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serotype-conversion in shigella flexneri: identification of a novel bacteriophage, sf101, from a serotype 7a strain.shigella flexneri is the major cause of bacillary dysentery in the developing countries. the lipopolysaccharide (lps) o-antigen of s. flexneri plays an important role in its pathogenesis and also divides s. flexneri into 19 serotypes. all the serotypes with an exception for serotype 6 share a common o-antigen backbone comprising of n-acetylglucosamine and three rhamnose residues. different serotypes result from modification of the basic backbone conferred by phage-encoded glucosyltransferase and ...201425174528
linear synthesis of the branched pentasaccharide repeats of o-antigens from shigella flexneri 1a and 1b demonstrating the major steric hindrance associated with type-specific glucosylation.shigella flexneri serotypes 1b and 1a are gram-negative enteroinvasive bacteria causing shigellosis in humans. the o-antigen from s. flexneri 1b is a { → 2)-[3ac/4ac]-α-l-rhap-(1 → 2)-α-l-rhap-(1 → 3)-[2ac]-α-l-rhap-(1 → 3)-[α-d-glcp-(1 → 4)]-β-d-glcpnac-(1 → }n branched polysaccharide ({(ac)ab(ac)c(e)d}n). it is identical to that from s. flexneri 1a, except for the 2c-acetate. a concise synthesis of the disaccharide ed, trisaccharides (ac)c(e)d and c(e)d, tetrasaccharides b(ac)c(e)d and bc(e)d, ...201425141906
multidrug resistant shigella flexneri : a rare case of septicemia in an infant.shigellosis is still an important public health problem in developing and under-developed countries. it may lead to rare but potentially fatal various extra intestinal complications like septicemia, involvement of cns, urinary tract and liver especially in young malnourished children. the disease is difficult to prevent as only few bacteria are required for causing infection and there is increasing infection with multi drug resistant strains. a 6-month-old infant developed septicemia caused by m ...201425120984
the serine/threonine kinase stk11 promotes shigella flexneri dissemination through establishment of cell-cell contacts competent for tyrosine kinase signaling.shigella flexneri is an intracellular pathogen that disseminates in the intestinal epithelium by displaying actin-based motility. we found that although s. flexneri displayed comparable actin-based motilities in the cytosols of hela229 and ht-29 epithelial cell lines, the overall dissemination process was much more efficient in ht-29 cells. time-lapse microscopy demonstrated that as motile bacteria reached the cell cortex in ht-29 cells, they formed membrane protrusions that resolved into vacuol ...201425114112
influence of oligomerization state on the structural properties of invasion plasmid antigen b from shigella flexneri in the presence and absence of phospholipid membranes.shigella flexneri causes bacillary dysentery, an important cause of mortality among children in the developing world. shigella secretes effector proteins via its type iii secretion system (t3ss) to promote bacterial uptake into human colonic epithelial cells. the t3ss basal body spans the bacterial cell envelope anchoring a surface-exposed needle. a pentamer of invasion plasmid antigen d lies at the nascent needle tip and invasion plasmid antigen b (ipab) is recruited into the needle tip complex ...201425103195
sumoylation controls host anti-bacterial response to the gut invasive pathogen shigella flexneri.shigella flexneri, the etiological agent of bacillary dysentery, invades the human colonic epithelium and causes its massive inflammatory destruction. little is known about the post-translational modifications implicated in regulating the host defense pathway against shigella. here, we show that sumo-2 impairs shigella invasion of epithelial cells in vitro. using mice haploinsufficient for the sumo e2 enzyme, we found that sumoylation regulates intestinal permeability and is required to restrict ...201425097252
bid-dependent release of mitochondrial smac dampens xiap-mediated immunity against shigella.the x-linked inhibitor of apoptosis protein (xiap) is a potent caspase inhibitor, best known for its anti-apoptotic function in cancer. during apoptosis, xiap is antagonized by smac, which is released from the mitochondria upon caspase-mediated activation of bid. recent studies suggest that xiap is involved in immune signaling. here, we explore xiap as an important mediator of an immune response against the enteroinvasive bacterium shigella flexneri, both in vitro and in vivo. our data demonstra ...201425056906
draft genome sequence of a new shigella flexneri subserotype, 4s bj10610.shigella flexneri is of great concern in the prevalence of shigellosis and resistance to many antibiotics in developing countries. here, we report the draft genome sequence of a new s. flexneri subserotype, 4s bj10610, isolated from the stool specimens of a patient in beijing, china.201425035336
fluoroquinolone resistance mechanisms of shigella flexneri isolated in bangladesh.to investigate the prevalence and mechanisms of fluoroquinolone resistance in shigella species isolated in bangladesh and to compare with similar strains isolated in china.201425028972
middle-down mass spectrometry enables characterization of branched ubiquitin chains.protein ubiquitylation, one of the most prevalent post-translational modifications in eukaryotes, is involved in regulating nearly every cellular signaling pathway. the vast functional range of ubiquitylation has largely been attributed to the formation of a diverse array of polymeric ubiquitin (polyub) chains. methods that enable the characterization of these diverse chains are necessary to fully understand how differences in structure relate to function. here, we describe a method for the dete ...201425023374
transfer patterns of integron-associated and antibiotic resistance genes in s. flexneri during different time intervals in tianjin, china.shigella is one of the common genera of pathogens responsible for bacterial diarrhoea in humans. according to world health organisation (who), 800,000-1,700,000 patients in china were infected with shigella spp. in 2000, and shigella flexneri is the most common serotype (86%).201425008817
structural basis for lipopolysaccharide insertion in the bacterial outer membrane.one of the fundamental properties of biological membranes is the asymmetric distribution of membrane lipids. in gram-negative bacteria, the outer leaflet of the outer membrane is composed predominantly of lipopolysaccharides (lps). the export of lps requires seven essential lipopolysaccharide transport (lpt) proteins to move lps from the inner membrane, through the periplasm to the surface. of the seven lpt proteins, the lptd-lpte complex is responsible for inserting lps into the external leafle ...201424990751
myosin iia is essential for shigella flexneri cell-to-cell spread.a key feature of shigella pathogenesis is the ability to spread from cell-to-cell post-invasion. this is dependent on the bacteria's ability to initiate de novo f-actin tail polymerisation, followed by protrusion formation, uptake of bacteria-containing protrusion and finally, lysis of the double membrane vacuole in the adjacent cell. in epithelial cells, cytoskeletal tension is maintained by the actin-myosin ii networks. in this study, the role of myosin ii and its specific kinase, myosin light ...201424989342
shigella reroutes host cell central metabolism to obtain high-flux nutrient supply for vigorous intracellular growth.shigella flexneri proliferate in infected human epithelial cells at exceptionally high rates. this vigorous growth has important consequences for rapid progression to life-threatening bloody diarrhea, but the underlying metabolic mechanisms remain poorly understood. here, we used metabolomics, proteomics, and genetic experiments to determine host and shigella metabolism during infection in a cell culture model. the data suggest that infected host cells maintain largely normal fluxes through glyc ...201424958876
reconstituted human polyclonal plasma-derived secretory-like igm and iga maintain the barrier function of epithelial cells infected with an enteropathogen.intravenous administration of polyclonal and monoclonal antibodies has proven to be a clinically valid approach in the treatment, or at least relief, of many acute and chronic pathologies, such as infection, immunodeficiency, and a broad range of autoimmune conditions. plasma-derived igg or recombinant igg are most frequently used for intravenous or subcutaneous administration, whereas a few igm-based products are available as well. we have established recently that secretory-like iga and igm ca ...201424951593
atypical haemolytic uraemic syndrome associated with a cd46 mutation triggered by shigella flexneri.we present a case of haemolytic uraemic syndrome (hus) triggered by shigella flexneri. of the shigella species, only s. dysenteriae type 1 is said to produce shiga toxin and consequently cause hus. investigation of the complement system in this patient revealed a cd46 mutation. in individuals with mutations in complement genes incomplete penetrance of atypical hus (ahus) is seen, suggesting that a trigger, such as infection, is required for disease to manifest. in an era of complement modulatory ...201424944786
elongation factor p and modifying enzyme poxa are necessary for virulence of shigella flexneri.elongation factor p (ef-p) is a universally conserved bacterial translation factor. in many bacteria, ef-p is posttranslationally modified by poxa, which covalently attaches a β-lysine to a conserved lysine residue of ef-p. here we show that both ef-p and poxa are necessary for virulence of the human diarrheal pathogen shigella flexneri. loss of either ef-p or poxa leads to an impaired ability of s. flexneri to invade epithelial cells and form plaques in an epithelial cell monolayer. proteomic a ...201424935977
outer membrane protein a (ompa) of shigella flexneri 2a induces tlr2-mediated activation of b cells: involvement of protein tyrosine kinase, erk and nf-κb.b cells are critically important in combating bacterial infections and their differentiation into plasma cells and memory cells aids bacterial clearance and long-lasting immunity conferred by essentially all vaccines. outer membrane protein a (ompa) of shigella flexneri 2a has been demonstrated to induce the production of igg and iga in vivo following immunization of mice through intranasal route, but the direct involvement of b cells in ompa-mediated immune regulation was not determined. conseq ...201425286253
high-resolution structure of the shigella type-iii secretion needle by solid-state nmr and cryo-electron microscopy.we introduce a general hybrid approach for determining the structures of supramolecular assemblies. cryo-electron microscopy (cryo-em) data define the overall envelope of the assembly and rigid-body orientation of the subunits while solid-state nuclear magnetic resonance (ssnmr) chemical shifts and distance constraints define the local secondary structure, protein fold and inter-subunit interactions. finally, rosetta structure calculations provide a general framework to integrate the different s ...201425264107
[shigella flexneri bacteremia, one adult case and review of the literature]. 201425229381
use of shigella flexneri to study autophagy-cytoskeleton interactions.shigella flexneri is an intracellular pathogen that can escape from phagosomes to reach the cytosol, and polymerize the host actin cytoskeleton to promote its motility and dissemination. new work has shown that proteins involved in actin-based motility are also linked to autophagy, an intracellular degradation process crucial for cell autonomous immunity. strikingly, host cells may prevent actin-based motility of s. flexneri by compartmentalizing bacteria inside 'septin cages' and targeting them ...201425226510
an optofluidic imaging system to measure the biophysical signature of single waterborne bacteria.in this paper, for the first time, an on-chip optofluidic imaging system is innovated to measure the biophysical signatures of single waterborne bacteria, including both their refractive indices and morphologies (size and shape), based on immersion refractometry. the key features of the proposed optofluidic imaging platform include (1) multiple sites for single-bacterium trapping, which enable parallel measurements to achieve higher throughput, and (2) a chaotic micromixer, which enables efficie ...201425205636
time-resolved assembly of a nucleoprotein complex between shigella flexneri virf promoter and its transcriptional repressor h-ns.the virf gene of shigella, responsible for triggering the virulence cascade in this pathogenic bacterium, is transcriptionally repressed by the nucleoid-associated protein h-ns. the primary binding sites of h-ns within the promoter region of virf have been detected here by footprinting experiments in the presence of h-ns or its monomeric dna-binding domain (h-nsctd), which displays the same specificity as intact h-ns. of the 14 short dna fragments identified, 10 overlap sequences similar to the ...201425389261
genome assembly of shigella flexneri atcc 12022, a quality control reference strain.shigella flexneri causes shigellosis, severe and potentially life-threatening diarrhea, and accounts for 18% of shigellosis cases in the united states. here, we present the 4.51-mbp genome assembly of s. flexneri atcc 12022, a quality control and reference strain, in 10 scaffolds.201425359907
genetic and structural identification of an o-acyltransferase gene (oacc) responsible for the 3/4-o-acetylation on rhamnose iii in shigella flexneri serotype 6.o-antigen (o-polysaccharide) of the lipopolysaccharide is a highly variable cell component of the outer membrane in shigella flexneri. it defines the serospecificity and plays an important role in the pathogenesis of shigellosis. there are two distinct o-antigen forms for the 19 serotypes of s. flexneri: one for serotypes 1-5, x, y, 7 (and their subtypes), and the other for serotype 6. although having different basal o-polysaccharide structures, the two forms share a common disaccharide fragment ...201425327486
structural characterization of a flexible two-domain protein in solution using small angle x-ray scattering and nmr data.multidomain proteins in which individual domains are connected by linkers often possess inherent interdomain flexibility that significantly complicates their structural characterization in solution using either nuclear magnetic resonance (nmr) spectroscopy or small-angle x-ray scattering (saxs) alone. here, we report a protocol for joint refinement of flexible multidomain protein structures against nmr distance and angular restraints, residual dipolar couplings, and saxs data. the protocol is ba ...201425456817
comparative proteomic analysis of outer membrane vesicles from shigella flexneri under different culture conditions.the production of outer membrane vesicles (omvs) is a common and regulated process of gram-negative bacteria. nonetheless, the processes of shigella flexneri omv production still remain unclear. s. flexneri is the causative agent of endemic shigellosis in developing countries. the congo red binding of strains is associated with increased infectivity of s. flexneri. therefore, understanding the modulation pattern of omv protein expression induced by congo red will help to elucidate the bacterial ...201425445584
the extant world war 1 dysentery bacillus nctc1: a genomic analysis.shigellosis (previously bacillary dysentery) was the primary diarrhoeal disease of world war 1, but outbreaks still occur in military operations, and shigellosis causes hundreds of thousands of deaths per year in developing nations. we aimed to generate a high-quality reference genome of the historical shigella flexneri isolate nctc1 and to examine the isolate for resistance to antimicrobials.201425441199
targeting of chromatin readers: a novel strategy used by the shigella flexneri virulence effector ospf to reprogram transcription.shigella flexneri, a gram-negative bacterium responsible of bacillary dysentery, uses multiple strategies to overcome host immune defense. we have decrypted how this bacterium manipulates host-cell chromatin binders to take control of immune gene expression. we found that ospf, an injected virulence factor previously identified as a repressor of immune gene expression, targets the chromatin reader hp1γ. heterochromatin protein 1 family members specifically recognize and bind histone h3 methylate ...201428357260
a large outbreak of shigellosis commencing in an internally displaced population, papua new guinea, 2013.the objective of this study was to investigate a large outbreak of shigellosis in papua new guinea that began in a camp for internally displaced persons before spreading throughout the general community.201425648967
shigella flexneri: a three-year antimicrobial resistance monitoring of isolates in a children hospital, ahvaz, iran.shigellosis is an acute gastroenteritis that is one of the most common causes of morbidity and mortality in children with diarrhea in developing countries. the purpose of this study was to describe the distribution of shigella serogroups and serotypes and their antibacterial drug resistance profiles.201425802704
clinical and microbiological profiles of shigellosis in children.shigellosis presents with varied clinical features are dictated by the species involved, virulence factors of the strain, and the host immune status. we studied the species, virulence genes, and antibiotic susceptibility pattern of the shigella strains isolated from 33 children aged less than 12 years, with clinical features of shigellosis. identification and antibiotic sensitivity of shigella species were done using disc diffusion and e-test. multiplex pcr was done for the detection of virulenc ...201425895190
shigella: a highly virulent and elusive pathogen.despite a significant decrease in shigella-related mortality, shigellosis continues to carry a significant burden of disease worldwide, particularly in asia and africa. shigella is a highly virulent pathogen comprised of four major species with numerous subtypes. shigella dysenteriae and shigella flexneri infections are predominant in resource-limited settings. clinical presentations range from mild watery diarrhea to severe dysentery with systemic complications such as electrolyte imbalance, se ...201425110633
molecular characterization of serologically atypical provisional serovars of shigella isolates from kolkata, india.during 2000-2004, 13 shigella strains that were untypable by commercially available antisera were isolated from children <5 years of age with acute diarrhoea in kolkata. these strains were subsequently identified as shigella dysenteriae provisional serovar 204/96 (n = 3), shigella dysenteriae provisional serovar e23507 (n = 1), shigella dysenteriae provisional serovar i9809-73 (n = 1), shigella dysenteriae provisional serovar 93-119 (n = 1), shigella flexneri provisional serovar 88-893 (n = 6) a ...201425261061
[stability of changed properties of streptomycin-resistant strain of shigella flexneri after prolonged preservation]. 201424544446
convergent evolution in the assembly of polyubiquitin degradation signals by the shigella flexneri ipah9.8 ligase.the human pathogen shigella flexneri subverts host function and defenses by deploying a cohort of effector proteins via a type iii secretion system. the ipah family of 10 such effectors mimics ubiquitin ligases but bears no sequence or structural homology to their eukaryotic counterpoints. using rates of (125)i-polyubiquitin chain formation as a functional read out, ipah9.8 displays v-type positive cooperativity with respect to varying concentrations of its ubc5b∼(125)i-ubiquitin thioester co-su ...201425342744
a gene knock-in method used to purify plasmid pspi12 from salmonella enterica serovar pullorum and characterization of ipaj.a small plasmid with 4080 bp long, designated pspi12, was purified from salmonella enterica serovar pullorum using a gene knock-in method by inserting a kanamycin resistance cassette in the plasmid. the g+c content of the plasmid was 51.8%, which is in the range of salmonella genomic dna. a sequence analysis revealed that pspi12 had 99.1% homology to psfd10, which was first reported in the vaccine strain s. enterica serovar chloreaesuis c500, but not prevalent among other strains of s. chloreaes ...201424468333
isolation and molecular characterization of salmonella enterica, escherichia coli o157:h7 and shigella spp. from meat and dairy products in egypt.foodborne pathogens are a major threat to food safety, especially in developing countries where hygiene and sanitation facilities are often poor. salmonella enterica, escherichia coli o157:h7 and shigella spp. are among the major causes of outbreaks of foodborne diseases. this large-scale study investigated the prevalence of these foodborne pathogens in meat (beef and chicken) and dairy products collected from street vendors, butchers, retail markets and slaughterhouses in egypt. a total of 1600 ...201424239976
enhanced antibacterial and anti-biofilm activities of silver nanoparticles against gram-negative and gram-positive bacteria.silver nanoparticles (agnps) have been used as antibacterial, antifungal, antiviral, anti-inflammtory, and antiangiogenic due to its unique properties such as physical, chemical, and biological properties. the present study was aimed to investigate antibacterial and anti-biofilm activities of silver nanoparticles alone and in combination with conventional antibiotics against various human pathogenic bacteria. here, we show that a simple, reliable, cost effective and green method for the synthesi ...201425136281
murine solid tumours as a novel model to study bacterial biofilm formation in vivo.bacteria of many species are able to invade and colonize solid tumours in mice. we have focused on salmonella enterica serovar typhimurium. detailed analysis revealed that such tumour-invading salmonella form biofilms, thus providing a versatile in vivo test system for studying bacterial phenotypes and host-pathogen interactions. it appears that biofilm formation by s. typhimurium is induced as a defence against the immune system of the host, and in particular against neutrophils. further, we ex ...201424724621
electron tomography and simulation of baculovirus actin comet tails support a tethered filament model of pathogen propulsion.several pathogens induce propulsive actin comet tails in cells they invade to disseminate their infection. they achieve this by recruiting factors for actin nucleation, the arp2/3 complex, and polymerization regulators from the host cytoplasm. owing to limited information on the structural organization of actin comets and in particular the spatial arrangement of filaments engaged in propulsion, the underlying mechanism of pathogen movement is currently speculative and controversial. using electr ...201424453943
hpv16l1-attenuated shigella recombinant vaccine induced strong vaginal and systemic immune responses in guinea pig model.though human papillomavirus (hpv) vaccines based on l1 virus-like particles (vlps) have excellent protective effect against hpv-induced cervical cancer, they are too expensive to be afforded by the developing countries, where most cases of cervical cancer occur. a live bacterial-based vaccine could be an inexpensive alternative. the aim of this study was to evaluate the potential value of live attenuated shigella. flexneri 2a sc602 strain-based hpv16l1 as a high-efficiency, low-cost hpv16l1 muco ...201425483698
age-dependent association among helicobacter pylori infection, serum pepsinogen levels and immune response of children to live oral cholera vaccine cvd 103-hgr.through its effects on gastric secretion, we hypothesized that helicobacter pylori infection may influence oral immunization. accordingly, we examined the association between h. pylori infection, serum pepsinogen (pg) (measures for h. pylori gastritis) and vibriocidal antibody (a correlate of protection) seroconversion following oral immunization with cvd 103-hgr live cholera vaccine among children of different ages.201424454714
plantaricin ld1: a bacteriocin produced by food isolate of lactobacillus plantarum ld1.plantaricin ld1, a bacteriocin produced by lactobacillus plantarum ld1, was characterized for biochemical and antimicrobial properties. bacteriocin showed stability at high temperatures (100 °c for 20 min and 121 °c for 15 min under 15 psi pressure), in a ph range of 2.0-8.0 and also in the presence of organic solvents, surfactants and detergents. the crude preparation was not affected by catalase, amylase and lipase but activity was reduced in the presence of pepsin, trypsin and proteinase k sh ...201424522411
probiotic assessment of enterococcus durans 6hl and lactococcus lactis 2hl isolated from vaginal microflora.forty-five lactic acid bacteria (lab) were isolated from the vaginal specimens of healthy fertile women, and the identities of the bacteria were confirmed by sequencing of their 16s rdna genes. among these bacteria, only four isolates were able to resist and survive in low ph, bile salts and simulated in vitro digestion conditions. lactococcus lactis 2hl, enterococcus durans 6hl, lactobacillus acidophilus 36yl and lactobacillus plantarum 5bl showed the best resistance to these conditions. these ...201424913559
stress tolerant virulent strains of cronobacter sakazakii from food.cronobacter sakazakii is considered as an emerging foodborne pathogen. the aim of this study was to isolate and characterize virulent strains of cronobacter sakazakii from food samples of bangladesh.201425723712
quantification of polyphenols and evaluation of antimicrobial, analgesic and anti-inflammatory activities of aqueous and acetone-water extracts of libidibia ferrea, parapiptadenia rigida and psidium guajava.vast numbers of plant species from northeastern brazil have not yet been phytochemically or biologically evaluated.201425124277
analysis on the interaction domain of virg and apyrase by pull-down assay.virg is outer membrane protein of shigella and affects the spread of shigella. recently it has been reported that apyrase influences the location of virg, although the underlying mechanism remains poorly understood. the site of interaction between apyrase and virg is the focus of our research. first we constructed recombinant plasmid phis-phon2 and ps-(v1-1102, v53-758, v759-1102, v53-319, v320-507, v507-758) by denaturation-renaturation, the phon2:kan mutant of shigella flexneri 5a m90t by a mo ...201425379645
a shigella flexneri virulence plasmid encoded factor controls production of outer membrane vesicles.shigella spp. use a repertoire of virulence plasmid-encoded factors to cause shigellosis. these include components of a type iii secretion apparatus (t3sa) that is required for invasion of epithelial cells and many genes of unknown function. we constructed an array of 99 deletion mutants comprising all genes encoded by the virulence plasmid (excluding those known to be required for plasmid maintenance) of shigella flexneri. we screened these mutants for their ability to bind the dye congo red: a ...201425378474
clinical isolates of shiga toxin 1a-producing shigella flexneri with an epidemiological link to recent travel to hispañiola.shiga toxins (stx) are cytotoxins involved in severe human intestinal disease. these toxins are commonly found in shigella dysenteriae serotype 1 and shiga-toxin-producing escherichia coli; however, the toxin genes have been found in other shigella species. we identified 26 shigella flexneri serotype 2 strains isolated by public health laboratories in the united states during 2001-2013, which encode the shiga toxin 1a gene (stx1a). these strains produced and released stx1a as measured by cytotox ...201425271406
evaluation of the ability of four esbl-screening media to detect esbl-producing salmonella and shigella.the aim of this study was to compare the ability of four commercially available media for screening extended-spectrum beta-lactamase (esbl) to detect and identify esbl-producing salmonella and shigella in fecal samples. a total of 71 salmonella- and 21 shigella-isolates producing esbl(a) and/or ampc, were received at norwegian institute of public health between 2005 and 2012. the 92 isolates were mixed with fecal specimens and tested on four esbl screening media; chromid esbl (biomèrieux), brill ...201425204319
proteomes of pathogenic escherichia coli/shigella group surveyed in their host environments.proteomic studies on shigella dysenteriae, shigella flexneri, enterohemorrhagic escherichia coli and uropathogenic e. coli (upec) are reviewed. upec causes infections in the urogenital tract, whereas the other species colonize and, to varying degrees, invade the intestinal tract. type iii secretion systems used to breach the mucosal barrier by the intestinal pathogens revealed distinct expression patterns in different host environments. dynamic adaptations to changes in nutrient availability and ...201425163594
the immune response of two microbial antigens delivered intradermally, sublingually, or the combination thereof.a key consideration to produce a successful vaccine is the choice of appropriate vaccination route. though most vaccines are administered parenterally, this route is not effective in producing a robust mucosal or cell-mediated response. intradermal and sublingual vaccinations have been explored recently as potential needle-free immunization strategies. we explored intradermal and sublingual routes as well as the combination of the two routes in eliciting both systemic and mucosal immune response ...201425111827
[preparation and identification of the polyclonal antibody against gapdh protein from shigella flexneri m90t].to prepare mouse polyclonal antibodies against shigella flexneri m90t glyceraldehyde-3-phosphate dehydrogenase (gapdh), and verify its titer and specificity.201424721410
probiotic potential of lactobacillus plantarum ld1 isolated from batter of dosa, a south indian fermented food.lactobacillus plantarum ld1 was isolated from dosa batter and identified by biochemical, physiological and genetic methods. species level identification was done by 16s rdna amplification and sequencing. the probiotic potential of strain ld1 was assessed by different standard parameters. cell surface hydrophobicity was recorded to be 62% with sat value <0.007 m. seventy-eight percent of viable count was found after treatment with simulated gastric juice containing pepsin (ph 2.0). bile salt tole ...201424676724
rabbit monoclonal antibodies directed at the t3ss effector protein yopm identify human pathogenic yersinia isolates.the yersinia outer protein m (yopm) is a type 3 secretion system (t3ss)-dependent effector protein of yersinia enterocolitica, yersinia pseudotuberculosis and yersinia pestis. although yopm is indispensable for full virulence, its molecular functions still remain largely elusive. recently, we could identify the recombinant yopm (ryopm) protein derived from the y. enterocolitica strain 8081 (jb580) as a cell-penetrating protein, which down-regulates the expression of various pro-inflammatory cyto ...201424636859
intradermal delivery of shigella ipab and ipad type iii secretion proteins: kinetics of cell recruitment and antigen uptake, mucosal and systemic immunity, and protection across serotypes.shigella is one of the leading pathogens contributing to the vast pediatric diarrheal disease burden in low-income countries. no licensed vaccine is available, and the existing candidates are only partially effective and serotype specific. shigella type iii secretion system proteins ipab and ipad, which are conserved across shigella spp., are candidates for a broadly protective, subunit-based vaccine. in this study, we investigated the immunogenicity and protective efficacy of ipab and ipad admi ...201424453241
relationship between o-antigen chain length and resistance to colicin e2 in shigella flexneri.the shigella flexneri polysaccharide co-polymerase class 1a (pcp1a) protein, wzzbsf, regulates lps o-antigen (oag) chain length to confer short (s)-type oag chains of ~10-17 oag repeat units (rus). the s-type oag chains affect shigella flexneri virulence as they influence icsa-mediated actin-based motility. however, they do not confer resistance to complement; this is conferred by the very-long (vl)-type oag chains determined by wzzb(phs2). colicins are bacterial proteins produced by some escher ...201424425769
¹³c, ¹⁵n and ¹h backbone and side chain chemical shift assignment of acid-stress bacterial chaperone hdea at ph 6.hdea is a small chaperone found in the periplasm of several common pathogenic bacteria (escherichia coli, shigella flexneri and brucella abortus) which are the leading causes of dysentery worldwide, especially in developing countries. its job is to protect other periplasmic proteins from aggregating as the bacteria pass through the low ph environment of the human stomach on their way to infect the intestines. hdea is an inactive folded dimer at neutral ph, but becomes a disordered active monomer ...201423835624
profile of volatile components of hydrodistilled and extracted leaves of jacaranda acutifolia and their antimicrobial activity against foodborne pathogens.volatile constituents of the essential oil and n-hexane extract of jacaranda acutifolia humb. and bonpl. (bignoniaceae) leaves were determined, and their antimicrobial activities were investigated using an agar diffusion method. the minimum inhibitory concentrations (mic) were determined and compared with those of standard antibiotics (penicillin, gentamicin and nystatin). the chemical composition of the oils was analyzed by capillary gas chromatography (glc-fid) and gas chromatography-mass spec ...201425230515
cold-active antibacterial and antifungal activities and antibiotic resistance of bacteria isolated from an alpine hydrocarbon-contaminated industrial site.selection pressure in hydrocarbon-contaminated soils may lead not only to increased microbial resistance to antibiotics, but also to increased capacity of the soil indigenous population to produce antimicrobial compounds. therefore, we studied the antibiotic resistance pattern and antibacterial and/or antifungal activities of 47 bacterial strains isolated from an industrial alpine site heavily polluted with petroleum hydrocarbons. resistance to penicillin was more widespread (49%) than resistanc ...201424880083
synthesis, structures, spectroscopy and antimicrobial properties of complexes of copper(ii) with salicylaldehyde n-substituted thiosemicarbazones and 2,2'-bipyridine or 1,10-phenanthroline.among the biometals (cu, co, ni-cofactors in many enzymes), copper derivatives of o, n, s-donor salicylaldehyde thiosemicarbazones have received considerable attention owing to their potential biological applications. eight new complexes of salicylaldehyde-n-substituted thiosemicarbazones [5-meo-2-ho-c₆h₄-c(2)(h)n(3)-n(2)h-c(1)(s)-n(1)hr; r = me, h2l(1); et, h₂l(1), ph, h₂l(3), h, h₂l(4)] with copper(ii), namely, [cu(κ(3)-o,n,s-l)( κ(2)-n,n-l')] {(l)(2-) = (l(1))(2-), l' = bipy, 1, phen, 2; (l)( ...201424583354
synthesis, structural characterization, and evaluation of the biological properties of heteroleptic palladium(ii) complexes.five heteroleptic palladium(ii) complexes of the general formula pd(pr3)(tu)cl2, where pr3 = triphenylphosphine (1), diphenyl-o-tolylphosphine (2), diphenyl-p-tolylphosphine (3), diphenyl-t-butylphosphine (4), and diphenyl-o-methoxyphenylphosphine (5), and tu = 1,3-bis(2-methoxyphenyl) thiourea. they all have been synthesized and characterized by various spectroscopic techniques (elemental analysis, ftir, and (1)h nmr and the ligand 1,3-bis(2-methoxyphenyl) thiourea was synthesized by single cry ...201425276113
detection of salmonella spp. by a loop-mediated isothermal amplification (lamp) method targeting bcfd gene.in this study, we developed and validated a loop-mediated isothermal amplification (lamp) assay for salmonella detection targeting bcfd gene, a conserved fimbrial operon gene existing in salmonella. the salmonella lamp assay we developed successfully amplified 44 salmonella strains (14 standard strains and 30 clinical isolates), but none of 9 non-salmonella standard strains (proteus mirabilis, listeria monocytogenes, escherichia coli, pseudomonas aeruginosa, shigella flexneri, shigella sonnei, k ...201425199410
decay of genetic markers for fecal bacterial indicators and pathogens in sand from lake superior.beach sands impact water quality and pathogen loads, however, the comparative decay of the fecal indicator bacteria (fib) enterococcus spp. and escherichia coli, and pathogens in freshwater sand have not been examined. in this study, freshwater sand microcosms were inoculated with sewage and pure cultures of bacterial pathogens to compare relative decay rates. the abundance of culturable enterococcus spp. and e. coli, genetic markers for enterococcus spp. (entero1), total bacteroides (allbac), a ...201424793108
phyllanthus wightianus müll. arg.: a potential source for natural antimicrobial agents.phyllanthus wightianus belongs to euphorbiaceae family having ethnobotanical importance. the present study deals with validating the antimicrobial potential of solvent leaf extracts of p. wightianus. 11 human bacterial pathogens (bacillus subtilis, streptococcus pneumoniae, staphylococcus epidermidis, proteus vulgaris, pseudomonas aeruginosa, klebsiella pneumoniae, salmonella typhimurium, escherichia coli, shigella flexneri, proteus vulgaris, and serratia marcescens) and 4 fungal pathogens (cand ...201424883301
cgtase-catalysed cis-glucosylation of l-rhamnosides for the preparation of shigella flexneri 2a and 3a haptens.we report the enzymatic synthesis of α-d-glucopyranosyl-(1→4)-α-l-rhamnopyranoside and α-d-glucopyranosyl-(1→3)-α-l-rhamnopyranoside by using a wild-type transglucosidase in combination with glucoamylase and glucose oxidase. it was shown that bacillus circulans 251 cyclodextrin glucanotransferase (cgtase, ec 2.1.4.19) can efficiently couple an α-l-rhamnosyl acceptor to a maltodextrin molecule with an α-(1→4) linkage, albeit in mixture with the α-(1→3) regioisomer, thus giving two glucosylated ac ...201424376024
biosynthesis of silver nanoparticles using acacia leucophloea extract and their antibacterial activity.the immense potential of nanobiotechnology makes it an intensely researched field in modern medicine. green nanomaterial synthesis techniques for medicinal applications are desired because of their biocompatibility and lack of toxic byproducts. we report the toxic byproducts free phytosynthesis of stable silver nanoparticles (agnps) using the bark extract of the traditional medicinal plant acacia leucophloea (fabaceae). visual observation, ultraviolet-visible spectroscopy, and transmission elect ...201424876776
metal-based carboxamide-derived compounds endowed with antibacterial and antifungal activity.a series of three bioactive thiourea (carboxamide) derivatives, n-(dipropylcarbamothioyl)-thiophene-2-carboxamide (l(1)), n-(dipropylcarbamothioyl)-5-methylthiophene-2-carboxamide (l(2)) and 5-bromo-n-(dipropylcarbamothioyl)furan-2-carboxamide (l(3)) and their cobalt(ii), copper(ii), nickel(ii) and zinc(ii) complexes (1)-(12) have been synthesized and characterized by their ir,(1)h-nmr spectroscopy, mass spectrometry and elemental analysis data. the crystal structure of one of the ligand, n-(dip ...201423914928
impact of reclaimed water irrigation on antibiotic resistance in public parks, beijing, china.the abundance and distribution of antibiotics and antibiotic resistance genes (args) in soils from six parks using reclaimed water in beijing, china, were characterized. three classes of commonly used antibiotics (tetracycles, quinolones, and sulfonamides) were analyzed by liquid chromatography-tandem mass spectrometry (lc-ms/ms). the highest concentrations of tetracyclines and quinolones were 145.2 μg kg(-1) and 79.2 μg kg(-1), respectively. detected tetg, tetw, suli, and sulii genes were quant ...201424071635
modulation of endotoxicity of shigella generalized modules for membrane antigens (gmma) by genetic lipid a modifications: relative activation of tlr4 and tlr2 pathways in different mutants.outer membrane particles from gram-negative bacteria are attractive vaccine candidates as they present surface antigens in their natural context. we previously developed a high yield production process for genetically derived particles, called generalized modules for membrane antigens (gmma), from shigella. as gmma are derived from the outer membrane, they contain immunostimulatory components, especially lipopolysaccharide (lps). we examined ways of reducing their reactogenicity by modifying lip ...201425023285
aerobic bacterial community of american cockroach periplaneta americana,a step toward finding suitable paratransgenesis candidates.cockroaches mechanically spread pathogenic agents, however, little is known about their gut microbiota. identification of midgut microbial community helps targeting novel biological control strategies such as paratransgenesis. here the bacterial microbiota of periplaneta americana midgut, were identified and evaluated for finding proper paratransgenesis candidate.201426114142
widespread antibiotic resistance of diarrheagenic escherichia coli and shigella species.antibiotic resistance of enteric pathogens particularly shigella species, is a critical world-wide problem and monitoring their resistant pattern is essential, because the choice of antibiotics is absolutely dependent on regional antibiotic susceptibility patterns. during summer 2013, an unusual increase in number of diarrheal diseases was noticed in isfahan, a central province of iran. therefore, the antibiotic resistance of diarrheagenic escherichia coli and shigella species isolated were eval ...201425002896
polar localization of phon2, a periplasmic virulence-associated factor of shigella flexneri, is required for proper icsa exposition at the old bacterial pole.proper protein localization is critical for bacterial virulence. phon2 is a virulence-associated atp-diphosphohydrolase (apyrase) involved in icsa-mediated actin-based motility of s. flexneri. herein, by analyzing a δphon2 mutant of the s. flexneri strain m90t and by generating phon2::ha fusions, we show that phon2, is a periplasmic protein that strictly localizes at the bacterial poles, with a strong preference for the old pole, the pole where icsa is exposed, and that it is required for proper ...201424587292
serotype-converting bacteriophage sfii encodes an acyltransferase protein that mediates 6-o-acetylation of glcnac in shigella flexneri o-antigens, conferring on the host a novel o-antigen epitope.shigella flexneri o-antigen is an important and highly variable cell component presented on the outer leaflet of the outer membrane. most shigella flexneri bacteria share an o-antigen backbone composed of →2)-α-l-rhap(iii)-(1→2)-α-l-rhap(ii)-(1→3)-α-l-rhap(i)-(1→3)-β-d-glcpnac-(1→ repeats, which can be modified by adding various chemical groups to different sugars, giving rise to diverse o-antigen structures and, correspondingly, to various serotypes. the known modifications include glucosylatio ...201425112477
[myotonic retinopathy]. 20144539596
[myotonic retinopathy]. 20144539596
kinematics of the chest wall during speech production: volume displacements of the rib cage, abdomen, and lung. 20144267384
the electroencephalogram in clinical practice. 20144239108
the nature of disability. 20144229260
saline abortion. 20144276841
presence of accessory pulp canals. 20144514051
medicine and public affairs. from the tapes: mr. nixon on cholesterol, insomnia, etc. 20144215024
apomorphine, pimozide, l-dopa and the probenecid test in huntington's chorea. 20144267059
apomorphine, pimozide, l-dopa and the probenecid test in huntington's chorea. 20144267059
the liquor amnii bilirubin-protein ratio in the management of rhesus isoimmunization. 20144214983
[anesthesia in patients with diabetes]. 20144650564
[anesthesia in patients with diabetes]. 20144650564
[antigenic action of cartilage. 3. cartilage cells and basic substance and their antigenic action]. 20144251803
different ratios of the ldd and ddd diastereoisomers of phytanic acid in patients with refsum's disease. 20144176022
[coagulation disorders after reinjection of concentrated ascitic fluid. preliminary study]. 20144275793
a colloid osmometer for small fluid samples. 20144823020
[value of iodine determination by neutron activation in thyroid testing in children]. 20144159516
skeletal muscle function and sustained swimming speeds in the coalfish gadus virens l. 20144145765
significance of hyperamylasaemia and abdominal pain in diabetic ketoacidosis.an analysis of 35 consecutive episodes of diabetic ketoacidosis confirmed the frequent high levels of serum amylase in this condition. serum amylase was raised during 21 episodes (60%), and in six instances (17%) the peak level exceeded 1,000 somogyi units per 100 ml. hyperamylasaemia was more often found when the initial blood sugar exceeded 500 mg/100 ml, or when the onset of the episode had been relatively acute (less than 48 hours). there was no conclusive evidence in any patient to support ...20144198367
[the clinical picture of adenovirus infections--a contribution to the problem]. 20144287686
[the clinical picture of adenovirus infections--a contribution to the problem]. 20144287686
[bilateral hypoplasia of the internal carotid arteries. apropos of an anatomo-clinical case]. 20144367937
[experiences with lumbosacral manipulation therapy in an industrial polyclinic]. 20144236580
cricopharyngeal achalasia in childhood. 20144471680
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