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real-time multiplex pcr for simultaneous detection of campylobacter jejuni, salmonella, shigella and yersinia species in fecal samples.diarrheal diseases due to notifiable bacterial infections require rapid diagnosis of the causative pathogens. to facilitate detection, a real-time multiplex pcr was developed that identifies common diarrhea-causing bacteria in fecal samples. on the basis of published sequence data, sets of primers and probes were designed that were specific for campylobacter jejuni, salmonella, shigella/enteroinvasive escherichia coli eiec, and yersinia species, suitable for use in a one-tube pcr assay. the assa ...201121855409
global distribution of shigella sonnei clones.to investigate global epidemiology of shigella sonnei, we performed multilocus variable number tandem repeat analysis of 1,672 isolates obtained since 1943 from 50 countries on 5 continents and the pacific region. three major clonal groups were identified; 2 were globally spread. type 18 and its derivatives have circulated worldwide in recent decades.201122000369
intestinal parasitosis and shigellosis among diarrheal patients in gondar teaching hospital, northwest ethiopia.abstract:201122041102
antibacterial and anti-inflammatory activity of traditional chinese herb pairs, angelica sinensis and sophora flavescens.the purpose of the present study was to investigate the antibacterial and anti-inflammatory activity of angelica sinensis extract (ae), sophora flavescens extract (se), and herb pair a. sinensis and s. flavescens extract (hpe). endotoxin-induced uveitis (eiu) was induced in rats by a footpad injection of lipopolysaccharide. the anti-inflammatory potential of ae, se, and hpe in the regulation of nuclear factor kappa b (nf-κb), maleic dialdehyde (mda), polymorphonuclear cells (pmn), interleukin-1β ...201121976127
waterlogsy nmr experiments in conjunction with molecular-dynamics simulations identify immobilized water molecules that bridge peptide mimic mdwnmhaa to anticarbohydrate antibody sya/j6.x-ray crystallographic data of the carbohydrate mimic mdwnmhaa when bound to an anti-shigella flexneri y mab sya/j6 indicate the immobilization of water molecules, that is, the presence of "bound" waters, in the active site. water ligand observed via gradient spectroscopy (waterlogsy) was used in conjunction with saturation transfer difference (std)-nmr spectroscopy to probe the existence of immobilized water molecules in the complex of mdwnmhaa 1 bound to mab sya/j6. molecular dynamics simulati ...201121887835
[etiological surveillance and analysis of infectious diarrhea in beijing in year 2010].to explore the pathogenic form, epidemic features and serotype distribution of the pathogenic bacteria causing infectious diarrhea in beijing.201122177306
matrix-assisted laser desorption ionization-time of flight mass spectrometry for the identification of bacteria and yeasts in a clinical microbiological laboratory: a review.recently, maldi-tof ms devices designed for use in clinical laboratories have been commercially introduced in various large centres worldwide. all published studies conclude that maldi-tof ms can be implemented easily for routine identification of bacteria and yeasts in a clinical microbiological laboratory. although all data show that maldi-tof ms correctly identifies the great majority of isolates processed routinely, it cannot yet identify every such isolate. until today, maldi-tof ms is inap ...201121938981
structural segregation of gut microbiota between colorectal cancer patients and healthy volunteers.despite a long-suspected role in the development of human colorectal cancer (crc), the composition of gut microbiota in crc patients has not been adequately described. in this study, fecal bacterial diversity in crc patients (n=46) and healthy volunteers (n=56) were profiled by 454 pyrosequencing of the v3 region of the 16s ribosomal rna gene. both principal component analysis and unifrac analysis showed structural segregation between the two populations. forty-eight operational taxonomic units ...201121850056
Atypical Shigella boydii 13 encodes virulence factors seen in attaching and effacing Escherichia coli.Enterohemorrhagic E. coli (EHEC) is a foodborne pathogen that causes watery diarrhea and hemorrhagic colitis. In this study, we identified StcE, a secreted zinc metalloprotease that contributes to intimate adherence of EHEC to host cells, in culture supernatants of atypical Shigella boydii 13 (Shigella B13) strains. Further examination of the Shigella B13 strains revealed that this cluster of pathogens does not invade but forms pedestals on HEp-2 cells similar to EHEC and enteropathogenic E. col ...201122126649
social-economic factors and irrational antibiotic use as reasons for antibiotic resistance of bacteria causing common childhood infections in primary healthcare.the most prevalent childhood bacterial infections in primary healthcare are respiratory, gastrointestinal and urogenital infections. the main aim of this paper was to consider factors (socio-economic factors and irrational antibiotic use) that contribute to the development of bacterial resistance, as well as measures that resulted in a reduction of this problem. computerized search through the medline of published articles on antibiotic resistance from 1996 to 2011 in english or serbian was comp ...201121987082
Reactor performance and bacterial pathogen removal in response to sludge retention time in a mesophilic anaerobic digester treating sewage sludge.The effects of sludge retention time (SRT) on reactor performance and bacterial pathogen removal of sludge mesophilic anaerobic digestion (MAD) were investigated in a continuous stirred tank reactor. The average volatile solids removal remained around 20% and the biogas production rate varied from 100 to 132ml/ld. The MAD process was efficient to remove Salmonella sp. and Escherichia coli with removal efficiencies increased with SRT from 11d, 16d to 25d. However, the Shigella sp. removal was ins ...201122197074
analysis of synonymous codon usage in shigella flexneri 2a strain 301 and other shigella and escherichia coli strains.in this study, we analysed synonymous codon usage in shigella flexneri 2a strain 301 (sf301) and performed a comparative analysis of synonymous codon usage patterns in sf301 and other strains of shigella and escherichia coli. although there was a significant variety in codon usage bias among different sf301 genes, there was a slight but observable codon usage bias that could primarily be attributable to mutational pressure and translational selection. in addition, the relative abundance of dinuc ...201122112197
Ciprofloxacin-resistant Shigella sonnei among men who have sex with men, Canada, 2010.In 2010, we observed isolates with matching pulsed-field gel electrophoresis patterns from 13 cases of ciprofloxacin-resistant Shigella sonnei in Montréal. We report on the emergence of this resistance type and a study of resistance mechanisms. The investigation suggested local transmission among men who have sex with men associated with sex venues.201121888811
characterization of a vii-like phage specific to escherichia coli o157:h7.phage vb_ecom_cba120 (cba120), isolated against escherichia coli o157:h7 from a cattle feedlot, is morphologically very similar to the classic phage vii of salmonella enterica serovar typhi. until recently, little was known genetically or physiologically about the vii-like phages, and none targeting e. coli have been described in the literature. the genome of cba120 has been fully sequenced and is highly similar to those of both vii and the shigella phage ag3. the core set of structural and repl ...201121899740
Further characterization of Shigella sonnei live vaccine candidates WRSs2 and WRSs3-plasmid composition, invasion assays and Sereny reactions. 201121983066
Clinical characteristics and antibiotic resistance of Shigella gastroenteritis in Ankara, Turkey between 2003 and 2009, and comparison with previous reports.The aim of this study was to define the epidemiological, clinical, and antibiotic susceptibility patterns of Shigella gastroenteritis cases occurring during the years 2003-2009 and to compare results with those of the years 1987-2002.201121982814
convergent synthesis of the tetrasaccharide repeating unit of the o-antigen of shigella boydii type 9.a convenient synthesis of the tetrasaccharide repeating unit of the o-antigen of shigella boydii type 9 has been achieved in excellent yield using a [2 + 2] block glycosylation strategy. tempo-mediated selective oxidation of the primary alcohol of the tetrasaccharide derivative 8 to the carboxylic group followed by deprotection of the functional groups furnished target tetrasaccharide 1 as its 4-methoxyphenyl glycoside in high yield.201121977201
synthesis of novel quinoxalinone derivatives by conventional and microwave methods and assessing their biological activity.in this study, twenty-one arylaminoquinoxalinone derivatives were synthesized and their antibacterial activities against staphylococci aureus, pseudomonas aureus, escherichia coli, bacillus subtilis, salmonella typhi, and shigella pneumoniae were evaluated relative to known antibiotics; augmentin, ampicillin, and chloramphenicol. the insecticidal activities of the prepared compounds were also investigated against tribolium castaneum using permethrin as a standard insecticide. the derivatives wer ...201122076760
the role of oxyr and soxrs in oxidative stress survival in shigella flexneri.shigella flexneri, a facultative intracellular pathogen, is exposed to a variety of environments inside and outside of the human host. some of these environments may contain significant oxidative stress. s. flexneri mutants were generated with deletions in the major oxidative stress regulators oxyr and/or soxrs to test their importance in shigella biology. strains that contained a deletion of oxyr had reduced growth and survival during aerobic growth, but not microaerobic growth. the mutants wer ...201122015257
live attenuated shigella dysenteriae type 1 vaccine strains overexpressing shiga toxin b subunit.shigella dysenteriae serotype 1 (s. dysenteriae 1) is unique among the shigella species and serotypes in the expression of shiga toxin which contributes to more severe disease sequelae and the ability to cause explosive outbreaks and pandemics. s. dysenteriae 1 shares characteristics with other shigella species, including the capability of causing clinical illness with a very low inoculum (10 to 100 cfu) and resistance to multiple antibiotics, underscoring the need for efficacious vaccines and t ...201121969003
Comparative evaluation of the antibody in lymphocyte supernatant (ALS) and enzyme-linked immunospot (ELISPOT) assays for measuring mucosal immune responses to Shigella antigens.Accurately assessing mucosal immune responses to candidate vaccines remains a technical challenge. ELISPOT is widely used as a surrogate of mucosal immune response by directly enumerating circulating antibody secreting cells (ASCs), while antibody in lymphocyte supernatant (ALS) titers the total amount of antibody secreted by ASC ex vivo using ELISA. ALS is more practical than ELISPOT because the ASC supernatant is frozen for ELISA that can be conducted at any time, with any antigen, and in any ...201121939714
a school outbreak of shigella sonnei infection in china: clinical features, antibiotic susceptibility and molecular epidemiology.objective: to describe the clinical features of infection, and the antibiotic susceptibility of epidemic strains, and investigate plasmid maps and integrons of the isolates from an outbreak of shigella sonnei infection at an elementary school in southwest china. study design: cross-sectional study. setting: an elementary school and five hospitals in chengdu in southwest china. results: there were 1,134 students in the school. 937 (82.6%) students had signs and symptoms. of the 568 (60.6%, 568/93 ...201121992857
Evolutionary and functional insights into Leishmania META1: evidence for lateral gene transfer and a role for META1 in secretion.ABSTRACT: BACKGROUND: Leishmania META1 has for long been a candidate molecule for involvement in virulence: META1 transcript and protein are up-regulated in metacyclic Leishmania. Yet, how META1 contributes to virulence remains unclear. We sought insights into the possible functions of META1 by studying its evolutionary origins. RESULTS: Using multiple criteria including sequence similarity, nucleotide composition, phylogenetic analysis and selection pressure on gene sequence, we present evide ...201122093578
A new piece of the Shigella pathogenicity puzzle: spermidine accumulationby silencing of the speG gene.The genome of Shigella, a gram negative bacterium which is the causative agent of bacillary dysentery, shares strong homologies with that of its commensal ancestor, Escherichia coli. The acquisition, by lateral gene transfer, of a large plasmid carrying virulence determinants has been a crucial event in the evolution towards the pathogenic lifestyle and has been paralleled by the occurrence of mutations affecting genes, which negatively interfere with the expression of virulence factors. In this ...201122102881
topological characterisation and identification of critical domains within glucosyltransferase iv (gtriv) of shigella flexneri.abstract:201122188643
The effects of solid media type on routine identification of bacterial isolates using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry.Background: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis is a rapid method for the identification of bacteria based upon the comparison of protein profiles. Factors that may alter profiles include culture conditions and presence of exogenous substances and could hinder identification. Methods: Bacterial isolates identified using conventional methods were cultured on various media and identified using the MALDI Biotyper system (Bruker Dalton ...201122162546
[Dysentery and amoebiasis in Poland in 2009].Only 30 cases were notified (incidence rate 0.08/100 000 population) in the year 2009, while the 33 cases were notified in 2008 (incidence rate 0.09/100 000), and median in the 2003-2007 years was 74 cases, incidence rate 0.19/100 000 population. Since 2000 no one-death case was notified. In the period of low frequency of Shigella infections, the external quality assessment control of the quality of bacteriological media, laboratory and prae-laboratory procedures for detection of different Shige ...201121913464
The scope of phage display for membrane proteins.Numerous examples of phage display applied to soluble proteins demonstrate the power of the technique for protein engineering, affinity reagent discovery and structure-function studies. Recent reports have expanded phage display to include membrane proteins (MPs). The scope and limitations of MP display remain undefined. Therefore, we report data from the phage display of representative types of membrane-associated proteins including plasma, nuclear, peripheral, single and multipass. The periphe ...201122037583
reflectron maldi tof and maldi tof/tof mass spectrometry reveal novel structural details of native lipooligosaccharides.lipooligosaccharides (los) are powerful gram-negative glycolipids that evade the immune system and invade host animal and vegetal cells. the structural elucidation of los is pivotal to understanding the mechanisms of infection at the molecular level. the amphiphilic nature of los has been the main obstacle for structural analysis by matrix-assisted laser desorption/ionization (maldi) mass spectrometry (ms). our approach has resolved this important issue and has permitted us to obtain reflectron ...201122124985
Misidentification of a commensal inactive Escherichia coli as Shigella sonnei by an automated system in a critically ill patient.Though automated identification and sensitivity testing has established itself as a standard in many high throughput clinical microbiology laboratories, misidentification by the automated systems can also happen.201122029193
recombinant shiga toxin b subunit elicits protection against shiga toxin via mixed th type immune response in mice.shigella dysenteriae is the causative agent of the third commonest bacterial disease for childhood diarrhoea and responsible for millions of deaths per year. it produces potent toxin termed shiga toxin which is listed in category b biological warfare agent of cdc, usa. earlier we have reported production of recombinant shiga toxin b subunit that produced antibodies which neutralized shiga toxin toxicity in hela cells. in the present study, we have evaluated the immunomodulatory potential of rstx ...201121856355
Acid-bile, antibiotic resistance and inhibitory properties of propionibacteria isolated from Turkish traditional home-made cheeses.In this study, a total of 29 Propionibacterium spp. were isolated from traditional home-made Turkish cheese samples. As a result of the identification, isolates were identified as Propionibacterium freudenreichii subsp. freudenreichii (15 strains), Propionibacterium jensenii (12), and Propionibacterium thoenii (2). All isolates and 5 reference strains were examined for their abilities to survive at pH 2.0, 3.0, 4.0, 5.0 and in the presence of 0.06, 0.15 and 0.30% bile salts, their influence on t ...201122019987
Prevalence and antimicrobial susceptibility of major foodborne pathogens in imported seafood.Seafood is a leading commodity implicated in foodborne disease outbreaks in the United States. Seafood importation rose dramatically in the past 3 decades and now contributes to more than 80% of the total U.S. seafood supply. However, limited data are available on the microbiological safety of imported seafood. In this study, we obtained a total of 171 salmon, shrimp, and tilapia samples imported from 12 countries in three retail stores in Baton Rouge, LA. The total microbial population and the ...201121902913
a broadly protective shigella vaccine based on type iii secretion apparatus proteins.shigella ssp. are food and water-borne pathogens that cause severe diarrheal and dysenteric disease associated with high morbidity and mortality. individuals most often affected are children under 5 years of age in the developing world. the existence of multiple shigella serotypes and the heterogenic distribution of pathogenic strains as well as emerging antibiotic resistance require the development of a broadly protective vaccine. all shigella ssp. utilize a type iii secretion system (ttss) to ...201122202122
up-regulation of muc2 and il-1β expression in human colonic epithelial cells by shigella and its interaction with mucins.the entire gastrointestinal tract is protected by a mucous layer, which contains complex glycoproteins called mucins. muc2 is one such mucin that protects the colonic mucosa from invading microbes. the initial interaction between microbes and mucins is an important step for microbial pathogenesis. hence, it was of interest to investigate the relationship between host (mucin) and pathogen interaction, including shigella induced expression of muc2 and il-1β during shigellosis.201122073249
Detection of diarrhoeal pathogens in human faeces using an automated, robotic platform.Infectious diarrhoeal diseases represent a major socio-economic burden to humans, and are linked to a range of pathogens, including viruses, bacteria and protists. The accurate detection of such pathogens is central to control. However, detection often relies on methods that have limited diagnostic sensitivity and specificity. Here, we assessed an automated, robotic platform for the simultaneous detection of eight major pathogens associated with infectious diarrhoea. Genomic DNA samples (n = 167 ...201122056326
Genotyping of selected bacterial enteropathogens in Norway.In Norway the Norwegian Institute of Public Health (NIPH) is the primary facility for nationwide surveillance of foodborne infections, and it is vital that we can perform rapid and high resolution identification of foodborne bacteria at the strain level. During the last decade a rapid introduction of DNA-based methods has been introduced, which show promise in enhancing the speed and discriminatory capability of the typing laboratory. The laboratory responsible for genotyping enteropathogens at ...201121975141
Third-generation cephalosporin resistance in clinical isolate of Shigella sonnei in Andaman & Nicobar Islands, India. 201121918310
Differential host immune responses to epidemic and endemic strains of Shigella dysenteriae type I.Shigella dysenteriae type 1 causes devastating epidemics in developing countries with high case-fatality rates in all age-groups. The aim of the study was to compare host immune responses to epidemic (T2218) and endemic strains of S. dysenteriae type 1. Shigellacidal activity of serum from rabbits immunized with epidemic or endemic strains, S. dysenteriae type 1-infected patients, and healthy adult controls from Shigella-endemic and non-endemic regions was measured. Immunogenic cross-reactivity ...201122106748
outbreak of shigella sonnei infection in norway linked to consumption of fresh basil, october 2011.we report a shigella sonnei outbreak of 46 cases that occurred in norway during october 2011. two municipalities were involved. a large cluster (42 cases)was concentrated in north norway, while a smallcluster (4 cases) occurred in the south-east region.epidemiological evidence and trace back investigations have linked the outbreak to the consumption of imported fresh basil. the product has been withdrawn from the market. no further cases have been reported since 25 october.201122085618
prevalence and antimicrobial susceptibility patterns of shigella species at felege hiwot referral hospital, northwest ethiopia.shigella species infections coupled with increased levels of antimicrobial resistances are major public health problems in developing countries particularly in children.201121991758
foodborne-associated shigella sonnei, india, 2009 and 2010. 201122099103
evolutionary silence of the acid chaperone protein hdeb in enterohemorrhagic escherichia coli o157:h7.the periplasmic chaperones hdea and hdeb are known to be important for cell survival at low ph (ph<3) in escherichia coli and shigella spp. here we investigated the roles of hdea and hdeb in the survival of various enterohemorrhagic e. coli (ehec) following exposure to ph 2.0. similar to k-12 strains, the acid protections conferred by hdea and hdeb in ehec o145 were significant: loss of hdea and hdeb led to over 100- to 1000-fold reductions in acid survival, depending on the growth condition of ...201122179243
rational design of an artificial genetic switch: co-option of the h-ns-repressed prou operon by the virb virulence master regulator.the h-ns protein represses the transcription of hundreds of genes in gram-negative bacteria. derepression is achieved by a multitude of mechanisms, many of which involve the binding of a protein to dna at the repressed promoter in a manner that compromises the maintenance of the h-ns-dna nucleoprotein repression complex. the principal virulence gene promoters in shigella flexneri, the cause of bacillary dysentery, are repressed by h-ns. virb, a protein that closely resembles members of the parb ...201121873493
Crystal Structure of the VapBC Toxin-Antitoxin Complex from Shigella flexneri Reveals a Hetero-Octameric DNA-Binding Assembly.Toxin-antitoxin (TA) loci are common in archaea and prokaryotes and allow cells to rapidly adapt to changing environmental conditions through release of active regulators of metabolism. Many toxins are endonucleases that target cellular mRNA and tRNAs, while the antitoxins tightly wrap around the toxins to inhibit them under normal circumstances. The antitoxins also bind to operators in the promoter regions of the cognate TA operon and thereby regulate transcription. For enteric vapBC TA loci, t ...201122037005
applications of pcr (real-time and masstag) and enzyme-linked immunosorbent assay in diagnosis of respiratory infections and diarrheal illness among deployed u.s. military personnel during exercise balikatan 2009, philippines.laboratory-based surveillance for diarrheal and respiratory illness was conducted at the 2009 republic of the philippines-united states balikatan exercise to determine the presence of specific pathogens endemic in the locations where the military exercises were conducted. ten stool and 6 respiratory specimens were obtained from individuals meeting case definitions for diarrhea or respiratory illness. stool specimens were frozen in dry ice and remotely tested using enzyme-linked immunosorbent ass ...201122128641
the inhibitory activity of lactobacillus spp. isolated from breast milk on gastrointestinal pathogenic bacteria of nosocomial origin.milk acts as a mean for transporting many essential substances from the mother to the child. in human beings, milk includes several predominant bacteria, such as staphylococci, streptococci, micrococci, lactobacilli, enterococci, lactococci and bifidobacteria. besides, its intake favors the predominance of bifidobacteria and lactobacilli in the child's intestinal microbiota. the present work explores the isolation and selection of lactobacilli strains with probiotic potential, focusing in their ...201121846506
comparative genomic analysis of bacteriophage ep23 infecting shigella sonnei and escherichia coli.bacteriophage ep23 that infects escherichia coli and shigella sonnei was isolated and characterized. the bacteriophage morphology was similar to members of the family siphoviridae. the 44,077 bp genome was fully sequenced using 454 pyrosequencing. comparative genomic and phylogenetic analyses showed that ep23 was most closely related to phage so-1, which infects sodalis glossinidius and phage ssl-2009a, which infects engineered e. coli. genomic comparison indicated that ep23 and so-1 were very s ...201122203555
[Antimicrobial resistance profiles of Shigella spp. isolated from feces samples in Hacettepe University Ihsan Dogramaci Children's Hospital between 1999-2010].The symptoms of infections caused by Shigella spp. are diverse and may change from person to person. The choice of antibiotics as well as the prevention of the loss of fluid and electrolytes are important in the clinical recovery. The local resistance rates to antibiotics should be taken into consideration when planning empirical therapy. The aims of this retrospective study were to detect the in vitro antimicrobial susceptibility of 605 Shigella spp. strains isolated from feces samples of child ...201122090291
site-specific incorporation of photo-cross-linker and bioorthogonal amino acids into enteric bacterial pathogens.enteric bacterial pathogens are known to effectively pass through the extremely acidic mammalian stomachs and cause infections in the small and/or large intestine of human hosts. however, their acid-survival strategy and pathogenesis mechanisms remain elusive, largely due to the lack of tools to directly monitor and manipulate essential components (e.g., defense proteins or invasive toxins) participating in these processes. herein, we have extended the pyrrolysine-based genetic code expansion st ...201122084898
cloning, characterization and evaluation of potent inhibitors of shigella sonnei acetohydroxyacid synthase catalytic subunit.acetohydroxyacid synthase (ahas) is a thiamin diphosphate (thdp)- and flavin adenine dinucleotide (fad)-dependent plant and microbial enzyme that catalyzes the first common step in the biosynthesis of essential amino acids such as leucine, isoleucine and valine. to identify strong potent inhibitors against shigella sonnei (s. sonnei) ahas, we cloned and characterized the catalytic subunit of s. sonnei ahas and found two potent chemicals (khg20612, khg25240) that inhibit 87-93% s. sonnei ahas act ...201122015678
systematic review: the use of proton pump inhibitors and increased susceptibility to enteric infection.background: the use of proton pump inhibitors (ppis) is increasing worldwide. suppression of gastric acid alters the susceptibility to enteric bacterial pathogens. aim  this systematic review was undertaken to examine the relationship between ppi use and susceptibility to enteric infections by a specific pathogen based on published literature and to discuss the potential mechanisms of ppi enhanced pathogenesis of enteric infections. methods  pubmed, ovid medline databases were searched. search t ...201121999643
liver mass in a young adult. 201121943702
shigella flexneri infection generates the lipid pi5p to alter endocytosis and prevent termination of egfr signaling.the phosphoinositide metabolic pathway, which regulates cellular processes implicated in survival, motility, and trafficking, is often subverted by bacterial pathogens. shigella flexneri, a bacterium that causes dysentery, injects ipgd, a phosphoinositide phosphatase that generates the lipid phosphatidylinositol 5-phosphate (pi5p), into host cells, thereby activating the phosphoinositide 3-kinase-akt survival pathway. we show that epidermal growth factor receptor (egfr) is required for pi5p-depe ...201121934107
genomic characterization of enteroaggregative escherichia coli from children in mali.background. enteroaggregative escherichia coli (eaec) is a cause of epidemic and sporadic diarrhea, yet its role as an enteric pathogen is not fully understood. methods. we characterized 121 eaec strains isolated in 2008 as part of a case-control study of moderate to severe acute diarrhea among children 0-59 months of age in bamako, mali. we applied multiplex polymerase chain reaction and comparative genome hybridization to identify potential virulence factors among the eaec strains, coupled wit ...201122184729
antagonistic bacteria from live corals, tuticorin coastal waters, southeastern india.the objective of this study is to isolate and production of secondary metabolites with bioactive substances by coral reef (acropora formosa and favia palida) associated bacteria was carried out from the tuticorin coastal waters, southeastern india. the isolated coral associated bacteria were found to have an antagonistic effect against 10 human pathogens. the pathogens were escherichia coli, shigella dysentriae, staphylococcus epidermidis, s. aureus, klebsiella pneumoniae, pseudomonas aerogenosa ...201121454167
[invasive gastroenteritis, anything new?].invasive gastroenteritis is characterized by fever and inflammatory diarrhea and can be caused by nontyphoideal salmonella serotypes and shigella spp.-enteroinvasive escherichia coli (eiec), among other pathogens. this review describes emerging monophasic variants of salmonella enterica serotype 1,4,[5],12:i:- and provides an evolutionary consideration of shigella spp.-eiec as a single pathotype. in 1997, a monophasic variant of s. enterica serotype 1,4,[5],12:i:-, phage-type u302, multidrug res ...201121458713
vinculin activators target integrins from within the cell to increase melanoma sensitivity to chemotherapy.metastatic melanoma is an aggressive skin disease for which there are no effective therapies. emerging evidence indicates that melanomas can be sensitized to chemotherapy by increasing integrin function. current integrin therapies work by targeting the extracellular domain, resulting in complete gains or losses of integrin function that lead to mechanism-based toxicities. an attractive alternative approach is to target proteins, such as vinculin, that associate with the integrin cytoplasmic doma ...201121460181
autophagy and the cytoskeleton: new links revealed by intracellular pathogens.actin-based motility is used by various pathogens such as listeria and shigella for dissemination within cells: and tissues, yet host factors counteracting this process have not been identified. we have recently discovered that infected host cells can prevent actin-based motility of shigella by compartmentalizing bacteria inside 'septin cages,' revealing a novel mechanism of host defense that restricts dissemination. because bacterial proteins controlling actin-based motility also regulate the a ...201121464614
antimicrobial activity against shigella sonnei and probiotic properties of wild lactobacilli from fermented food.four lactobacilli strains (lactobacillus paracasei subp. paracasei m5-l, lactobacillus rhamnosus j10-l, lactobacillus casei q8-l and l. rhamnosus gg (lgg), were systematically assessed for the production of antimicrobial substances active towards shigella sonnei, escherichia coli and salmonella typhimurium. agar-well assay showed that the four lactobacilli strains displayed strong antibacterial activity towards s. sonnei. the nature of antimicrobial substances was also investigated and shown to ...201121466951
assessment of the antibacterial activity and the antidiarrheal function of flavonoids from bayberry fruit.chinese bayberry fruits are used as a folk medicine to cure diarrhea. however, the active compounds have not yet been reported. we found that bayberry fruit extract showed significant antibacterial activity against salmonella, listeria, and shigella, and the minimal inhibitory concentration (mic) ranged from 2.07 to 8.28 mg/ml. positive relationships were found between the antibacterial activity and the total polyphenol (r = 0.88) and flavonoid contents (r = 0.92) of samples using different extr ...201121469731
genetic diversity and antibiotic resistance in shigella dysenteriae and shigella boydii strains isolated from children aged <5 years in egypt.summarydiversity within shigella dysenteriae (n=40) and shigella boydii (n=30) isolates from children living in egypt aged <5 years was investigated. shigella-associated diarrhoea occurred mainly in summer months and in children aged <3 years, it commonly presented with vomiting and fever. serotypes 7 (30%), 2 (28%), and 3 (23%) accounted for most of s. dysenteriae isolates; 50% of s. boydii isolates were serotype 2. s. dysenteriae and s. boydii isolates were often resistant to ampicillin, chlor ...201121470441
new developments in traveler's diarrhea.traveler's diarrhea (td) is a crucial area for research, as it affects millions of tourists each year and creates a large economic burden. more than 60% of td cases are caused by a variety of bacterial enteropathogens: diarrhea-producing escherichia coli, shigella, campylobacter, salmonella, aeromonas, plesiomonas, and noncholera vibrios. noroviruses are also an important cause of morbidity among travelers. recent studies have identified host genetic risk factors associated with susceptibility t ...201121475415
behavior of salmonella typhimurium, staphylococcus aureus, listeria monocytogenes, and shigella flexneri and shigella sonnei during production of pulque, a traditional mexican beverage.pulque is a typical fermented alcoholic beverage of central mexico, produced from the nectar of maguey agave plants. production systems are largely artisanal, with inadequate hygiene conditions and exposure to multiple contamination sources. no data exist on pulque microbiological safety and the behavior of pathogenic microorganisms in agave nectar and pulque. an initial trial was done of the behavior of salmonella typhimurium, staphylococcus aureus, listeria monocytogenes, and shigella flexneri ...201121477472
dissemination of ndm-1 positive bacteria in the new delhi environment and its implications for human health: an environmental point prevalence study.not all patients infected with ndm-1-positive bacteria have a history of hospital admission in india, and extended-spectrum β-lactamases are known to be circulating in the indian community. we therefore measured the prevalence of the ndm-1 gene in drinking water and seepage samples in new delhi.201121478057
corn flake-like morphology of iron nanoparticles and its antibacterial property. 201121478648
an integrated approach for finding overlooked genes in shigella.the completion of numerous genome sequences introduced an era of whole-genome study. however, many genes are missed during genome annotation, including small rnas (srnas) and small open reading frames (sorfs). in order to improve genome annotation, we aimed to identify novel srnas and sorfs in shigella, the principal etiologic agents of bacillary dysentery.201121483688
phytochemical screening and antibacterial activities of vernonia ambigua, vernonia blumeoides and vernonia oocephala (asteraceae).some vernonia species (vernonia ambigua, vernonia blumeoides and vernonia oocephala) used in northern nigerian traditional medicine, were subjected to phytochemical screening using standard procedures. the antibacterial activity using the disc diffusion method as outlined by the nccls was carried out on klebsiella pneumoniae, streptococcus pyogenes, staphylococcus aureus, corynbacterium ulcerans, methicillin resistant staphylococcus aureus (mrsa), salmonella typhi, pseudomonas aeruginosa, shigel ...201121485703
outbreak of shigella sonnei infections in the orthodox jewish community of antwerp, belgium, april to august 2008.in the beginning of april 2008 three cases of shigella sonnei infection were identified among the orthodox jewish community of antwerp, belgium. we conducted a descriptive study and a household cohort study to identify potential risk factors. stool samples were cultured and antibiotic susceptibility of the isolates was determined. between april and august 2008, 42 cases were registered. all characterised isolates (n=20) shared an identical pulsed-field gel electrophoresis profile and were indist ...201121492526
zidovudine (azt) has a bactericidal effect on enterobacteria and induces genetic modifications in resistant strains.the spread of multiresistant bacteria increases the need for new antibiotics. the observation that some nucleoside analogues have antibacterial activity led us to further investigate the antimicrobial activity and resistance of zidovudine (azt). we determined the minimum inhibition concentration (mic), studied time-kill curves, induced resistant bacteria and sequenced the gene for thymidine kinase. we demonstrate that azt has a bactericidal effect on some enterobacteria. however, azt could induc ...201121494911
microbiological quality of grey-mullet roe.the greek grey-mullet roe is produced from the fully developed gonads of the female mullet (mugil cephalus) couth in lagoons during their reproductive migration. the traditional processing method of the roe includes, air drying, salting, shape formation and covering with multiple layers of natural beeswax for preservation and distribution. fish roe brands have been a staple in local diet and is increasingly becoming popular in the international market. as a ready-to-eat food it's microbial quali ...201121497664
a unique arabinose 5-phosphate isomerase found within a genomic island associated with the uropathogenicity of escherichia coli cft073.previous studies showed that deletion of genes c3405 to c3410 from pai-metv, a genomic island from escherichia coli cft073, results in a strain that fails to compete with wild-type cft073 after a transurethral cochallenge in mice and is deficient in the ability to independently colonize the mouse kidney. our analysis of c3405 to c3410 suggests that these genes constitute an operon with a role in the internalization and utilization of an unknown carbohydrate. this operon is not found in e. coli k ...201121498648
shigella targets t cells.using a syringe-like device, shigella delivers an array of virulence factors into host cells to facilitate bacterial colonization and disable the host's innate immune defense. in this issue of cell host & microbe, konradt and colleagues (konradt et al., 2011) show that shigella also subverts adaptive immunity by targeting t cells through a mechanism involving pip(2) breakdown.201121501822
the shigella flexneri type three secretion system effector ipgd inhibits t cell migration by manipulating host phosphoinositide metabolism.shigella, the gram-negative enteroinvasive bacterium that causes shigellosis, relies on its type iii secretion system (ttss) and injected effectors to modulate host cell functions. however, consequences of the interaction between shigella and lymphocytes have not been investigated. we show that shigella invades activated human cd4(+) t lymphocytes. invasion requires a functional ttss and results in inhibition of chemokine-induced t cell migration, an effect mediated by the ttss effector ipgd, a ...201121501826
enteric virulence associated protein vapc inhibits translation by cleavage of initiator trna.eukaryotic pin (pilt n-terminal) domain proteins are ribonucleases involved in quality control, metabolism and maturation of mrna and rrna. the majority of prokaryotic pin-domain proteins are encoded by the abundant vapbc toxin-antitoxin loci and inhibit translation by an unknown mechanism. here we show that enteric vapcs are site-specific endonucleases that cleave trna(fmet) in the anticodon stem-loop between nucleotides +38 and +39 in vivo and in vitro. consistently, vapc inhibited translation ...201121502523
evaluation of low-copy genetic targets for waterborne bacterial pathogen detection via qpcr.recent developments in water quality research have highlighted difficulties in accurately predicting the incidence of pathogens within freshwater based on the viability, culturability and metabolic activity of indicator organisms. qpcr-driven assays are candidates to replace standard culture-based methods, however, protocols suitable for routine use have yet to be sufficiently validated. the objective of this study was to evaluate five oligonucleotide primers sets (etir, sinv, exot, vs1 and ipah ...201121514618
functional domains and motifs of bacterial type iii effector proteins and their roles in infection.a key feature of the virulence of many bacterial pathogens is the ability to deliver effector proteins into eukaryotic cells via a dedicated type three secretion system (t3ss). many bacterial pathogens, including species of chlamydia, xanthomonas, pseudomonas, ralstonia, shigella, salmonella, escherichia and yersinia, depend on the t3ss to cause disease. t3ss effectors constitute a large and diverse group of virulence proteins that mimic eukaryotic proteins in structure and function. a salient f ...201121517912
a novel vinculin binding site of the ipaa invasin of shigella.internalization of shigella into host epithelial cells, where the bacteria replicates and spreads to neighboring cells, requires a type 3 secretion system (t3ss) effector coined ipaa. ipaa binds directly to and activates the cytoskeletal protein vinculin after injection in the host cell cytosol and heretofore this was thought to be directed by two amphipathic α-helical vinculin binding sites (vbs) found in the c-terminal tail domain of ipaa. here we report a third vbs, ipaa-vbs3, that is located ...201121525010
synthesis, antibacterial activity and quantum-chemical studies of novel 2-arylidenehydrazinyl-4-arylthiazole analogues.a new series of 2-arylidenehydrazinyl-4-arylthiazole derivatives (2a-k) was designed and synthesized through a rapid, simple, and efficient methodology in excellent isolated yield. these compounds were screened for in vitro antimicrobial activities against eight bacteria, e.g. bacillus cereus, staphylococcus aureus, bacillus subtilis, bacillus megaterium, pseudomonas aeruginosa, shigella dysenteriae, salmonella typhi, escherichia coli, and three fungi e.g. aspergillus oryzae, candida albicans, a ...201121532194
synthesis, characterization and in vitro antimicrobial evaluation of new compounds incorporating oxindole nucleus.new compounds incorporating with the oxindole nucleus were synthesized via the reaction of substituted isatins [5-methyl-, 5-chloro- and 1-hydroxymethyl isatins] with different nucleophiles. the structures of the newly compounds were elucidated on the basis of ftir, (1)h nmr, (13)cmr spectral data, gc/ms and chemical analysis. investigation of antimicrobial activity of the new compounds was evaluated using broth dilution technique in terms of minimal inhibitory concentration (mic) count against ...201121534861
synthesis, characterization and biological studies of sulfonamide schiff's bases and some of their metal derivatives.a new series of schiff base ligands derived from sulfonamide and their metal(ii) complexes [cobalt(ii), copper(ii), nickel(ii) and zinc(ii)] have been synthesized and characterized. the nature of bonding and structure of all the synthesized compounds has been explored by physical, analytical and spectral data of the ligands and their metal(ii) complexes. the authors suggest that all the prepared complexes possess an octahedral geometry. the ligands and metal(ii) complexes have been screened for ...201121534864
fabrication of silver nanoparticles doped in the zeolite framework and antibacterial activity.using the chemical reduction method, silver nanoparticles (ag nps) were effectively synthesized into the zeolite framework in the absence of any heat treatment. zeolite, silver nitrate, and sodium borohydride were used as an inorganic solid support, a silver precursor, and a chemical reduction agent, respectively. silver ions were introduced into the porous zeolite lattice by an ion-exchange path. after the reduction process, ag nps formed in the zeolite framework, with a mean diameter of about ...201121383858
antigen-specific iga b memory cell responses to shigella antigens elicited in volunteers immunized with live attenuated shigella flexneri 2a oral vaccine candidates.we studied the induction of antigen-specific iga memory b cells (b(m)) in volunteers who received live attenuated shigella flexneri 2a vaccines. subjects ingested a single oral dose of 10(7), 10(8) or 10(9) cfu of s. flexneri 2a with deletions in guaba (cvd 1204) or in guaba, set and sen (cvd 1208). antigen-specific serum and stool antibody responses to lps and ipa b were measured on days 0, 7, 14, 28 and 42. iga b(m) cells specific to lps, ipa b and total iga were assessed on days 0 and 28. we ...201121388888
postinfective bile acid malabsorption: is this a long-term condition?postinfective bile acid malabsorption comprises a group of patients with a history of an episode of acute gastroenteritis triggering chronic diarrhoea. we identified these patients retrospectively from our medical records and assessed their long-term clinical course.201121389860
a candidate approach implicates the secreted salmonella effector protein spvb in p-body disassembly.p-bodies are dynamic aggregates of rna and proteins involved in several post-transcriptional regulation processes. p-bodies have been shown to play important roles in regulating viral infection, whereas their interplay with bacterial pathogens, specifically intracellular bacteria that extensively manipulate host cell pathways, remains unknown. here, we report that salmonella infection induces p-body disassembly in a cell type-specific manner, and independently of previously characterized pathway ...201121390246
structural elucidation of the o-antigen of the shigella flexneri provisional serotype 88-893: structural and serological similarities with s. flexneri provisional serotype y394 (1c).the structure of the repeating unit of the o-antigen polysaccharide from shigella flexneri provisional serotype 88-893 has been determined. (1)h and (13)c nmr spectroscopy as well as 2d nmr experiments were employed to elucidate the structure. the carbohydrate part of the hexasaccharide repeating unit is identical to the previously elucidated structure of the o-polysaccharide from s. flexneri prov. serotype y394. the o-antigen of s. flexneri prov. serotype 88-893 carries 0.7 mol o-acetyl group p ...201121392735
shigella flexneri type iii secreted effector ospf reveals new crosstalks of proinflammatory signaling pathways during bacterial infection.shigella flexneri type iii secreted effector ospf harbors a phosphothreonine lyase activity that irreversibly dephosphorylates map kinases (mapks) p38 and erk in infected epithelial cells and thereby, dampens innate immunity. whereas this activity has been well characterized, the impact of ospf on other host signaling pathways that control inflammation was unknown. here we report that ospf potentiates the activation of the mapk jnk and the transcription factor nf-?b during s. flexneri infection. ...201121402152
etiology of diarrhea in young children and patterns of antibiotic resistance in cambodia.little is known about diarrhea etiology and antibiotic resistance in developing countries where diarrhea is a major public health problem.201121412204
new insights into vinculin function and regulation.vinculin is a cytoplasmic actin-binding protein enriched in focal adhesions and adherens junctions that is essential for embryonic development. much is now known regarding the role of vinculin in governing cell-matrix adhesion. in the past decade that the crystal structure of vinculin and the molecular details for how vinculin regulates adhesion events have emerged. the recent data suggests a critical function for vinculin in regulating integrin clustering, force generation, and strength of adhe ...201121414589
antibacterial activity of the enniatin b, produced by fusarium tricinctum in liquid culture, and cytotoxic effects on caco-2 cells.the enniatins (ens) are bioactive compounds of hexadepsipeptidic structure produced by several strains of fusarium sp. the en b was purified from extracts of fusarium tricinctum growth on liquid culture of potato dextrose broth (pdb), using a semipreparative liquid chromatography (lc) followed by an analytical lc. the purity and the structure of the isolated compound were confirmed by the determination of the extinction coefficient and with electrospray ionization-mass spectrometry (esi-ms) stud ...201121417626
synthesis and in vitro microbiological evaluation of novel diethyl 6,6'-(1,4-phenylene)bis(4-aryl-2-oxo-cyclohex-3-enecarboxylates).novel bis cyclohexenone ester derivatives 14-19 were synthesized and characterized by their spectral data. in vitro microbiological evaluations were carried out for all the novel compounds 14-19 against clinically isolated bacterial and fungal strains. compounds 15, 16, 18 against staphylococcus aureus, 14, 15 against ß-haemolytic streptococcus, 15, 19 against micrococcus luteus, 17, 18 against salmonella typhii, 14, 17 against shigella flexneri, 15 against escherichia coli, 16 against pseudomon ...201121417963
evaluation of antidiarrheal and in vitro antiprotozoal activities of extracts of leaves of alocasia indica.alocasia indica schott (araceae) is used in several regions of india, especially in rural communities, by traditional medicine practitioners to treat diarrhea. however, no scientific data are available to justify the traditional potentials of the plant species in gastrointestinal disorders.201121428863
diarrheagenic escherichia coli in acute gastroenteritis in infants in north-west italy.enteropathogenic escherichia coli may cause diarrhoea in infancy, but it is not routinely detected and regarded as a major causative agent. the aim of the present study was to estimate the incidence of enteropathogenic e. coli infection and to investigate its epidemiology and pathogenesis from faecal specimens in infants hospitalized for acute gastroenteritis. between march 2008 and june 2009, faecal samples were collected and examined to recognize diarrhoeal aetiology, especially for e. coli, b ...201121344146
age specific aetiological agents of diarrhoea in hospitalized children aged less than five years in dar es salaam, tanzania.this study aimed to determine the age-specific aetiologic agents of diarrhoea in children aged less than five years. the study also assessed the efficacy of the empiric treatment of childhood diarrhoea using integrated management of childhood illness (imci) guidelines.201121345186
autophagy in immunity and cell-autonomous defense against intracellular microbes.autophagy was viewed until very recently primarily as a metabolic and intracellular biomass and organelle quality and quantity control pathway. it has now been recognized that autophagy represents a bona fide immunologic process with a wide array of roles in immunity. the immunologic functions of autophagy, as we understand them now, span both innate and adaptive immunity. they range from unique and sometimes highly specialized immunologic effectors and regulatory functions (referred to here as ...201121349088
function-specific accelerations in rates of sequence evolution suggest predictable epistatic responses to reduced effective population size.changes in effective population size impinge on patterns of molecular evolution. notably, slightly deleterious mutations are more likely to drift to fixation in smaller populations, which should typically also lead to an overall acceleration in the rates of evolution. this prediction has been validated empirically for several endosymbiont and island taxa. here, we first show that rate accelerations are also evident in bacterial pathogens whose recent shifts in virulence make them prime candidate ...201121349981
rapid emergence of third-generation cephalosporin resistance in shigella sp. isolated in andaman and nicobar islands, india.shigellosis is a major cause of diarrheal diseases among children in andaman & nicobar islands, india, which have a population of 350,000 people, including settlers from mainland india and 6 indigenous tribes. from the last one-and-half decade, we have been monitoring the species distribution and emergence of antibiotic resistance among the isolates of shigella. the circulating shigella strains have been found rapidly acquiring resistance to a wide spectrum of antibiotics. the recent data indica ...201121352076
antigen-specific cd8(+) t cells fail to respond to shigella flexneri.cd8(+) t lymphocytes often play a primary role in adaptive immunity to cytosolic microbial pathogens. surprisingly, cd8(+) t cells are not required for protective immunity to the enteric pathogen shigella flexneri, despite the ability of shigella to actively secrete proteins into the host cytoplasm, a location from which antigenic peptides are processed for presentation to cd8(+) t cells. to determine why cd8(+) t cells fail to play a role in adaptive immunity to s. flexneri, we investigated whe ...201121357720
[enterobacteriaceae infection - diagnosis, antibiotic resistance and prevention].intestinal infections caused by rod-shaped bacteria of the enterobacteriaceae genus are one of the major health hazards in countries where sanitation standards are low. strains of shigella, salmonella, escherichia and yersinia are responsible for diarrhea, severe bacillary dysentery, typhoid, other intestinal diseases, as well as genitourinary tract and blood infections. according to the who there are 4.5 billion cases every year, of which 1.9 million end in death. this makes intestinal infectio ...201121357995
whole-genome phylogeny of escherichia coli/shigella group by feature frequency profiles (ffps).a whole-genome phylogeny of the escherichia coli/shigella group was constructed by using the feature frequency profile (ffp) method. this alignment-free approach uses the frequencies of l-mer features of whole genomes to infer phylogenic distances. we present two phylogenies that accentuate different aspects of e. coli/shigella genomic evolution: (i) one based on the compositions of all possible features of length l = 24 (∼8.4 million features), which are likely to reveal the phenetic grouping a ...201121536867
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