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[screening of harmine tolerance/degrading bacteria from camel rumen].peganum harmala, a famous traditional chinese drug, contains a variety of alkaloids and toxic for many animals. camels mainly live in desert or semi-desert areas, with the robust gastrointestine system in digesting various feed including toxic plants without disease symptoms.201020931866
viable but nonculturable state of foodborne pathogens in grapefruit juice: a study of laboratory.several foodborne human pathogens, when exposed to harsh conditions, enter viable but nonculturable (vbnc) state; however, still open is the question whether vbnc pathogens could be a risk for public health, because, potentially, they can resuscitate. moreover, cultural methods for food safety control were not able to detect vbnc forms of foodborne bacteria. particularly, it has not been established whether food chemophysical characteristics can induce vbnc state in contaminating pathogen bacter ...201020932087
shigella deploy multiple countermeasures against host innate immune responses.although the intestinal epithelium is equipped with multiple defense systems that sense bacterial components, transmit alarms to the immune system, clear the bacteria, and renew the injured epithelial lining, mucosal bacterial pathogens are capable of efficiently colonizing the intestinal epithelium, because they have evolved systems that modulate the inflammatory and immune responses of the host and exploit the harmful environments as replicative niches. in this review we highlight current topi ...201020934372
domains of the shigella flexneri type iii secretion system ipab protein involved in secretion regulation.type iii secretion systems (t3sss) are key determinants of virulence in many gram-negative bacterial pathogens. upon cell contact, they inject effector proteins directly into eukaryotic cells through a needle protruding from the bacterial surface. host cell sensing occurs through a distal needle "tip complex," but how this occurs is not understood. the tip complex of quiescent needles is composed of ipad, which is topped by ipab. physical contact with host cells initiates secretion and leads to ...201020937761
combination of two separate binding domains defines stoichiometry between type iii secretion system chaperone ipgc and translocator protein ipab.type iii secretion systems (ttsss) utilized by enteropathogenic bacteria require the presence of small, acidic virulence-associated chaperones for effective host cell infection. we adopted a combination of biochemical and cellular techniques to define the chaperone binding domains (cbds) in the translocators ipab and ipac associated with the chaperone ipgc from shigella flexneri. we identified a novel cbd in ipab and furthermore precisely mapped the boundaries of the cbds in both translocator pr ...201020937829
characterization and antimicrobial activity of 4-(β-d-glucopyranosyl-1→4-α-l-rhamnopyranosyloxy)-benzyl thiocarboxamide; a novel bioactive compound from moringa oleifera seed extract.antimicrobial activity of crude seed extract of moringa oleifera was investigated by thin layer chromatography bioassay against escherichia coli, pseudomonas aeruginosa, staphylococcus aureus, cladosporium cladosporioides, and penicillium sclerotigenum; most of them were prominently inhibited by an isolate with r(f) 0.92-0.96. characterization and identification of the extract revealed the occurrence of three bioactive compounds: 4-(α-l-rhamnopyranosyloxy)benzyl isothiocyanate, methyl n-4-(α-l-r ...201020941575
expression of bacterial virulence factors and cytokines during in vitro macrophage infection by enteroinvasive escherichia coli and shigella flexneri: a comparative study.enteroinvasive escherichia coli (eiec) and shigella spp cause bacillary dysentery in humans by invading and multiplying within epithelial cells of the colonic mucosa. although eiec and shigella share many genetic and biochemical similarities, the illness caused by shigella is more severe. thus, genomic and structure-function molecular studies on the biological interactions of these invasive enterobacteria with eukaryotic cells have focused on shigella rather than eiec. here we comparatively stud ...201020944993
an fda bioinformatics tool for microbial genomics research on molecular characterization of bacterial foodborne pathogens using microarrays.advances in microbial genomics and bioinformatics are offering greater insights into the emergence and spread of foodborne pathogens in outbreak scenarios. the food and drug administration (fda) has developed a genomics tool, arraytrack™, which provides extensive functionalities to manage, analyze, and interpret genomic data for mammalian species. arraytrack™ has been widely adopted by the research community and used for pharmacogenomics data review in the fda's voluntary genomics data submissio ...201020946615
integron types, gene cassettes, antimicrobial resistance genes and plasmids of shigella sonnei isolates from outbreaks and sporadic cases in taiwan.this study analysed the presence, location and transferability of integrons and antibiotic resistance genes in 103 shigella sonnei outbreak isolates and in 32 sporadic isolates from taiwan. multiple antimicrobial resistance was common in both outbreak (95 %) and sporadic (97 %) isolates. class 1 integrons were present in 34 outbreak isolates (33 %) and in six sporadic isolates (19 %). this study is the first, to our knowledge, to identify an atypical sul3-associated class 1 integron carrying the ...201020947666
rapid multiple-locus variable-number tandem-repeats analysis of shigella spp. using multicolour capillary electrophoresis.the multiple-locus variable-number tandem-repeats analysis (mlva) method for genotyping has proven to be a fast and reliable typing tool in several bacterial species. mlva is in our laboratory the routine typing method for salmonella enterica subsp. enterica serovar typhimurium, escherichia coli (two assays), listeria monocytogenes and yersinia enterocolitica. the gram-negative invasive enteropathogenic bacterium shigella is the most common cause of bacillary dysentery (shigellosis) worldwide, a ...201020951171
surveillance of shigellosis by real-time pcr suggests underestimation of shigellosis prevalence by culture-based methods in a population of rural china.shigellosis is a leading public health issue in china, especially in children under 5 years of age. the disease burden of shigellosis is usually underestimated by conventional culture. in this study, real-time pcr was applied to detect shigella infection in parallel with routine culture, to investigate the true burden of disease caused by shigella spp.201020951728
subtype prevalence, plasmid profiles and growing fluoroquinolone resistance in shigella from kolkata, india (2001-2007): a hospital-based study.shigellosis is a major public health problem, and increasing antimicrobial resistance has complicated its treatment. we report isolation frequency, plasmid profiles and antimicrobial resistance of shigella subtypes in kolkata, india, from a prospective hospital-based study.201020955371
sensitization of microcin j25-resistant strains by a membrane-permeabilizing peptide.microcin j25 (mccj25) is a plasmid-encoded, 21-amino-acid, antibacterial peptide produced by escherichia coli. mccj25 inhibits rna polymerase and the membrane respiratory chain. mccj25 uptake into e. coli-sensitive strains is mediated by the outer membrane receptor fhua and the inner membrane proteins tonb, exbb, exbd, and sbma. this peptide is active on some e. coli, salmonella, and shigella species strains, while other gram-negative bacteria, such as clinical isolates of enterobacter cloacae, ...201020802073
an outbreak of shigellosis due to shigella flexneri serotype 3a in a prison in iran.on june 16 and 17, 2007, the medical clinic of a prison in isfahan, iran received multiple reports of gastrointestinal illness among prisoners. a cross-sectional study was therefore undertaken to determine the extent, causative agent and possible source of the outbreak.201020804308
mutagenesis and chemical cross-linking suggest that wzz dimer stability and oligomerization affect lipopolysaccharide o-antigen modal chain length control.in shigella flexneri, the polysaccharide copolymerase (pcp) protein wzz(sf) confers a modal length of 10 to 17 repeat units (rus) to the o-antigen (oag) component of lipopolysaccharide (lps). pcps form oligomeric structures believed to be related to their function. to identify functionally important regions within wzz(sf), random in-frame linker mutagenesis was used to create mutants with 5-amino-acid insertions (termed wzz(i) proteins), and dna sequencing was used to locate the insertions. anal ...201020453100
carbon metabolism of intracellular bacterial pathogens and possible links to virulence.new technologies such as high-throughput methods and 13c-isotopologue-profiling analysis are beginning to provide us with insight into the in vivo metabolism of microorganisms, especially in the host cell compartments that are colonized by intracellular bacterial pathogens. in this review, we discuss the recent progress made in determining the major carbon sources and metabolic pathways used by model intracellular bacterial pathogens that replicate either in the cytosol or in vacuoles of infecte ...201020453875
acid stress response in enteropathogenic gammaproteobacteria: an aptitude for survival.enteric bacteria such as escherichia coli have acquired a wide array of acid stress response systems to counteract the extreme acidity encountered when invading the host's digestive or urinary tracts. these acid stress response systems are both enzyme and chaperone based. the 3 main enzyme-based acid resistance pathways are glutamate-, arginine-, and lysine-decarboxylase pathways. they are under a complex regulatory network allowing the bacteria to fine tune its response to the external environm ...201020453931
antioxidant, antibacterial and antigiardial activities of walsura robusta roxb.walsura robusta roxb. (family: meliaceae) is a well-known multi-purpose medicinal plant, and has been employed for a wide range of disease conditions without documented scientific data. in the current study, four pure isolated compounds, 3,4,5-trimethoxyphenyl beta-d-glucopyranoside (1), turpinionoside a (2), (+)-lyoniresinol 3alpha-o-beta-d-glucopyranoside (3) and (-)-lyoniresinol 3alpha-o-beta-d-glucopyranoside (4), were isolated from the leaves and twigs of w. robusta. biological evaluation f ...201020461627
detection of airborne bacteria in a german turkey house by cultivation-based and molecular methods.today's large-scale poultry production with densely stocked and enclosed production buildings is often accompanied by very high concentrations of airborne microorganisms leading to a clear health hazard for employees working in such environments. depending on the expected exposure to microorganisms, work has to be performed under occupational safety conditions. in this study, turkey houses bioaerosols were investigated by cultivation-based and molecular methods in parallel to determine the conce ...201020720091
uncivil engineers: chlamydia, salmonella and shigella alter cytoskeleton architecture to invade epithelial cells.the obligate intracellular bacterial pathogen chlamydia trachomatis is a major cause of blindness and sexually transmitted diseases. like the enteric pathogens salmonella and shigella, chlamydia injects effector proteins into epithelial cells to initiate extensive remodeling of the actin cytoskeleton at the bacterial attachment site, which culminates in the engulfment of the bacterium by plasma membrane extensions. numerous salmonella and shigella effectors promote this remodeling by activating ...201020722600
serum neopterin is elevated in patients infected with shigella.abstract:201020727206
lactoferrin increases both resistance to salmonella typhimurium infection and the production of antibodies in mice.lactoferrin (lf) is a multifunctional iron-binding glycoprotein with antibacterial and immunomodulatory activities. the antibacterial influence of orally administered bovine lf (blf) against murine infection caused by salmonella typhimurium (s. typhimurium) has scarcely been explored. in the current study, balb/c mice were treated orally for 7 days with either 5 or 100mg of bovine lactoferrin (blf). on day 7 of treatment, mice were intragastrically infected with a lethal or sublethal dose of col ...201020727369
medicinal potions used against infectious bowel diseases in mayan traditional medicine.since one of the main health problems of the indigenous population are infectious bowel diseases, we decided to test mayan medicinal potions used to treat these conditions against some of the causal agents.201020728517
[dysentery and amoebiasis in poland in 2008].the number as well as incidence rate of notified as shigellosis, bacillary dysentery cases in xxi century are every year lower. only 33 cases were notified in the year 2008 (incidence rate 0.09/100 000 population), while the 64 cases were notified in 2007 (incidence rate 0.17/100 000), but 35 (incidence rate 0.09) were notified in 2006 and median in the 2002-2006 years was 75 cases, incidence rate 0.2/100 000 population. since 2000 no one-death case was notified. several imported cases were noti ...201020731222
pad4 is essential for antibacterial innate immunity mediated by neutrophil extracellular traps.neutrophils trap and kill bacteria by forming highly decondensed chromatin structures, termed neutrophil extracellular traps (nets). we previously reported that histone hypercitrullination catalyzed by peptidylarginine deiminase 4 (pad4) correlates with chromatin decondensation during net formation. however, the role of pad4 in net-mediated bacterial trapping and killing has not been tested. here, we use pad4 knockout mice to show that pad4 is essential for net-mediated antibacterial function. u ...201020733033
structures of the o-antigens of escherichia coli o13, o129, and o135 related to the o-antigens of shigella flexneri.o-polysaccharides (o-antigens) were isolated from escherichia coli o13, o129, and o135 and studied by chemical analyses along with 2d (1)h and (13)c nmr spectroscopy. they were found to possess a common -->2)-l-rha-(alpha1-->2)-l-rha-(alpha1-->3)-l-rha-(alpha1-->3)-d-glcnac-(beta1--> backbone, which is a characteristic structural motif of the o-polysaccharides of shigella flexneri types 1-5. in both the bacterial species, the backbone is decorated with lateral glucose residues or/and o-acetyl gr ...201020546712
agap2 regulates retrograde transport between early endosomes and the tgn.the retrograde transport route links early endosomes and the tgn. several endogenous and exogenous cargo proteins use this pathway, one of which is the well-explored bacterial shiga toxin. adp-ribosylation factors (arfs) are approximately 20 kda gtp-binding proteins that are required for protein traffic at the level of the golgi complex and early endosomes. in this study, we expressed mutants and protein fragments that bind to arf-gtp to show that arf1, but not arf6 is required for transport of ...201020551179
host factors required for modulation of phagosome biogenesis and proliferation of francisella tularensis within the cytosol.francisella tularensis is a highly infectious facultative intracellular bacterium that can be transmitted between mammals by arthropod vectors. similar to many other intracellular bacteria that replicate within the cytosol, such as listeria, shigella, burkholderia, and rickettsia, the virulence of f. tularensis depends on its ability to modulate biogenesis of its phagosome and to escape into the host cell cytosol where it proliferates. recent studies have identified the f. tularensis genes requi ...201020552012
generation of chitin-derived oligosaccharides toxic to pathogenic bacteria using chia74, an endochitinase native to bacillus thuringiensis.to demonstrate that an endochitinase (chia74) native to bacillus thuringiensis can be used to generate chitin-derived oligosaccharides (ogs) with antibacterial activity against a number of aetiological agents of disease, including bacteria that cause diarrhoeal and emetic syndromes in humans.201020557451
development of a serogroup-specific multiplex pcr assay to detect a set of escherichia coli serogroups based on the identification of their o-antigen gene clusters.the escherichia coli serogroups o115, o126, o137, o158, o165, and o173 are pathogenic strains associated with diarrhea. molecular approaches such as pcr have been proven to be rapid, inexpensive, and accurate. the sequences of the o-antigen-processing genes wzx and wzy are specific for different o antigens and are generally used as the target genes for the detection and identification of e. coli strains belonging to different o serogroups. in this report, the o-antigen gene clusters of these 6 o ...201020561581
frequency and antimicrobial susceptibility of shigella species isolated in children medical center hospital, tehran, iran, 2001-2006.appropriate antimicrobial treatment of shigellosis depends on identifying its changing resistance pattern over time. we evaluated 15,255 stool culture submitted from july 2001 to june 2006 to the laboratory of children medical center hospital. specimen culture, bacterial identification, and disk diffusion susceptibility testing were performed according to national committee for clinical laboratory standards guidelines. from 15,255 stool samples, 682 (4.5%) were positive for shigella species. the ...201020563441
microarray analysis of shigella flexneri-infected epithelial cells identifies host factors important for apoptosis inhibition.shigella flexneri inhibits apoptosis in infected epithelial cells. in order to understand the pro-survival effects induced by the bacteria, we utilized apoptosis-specific microarrays to analyze the changes in eukaryotic gene expression in both infected and uninfected cells in the presence and absence of staurosporine, a chemical inducer of the intrinsic pathway of apoptosis. the goal of this research was to identify host factors that contribute to apoptosis inhibition in infected cells.201020429941
bacteriological and parasitological assessment of food handlers in the omdurman area of sudan.pathogenic organisms are thought to be widely distributed among food handlers. this study was designed to assess the prevalence of carriers of some pathogenic bacteria and intestinal parasites among food handlers in the city of omdurman, sudan.201020434126
a multiplex pcr method to detect 14 escherichia coli serogroups associated with urinary tract infections.urinary tract infections (utis) are one of the most common bacterial infections and are predominantly caused by uropathogenic escherichia coli (upec). e. coli strains belonging to 14 serogroups, including o1, o2, o4, o6, o7, o8, o15, o16, o18, o21, o22, o25, o75 and o83, are the most frequently detected upec strains in a diverse range of clinical urine specimens. in the current study, the o-antigen gene clusters of e. coli serogroups o1, o2, o18 and o75 were characterized. a multiplex pcr method ...201020434495
modulation of shigella virulence in response to available oxygen in vivo.bacteria coordinate expression of virulence determinants in response to localized microenvironments in their hosts. here we show that shigella flexneri, which causes dysentery, encounters varying oxygen concentrations in the gastrointestinal tract, which govern activity of its type three secretion system (t3ss). the t3ss is essential for cell invasion and virulence. in anaerobic environments (for example, the gastrointestinal tract lumen), shigella is primed for invasion and expresses extended t ...201020436458
microbial community on healthy and diseased leaves of an invasive plant eupatorium adenophorum in southwest china.invasive plants have caused great economic losses and environmental problems worldwide. eupatorium adenophorum is one of the most invasive weeds in china. to better understand its invasive mechanisms, in the present paper, the microbial communities of healthy and diseased leaves of e. adenophorum were obtained using both culture-independent and -dependent methods and their diversities were compared. the bacteria obtained from culture-independent method belong to proteobacteria (95.8%), actinobac ...201020437143
phenotypic characterization and genomic analysis of the shigella sonnei bacteriophage sp18.a novel bacteriophage that infects shigella sonnei was isolated from the gap river in korea, and its phenotypic and genomic characteristics were investigated. the virus, called sp18, showed morphology characteristic of the family myoviridae, and phylogenetic analysis of major capsid gene (gp23) sequences classified it as a t4-like phage. based on host spectrum analysis, it is lytic to s. sonnei, but not to shigella flexneri, shigella boydii or members of the genera escherichia and salmonella. py ...201020437154
antimicrobial resistance patterns and characterization of integrons of shigella sonnei isolates in seoul, 1999-2008.a total of 66 shigella sonnei isolates from 1999 to 2008 in seoul was analyzed for their antimicrobial resistance, carriage of integron, and the patterns of pulsed-field gel electrophoresis (pfge). a high level of antimicrobial resistance to streptomycin (100%), trimethoprim/sulfamethoxazole (95%), tetracycline (94%), nalidixic acid (65%), and ampicillin (41%) was observed among s. sonnei isolates. fourteen profiles of antimicrobial resistance were identified with the most common resistance prof ...201020437157
antimicrobial resistance trends of shigella serotypes in new york city, 2006-2009.shigellosis is the third most common enteric bacterial infection in the united states. although infection is typically self-limiting, empiric treatment is often prescribed. because of increasing antimicrobial resistance to shigella, empiric treatment options are decreasing. identifying resistance patterns can inform empiric treatment recommendations. the goals of our study were to examine risk factors associated with antimicrobial resistance of shigella and examine issues related to empiric trea ...201020438349
high prevalence of trimethoprim-resistance cassettes in class 1 and 2 integrons in senegalese shigella spp isolates.integrons have a well-established role in the dissemination of resistance among gram-negative pathogens and are thus a useful marker of antibiotic resistance. shigellae are noteworthy for their multiple drug resistance, having gradually acquired resistance to most widely use and inexpensive antimicrobial drugs.201020440057
genome-wide analysis of the h-ns and sfh regulatory networks in salmonella typhimurium identifies a plasmid-encoded transcription silencing mechanism.the conjugative inchi1 plasmid psfr27 from shigella flexneri 2a strain 2457t encodes the sfh protein, a paralogue of the global transcriptional repressor h-ns. sfh allows psfr27 to be transmitted to new bacterial hosts with minimal impact on host fitness, providing a 'stealth' function whose molecular mechanism has yet to be determined. the impact of the sfh protein on the salmonella enterica serovar typhimurium transcriptome was assessed and binding sites for sfh in the salmonella typhimurium g ...201020444106
the role of sura factor in outer membrane protein transport and virulence.the escherichia coli periplasmic chaperone and peptidyl-prolyl isomerase (ppiase) sura is a major factor in the biogenesis of β-barrel outer membrane proteins (omps) and as such plays an integral role in cell envelope homeostasis and cell envelope functions. recently, the biological importance of sura was further substantiated by the finding that sura also affects pathogenicity, being required for full virulence of uropathogenic escherichia coli, salmonella, and shigella spp. moreover, given the ...201020447864
the type iii effectors nlee and nleb from enteropathogenic e. coli and ospz from shigella block nuclear translocation of nf-kappab p65.many bacterial pathogens utilize a type iii secretion system to deliver multiple effector proteins into host cells. here we found that the type iii effectors, nlee from enteropathogenic e. coli (epec) and ospz from shigella, blocked translocation of the p65 subunit of the transcription factor, nf-kappab, to the host cell nucleus. nf-kappab inhibition by nlee was associated with decreased il-8 expression in epec-infected intestinal epithelial cells. ectopically expressed nlee also blocked nuclear ...201020485572
[traveler's diarrhea, the most common health problem of travelers].bacteria cause 50 to 80% of travelers' diarrheic diseases. the most important pathogens include enterotoxigenic escherichia coli (etec), campylobacteria, salmonellae and shigella. diarrheic viruses cause 5 to 25% and protozoa less than 10% of travelers' diarrheas. hand and food hygiene constitute the main preventive measures. treatment of traveler's diarrhea is based on rehydration therapy and rest. antimicrobial therapy is required only in cases with exceptionally severe symptoms.201020486490
violations identified from routine swimming pool inspections--selected states and counties, united states, 2008.swimming is the third most popular u.s. sport or exercise activity, with approximately 314 million visits to recreational water venues, including treated venues (e.g., pools), each year. the most frequently reported type of recreational water illness (rwi) outbreak is gastroenteritis, the incidence of which is increasing. during 1997--2006, chlorine- and bromine-susceptible pathogens (e.g., shigella and norovirus) caused 24 (23%) of 104 treated venue--associated rwi outbreaks of gastroenteritis, ...201020489681
battle and balance at mucosal surfaces--the story of shigella and antimicrobial peptides.shigella is a major cause of morbidity and mortality for children in many developing countries. emergence of antibiotic-resistance among shigella demands the development of effective medicines. antimicrobial peptides (amps) are expressed in phagocytes and at epithelial surfaces and are important effector molecules of innate immunity. we have found that pathogens are able to turn off the endogenous expression of amps, resulting in serious infections such as shigellosis. a therapeutic rationale to ...201020494122
regulation of high-affinity iron acquisition homologues in the tsetse fly symbiont sodalis glossinidius.sodalis glossinidius is a facultative intracellular bacterium that is a secondary symbiont of the tsetse fly (diptera: glossinidae). since studies with other facultative intracellular bacteria have shown that high-affinity iron acquisition genes are upregulated in vivo, we investigated the regulation of several sodalis genes that encode putative iron acquisition systems. these genes, sg1538 (hemt) and sg1516 (sita), are homologous to genes encoding periplasmic heme and iron/manganese transporter ...201020494987
antiviral and anti-inflammatory diterpenoids from the soft coral sinularia gyrosa.chemical investigation of the soft coral sinularia gyrosa led to the purification of three new diterpenoids, designated as gyrosanols a-c (1-3). the structures of 1-3 were elucidated through extensive spectroscopic analyses. compounds 1 and 2 exhibited antiviral activity against hcmv with ic(50)'s of 2.6 and 3.7 microm, respectively. in addition, compounds 1 and 2 showed significant anti-inflammatory activity by reducing the levels of the cox-2 protein (19.6 + or - 3.9% and 29.1 + or - 9.6%, res ...201020499851
foodborne illness: is it on the rise?foodborne illness is a serious public health threat. the centers for disease control and prevention (cdc) estimates that 76 million foodborne illnesses, including 325,000 hospitalizations and 5,000 deaths, occur in the united states each year. two recently published foodborne diseases active surveillance network (foodnet) reports showed that salmonella, campylobacter, shigella, cryptosporidium, and shiga toxin escherichia coli (stec) o157 continue to be leading causes of both the number and inci ...201020500787
[antibacterial activity of recombinant thanatin expressed by e.coli er2566].to express antibacterial peptide thanatin in the prokaryotic expression system and test its antibacterial activity.201020501392
the 33 carboxyl-terminal residues of spa40 orchestrate the multi-step assembly process of the type iii secretion needle complex in shigella flexneri.the type iii secretion apparatus (t3sa) is a central virulence factor of many gram-negative bacteria. its overall morphology consists of a cytoplasmic region, inner- and outer-membrane sections and an extracellular needle. in shigella, the length of the needle is regulated by spa32. to understand better the role of spa32 we searched for its interacting partners using a two-hybrid screen in yeast. we found that spa32 interacts with the 33 c-terminal residues (cc*) of spa40, a member of the conser ...201020507885
induction of specific cd8 t cells against intracellular bacteria by cd8 t-cell-oriented immunization approaches.for protection against intracellular bacteria such as mycobacterium tuberculosis and listeria monocytogenes, the cellular arm of adaptive immunity is necessary. a variety of immunization methods have been evaluated and are reported to induce specific cd8(+) t cells against intracellular bacterial infection. modified bcg vaccines have been examined to enhance cd8(+) t-cell responses. naked dna vaccination is a promising strategy to induce cd8(+) t cells. in addition to this strategy, live attenua ...201020508818
[analysis on bacillary dysentery surveillance data collected from the national surveillance system in 2007.].to improve the national surveillance plan on bacillary dysentery and to increase the sensitivity of the surveillance system on the disease.201020510059
["autophagy and microorganisms": hotspots of a mini-symposium]. 201020510155
establishment of specific pathogen-free macaque colonies in tsukuba primate research center of japan for aids research.cynomolgus monkeys have been maintained in indoor facilities as closed colony monkeys in tsukuba primate research center in japan since 1978. several microorganisms, including bacteria, parasites and viruses, were eliminated from the cynomolgus monkeys in this colony of tprc. various kinds of viruses (b virus, measles virus, simian varicella virus, simian immunodeficiency virus, simian t cell leukemia virus, simian d type retrovirus, simian cytomegalovirus, simian epstein-barr virus, and simian ...201020510748
isolation of bacteriocin-like substances producing bacteria from finished cattle-manure compost and activity evaluation against some food-borne pathogenic and spoilage bacteria.a finished compost sample was examined for bacteriocin-like substance production against five pathogenic bacteria: salmonella typhimurium ef 85-9, escherichia coli o157:h7 atcc 43888, enterococcus faecalis jcm 8726, staphylococcus aureus jcm 2151, and yersinia enterocolitica jcm 7577. at the preliminary detection of bacterial strains exhibiting antimicrobial activity from the compost sample, thirteen strains could be isolated. screening of the inhibitory activity was done using agar-well diffusi ...201020513963
emergence of fluoroquinolone resistance in shigella isolated from andaman & nicobar islands, india. 201020516546
crystallization and preliminary crystallographic studies of corc, a magnesium-ion transporter.corc is a magnesium transporter that is involved in the mg(2+)-efflux function of the cora transporter system, an mg(2+) channel, from shigella flexneri. native corc was purified and crystallized in the native form and in a ligand-free form and diffraction data sets were collected to 2.9 and 3.4 a resolution, respectively. the native corc crystals belonged to space group p2(1)2(1)2(1), with unit-cell parameters a = 64.31, b = 74.44, c = 132.78 a. the ligand-free corc crystals belonged to space g ...201020516599
three-hour molecular detection of campylobacter, salmonella, yersinia, and shigella species in feces with accuracy as high as that of culture.campylobacter jejuni and salmonella, shigella, and yersinia species (along with shiga toxin-producing escherichia coli) are the most common causes of acute bacterial diarrheal disease in the united states. current detection techniques are time-consuming, limiting usefulness for patient care. we developed and validated a panel of rapid pcr assays for the detection and identification of c. jejuni, c. coli, salmonella, and yersinia species and shigella and enteroinvasive e. coli in stool samples. a ...201020519461
emerging trends in the etiology of enteric pathogens as evidenced from an active surveillance of hospitalized diarrhoeal patients in kolkata, india.abstract:201020525383
frequency of viral, bacterial and parasitic enteropathogens among young children with acute diarrhoea in saudi arabia.the frequency of viral, bacterial and parasitic enteropathogens among 270 paediatric patients (< 5 years of age) in various hospitals of makkah and jeddah cities of saudi arabia were investigated.201020527643
prevalence of enterotoxins among escherichia coli isolates causing bacteraemia.the most frequent cause of bacteraemia among gram-negative bacteria is escherichia coli. analysis of the genes encoding the shigella enterotoxin 1 (shet-1), shet-2, enteroaggregative heat stable toxin 1 (east-1) toxins and aggr factor in e. coli strains causing bacteraemia revealed that set1 genes were presented significantly more frequently among quinolone-susceptible strains (p<0.0001), in phylogenetic group b2 (p=0.0004) and in biofilm strains (p=0.02). in contrast, sen genes were significant ...201020529132
a novel anti-virulence gene revealed by proteomic analysis in shigella flexneri 2a.abstract:201020540790
immunochemical studies of shigella flexneri 2a and 6, and shigella dysenteriae type 1 o-specific polysaccharide-core fragments and their protein conjugates as vaccine candidates.there is no licensed vaccine for the prevention of shigellosis. our approach to the development of a shigella vaccines is based on inducing serum igg antibodies to the o-specific polysaccharide (o-sp) domain of their lipopolysaccharides (lps). we have shown that low molecular mass o-sp-core (o-spc) fragments isolated from shigella sonnei lps conjugated to proteins induced significantly higher antibody levels in mice than the full length o-sp conjugates. this finding is now extended to the o-spc ...201020542498
protein refolding is required for assembly of the type three secretion needle.pathogenic gram-negative bacteria use a type three secretion system (ttss) to deliver virulence factors into host cells. although the order in which proteins incorporate into the growing ttss is well described, the underlying assembly mechanisms are still unclear. here we show that the ttss needle protomer refolds spontaneously to extend the needle from the distal end. we developed a functional mutant of the needle protomer from shigella flexneri and salmonella typhimurium to study its assembly ...201020543831
an epidemiologic review of enteropathogens in gaborone, botswana: shifting patterns of resistance in an hiv endemic region.the epidemiology of diarrheal disease in botswana, an hiv endemic region, is largely unknown. our primary objective was to characterize the prevalent bacterial and parasitic enteropathogens in gaborone, botswana. secondary objectives included determining corresponding antimicrobial resistance patterns and the value of stool white and red blood cells for predicting bacterial and parasitic enteropathogens.201020543877
the sudden dominance of blactx-m harbouring plasmids in shigella spp. circulating in southern vietnam.plasmid mediated antimicrobial resistance in the enterobacteriaceae is a global problem. the rise of ctx-m class extended spectrum beta lactamases (esbls) has been well documented in industrialized countries. vietnam is representative of a typical transitional middle income country where the spectrum of infectious diseases combined with the spread of drug resistance is shifting and bringing new healthcare challenges.201020544028
a soluble form of the pilus protein fima targets the vdac-hexokinase complex at mitochondria to suppress host cell apoptosis.inhibition of apoptotic response of host cells during an early phase of infection is a strategy used by many enteroinvasive bacterial pathogens to enhance their survival. here, we report the identification of a soluble form of the pilus protein fima from the culture supernatants of e. coli k1, salmonella, and shigella that can potently inhibit bax-mediated release of cytochrome c from isolated mitochondria. similar to the infected cells, hct116 cells stably expressing fima display a delay in the ...201020347420
34 kda momp of shigella flexneri promotes tlr2 mediated macrophage activation with the engagement of nf-kappab and p38 map kinase signaling.the 34 kda major outer membrane protein (momp) of shigella flexneri 2a induces combinatorial expression of tlr2 and tlr6 on peritoneal macrophages of balb/c mice. between the two best-characterized tlrs, to date, tlr2 and tlr4, which are chiefly responsible for recognizing majority of bacterial products, tlr2 alone participates in recognition of 34 kda momp. in addition to tlrs, momp enhances the mrna expression of myd88 and traf6 and induces the nuclear translocation of nf-kappab as well as act ...201020347487
long-term downregulation of protease-activated receptor-2 expression in distal colon in rats following bacillary dysentery.the aim of this study was to determine changes of par-2 expression in distal colon and the sensitivity of colonic muscle to sligrl-nh2, the par-2-activating peptide (par-2-ap) following bacillary dysentery. shigella flexneri was administrated intragastrically in healthy male rats to induce bacillary dysentery. the effect of sligrl-nh2 on the motility of colonic muscle strips were examined. the expression of par-2 was determined by immunohistochemistry and western blotting. intragastric administr ...201020347884
antibiotics for the treatment of dysentery in children.ciprofloxacin, ceftriaxone and pivmecillinam are the antibiotics currently recommended by the world health organization (who) for the treatment of dysentery in children; yet there have been no reviews of the clinical effectiveness of these antibiotics in recent years.201020348130
global transcriptional response of macrophage-like thp-1 cells to shiga toxin type 1.shiga toxins (stxs) are bacterial cytotoxins produced by the enteric pathogens shigella dysenteriae serotype 1 and some serotypes of escherichia coli that cause bacillary dysentery and hemorrhagic colitis, respectively. to date, approaches to studying the capacity of stxs to alter gene expression in intoxicated cells have been limited to individual genes. however, it is known that many of the signaling pathways activated by stxs regulate the expression of multiple genes in mammalian cells. to ex ...201020351145
isolation and selection of coliphages as potential biocontrol agents of enterohemorrhagic and shiga toxin-producing e. coli (ehec and stec) in cattle.to isolate, characterize and select phages as potential biocontrol agents of enterohemorrhagic and shiga toxin-producing escherichia coli (ehec and stec) in cattle.201020353429
molecular architecture of the mn2+-dependent lactonase ulag reveals an rnase-like metallo-beta-lactamase fold and a novel quaternary structure.the ulag gene, located in the ula regulon, is crucial for the catabolism of l-ascorbate under anaerobic conditions and it has been proposed to encode for the putative l-ascorbate-6-p lactonase. the ulag gene is widespread among eubacteria, including human commensal and pathogenic genera such as escherichia, shigella, klebsiella and salmonella. here, we report the three-dimensional structures of the apoenzyme and mn(2+) holoenzyme of ulag from e. coli to 2.6 a resolution, determined using single- ...201020359483
modeling fimbriae mediated parasite-host interactions.type 1 fimbriae are a known virulence factor in a number of pathogenic enterobacteriaceae, including salmonella, shigella and e. coli. yet, they are also expressed by some commensal strains, notably of e. coli. one hypothesis of the role of fimbriae in commensals is that they evoke a small but tolerable host immune response in order to have the host release sialic acid, which is a valuable nutrient. genetic evidence suggests that sialic acid down-regulates fimbriation. this has been believed to ...201020359486
structure of shigella ipgb2 in complex with human rhoa: implications for the mechanism of bacterial guanine nucleotide exchange factor mimicry.a common theme in bacterial pathogenesis is the manipulation of eukaryotic cells by targeting the cytoskeleton. this is in most cases achieved either by modifying actin, or indirectly via activation of key regulators controlling actin dynamics such as rho-gtpases. a novel group of bacterial virulence factors termed the wxxxe family has emerged as guanine nucleotide exchange factors (gefs) for these gtpases. the precise mechanism of nucleotide exchange, however, has remained unclear. here we repo ...201020363740
isolation of bacteria from mouse caecal samples and description of bacteroides sartorii sp. nov.caecal samples from wild-type and tnf(deltaare) mice were cultured on selective media containing bile salts, amino acids or casein macro-peptides. twenty-two strains were isolated and identified by 16s rrna gene sequencing. twenty-one strains showed >98% similarity to known bacteria (blautia spp., clostridium innocuum, enterococcus spp., escherichia coli, lactobacillus murinus, parabacteroides goldsteinii and shigella dysenteriae). one additional isolate, strain a-c2-0, was a new bacterium. the ...201020369227
antibacterial effect of the bioactive compound beauvericin produced by fusarium proliferatum on solid medium of wheat.to obtain the bioactive compound beauvericin (bea), fusarium proliferatum cect 20569 was grown on a solid medium of wheat, utilizing the technique of the solid state fermentation (ssf), being this mycotoxin purified by high performance liquid chromatography (hplc) with a reverse phase semi-preparative column using as the mobile phase acetonitrile/water in gradient condition. the purity of the bea was verified by analytical hplc and liquid chromatography tandem mass spectrometry (lc/ms-ms). the p ...201020371252
the effects of a vegetable-derived probiotic lactic acid bacterium on the immune response.the objective of this study was to investigate the probiotic properties of the fermented vegetable derived lactic acid bacterium, l. plantarum. l. plantarum 10hk2 showed antibacterial activity against pathogenic bacteria and immunomodulating effects on murine macrophage cell lines. raw 264.7 cells stimulated with viable cells of this probiotic strain increased the amounts of pro-inflammatory mediators such as il-1beta, il-6 and tnf-alpha, as well as the anti-inflammatory mediator, il-10. icr mic ...201020377751
use of optical mapping to sort uropathogenic escherichia coli strains into distinct subgroups.optical maps were generated for 33 uropathogenic escherichia coli (upec) isolates. for individual genomes, the ncoi restriction fragments aligned into a unique chromosome map for each individual isolate, which was then compared with the in silico restriction maps of all of the sequenced e. coli and shigella strains. all of the upec isolates clustered separately from the shigella strains as well as the laboratory and enterohaemorrhagic e. coli strains. moreover, the individual strains appeared to ...201020378655
biological potentials and cytotoxicity of various extracts from endemic origanum minutiflorum o. schwarz & p.h. davis.the aim of the present study was to investigate antioxidative, antimicrobial and cytotoxic effects of endemic origanum minutiflorum (o. schwarz & p.h. davis). antioxidant activities of the extracts from o. minutiflorum were evaluated by using dpph radical scavenging, beta-carotene bleaching and metal chelating activity assays. in addition, the amounts of total phenol components in the plant extracts were determined. in the beta-carotene bleaching test, the extracts exhibited in the range of 58.1 ...201020381570
preliminary foodnet data on the incidence of infection with pathogens transmitted commonly through food - 10 states, 2009.the foodborne diseases active surveillance network (foodnet) of cdc's emerging infections program conducts active, population-based surveillance in 10 u.s. states for all laboratory-confirmed infections with select enteric pathogens transmitted commonly through food. this report describes preliminary surveillance data for 2009 and trends in incidence since 1996. in 2009, a total of 17,468 laboratory-confirmed cases of infection were identified. in comparison with the first 3 years of surveillanc ...201020395935
nmr characterization of the interaction of the salmonella type iii secretion system protein sipd and bile salts.salmonella and shigella bacteria require the type iii secretion system (t3ss) to inject virulence proteins into their hosts and initiate infections. the tip proteins sipd and ipad are critical components of the salmonella and shigella t3ss, respectively. recently, sipd and ipad have been shown to interact with bile salts, which are enriched in the intestines, and are hypothesized to act as environmental sensors for these enteric pathogens. bile salts activate the shigella t3ss but repress the sa ...201020397637
innate ifn-gamma production by subsets of natural killer cells, natural killer t cells and gammadelta t cells in response to dying bacterial-infected macrophages.interferon-gamma (ifn-gamma) activation of macrophages is a crucial step in the early innate defence against bacterial infection. this innate ifn-gamma is thought to be produced mainly by natural killer (nk) cells through activation with interleukin (il)-12p70 secreted by macrophages and dendritic cells (dcs) that have sensed bacterial products. however, a number of reports have shown that bacterial stimuli are unable to induce macrophages and/or dcs to produce sufficient amounts of il-12p70 unl ...201020415785
production and immunogenicity of recombinant ferric enterobactin protein (fepa).ferric siderophore complexes are produced by most bacteria to acquire iron, a vital element. these complexes are transported across the outer membrane by receptor proteins commonly known as fepa (ferric enterobactin protein). in this study we attempted to evaluate the immunogenicity of the membrane protein fepa, aiming at inhibition of iron uptake to protect invasion of the host by the bacterium.201020418143
tracking the secretion of fluorescently labeled type iii effectors from single bacteria in real time.a large number of gram negative pathogens use a specialized needle-like molecular machine known as type iii secretion (t3s) system. this highly sophisticated molecular device consists of a basal body spanning the two bacterial membranes and a protruding needle structure that is connected to a distal translocator complex. the main features of the t3s system are (i) activation after host cellular membrane contact and (ii) the ability to "inject" effectors into host cells through the needle apparat ...201020419414
shigella-associated diarrhea in children in south jakarta, indonesia.a surveillance of shigella infections was conducted on 612 children aged 0-12 years-old presenting with diarrhea to mampang and tebet community health centers in south jakarta, indonesia, during february 2005 through september 2007. shigella was isolated from 9.3% of diarrhea patients in the health centers. s.flexneri which was found in 5.9% of patients, and was the most frequent species isolated, comprising 63.2% (36/57) of all shigella species isolated. shigella species were found significantl ...201020578526
newer insights into the mechanism of action of psidium guajava l. leaves in infectious diarrhoea.psidium guajava l., myrtaceae, is used widely in traditional medicine for the treatment of diarrhoea, dysentery, gastroenteritis, stomachaches, and indigestion. however, the effect of the leaf extract of p. guajava on the pathogenesis of infectious diarrhoea has not been studied. the present study evaluates the effect of a hot aqueous extract (decoction) of dried leaves of p. guajava on parameters associated with pathogenicity of infectious diarrhoea. the aim was to understand its possible mecha ...201020584265
a pathoadaptive deletion in an enteroaggregative escherichia coli outbreak strain enhances virulence in a caenorhabditis elegans model.enteroaggregative escherichia coli (eaec) strains are important diarrheal pathogens. eaec strains are defined by their characteristic stacked-brick pattern of adherence to epithelial cells but show heterogeneous virulence and have different combinations of adhesin and toxin genes. pathoadaptive deletions in the lysine decarboxylase (cad) genes have been noted among hypervirulent e. coli subtypes of shigella and enterohemorrhagic e. coli. to test the hypothesis that cad deletions might account fo ...201020584976
bacterial pathogens associated with bloody diarrhea in uruguayan children.diarrheal disease continues to be a serious health problem, especially in developing countries. bloody diarrhea represents approximately 20-30% of all cases and has higher morbidity and mortality. treatment with antibiotics is beneficial in cases of shigella, campylobacter, yersinia and salmonella infection, principally in those children with a higher risk of invasive disease. the aims of this study were to detect the bacterial agents associated with bloody diarrhea in children and to determine ...201020589332
progressivemauve: multiple genome alignment with gene gain, loss and rearrangement.multiple genome alignment remains a challenging problem. effects of recombination including rearrangement, segmental duplication, gain, and loss can create a mosaic pattern of homology even among closely related organisms.201020593022
cladophora in the great lakes: impacts on beach water quality and human health.cladophora in the great lakes grows rapidly during the warm summer months, detaches, and becomes free-floating mats as a result of environmental conditions, eventually becoming stranded on recreational beaches. cladophora provides protection and nutrients, which allow enteric bacteria such as escherichia coli, enterococci, shigella, campylobacter, and salmonella to persist and potentially regrow in the presence of the algae. as a result of wind and wave action, these microorganisms can detach an ...201020595755
probiotic administration effect on fecal mutagenicity and microflora in the goat's gut.the application of potentially beneficial microorganisms to increase host defense is a new trend to increase health benefits. in this paper the first specific host probiotics for goats from a mixture isolated from healthy animals (lactobacillus reuteri ddl 19, lactobacillus alimentarius ddl 48, enterococcus faecium dde 39 and bifidobacterium bifidum ddba) was assayed. the effect of probiotic oral administration on goats' weight, gut microbiota, as well as on the production of mutagen compounds a ...201020598940
escape of intracellular shigella from autophagy requires binding to cholesterol through the type iii effector, icsb.type iii secretion systems are present in many pathogenic bacteria and mediate the translocation of bacterial effectors into host cells. identification of host targets of these effectors is crucial for understanding bacterial virulence. icsb, a type iii secretion effector, helps shigella to evade the host autophagy defense system by binding to the autophagy protein, atg5. here, we show that icsb is able to interact specifically with cholesterol. the cholesterol binding domain (cbd) of icsb is lo ...201020599519
enterocyte-like caco-2 cells as a model for in vitro studies of diarrhoeagenic providencia alcalifaciens invasion.the entry of providencia alcalifaciens into the enterocyte-like cell line caco-2 compared to hep-2 was studied. of the 22 p. alcalifaciens strains, 13 and 21 were invasive for caco-2 and hep-2 cells, respectively. in contrast to hep-2 cells, p. alcalifaciens was internalised by caco-2 cells via receptor-mediated endocytosis. tyrosine kinases play an important role in p. alcalifaciens uptake, also microfilaments and microtubules are engaged in this process. inhibition of endosome acidification by ...201020600792
inhibition of shigella sonnei adherence to ht-29 cells by lactobacilli from chinese fermented food and preliminary characterization of s-layer protein involvement.in this study, seven lactobacilli with a high degree of antagonistic activity against three pathogens and good adherence to ht-29 cells were selected. the ability of these seven lactobacilli to inhibit adhesion of shigella sonnei to intestinal mucosa was studied on cultured ht-29 cells. lactobacilli were added simultaneously with, before or after s. sonnei to test for their effectiveness in exclusion, competition and displacement assays, respectively. lactobacillus paracasei subp. paracasei m5-l ...201020600857
microbial contamination of raw meat and its environment in retail shops in karachi, pakistan.this study was conducted to examine the frequency of contamination in retail meat available in karachi, pakistan.201020601790
isoprenoid metabolism as a therapeutic target in gram-negative pathogens.gram-negative enterobacteria include a variety of human pathogens, perhaps most notably e. coli, salmonella, shigella, yersinia, and proteus. while there are treatment options for the diseases caused by these organisms, multi-drug resistance is often a problem and development of novel antibiotics has lagged over recent years. in humans, the isoprenoid biosynthetic pathway has become a subject of intense research for therapeutic modulation of human enzymes in diseases including hypercholesterolem ...201020615187
methods for monitoring trends in the incidence of foodborne diseases: foodborne diseases active surveillance network 1996-2008.foodborne illnesses are a substantial health burden in the united states. the foodborne diseases active surveillance network (foodnet) is the principal foodborne disease component of the centers for disease control and prevention's emerging infections program. foodnet is a collaborative project among centers for disease control and prevention, emerging infections program sites, the u.s. department of agriculture, and the u.s. food and drug administration. one of foodnet's main objectives is to m ...201020617933
safety and immunogenicity of a shigella flexneri 2a invaplex 50 intranasal vaccine in adult volunteers.shigellosis is a leading cause of diarrhea worldwide prompting vaccine development. the shigella flexneri invaplex 50 is a macromolecular complex containing ipab, ipac, and lps, formulated from an aqueous extract of virulent shigella delivered via nasal administration. preclinical vaccine testing demonstrated safety, immunogenicity and efficacy. an open-label dose-escalating phase 1 study evaluated a 3-dose (2-week intervals) regimen via nasal pipette delivery. thirty-two subjects were enrolled ...201020619378
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