Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| development of a sandwich elisa for ehec o157:h7 intimin γ1. | enterohemorrhagic escherichia coli (ehec) o157:h7 is a zoonotic pathogen of worldwide importance that causes foodborne infections in humans. intimin gamma 1 (intimin γ1) is one of the most important outer membrane proteins required for ehec's intimate adhesion to epithelial cells. here, we generated a polyclonal antibody (pab) and a monoclonal antibody (mab) against intimin γ1 to develop a double antibody sandwich elisa (das-elisa) with increased sensitivity and specificity for measuring ehec o1 ... | 2016 | 27603508 |
| combining shigella tn-seq data with gold-standard e. coli gene deletion data suggests rare transitions between essential and non-essential gene functionality. | gene essentiality - whether or not a gene is necessary for cell growth - is a fundamental component of gene function. it is not well established how quickly gene essentiality can change, as few studies have compared empirical measures of essentiality between closely related organisms. | 2016 | 27599549 |
| supercharging reagent for enhanced liquid chromatographic separation and charging of sialylated and high-molecular-weight glycopeptides for nanohplc-esi-ms/ms analysis. | recent developments in proteomic techniques have led to the development of mass spectrometry (ms)-based methods to characterize site-specific glycosylation of proteins. however, appropriate analytical tools to characterize acidic and high-molecular-weight (hmw) glycopeptides are still lacking. in this study, we demonstrate that the addition of supercharging reagent, m-nitrobenzyl alcohol (m-nba), into mobile phases greatly facilitates the analysis of acidic and hmw glycopeptides. using commercia ... | 2016 | 27487254 |
| characterization of a biofilm-forming shigella flexneri phenotype due to deficiency in hep biosynthesis. | deficiency in biosynthesis of inner core of lipopolysaccharide (lps) rendered a characteristic biofilm-forming phenotype in e. coli. the pathological implications of this new phenotype in shigella flexneri, a highly contagious enteric gram-negative bacteria that is closely related to e. coli, were investigated in this study. the δrfac (also referred as waac) mutant, with incomplete inner core of lps due to deficiency in hep biosynthesis, was characteristic of strong biofilm formation ability and ... | 2016 | 27478696 |
| identification of a distinct substrate-binding domain in the bacterial cysteine methyltransferase effectors nlee and ospz. | the type iii secretion system effector protein nlee from enteropathogenic escherichia coli plays a key role in the inhibition of nf-κb activation during infection. nlee inactivates the ubiquitin chain binding activity of host proteins tak1-binding proteins 2 and 3 (tab2 and tab3) by modifying the npl4 zinc finger domain through s-adenosyl methionine-dependent cysteine methylation. using yeast two-hybrid protein interaction studies, we found that a conserved region between amino acids 34 and 52 o ... | 2016 | 27445336 |
| tetracycline-loaded calcium phosphate nanoparticle (tet-cpnp): rejuvenation of an obsolete antibiotic to further action. | increasing resistance in bacteria towards antibiotics has made it imperative to research on their revitalization to combat infectious diseases. this study dealt with synthesis of a nano-form of the antibiotic tetracycline, its characterization and potency of killing different multi-drug resistant diarrhea-causing bacteria. | 2016 | 27288585 |
| shigella diversity and changing landscape: insights for the twenty-first century. | shigella is a pathovar of escherichia coli comprising four groups, shigella flexneri, shigella sonnei, shigella dysenteriae, and shigella boydii, each of them, with the exception of s.sonnei, comprising several serotypes. shigella accounts for the majority of dysentery causing infections occurring world-wide each year. recent advancements in the shigella field have led to a better understanding of the molecular mechanisms underlying host epithelial cell invasion and immune cell function manipula ... | 2016 | 27148494 |
| implications of spatiotemporal regulation of shigella flexneri type three secretion activity on effector functions: think globally, act locally. | shigella spp. are gram-negative bacterial pathogens that infect human colonic epithelia and cause bacterial dysentery. these bacteria express multiple copies of a syringe-like protein complex, the type three secretion apparatus (t3sa), which is instrumental in the etiology of the disease. the t3sa triggers the plasma membrane (pm) engulfment of the bacteria by host cells during the initial entry process. it then enables bacteria to escape the resulting phagocytic-like vacuole. freed bacteria for ... | 2016 | 27014638 |
| the serine protease pic as a virulence factor of atypical enteropathogenic escherichia coli. | autotransporter proteins (at) are associated with bacterial virulence attributes. originally identified in enteroaggregative escherichia coli (eaec), shigella flexneri 2a and uropathogenic e. coli, the serine protease pic is one of these at. we have previously detected one atypical enteropathogenic e. coli strain (ba589) carrying the pic gene. in the present study, we characterized the biological activities of pic produced by ba589 both in vitro and in vivo. contrarily to other pic-producers bac ... | 2016 | 26963626 |
| establishment and application of a visual dna microarray for the detection of food-borne pathogens. | the accurate detection and identification of food-borne pathogenic microorganisms is critical for food safety nowadays. in the present work, a visual dna microarray was established and applied to detect pathogens commonly found in food, including salmonella enterica, shigella flexneri, e. coli o157:h7 and listeria monocytogenes in food samples. multiplex pcr (mpcr) was employed to simultaneously amplify specific gene fragments, fimy for salmonella, ipah for shigella, iap for l. monocytogenes and ... | 2016 | 26860568 |
| characterization of slya in shigella flexneri identifies a novel role in virulence. | the slya transcriptional regulator has important roles in the virulence and pathogenesis of several members of the enterobacteriaceae family, including salmonella enterica serovar typhimurium and escherichia coli. despite the identification of the slya gene in shigella flexneri nearly 2 decades ago, as well as the significant conservation of slya among enteric bacteria, the role of slya in shigella remains unknown. the genes regulated by slya in closely related organisms often are absent from or ... | 2016 | 26831468 |
| resin glycosides from ipomoea wolcottiana as modulators of the multidrug resistance phenotype in vitro. | recycling liquid chromatography was used for the isolation and purification of resin glycosides from the chcl3-soluble extracts prepared using flowers of ipomoea wolcottiana rose var. wolcottiana. bioassay-guided fractionation, using modulation of both antibiotic activity against multidrug-resistant strains of gram-negative bacteria and vinblastine susceptibility in breast carcinoma cells, was used to isolate the active glycolipids as modulators of the multidrug resistance phenotype. an ester-ty ... | 2016 | 26774597 |
| multi-parameter flow cytometry as a process analytical technology (pat) approach for the assessment of bacterial ghost production. | flow cytometry (fcm) is a tool for the analysis of single-cell properties in a cell suspension. in this contribution, we present an improved fcm method for the assessment of e-lysis in enterobacteriaceae. the result of the e-lysis process is empty bacterial envelopes-called bacterial ghosts (bgs)-that constitute potential products in the pharmaceutical field. bgs have reduced light scattering properties when compared with intact cells. in combination with viability information obtained from stai ... | 2016 | 26521248 |
| complete sequences and characterization of two novel plasmids carrying aac(6')-ib-cr and qnrs gene in shigella flexneri. | the complete sequences of two previously reported plasmids carrying plasmid-mediated quinolone resistance genes from shigella flexneri in china have not been available. the present study using the p5-c3 assembly method revealed that (1) the plasmid psf07201 with aac(6')-ib-cr had 75,335 bp with antibiotic resistance genes ctx-m-3, tem-1, and fosa3; (2) seven fragments of psf07201 had more than 99% homology with the seven corresponding plasmids; (3) the other plasmid psf07202 with qnrs had 47,669 ... | 2016 | 26469217 |
| manipulation of host membranes by the bacterial pathogens listeria, francisella, shigella and yersinia. | bacterial pathogens display an impressive arsenal of molecular mechanisms that allow survival in diverse host niches. subversion of plasma membrane and cytoskeletal functions are common themes associated to infection by both extracellular and intracellular pathogens. moreover, intracellular pathogens modify the structure/stability of their membrane-bound compartments and escape degradation from phagocytic or autophagic pathways. here, we review the manipulation of host membranes by listeria mono ... | 2016 | 27448494 |
| at the crossroads: communication of bacteria-containing vacuoles with host organelles. | invasive bacterial pathogens are engulfed upon host cell entry in a vacuolar environment called the bacteria-containing vacuole (bcv). bcvs directly contact with numerous host compartments, mainly vesicles of the endocytic pathway, such as endosomes or lysosomes. in addition, they also interact with the endoplasmic reticulum and endomembranes of the secretory pathway. these connections between the pathogen and the host occur either through heterotypic membrane fusions or through membrane contact ... | 2016 | 26762760 |
| failure of syndrome-based diarrhea management guidelines to detect shigella infections in kenyan children. | shigella is a leading cause of childhood diarrhea mortality in sub-saharan africa. current world health organization guidelines recommend antibiotics for children in non cholera-endemic areas only in the presence of dysentery, a proxy for suspected shigella infection. | 2016 | 26407270 |
| biological potency and characterization of antibacterial substances produced by lactobacillus pentosus isolated from hentak, a fermented fish product of north-east india. | lactic acid bacteria (lab) isolated from various foods are important due to their potential to inhibit microorganisms, including drug-resistant bacteria. the objectives of this investigation were to isolate and identify antibacterial substances producing lab from hentak, a traditional fermented fish product of manipur (north-east india), and to optimize the production of antagonistic substances present in cell free neutralized supernatant (cfns) against enteric bacterial pathogens using the 'one ... | 2016 | 27795886 |
| toxicity mechanism of titanium dioxide and zinc oxide nanoparticles against food pathogens. | food preservation is an important field of research. it extends the shelf life of major food products. our current study is based on food preservation through tio2 and zno nanoparticles. tio2 and zno are biocompatible nanomaterial. the biocompatibility of the materials were established through toxicity studies on cell lines. titanium dioxide and zinc oxide nanoparticle were synthesized by wet chemical process. they are characterized by x-ray diffraction and tem. the antibacterial activities of b ... | 2016 | 27694049 |
| structural and functional characterization of the lps transporter lptde from gram-negative pathogens. | incorporation of lipopolysaccharide (lps) into the outer membrane of gram-negative bacteria is essential for viability, and is accomplished by a two-protein complex called lptde. we solved crystal structures of the core lptde complexes from yersinia pestis, klebsiella pneumoniae, pseudomonas aeruginosa, and a full-length structure of the k. pneumoniae lptde complex. our structures adopt the same plug and 26-strand β-barrel architecture found recently for the shigella flexneri and salmonella typh ... | 2016 | 27161977 |
| kefir-isolated bacteria and yeasts inhibit shigella flexneri invasion and modulate pro-inflammatory response on intestinal epithelial cells. | the aim of this work was to evaluate the ability of a kefir-isolated microbial mixture containing three bacterial and two yeast strains (mm) to protect intestinal epithelial cells against shigella flexneri invasion, as well as to analyse the effect on pro-inflammatory response elicited by this pathogen. a significant decrease in s. flexneri strain 72 invasion was observed on both ht-29 and caco-2 cells pre-incubated with mm. pre-incubation with the individual strains saccharomyces cerevisiae cid ... | 2016 | 26503738 |
| effect of x-ray treatments on escherichia coli o157:h7, listeria monocytogenes, shigella flexneri, salmonella enterica and inherent microbiota on whole mangoes. | the aims of this investigation were to; (i) study the effect of x-ray treatments in reducing escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri on whole mangoes, and (ii) study the effect of x-ray treatments on microflora counts (mesophilic counts, psychrotrophic counts and yeast and mould counts) of whole mangoes during storage at ambient temperature (22°c) for 30 days. a mixture of three strains of each test organism was spot inoculated (100 μl; approx. ... | 2016 | 26518738 |
| the development of methods for the detection of salmonella in chickens by a combination of immunomagnetic separation and pcrs. | micro- and nanoimmunomagnetic beads (mimbs and nimbs) used for immunomagnetic separation (ims) with pcr were studied for the rapid detection of salmonella. the capture efficiency of the two different imbs was evaluated by a conventional plate counting method, and the binding pattern was studied using scanning electron microscopy. the specificity of the imbs was tested with salmonella, shigella flexneri, enterohemorrhagic escherichia coli o157:h7, and listeria monocytogenes. by comparing the pre- ... | 2016 | 27730684 |
| intestinal organoids as a novel tool to study microbes-epithelium interactions. | the gut, particularly the colon, is the host of approximately 1000 bacterial species, the so-called gut microbiota. the relationship between the gut microbiota and the host is symbiotic and mutualistic, influencing many aspects of the biology of the host. this homeostatic balance can be disrupted by enteric pathogens, such as shigella flexneri or listeria monocytogenes, which are able to invade the epithelial layer and consequently subvert physiological functions. to study the host-microbe inter ... | 2016 | 27628134 |
| microbial pathogenesis meets biomechanics. | introducing concepts from soft matter physics and mechanics has largely contributed to our understanding of a variety of biological processes. in this review, we argue that this holds true for bacterial pathogenesis. we base this argument on three examples of bacterial pathogens and their interaction with host cells during infection: (i) shigella flexneri exploits actin-dependent forces to come into close contact with epithelial cells prior to invasion of the epithelium; (ii) neisseria meningiti ... | 2016 | 26849533 |
| gallic acid conjugated with gold nanoparticles: antibacterial activity and mechanism of action on foodborne pathogens. | foodborne pathogens, including plesiomonas shigelloides and shigella flexneri b, are the major cause of diarrheal endemics worldwide. antibiotic drug resistance is increasing. therefore, bioactive compounds with antibacterial activity, such as gallic acid (ga), are needed. gold nanoparticles (aunps) are used as drug delivery agents. this study aimed to conjugate and characterize aunp-ga and to evaluate the antibacterial activity. aunp was conjugated with ga, and the core-shell structures were ch ... | 2016 | 27555764 |
| safety and immunogenicity of a candidate bioconjugate vaccine against shigella flexneri 2a administered to healthy adults: a single-blind, randomized phase i study. | several candidate vaccines against shigella spp. are in development, but the lack of a clear correlate of protection from challenge with the induction of adequate immune responses among the youngest age groups in the developing world has hampered shigella vaccine development over the past several decades. bioconjugation technology, exploited here for an shigella flexneri 2a candidate vaccine, offers a novel and potentially cost-effective way to develop and produce vaccines against a major pathog ... | 2016 | 27581434 |
| gallesia integrifolia (spreng.) harms: in vitro and in vivo antibacterial activities and mode of action. | gallesia integrifolia (phytolaccaceae) is commonly known as "pau-d'alho" in brazil or "garlic plant" due to the strong scent of garlic peculiar to all parts of the plant. the bark decoction is used for the treatment of microbial infections among other diseases by different ethnic groups in brazil, peruvian amazonians, bolivia and mosetene indians. this study aimed to advance in the antibacterial activity and characterize the mode of action of the hydroethanolic extract of the inner stem bark of ... | 2016 | 26945980 |
| conserved transmembrane glycine residues in the shigella flexneri polysaccharide co-polymerase protein wzzb influence protein-protein interactions. | the o antigen (oag) component of lipopolysaccharides (lps) is crucial for virulence and oag chain-length regulation is controlled by the polysaccharide co-polymerase class 1 (pcp1) proteins. crystal structure analyses indicate that structural conservation among pcp1 proteins is highly maintained, however the mechanism of oag modal-chain-length control remains to be fully elucidated. shigella flexneri pcp1 protein wzzbsf confers a modal-chain length of 10-17 oag repeat units (rus), whereas the sa ... | 2016 | 27028755 |
| shigellosis in nepal: 13 years review of nationwide surveillance. | shigella is a major cause of gastroenteritis especially in children. in developing countries, the incidence is frequent and results are often life threatening. changing epidemiology and emerging antibiotic resistance warrants continuous monitoring of susceptibility. the present study highlights the changing epidemiology and drug resistance patterns of shigella isolated at different hospitals of nepal over a period of 13 years (jan. 2003-dec. 2015). | 2016 | 27814742 |
| a review on sero diversity and antimicrobial resistance patterns of shigella species in africa, asia and south america, 2001-2014. | shigella, gram negative bacterium, is responsible for shigellosis/bacillary dysentery. it is a global concern although it predominates in developing countries. these are shigella dysenteriae, shigella flexneri, shigella boydii and shigella sonnei. drug resistance by shigella species is another headache of the world. therefore; this study aimed to review distribution of shigella serogroups and their antimicrobial patterns carried out in africa, asia and south america. | 2016 | 27576729 |
| molecular characterisation of quinolone-resistant shigella strains isolated in tehran, iran. | over the past few years, the number of shigella strains resistant to nalidixic acid has increased and has made the selection of effective antimicrobial therapy more difficult. the purpose of this study was to investigate the molecular mechanism of quinolone resistance in shigella strains. shigella strains isolated from 1100 diarrhoeal patients in tehran, iran, were assessed for their susceptibility to nalidixic acid prior to pcr-rflp and sequence analysis of their quinolone resistance genes. amo ... | 2016 | 27436462 |
| multi-locus sequence type analysis of shigellas pp. isolates from tehran, iran. | strains of shigella spp. can cause shigellosis, or bacillary dysentery. that is a public health problem worldwide. the aim of this study was to describe the population structure and genetic relatedness of multidrug resistant s. sonnei and s. flexneri isolated during a one year period from children with diarrhea in tehran, iran. | 2016 | 28149488 |
| azithromycin-nonsusceptible shigella flexneri 3a in men who have sex with men, taiwan, 2015-2016. | we report an outbreak of azithromycin-nonsusceptible shigella flexneri 3a infection in taiwan associated with men who have sex with men. the bacterial strains belonged to the sublineage a of a recently reported outbreak lineage associated with men who have sex with men, characterized by reduced azithromycin susceptibility and circulation in shigellosis low-risk regions. | 2016 | 28098533 |
| [epidemiology and etiology of bacillary dysentery in xinjiang uigur autonomous region, 2004-2014]. | objective: to understand the epidemiological and etiological characteristics of bacillary dysentery in xinjiang uigur autonomous region (xinjiang) during 2004-2014, and provide evidence for the prevention and control of bacillary dysentery. methods: descriptive epidemiological analysis was conducted by using the incidence data of bacillary dysentery in xinjiang during 2004-2014 and the serotyping and the antibiotic susceptibility test of the pathogens isolated were performed. results: a total of ... | 2016 | 28072950 |
| finding potential therapeutic targets against shigella flexneri through proteome exploration. | background:shigella flexneri is a gram negative bacteria that causes the infectious disease "shigellosis." s. flexneri is responsible for developing diarrhea, fever, and stomach cramps in human. antibiotics are mostly given to patients infected with shigella. resistance to antibiotics can hinder its treatment significantly. upon identification of essential therapeutic targets, vaccine and drug could be effective therapy for the treatment of shigellosis. methods: the study was designed for the id ... | 2016 | 27920755 |
| anticancer and antibacterial secondary metabolites from the endophytic fungus penicillium sp. cam64 against multi-drug resistant gram-negative bacteria. | the emergence of multiple-drug resistance bacteria has become a major threat and thus calls for an urgent need to search for new effective and safe anti-bacterial agents. | 2016 | 27917206 |
| injections of predatory bacteria work alongside host immune cells to treat shigella infection in zebrafish larvae. | bdellovibrio bacteriovorus are predatory bacteria that invade and kill a range of gram-negative bacterial pathogens in natural environments and in vitro [1, 2]. in this study, we investigated bdellovibrio as an injected, antibacterial treatment in vivo, using zebrafish (danio rerio) larvae infected with an antibiotic-resistant strain of the human pathogen shigella flexneri. when injected alone, bdellovibrio can persist for more than 24 hr in vivo yet exert no pathogenic effects on zebrafish larv ... | 2016 | 27889262 |
| shigella vaccine development: finding the path of least resistance. | shigella spp. represent the second most common etiologic pathogen causing childhood diarrhea in developing countries. there are no licensed shigella vaccines, and progress for such vaccines has been limited. in this issue of clinical and vaccine immunology, riddle and colleagues (m. s. riddle, r. w. kaminski, c. di paolo, c. k. porter, r. l. gutierrez, et al., clin vaccine immunol 23:908-917, 2016, http://dx.doi.org/10.1128/cvi.00224-16) report results from a phase i study of a parenterally admi ... | 2016 | 27707764 |
| mitochondria promote septin assembly into cages that entrap shigella for autophagy. | septins are cytoskeletal proteins implicated in cytokinesis and host-pathogen interactions. during macroautophagy/autophagy of shigella flexneri, septins assemble into cage-like structures to entrap actin-polymerizing bacteria and restrict their dissemination. how septins assemble to entrap bacteria is not fully known. we discovered that mitochondria support septin cage assembly to promote autophagy of shigella. consistent with roles for the cytoskeleton in mitochondrial dynamics, we showed that ... | 2016 | 27629779 |
| novel mutations in quinolone resistance-determining regions of gyra, gyrb, parc and pare in shigella flexneri clinical isolates from eastern chinese populations between 2001 and 2011. | the aim of this study was to evaluate the prevalence of fluoroquinolone resistance and mechanisms of selected fluoroquinolone resistance in shigella flexneri isolates. a total of 624 s. flexneri strains isolated between 2001 and 2011 in jiangsu province of china were analysed for their fluoroquinolone susceptibility. the quinolone resistance-determining region of gyra, gyrb, parc and pare were amplified and sequenced. in general, 90.5 % of s. flexneri exhibited resistance to nalidixic acid. the ... | 2016 | 27620866 |
| shigella flexneri suppresses nf-κb activation by inhibiting linear ubiquitin chain ligation. | the linear ubiquitin chain assembly complex (lubac) is a multimeric e3 ligase that catalyses m1 or linear ubiquitination of activated immune receptor signalling complexes (rscs). mutations that disrupt linear ubiquitin assembly lead to complex disease pathologies including immunodeficiency and autoinflammation in both humans and mice, but microbial toxins that target lubac function have not yet been discovered. here, we report the identification of two homologous shigella flexneri type iii secre ... | 2016 | 27572974 |
| shigella flexneri modulates stress granule composition and inhibits stress granule aggregation. | 2016 | 27870195 | |
| the changing epidemiology of bacillary dysentery and characteristics of antimicrobial resistance of shigella isolated in china from 2004-2014. | bacillary dysentery caused by bacteria of the genus shigella is a significant public health problem in developing countries such as china. the objective of this study was to analyze the epidemiological pattern of bacillary dysentery, the diversity of the causative agent, and the antimicrobial resistance patterns of shigella spp. for the purpose of determining the most effective allocation of resources and prioritization of interventions. | 2016 | 27863468 |
| antibacterial and cytotoxic cytochalasins from the endophytic fungus phomopsis sp. harbored in garcinia kola (heckel) nut. | the continuous emergence of multidrug-resistant (mdr) bacteria drastically reduced the efficacy of our antibiotic armory and consequently, increased the frequency of therapeutic failure. the search for bioactive constituents from endophytic fungi against mdr bacteria became a necessity for alternative and promising strategies, and for the development of novel therapeutic solutions. we report here the isolation and structure elucidation of antibacterial and cytotoxic compounds from phomopsis sp., ... | 2016 | 27842536 |
| decreased susceptibility to azithromycin among clinical shigella isolates from china. | the aim of this study was to detect the decreased susceptibility to azithromycin (dsa) and associated mechanisms in shigella from china. three hundred and ninety-two shigella isolates, including 134 shigella flexneri and 258 shigella sonnei isolates, were examined for minimum inhibitory concentrations (mics) and zone sizes to azithromycin by broth microdilution and disk diffusion methods, respectively. the mics were compared with corresponding zone diameters to find whether there was uniformity ... | 2016 | 27841958 |
| intrinsic jnk-mapk pathway involvement requires daf-16-mediated immune response during shigella flexneri infection in c. elegans. | the c-jun n-terminal kinase-mitogen-activated protein kinase (jnk-mapk) pathway assists in modulating signals for growth, survival, and metabolism, thereby coordinating many cellular events during normal and stress conditions. to understand the role of the jnk-mapk pathway during bacterial infection, an in vivo model organism caenorhabditis elegans was used. in order to check the involvement of the jnk-mapk pathway, the survival rate of c. elegans wild type (wt), and jnk-mapk pathway mutant worm ... | 2016 | 27838822 |
| of men not mice: bactericidal/permeability-increasing protein expressed in human macrophages acts as a phagocytic receptor and modulates entry and replication of gram-negative bacteria. | macrophages as immune cells prevent the spreading of pathogens by means of active phagocytosis and killing. we report here the presence of an antimicrobial protein, bactericidal/permeability-increasing protein (bpi) in human macrophages, which actively participates in engulfment and killing of gram-negative pathogens. our studies revealed increased expression of bpi in human macrophages during bacterial infection and upon stimulation with various pathogen-associated molecular patterns, viz., lps ... | 2016 | 27822215 |
| deletion of toxin-antitoxin systems in the evolution of shigella sonnei as a host-adapted pathogen. | pathogenic shigella spp. are the leading cause of bacterial dysentery, with shigella flexneri and shigella sonnei accounting for around 90% of cases worldwide. although s. flexneri causes most disease in low-income countries (following ingestion of contaminated food and/or water), s. sonnei predominates in wealthy countries and is mainly spread from person to person. although both species contain a large virulence plasmid, pinv, that is essential for the organism to cause disease, little is know ... | 2016 | 27819667 |
| social buffering and contact transmission: network connections have beneficial and detrimental effects on shigella infection risk among captive rhesus macaques. | in social animals, group living may impact the risk of infectious disease acquisition in two ways. on the one hand, social connectedness puts individuals at greater risk or susceptibility for acquiring enteric pathogens via contact-mediated transmission. yet conversely, in strongly bonded societies like humans and some nonhuman primates, having close connections and strong social ties of support can also socially buffer individuals against susceptibility or transmissibility of infectious agents. ... | 2016 | 27812426 |
| the synthesis of ospd3 (shet2) in shigella flexneri is independent of ospc1. | shigella flexneri is a gram-negative pathogen that invades the colonic epithelium and causes millions of cases of watery diarrhea or bacillary dysentery predominately in children under the age of 5 years in developing countries. the effector shigella enterotoxin 2 (shet2), or ospd3, is encoded by the sen or ospd3 gene on the virulence plasmid. previous literature has suggested that ospd3 is in an operon downstream of the ospc1 gene, and expression of both genes is controlled by a promoter upstre ... | 2016 | 27657187 |
| diverted recycling-shigella subversion of rabs. | small gtpases of the rab protein family control intracellular vesicular trafficking to allow their communication and maintenance. it is a common strategy for intracellular bacteria to exploit these pathways to shape their respective niches for survival. the subversion of rabs for the generation of an intracellular environment favoring the pathogen has been described almost exclusively for intracellular bacteria that reside within bacterial containing vacuoles (bcvs). however, less is known about ... | 2016 | 27763815 |
| characterization of a multicomponent live, attenuated shigella flexneri vaccine. | shigella flexneri is a leading cause of diarrheal disease in children under five in developing countries. there is currently no licensed vaccine and broad spectrum protection requires coverage of multiple serotypes. the live attenuated vaccines cvd 1213 and cvd 1215 were derived from two prominent s. flexneri serotypes: s. flexneri 3a and s. flexneri 6. to provide broad-spectrum immunity, they could be combined with cvd 1208s, a s. flexneri 2a strain that demonstrated promising results in phase ... | 2016 | 27106253 |
| an approach to identify and characterize a subunit candidate shigella vaccine antigen. | shigellosis remains a serious issue throughout the developing countries, particularly in children under the age of 5. numerous strategies have been tested to develop vaccines targeting shigellosis; unfortunately despite several years of extensive research, no safe, effective, and inexpensive vaccine against shigellosis is available so far. here, we illustrate in detail an approach to identify and establish immunogenic outer membrane proteins from shigella flexneri 2a as subunit vaccine candidate ... | 2016 | 27076146 |
| macrophage apoptosis triggered by ipad from shigella flexneri. | shigellosis, a potentially severe bacillary dysentery, is an infectious gastrointestinal disease caused by shigella spp. shigella invades the human colonic epithelium and avoids clearance by promoting apoptosis of resident immune cells in the gut. this process is dependent on the shigella type iii secretion system (t3ss), which injects effector proteins into target cells to alter their normal cellular functions. invasion plasmid antigen d (ipad) is a structural component that forms a complex at ... | 2016 | 27068089 |
| crystal structure of the substrate-recognition domain of the shigella e3 ligase ipah9.8. | infectious diseases caused by bacteria have significant impacts on global public health. during infection, pathogenic bacteria deliver a variety of virulence factors, called effectors, into host cells. the shigella effector ipah9.8 functions as an ubiquitin ligase, ubiquitinating the nf-κb essential modulator (nemo)/ikk-γ to inhibit host inflammatory responses. ipah9.8 contains leucine-rich repeats (lrrs) involved in substrate recognition and an e3 ligase domain. to elucidate the structural basi ... | 2016 | 27050259 |
| bacteriophage tailspikes and bacterial o-antigens as a model system to study weak-affinity protein-polysaccharide interactions. | understanding interactions of bacterial surface polysaccharides with receptor protein scaffolds is important for the development of antibiotic therapies. the corresponding protein recognition domains frequently form low-affinity complexes with polysaccharides that are difficult to address with experimental techniques due to the conformational flexibility of the polysaccharide. in this work, we studied the tailspike protein (tsp) of the bacteriophage sf6. sf6tsp binds and hydrolyzes the high-rham ... | 2016 | 27045683 |
| linear synthesis of the hexasaccharide related to the repeating unit of the o-antigen from shigella flexneri serotype 1d (i: 7,8). | total synthesis of the hexasaccharide repeating unit of the o-antigen from shigella flexneri serotype 1d (i: 7,8), α-d-glcp-(1→3)-α-l-rhap-(1→2)-α-l-rhap-(1→3)-α-l-rhap-(1→3)-[α-d-glcp-(1→4)]-β-d-glcpnac, is reported by following a linear strategy. the target hexasaccharide was synthesized by sequential glycosylations of suitably protected monosaccharide derivatives prepared from commercially available monosaccharides through rational protecting group manipulations. stereoselective glycosylation ... | 2016 | 27043468 |
| molecular and cellular mechanisms of shigella flexneri dissemination. | the intracellular pathogen shigella flexneri is the causative agent of bacillary dysentery in humans. the disease is characterized by bacterial invasion of intestinal cells, dissemination within the colonic epithelium through direct spread from cell to cell, and massive inflammation of the intestinal mucosa. here, we review the mechanisms supporting s. flexneri dissemination. the dissemination process primarily relies on actin assembly at the bacterial pole, which propels the pathogen throughout ... | 2016 | 27014639 |
| a novel small rna regulates tolerance and virulence in shigella flexneri by responding to acidic environmental changes. | shigella flexneri is an important cause of bacillary dysentery in developing countries. small regulatory rnas (srnas) play essential roles in diverse cellular processes. we found a novel srna ssr1 based on rt-pcr, northern blot, and 5'race in s. flexneri. ssr1 responds to acidic environmental changes, as shown by a strong linear correlation between the ph value and ssr1 expression (r = 0.785, p < 0.05) using the qrt-pcr method. deletion of ssr1 results in growth retardation at ph values ranging ... | 2016 | 27014636 |
| evaluation of molecular methods for serotyping shigella flexneri. | shigella flexneri can be phenotypically serotyped using antisera raised to type-specific somatic antigens and group factor antigens and genotypically serotyped using pcr targeting o-antigen synthesis or modification genes. the aim of this study was to evaluate a real-time pcr for serotyping s. flexneri and to use whole-genome sequencing (wgs) to investigate the phenotypic and genotypic serotype identifications. of the 244 cultures tested retrospectively, 226 (92.6%) had concordant results betwee ... | 2016 | 26984974 |
| spa47 is an oligomerization-activated type three secretion system (t3ss) atpase from shigella flexneri. | gram-negative pathogens often use conserved type three secretion systems (t3ss) for virulence. the shigella type three secretion apparatus (t3sa) penetrates the host cell membrane and provides a unidirectional conduit for injection of effectors into host cells. the protein spa47 localizes to the base of the apparatus and is speculated to be an atpase that provides the energy for t3sa formation and secretion. here, we developed an expression and purification protocol, producing active spa47 and p ... | 2016 | 26947936 |
| visualizing the translocation and localization of bacterial type iii effector proteins by using a genetically encoded reporter system. | bacterial type iii secretion system (t3ss) effector proteins are critical determinants of infection for many animal and plant pathogens. however, monitoring of the translocation and delivery of these important virulence determinants has proved to be technically challenging. here, we used a genetically engineered lov (light-oxygen-voltage) sensing domain derivative to monitor the expression, translocation, and localization of bacterial t3ss effectors. we found the escherichia coli o157:h7 bacteri ... | 2016 | 26921426 |
| a synthetic carbohydrate conjugate vaccine candidate against shigellosis: improved bioconjugation and impact of alum on immunogenicity. | conjugation chemistry is among the most important parameters governing the efficacy of glycoconjugate vaccines. high robustness is required to ensure high yields and batch to batch reproducibility. herein, we have established a robust bioconjugation protocol based on the thiol-maleimide addition. major variables were determined and acceptable margins were investigated for a synthetic pentadecasaccharide-tetanus toxoid conjugate, which is a promising vaccine candidate against shigella flexneri se ... | 2016 | 26918643 |
| prevalence and virulence genes of shigella spp. isolated from patients with diarrhea in rosario, argentina. | the aim of this study was to determine the prevalence and virulence factors of shigella species isolated from patients with diarrhea. shigella species were isolated from 1,022 stool samples collected from different hospitals in rosario, argentina. the isolates were characterized using phenotypic tests, serotyping, and detection of virulence genes by pcr. one hundred strains (9.8% of samples collected) of shigella were isolated. shigella flexneri was the most frequently identified species (74%), ... | 2016 | 26902216 |
| evaluation of the safety, tolerability, and immunogenicity of an oral, inactivated whole-cell shigella flexneri 2a vaccine in healthy adult subjects. | shigella causes high morbidity and mortality worldwide, but there is no licensed vaccine for shigellosis yet. we evaluated the safety and immunogenicity of a formalin-inactivated whole-cell shigella flexneri2a vaccine, sf2awc, given orally to adult volunteers. in a double-blind, placebo-controlled trial, 82 subjects were randomized to receive three doses of vaccine in dose escalation (2.6 ± 0.8 × 10(8), × 10(9), × 10(10), and × 10(11)vaccine particles/ml). vaccine safety was actively monitored, ... | 2016 | 26865592 |
| structural insights into the fluoroquinolone resistance mechanism of shigella flexneri dna gyrase and topoisomerase iv. | traveler's diarrhea (td) is an important public health concern that can result from a variety of intestinal pathogens, including bacteria, parasites, and virus. a number of antibiotics are being used to cure td, but due to widespread use of these antibiotics, the pathogens are becoming resistant to them. in this work, we performed docking studies of dna gyrasea (gyra) and topoisomerase iv (parc) of shigella flexneri and their mutants with two different fluoroquinolones, ciprofloxacin and norflox ... | 2016 | 26859259 |
| structural analysis of the active site architecture of the vapc toxin from shigella flexneri. | the vapc toxin from the shigella flexneri 2a virulence plasmid pmysh6000 belongs to the pin domain protein family, which is characterized by a conserved fold with low amino acid sequence conservation. the toxin is a bona fide mg(2+) -dependent ribonuclease and has been shown to target initiator trna(fmet) in vivo. here, we present crystal structures of active site catalytic triad mutants d7a, d7n, and d98n of the vapc toxin in absence of antitoxin. in all structures, as well as in solution, vapc ... | 2016 | 26833558 |
| pi5p triggers icam-1 degradation in shigella infected cells, thus dampening immune cell recruitment. | shigella flexneri, the pathogen responsible for bacillary dysentery, has evolved multiple strategies to control the inflammatory response. here, we show that shigella subverts the subcellular trafficking of the intercellular adhesion molecule-1 (icam-1), a key molecule in immune cell recruitment, in a mechanism dependent on the injected bacterial enzyme ipgd and its product, the lipid mediator pi5p. overexpression of ipgd, but not a phosphatase dead mutant, induced the internalization and the de ... | 2016 | 26776508 |
| flexibility at a glycosidic linkage revealed by molecular dynamics, stochastic modeling, and (13)c nmr spin relaxation: conformational preferences of α-l-rhap-α-(1 → 2)-α-l-rhap-ome in water and dimethyl sulfoxide solutions. | the monosaccharide l-rhamnose is common in bacterial polysaccharides and the disaccharide α-l-rhap-α-(1 → 2)-α-l-rhap-ome represents a structural model for a part of shigella flexneri o-antigen polysaccharides. utilization of [1'-(13)c]-site-specific labeling in the anomeric position at the glycosidic linkage between the two sugar residues facilitated the determination of transglycosidic nmr (3)jch and (3)jcc coupling constants. based on these spin-spin couplings the major state and the conforma ... | 2016 | 26741055 |
| shigella infections: a two year experience in cancer patients. | to identify clinical and microbiological characteristics of shigella infections among cancer patients. | 2016 | 26712178 |
| bacterial e3 ubiquitin ligase ipah4.5 of shigella flexneri targets tbk1 to dampen the host antibacterial response. | ifn regulatory factors play a pivotal role in many cellular processes, including inflammatory and immune responses. their activation is tightly regulated by tank-binding kinase 1 (tbk1). in response to microbial components, tbk1 activates ifn regulatory factor 3 (irf3) and cytokine expression. in this article, we show that tbk1 is a novel target of the ipah4.5 protein, a shigella type iii effector possessing e3 ubiquitin ligase activity. remarkably, ipah4.5 interacts with tbk1 and promotes its k ... | 2016 | 26700764 |
| clinical implications of reduced susceptibility to fluoroquinolones in paediatric shigella sonnei and shigella flexneri infections. | we aimed to quantify the impact of fluoroquinolone resistance on the clinical outcome of paediatric shigellosis patients treated with fluoroquinolones in southern vietnam. such information is important to inform therapeutic management for infections caused by this increasingly drug-resistant pathogen, responsible for high morbidity and mortality in young children globally. | 2016 | 26679253 |
| the architecture of the cytoplasmic region of type iii secretion systems. | type iii secretion systems (t3sss) are essential devices in the virulence of many gram-negative bacterial pathogens. they mediate injection of protein effectors of virulence from bacteria into eukaryotic host cells to manipulate them during infection. t3sss involved in virulence (vt3sss) are evolutionarily related to bacterial flagellar protein export apparatuses (ft3sss), which are essential for flagellar assembly and cell motility. the structure of the external and transmembrane parts of both ... | 2016 | 27686865 |
| proteomic analysis of shigella virulence effectors secreted under different conditions. | there are a series of novel effector molecules secreted by the type three secretion system (t3ss) of shigella spp. reported in recent years. in this study, a proteomic approach is applied to study t3ss effectors systematically. first, proteins secreted by the s. flexneri wild-type strain after congo red (cr) induction are separated and identified using two-dimensional electrophoresis (2-de) to display the relative abundance of all kinds of early effectors for the first time. then, a gene deletio ... | 2016 | 27666981 |
| evolved populations of shigella flexneri phage sf6 acquire large deletions, altered genomic architecture, and faster life cycles. | genomic architecture is the framework within which genes and regulatory elements evolve and where specific constructs may constrain or potentiate particular adaptations. one such construct is evident in phages that use a headful packaging strategy that results in progeny phage heads packaged with dna until full rather than encapsidating a simple unit-length genome. here, we investigate the evolution of the headful packaging phage sf6 in response to barriers that impede efficient phage adsorption ... | 2016 | 27497318 |
| molecular diagnosis and anti-microbial resistance patterns among shigella spp. isolated from patients with diarrhea. | this study aims to determine the serogroup distribution and molecular diagnosis, as well as antimicrobial resistance profiles among shigella spp. isolated from patients with diarrhea in kerman, southeast of iran. | 2016 | 27458513 |
| unprecedented abundance of protein tyrosine phosphorylation modulates shigella flexneri virulence. | evidence is accumulating that protein tyrosine phosphorylation plays a crucial role in the ability of important human bacterial pathogens to cause disease. while most works have concentrated on its role in the regulation of a major bacterial virulence factor, the polysaccharide capsule, recent studies have suggested a much broader role for this post-translational modification. this prompted us to investigate protein tyrosine phosphorylation in the human pathogen shigella flexneri. we first compl ... | 2016 | 27380737 |
| detailed investigation of the immunodominant role of o-antigen stoichiometric o-acetylation as revealed by chemical synthesis, immunochemistry, solution conformation and std-nmr spectroscopy for shigella flexneri 3a. | shigella flexneri 3a causes bacillary dysentery. its o-antigen has the {2)-[α-d-glcp-(1→3)]-α-l-rhap-(1→2)-α-l-rhap-(1→3)-[ac→2]-α-l-rhap-(1→3)-[ac→6]≈40 % -β-d-glcpnac-(1→} ([(e)abac cac d]) repeating unit, and the non-o-acetylated equivalent defines s. flexneri x. propyl hepta-, octa-, and decasaccharides sharing the (e')a'bac cd(e)a sequence, and their non-o-acetylated analogues were synthesized from a fully protected bac cd(e)a allyl glycoside. the stepwise introduction of orthogonally prote ... | 2016 | 27376496 |
| molecular characterization and analysis of high-level multidrug-resistance of shigella flexneri serotype 4s strains from china. | to conduct the first comprehensive analysis of shigella flexneri serotype 4s, a novel serotype found in 2010, we identified 24 serotype 4s isolates from 1973 shigellosis cases in china (2002-2014). the isolates were characterized by single nucleotide polymorphism (snp) phylogenetic analysis, pulsed-field gel electrophoresis (pfge) and multilocus sequence typing (mlst) to determine their genetic relatedness, and analysed further for their antimicrobial susceptibilities and antimicrobial resistanc ... | 2016 | 27374009 |
| carbbuilder: software for building molecular models of complex oligo- and polysaccharide structures. | carbbuilder is a portable software tool for producing three-dimensional molecular models of carbohydrates from the simple text specification of a primary structure. carbbuilder can generate a wide variety of carbohydrate structures, ranging from monosaccharides to large, branched polysaccharides. version 2.0 of the software, described in this article, supports monosaccharides of both mammalian and bacterial origin and a range of substituents for derivatization of individual sugar residues. this ... | 2016 | 27317625 |
| shigella flexneri modulates stress granule composition and inhibits stress granule aggregation. | invasion and multiplication of the facultative, cytosolic, enteropathogen shigella flexneri within the colonic epithelial lining leads to an acute inflammatory response, fever and diarrhea. during the inflammatory process, infected cells are subjected to numerous stresses including heat, oxidative stress and genotoxic stress. the evolutionarily conserved pathway of cellular stress management is the formation of stress granules that store translationally inactive cellular mrnas and interfere with ... | 2016 | 27282465 |
| monoclonal antibodies to shigella lipopolysaccharide are useful for vaccine production. | there is a significant need for an effective multivalent shigella vaccine that targets the most prevalent serotypes. most shigella vaccines under development utilize serotype-specific lipopolysaccharides (lpss) as a major component based on protection and epidemiological data. as vaccine formulations advance from monovalent to multivalent, assays and reagents need to be developed to accurately and reproducibly quantitate the amount of lpss from multiple serotypes in the final product. to facilit ... | 2016 | 27280622 |
| mitochondria mediate septin cage assembly to promote autophagy of shigella. | septins, cytoskeletal proteins with well-characterised roles in cytokinesis, form cage-like structures around cytosolic shigella flexneri and promote their targeting to autophagosomes. however, the processes underlying septin cage assembly, and whether they influence s. flexneri proliferation, remain to be established. using single-cell analysis, we show that the septin cages inhibit s. flexneri proliferation. to study mechanisms of septin cage assembly, we used proteomics and found mitochondria ... | 2016 | 27259462 |
| prevalence, resistance patterns, and characterization of integrons of shigella flexneri isolated from jiangsu province in china, 2001-2011. | to provide the epidemiology, resistance pattern, and characterization of integrons in shigella flexneri isolated between 2001 and 2011 in jiangsu province. | 2016 | 27220330 |
| macropinosomes are key players in early shigella invasion and vacuolar escape in epithelial cells. | intracellular pathogens include all viruses, many bacteria and parasites capable of invading and surviving within host cells. key to survival is the subversion of host cell pathways by the pathogen for the purpose of propagation and evading the immune system. the intracellular bacterium shigella flexneri, the causative agent of bacillary dysentery, invades host cells in a vacuole that is subsequently ruptured to allow growth of the pathogen within the host cytoplasm. s. flexneri invasion has bee ... | 2016 | 27182929 |
| resistant shigella strains in refugees, august-october 2015, greece. | shigellosis is endemic in most developing countries and thus a known risk in refugees and internally displaced persons. in 2015, a massive influx of refugees into greece, due to the political crisis in the middle east, led to the development of appropriate conditions for outbreaks of communicable diseases as shigellosis. we present a cluster of 16 shigellosis cases in refugees, detected by the implementation of a syndromic notification system in one transit centre in athens, between 20 august an ... | 2016 | 27180973 |
| mxia, mxic and ipad regulate substrate selection and secretion mode in the t3ss of shigella flexneri. | type iii secretion systems (t3sss) are central virulence devices for many gram-negative bacterial pathogens of humans, animals & plants. upon physical contact with eukaryotic host cells, they translocate virulence-mediating proteins, known as effectors, into them during infection. t3sss are gated from the outside by host-cell contact and from the inside via two cytoplasmic negative regulators, mxic and ipad in shigella flexneri, which together control the effector secretion hierarchy. their abse ... | 2016 | 27171191 |
| the multivalent adhesion molecule sso1327 plays a key role in shigella sonnei pathogenesis. | shigella sonnei is a bacterial pathogen and causative agent of bacillary dysentery. it deploys a type iii secretion system to inject effector proteins into host epithelial cells and macrophages, an essential step for tissue invasion and immune evasion. although the arsenal of bacterial effectors and their cellular targets have been studied extensively, little is known about the prerequisites for deployment of type iii secreted proteins during infection. here, we describe a novel s. sonnei adhesi ... | 2016 | 26481305 |
| invasive shigellosis in msm. | shigella flexneri is an emerging pathogen in men who have sex with men (msm); recent outbreaks related to sexual practices have been noted in this population in the uk and other developed countries. while the majority of cases of shigellosis present with gastroenteritis, some vulnerable patients with underlying immunosuppression can develop complications like bacteraemia and may present atypically as an acute surgical emergency. this case report highlights such a case of s. flexneri bacteraemia ... | 2016 | 26429891 |
| anoxia and glucose supplementation preserve neutrophil viability and function. | functional studies of human neutrophils and their transfusion for clinical purposes have been hampered by their short life span after isolation. here, we demonstrate that neutrophil viability is maintained for 20 hours in culture media at 37°c under anoxic conditions with 3 mm glucose and 32 μg/ml dimethyloxalylglycine supplementation, as evidenced by stabilization of mcl-1, proliferating cell nuclear antigen (pcna), and pro-caspase-3. notably, neutrophil morphology (nucleus shape and cell-surfa ... | 2016 | 27402974 |
| anthropometry in sex chromosome abnormality. | 2016 | 4829429 | |
| [sydenham's chorea]. | 2016 | 4944902 | |
| blood histamine, basophil counts and trace elements in the schizophrenias. | 2016 | 5052331 | |
| mechanism of selection and decision-making in therapeutic abortion. | 2016 | 5088001 | |
| [in memoriam dr ante jamnicki]. | 2016 | 4943942 | |
| [double-blind study of the antidepressive drugs (noxiptilin-imipramine)]. | 2016 | 4936793 | |
| why cholera may be important to doctors in the u.s. | 2016 | 4935860 | |
| two minutes with diabetes. | 2016 | 4810611 | |
| [the intraoral registration of the centric relation in the edentulous jaw in connection with the closed impression technic by means of the sr-ivotray method]. | 2016 | 4906692 |