic cells have focused on shigella rather than eiec. here we comparatively stud ...201020944993
an fda bioinformatics tool for microbial genomics research on molecular characterization of bacterial foodborne pathogens using microarrays.advances in microbial genomics and bioinformatics are offering greater insights into the emergence and spread of foodborne pathogens in outbreak scenarios. the food and drug administration (fda) has developed a genomics tool, arraytrack™, which provides extensive functionalities to manage, analyze, and interpret genomic data for mammalian species. arraytrack™ has been widely adopted by the research community and used for pharmacogenomics data review in the fda's voluntary genomics data submissio ...201020946615
integron types, gene cassettes, antimicrobial resistance genes and plasmids of shigella sonnei isolates from outbreaks and sporadic cases in taiwan.this study analysed the presence, location and transferability of integrons and antibiotic resistance genes in 103 shigella sonnei outbreak isolates and in 32 sporadic isolates from taiwan. multiple antimicrobial resistance was common in both outbreak (95 %) and sporadic (97 %) isolates. class 1 integrons were present in 34 outbreak isolates (33 %) and in six sporadic isolates (19 %). this study is the first, to our knowledge, to identify an atypical sul3-associated class 1 integron carrying the ...201020947666
rapid multiple-locus variable-number tandem-repeats analysis of shigella spp. using multicolour capillary electrophoresis.the multiple-locus variable-number tandem-repeats analysis (mlva) method for genotyping has proven to be a fast and reliable typing tool in several bacterial species. mlva is in our laboratory the routine typing method for salmonella enterica subsp. enterica serovar typhimurium, escherichia coli (two assays), listeria monocytogenes and yersinia enterocolitica. the gram-negative invasive enteropathogenic bacterium shigella is the most common cause of bacillary dysentery (shigellosis) worldwide, a ...201020951171
surveillance of shigellosis by real-time pcr suggests underestimation of shigellosis prevalence by culture-based methods in a population of rural china.shigellosis is a leading public health issue in china, especially in children under 5 years of age. the disease burden of shigellosis is usually underestimated by conventional culture. in this study, real-time pcr was applied to detect shigella infection in parallel with routine culture, to investigate the true burden of disease caused by shigella spp.201020951728
improved fructosylated chondroitin production by kfoc overexpression in e. coli k4.escherichia coli k4 is one of the bacteria expressing a surface polysaccharide, indicated as capsular polysaccharide (k-antigen), showing a chemical structure that resembles that of metabolites commonly used in pharmaceutical applications. in this study we provide evidence that homologous overexpression of the chondroitin polymerase, encoded by the kfoc gene, acts on a potential bottleneck for production of capsular polysaccharide, and increases productivity by 100%. however, we also demonstrate ...201020888875
subtype prevalence, plasmid profiles and growing fluoroquinolone resistance in shigella from kolkata, india (2001-2007): a hospital-based study.shigellosis is a major public health problem, and increasing antimicrobial resistance has complicated its treatment. we report isolation frequency, plasmid profiles and antimicrobial resistance of shigella subtypes in kolkata, india, from a prospective hospital-based study.201020955371
prominent human health impacts from several marine microbes: history, ecology, and public health implications.this paper overviews several examples of important public health impacts by marine microbes and directs readers to the extensive literature germane to these maladies. these examples include three types of dinoflagellates (gambierdiscus spp., karenia brevis, and alexandrium fundyense), bmaa-producing cyanobacteria, and infectious microbes. the dinoflagellates are responsible for ciguatera fish poisoning, neurotoxic shellfish poisoning, and paralytic shellfish poisoning, respectively, that have pl ...201020976073
atypical class 1 integron coexists with class 1 and class 2 integrons in multi-drug resistant shigella flexneri isolates from china.the antimicrobial resistance and the character of integrons were determined in 58 shigella flexneri strains isolated from china. all isolates were multi-drug resistant and found to carry integrons of class 1 (94.8%), class 2 (100%), or both (94.8%). no inti3 was detected. the typical class 1 integrons were found in conjugative plasmids and could be transferred to the recipient e. coli dh5α. the gene cassettes of typical class 1 integrons dfra17-aada5 and dfra12-orff-aada2 were detected in 54 str ...201020976456
incidence and antimicrobial resistance of enteropathogens isolated from an integrated aquaculture system.to evaluate an integrated aquaculture system, microbiological analyses of water used in this system were carried out and the incidence and antimicrobial resistance of enteropathogens were determined in the related ecosystem.201021029138
shigella spp. antimicrobial drug resistance, papua new guinea, 2000-2009. 201021029550
near-atomic resolution analysis of bipd, a component of the type iii secretion system of burkholderia pseudomallei.burkholderia pseudomallei, the causative agent of melioidosis, possesses a type iii protein secretion apparatus that is similar to those found in salmonella and shigella. a major function of these secretion systems is to inject virulence-associated proteins into target cells of the host organism. the bipd gene of b. pseudomallei encodes a secreted virulence factor that is similar in sequence and is most likely to be functionally analogous to ipad from shigella and sipd from salmonella. proteins ...201020823511
normal aerobic bacterial conjunctival flora in the crab-eating raccoon (procyon cancrivorus) and coati (nasua nasua) housed in captivity in pernambuco and paraiba (northeast, brazil).to determine the normal aerobic bacterial conjunctival population of the coatis and the crab-eating raccoons housed in captivity in the pernambuco and paraiba states of brazil.201020840103
molecular mechanisms of necroptosis: an ordered cellular explosion.for a long time, apoptosis was considered the sole form of programmed cell death during development, homeostasis and disease, whereas necrosis was regarded as an unregulated and uncontrollable process. evidence now reveals that necrosis can also occur in a regulated manner. the initiation of programmed necrosis, 'necroptosis', by death receptors (such as tumour necrosis factor receptor 1) requires the kinase activity of receptor-interacting protein 1 (rip1; also known as ripk1) and rip3 (also kn ...201020823910
formulation and immunogenicity studies of type iii secretion system needle antigens as vaccine candidates.bacterial infections caused by shigella flexneri, salmonella typhimurium, and burkholderia pseudomallei are currently difficult to prevent due to the lack of a licensed vaccine. here we present formulation and immunogenicity studies for the three type iii secretion system (ttss) needle proteins mxih(δ5), prgi(δ5), and bsal(δ5) (each truncated by five residues at its c terminus) as potential candidates for vaccine development. these antigens are found to be thermally stabilized by the presence of ...201020845448
assessment of the microbiological safety of dried spices and herbs commercialized in spain.spices and herbs are natural products or their blends that must be free of extraneous matter content. conventional production of these products implicates a number of hygienic problems so spices and herbs may be exposed to a wide range of microbial contamination during pre- and post-harvest and they can present high microbial counts. in this study, we have analyzed the microbial quality of 53 samples of spices and dry herbs collected from spanish markets detecting a contamination of samples of s ...201020848208
dysbiosis of fecal microbiota in crohn's disease patients as revealed by a custom phylogenetic microarray.a custom phylogenetic microarray composed of small subunit ribosomal rna probes, representing ≈500 bacterial species from the human and animal gut, was developed and evaluated for analysis of gut microbial diversity using fecal samples from healthy subjects and crohn's disease (cd) patients.201020848492
ikkα contributes to canonical nf-κb activation downstream of nod1-mediated peptidoglycan recognition.during pathogen infection, innate immunity is initiated via the recognition of microbial products by pattern recognition receptors and the subsequent activation of transcription factors that upregulate proinflammatory genes. by controlling the expression of cytokines, chemokines, anti-bacterial peptides and adhesion molecules, the transcription factor nuclear factor-kappa b (nf-κb) has a central function in this process. in a typical model of nf-κb activation, the recognition of pathogen associa ...201020976174
predacious bacteria, bdellovibrio with potential for biocontrol.bacteria of the genus of bdellovibrio are highly motile gram-negative predators of other gram-negative bacteria causing lysis of their prey. here we report results of studies on the interactions of bdellovibrio with species of alcaligenes, campylobacter, erwinia, escherichia, helicobacter, pseudomonas, legionella, and shigella in agar lower, liquid media and cells attached to a surface. helicobacter pylori was studied employing both actively growing and viable but nonculturable (vbnc) cells. the ...201020850380
infectious colitis.purpose of review: the incidence of gastrointestinal infections continues to increase and infectious colitis contributes to significant morbidity and mortality worldwide. the purpose of this review is to highlight the recent advances in knowledge of pathogens causing infectious colitis. we describe the various pathogens and specifically focus on enterohemorrhagic escherichia coli (ehec) o157:h7, salmonella, shigella, campylobacter, and entamoeba histolytica infections, and their impact on long-t ...201020856114
improved detection of five major gastrointestinal pathogens by use of a molecular screening approach.the detection of bacterial and parasitic gastrointestinal pathogens through culture and microscopy is laborious and time-consuming. we evaluated a molecular screening approach (msa) for the detection of five major enteric pathogens: salmonella enterica, campylobacter jejuni, giardia lamblia, shiga toxin-producing escherichia coli (stec), and shigella spp./enteroinvasive e. coli (eiec), for use in the daily practice of a clinical microbiology laboratory. the msa consists of prescreening of stool ...201020861334
antidiarrheal activity of extracts and compound from trilepisium madagascariense stem bark.the present study was performed to evaluate the preventive and curative antidiarrheal effects of the methanol extract, fractions and compound from the stem bark of trilepisium madagascariense in rats.201020871767
defensins play a crucial role in protecting mice against oral shigella flexneri infection.an earlier study revealed that 4-day-old mice, but not older mice, were infected with invasive shigella strains. here we attempted to determine the underlying mechanism that induces inflammation in the intestines of neonate mice after oral shigella infection. wild-type balb/c mice of different ages (7, 14, and 35 days old) were orally administered gfp-expressing shigella flexneri 5a m90t strain (5 x 10⁹ cfu) and analyzed for colonization 6h following infection. we found that shigella localized i ...201020888321
pediatric diarrhea in southern ghana: etiology and association with intestinal inflammation and malnutrition.diarrhea is a major public health problem that affects the development of children. anthropometric data were collected from 274 children with (n = 170) and without (n = 104) diarrhea. stool specimens were analyzed by conventional culture, polymerase chain reaction for enteroaggregative escherichia coli (eaec), shigella, cryptosporidium, entamoeba, and giardia species, and by enzyme-linked immunosorbent assay for fecal lactoferrin levels. about 50% of the study population was mildly to severely m ...201020889896
selective testing of ß-galactosidase activity in the laboratory identification of salmonella and shigella species.salmonella and shigella species are pathogens of great medical and public health importance. however, laboratory identification of these organisms is time consuming. using current standard laboratory algorithms, the vast majority of organisms submitted for serological typing with salmonella-specific and shigella-specific antisera are not clinically significant.201020924038
bacterial enteropathogens and risk factors associated with childhood diarrhea.to investigate the etiology of bacterial enteropathogens causing diarrhea among children; to elucidate the risk factors, sign and symptoms involved in developing of infection; and to identify the antimicrobial susceptibility pattern.201020924718
[screening of harmine tolerance/degrading bacteria from camel rumen].peganum harmala, a famous traditional chinese drug, contains a variety of alkaloids and toxic for many animals. camels mainly live in desert or semi-desert areas, with the robust gastrointestine system in digesting various feed including toxic plants without disease symptoms.201020931866
viable but nonculturable state of foodborne pathogens in grapefruit juice: a study of laboratory.several foodborne human pathogens, when exposed to harsh conditions, enter viable but nonculturable (vbnc) state; however, still open is the question whether vbnc pathogens could be a risk for public health, because, potentially, they can resuscitate. moreover, cultural methods for food safety control were not able to detect vbnc forms of foodborne bacteria. particularly, it has not been established whether food chemophysical characteristics can induce vbnc state in contaminating pathogen bacter ...201020932087
sensitization of microcin j25-resistant strains by a membrane-permeabilizing peptide.microcin j25 (mccj25) is a plasmid-encoded, 21-amino-acid, antibacterial peptide produced by escherichia coli. mccj25 inhibits rna polymerase and the membrane respiratory chain. mccj25 uptake into e. coli-sensitive strains is mediated by the outer membrane receptor fhua and the inner membrane proteins tonb, exbb, exbd, and sbma. this peptide is active on some e. coli, salmonella, and shigella species strains, while other gram-negative bacteria, such as clinical isolates of enterobacter cloacae, ...201020802073
an outbreak of shigellosis due to shigella flexneri serotype 3a in a prison in iran.on june 16 and 17, 2007, the medical clinic of a prison in isfahan, iran received multiple reports of gastrointestinal illness among prisoners. a cross-sectional study was therefore undertaken to determine the extent, causative agent and possible source of the outbreak.201020804308
in silico characterization of shikimate kinase of shigella flexneri: a potential drug target.shigella flexneri is a major pathogen responsible for shigellosis causing massive morbidity among young population and imposes huge socio-economic burden. in this study, shikimate kinase (sk) from s. flexneri was characterized in silico and disordered regions were predicted. motifs and domains were calculated using computational tools. a three dimensional model of shikimate kinase of s.flexneri was constructed using shikimate kinase of e.coli (pdbid: 1kag_a) as template by comparative modeling a ...201020658341
[dysentery and amoebiasis in poland in 2008].the number as well as incidence rate of notified as shigellosis, bacillary dysentery cases in xxi century are every year lower. only 33 cases were notified in the year 2008 (incidence rate 0.09/100 000 population), while the 64 cases were notified in 2007 (incidence rate 0.17/100 000), but 35 (incidence rate 0.09) were notified in 2006 and median in the 2002-2006 years was 75 cases, incidence rate 0.2/100 000 population. since 2000 no one-death case was notified. several imported cases were noti ...201020731222
mass spectrometry biotyper system identifies enteric bacterial pathogens directly from colonies grown on selective stool culture media.we evaluated the performance and cost-effectiveness of a matrix-assisted laser desorption ionization time-of-flight mass spectrometry-based biotyper system for the routine identification of common enteric bacterial pathogens seen in middle tennessee from suspicious colonies grown on selective stool culture media. a total of 304 suspicious colonies were selected and further identified from 605 stool specimens. the suspicious colonies were analyzed by the biotyper system, and the results were comp ...201020844226
transmembrane bax inhibitor motif containing (tmbim) family proteins perturbs a trans-golgi network enzyme, gb3 synthase, and reduces gb3 biosynthesis.globotriaosylceramide (gb3) is a well known receptor for shiga toxin (stx), produced by enterohemorrhagic escherichia coli and shigella dysenteriae. the expression of gb3 also affects several diseases, including cancer metastasis and fabry disease, which prompted us to look for factors involved in its metabolism. in the present study, we isolated two cdnas that conferred resistance to stx-induced cell death in hela cells by expression cloning: ganglioside gm3 synthase and the cooh terminus regio ...201020837469
detection of airborne bacteria in a german turkey house by cultivation-based and molecular methods.today's large-scale poultry production with densely stocked and enclosed production buildings is often accompanied by very high concentrations of airborne microorganisms leading to a clear health hazard for employees working in such environments. depending on the expected exposure to microorganisms, work has to be performed under occupational safety conditions. in this study, turkey houses bioaerosols were investigated by cultivation-based and molecular methods in parallel to determine the conce ...201020720091
serum neopterin is elevated in patients infected with shigella.abstract:201020727206
prevalence of bacteria and parasites in white ibis in egypt.a field survey was conducted to evaluate the prevalence of bacterial infections among free-living white ibis (nipponia nippon) in which 92 bacterial isolates were recovered from 193 different internal organs of 55 apparently healthy ibis. escherichia coli and salmonella spp. were isolated at rates of 43.6% and 14.5%, respectively. the other bacterial pathogens isolated were shigella spp. (34.5%), enterobacter spp. (21.8%) citrobacter spp. (18.1%), klebsiella pneumonia (16.3), staphylococcus aure ...201020857378
lactoferrin increases both resistance to salmonella typhimurium infection and the production of antibodies in mice.lactoferrin (lf) is a multifunctional iron-binding glycoprotein with antibacterial and immunomodulatory activities. the antibacterial influence of orally administered bovine lf (blf) against murine infection caused by salmonella typhimurium (s. typhimurium) has scarcely been explored. in the current study, balb/c mice were treated orally for 7 days with either 5 or 100mg of bovine lactoferrin (blf). on day 7 of treatment, mice were intragastrically infected with a lethal or sublethal dose of col ...201020727369
medicinal potions used against infectious bowel diseases in mayan traditional medicine.since one of the main health problems of the indigenous population are infectious bowel diseases, we decided to test mayan medicinal potions used to treat these conditions against some of the causal agents.201020728517
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