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shigella flexneri bacteremia in adult. 201222923931
molecular profiling of antimicrobial resistance and integron association of multidrug-resistant clinical isolates of shigella species from faisalabad, pakistan.bacillary dysentery, common in developing countries, is usually caused by shigella species. a major problem in shigellosis is the rapid emergence of multidrug-resistant strains. this is the first detailed molecular study on drug resistance of shigella isolates from the faisalabad region of pakistan. ninety-five shigella isolates obtained after screening of 2500 stool samples were evaluated for in vitro resistance to commonly used antimicrobial agents; the presence or absence of 20 of the most re ...201222906205
bacterial secretion and the role of diffusive and subdiffusive first passage processes.by funneling protein effectors through needle complexes located on the cellular membrane, bacteria are able to infect host cells during type iii secretion events. the spatio-temporal mechanisms through which these events occur are however not fully understood, due in part to the inherent challenges in tracking single molecules moving within an intracellular medium. as a result, theoretical predictions of secretion times are still lacking. here we provide a model that quantifies, depending on the ...201222879888
emergence of a novel shigella flexneri serotype 1d in china.we report on the isolation of 5 shigella flexneri strains displaying a novel serotype, 1d, that shares serologic features from both s. flexneri serotypes 1a and x. the 1d strains contained serotype-converting bacteriophages sfi and sfx in tandem on the chromosome. these strains were likely originated from serotype x strains through sfi infection.201222858548
characterization of lipid a profiles from shigella flexneri variant x lipopolysaccharide.in developing countries, shigella flexneri (sf) is the major causative agent of the endemic shigellosis (bacillary dysentery) responsible annually for one million fatalities mostly among infants. lipopolysaccharides (lpss) are characteristic components of the outer membrane of the overwhelming majority of gram-negative bacteria. since lipid a is essential for the viability of the gram-negative bacteria, it is subject to extensive chemical studies with new analytical techniques.201222847700
virb-mediated positive feedback control of the virulence gene regulatory cascade of shigella flexneri.shigella flexneri is a facultative intracellular pathogen that relies on a type iii secretion system and its associated effector proteins to cause bacillary dysentery in humans. the genes that encode this virulence system are located on a 230-kbp plasmid and are transcribed in response to thermal, osmotic, and ph signals that are characteristic of the human lower gut. the virulence genes are organized within a regulatory cascade, and the nucleoid-associated protein h-ns represses each of the key ...201222821978
[analysis of etiological surveillance results of shigella spp between 2009 and 2010 in henan province].to explore the etiologic characteristics of bacillary dysentery found in henan province, between year 2009 and 2010.201222800632
[multilocus variable-number tandem-repeat analysis for molecular subtypes of shigella isolates in beijing].selecting variable-number tandem-repeat (vntr) loci for different serogroups of shigella spp to explore and establish multilocus variable-number tandem-repeat analysis (mlva) method, in order to study the molecular characteristic of the isolated strains.201222800631
identification of critical residues of the serotype modifying o-acetyltransferase of shigella flexneri.thirteen serotypes of shigella flexneri (s. flexneri) have been recognised, all of which are capable of causing bacillary dysentery or shigellosis. with the emergence of the newer s. flexneri serotypes, the development of an effective vaccine has only become more challenging. one of the factors responsible for the generation of serotype diversity is an lps o-antigen modifying, integral membrane protein known as o-acetyltransferase or oac. oac functions by adding an acetyl group to a specific o-a ...201222793174
molecular dynamics simulations of carbohydrate-mimetic haptens in complex with a complementary anti-carbohydrate antibody.the monoclonal antibody sya/j6 is specific for the o-polysaccharide of the shigella flexneri y bacterium. two haptens, a pentasaccharide and a mimetic octapeptide, bind to sya/j6 with moderate binding affinities. in a previous attempt to obtain improved binding affinity to sya/j6, two glycopeptide chimeras (α-glycopeptide and β-glycopeptide) were designed based on the structures of the pentasaccharide and the octapeptide, as well as a molecular docking study. despite the overall fit of the ligan ...201222789717
shigella flexneri bacteremia in two immune-competent adult travelers.shigella bacteremias are uncommon in immune-competent adults. we report two cases of shigella flexneri bacteremia that occurred in healthy young travelers, who recovered. self-medication with loperamide and ibuprofen without antibiotics (case 1) and concomitant falciparum malaria (case 2) were the only co-morbidities found in our two patients.201222776390
[construction of prokaryotic expression vectors for tandem affinity purification].to construct prokaryotic expression vectors suitable for tandem affinity purification to study protein-protein interactions in bacteria.201222712409
the normal chain length distribution of the o antigen is required for the interaction of shigella flexneri 2a with polarized caco-2 cells.shigella flexneri causes bacillary dysentery in humans. essential to the establishment of the disease is the invasion of the colonic epithelial cells. here we investigated the role of the lipopolysaccharide (lps) o antigen in the ability of s. flexneri to adhere to and invade polarized caco-2 cells. the s. flexneri 2a o antigen has two preferred chain lengths: a short o antigen (s-oag) regulated by the wzzb protein and a very long o antigen (vl-oag) regulated by wzz phs2. mutants with defined de ...201222688980
nlrp10 enhances shigella-induced pro-inflammatory responses.members of the nlr family evolved as intracellular sensors for bacterial and viral infection. however, our knowledge on the implication of most of the human nlr proteins in innate immune responses still remains fragmentary. here we characterized the role of human nlrp10 in bacterial infection. our data revealed that nlrp10 is a cytoplasmic localized protein that positively contributes to innate immune responses induced by the invasive bacterial pathogen shigella flexneri. sirna-mediated knock-do ...201222672233
two live attenuated shigella flexneri 2a strains wrsf2g12 and wrsf2g15: a new combination of gene deletions for 2nd generation live attenuated vaccine candidates.shigella infections are a major cause of inflammatory diarrhea and dysentery worldwide. first-generation virg-based live attenuated shigella strains have been successfully tested in phase i and ii clinical trials and are a leading approach for shigella vaccine development. additional gene deletions in sena, senb and msbb2 have been engineered into second-generation virg-based shigella flexneri 2a strains producing wrsf2g12 and wrsf2g15. both strains harbor a unique combination of gene deletions ...201222658966
roles of h2 uptake hydrogenases in shigella flexneri acid tolerance.hydrogenases play many roles in bacterial physiology, and use of h(2) by the uptake-type enzymes of animal pathogens is of particular interest. hydrogenases have never been studied in the pathogen shigella, so targeted mutant strains were individually generated in the two shigella flexneri h(2)-uptake enzymes (hya and hyb) and in the h(2)-evolving enzyme (hyc) to address their roles. under anaerobic fermentative conditions, a hya mutant strain (hya) was unable to oxidize h(2), while a hyb mutant ...201222628482
[development of a singleplex pcr assay targeting o-antigen modification genes for molecular serotyping of shigella flexneri].to develop a singleplex pcr assay targeting o-antigen modification genes for molecular serotyping of shigella (s.) flexneri.201222613389
antimicrobial susceptibility patterns of shigella isolates in foodborne diseases active surveillance network (foodnet) sites, 2000-2010.treatment of shigellosis with appropriate antimicrobial agents shortens duration of illness and bacterial shedding, but resistance to commonly used agents is increasing.201222572670
genome sequence of shigella flexneri serotype 5a strain m90t sm.bacteria of the genus shigella are a major cause of death worldwide (l. von seidlein et al., plos med. 3:e353, 2006). we sequenced the genome of shigella flexneri strain m90t sm (serotype 5a) and compared it to the published genome sequence of s. flexneri strain 8401 (serotype 5b).201222582379
shigella flexneri effectors ospe1 and ospe2 mediate induced adherence to the colonic epithelium following bile salts exposure.shigella flexneri is a gram-negative pathogen that invades the colonic epithelium. while invasion has been thoroughly investigated, it is unknown how shigella first attaches to the epithelium. previous literature suggests that shigella utilizes adhesins that are induced by environmental signals, including bile salts, encountered in the small intestine prior to invasion. we hypothesized that bile would induce adherence factors to facilitate attachment to colonic epithelial cells. to test our hypo ...201222571618
prevalence of plasmid-mediated quinolone resistance determinants in association with β-lactamases, 16s rrna methylase genes and integrons amongst clinical isolates of shigella flexneri. 201222556328
hierarchies of host factor dynamics at the entry site of shigella flexneri during host cell invasion.shigella flexneri, the causative agent of bacillary dysentery, induces massive cytoskeletal rearrangement, resulting in its entry into nonphagocytic epithelial cells. the bacterium-engulfing membrane ruffles are formed by polymerizing actin, a process activated through injected bacterial effectors that target host small gtpases and tyrosine kinases. once inside the host cell, s. flexneri escapes from the endocytic vacuole within minutes to move intra- and intercellularly. we quantified the fluor ...201222526677
self-association of the shigella flexneri icsa autotransporter protein.the icsa autotransporter protein is a major virulence factor of the human intracellular pathogen shigella flexneri. icsa is distributed at the poles in the outer membrane (om) of s. flexneri and interacts with components of the host actin-polymerization machinery to facilitate intracellular actin-based motility and subsequent cell-to-cell spreading of the bacterium. we sought to characterize the biochemical properties of icsa in the bacterial om. chemical cross-linking data suggested that icsa e ...201222516224
standardization and international multicenter validation of a pulsenet pulsed-field gel electrophoresis protocol for subtyping shigella flexneri isolates.shigella flexneri is one of the agents most frequently linked to diarrheal illness in developing countries and often causes outbreaks in settings with poor hygiene or sanitary conditions. travel is one of the means by which s. flexneri can be imported into developed countries, where this pathogen is not commonly seen. a robust and discriminatory subtyping method is needed for the surveillance of s. flexneri locally and regionally, and to aid in the detection and investigation of outbreaks. the p ...201222506731
epidemiological study of shigellosis in an urban area of argentina.shigellosis represents one of the main causes of bloody diarrhoea in south america. this study aimed to establish the incidence of shigellosis in an urban zone of buenos aires, argentina, by examining the type of shigella and living conditions associated with this infection.201222505441
ongoing outbreak of shigella flexneri serotype 3a in men who have sex with men in england and wales, data from 2009-2011.diagnoses of shigella flexneri in the united kingdom (uk) are usually travel-related. however, since 2009, there has been an overall increase in uk-acquired cases. the health protection agency has been investigating a national outbreak of s. flexneri detected in 2011 and which is still ongoing. cases occurred mostly in men who have sex with men and were of serotype 3a. the investigation aimed at obtaining epidemiological data to inform targeted outbreak management and control.201222490381
comparison of the prevalence and changing resistance to nalidixic acid and ciprofloxacin of shigella between europe-america and asia-africa from 1998 to 2009.shigella is becoming an increasing public health problem due to development of multiple antimicrobial resistance, frequently resulting in treatment failure. a systematic review was conducted based on a literature search of computerised databases. random or fixed-effects models were used, based on the p-value considering the possibility of heterogeneity between studies, for meta-analysis. statistical analyses were performed using stata 10.0. in the area of asia-africa, resistance rates to nalidix ...201222483324
ultrastructural analysis of ipad at the tip of the nascent mxih type iii secretion apparatus of shigella flexneri.shigella flexneri is a gram-negative enteric pathogen that is the predominant cause of bacillary dysentery. shigella uses a type iii secretion system to deliver effector proteins that alter normal target cell functions to promote pathogen invasion. the type iii secretion apparatus (t3sa) consists of a basal body, an extracellular needle, and a tip complex that is responsible for delivering effectors into the host cell cytoplasm. ipad [ipa (invasion plasmid antigen)] is the first protein to local ...201222480614
structural characterization of closely related o-antigen lipopolysaccharide (lps) chain length regulators.the surface o-antigen polymers of gram-negative bacteria exhibit a modal length distribution that depends on dedicated chain length regulator periplasmic proteins (polysaccharide co-polymerases, pcps) anchored in the inner membrane by two transmembrane helices. in an attempt to determine whether structural changes underlie the o-antigen modal length specification, we have determined the crystal structures of several closely related pcps, namely two chimeric pcp-1 family members solved at 1.6 and ...201222437828
characterization of the promoter, mxie box and 5' utr of genes controlled by the activity of the type iii secretion apparatus in shigella flexneri.activation of the type iii secretion apparatus (t3sa) of shigella flexneri, upon contact of the bacteria with host cells, and its deregulation, as in ipab mutants, specifically increases transcription of a set of effector-encoding genes controlled by mxie, an activator of the arac family, and ipgc, the chaperone of the ipab and ipac translocators. thirteen genes carried by the virulence plasmid (ospb, ospc1, ospd2, ospd3, ospe1, ospe2, ospf, ospg, vira, ipah1.4, ipah4.5, ipah7.8 and ipah9.8) and ...201222427898
calpain activation by the shigella flexneri effector vira regulates key steps in the formation and life of the bacterium's epithelial niche.the enteropathogen shigella flexneri invades epithelial cells, leading to inflammation and tissue destruction. we report that shigella infection of epithelial cells induces an early genotoxic stress, but the resulting p53 response and cell death are impaired due to the bacterium's ability to promote p53 degradation, mainly through calpain protease activation. calpain activation is promoted by the shigella virulence effector vira and dependent on calcium flux and the depletion of the endogenous c ...201222423964
identification of the bile salt binding site on ipad from shigella flexneri and the influence of ligand binding on ipad structure.type iii secretion (tts) is an essential virulence factor for shigella flexneri, the causative agent of shigellosis. the shigella tts apparatus (ttsa) is an elegant nanomachine that is composed of a basal body, an external needle to deliver effectors into human cells, and a needle tip complex that controls secretion activation. ipad is at the tip of the nascent ttsa needle where it controls the first step of tts activation. the bile salt deoxycholate (doc) binds to ipad to induce recruitment of ...201222423359
the shigella flexneri effector ospi deamidates ubc13 to dampen the inflammatory response.many bacterial pathogens can enter various host cells and then survive intracellularly, transiently evade humoral immunity, and further disseminate to other cells and tissues. when bacteria enter host cells and replicate intracellularly, the host cells sense the invading bacteria as damage-associated molecular patterns (damps) and pathogen-associated molecular patterns (pamps) by way of various pattern recognition receptors. as a result, the host cells induce alarm signals that activate the inna ...201222407319
structure of a type iii secretion needle at 7-å resolution provides insights into its assembly and signaling mechanisms.type iii secretion systems of gram-negative bacteria form injection devices that deliver effector proteins into eukaryotic cells during infection. they span both bacterial membranes and the extracellular space to connect with the host cell plasma membrane. their extracellular portion is a needle-like, hollow tube that serves as a secretion conduit for effector proteins. the needle of shigella flexneri is approximately 50-nm long and 7-nm thick and is made by the helical assembly of one protein, ...201222388746
enhanced type iii secretion system expression of atypical shigella flexneri ii:(3)4,7(8).we aimed at evaluating the virulence of atypical shigella flexneri ii:(3)4,7(8) by dna microarray and invasion assay.201224159518
cephalosporin-resistant shigella flexneri over 9 years (2001-09) in india.to determine the pattern and antimicrobial resistance genes of cephalosporin resistance in shigella flexneri and shigella dysenteriae over 9 years.201222410619
studies on shigella boydii infection in caenorhabditis elegans and bioinformatics analysis of immune regulatory protein interactions.shigella boydii causes bacillary dysentery or shigellosis and generates a significant burden in the developing nations. s. boydii-mediated infection assays were performed at both physiological and molecular levels using caenorhabditis elegans as a host. continuous exposure of worms to s. boydii showed a reduced life span indicating the pathogenicity of shigella. quantitative real-time pcr analysis was performed to analyze the expression and regulation of host specific candidate-antimicrobial gen ...201222841995
outer membrane vesicles of shigella boydii type 4 induce passive immunity in neonatal mice.like most other gram-negative bacteria, shigella releases outer membrane vesicles (omvs) into the surrounding environment during growth. in this study, we have exploited omvs of shigella as a protective immunogen in a mice model against shigellosis. distinctive vesicle secretion was noticed from different shigella strains. among them, shigella boydii type 4 (bch612) was secreting relatively higher amounts. we immunized female adult mice orally with 32 μg of purified shigella boydii type 4 (bch61 ...201222762732
effect of bovine lactoferrin on the minimum inhibitory concentrations of ampicillin and trimethoprim-sulfamethoxazole for clinical shigella spp. strains.here, we determined the effect of bovine lactoferrin (blf) on the minimum inhibitory concentration (mic) of ampicillin and trimethoprim-sulfamethoxazole in shigella . using a microdilution method, the mic was determined in the presence or absence of bovine lactoferrin (10 mg/ml) on 88 shigella strains (56 shigella flexneri , 15 shigella boydii , 13 shigella sonnei , and 4 shigella dysenteriae ) previously isolated from peruvian children <2 years old. a fold change of 2 or more in mic values was ...201222397495
antimicrobial-resistant shigella infections from iran: an overlooked problem?in this study, we wanted to assess the level of antimicrobial resistance, the presence of genes encoding resistance to cephalosporins and plasmid-mediated quinolone resistance (pmqr), and genetic relatedness among shigella isolates obtained from iranian patients.201222345385
bacterial virulence proteins as tools to rewire kinase pathways in yeast and immune cells.bacterial pathogens have evolved specific effector proteins that, by interfacing with host kinase signalling pathways, provide a mechanism to evade immune responses during infection. although these effectors contribute to pathogen virulence, we realized that they might also serve as valuable synthetic biology reagents for engineering cellular behaviour. here we exploit two effector proteins, the shigella flexneri ospf protein and yersinia pestis yoph protein, to rewire kinase-mediated responses ...201222820255
complete nucleotide sequence of pvqs1 containing a quinolone resistance determinant from salmonella enterica serovar virchow associated with foreign travel.nalidixic acid-resistant salmonella enterica serovars kentucky (n = 5) and virchow (n = 6) cultured from individuals were investigated for the presence of plasmid-mediated quinolone resistance (pmqr) determinants.201222553140
[antagonistic activity of lactobacilli of the colon].study of antagonistic activity of lactobacilli of the colon against members of its autochthonous bacterial flora and agents of some acute infectious and chronic diseases of the gastrointestinal tract.201222442970
effect of x-ray treatments on pathogenic bacteria, inherent microbiota, color, and texture on parsley leaves.this work is a part of systematic studies of the effect of x-ray treatments on fresh produce. the main objective of this investigation was to study the effects of x-ray treatments in reducing the concentration of artificially inoculated escherichia coli o157:h7, listeria monocytogenes, salmonella enterica, and shigella flexneri, and inherent microbiota on parsley leaves. the secondary objective was to study the effects of x-ray treatments on color and texture parameters on treated parsley leaves ...201223035726
effects of x-ray treatments on pathogenic bacteria, inherent microflora, color, and firmness on whole cantaloupe.inactivation of inoculated escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri on whole cantaloupes using x-ray at different doses (0.1, 0.5, 1.0, 1.5, and 2.0 kgy) was studied. the effect of x-ray on quality parameters (color and texture) of untreated and treated whole cantaloupes was instrumentally determined. the effect of x-ray on microflora counts (mesophilic counts, psychrotrophic counts and yeast and mold counts) of untreated and treated whole canta ...201222560020
shigella flexneri utilize the spectrin cytoskeleton during invasion and comet tail generation.the spectrin cytoskeleton is emerging as an important host cell target of enteric bacterial pathogens. recent studies have identified a crucial role for spectrin and its associated proteins during key pathogenic processes of listeria monocytogenes and salmonella typhimurium infections. here we investigate the involvement of spectrin cytoskeletal components during the pathogenesis of the invasive pathogen shigella flexneri.201222424399
development and evaluation of a multiplex pcr for simultaneous detection of five foodborne pathogens.to develop a rapid multiplex pcr method for simultaneous detection of five major foodborne pathogens (staphylococcus aureus, listeria monocytogenes, escherichia coli o157:h7, salmonella enteritidis and shigella flexneri, respectively).201222268759
pa2800 plays an important role in both antibiotic susceptibility and virulence in pseudomonas aeruginosa.pseudomonas aeruginosa is an important human pathogen which causes a variety of infections. p. aeruginosa infections are often difficult to treat due to the pathogen's resistance to many antibiotics. previously, it has been reported that a transposon insertion mutant in gene pa2800 of p. aeruginosa pao1 was more sensitive to tetracycline and ciprofloxacin. further characterization of this gene, a vacj homolog, in this study indicated that this gene plays an important role in both antibiotic susc ...201222878555
shigella sonnei genome sequencing and phylogenetic analysis indicate recent global dissemination from europe.shigella are human-adapted escherichia coli that have gained the ability to invade the human gut mucosa and cause dysentery(1,2), spreading efficiently via low-dose fecal-oral transmission(3,4). historically, s. sonnei has been predominantly responsible for dysentery in developed countries but is now emerging as a problem in the developing world, seeming to replace the more diverse shigella flexneri in areas undergoing economic development and improvements in water quality(4-6). classical approa ...201222863732
from lin-benzoguanines to lin-benzohypoxanthines as ligands for zymomonas mobilis trna-guanine transglycosylase: replacement of protein-ligand hydrogen bonding by importing water clusters.the foodborne illness shigellosis is caused by shigella bacteria that secrete the highly cytotoxic shiga toxin, which is also formed by the closely related enterohemorrhagic escherichia coli (ehec). it has been shown that trna-guanine transglycosylase (tgt) is essential for the pathogenicity of shigella flexneri. herein, the molecular recognition properties of a guanine binding pocket in zymomonas mobilis tgt are investigated with a series of lin-benzohypoxanthine- and lin-benzoguanine-based inh ...201222736391
role of anionic charges of periplasmic glucans of shigella flexneri in overcoming detergent stress.osmoregulated periplasmic glucans (opgs) are synthesized by the members of the family enterobacteriaceae when grown under low osmotic growth conditions. enteropathogens such as shigella flexneri spend considerable time outside the host environment such as irrigation waters where low nutrient low osmolarity conditions normally may exist. we recently demonstrated that opgs of s. flexneri are required for optimal growth under low osmolarity low nutrient conditions. based on homology of the opg bios ...201222730962
shigella flexneri o-antigens revisited: final elucidation of the o-acetylation profiles and a survey of the o-antigen structure diversity.shigella flexneri is an important human pathogen causing shigellosis. strains of s. flexneri are serologically heterogeneous and, based on o-antigens, are currently classified into 14 types. structures of the o-antigens (o-polysaccharides) of s. flexneri have been under study since 1960s but some gaps still remained. in this work, using one- and two-dimensional (1) h- and (13) c-nmr spectroscopy, the o-polysaccharides of several s. flexneri types were reinvestigated, and their structures were ei ...201222724405
antimicrobial activity of sesbania grandiflora flower polyphenol extracts on some pathogenic bacteria and growth stimulatory effect on the probiotic organism lactobacillus acidophilus.polyphenolic extracts (pe) of edible flower of sesbania grandiflora were tested to evaluate its antimicrobial effect against some common pathogenic bacteria and growth promoting property against probiotic organism lactobacillus acidophilus. the antimicrobial activity of s. grandiflora flower pe against selected pathogens was evaluated using both in vitro and in situ methods. in vitro studies suggested that pe has inhibitory effect against staphylococcus aureus, shigella flexneri 2a, salmonella t ...201222583547
conversion of viable but nonculturable enteric bacteria to culturable by co-culture with eukaryotic cells.viable but nonculturable (vbnc) vibrio cholerae non-o1/non-o139, v. parahaemolyticus, enterohemorrhagic escherichia coli, enterotoxigenic e. coli, enteropathogenic e. coli, shigella flexneri, and salmonella enterica were converted to the culturable state by co-culture with selected eukaryotic cells, e.g., ht-29, caco-2, t84, hela, intestine 407, and cho cells.201222537150
molecular-phylogenetic characterization of the microbiota in ulcerated and non-ulcerated regions in the patients with crohn's disease.the dysbiosis of intestinal microbiota has been established in crohn's disease (cd), but the molecular characterization of this dysbiosis in chinese subjects with cd remains unclear. this study aims to investigate the predominant bacterial composition of the faecal and mucosal-associated microbiota in chinese cd patients using culture-independent techniques.201222529960
binding affects the tertiary and quaternary structures of the shigella translocator protein ipab and its chaperone ipgc.shigella flexneri uses its type iii secretion system (t3ss) to promote invasion of human intestinal epithelial cells as the first step in causing shigellosis, a life-threatening form of dysentery. the shigella type iii secretion apparatus (t3sa) consists of a basal body that spans the bacterial envelope and an exposed needle that injects effector proteins into target cells. the nascent shigella t3sa needle is topped with a pentamer of the needle tip protein invasion plasmid antigen d (ipad). bil ...201222497344
ethnopharmacological study of plants from pondoland used against diarrhoea.waterborne diseases such as diarrhoea are common world wide, including in bizana, south africa where the majority of rural dwellers depend largely on water from unprotected sources. the people from bizana use medicinal plants as their first line of health care to cure and prevent diarrhoea.201222338648
recognition of enteroinvasive escherichia coli and shigella flexneri by dendritic cells: distinct dendritic cell activation states.the innate and adaptive immune responses of dendritic cells (dcs) to enteroinvasive escherichia coli (eiec) infection were compared with dc responses to shigella flexneri infection. eiec triggered dcs to produce interleukin (il)-10, il-12 and tumour necrosis factor (tnf)-α, whereas s. flexneri induced only the production of tnf-α. unlike s. flexneri, eiec strongly increased the expression of toll like receptor (tlr)-4 and tlr-5 in dcs and diminished the expression of co-stimulatory molecules tha ...201222310548
icsa autotransporter passenger promotes increased fusion protein expression on the cell surface.autotransporters are attractive cell surface display vehicles as they lack complex adaptor proteins necessary for protein export. recent reports have suggested that the native effector domain (α domain) and translocation domain (β domain) interact with each other to drive translocation of the effector domain to the outer membrane. in this report we compared the expression, surface localisation and folding of tem-1 β-lactamase (bla) and maltose binding protein (male or mbp) fused to either full l ...201222309506
glutamate decarboxylase-dependent acid resistance in orally acquired bacteria: function, distribution and biomedical implications of the gadbc operon.for successful colonization of the mammalian host, orally acquired bacteria must overcome the extreme acidic stress (ph < 2.5) encountered during transit through the host stomach. the glutamate-dependent acid resistance (gdar) system is by far the most potent acid resistance system in commensal and pathogenic escherichia coli, shigella flexneri, listeria monocytogenes and lactococcus lactis. gdar requires the activity of glutamate decarboxylase (gadb), an intracellular plp-dependent enzyme which ...201222995042
microbiota, innate immune system, and gastrointestinal muscle: ongoing studies.to test the activities of culture-extracted or commercially available toll-like receptors (tlrs) ligands to establish their direct impact on target gastrointestinal motor cells.201222955360
structurally distinct bacterial tbc-like gaps link arf gtpase to rab1 inactivation to counteract host defenses.rab gtpases are frequent targets of vacuole-living bacterial pathogens for appropriate trafficking of the vacuole. here we discover that bacterial effectors including vira from nonvacuole shigella flexneri and espg from extracellular enteropathogenic escherichia coli (epec) harbor tbc-like dual-finger motifs and exhibits potent rabgap activities. specific inactivation of rab1 by vira/espg disrupts er-to-golgi trafficking. s. flexneri intracellular persistence requires vira tbc-like gap activity ...201222939626
differential modulation of intracellular survival of cytosolic and vacuolar pathogens by curcumin.curcumin, a principal component of turmeric, acts as an immunomodulator regulating the host defenses in response to a diseased condition. the role of curcumin in controlling certain infectious diseases is highly controversial. it is known to alleviate symptoms of helicobacter pylori infection and exacerbate that of leishmania infection. we have evaluated the role of curcumin in modulating the fate of various intracellular bacterial pathogens. we show that pretreatment of macrophages with curcumi ...201222890770
systemic shigellosis in south africa.systemic disease due to shigellae is associated with human immunodeficiency virus (hiv), malnutrition, and other immunosuppressed states. we examined the clinical and microbiologic characteristics of systemic shigellosis in south africa, where rates of hiv infection are high.201222474223
intestinal microbial community diversity between healthy and orally infected rabbit with entamoeba histolytica by eric-pcr.enterobacterial repetitive intergenic consensus (eric)-pcr was applied to analyze the difference of intestinal microbial community diversity between healthy and orally infected rabbits with entamoeba histolytica. the dynamic changes in different parts of digestive system including the duodenum, jejunum, ileum, caecum, and rectum in healthy and infected rabbits at different time points were also tested. the intestinal microbial community of the control healthy rabbits was steady, and the total nu ...201222562215
in vitro antimicrobial activity on clinical microbial strains and antioxidant properties of artemisia parviflora.artemisia parviflora leaf extracts were evaluated for potential antimicrobial and antioxidant properties. antimicrobial susceptibility assay was performed against ten standard reference bacterial strains. antioxidant activity was analyzed using the ferric thiocyanate and 2, 2-diphenyl-1-picrylhydrazyl (dpph) assays. radical scavenging activity and total phenolic content were compared. phytochemical analyses were performed to identify the major bioactive constitution of the plant extract.201223171441
outer membrane protein a (ompa): a new player in shigella flexneri protrusion formation and inter-cellular spreading.outer membrane protein a (ompa) is a multifaceted predominant outer membrane protein of escherichia coli and other enterobacteriaceae whose role in the pathogenesis of various bacterial infections has recently been recognized. here, the role of ompa on the virulence of shigella flexneri has been investigated. an ompa mutant of wild-type s. flexneri 5a strain m90t was constructed (strain hnd92) and it was shown to be severely impaired in cell-to-cell spreading since it failed to plaque on hela ce ...201223166731
activation of type iii interferon genes by pathogenic bacteria in infected epithelial cells and mouse placenta.bacterial infections trigger the expression of type i and ii interferon genes but little is known about their effect on type iii interferon (ifn-λ) genes, whose products play important roles in epithelial innate immunity against viruses. here, we studied the expression of ifn-λ genes in cultured human epithelial cells infected with different pathogenic bacteria and in the mouse placenta infected with listeria monocytogenes. we first showed that in intestinal lovo cells, induction of ifn-λ genes ...201222720036
metal based new triazoles: their synthesis, characterization and antibacterial/antifungal activities.a series of new triazoles and their oxovanadium(iv) complexes have been synthesized, characterized and evaluated for antibacterial/antifungal properties. the new schiff bases ligands (l(1))-(l(5)) were prepared by the condensation reaction of 3,5-diamino-1,2,4-triazole with 2-hydroxy-1-naphthaldehyde, pyrrole-2-carboxaldehyde, pyridine-2-carboxaldehyde, 2-acetyl pyridine and 2-methoxy benzaldehyde. the structures of the ligands have been established on the basis of their physical, spectral (ir, ...201222982389
antibacterial, antifungal and antioxidant activities of the ethanol extract of the stem bark of clausena heptaphylla.there is wide spread interest in drugs derived from plants as green medicine is believed to be safe and dependable, compared with costly synthetic drugs that have adverse effects.201223181593
investigations of antimicrobial activity of some cameroonian medicinal plant extracts against bacteria and yeast with gastrointestinal relevance.resistance against antibiotics of many bacteria is accumulating. therefore, searches for new substances with antimicrobial activity have become an urgent necessity. medicinal plants are frequently used in popular medicine as remedies for many infectious diseases (intestinal infection, malaria, tuberculosis, etc.).201222583961
milk microbiome signatures of subclinical mastitis-affected cattle analysed by shotgun sequencing.metagenomic analysis of milk samples collected from kankrej, gir (bos indicus) and crossbred (bos taurus × b. indicus) cattle harbouring subclinical mastitis was carried out by next-generation sequencing 454 gs-flx technology to elucidate the microbial community structure of cattle milk.201222277077
synthesis of s-triazine-based thiazolidinones as antimicrobial agents.a novel series of thiazolidinone derivatives, namely 4-{4-dimethylamino-6-[4-oxo-2-phenyl-5-(4-pyridin-2-yl-piperazin-1-ylmethyl)-thiazolidin-3-yl]-[1,3,5]-triazin-2-yloxy}-1-methyl-1h-quinolin-2-ones, have been synthesized from the key intermediate 4-(4-amino-6-dimethylamino-[1,3,5]-triazin-2-yloxy)-1-methyl-1h-quinolin-2-one (5). compound 5 was condensed with various aldehydes to give schiff base derivatives, which after cyclization gave thiazolidinones that were linked with 1-pyridin-2-yl-pip ...201222624326
synthesis of benzimidazolyl-1,3,4-oxadiazol-2ylthio-n-phenyl (benzothiazolyl) acetamides as antibacterial, antifungal and antituberculosis agents.to affiliate multiple bioactivities in a compact heteronuclei, two series of benzimidazole based 1,3,4-oxadiazoles were synthesized and assessed in vitro for their efficacy as antimicrobial agents against eight bacteria (staphylococcus aureus, bacillus cereus, escherichia coli, pseudomonas aeruginosa, klebsiella pneumoniae, salmonella typhi, proteus vulgaris, shigella flexneri), four fungi (aspergillus niger, aspergillus fumigatus, aspergillus clavatus, candida albicans) and mycobacterium tuberc ...201222516426
lessons from anaplasma phagocytophilum: chromatin remodeling by bacterial effectors.bacterial pathogens can alter global host gene expression via histone modifications and chromatin remodeling in order to subvert host responses, including those involved with innate immunity, allowing for bacterial survival. shigella flexneri, listeria monocytogenes, chlamydia trachomatis, and anaplasma phagocytophilum express effector proteins that modify host histones and chromatin structure. a. phagocytophilum modulates granulocyte respiratory burst in part by dampening transcription of sever ...201223082961
molecular cloning and characterization of nucleotide binding and oligomerization domain-1 (nod1) receptor in the indian major carp, rohu (labeo rohita), and analysis of its inductive expression and down-stream signalling molecules following ligands exposure and gram-negative bacterial infections.nucleotide binding and oligomerization domain-1 (nod1) is a cytoplasmic pattern recognition receptor (prr), and is a member of the nod-like receptor (nlr) family. it senses a wide range of bacteria and viruses or their products, and plays a key role in inducing innate immunity. in this report, nod1 gene was cloned and characterized in rohu (labeo rohita), a fish species of highest commercial importance in the indian subcontinent. the full-length rohu nod1 (rnod1) cdna comprised of 3168 bp with a ...201222530240
emergence and stability of high-pressure resistance in different food-borne pathogens.high hydrostatic pressure (hhp) processing is becoming a valuable nonthermal food pasteurization technique, although there is reasonable concern that bacterial hhp resistance could compromise the safety and stability of hhp-processed foods. while the degree of natural hhp resistance has already been shown to vary greatly among and within bacterial species, a still unresolved question remains as to what extent different food-borne pathogens can actually develop hhp resistance. in this study, we t ...201222344661
high load of multi-drug resistant nosocomial neonatal pathogens carried by cockroaches in a neonatal intensive care unit at tikur anbessa specialized hospital, addis ababa, ethiopia. 201222958880
expression of shigella flexneri gluq-rs gene is linked to dksa and controlled by a transcriptional terminator.glutamyl queuosine-trna(asp) synthetase (gluq-rs) is a paralog of the catalytic domain of glutamyl-trna synthetase and catalyzes the formation of glutamyl-queuosine on the wobble position of trna(asp). here we analyze the transcription of its gene in shigella flexneri, where it is found downstream of dksa, which encodes a transcriptional regulator involved in stress responses.201223035718
expanding the use of a fluorogenic method to determine activity and mode of action of bacillus thuringiensis bacteriocins against gram-positive and gram-negative bacteria.previously we described a rapid fluorogenic method to measure the activity of five bacteriocins produced by mexican strains of bacillus thuringiensis against b. cereus 183. here we standardize this method to efficiently determine the activity of bacteriocins against both gram-positive and gram-negative bacteria. it was determined that the crucial parameter required to obtain reproducible results was the number of cells used in the assay, that is, ~4 × 10(8) cell/ml and ~7 × 10(8) cell/ml, respec ...201222919330
origin of dreams: anticipation of modern theories in the philosophy and physiology of the eighteenth and nineteenth centuries. 20123532158
chaperones during genital examinations: theory to practice. 20123578176
chaperones during genital examinations: theory to practice. 20123578176
strictures of the bile ducts. 20124180267
strictures of the bile ducts. 20124180267
[advances in the diagnosis and treatment of pulmonary embolism]. 20123601774
[rubinstein-taybi syndrome with multiple keloids].the authors report an unusual case of rubinstein-taybi syndrome, in which alterations such as blepharoptosis, unilateral microphthalmia, bilateral and inferior iris, lens, and choroidal colobomas and unilateral optic nerve pit are present in addition to apparently spontaneous multiple keloids. a histopathological study of the skin and a culture of fibroblasts have pointed out a reduction of the cell duplication time.20123571836
[controlled clinical trials]. 20123561576
[controlled clinical trials]. 20123561576
dysrhythmias after direct-current cardioversion.the success rate of direct-current (dc) countershocks and postshock arrhythmias are of concern for the design of automatic devices. results of 112 dc shocks for induced ventricular tachycardia/fibrillation (vt/vf) (n = 99) or atrial fibrillation (af) were analyzed. clinical and arrhythmia characteristics were related to the success rate of dc shocks as well as postshock arrhythmias. sixty-one patients were men and 14 were women; mean age was 52 +/- 15 years. coronary artery disease was present i ...20123510522
effects on hearing during prolonged oral contraceptive use.different hearing defects have been attributed to prolonged use of oral contraceptives. the aim of the present investigation has been the evaluation by means of a number of audiological tests and of brain-stem evoked responses (bser) of the possible incidence of subclinical pathology of the nervous hearing structures in these subjects. twenty healthy subjects taking oral contraceptives from 9 to 30 months and 10 paired controls have been studied. no hearing loss was found but the study of bser s ...20123568658
effect of female odour on male hamsters mediated by the vomeronasal organ.a comparison was made of the response to female vaginal odour, between males that were intact (i), had an ablated vomeronasal epithelium (vnox) or had the main olfactory epithelium destroyed by zinc sulphate lavage (zn). i males, after exposure to vaginal odour, can subsequently discriminate between the donor of the odour and other, mismatching females. vnox males are unable to discriminate. peripherally anosmic males (zn) could still discriminate mismatching females. neither treatment affected ...20124070382
effect of female odour on male hamsters mediated by the vomeronasal organ.a comparison was made of the response to female vaginal odour, between males that were intact (i), had an ablated vomeronasal epithelium (vnox) or had the main olfactory epithelium destroyed by zinc sulphate lavage (zn). i males, after exposure to vaginal odour, can subsequently discriminate between the donor of the odour and other, mismatching females. vnox males are unable to discriminate. peripherally anosmic males (zn) could still discriminate mismatching females. neither treatment affected ...20124070382
childhood primary cutaneous non-t/non-b lymphoma followed by acute t-cell leukemia.an 8-year-old girl presented with cutaneous lymphoma without bone marrow or visceral involvement. the tumor cells displayed convoluted and invaginated euchromatic nuclei. the immunophenotype of these cells was non-t/non-b (ia+, calla-, sig-, tdt-, e-, thy-). the skin lesions regressed promptly with chemotherapy including cyclophosphamide, vincristine, methotrexate, doxorubicin, and cytosine arabinoside. six months after the completion of chemotherapy (18 months postdiagnosis), the patient had a ...20123486034
puva for cutaneous t-cell lymphoma. 10 years after. 20123485032
[observation on the subject of domestic parasites]. 20123504141
extended modified postauricular incision of the temporomandibular joint.the traditional postauricular approach to the temporomandibular joint has excellent cosmetic results since the entire incision is concealed in the postauricular flexure. excellent posterior joint exposure, good lateral joint exposure, and fair anterior joint exposure are obtained. the risk of injury to the facial nerve is decreased. an extended modification of the postauricular incision was developed to overcome some of the disadvantages of the postauricular incision while maintaining its advant ...20123468462
[tumors of the bladder and peroperative genitourinary ultrasonography. a proposal for echographic classification]. 20123524151
[hypertension in children]. 20124893774
airway smooth muscle and disease workshop. october 24-26, 1986, rotherwick, hants., u.k. proceedings. 20123662247
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