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isolation and characterization of lactic acid bacteria from traditional pickles of himachal pradesh, india.a total of 15 isolates of lactic acid bacteria (lab) were isolated from traditional pickles of rural and urban areas of himachal pradesh. these isolates were identified as enterococcus faecalis (7), lactobacillus plantarum (3), pediococcus pentosaceus (2), leuconostoc mesenteroides (1), lactococcus lactis (1) and enterococcus sp. (1) on the basis of morphological, biochemical and 16s rdna sequence analysis. all the labs produced exopolysaccharides, have antibiotic susceptibility, and possess act ...201728720951
detection of eight foodborne bacterial pathogens by oligonucleotide array hybridization.simultaneous and rapid detection of multiple foodborne bacterial pathogens is important for the prevention of foodborne illnesses.201728713514
characterization of a large antibiotic resistance plasmid found in enteropathogenic escherichia coli strain b171 and its relatedness to plasmids of diverse e. coli and shigella strains.enteropathogenic escherichia coli (epec) is a leading cause of severe infantile diarrhea in developing countries. previous research has focused on the diversity of the epec virulence plasmid, whereas less is known regarding the genetic content and distribution of antibiotic resistance plasmids carried by epec. a previous study demonstrated that in addition to the virulence plasmid, reference epec strain b171 harbors a second, larger plasmid that confers antibiotic resistance. to further understa ...201728674052
dissecting binding of a β-barrel membrane protein by phage display.membrane proteins (mps) constitute a third of all proteomes, and contribute to a myriad of cellular functions including intercellular communication, nutrient transport and energy generation. for example, tonb-dependent transporters (tbdts) in the outer membrane of gram-negative bacteria play an essential role transporting iron and other nutrients into the bacterial cell. the inherently hydrophobic surfaces of mps complicates protein expression, purification, and characterization. thus, dissectin ...201728627567
characterization of hypericum perforatum polysaccharides with antioxidant and antimicrobial activities: optimization based statistical modeling.in this study, the extracting parameters of crude polysaccharides (cpss) from the hypericum perforatum (hp) including extraction time (eti, 60-180min), extraction temperature (ete, 60-90°c), and the water/solid ratio (w/s, 10-30 was optimized by using three-variable-three-level box-behnken design-response surface methodology (bbd-rsm) based on the single-factor experiments. the optimal extraction conditions were as follow: eti 117.5min, ete 74.28°c, and w/s 20.3:1. under these conditions, the ex ...201728602988
protection against shigellosis caused by shigella dysenteriae serotype 4 in guinea pigs using escherichia albertii dm104 as a live vaccine candidate strain.recently, we reported the induction of protective immunity by environmental escherichia albertii strain dm104 against shigella dysenteriae in guinea pig model. in this study, we assessed three different immunization routes, such as intranasal, oral, and intrarectal routes, and revealed differences in immune responses by measuring both the serum igg and mucosal iga antibody titers. protective efficacy of different routes of immunization was also determined by challenging immunized guinea pigs aga ...201728597684
in vitro antibacterial activity of poly (amidoamine)-g7 dendrimer.nano-scale dendrimers are synthetic macromolecules that frequently used in medical and health field. traditional anibiotics are induce bacterial resistence so there is an urgent need for novel antibacterial drug invention. in the present study seventh generation poly (amidoamine) (pamam-g7) dendrimer was synthesized and its antibacterial activities were evaluated against representative gram- negative and gram-positive bacteria.201728583153
evaluation of pigments from methanolic extract of tagetes erecta and beta vulgaris as antioxidant and antibacterial agent.the total phenolic content (tpc), antioxidant and antibacterial activities of methanolic extract of marigold flower (mf) (tagetes erecta) and beet root (br) (beta vulgaris) were examined. the present work reveals that mf contained greater amount of tpc (42.5 mg/g gae) as compared to br (39.4 mg/g gae). methanolic extract of mf exhibited excellent dpph free radical scavenging power (ic50 0.0716 mg/ml) and reducing power at 1 mg/ml concentration. similar results have been obtained in ftc and tba m ...201728494614
shigella dysenteriae infection activates proinflammatory response through β-catenin/nf-κb signaling pathway.shigella dysenteriae (s.dysenteriae) the causative agent of bacillary dysentery invades the human colonic epithelium resulting in severe intestinal inflammatory response and epithelial destruction. however, the mechanism by which s.dysenteriae infection regulates proinflammatory cytokines during intestinal inflammation is still obscure. in this study, we evaluated whether the interaction of β-catenin and nf-κb regulates proinflammatory cytokines tnf-α and il-8 by modulating gsk-3β activity durin ...201728430783
a new phthalide from the endophytic fungus xylaria sp. gdg-102.a new phthalide derivative, xylarphthalide a (1), along with two known compounds (-)-5-carboxylmellein (2) and (-)-5-methylmellein (3), were isolated from the endophytic fungus xylaria sp. gdg-102 cultured from the chinese medicinal plant sophora tonkinensis. their structures were identified by ms and nmr experiments, and the absolute configuration of 1 was further confirmed by single-crystal x-ray diffraction analysis. compound 1-3 showed antibacterial activities against bacillus megaterium, ba ...201728385040
virulotyping of shigella spp. isolated from pediatric patients in tehran, iran.shigellosis is a considerable infectious disease with high morbidity and mortality among children worldwide. in this survey the prevalence of four important virulence genes including ial, ipah, set1a, and set1b were investigated among shigella strains and the related gene profiles identified in the present investigation, stool specimens were collected from children who were referred to two hospitals in tehran, iran. the samples were collected during 3 years (2008-2010) from children who were sus ...201728218003
relationship between drug resistance and the clustered, regularly interspaced, short, palindromic repeat-associated protein genes cas1 and cas2 in shigella from giant panda dung.to detect drug resistance in shigella obtained from the dung of the giant panda, explore the factors leading to drug resistance in shigella, understand the characteristics of clustered, regularly interspaced, short, palindromic repeats (crispr), and assess the relationship between crispr and drug resistance.201728207509
sibling srna ryfa1 influences shigella dysenteriae pathogenesis.small regulatory rnas (srnas) of shigella dysenteriae and other pathogens are vital for the regulation of virulence-associated genes and processes. here, we characterize ryfa1, one member of a sibling pair of srnas produced by s. dysenteriae. unlike its nearly identical sibling molecule, ryfa2, predicted to be encoded almost exclusively by non-pathogenic species, the presence of a gene encoding ryfa1, or a ryfa1-like molecule, is strongly correlated with virulence in a variety of enteropathogens ...201728134784
transcriptional and posttranscriptional regulation of shigella shut in response to host-associated iron availability and temperature.like most bacteria, shigella must maintain a precise balance between the necessity and toxicity of iron; a balance that is achieved, at least in part, by regulating the production of bacterial iron acquisition systems in response to specific environmental signals. using the shigella heme utilization (shu) system, s. dysenteriae is able to acquire iron from heme, a potentially rich source of nutritional iron within the otherwise iron-limited environment of the human host. investigations presented ...201728127899
[point-of-care tests for the rapid diagnosis of shigellosis].worldwide, it is estimated that 140 million people suffer from shigellosis annually. the traditional identification of shigella spp. by culture lacks sensitivity. rapid diagnosis of shigellosis is important because it allows to engage appropriate antimicrobial treatment that shortens the duration and severity of the illness and reduces microbial carriage, thus the spread of infection in the community. onestep immunochromatographic dipstick tests have been successfully developed at institut paste ...201728116567
characterization of two polyvalent phages infecting enterobacteriaceae.bacteriophages display remarkable genetic diversity and host specificity. in this study, we explore phages infecting bacterial strains of the enterobacteriaceae family because of their ability to infect related but distinct hosts. we isolated and characterized two novel virulent phages, sh6 and sh7, using a strain of shigella flexneri as host bacterium. morphological and genomic analyses revealed that phage sh6 belongs to the t1virus genus of the siphoviridae family. conversely, phage sh7 was cl ...201728091598
facile microwave-assisted synthesis of te-doped hydroxyapatite nanorods and nanosheets and their characterizations for bone cement applications.in this work, the authors have fabricated the nanorods and nanosheets of pure and te-doped hap with different te concentrations (0.04, 0.08, 0.16, 0.24wt%) by microwave-assisted technique at low temperature. the crystallite size, degree of crystallinity and lattice parameters are calculated. fe-sem study confirms that the fabricated nanostructures are nanorods of diameter about 10nm in undoped and at low concentration of te doping. however, at and higher concentration, it becomes nanosheets of a ...201728024611
a proteomics assay to detect eight cbrn-relevant toxins in food.a proteomics assay was set up to analyze food substrates for eight toxins of the cbrn (chemical, biological, radiological and nuclear) threat, namely ricin, clostridium perfringens epsilon toxin (etx), staphylococcus aureus enterotoxins (sea, seb and sed), shigatoxins from shigella dysenteriae and entero-hemorragic escherichia coli strains (stx1 and stx2) and campylobacter jejuni cytolethal distending toxin (cdt). the assay developed was based on an antibody-free sample preparation followed by b ...201728008711
aloe vera (aloe barbadensis miller) supplemented probiotic lassi prevents shigella infiltration from epithelial barrier into systemic blood flow in mice model.the aim of present work was to investigate preventive role of orally administered aloe vera supplemented probiotic lassi (apl) on shigella dysenteriae infection in mice. at the end of experimental period (2, 5 and 7 days of challenging), different organs such as spleen, liver, small intestine, large intestine, and peritoneal fluid were collected and assessed for shigella colonization. secretary iga was estimated in intestinal fluid. blood was collected in heparinized tubes for various haematolog ...201727914960
immunization with r-lactococcus lactis expressing outer membrane protein a of shigella dysenteriae type-1: evaluation of oral and intranasal route of administration.to evaluate the comparative immunogenic potential of food grade lactococcus lactis expressing outer membrane protein a (ompa) of shigella dysenteriae type-1 (sd-1) when administered either orally or intranasally.201727860045
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).201627814742
active shiga-like toxin produced by some aeromonas spp., isolated in mexico city.shiga-like toxins (stx) represent a group of bacterial toxins involved in human and animal diseases. stx is produced by enterohemorrhagic escherichia coli, shigella dysenteriae type 1, citrobacter freundii, and aeromonas spp.; stx is an important cause of bloody diarrhea and hemolytic uremic syndrome (hus). the aim of this study was to identify the stx1/stx2 genes in clinical strains and outer membrane vesicles (omvs) of aeromonas spp., 66 strains were isolated from children who live in mexico c ...201627725813
erratum: global phylogeography and evolutionary history of shigella dysenteriae type 1. 201627694821
stable expression of shigella dysenteriae serotype 1 o-antigen genes integrated into the chromosome of live salmonella oral vaccine vector ty21a.typhoid fever and shigellosis cause high morbidity and mortality worldwide, yet no anti-shigella vaccine is currently available. however, to protect against typhoid fever, an approved vaccine, based on the attenuated salmonella enterica serovar typhi strain ty21a is available. we have investigated ty21a as a live oral vaccine vector for expression of heterologous foreign antigens to protect against other diseases (e.g. shigellosis, anthrax, and plague). shigella lps is a potent vaccine antigen f ...201627655911
development of recombinant lactococcus lactis displaying albumin-binding domain variants against shiga toxin 1 b subunit.infections with shiga toxin-producing bacteria, like enterohemorrhagic escherichia coli and shigella dysenteriae, represent a serious medical problem. no specific and effective treatment is available for patients with these infections, creating a need for the development of new therapies. recombinant lactic acid bacterium lactococcus lactis was engineered to bind shiga toxin by displaying novel designed albumin binding domains (abd) against shiga toxin 1 b subunit (stx1b) on their surface. funct ...201627606705
characterization of beauty salon wastewater from kwame nkrumah university of science and technology, kumasi, ghana, and its surrounding communities.due to the increase in students' population over the years, the kwame nkrumah university of science and technology (knust), kumasi, ghana, and its surrounding communities have seen an increase in the number of beauty salons. the assessment of the quality of salon wastewater has received little attention, as a potential source of environmental and public health hazard, due to the lack of literature on this issue. the main aim of this study is to assess wastewater effluent characteristics in knust ...201627594788
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.201627576729
global phylogeography and evolutionary history of shigella dysenteriae type 1.together with plague, smallpox and typhus, epidemics of dysentery have been a major scourge of human populations for centuries(1). a previous genomic study concluded that shigella dysenteriae type 1 (sd1), the epidemic dysentery bacillus, emerged and spread worldwide after the first world war, with no clear pattern of transmission(2). this is not consistent with the massive cyclic dysentery epidemics reported in europe during the eighteenth and nineteenth centuries(1,3,4) and the first isolation ...201627572446
isolation of pathogenic bacteria from hospital staff apparel in nigeria.a survey of bacteria contamination of hospital staff apparel in use in anambra state, nigeria, was carried out to determine the extent of contamination by clinically important bacteria. of a total of 125 swab samples of hospital staff apparel, 72 (58%) showed bacterial contamination including 32 (70%) of 46 samples from hand gloves, 28 of 45 (62%) samples from protective gowns, and 12 of 34 (35%) samples from face-shields. the potentially pathogenic bacteria isolated were salmonella spp, proteus ...200527529000
erratum to: genome sequencing, annotation and comparative genomic analysis of shigella dysenteriae strain sd1d.[this corrects the article doi: 10.1186/1757-4749-6-28.].201627516810
pathogen-associated porin turns il-10 competent b-1a cells toward proinflammatory cytokine response.shigellosis is a major problem in the developing countries causing mortality and morbidity particularly among the children. shigella spp. harbours the epithelial cells of the human colon to infect the host and spread the disease. we analyzed the response of b-1a cells, the major component of the mucosal immune system to porin of shigella dysenteriae type 1. we show that porin while proliferating b-1a cells, deplete siglec-g, the inhibitory molecule present on b-1a cells. adjuvanticity of porin h ...201627498179
occurrence of potential bacterial pathogens and their antimicrobial susceptibility patterns isolated from herbal medicinal products sold in different markets of gondar town, northwest ethiopia.background. the world health organization estimates that about 80% of the world's population uses herbal medicine to treat various illnesses as means of primary healthcare. however, during preparation, herbal plants may be exposed to contamination by potential pathogens, and this may lead to infections. the aim of this study was to determine bacterial contamination of herbal medicinal products and to assess the antibiotic susceptibility pattern of the isolated bacteria. methods. a cross-sectiona ...201627299154
a two-step method for extraction of lipopolysaccharide from shigella dysenteriae serotype 1 and salmonella typhimurium: an improved method for enhanced yield and purity.bacterial lipopolysaccharide (lps) has been widely used as an antigen and adjuvant in immunological applications. amongst the methods developed for extraction of lps, hot phenol extraction (hpe) method is the gold standard. however, the hpe method provides poor yield of lps (~4.5% by weight), is associated with relatively higher impurities of proteins and nucleic acids, and the acidic hot phenol can cause a degradative effect on lps. in this work a two-step extraction (tse) method was developed ...201627208662
competitive survival of escherichia coli, vibrio cholerae, salmonella typhimurium and shigella dysenteriae in riverbed sediments.studies on the survival of bacterial enteric pathogens in riverbed sediments have mostly focused on individual organisms. reports on the competitive survival of these pathogens in riverbed sediments under the same experimental setup are limited. we investigated the survival of escherichia coli, salmonella enterica ser. typhimurium, vibrio cholerae and shigella dysenteriae in riverbed sediments of the apies river. experiments were performed in flow chambers containing three sediment types and con ...201627193001
[microbiological approach to a possible infective endocarditis case caused by aggregatibacter actinomycetemcomitans].aggregatibacter (actinobacillus) actinomycetemcomitans, a small, gram-negative coccobacillus that grows slow and fastidious, is generally colonized in the oral cavity. it is a rarely seen bacterium because of the difficulty of isolation but it can be a causative agent for dental infections and infective endocarditis (ie) particularly in the persons having prosthetic heart valves. in this report, a possible ie case caused by a.actinomycetemcomitans in a patient with aortic valve replacement has b ...201627175505
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 ...201627148494
two novel antimicrobial peptides from skin venoms of spadefoot toad megophrys minor.amphibian skin contains rich bioactive peptides. especially, a large amount of antimicrobial peptides have been identified from amphibian skin secretions. antimicrobial peptides display potent cytolytic activities against a range of pathogenic bacteria and fungi and play important defense roles. no antimicrobial peptides have been reported from toads belonging to the family of pelobatidae. in this work, two novel antimicrobial peptides (megin 1 and megin 2) were purified and characterized from t ...201627114317
screening of furanone in cucurbita melo and evaluation of its bioactive potential using in silico studies.the work presented here attempts to screen for the presence of 4-hydroxy-2,5-dimethyl-3(2h)-furanone in fruits and also any bioactive potential present in the fruit extracts. curcurbita melo was selected for the study, and the fruit was crushed, filtered and extracted with ethyl acetate as the solvent. the resulting extract was subjected to disk diffusion test using kirby bauer method for checking its antimicrobial potential. melon extract showed promising results against different clinical path ...201627013507
shiga toxins as multi-functional proteins: induction of host cellular stress responses, role in pathogenesis and therapeutic applications.shiga toxins (stxs) produced by shiga toxin-producing bacteria shigella dysenteriae serotype 1 and select serotypes of escherichia coli are primary virulence factors in the pathogenesis of hemorrhagic colitis progressing to potentially fatal systemic complications, such as hemolytic uremic syndrome and central nervous system abnormalities. current therapeutic options to treat patients infected with toxin-producing bacteria are limited. the structures of stxs, toxin-receptor binding, intracellula ...201626999205
shiga toxin 1-producing shigella sonnei infections, california, united states, 2014-2015.shiga toxins (stx) are primarily associated with shiga toxin-producing escherichia coli and shigella dysenteriae serotype 1. stx production by other shigellae is uncommon, but in 2014, stx1-producing s. sonnei infections were detected in california. surveillance was enhanced to test s. sonnei isolates for the presence and expression of stx genes, perform dna subtyping, describe clinical and epidemiologic characteristics of case-patients, and investigate for sources of infection. during june 2014 ...201626982255
shiga toxin (stx) classification, structure, and function.shiga toxin (stx) is one of the most potent bacterial toxins known. stx is found in shigella dysenteriae 1 and in some serogroups of escherichia coli (called stx1 in e. coli). in addition to or instead of stx1, some e. coli strains produce a second type of stx, stx2, that has the same mode of action as stx/stx1 but is antigenically distinct. because subtypes of each toxin have been identified, the prototype toxin for each group is now designated stx1a or stx2a. the stxs consist of two major subu ...201426904753
factors affecting inducible expression of outer membrane protein a (ompa) of shigella dysenteriae type-1 in lactococcus lactis using nisin inducible controlled expression (nice).potential use of lactococcus lactis (l. lactis) as a heterologous protein expression host as well as for delivery of multiple therapeutic proteins has been investigated extensively using nisin inducible controlled expression (nice) system. optimum inducible expression of heterologous protein by nice system in l. lactis depends on multiple factors. to study the unexplored role of factors affecting heterologous protein expression in l. lactis using nice, the present study outlines the optimization ...201626843700
antimicrobial properties of a potential probiotic lactobacillus from thai newborn feces.probiotics are increasingly used to treat infectious diarrhea and antibiotic-associated diarrhea. many probiotic bacteria are classified in general such as lactobacillus and are able to colonize the gastrointestinal tracts of infants.201526817219
evaluation of antibacterial activity of plant mediated cao nanoparticles using cissus quadrangularis extract.an assessment of antibacterial activity of greenly synthesized nanoparticles using aqueous stem extract of cissus quadrangularis was carried out. the synthesized nanoparticles were characterized by uv-vis spectroscopy, sem, xrd, ftir and further subjected for antibacterial activity against the pathogens staphylococcus aureus, escherichia coli, klebsiella pneumoniae, pseudomonas aeruginosa, salmonella typhi, shigella dysenteriae and vibrio cholerae. the sem photograph represents cubic and hexagon ...201626723000
evaluation of anti-bacterial effects of some novel thiazole and imidazole derivatives against some pathogenic bacteria.bacterial resistance to antibiotics has motivated the researchers to evaluate the novel anti-bacterial compounds such as some thiazole and imidazole derivatives. thereby, in this work, we investigated the anti-bacterial effects of one new thiazole and two new imidazole derivatives on bacillus cereus, listeria monocytogenes, escherichia coli, salmonella typhimurium, proteus mirabilis and shigella dysenteriae.201526719785
comparative analysis of the shiga toxin converting bacteriophage first detected in shigella sonnei.here we report the first complete nucleotide sequence of a shiga toxin (stx) converting phage from a shigella sonnei clinical isolate that harbors stx1 operon, first identified in the chromosome of shigella dysenteriae type 1. the phage named shigella phage 75/02 stx displayed podoviridae morphology. it proved to be transferable to escherichia coli k-12 strains, and cytotoxicity of the lysogenized strains was demonstrated in vero cell cultures. genomic analysis revealed that the prophage genome ...201626616675
development and evaluation of an up-converting phosphor technology-based lateral flow assay for rapid detection of francisella tularensis.francisella tularensis is a potential biowarfare/bioterrorism agent and zoonotic pathogen that causes tularemia; thus, surveillance of f. tularensis and first-level emergency response using point-of-care testing (poct) are essential. the upt-lf poct assay was established to quantitatively detect f. tularensis within 15 min, and the sensitivity of the assay was 10(4) cfu · ml(-1) (100 cfu/test). the linear quantitative range covered five orders of magnitude, and the coefficients of variation were ...201526608358
synthesis, density functional theory (dft), urease inhibition and antimicrobial activities of 5-aryl thiophenes bearing sulphonylacetamide moieties.a variety of novel 5-aryl thiophenes 4a-g containing sulphonylacetamide (sulfacetamide) groups were synthesized in appreciable yields via pd[0] suzuki cross coupling reactions. the structures of these newly synthesized compounds were determined using spectral data and elemental analysis. density functional theory (dft) studies were performed using the b3lyp/6-31g (d, p) basis set to gain insight into their structural properties. frontier molecular orbital (fmos) analysis of all compounds 4a-g wa ...201526556326
slow relaxation of shape and orientational texture in membrane gel domains.gel domains in lipid bilayers are structurally more complex than fluid domains. growth dynamics can lead to noncircular domains with a heterogeneous orientational texture. most model membrane studies involving gel domain morphology and lateral organization assume the domains to be static. here we show that rosette shaped gel domains, with heterogeneous orientational texture and a central topological defect, after early stage growth, undergo slow relaxation. on a time scale of days to weeks domai ...201526501924
controlling the cytokine storm in severe bacterial diarrhoea with an oral toll-like receptor 4 antagonist.shigella dysenteriae causes the most severe of all infectious diarrhoeas and colitis. we infected rhesus macaques orally and also treated them orally with a small and non-absorbable polypropyletherimine dendrimer glucosamine that is a toll-like receptor-4 (tlr4) antagonist. antibiotics were not given for this life-threatening infection. six days later, the clinical score for diarrhoea, mucus and blood was 54% lower, colon interleukin-8 and interleukin-6 were both 77% lower, and colon neutrophil ...201626496144
stx-producing shigella species from patients in haiti: an emerging pathogen with the potential for global spread.shiga toxins (stx) are commonly produced by shigella dysenteriae serotype 1 and stx-producing escherichia coli. however, the toxin genes have been detected in additional shigella species. we recently reported the emergence of stx-producing shigella in travelers in the united states and france who had recently visited hispaniola (haiti and the dominican republic). in this study, we confirm this epidemiological link by identifying stx-producing shigella from haitian patients attending clinics near ...201526484357
immunization of mice with a live transconjugant shigella hybrid strain induced th1 and th17 cell-mediated immune responses and confirmed passive protection against heterologous shigellae.an avirulent, live transconjugant shigella hybrid (ltshδstx) strain was constructed in our earlier study by introducing a plasmid vector, ppr1347, into a shiga toxin gene deleted shigella dysenteriae 1. three successive oral administrations of ltshδstx to female adult mice produced comprehensive passive heterologous protection in their offspring against challenge with wild-type shigellae. production of no and different cytokines such asil-12p70, il-1β and il-23 in peritoneal mice macrophages ind ...201626478541
shiga toxins: potent poisons, pathogenicity determinants, and pharmacological agents.the shiga toxins (stxs), also known as vero toxins and previously called shiga-like toxins, are a family of potent protein synthesis inhibitors made by shigella dysenteriae type 1 and some serogroups of escherichia coli that cause bloody diarrhea in humans. stxs act as virulence factors for both s. dysenteriae and e. coli and contribute to the disease process initiated by those organisms both directly and indirectly. a handful of methods exist for toxin purification, and the toxins can now even ...200526443514
novel strain of shigella dysenteriae serotype 7 from india.we describe a strain of shigella dysenteriae serotype 7 which had novel biochemical and genetic characters. unlike other s. dysenteriae, it produced gas, fermented mannitol, was a late-lactose fermenter and harboured the set 1a and set 1b genes. the significance of such atypical strains is that they are difficult to identify. if such strains are missed, they could prove to be a serious public health problem because the infectious dose is very low and they may harbour integrons contributing to dr ...201526442152
purification and characterization of a shigella conjugate vaccine, produced by glycoengineering escherichia coli.shigellosis remains a major cause of diarrheal disease in developing countries and causes substantial morbidity and mortality in children. glycoconjugate vaccines consisting of bacterial surface polysaccharides conjugated to carrier proteins are the most effective vaccines for controlling invasive bacterial infections. nevertheless, the development of a multivalent conjugate vaccine to prevent shigellosis has been hampered by the complex manufacturing process as the surface polysaccharide for ea ...201626353918
exoelectrogens leading to precise reduction of graphene oxide by flexibly switching their environment during respiration.reduced graphene oxide (rgo) has been prepared by a simple, cost-effective, and green route. in this work, graphene oxide (go) has been reduced using gram-negative facultative anaerobe s. dysenteriae, having exogenic properties of electron transfer via electron shuttling. apparently, different concentrations of go were successfully reduced with almost complete mass recovery. an effective role of lipopolysaccharide has been observed while comparing rgo reduced by s. dysenteriae and s. aureus. it ...201526288348
expression, purification and immunological characterization of recombinant shiga toxin a subunit.shiga toxin family comprises toxins belonging to two major groups, stx1 and stx2, produced by the bacteria shigella dysenteriae and some strains of escherichia coli. shiga toxins are the leading cause of diarrhea associated with life threatening hemolytic uremic syndrome (hus). stxa is a ribosome inactivating protein (rip) which inhibits the protein synthesis in most species of prokaryotes and eukaryotes. an in vitro expression system has not been reported to produce full-length biological activ ...201526282729
intracellular and membrane-damaging activities of methyl gallate isolated from terminalia chebula against multidrug-resistant shigella spp.shigella spp. (shigella dysenteriae, shigella flexneri, shigella boydii and shigella sonnei) cause bacillary dysentery (shigellosis), which is characterized by bloody mucous diarrhoea. although a variety of antibiotics have been effective for treatment of shigellosis, options are becoming limited due to globally emerging drug resistance. in the present study, in vitro antibacterial activity of methyl gallate (mg) isolated from terminalia chebula was determined by performing mic, minimal bacteric ...201526272388
in vitro and in vivo examination of anticolonization of pathogens by lactobacillus paracasei fj861111.1.very limited information exists on the exclusion of pathogens by probiotics in the gut of the host challenged with pathogens. in this study, we tested probiotic characteristics in vitro and anticolonization ability of lactobacillus paracasei fj861111.1 in mice infected with selected pathogenic microorganisms. the in vitro results indicated that l. paracasei fj861111.1 had a high survival in acidic conditions at ph 2.5 and bile salt concentration at 0.3%, and strong inhibition ability against com ...201526254535
[blood groups - minuses and pluses. do the blood group antigens protect us from infectious diseases?].human blood can be divided into groups, which is a method of blood classification based on the presence or absence of inherited erythrocyte surface antigens that can elicit immune response. according to the international society of blood transfusion, there are 341 blood group antigens collected in 35 blood group systems. these antigens can be proteins, glycoproteins or glycosphingolipids, and function as transmembrane transporters, ion channels, adhesion molecules or receptors for other proteins ...201526206987
inhibition of pathogenic bacterial growth on excision wound by green synthesized copper oxide nanoparticles leads to accelerated wound healing activity in wistar albino rats.an impaired wound healing is one of the major health related problem in diabetic and non-diabetic patients around the globe. the pathogenic bacteria play a predominant role in delayed wound healing, owing to interaction in the wound area. in our previous work we developed green chemistry mediated copper oxide nanoparticles using ficus religiosa leaf extract. in the present study we make an attempt to evaluate the anti-bacterial, and wound healing activity of green synthesized copper oxide nanopa ...201526194977
safety and immunogenicity of a candidate bioconjugate vaccine against shigella dysenteriae type 1 administered to healthy adults: a single blind, partially randomized phase i study.shigellae cause severe disease in endemic countries, especially in children. several efficacy trials have been conducted with candidate vaccines against shigellae, but the lack of protection, the safety concerns, or manufacturing challenges hindered successful market approval. conjugated vaccines have been shown to be safe and effective for different pathogens (i.e., neisseria meningitidis, shigella pneumonia, haemophilus influenzae). the bio-conjugation technology, exploited here for the shigel ...201526162850
expression, purification and immunological characterization of recombinant shiga toxin a subunit.shiga toxin family comprises toxins belonging to two major groups, stx1 and stx2, produced by the bacteria shigella dysenteriae and some strains of escherichia coli. shiga toxins are the leading cause of diarrhea associated with life threatening hemolytic uremic syndrome (hus). stxa is a ribosome inactivating protein (rip) which inhibits the protein synthesis in most species of prokaryotes and eukaryotes. an in vitro expression system has not been reported to produce full- length biological acti ...201526149398
synthesis, chiral separation, absolute configuration assignment, and biological activity of enantiomers of retro-1 as potent inhibitors of shiga toxin.the shiga toxin (stx) family is composed of related protein toxins produced by the bacteria shigella dysenteriae and certain pathogenic strains of e. coli. no effective therapies for stx intoxication have been developed yet. however, inhibitors that act on the intracellular trafficking of these toxins may provide new options for the development of therapeutic strategies. this study reports the synthesis, chromatographic separation, and pharmacological evaluation of the two enantiomers of retro-1 ...201526033849
prevalence of shiga toxin-producing shigella species isolated from french travellers returning from the caribbean: an emerging pathogen with international implications.shiga toxins (stxs) are potent cytotoxins that inhibit host cell protein synthesis, leading to cell death. classically, these toxins are associated with intestinal infections due to stx-producing escherichia coli or shigella dysenteriae serotype 1, and infections with these strains can lead to haemolytic-uraemic syndrome. over the past decade, there has been increasing recognition that stx is produced by additional shigella species. we recently reported the presence and expression of stx genes i ...201525980352
in vitro antibacterial and in vivo cytotoxic activities of grewia paniculata.grewia paniculata (family: malvaceae) has been used to treat inflammation, respiratory disorders and fever. it is additionally employed for other health conditions including colds, diarrhea and as an insecticide in bangladesh. the aim of the present study was to investigate the antibacterial and cytotoxic activities of different extracts of grewia paniculata.025949950
high mean water vapour pressure promotes the transmission of bacillary dysentery.bacillary dysentery is an infectious disease caused by shigella dysenteriae, which has a seasonal distribution. external environmental factors, including climate, play a significant role in its transmission. this paper identifies climate-related risk factors and their role in bacillary dysentery transmission. harbin, in northeast china, with a temperate climate, and quzhou, in southern china, with a subtropical climate, are chosen as the study locations. the least absolute shrinkage and selectio ...201525946209
a novel method for screening of potential probiotics for high adhesion capability.to screen for potential probiotics with high adhesion capability, a chemostat model-based cultured human feces and denaturing gradient gel electrophoresis methods were applied, and the adhesion capability of the isolates was evaluated in vitro and in vivo. lactobacillus plantarum (hm218749), lactobacillus reuteri (eu547310), and enterococcus faecalis (hm218543) were isolated from the slime on the chemostat wall, as these organisms could grow better at 37°c in an anaerobic environment and could r ...201525912863
detection of e. coli o157:h7 and shigella dysenteriae toxins in clinical samples by pcr-elisa.shiga toxin producing bacteria are potential causes of serious human disease such as hemorrhagic colitis, severe inflammations of ileocolonic regions of gastrointestinal tract, thrombocytopenia, septicemia, malignant disorders in urinary ducts, hemolytic uremic syndrome (hus). shiga toxin 1 (stx1), shiga toxin 2 (stx2), or a combination of both are responsible for most clinical symptoms of these diseases. a lot of methods have been developed so far to detect shiga toxins such as cell culture, el ...201525911087
antibacterial and antispasmodic activities of a dichloromethane fraction of an ethanol extract of stem bark of piliostigma reticulatum.this study presents the antispasmodic and antibacterial properties of an ethanol extract and fractions the of stem bark of piliostigma reticulatum.201725883517
antibacterial, antifungal, and insecticidal potentials of oxalis corniculata and its isolated compounds.oxalis corniculata is a common medicinal plant widely used against numerous infectious diseases. the agrochemical potential of methanolic extract, n-hexane, chloroform, ethyl acetate, and n-butanol fractions were assessed to measure the antibacterial, antifungal, and insecticidal activities of the plant. the crude, chloroform, and n-butanol soluble fractions showed excellent activities against escherichia coli, shigella dysenteriae, salmonella typhi, and bacillus subtilis but have no activity ag ...201525873973
characterization of indigenous lactobacillus strains for probiotic properties.probiotics are defined as adequate amount of live microorganisms able to confer health benefits on the host. currently, most commercially available probiotic products in the market belong to genera lactobacillus. traditional dairy products are usually rich source of lactobacillus strains with significant health benefits. in order to evaluate the probiotic potential of these bacteria, it is essential to assess their health benefits, efficacy, and safety.201525793099
prevalence of enteropathogenic bacteria in treated effluents and receiving water bodies and their potential health risks.the failure of wastewater treatment plants to produce effluents of a high microbiological quality is a matter of great concern in terms of water resource pollution. a more serious concern is that this water source is used by communities in developing countries for multiple purposes, which include drinking, recreation and agriculture. the current study investigated the prevalence and potential health risks of enteropathogenic bacteria (salmonella typhimurium, shigella dysenteriae and vibrio chole ...201525777950
the genome of shigella dysenteriae strain sd1617 comparison to representative strains in evaluating pathogenesis.we sequenced and analyzed shigella dysenteriae strain sd1617 serotype 1 that is widely used as model strain for vaccine design, trials and research. a combination of next-generation sequencing platforms and assembly yielded two contigs representing a chromosome size of 4.34 mb and the large virulence plasmid of 177 kb. this genome sequence is compared with other shigella genomes in order to understand gene complexity and pathogenic factors.201525743074
virulence variations in shigella and enteroinvasive escherichia coli using the caenorhabditis elegans model.shigella species and enteroinvasive escherichia coli (eiec) belong to the same species genetically, with remarkable phenotypic and genomic similarities. shigella is the main cause of bacillary dysentery with around 160 million annual cases, while eiec generally induces a milder disease compared to shigella. this study aimed to determine virulence variations between shigella and eiec using the nematode caenorhabditis elegans as a model host. caenorhabditis elegans killing- and bacterial colonizat ...201525673655
shigella outer membrane protein pssp-1 is broadly protective against shigella infection.in developing countries, shigella is a primary cause of diarrhea in infants and young children. although antibiotic therapy is an effective treatment for shigellosis, therapeutic options are narrowing due to the emergence of antibiotic resistance. thus, preventive vaccination could become the most efficacious approach for controlling shigellosis. we have identified several conserved protein antigens that are shared by multiple shigella serotypes and species. among these, one antigen induced cros ...201525651919
antibacterial efficacy of five medicinal plants against multidrug-resistant enteropathogenic bacteria infecting under-5 hospitalized children.to evaluate in vitro antibacterial effectiveness of five medicinal plants used by an indian aborigine, against 8 multidrug-resistant (mdr) enteropathogenic bacteria isolated from clinical samples of under-5 hospitalized children.201525609371
characterization of new myoviridae bacteriophage wz1 against multi-drug resistant (mdr) shigella dysenteriae.shigella dysenteriae is a normal inhabitant of the human gastrointestinal tract, but sometimes it causes severe infection known as shigellosis (bacillary dysentery). bacteriophages are considered very safe and effective agents for controlling bacterial infections and contaminations. in this study, we describe the isolation and characterization of bacteriophage wz1, isolated from waste water which inhibits the growth of s. dysenteriae. phage wz1 showed maximum stability at 37 °c and was stable up ...201525557472
shiga toxin (stx) classification, structure, and function.shiga toxin (stx) is one of the most potent bacterial toxins known. stx is found in shigella dysenteriae 1 and in some serogroups of escherichia coli (called stx1 in e. coli). in addition to or instead of stx1, some e. coli strains produce a second type of stx, stx2, that has the same mode of action as stx/stx1 but is antigenically distinct. because subtypes of each toxin have been identified, the prototype toxin for each group is now designated stx1a or stx2a. the stxs consist of two major subu ...201425530917
molecular characterization of multidrug-resistant shigella spp. of food origin.shigella spp. are the causative agents of food-borne shigellosis, an acute enteric infection. the emergence of multidrug-resistant clinical isolates of shigella presents an increasing challenge for clinicians in the treatment of shigellosis. several studies worldwide have characterized the molecular basis of antibiotic resistance in clinical shigella isolates of human origin, however, to date, no such characterization has been reported for shigella spp. of food origin. in this study, we characte ...201525485847
shiga toxin-induced apoptosis is more efficiently inhibited by dimeric recombinant hybrid-igg/iga immunoglobulins than by the parental igg monoclonal antibodies.shiga toxin 1 (stx1) is a virulence factor of enterohaemorrhagic escherichia coli strains such as o157:h7 and shigella dysenteriae. to prevent entry of stx1 from the mucosal surface, an immunoglobulin a (iga) specific for stx1 would be useful. due to the difficulty of producing iga monoclonal antibodies (mab) against the binding subunit of stx1 (stx1b) in mice, we took advantage of recombinant technology that combines the heavy chain variable region from stx1b-specific igg1 mab and the fc region ...201425469594
evaluation of antibacterial and anthelmintic activities with total phenolic contents of piper betel leaves.the study was conducted to investigate the antibacterial and anthelmintic activities and to determine total phenolic contents of methanolic extract of piper betel leaves.201425386394
synthesis of an aminooxy derivative of the trisaccharide globotriose gb3.the synthesis of α-aminooxy trisaccharide moiety [α-d-gal-(1,4)-β-d-gal-(1,4)-β-d-glc-α-aminooxy], related to the cell surface globotriaosylceramide (gb3) receptor of the b subunit of the ab5 shiga toxin of shigella dysenteriae, has been synthesized for the first time in 11 steps with a 15% overall isolated yield. a highlight of this work entails utilizing chemically compatible synthetic transformations, including those related to glycosylation, incorporative of the succinimidyl moiety as a prec ...201425382930
the preliminary assessment of anti-microbial activity of hplc separated components of kirkia wilmsii.most communities in developing countries rely on traditional medicines for the treatment of diseases. in south africa, the limpopo province, within the lebowakgomo district, uses tuberous roots of kirkia wilmsii, after infusion in water for the treatment of a wide range of diseases by sotho communities.201425371593
shigella dysenteriae modulates bmp pathway to induce mucin gene expression in vivo and in vitro.mucosal epithelial cells in the intestine act as the first line of host defense against pathogens by increasing mucin production for clearance. despite this fact, the underlying molecular mechanisms by which shigella dysenteriae transduce mucin gene expression remain poorly defined. the goal of this study was to determine the role of bone morphogenetic protein (bmp) pathway in mucin gene expression during s. dysenteriae infection. in this study we demonstrate that s. dysenteriae activates bmp si ...201425365201
an in vitro antibacterial and antifungal effects of cadmium(ii) complexes of hexamethyltetraazacyclotetradecadiene and isomers of its saturated analogue.to evaluate the antibacterial and antifungal effects of cadmium(ii) complexes with hexamethyltetraazacyclotetradecadiene ligands.201425312179
antibacterial activity of ethyl acetate and aqueous extracts of mentha longifolia l. and hydroalcoholic extract of zataria multiflora boiss. plants against important human pathogens.to determine the potential antibacterial activity of ethyl acetate and aqueous extracts from mentha longifolia l. (m. longifolia) and hydroalcoholic extract of zataria multiflora boiss. (z. multiflora) against important human pathogens.201425312118
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
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
isolation and development of bioluminescent reporter phages for bacterial dysentery.shigellosis is a significant cause of morbidity and mortality worldwide, most notably amongst children. moreover, there is a global increase in the occurrence of multidrug-resistant isolates, including the epidemic and pandemic shigella dysenteriae type 1 strain. we developed a bioluminescent reporter phage assay to facilitate detection and simultaneously determine antibiotic susceptibility. a shigella flexneri phage (shfl25875) was isolated from environmental wastewater and characterized by dna ...201525252629
hijacking bacterial glycosylation for the production of glycoconjugates, from vaccines to humanised glycoproteins.glycosylation or the modification of a cellular component with a carbohydrate moiety has been demonstrated in all three domains of life as a basic post-translational process important in a range of biological processes. this review will focus on the latest studies attempting to exploit bacterial n-linked protein glycosylation for glycobiotechnological applications including glycoconjugate vaccine and humanised glycoprotein production. the challenges that remain for these approaches to reach full ...201425244672
total phenolic content and antibacterial activity of five plants of labiatae against four foodborne and some other bacteria.the aim of this study was to evaluate the antibacterial effects of thymus vulgaris, thymus caramanicus, zataria multiflora, ziziphora clinopodioides and ziziphora tenuior against four foodborne and four other bacteria including staphylococcus aureus, shigella dysenteriae, salmonella typhimurium, escherichia coli, staphylococcus epidermidis, bacillus subtilis, mrsa and pseudomona aeruginosa and measuring the amount of total phenolics of the plants. the extracts were prepared by maceration method. ...201425237351
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
antibacterial and antifungal activity of holothuria leucospilota isolated from persian gulf and oman sea.emergence of antimicrobial resistance toward a number of conventional antibiotics has triggered the search for antimicrobial agents from a variety of sources including the marine environment.201425147657
effect of water storage in silver container on the viability of enteric bacterial pathogens.silver is one of the heavy metals traditionally played major role in the human life. it is used in the form of ornaments or as containers to store or drink water and other consumable liquids. the study was designed to observe the effect of water storage in silver containers on enteric pathogens. three sets of sterile silver, stainless steel and glass metal screw capped containers were filled with non-chlorinated sterilized well water. one each of the three sets was inoculated with enteric pathog ...201225145073
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
lethal synergy involving bicyclomycin: an approach for reviving old antibiotics.one way to address the growing problem of antimicrobial resistance is to revive old compounds that may have intrinsic lethal activity that is obscured by protective factors. bicyclomycin is an old inhibitor of the rho transcription terminator that by itself shows little rapid lethal activity. however, bicyclomycin participates in bacteriostatic synergy, which raises the possibility that conditions for lethal synergy may exist, perhaps through a suppression of protective factors.201425085655
effect of shiga toxin and its subunits on cytokine induction in different cell lines.shiga toxins (stxs) are bacterial virulence factors produced by shigella dysenteriae serotype 1 and escherichia coli strains. stxs are critical factors for the development of diseases such as severe bloody diarrhea and hemolytic uremic syndrome. additionally, stxs trigger the secretion of pro- inflammatory cytokines and chemokines, particularly in monocytes or macrophages. the inflammatory cytokines result in the modulation of the immune system, local inflammations and enhancement of cytotoxicit ...201425035861
use of plant extracts to control and treat ab5 enterotoxin-related diarrhea.plants contain a broad spectrum of small molecules with potential antimicrobial properties. here, we review the antimicrobial activities of plant extracts against enterotoxic bacteria encoding ab5 toxins, including vibrio cholerae, shigella dysenteriae and enterotoxic escherichia coli strains. several plant extracts have strong antimicrobial effects and the potential to boost oral rehydration therapy, which is the first line of treatment for acute diarrhea.201425033656
genome sequencing, annotation and comparative genomic analysis of shigella dysenteriae strain sd1d.shigellosis is an acute form of gastroenteritis caused by the bacteria belonging to the genus shigella. it is the most common cause of morbidity and mortality in children. shigella belongs to the family enterobactericeae, which is a gram-negative and rod shaped bacterium. in the present study, we report the draft genome of shigella dysenteriae strain sd1d, which was isolated from the stool sample of a healthy individual.201425028600
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