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gene fitness landscapes of vibrio cholerae at important stages of its life cycle.vibrio cholerae has evolved to adeptly transition between the human small intestine and aquatic environments, leading to water-borne spread and transmission of the lethal diarrheal disease cholera. using a host model that mimics the pathology of human cholera, we applied high density transposon mutagenesis combined with massively parallel sequencing (tn-seq) to determine the fitness contribution of >90% of all non-essential genes of v. cholerae both during host infection and dissemination. targe ...201324385900
environmental reservoirs and mechanisms of persistence of vibrio cholerae.it is now well accepted that vibrio cholerae, the causative agent of the water-borne disease cholera, is acquired from environmental sources where it persists between outbreaks of the disease. recent advances in molecular technology have demonstrated that this bacterium can be detected in areas where it has not previously been isolated, indicating a much broader, global distribution of this bacterium outside of endemic regions. the environmental persistence of v. cholerae in the aquatic environm ...201324379807
genomic epidemiology of vibrio cholerae o1 associated with floods, pakistan, 2010.in august 2010, pakistan experienced major floods and a subsequent cholera epidemic. to clarify the population dynamics and transmission of vibrio cholerae in pakistan, we sequenced the genomes of all v. cholerae o1 el tor isolates and compared the sequences to a global collection of 146 v. cholerae strains. within the global phylogeny, all isolates from pakistan formed 2 new subclades (psc-1 and psc-2), lying in the third transmission wave of the seventh-pandemic lineage that could be distingui ...201424378019
[application of pulsenet china database in tracking and warning 4 cholerae outbreaks in anhui province, in 2012].to track the source of infection regarding 4 cholerae outbreaks in anhui province in 2012 through the application of pulsenet china database (pncd).201324377996
[epidemiological and etiological characteristics of diarrheal disease among children under 5 years of age in guangdong province, in 2012].to analyze the epidemiological and etiological characteristics of diarrheal disease among children under 5 years of age in guangdong province, in 2012.201324377993
genetic variation of vibrio cholerae during outbreaks, bangladesh, 2010-2011.cholera remains a major public health problem. to compare the relative contribution of strains from the environment with strains isolated from patients during outbreaks, we performed multilocus variable tandem repeat analyses on samples collected during the 2010 and 2011 outbreak seasons in 2 geographically distinct areas of bangladesh. a total of 222 environmental and clinical isolates of v. cholerae o1 were systematically collected from chhatak and mathbaria. in chhatak, 75 of 79 isolates were ...201424377372
zebrafish as a natural host model for vibrio cholerae colonization and transmission.the human diarrheal disease cholera is caused by the aquatic bacterium vibrio cholerae. v. cholerae in the environment is associated with several varieties of aquatic life, including insect egg masses, shellfish, and vertebrate fish. here we describe a novel animal model for v. cholerae, the zebrafish. pandemic v. cholerae strains specifically colonize the zebrafish intestinal tract after exposure in water with no manipulation of the animal required. colonization occurs in close contact with the ...201424375135
cqsa-cqss quorum-sensing signal-receptor specificity in photobacterium angustum.quorum sensing (qs) is a process of bacterial cell-cell communication that relies on the production, detection and population-wide response to extracellular signal molecules called autoinducers. the qs system commonly found in vibrios and photobacteria consists of the cqsa synthase/cqss receptor pair. vibrio cholerae cqsa/s synthesizes and detects (s)-3-hydroxytridecan-4-one (c10-cai-1), whereas vibrio harveyi produces and detects a distinct but similar molecule, (z)-3-aminoundec-2-en-4-one (ea- ...201424372841
[antibiotic susceptibility of vibrio cholerae non o1/non o139 serogroups isolated from environment in the rostov region].analysis of the antibioticograms of 22 strains of vibrio cholerae non o1/non o139 serogroups (ctxa- tepa-) isolated from the environment in the rostov region in 2011 showed that all the cultures were susceptible to ciprofloxacin, aminoglycosides, ceftriaxone, trimetoprime/sulfamethoxazole and resistant to levomycetin and furazolidone. 32%, 18% and 9% of the isolates were resistant to tetracycline, rifampicin and nalidixic acid respectively. no strains of v. cholerae susceptible to all the tested ...201426448988
haitian variant tcpa in vibrio cholerae o1 el tor strains in kolkata, india. 201424371245
cholera outbreaks in the classical biotype era.in the indian subcontinent description of a disease resembling cholera has been mentioned in sushruta samita, estimated to have been written between ~400 and 500 bc. it is however not clear whether the disease known today as cholera caused by vibrio cholerae vibrio cholerae o1 is the evolutionary progression of the ancient disease. the modern history of cholera began in 1817 when an explosive epidemic broke out in the ganges river delta region of bengal. this was the first of the seven recorded ...201424368696
comparative genomics study for identification of drug and vaccine targets in vibrio cholerae: mura ligase as a case study.a systematic workflow consisting of comparative genomics, metabolic pathways analysis and additional drug prioritization parameters identified 264 proteins of vibrio cholerae which were predicted to be absent in homo sapiens. among these, 40 proteins were identified as essential proteins that could serve as potential drug and vaccine targets. additional prioritization parameters characterized 11 proteins as vaccine candidates while druggability of each of the identified proteins as evaluated by ...201424368230
vibrio cholerae interactions with mytilus galloprovincialis hemocytes mediated by serum components.edible bivalves (e.g., mussels, oysters) can accumulate large amount of bacteria in their tissues and act as passive carriers of pathogens to humans. bacterial persistence inside bivalves depends, at least in part, on hemolymph anti-bacterial activity that is exerted by both serum soluble factors and phagocytic cells (i.e., the hemocytes). it was previously shown that mytilus galloprovincialis hemolymph serum contains opsonins that mediate d-mannose-sensitive interactions between hemocytes and v ...201324367358
the luxr-type regulator vpst negatively controls the transcription of rpos, encoding the general stress response regulator, in vibrio cholerae biofilms.cholera is a waterborne diarrheal disease caused by vibrio cholerae strains of serogroups o1 and o139. expression of the general stress response regulator rpos and formation of biofilm communities enhance the capacity of v. cholerae to persist in aquatic environments. the transition of v. cholerae between free-swimming (planktonic) and biofilm life-styles is regulated by the second messenger cyclic di-gmp (c-di-gmp). we previously reported that increasing the c-di-gmp pool by overexpression of a ...201424363348
inhibition of the sodium-translocating nadh-ubiquinone oxidoreductase [na+-nqr] decreases cholera toxin production in vibrio cholerae o1 at the late exponential growth phase.two virulence factors produced by vibrio cholerae, cholera toxin (ct) and toxin-corregulated pilus (tcp), are indispensable for cholera infection. toxt is the central regulatory protein involved in activation of ct and tcp expression. we previously reported that lack of a respiration-linked sodium-translocating nadh-ubiquinone oxidoreductase (na(+)-nqr) significantly increases toxt transcription. in this study, we further characterized this link and found that na(+)-nqr affects toxt expression o ...201424361395
the β-prism lectin domain of vibrio cholerae hemolysin promotes self-assembly of the β-pore-forming toxin by a carbohydrate-independent mechanism.vibrio cholerae cytolysin/hemolysin (vcc) is an amphipathic 65-kda β-pore-forming toxin with a c-terminal β-prism lectin domain. because deletion or point mutation of the lectin domain seriously compromises hemolytic activity, it is thought that carbohydrate-dependent interactions play a critical role in membrane targeting of vcc. to delineate the contributions of the cytolysin and lectin domains in pore formation, we used wild-type vcc, 50-kda vcc (vcc(50)) without the lectin domain, and mutant ...201424356964
the seventh pandemic vibrio cholerae o1 el tor isolate in china has undergone genetic shifts.a total of 330 clinical vibrio cholerae o1 serogroups from china dating between 1961 and 2010 were investigated. by phenotypic biotyping and genetic analysis, during the seventh pandemic of v. cholerae o1 in china, the isolates of hybrid biotype (mixed classical phenotypes) were present during the entire1961-2010 period, while el tor genetic shifts appeared in 1992 and replaced the prototype el tor from 2002 to 2010.201424353005
the selectivity of vibrio cholerae h-nox for gaseous ligands follows the "sliding scale rule" hypothesis. ligand interactions with both ferrous and ferric vc h-nox.vc h-nox (or vca0720) is an h-nox (heme-nitric oxide and oxygen binding) protein from facultative aerobic bacterium vibrio cholerae. it shares significant sequence homology with soluble guanylyl cyclase (sgc), a no sensor protein commonly found in animals. similar to sgc, vc h-nox binds strongly to no and co with affinities of 0.27 nm and 0.77 μm, respectively, but weakly to o2. when positioned on a "sliding scale" plot [tsai, a.-l., et al. (2012) biochemistry 51, 172-186], the line connecting l ...201324351060
vibrio cholerae o1 epidemic variants in angola: a retrospective study between 1992 and 2006.cholera is still a major public health concern in many african countries. in angola, after a decade of absence, cholera reemerged in 1987, spreading throughout the country until 1996, with outbreaks recurring in a seasonal pattern. in 2006 angola was hit by one of the most severe outbreaks of the last decade, with ca. 240,000 cases reported. we analyzed 21 clinical strains isolated between 1992 and 2006 from several provinces throughout the country: benguela, bengo, luanda, cuando cubango, and c ...201324348465
[effect of plant extracts on cytotoxic activity of vibrio cholerae hemolysin].study of plant extracts that have the ability to neutralize cytotoxic activity of hemolysin.201324341209
a cluster of cholera among patients in a vietnamese district hospital in 2010.on july 20, 2010, three cases of cholera were reported from a district hospital in ca mau province, vietnam. we investigated the likely source and mode of transmission of the outbreak. all hospitals in the province were requested to notify cases of acute watery diarrhoea. epidemiological, clinical, and laboratory data were collected. between july 12 and 22, seven cases with positive culture for vibrio cholera were identified. six cases were epidemiologically linked to the index case. basic infec ...201324334936
relationship of aquatic environmental factors with the abundance of vibrio cholerae, vibrio parahaemolyticus, vibrio mimicus and vibrio vulnificus in the coastal area of guaymas, sonora, mexico.members of the genus vibrio are common in aquatic environments. among them are v. cholerae, v. vulnificus, v. parahaemolyticus and v. mimicus. several studies have shown that environmental factors, such as temperature, salinity, and dissolved oxygen, are involved in their epidemiology. therefore, the main objective of this study is to determine if there is a correlation between the presence/amount of v. cholerae, v, vulnificus, v. parahaemolyticus and v. mimicus and the environmental conditions ...201324334844
solutions to the public goods dilemma in bacterial biofilms.bacteria frequently live in densely populated surface-bound communities, termed biofilms [1-4]. biofilm-dwelling cells rely on secretion of extracellular substances to construct their communities and to capture nutrients from the environment [5]. some secreted factors behave as cooperative public goods: they can be exploited by nonproducing cells [6-11]. the means by which public-good-producing bacteria avert exploitation in biofilm environments are largely unknown. using experiments with vibrio ...201424332540
tn-seq analysis of vibrio cholerae intestinal colonization reveals a role for t6ss-mediated antibacterial activity in the host.analysis of genes required for host infection will provide clues to the drivers of evolutionary fitness of pathogens like vibrio cholerae, a mounting threat to global heath. we used transposon insertion site sequencing (tn-seq) to comprehensively assess the contribution of nearly all v. cholerae genes toward growth in the infant rabbit intestine. four hundred genes were identified as critical to v. cholerae in vivo fitness. these included most known colonization factors and several new genes aff ...201324331463
comparative phenotypic characterization of vibrio cholerae isolates collected from aquatic environments of georgia.vibrio cholerae is ubiquitous in aquatic environment inhabiting marine, fresh and brackish waters. v. cholerae serotypes o1 and o139 cause the devastating diarrheal disease cholera, which is often fatal without proper treatment. little is known regarding the abundance and diversity of clinically important nonhalophilic vibrios in the south caucasus region, particularly in georgia. here we provide the data on the georgian environmental strains of v. cholerae isolated in 2006-2009 years from the c ...201324323966
vibrio cholerae antimicrobial drug resistance, papua new guinea, 2009-2011. 201324319616
the 1.59å resolution structure of the minor pseudopilin epsh of vibrio cholerae reveals a long flexible loop.the type ii secretion complex exports folded proteins from the periplasm to the extracellular milieu. it is used by the pathogenic bacterium vibrio cholerae to export several proteins, including its major virulence factor, cholera toxin. the pseudopilus is an essential component of the type ii secretion system and likely acts as a piston to push the folded proteins across the outer membrane through the secretin pore. the pseudopilus is composed of the major pseudopilin, epsg, and four minor pseu ...201424316251
fuse or die: how to survive the loss of dam in vibrio cholerae.dam methylates gatc sequences in γ-proteobacteria genomes, regulating several cellular functions including replication. in vibrio cholerae, which has two chromosomes, dam is essential for viability, owing to its role in chr2 replication initiation. in this study, we isolated spontaneous mutants of v. cholerae that were able to survive the deletion of dam. in these mutants, homologous recombination and chromosome dimer resolution are essential, unless dna mismatch repair is inactivated. furthermo ...201424308271
zinc: role in the management of diarrhea and cholera.diarrhea and cholera are major health problems. vibrio cholera, the causative agent of cholera, infects the small intestine, resulting in vomiting, massive watery diarrhea and dehydration. reduced water and electrolyte absorption is also due to zinc deficiency. zinc has an important role in recovery from the disease. the combination of zinc with cholera vaccine and oral rehydration solutions has a positive impact on cholera and diarrhea. it has led to a decrease in the mortality and morbidity as ...201324303485
population and genetic study of vibrio cholerae from the amazon environment confirms that the wasa-1 prophage is the main marker of the epidemic strain that circulated in the region.vibrio cholerae is a natural inhabitant of many aquatic environments in the world. biotypes harboring similar virulence-related gene clusters are the causative agents of epidemic cholera, but the majority of strains are harmless to humans. since 1971, environmental surveillance for potentially pathogenic v. cholerae has resulted in the isolation of many strains from the brazilian amazon aquatic ecosystem. most of these strains are from the non-o1/non-o139 serogroups (nags), but toxigenic o1 stra ...201324303045
extracellular proteolytic enzymes produced by human pathogenic vibrio species.bacteria in the genus vibrio produce extracellular proteolytic enzymes to obtain nutrients via digestion of various protein substrates. however, the enzymes secreted by human pathogenic species have been documented to modulate the bacterial virulence. several species including vibrio cholerae and v. vulnificus are known to produce thermolysin-like metalloproteases termed vibriolysin. the vibriolysin from v. vulnificus, a causative agent of serious systemic infection, is a major toxic factor elic ...201324302921
investigation of a cholera outbreak in a tea garden of sivasagar district of assam.in late may 2012, bagjan division of borbam tea estate, of sivasagar district of assam was affected by an outbreak of acute watery diarrhea, subsequently confirmed as vibrio cholerae o1.201324302826
pre-pore oligomer formation by vibrio cholerae cytolysin: insights from a truncated variant lacking the pore-forming pre-stem loop.vibrio cholerae cytolysin (vcc), a β-barrel pore-forming toxin (β-pft), induces killing of the target eukaryotic cells by forming heptameric transmembrane β-barrel pores. consistent with the β-pft mode of action, binding of the vcc toxin monomers with the target cell membrane triggers formation of pre-pore oligomeric intermediates, followed by membrane insertion of the β-strands contributed by the pre-stem motif within the central cytolysin domain of each protomer. it has been shown previously t ...201424291710
distribution of vibrio species in shellfish and water samples collected from the atlantic coastline of south-east nigeria.crayfish, lobster, and sea-water samples collected from five fishing islands on the atlantic coast-bight of biafra (bonny)-belonging to ibaka local government area of akwa-ibom state of nigeria were bacteriologically evaluated on thiosulphate citrate bile-salt sucrose (tcbs) agar for vibrio load and pathotypes. mean log10 vibrio counts of 7.64+/-2.78 cfu/g (in crayfish), 5.07+/-3.21 cfu/g (in lobster), and 3.06+/-2.27 cfu/ml (in sea-water) were obtained in rainy season (june-july) while counts i ...201324288944
cholera: environmental reservoirs and impact on disease transmission.vibrio cholerae is widely known to be the etiological agent of the life-threatening diarrheal disease cholera. cholera remains a major scourge in many developing countries, infecting hundreds of thousands every year. remarkably, v. cholerae is a natural inhabitant of brackish riverine, estuarine, and coastal waters, and only a subset of strains are known to be pathogenic to humans. recent studies have begun to uncover a very complex network of relationships between v. cholerae and other sea dwel ...201326184966
a 6-week oral toxicity study of oral cholera vaccine in sprague-dawley rats.the present study was carried out to examine the toxicity and target organs of oral cholera vaccine (ocv) after repeated oral administration in sprague-dawley rats for 6 weeks (3 administrations, once every 2 weeks). ocv is an inactivated oral cholera vaccine that contains vibrio cholerae and confers protection against cholera caused by v. cholera serogroups o1 (inaba and ogawa serotypes) and o139 (strain 4260b). the animals were orally administered either ocv placebo (negative control) or ocv a ...201224278614
genome sequences of clinical vibrio cholerae isolates from an oyster-borne cholera outbreak in florida.between november 2010 and april 2011, 11 cases of cholera were identified and associated with the consumption of raw oysters harvested from apalachicola bay, florida. the etiological agent was the ctxab-positive vibrio cholerae serogroup o75. the genome sequences of the isolates provide useful information and are deposited in the public genome databases.201324265497
efficient responses to host and bacterial signals during vibrio cholerae colonization.vibrio cholerae, the microorganism responsible for the diarrheal disease cholera, is able to sense and respond to a variety of changing stimuli in both its aquatic and human gastrointestinal environments. here we present a review of research efforts aimed toward understanding the signals this organism senses in the human host. v. cholerae's ability to sense and respond to temperature and ph, bile, osmolarity, oxygen and catabolite levels, nitric oxide, and mucus, as well as the quorum sensing si ...201724256715
changing patient population in dhaka hospital and matlab hospital of icddr,b.the diarrhoeal disease surveillance system of icddr,b noted increasing number of patients ≥60 years at urban dhaka and rural matlab from 2001 to 2012. shigella and vibrio cholerae were more frequently isolated from elderly people than children under 5 years and adults aged 5-59 in both areas. the resistance observed to various drugs of shigella in dhaka and matlab was trimethoprim-sulphamethoxazole (72-63%), ampicillin (43-55%), nalidixic acid (58-61%), mecillinam (12-9%), azithromycin (13-0%), ...201424252120
high case fatality cholera outbreak in western kenya, august 2010.cholera is a disease caused by the bacterium vibrio cholera and has been an important public health problem since its first pandemic in 1817. kenya has had numerous outbreaks of cholera ever since it was first detected there during 1971. in august 2010 an outbreak of cholera occurred in kuria west district spreading to the neighboring migori district. we conducted an investigation in order to determine the magnitude of the problem and institute control measures.201324244795
outbreak of mass sociogenic illness in a school feeding program in northwest bangladesh, 2010.in 2010, an acute illness outbreak was reported in school students eating high-energy biscuits supplied by the school feeding programme in northwest bangladesh. we investigated this outbreak to describe the illness in terms of person, place and time, develop the timeline of events, and determine the cause and community perceptions regarding the outbreak.201324244685
cholera toxin expression by el tor vibrio cholerae in shallow culture growth conditions.vibrio cholerae o1 classical, el tor and o139 are the primary biotypes that cause epidemic cholera, and they also express cholera toxin (ct). although classical v. cholerae produces ct in various settings, the el tor and o139 strains require specific growth conditions for ct induction, such as the so-called aki conditions, which consist of growth in static conditions followed by growth under aerobic shaking conditions. however, our group has demonstrated that ct production may also take place in ...201424239941
plasticity of regulation of mannitol phosphotransferase system operon by crp-camp complex in vibrio cholerae.the complex of the cyclic amp receptor protein (crp) and camp is an important transcriptional regulator of numerous genes in prokaryotes. the transport of mannitol through the phosphotransferase systems (pts) is regulated by the crp-camp complex. the aim of the study is to investigate how the crp-camp complex acting on the mannitol pts operon mtl of the vibrio cholerae el tor biotype.201324215877
genetic and phenotypic analysis of vibrio cholerae non-o1, non-o139 isolated from german and austrian patients.vibrio cholerae belonging to the non-o1, non-o139 serogroups are present in the coastal waters of germany and in some german and austrian lakes. these bacteria can cause gastroenteritis and extraintestinal infections, and are transmitted through contaminated food and water. however, non-o1, non-o139 v. cholerae infections are rare in germany. we studied 18 strains from german and austrian patients with diarrhea or local infections for their virulence-associated genotype and phenotype to assess t ...201424213848
role of phages in the epidemiology of cholera.understanding the genetic and ecological factors which support the periodic emergence of toxigenic vibrio cholerae causing outbreaks of cholera in regions where the disease is endemic, is vital to develop preventive measures. besides environmental factors which are not precisely defined, bacteriophages, and horizontally transmissible genetic elements are known to have a significant role in the epidemiology and evolution of the pathogen. cholera epidemics are also known to be self-limiting, and h ...201424213557
single nucleotide polymorphisms of human sting can affect innate immune response to cyclic dinucleotides.the sting (stimulator of interferon genes) protein can bind cyclic dinucleotides to activate the production of type i interferons and inflammatory cytokines. the cyclic dinucleotides can be bacterial second messengers c-di-gmp and c-di-amp, 3'5'-3'5' cyclic gmp-amp (3'3' cgamp) produced by vibrio cholerae and metazoan second messenger 2'5'-3'5' cyclic gmp-amp (2'3' cgamp). analysis of single nucleotide polymorphism (snp) data from the 1000 genome project revealed that r71h-g230a-r293q (haq) occu ...201324204993
[preparation of monoclonal antibodies against flagellin core protein of vibrio cholerae and its application in establishing double-antibody sandwich elisa for testing vibrio cholerae from food products].to prepare the monoclonal antibodies (mabs) against flagellin core protein of vibrio cholerae and establish the double-antibody sandwich elisa method for testing vibrio cholerae from food products.201324200064
adaptation of a simple dipstick test for detection of vibrio cholerae o1 and o139 in environmental water.the presence of vibrio cholerae in the environment is key to understanding the epidemiology of cholera. the gold standard for laboratory confirmation of v. cholerae from water is a culture method, but this requires laboratory infrastructure. a rapid diagnostic test that is simple, inexpensive, and can be deployed widely would be useful for confirming v. cholerae in samples of environmental water. here, we evaluated a dipstick test to detect v. cholerae o1 and o139 from environmental water sample ...201324194737
the greatest steps towards the discovery of vibrio cholerae.in the 19th century, there was extensive research on cholera: the disease was generally attributed to miasmatic causes, but this concept was replaced, between about 1850 and 1910, by the scientifically founded germ theory of disease. in 1883, robert koch identified the vibrion for the second time, after filippo pacini's discovery in 1854: koch isolated the comma bacillus in pure culture and explained its mode of transmission, solving an enigma that had lasted for centuries. the aim of this artic ...201424191858
resveratrol--a potential inhibitor of biofilm formation in vibrio cholerae.resveratrol, a phytochemical commonly found in the skin of grapes and berries, was tested for its biofilm inhibitory activity against vibrio cholerae. biofilm inhibition was assessed using crystal violet assay. mtt assay was performed to check the viability of the treated bacterial cells and the biofilm architecture was analysed using confocal laser scanning microscopy. the possible target of the compound was determined by docking analysis. results showed that subinhibitory concentrations of the ...201424182988
characterization of vibrio cholerae from 1986 to 2012 in yunnan province, southwest china bordering myanmar.vibrio cholerae is an important infectious pathogen causing serious human diarrhea. we analyzed 568 v. cholerae strains isolated from 1986 to 2012 in yunnan province, southwest china bordering myanmar. polymerase chain reactions for detecting virulence genes, antibiotic susceptibility tests and pulse-field gel electrophoresis (pfge) were performed. the results showed all the strains were el tor biotype from 1986. the ctxb subunit sequence analysis for all strains have shown that cholera between ...201424177595
safety and immunogenicity of single-dose live oral cholera vaccine strain cvd 103-hgr, prepared from new master and working cell banks.currently, no cholera vaccine is available for persons traveling from the united states to areas of high cholera transmission and who for reasons of occupation or host factors are at increased risk for development of the disease. a single-dose oral cholera vaccine with a rapid onset of protection would be particularly useful for such travelers and might also be an adjunct control measure for cholera outbreaks. the attenuated vibrio cholerae o1 vaccine strain cvd 103-hgr harbors a 94% deletion of ...201424173028
the hows and whys of constructing a native recombinant cholera vaccine.emergence of different ctxb genotypes within virulent vibrio cholerae populations accentuates the need to develop a vaccine that has the potential to protect against all cholera toxin genotypes. oral administration of rctb-alone and in combination with 2 dominant domestic killed whole cells of v. cholerae (o1 ogawa el tor and o1 inaba el tor) plus one standard v. cholerae (o1 ogawa classic atcc 14035)-has shown satisfactory protection as a potent vaccine candidate against toxigenic v. cholerae.201524165439
multiplex real-time polymerase chain reaction assays for simultaneous detection of vibrio cholerae, vibrio parahaemolyticus, and vibrio vulnificus.a multiplex real-time polymerase chain reaction (rt-pcr) method was developed for the identification of three vibrio species: vibrio cholerae, vibrio parahaemolyticus, and vibrio vulnificus.201324159544
evaluation of colorimetric detection methods for shigella, salmonella, and vibrio cholerae by loop-mediated isothermal amplification.we evaluated loop-mediated isothermal amplification end-point detection methods for salmonella, shigella, and vibrio cholerae. detection sensitivities were comparable to real-time pcr methods. the colorimetric dyes hydroxynaphthol blue and sybr green i showed increased sensitivity when compared to visual and automated turbidity readings. end-point colorimetric dyes promise great utility in developing settings.201324157057
substitution of glutamate residue by lysine in the dimerization domain affects dna binding ability of hapr by inducing structural deformity in the dna binding domain.hapr has been given the status of a high cell density master regulatory protein in vibrio cholerae. though many facts are known regarding its structural and functional aspects, much still can be learnt from natural variants of the wild type protein. this work aims at investigating the nature of functional inertness of a hapr natural variant harboring a substitution of a conserved glutamate residue at position 117 which participates in forming a salt bridge by lysine (haprv2g-e(117)k). experiment ...201324155884
vibrio cholerae and vibrio parahaemolyticus detected in seafood products from senegal.the detection of pathogenic vibrio in seafood from senegal has generated five food alerts in the european union. to investigate the presence and abundance vibrio cholerae and vibrio parahaemolyticus in seafood and coastal and estuarine waters, 123 seafood samples and 52 water samples were collected during 2007-2009 from two large seafood markets in dakar, and from different oceanic and estuarine areas of the country. v. parahaemolyticus was detected in 30.1% of seafood samples, whereas presence ...201324147655
cholera in coastal africa: a systematic review of its heterogeneous environmental determinants.according to the "cholera paradigm," epidemiology of this prototypical waterborne disease is considered to be driven directly by climate-induced variations in coastal aquatic reservoirs of vibrio cholerae. this systematic review on environmental determinants of cholera in coastal africa shows that instead coastal epidemics constitute a minor part of the continental cholera burden. most of coastal cholera foci are located near estuaries, lagoons, mangrove forests, and on islands. yet outbreaks of ...201324101653
national surveillance data on the epidemiology of cholera in cameroon.background. the cholera burden in cameroon has increased during the past 2 decades. during 2010 and 2011, the largest number of cholera cases in cameroon since february 1971 were reported. this article describes cholera outbreaks during 2010-2011. methods. data received from the national surveillance system from 2010 and 2011 were compiled and analyzed. results. the first suspected cholera cases were reported in the far north region on 6 may 2010. in 2010, 10 759 cholera cases were reported by 8 ...201324101652
elimination of cholera in the democratic republic of the congo: the new national policy.we evaluated published and unpublished data on cholera cases and deaths reported from clinical care facilities in the 56 health districts of the democratic republic of congo to the national ministry of health during 2000-2011. cholera incidence was highest in the eastern provinces bordering lakes and epidemics primarily originated in this region. along with a strong seasonal component, our data suggest a potential vibrio cholerae reservoir in the rift valley lakes and the possible contribution o ...201324101651
cholera surveillance in uganda: an analysis of notifications for the years 2007-2011.cholera outbreaks have occurred periodically in uganda since 1971. the country has experienced intervals of sporadic cases and localized outbreaks, occasionally resulting in prolonged widespread epidemics.201324101649
national surveillance data on the epidemiology of cholera in kenya, 1997-2010.kenya has experienced multiple cholera outbreaks since 1971. cholera remains an issue of major public health importance and one of the 35 priority diseases under kenya's updated integrated disease surveillance and response strategy.201324101646
environmental determinants of cholera outbreaks in inland africa: a systematic review of main transmission foci and propagation routes.cholera is generally regarded as the prototypical waterborne and environmental disease. in africa, available studies are scarce, and the relevance of this disease paradigm is questionable. cholera outbreaks have been repeatedly reported far from the coasts: from 2009 through 2011, three-quarters of all cholera cases in africa occurred in inland regions. such outbreaks are either influenced by rainfall and subsequent floods or by drought- and water-induced stress. their concurrence with global cl ...201324101645
cholera outbreak in south africa, 2008-2009: laboratory analysis of vibrio cholerae o1 strains.a total of 720 vibrio cholerae o1 strains were recovered for investigation from an outbreak of cholera in south africa between november 2008 and april 2009.201324101643
the role of vibrio cholerae genotyping in africa.toxigenic vibrio cholerae, the causative agent of the disease cholera, is prevalent in the african continent from the 1970s when the seventh pandemic spread from asia to africa. in the past decade, cholera has caused devastating outbreaks in much of africa, illustrated by the recent cholera epidemics in zimbabwe and regions of central africa. given the extent of cholera in africa, a robust and efficient surveillance system should be in place to prevent and control the disease in this continent. ...201324101642
diagnosis of vibrio cholerae o1 infection in africa.isolation of vibrio cholerae o1 is necessary for cholera outbreak confirmation. rapid diagnostic testing of fecal specimens, based on lipopolysaccharide detection of v. cholerae o1 or o139, may assist in early outbreak detection and surveillance. cary-blair transport medium is recommended for specimen transport. filter paper, although used in epidemics, needs evaluation against rectal swab specimens. fecal specimens are subcultured onto selective and nonselective media, including 5% blood agar a ...201324101641
national surveillance data on the epidemiology of cholera in togo.togo is a cholera-endemic country bordered by other countries where this disease is endemic. we describe the epidemiology of cholera in togo, using national surveillance data.201324101639
cholera epidemiology in mozambique using national surveillance data.mozambique has experienced cholera for several decades. this study was undertaken to evaluate epidemiologic patterns to assist in guiding public health interventions.201324101638
potential for inhibition of bacterial efflux pumps in multidrug-resistant vibrio cholera. 201324135170
mapping the glycation sites in the neoglycoconjugate from hexasaccharide antigen of vibrio cholerae, serotype ogawa and the recombinant tetanus toxin c-fragment carrier.we report herein the glycation sites in a vaccine candidate for cholera formed by conjugation of the synthetic hexasaccharide fragment of the o-specific polysaccharide of vibrio cholerae, serotype ogawa, to the recombinant tetanus toxin c-fragment (rtt-hc) carrier. matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis of the vaccine revealed that it is composed of a mixture of neoglycoconjugates with carbohydrate : protein ratios of 1.9 : 1, 3.0 : 1, 4.0 : 1, 4.9  ...201324130011
emergence of vibrio cholerae o1 classical biotype in 2012 in iran.cholera outbreaks annually occur in many parts of iran. the aim of this study was to investigate the biotype and genotype diversity of v. cholerae isolates from recent outbreak (2012) in iran and to characterize the ctxb allelic sequence of isolates. the ctxb sequence of all isolates was analyzed and compared with the reference ctxb sequences for el tor and classical biotypes in genbank database. the pfge genotype specification of isolates was determined and genetic relatedness among isolates an ...201424117836
sodium-coupled dicarboxylate and citrate transporters from the slc13 family.the slc13 family in humans and other mammals consists of sodium-coupled transporters for anionic substrates: three transporters for dicarboxylates/citrate and two transporters for sulfate. this review will focus on the di- and tricarboxylate transporters: nadc1 (slc13a2), nadc3 (slc13a3), and nact (slc13a5). the substrates of these transporters are metabolic intermediates of the citric acid cycle, including citrate, succinate, and α-ketoglutarate, which can exert signaling effects through specif ...201424114175
seroepidemiologic survey of epidemic cholera in haiti to assess spectrum of illness and risk factors for severe disease.to assess the spectrum of illness from toxigenic vibrio cholerae o1 and risk factors for severe cholera in haiti, we conducted a cross-sectional survey in a rural commune with more than 21,000 residents. during march 22-april 6, 2011, we interviewed 2,622 residents ≥ 2 years of age and tested serum specimens from 2,527 (96%) participants for vibriocidal and antibodies against cholera toxin; 18% of participants reported a cholera diagnosis, 39% had vibriocidal titers ≥ 320, and 64% had vibriocida ...201324106192
laboratory-confirmed cholera and rotavirus among patients with acute diarrhea in four hospitals in haiti, 2012-2013.an outbreak of cholera began in haiti in october of 2010. to understand the progression of epidemic cholera in haiti, in april of 2012, we initiated laboratory-enhanced surveillance for diarrheal disease in four haitian hospitals in three departments. at each site, we sampled up to 10 hospitalized patients each week with acute watery diarrhea. we tested 1,616 specimens collected from april 2, 2012 to march 28, 2013; 1,030 (63.7%) specimens yielded vibrio cholerae, 13 (0.8%) specimens yielded shi ...201324106190
modeling the effect of water, sanitation, and hygiene and oral cholera vaccine implementation in haiti.in 2010, toxigenic vibrio cholerae was newly introduced to haiti. because resources are limited, decision-makers need to understand the effect of different preventive interventions. we built a static model to estimate the potential number of cholera cases averted through improvements in coverage in water, sanitation and hygiene (wash) (i.e., latrines, point-of-use chlorination, and piped water), oral cholera vaccine (ocv), or a combination of both. we allowed indirect effects and non-linear rela ...201324106189
discovery and biological characterization of the auromomycin chromophore as an inhibitor of biofilm formation in vibrio cholerae.bacterial biofilms pose a significant challenge in clinical environments due to their inherent lack of susceptibility to antibiotic treatment. it is widely recognized that most pathogenic bacterial strains in the clinical setting persist in the biofilm state, and are the root cause of many recrudescent infections. the discovery and development of compounds capable of either inhibiting biofilm formation or initiating biofilm dispersal might provide new therapeutic avenues for reducing the number ...201324106077
haitian variant ctxb producing vibrio cholerae o1 with reduced susceptibility to ciprofloxacin is persistent in yavatmal, maharashtra, india, after causing a cholera outbreak.vibrio cholerae o1 biotype el tor producing haitian variant cholera toxin (hct) and showing reduced susceptibility to ciprofloxacin caused a cholera outbreak associated with a high case fatality rate (4.5) in india. hct-secreting strains responsible for severe cholera epidemics in orissa (india), western africa and haiti were associated with increased mortality. there is a pressing need for an integrated multidisciplinary approach to combat further spread of newly emerging variant strains. the t ...201424102849
cryo-electron microscopy reveals the membrane insertion mechanism of v. cholerae hemolysin.vibrio cholerae hemolysin (hlya) is a 65 kda pore-forming toxin which causes lysis of target eukaryotic cells by forming heptameric channels in the plasma membrane. deletion of the 15 kda c-terminus β-prism carbohydrate-binding domain generates a 50 kda truncated variant (hlya50) with 1000-fold-reduced pore-forming activity. previously, we showed by cryo-electron microscopy that the two toxin oligomers have central channels, but the 65 kda toxin oligomer is a seven-fold symmetric structure with ...201424102290
role of the vibrio cholerae matrix protein bap1 in cross-resistance to antimicrobial peptides.outer membrane vesicles (omvs) that are released from gram-negative pathogenic bacteria can serve as vehicles for the translocation of effectors involved in infectious processes. in this study we have investigated the role of omvs of the vibrio cholerae o1 el tor a1552 strain in resistance to antimicrobial peptides (amps). to assess this potential role, we grew v. cholerae with sub-lethal concentrations of polymyxin b (pmb) or the amp ll-37 and analyzed the omvs produced and their effects on amp ...201324098113
vibrio cholerae porin ompu induces pro-inflammatory responses, but down-regulates lps-mediated effects in raw 264.7, thp-1 and human pbmcs.vibrio cholerae porin ompu plays a crucial role in the survival of the organism in the human gut. various observations suggest critical involvement of ompu in v. cholerae pathogenesis. however, ompu is poorly characterized in terms of its ability to evoke cellular responses, particularly in the context of host immune system. therefore, towards characterizing v. cholerae ompu for its host immunomodulatory functions, we have studied the ability of ompu to elicit pro-inflammatory responses in a ran ...201324086753
synergistic effect of various virulence factors leading to high toxicity of environmental v. cholerae non-o1/ non-o139 isolates lacking ctx gene : comparative study with clinical strains.vibrio cholerae non-o1/ non-o139 serogroups have been reported to cause sporadic diarrhoea in humans. cholera toxins have been mostly implicated for hypersecretion of ions and water into the small intestine. though most of the v. cholerae non-o1/ non-o139 strains lack these cholera toxins, several other innate virulence factors contribute towards their pathogenicity. the environmental isolates may thus act as reservoirs for potential spreading of these virulence genes in the natural environment ...201324086707
structural evaluation of gm1-related carbohydrate-cholera toxin interactions through surface plasmon resonance kinetic analysis.surface plasmon resonance (spr) can provide kinetic information about an interaction, and it can also be used to rapidly monitor dynamic processes, such as adsorption and degradation, without the need for sample labeling. here, we employed spr to analyze carbohydrate-protein interactions, particularly gm1-related carbohydrate-vibrio cholera toxin interactions. the interaction between cholera toxin subunits a (ctxa) and b (ctxb) was similar to general ligand-receptor interactions. after the direc ...201324081216
no evidence of significant levels of toxigenic v. cholerae o1 in the haitian aquatic environment during the 2012 rainy season.on october 21, 2010, haiti was struck by a cholera epidemic for the first time in over a century. epidemiological and molecular genetic data have clearly demonstrated that the bacterium was imported. nevertheless, the persistence of the epidemic for more than two years, the high incidence rates in some coastal areas and the seasonal exacerbations of the epidemic during the rainy seasons have prompted us to examine the levels of toxigenic vibrio cholerae in the haitian aquatic environment.201324077904
cholera epidemiology in zambia from 2000 to 2010: implications for improving cholera prevention and control strategies in the country.to review the cholera epidemiology in zambia from 2000 to 2010 in order to highlight the key lessons learned. based on our findings, we make recommendations for improving cholera prevention and control in country.201326862642
[genetic characterization of toxigenic vibrio cholerae non-o1/non-o139 strains, isolated in the middle asia].here, we report the characterization of 22 clinical toxigenic v. cholerae non-o1/non-o139 strains isolated in the middle asia (uzbekistan) in 1971-1990. pcr analysis has revealed that these strains contain the main virulence genes such as ctxa, zot, ace (ctxφ); rstc (rs1φ); tcpa, toxt, alda (pathogenicity island vpi), but they lack both pandemic islands vsp-i and vsp-ii specific to epidemic strains of o1 serogroup of el tor biotype and o139 serogroup. only two of the twenty two toxigenic strains ...201325508672
[genetic characterization of toxigenic vibrio cholerae non-o1/non-o139 strains, isolated in the middle asia].here, we report the characterization of 22 clinical toxigenic v. cholerae non-o1/non-o139 strains isolated in the middle asia (uzbekistan) in 1971-1990. pcr analysis has revealed that these strains contain the main virulence genes such as ctxa, zot, ace (ctxφ); rstc (rs1φ); tcpa, toxt, alda (pathogenicity island vpi), but they lack both pandemic islands vsp-i and vsp-ii specific to epidemic strains of o1 serogroup of el tor biotype and o139 serogroup. only two of the twenty two toxigenic strains ...201325474893
a study on the geophylogeny of clinical and environmental vibrio cholerae in kenya.cholera remains a significant public health challenge in many sub-saharan countries including kenya. we have performed a combination of phylogenetic and phenotypic analysis based on whole genome dna sequences derived from 40 environmental and 57 clinical v. cholerae from different regions of kenya isolated between 2005 and 2010. some environmental and all clinical isolates mapped back onto wave three of the monophyletic seventh pandemic v. cholerae el tor phylogeny but other environmental isolat ...201324066154
evaluation of monoclonal antibody based immunochromatographic strip test for direct detection of vibrio cholerae o1 contamination in seafood samples.a strip test for the detection of vibrio cholerae o1 was developed using two monoclonal antibodies (mabs), vc-223 and vc-1226, specific to the lipopolysaccharides of vibrio cholerae o1 inaba and ogawa serovars. the sensitivity of the test was 5 × 10(5)cfu/ml which was similar to that of dot blot test. the detection limit could be improved to 1cfu/ml of the original bacterial content after pre-incubation of the bacterium in alkaline peptone water (apw) for 12h. detection of v. cholerae o1 in vari ...201324060694
a novel 8-nm protein cage formed by vibrio cholerae acylphosphatase.here we show the formation of an ~8-nm cage formed by the self-assembly of acylphosphatase from vibrio cholerae o395 (vc-acp). the 12-subunit cage structure forms spontaneously and is stabilized through binding of sulfate ions at its exterior face and interfacial regions. crystal structure and studies in solutions illuminate the basis for the formation of the cage, while a single (cys20→arg) mutation (vc-acp-c20r) transforms vc-acp to a potent enzyme but disrupts the assembly into a trimer.201424055378
vibrio cholerae o1 el tor and o139 bengal strains carrying ctxb(et), bangladesh. 201324050113
development of a 5-minute rapid test for detecting vibrio cholerae o139.vibrio cholerae o139 is an etiology of cholera in thailand. we determined to prepare a rapid test to detect v cholerae o139 using an immunochromatographic method to be used for surveillance and use in community laboratories. we conjugated murine monoclonal antibodies specific to the lipopolysaccharide of v. cholerae o139 with colloidal gold particles. the sensitivity of the test was determined using 10-fold dilutions of v. cholerae o139. the lowest number of bacterial cells detected by the test ...201324050076
non-o1, non-o139 vibrio cholerae sepsis in a patient with nephrotic syndrome.non-o1, non-o139 vibrio cholerae is an encapsulated bacterium, ubiquitous in the marine environment and generally considered to be non-pathogenic. however, it is known to cause diarrheal illness, wound infection, and bacteremia in immunocompromised hosts. here we have describe non-o1, non-o139 v. cholerae sepsis in a patient with nephrotic syndrome following exposure to sea-water. interestingly, the exposure occurred remotely 4 months prior to the onset of nephrotic syndrome. the occurrence of f ...201324049279
shellfish-acquired vibrio cholerae cellulitis and sepsis from a vulnerable leg.the following case concerns a soft tissue vibrio cholerae (v. cholerae) infection in a fisherman who cut his foot while retrieving his fishing dinghy. it is rare for v. cholerae to cause extraintestinal infection. this v. cholera was identified as a non-toxigenic organism. the patient was successfully treated with medical therapy at waikato hospital (hamilton, new zealand) and discharged home after 10 days.201324045356
vibrio cholerae evades neutrophil extracellular traps by the activity of two extracellular nucleases.the gram negative bacterium vibrio cholerae is the causative agent of the secretory diarrheal disease cholera, which has traditionally been classified as a noninflammatory disease. however, several recent reports suggest that a v. cholerae infection induces an inflammatory response in the gastrointestinal tract indicated by recruitment of innate immune cells and increase of inflammatory cytokines. in this study, we describe a colonization defect of a double extracellular nuclease v. cholerae mut ...201324039581
cholera toxin disrupts barrier function by inhibiting exocyst-mediated trafficking of host proteins to intestinal cell junctions.cholera toxin (ct), a virulence factor elaborated by vibrio cholerae, is sufficient to induce the severe diarrhea characteristic of cholera. the enzymatic moiety of ct (ctxa) increases camp synthesis in intestinal epithelial cells, leading to chloride ion (cl(-)) efflux through the cftr cl(-) channel. to preserve electroneutrality and osmotic balance, sodium ions and water also flow into the intestinal lumen via a paracellular route. we find that ctxa-driven camp increase also inhibits rab11/exo ...201324034615
cholera toxin notches epithelial junctions.cholera toxin (ct) is the factor responsible for watery diarrhea associated with vibrio cholerae infection. in this issue, guichard et al. (2013) report that ct compromises intestinal epithelium barrier function via cyclic amp (camp)-induced disruption of rab11- and exocyst-dependent delivery of endocytic recycling cargo to cell-cell junctions.201324034608
aspartic acid 397 in subunit b of the na+-pumping nadh:quinone oxidoreductase from vibrio cholerae forms part of a sodium-binding site, is involved in cation selectivity, and affects cation-binding site cooperativity.the na(+)-pumping nadh:quinone complex is found in vibrio cholerae and other marine and pathogenic bacteria. nadh:ubiquinone oxidoreductase oxidizes nadh and reduces ubiquinone, using the free energy released by this reaction to pump sodium ions across the cell membrane. in a previous report, a conserved aspartic acid residue in the nqrb subunit at position 397, located in the cytosolic face of this protein, was proposed to be involved in the capture of sodium. here, we studied the role of this ...201324030824
detection of vibrio parahaemolyticus, vibrio vulnificus and vibrio cholerae with respect to seasonal fluctuations in temperature and plankton abundance.over a 1-year period, bi-monthly estuarine surface water and plankton samples (63-200 and > 200 μm fractions) were assayed by polymerase chain reaction for the prevalence of total vibrio parahaemolyticus, v. vulnificus and v. cholerae and select genes associated with clinical strains found in each species. neither temperature nor plankton abundance was a significant correlate of total v. parahaemolyticus; however, the prevalence of genes commonly associated with clinical strains (trh, tdh, orf8) ...201424024909
concurrent outbreaks of cholera and peripheral neuropathy associated with high mortality among persons internally displaced by a volcanic eruption.in october 2004, manam island volcano in papua new guinea erupted, causing over 10 000 villagers to flee to internally displaced person (idp) camps, including 550 from dugulaba village. following violence over land access in march 2010, the idps fled the camps, and four months later concurrent outbreaks of acute watery diarrhea and unusual neurological complaints were reported in this population.201324023752
deciphering the origins and tracking the evolution of cholera epidemics with whole-genome-based molecular epidemiology.the devastating haitian cholera outbreak that began in october 2010 is the first known cholera epidemic in this island nation. epidemiological and genomic data have provided strong evidence that united nations security forces from nepal introduced toxigenic vibrio cholerae o1, the cause of epidemic cholera, to haiti shortly before the outbreak arose. however, some have contended that indigenous v. cholerae contributed to the outbreak. in a recent paper (mbio 4:e00398-13, 2013), l. s. katz et al. ...201324023387
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