Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| identification of novel genomic islands associated with small rnas. | genome evolution in prokaryotes is assisted by integration of gene pools from phages and plasmids. regions downstream of trnas and tmrnas are considered as hot spots for the integration of these gene pools or genomic islands. till date, genomic islands have been identified only at trna/tmrna genes in the enterobacterial genomes. present work reports 10 distinct small rnas as potent integration sites for genomic islands. a known tool trnacc 1.0 has been used to identify genomic islands associated ... | 2007 | 18467773 |
| [the pathogens responsible for waterborne infections: the biological risk for agricultural laborer]. | the presence of microbiological agents in waters intended for human consumption, irrigation and recreational activity, is a significant risk for the human health. recent epidemiological data demonstrate an increase of the diseases caused by waterborne pathogens, especially of the gastroenteritis infections, in the industrialized countries. numerous studies have evidenced the contamination of deep and surface waters; bacteria within contaminated water represent a highly diversified group, that ar ... | 2007 | 18409935 |
| campylobacter reactive arthritis: a systematic review. | to review the literature on the epidemiology of campylobacter-associated reactive arthritis (rea). | 2007 | 17360026 |
| shigella sonnei bacteremia: two adult cases and review of the literature. | shigella sonnei bacteremia in adult patients is rare. we present 2 cases from our center, and 7 others from the literature are reviewed in detail. diabetes mellitus and malignancy are frequent predisposing conditions. despite severe illness at presentation, our patients achieved good outcomes with prompt initiation of antimicrobial therapy. | 2007 | 17366038 |
| the type iii secretion system needle tip complex mediates host cell sensing and translocon insertion. | type iii secretion systems (t3sss) are essential virulence determinants of many gram-negative bacterial pathogens. the shigella t3ss consists of a cytoplasmic bulb, a transmembrane region and a hollow 'needle' protruding from the bacterial surface. physical contact with host cells initiates secretion and leads to assembly of a pore, formed by ipab and ipac, in the host cell membrane, through which proteins that facilitate host cell invasion are translocated. as the needle is implicated in host c ... | 2007 | 17367391 |
| elimination by ozone of shigella sonnei in shredded lettuce and water. | several outbreaks of shigellosis have been attributed to the consumption of contaminated fresh-cut vegetables. the minimal processing of these products make it difficult to ensure that fresh produce is safe for consumer. chlorine-based agents have been often used to sanitize produce and reduce microbial populations in water applied during processing operations. however, the limited efficacy of chlorine-based agents and the production of chlorinated organic compounds with potential carcinogenic a ... | 2007 | 17367682 |
| low molecular weight proteins of outer membrane of salmonella typhimurium are immunogenic in salmonella induced reactive arthritis revealed by proteomics. | in patients with reactive arthritis (rea)/undifferentiated spondyloarthropathy (uspa), synovial fluid mononuclear cells (sfmc) show proliferation to bacterial antigens that trigger rea, i.e. chlamydia, yersinia, campylobactor, shigella and salmonella species. we have shown previously that sfmc proliferate significantly to outer membrane proteins of s typhimurium in salmonella induced rea. in the present study we characterized the immunoreactive fractions of outer membrane protein (omp) of s typh ... | 2007 | 17376200 |
| inactivation of foodborne pathogens using a one atmosphere uniform glow discharge plasma. | this study was conducted to determine the efficacy of a one atmosphere uniform glow discharge plasma (oaugdp) for inactivation of foodborne pathogens and to evaluate the influence of growth temperature, ph, and culture age on their inactivation. escherichia coli o157:h7, listeria monocytogenes, staphylococcus aureus, bacillus cereus, salmonella enteritidis, vibrio parahaemolyticus, yersinia enterocolitica, and shigella flexneri were evaluated. three-strain mixtures of each bacterium were inocula ... | 2007 | 17378708 |
| antimicrobial activity of bacillus subtilis and bacillus pumilus during the fermentation of african locust bean (parkia biglobosa) for soumbala production. | to examine predominant isolates of bacillus subtilis and b. pumilus isolated from soumbala for their antimicrobial activity against indicator microorganisms as micrococcus luteus, staphyloccocus aureus, bacillus cereus, enterococus facium, listeria monocytogenes, escherichia coli, salmonella typhimurium, shigella dysenteriae, yersinia enterocolitica, aspergillus ochraceus and penicillium roqueforti. | 2007 | 17381739 |
| l-sorbose utilization by virulent escherichia coli and shigella: different metabolic adaptation of pathotypes. | the frequency of l-sorbose utilization differs significantly between pathotypes of escherichia coli and shigella from 93% to 0%. among 266 strains tested, this frequency increased in the order shigella, enterotoxigenic e. coli (etec), enteroinvasive e. coli (eiec), shiga toxin-producing e. coli (stec), enteroaggregative e. coli, enteropathogenic e. coli (epec), and neonatal bacterial meningitis (nbm) e. coli. this suggests an association of pathomechanism with the capability to degrade l-sorbose ... | 2007 | 17382590 |
| in vitro activity of garenoxacin tested against a worldwide collection of ciprofloxacin-susceptible and ciprofloxacin-resistant enterobacteriaceae strains (1999-2004). | garenoxacin is a novel des-f(6)-quinolone with a chemical structure that lacks the c6 position fluorine and has a unique difluoromethoxy substitution at position c8. this study evaluated the in vitro activity of garenoxacin tested against a large collection of enterobacteriaceae collected worldwide. the bacterial isolates were consecutively collected from more than 70 medical centers from bloodstream, respiratory, urinary tract, and skin and soft tissue infections. the isolates were tested again ... | 2007 | 17383140 |
| small rnas controlling iron metabolism. | iron is one of the most important metals in the metabolism of many organisms, including bacteria, in which it serves as a cofactor in multiple enzymatic reactions. most of the earlier research on iron regulation in bacteria has focused on the transcriptional regulator fur and its effect on the many genes involved in iron uptake. more recent work demonstrates the essential role of a small regulatory rna, ryhb, in iron metabolism. ryhb downregulates a large number of transcripts encoding iron-usin ... | 2007 | 17383226 |
| assessment and interpretation of bacterial viability by using the live/dead baclight kit in combination with flow cytometry. | the commercially available live/dead baclight kit is enjoying increased popularity among researchers in various fields of microbiology. its use in combination with flow cytometry brought up new questions about how to interpret live/dead staining results. intermediate states, normally difficult to detect with epifluorescence microscopy, are a common phenomenon when the assay is used in flow cytometry and still lack rationale. it is shown here that the application of propidium iodide in combinatio ... | 2007 | 17384309 |
| [molecular characterization of the strain causing a shigellosis outbreak in a madrid school]. | the aim of this study is to describe a shigella sonnei outbreak in a school. | 2007 | 17386220 |
| characterization of the outer membrane receptor shua from the heme uptake system of shigella dysenteriae. substrate specificity and identification of the heme protein ligands. | shigella dysenteriae, like many bacterial pathogens, has evolved outer membrane receptor-mediated pathways for the uptake and utilization of heme as an iron source. as a first step toward understanding the mechanism of heme uptake we have undertaken a site-directed mutagenesis, spectroscopic, and kinetic analysis of the outer membrane receptor shua of s. dysenteriae. purification of the outer membrane receptor gave a single band of molecular mass 73 kda on sds-page. initial spectroscopic analysi ... | 2007 | 17387178 |
| detecting low concentrations of shigella sonnei in environmental water samples by pcr. | outbreaks of shigella sonnei associated with contaminated water have been reported and methods for the simultaneous detection of shigellae and enteroinvasive escherichia coli in water samples have been developed with detection limits of 10(1)-10(2) cfu ml(-1) of water. because 10(1)-10(2)shigellae can cause disease, a more sensitive detection method as an addition to the existing methods for detection of shigella sonnei in water samples is reported here. initially, 33 shigella sonnei and 72 non- ... | 2007 | 17391373 |
| vitamin a deficiency in patients with diarrhea and hiv infection in ethiopia. | diarrhea, micronutrient deficiencies and hiv/aids are major public health problems in developing countries, especially in sub-saharan africa. this study was aimed to investigate serum levels of vitamin a in diarrheic patients with and without hiv co-infection compared to healthy controls. two hundred eleven diarrheic patients (110 hiv infected), 87 apparently healthy controls and 41 asymptomatic hiv seropositive blood donors who visited the university of gondar hospital, in gondar, ethiopia were ... | 2007 | 17392128 |
| structural relation of the antigenic polysaccharides of escherichia coli o40, shigella dysenteriae type 9, and e. coli k47. | o-polysaccharides were isolated from the lipopolysaccharides of escherichia coli o40 and shigella dysenteriae type 9 and studied by chemical analyses along with (1)h and (13)c nmr spectroscopy. the following new structure of the o-polysaccharide of e. coli o40 was established: -->2)-beta-d-galp-(1-->4)-beta-d-manp-(1-->4)-alpha-d-galp-(1-->3)-beta-d-glcpnac-(1--> theo-polysaccharide structure of s. dysenteriae type 9 established earlier was revised and found to be identical to the reported struc ... | 2007 | 17395169 |
| altered expression of muc2 and muc5ac in response to shigella infection, an in vivo study. | infection of mucosal epithelial cells by shigella species leads to an intense and acute inflammatory bowel disease that is characterized by watery diarrhea and purulent discharge. mucin production is a common defense mechanism to protect the underlying mucosa against pathogens. the molecular mechanism(s) underlying mucin induction is unknown in shigellosis. in this study, we have evaluated the relationship between shigella infection, the expression of muc2 and muc5ac and the participation of sig ... | 2007 | 17395379 |
| detection and identification of bacterial enteropathogens by polymerase chain reaction and conventional techniques in childhood acute gastroenteritis in gaza, palestine. | acute gastroenteritis and diarrhea are common and costly problems that cause significant morbidity and mortality in children worldwide. in palestine, diarrhea is one of the major causes of outpatient visits and hospitalizations. | 2007 | 17398132 |
| [shigellosis or bacillary dysentery]. | shigellosis, commonly known as bacillary dysentery, is an enterobacterial disease caused by the shigella genus, which now belongs to the escherichia tribe, because of their genetic and phenotypic similarities. s. sonnei, flexneri, boydii and dysenteriae differ in their epidemiologic and pathogenic characteristics. s. sonnei is predominant in industrialized countries and causes the mildest disease. s. dysentery is especially dangerous because it occurs in outbreaks, sometimes in catastrophic situ ... | 2007 | 17399943 |
| rotavirus disease in young children from hanoi, vietnam. | pathogen prevalences and antimicrobial susceptibilities are essential for the rational development of preventive strategies for diarrheal diseases, but little recent information from vietnam is available. we prospectively studied the prevalence of enteric pathogens in children less than 5 years of age with acute diarrhea and in nondiarrhea controls in a city hospital in hanoi, vietnam for 1 year. | 2007 | 17414396 |
| monitoring of pathogenicity of effluents from the uasb based sewage treatment plant. | the microbial profile of an upflow anaerobic sludge blanket reactor based sewage treatment plant located at a suburb of delhi, india, and possible risk due to the pathogenicity of the treated wastewater was investigated. frequency of occurrence of salmonella, shigella and vibrio was 100% at all the stages of sewage treatment. however, recovery of vibrio was the highest among all the pathogens. the order of removal of all the pathogens was same at the different stages of the treatment. ratio of c ... | 2007 | 17295111 |
| bile salts stimulate recruitment of ipab to the shigella flexneri surface, where it colocalizes with ipad at the tip of the type iii secretion needle. | shigella flexneri uses its type iii secretion apparatus (ttsa) to deliver invasins into human cells. this ttsa possesses an external needle with ipad at its tip. we now show that deoxycholate promotes the stable recruitment of ipab to the needle tip without inducing a rapid burst of type iii secretion. the maintenance of ipab at the needle tip requires a stable association of ipad with the shigella surface. this is the first demonstration of a translocator protein being stably associated with th ... | 2007 | 17296762 |
| survival of shigella sonnei on smooth tomato surfaces, in potato salad and in raw ground beef. | this study investigated the survival of a five-strain shigella sonnei cocktail on smooth tomato surfaces, in potato salad and in raw ground beef. all inocula were resistant to the antibiotic rifampicin to allow simple detection of the target culture among the indigenous microflora of the food samples. inoculated tomatoes were stored at 13 degrees c/85% relative humidity, the standard holding conditions for mature, green tomatoes. inoculated potato salad and ground beef samples were stored at 2.5 ... | 2007 | 17428565 |
| preliminary foodnet data on the incidence of infection with pathogens transmitted commonly through food--10 states, 2006. | foodborne illnesses are a substantial health burden in the united states. the foodborne diseases active surveillance network (foodnet) of cdc's emerging infections program collects data from 10 u.s. states regarding diseases caused by enteric pathogens transmitted commonly through food. foodnet quantifies and monitors the incidence of these infections by conducting active, population-based surveillance for laboratory-confirmed illnesses. this report describes preliminary surveillance data for 20 ... | 2007 | 17431379 |
| plasmid-mediated quinolone resistance determinant qnrs1 found in salmonella enterica strains isolated in the uk. | to determine the prevalence of qnr genes in selected salmonella enterica and escherichia coli isolated in the uk. | 2007 | 17434878 |
| ryhb, an iron-responsive small rna molecule, regulates shigella dysenteriae virulence. | regulation of bacterial gene expression by small rna (srna) molecules is an increasingly recognized phenomenon but one that is not yet fully understood. we show that the srna ryhb suppresses several virulence-associated phenotypes of shigella dysenteriae, a causative agent of bacillary dysentery in humans. the virulence genes repressed by s. dysenteriae ryhb include those encoding the type iii secretion apparatus, its secreted effectors, and specific chaperones. suppression of shigella virulence ... | 2007 | 17438026 |
| dipstick for rapid diagnosis of shigella flexneri 2a in stool. | shigellosis or bacillary dysentery, an acute bloody diarrhoea, is a major public health burden in developing countries. in the absence of prompt and appropriate treatment, the infection is often fatal, particularly in young malnourished children. here, we describe a new diagnostic test for rapid detection, in stool, at the bedside of patients, of shigella flexneri 2a, the most predominant agent of the endemic form of the disease. | 2007 | 17440606 |
| a novel serovar of shigella dysenteriae from patients with diarrhoea in bangladesh. | every year, around 3 % of isolates from patients with diarrhoea at dhaka hospital, icddr,b, are identified as shigella-like organisms (slos) based on their activity in biochemical tests. these isolates do not react with any of the current shigella antisera including all existing and provisional serotypes. among these slos, a unique cluster of seven isolates with an identical plasmid profile was found and these isolates were further characterized by phenotypic and genotypic techniques. all were n ... | 2007 | 17446289 |
| effect of intensive handwashing in the prevention of diarrhoeal illness among patients with aids: a randomized controlled study. | patients with aids frequently develop diarrhoeal illness. in this randomized, controlled study, 260 patients were screened for those who had not had diarrhoea in the preceding 3 months and who had received a stable highly active antiretroviral therapy regimen for at least 6 weeks prior to the study enrollment. a total of 148 patients met the inclusion criteria and were enrolled: 75 patients were randomly assigned to an intensive handwashing intervention (i.e. handwashing after defecation, after ... | 2007 | 17446290 |
| norovirus outbreak in a district general hospital--new strain identified. | media reports about norovirus outbreaks, especially in hospitals and nursing homes, have accumulated in the past years. the reasons for this increasing problem are manifold: resistance against common disinfectants, a high level of contagion (a dose of less than 100 particles may be infective); variability of the virus-genome documented by polymerase chain reaction-studies, as well as further factors concerning modern life-style. the following study describes and analyses a norovirus outbreak in ... | 2007 | 17299671 |
| evaluation of an enzyme immunoassay-based stool antigen test to detect campylobacter jejuni and campylobacter coli. | an enzyme immunoassay-based antigen test (ridascreen campylobacter; r-biopharm, darmstadt, germany) was evaluated for the detection of campylobacter jejuni and campylobacter coli in 1050 clinical stool samples as compared with culture on selective medium. after routine inoculation for salmonella, shigella, yersinia, aeromonas, plesiomonas, and campylobacter, the same swab specimens were used for the antigen test. the positivity rate for campylobacter was 9.3% in culture, and the antigen test gav ... | 2007 | 17300899 |
| the phosphothreonine lyase activity of a bacterial type iii effector family. | pathogenic bacteria use the type iii secretion system to deliver effector proteins into host cells to modulate the host signaling pathways. in this study, the shigella type iii effector ospf was shown to inactivate mitogen-activated protein kinases (mapks) [extracellular signal-regulated kinases 1 and 2 (erk1/2), c-jun n-terminal kinase, and p38]. ospf irreversibly removed phosphate groups from the phosphothreonine but not from the phosphotyrosine residue in the activation loop of mapks. mass sp ... | 2007 | 17303758 |
| yeast functional genomic screens lead to identification of a role for a bacterial effector in innate immunity regulation. | numerous bacterial pathogens manipulate host cell processes to promote infection and ultimately cause disease through the action of proteins that they directly inject into host cells. identification of the targets and molecular mechanisms of action used by these bacterial effector proteins is critical to understanding pathogenesis. we have developed a systems biological approach using the yeast saccharomyces cerevisiae that can expedite the identification of cellular processes targeted by bacter ... | 2007 | 17305427 |
| the role of the vacb gene in the pathogenesis of brucella abortus. | brucella species are important zoonotic pathogens affecting a wide variety of mammals. therefore, the identification of new brucella virulence factors is of great interest in understanding bacterial pathogenesis and immune evasion. in this study, we have identified brucella abortus vacb gene that presents 2343 nucleotides and 781 amino acids and it shows 39% identity with shigella flexneri vacb gene that encodes an exoribonuclease rnase r involved in bacterial virulence. further, we have inactiv ... | 2007 | 17306588 |
| h-ns antagonism in shigella flexneri by virb, a virulence gene transcription regulator that is closely related to plasmid partition factors. | the virb protein of shigella flexneri is a positive regulator of the major virulence operons of this enteroinvasive intracellular pathogen. virb resembles no other transcription factor but is strongly homologous to plasmid partition proteins. we found that the binding of the virb protein to the promoter region of the icsb virulence gene induced hypersensitivity to cleavage by dnase i over a region to which the h-ns repressor protein binds and completely abolished the protection of this sequence ... | 2007 | 17307842 |
| heme inhibits the dna binding properties of the cytoplasmic heme binding protein of shigella dysenteriae (shus). | heme uptake and utilization by pathogenic bacteria are critical for virulence and disease, since heme and heme proteins are a major source of iron within the host. although the role of outer membrane heme receptors in this process has been extensively characterized at the genetic and biochemical level, the role of the cytoplasmic heme binding proteins is not yet clear. the shigella dysenteriae cytoplasmic heme binding protein, shus, has previously been shown to promote utilization of heme as an ... | 2007 | 17323920 |
| conformational stability and differential structural analysis of lcrv, pcrv, bipd, and sipd from type iii secretion systems. | diverse gram-negative bacteria use type iii secretion systems (t3ss) to translocate effector proteins into the cytoplasm of eukaryotic cells. the type iii secretion apparatus (t3sa) consists of a basal body spanning both bacterial membranes and an external needle. a sensor protein lies at the needle tip to detect environmental signals that trigger type iii secretion. the shigella flexneri t3sa needle tip protein, invasion plasmid antigen d (ipad), possesses two independently folding domains in v ... | 2007 | 17327391 |
| a method for fast and simple detection of major diarrhoeagenic escherichia coli in the routine diagnostic laboratory. | a multiplex pcr was developed for the detection of the following genes characteristic of diarrhoeagenic escherichia coli (dec): verocytotoxins 1 (vtx1) and 2 (vtx2), characteristic of verocytotoxin-producing e. coli (vtec); intimin (eae), found in enteropathogenic e. coli (epec), attaching and effacing e. coli and vtec; heat-stable enterotoxin (esta) and heat-labile enterotoxin (elta), characteristic of enterotoxigenic e. coli (etec); and invasive plasmid antigen (ipah), characteristic of entero ... | 2007 | 17331124 |
| expression level of heterologous tat genes is crucial for in vivo reconstitution of a functional tat translocase in escherichia coli. | the tat system has the remarkable capacity of exporting proteins in folded conformation across the cytoplasmic membrane. the functional tat translocase from gram-negative bacteria consists of tata, tatb and tatc proteins. to gain information about the species specificity of the tat translocase, we cloned tat genes from gram-negative pathogens shigella flexneri 2a str. 301, vibrio cholerae el tor n16961, pseudomonas aeruginosa pao1, thermophilic sulfolobus solfataricus p2, thermus thermophilus hb ... | 2007 | 17336443 |
| shigella flexneri inhibits staurosporine-induced apoptosis in epithelial cells. | shigella flexneri is a facultative intracellular organism that causes bacillary dysentery. the shigella ipab protein activates caspase 1 in macrophages, which eventually leads to apoptosis. in contrast, epithelial cells infected with shigella undergo a stress response but do not die. therefore, the objective of this study was to determine if shigella has the ability to inhibit apoptosis in epithelial cells. a modified gentamicin protection assay was used to investigate if hela cells infected wit ... | 2007 | 17339354 |
| genetic characterization of the escherichia coli o66 antigen and functional identification of its wzy gene. | escherichia coli is a clonal species, and occurs as both commensal and pathogenic strains, which are normally classified on the basis of their o, h, and k antigens. the o-antigen (o-specific polysaccharide), which consists of a series of oligosaccharide (o-unit) repeats, contributes major antigenic variability to the cell surface. the o-antigen gene cluster of e. coli o66 was sequenced in this study. the genes putatively responsible for the biosynthesis of dtdp-6-deoxy-l-talose and gdp-mannose, ... | 2007 | 17342059 |
| rapid identification of escherichia coli safety and laboratory strain lineages based on multiplex-pcr. | escherichia coli k-12, b, c and w strains are the most frequently used bacterial safety and laboratory strains. lineage-specific dna fragments were detected by microplate subtractive hybridization and utilized to create a fast differentiation method using a single pcr reaction to differentiate clearly the four lineages and separate them from pathogenic variants. the method has been evaluated on a comprehensive selection of widely used laboratory strains and a variety of pathogenic e. coli repres ... | 2007 | 17343689 |
| [shigella flexneri modulates host cell epigenetic information as a strategy to shape the transcriptional response]. | 2007 | 17349276 | |
| luminex detection of fecal indicators in river samples, marine recreational water, and beach sand. | research to understand and remediate coastal pollution is moving toward a multitiered approach in which traditional enumeration of fecal indicators is accompanied by molecular analysis of a variety of targets. technology that rapidly detects multiple microbial contaminants would benefit from such an approach. the luminex 100 system is a suspension array that assays multiple analytes rapidly in a single well of a microtiter plate. the ability of the system to simultaneously detect multiple fecal ... | 2007 | 17350051 |
| characterization of sulphonamide resistance genes and class 1 integron gene cassettes in enterobacteriaceae, central african republic (car). | the aim of this study was to characterize genes encoding sulphonamide resistance and gene cassettes associated with class 1 integrons in trimethoprim-sulphamethoxazole resistant enterobacteriaceae recovered from bangui, central african republic (car). | 2007 | 17350987 |
| [risk of hospitalisation due to foodborne bacterial gastroenteritis--secondary publication]. | in a matched cohort study we estimate the risk of hospitalisation due to gastroenteritis, complications and sequelae after infections with zoonotic salmonella, campylobacter spp., yersinia enterocolitica, e. coli and shigella infections. out of 52,783 patients, 7,524 (14.4%) were hospitalized with gastroenteritis, 647 (1.2%) with complications and 865 (1.7%) with long-term sequelae. in denmark in 2005 there were 6,010 registered episodes of infections with bacteria that are usually foodborne, co ... | 2007 | 17355849 |
| extended-spectrum beta-lactamase-producing shigella strains in israel, 2000-2004. | routine susceptibility testing of 5,616 shigella isolates at the national shigella reference centre in israel over a 5-year period (2000-2004) revealed resistance to ceftriaxone in one strain of shigella boydii 2 and in two strains each of shigella flexneri 2a, s. flexneri 6, and shigella sonnei. all seven isolates were confirmed as producers of extended-spectrum beta-lactamase (esbl) by the combination disk method, the vitek 1 system, and a modification of the double-disk synergy test, which is ... | 2007 | 17265070 |
| epidemiological characterization of resistance and pcr typing of shigella flexneri and shigella sonnei strains isolated from bacillary dysentery cases in southeast brazil. | shigella spp are gram-negative, anaerobic facultative, non-motile, and non-sporulated bacilli of the enterobacteriaceae family responsible for "shigellosis" or bacillary dysentery, an important cause of worldwide morbidity and mortality. however, despite this, there are very few epidemiological studies about this bacterium in brazil. we studied the antibiotic resistance profiles and the clonal structure of 60 shigella strains (30 s. flexneri and 30 s. sonnei) isolated from shigellosis cases in d ... | 2007 | 17273662 |
| evaluation of the growth inhibitory activities of triphala against common bacterial isolates from hiv infected patients. | the isolation of microbial agents less susceptible to regular antibiotics and the rising trend in the recovery rates of resistant bacteria highlights the need for newer alternative principles. triphala has been used in traditional medicine practice against certain diseases such as jaundice, fever, cough, eye diseases etc. in the present study phytochemical (phenolic, flavonoid and carotenoid) and antibacterial activities of aqueous and ethanol extracts of triphala and its individual components ( ... | 2007 | 17273983 |
| new animal model of shigellosis in the guinea pig: its usefulness for protective efficacy studies. | it has been difficult to evaluate the protective efficacy of vaccine candidates against shigellosis, a major form of bacillary dysentery caused by shigella spp. infection, because of the lack of suitable animal models. to develop a proper animal model representing human bacillary dysentery, guinea pigs were challenged with virulent shigella flexneri serotype 2a (strains 2457t or ysh6000) or s. flexneri 5a (strain m90t) by the intrarectal (i.r.) route. interestingly, all guinea pigs administered ... | 2007 | 17277155 |
| bioluminescent signal system: bioluminescence immunoassay of pathogenic organisms. | the ca(2+)-regulated photoprotein obelin has been examined as a label for bioluminescence immunoassay of infective agents. the hepatitis b virus (hbsag) and the bacteria escherichia coli and shigella sonnei lipopolysaccharide (lps) were chosen as model antigens. chemically synthesized obelin-corresponding antibody conjugates were used in a solid-phase microplate immunoassay. the sensitivities achieved by the assay were 0.25 ng/ml for s. sonnei lps and 0.375 ng/ml for hbsag. a novel, filter-based ... | 2007 | 17286244 |
| gene expression profiling of the ph response in shigella flexneri 2a. | the ph response of shigella flexneri 2a 301 was identified by gene expression profiling. gene expression profiles of cells grown in ph 4.5 or 8.6 were compared with the profiles of cells grown at ph 7.0. differential expression was observed for 307 genes: 97 were acid up-regulated, 102 were acid down-regulated, 91 were base up-regulated, and 86 were base down-regulated. twenty-seven genes were found to be both acid and base up-regulated, and 29 genes were both acid and base down-regulated. this ... | 2007 | 17286558 |
| o-specific [corrected] polysaccharide conjugate vaccine-induced [corrected] antibodies prevent invasion of shigella into caco-2 cells and may be curative. | the o-specific polysaccharide (o-sp) domain of shigella lps is both an essential virulence factor and a protective antigen for this genus. a critical level of serum igg anti-o-sp was shown to confer immunity to shigellosis, likely by complement-mediated bacteriolysis of the inoculum. conjugate shigella o-sp vaccines were shown to be safe and immunogenic in children, and, in a preliminary study, shigella sonnei vaccine was protective in young adults. characteristic of shigellosis is bacterial inv ... | 2007 | 17287349 |
| capping of actin filaments by vinculin activated by the shigella ipaa carboxyl-terminal domain. | shigella, the causative agent of bacillary dysentery, invades epithelial cells. upon bacterial-cell contact, the type iii bacterial effector ipaa binds to the cytoskeletal protein vinculin to promote actin reorganization required for efficient bacterial uptake. we show that the last 74 c-terminal residues of ipaa (a559) bind to human vinculin (hv) and promotes its association with actin filaments. polymerisation experiments demonstrated that a559 was sufficient to induce hv-dependent partial cap ... | 2007 | 17289036 |
| seasonality in six enterically transmitted diseases and ambient temperature. | we propose an analytical and conceptual framework for a systematic and comprehensive assessment of disease seasonality to detect changes and to quantify and compare temporal patterns. to demonstrate the proposed technique, we examined seasonal patterns of six enterically transmitted reportable diseases (eds) in massachusetts collected over a 10-year period (1992-2001). we quantified the timing and intensity of seasonal peaks of ed incidence and examined the synchronization in timing of these pea ... | 2007 | 17291363 |
| study of polymorphic variable-number of tandem repeats loci in the ecor collection and in a set of pathogenic escherichia coli and shigella isolates for use in a genotyping assay. | the escherichia coli (e. coli) reference collection, ecor, consists of 72 strains that are representative of the genotypic diversity, as indexed by multilocus enzyme electrophoresis (mlee), in the species as a whole. mlee revealed 4 main phylogenetic groups designated a, b1, b2 and d. we present a study of the relationship between the ecor strains as determined by polymorphisms in seven variable-number of tandem repeats (vntr) loci. seven tandem repeats that were present in more than one of the ... | 2007 | 17291612 |
| shigella's ways of manipulating the host intestinal innate and adaptive immune system: a tool box for survival? | shigella, a gram-negative invasive enteropathogenic bacterium, causes the rupture, invasion and inflammatory destruction of the human colonic epithelium. this complex and aggressive process accounts for the symptoms of bacillary dysentery. the so-called invasive phenotype of shigella is linked to expression of a type iii secretory system (ttss) injecting effector proteins into the epithelial cell membrane and cytoplasm, thereby inducing local but massive changes in the cell cytoskeleton that lea ... | 2007 | 17213832 |
| case-control study of shigellosis in san francisco: the role of sexual transmission and hiv infection. | shigella species infect approximately 450,000 persons annually in the united states. person-to-person transmission of shigella species, which have a low infectious dose, occurs frequently, particularly in areas with poor sanitation and hygiene. sexual transmission of shigella species among men who have sex with men (msm) has been inferred from outbreaks of shigellosis among that population, and limited studies have suggested the importance of human immunodeficiency virus (hiv) infection as a ris ... | 2007 | 17205436 |
| another perfect storm: shigella, men who have sex with men, and hiv. | 2007 | 17205437 | |
| antimicrobial resistance patterns in enterobacteriaceae isolated from an urban wastewater treatment plant. | over 18 months, enterobacteria were isolated from the raw (189 isolates) and treated (156 isolates) wastewater of a municipal treatment plant. the isolates were identified as members of the genera escherichia (76%), shigella (7%), klebsiella (12%) and acinetobacter (4%). antimicrobial susceptibility phenotypes were determined using the agar diffusion method for the antibiotics amoxicillin, gentamicin, ciprofloxacin, sulfamethoxazole/trimethoprim, tetracycline and cephalothin, the disinfectants h ... | 2007 | 17250754 |
| shigella chromosomal ipah proteins are secreted via the type iii secretion system and act as effectors. | shigella possess 220 kb plasmid, and the major virulence determinants, called effectors, and the type iii secretion system (ttss) are exclusively encoded by the plasmid. the genome sequences of s. flexneri strains indicate that several ipah family genes are located on both the plasmid and the chromosome, but whether their chromosomal ipah cognates can be secreted from shigella remains unknown. here we report that s. flexneri strain, ysh6000 encodes seven ipah cognate genes on the chromosome and ... | 2007 | 17214743 |
| tumor-specific colonization, tissue distribution, and gene induction by probiotic escherichia coli nissle 1917 in live mice. | systemic administration of microorganisms into tumor-bearing mice revealed preferential accumulation in tumors in comparison to clearance in organs such as spleen and liver. here we compared the efficiency of tumor-specific colonization of pathogenic salmonella typhimurium strains 14028 and sl1344 to the enteroinvasive escherichia coli 4608-58 strain and to the attenuated salmonella flexneri 2a sc602 strain, as well as to the uropathogenic e. coli cft073, the non-pathogenic e. coli top10, and th ... | 2007 | 17448724 |
| dna microarray-based identification of serogroups and virulence gene patterns of escherichia coli isolates associated with porcine postweaning diarrhea and edema disease. | escherichia coli strains causing postweaning diarrhea (pwd) and edema disease (ed) in pigs are limited to a number of serogroups, with o8, o45, o138, o139, o141, o147, o149, and o157 being the most commonly reported worldwide. in this study, a dna microarray based on the o-antigen-specific genes of all 8 e. coli serogroups, as well as 11 genes encoding adhesion factors and exotoxins associated with pwd and ed, was developed for the identification of related serogroups and virulence gene patterns ... | 2007 | 17449692 |
| a deafness-associated mutant human connexin 26 improves the epithelial barrier in vitro. | a large proportion of recessive nonsyndromic hearing loss is due to mutations in the gjb2 gene encoding connexin 26 (cx26), a component of a gap junction. within different ethnic groups there are specific common recessive mutations, each with a relatively high carrier frequency, suggesting the possibility of heterozygous advantage. carriers of the r143w gjb2 allele, the most prevalent in the african population, present with a thicker epidermis than noncarriers. in this study, we show that (r143w ... | 2007 | 17581693 |
| genetic structure of the nada and nadb antivirulence loci in shigella spp. | comparison of nada and nadb in 14 shigella strains and enteroinvasive escherichia coli versus e. coli showed that at least one locus is altered in all strains. these observations explain the characteristic nicotinic acid auxotrophy of shigella organisms and are consistent with the previously identified antivirulence nature of these genes for these pathogens. | 2007 | 17586625 |
| [identification and characterization of diarrheal microorganisms]. | acute diarrhea belongs to group of diseases caused by pathogenic microorganisms - salmonella, shigella and pathogenic strains of e.coli. despite the prophylactic measurements morbidity rate of diarrheal diseases remains very high especially in children and in traveling persons. among the main causes of illness is emerging of new strains of microorganisms, new serological versions of already known pathogens or antibiotic resistant strains of these pathogens. struggle against the resistant forms o ... | 2007 | 17595460 |
| [study of antibiotic sensitivity of diarrheal microorganisms]. | as it was shown previously, detailed bacteriological analyses of 159 strains, among them museum and newly isolated strains of diarrheal patients from various clinics and bacteriology laboratories of tbilisi was carried out. study of antibiotic susceptibility of 52 strains of salmonella groups a, b, c, d, e and 42 shigella strains, among them 30 shigella flexneri and 12 shigella sonnei strains to 20 antibiotics and 1 chemical preparation was performed. 63% of salmonella strains were susceptible t ... | 2007 | 17595461 |
| analysis of the aerobactin and ferric hydroxamate uptake systems of yersinia pestis. | yersinia pestis genomes contain genes homologous to the aerobactin receptor (iuta) and biosynthetic genes (iucabcd) as well as the ferric hydroxamate uptake system (fhucdb) of escherichia coli. however, iuca is disrupted by a frameshift mutation. an e. coli strain carrying the cloned y. pestis aerobactin region was unable to produce aerobactin, but could use the siderophore as an iron source. repair of the frameshift mutation in iuca did not allow aerobactin production in e. coli or y. pestis. i ... | 2007 | 17600077 |
| nada and nadb of shigella flexneri 5a are antivirulence loci responsible for the synthesis of quinolinate, a small molecule inhibitor of shigella pathogenicity. | the evolution of bacterial pathogens from commensal organisms involves virulence gene acquisition followed by pathoadaptation to the new host, including inactivation of antivirulence loci (avl). avl are core ancestral genes whose expression is incompatible with the pathogenic lifestyle. previous studies identified cada (encoding lysine decarboxylase) as an avl of shigella spp. in this study, avl of shigella were identified by examining a phenotypic difference from its non-pathogenic ancestor, es ... | 2007 | 17600080 |
| introduction to united states department of agriculture vetnet: status of salmonella and campylobacter databases from 2004 through 2005. | in 2003 the united states department of agriculture established usda vetnet. it was modeled after pulsenet usa, the national molecular subtyping network for foodborne disease surveillance. the objectives of usda vetnet are: to use pulsed-field gel electrophoresis (pfge) to subtype zoonotic pathogens submitted to the animal arm of the national antimicrobial resistance monitoring system (narms); examine vetnet and pulsenet pfge patterns; and use the data for surveillance and investigation of suspe ... | 2007 | 17600492 |
| genetic relatedness among isolates of shigella sonnei carrying class 2 integrons in tehran, iran, 2002-2003. | shigella spp. are major cause of diarrhoeal disease in both developing and developed countries. shigella sonnei is the serogroup of shigella most frequently responsible for sporadic and epidemic enteritis in developed countries. in recent years the emergence and spread of s. sonnei biotype g carrying class 2 integron have been frequently reported in many countries. recently, s. sonnei has been reported as the prevalent serogroup of shigella in iran. the present study was carried out to investiga ... | 2007 | 17587439 |
| site-specific modification of shigella flexneri virf mrna by trna-guanine transglycosylase in vitro. | shigella flexneri is an enteropathogen responsible for severe dysentery in humans. virf is a key transcriptional regulator that activates the expression of the downstream virulence factors required for cellular invasion and cell-to-cell spread of this pathogen. there are several environmental factors that induce the translation of virf including temperature, ph, osmolarity and post-transcriptional rna modification. durand and colleagues (vacc, a virulence-associated chromosomal locus of shigella ... | 2007 | 17626052 |
| core-linked lps expression of shigella dysenteriae serotype 1 o-antigen in live salmonella typhi vaccine vector ty21a: preclinical evidence of immunogenicity and protection. | shigella dysenteriae serotype 1 (s. dysenteriae 1) causes severe shigellosis that is typically associated with high mortality. antibodies against shigella serotype-specific o-polysaccharide (o-ps) have been shown to be host protective. in this study, the rfb locus and the rfp gene with their cognate promoter regions were pcr-amplified from s. dysenteriae 1, cloned, and sequenced. deletion analysis showed that eight rfb orfs plus rfp are necessary for biosynthesis of this o-ps. a tandemly-linked ... | 2007 | 17629369 |
| [prevention and treatment of acute diarrhea in infants]. | the prognosis of acute diarrhoea in infants is most often satisfactory in industrialized countries. however, it has been estimated that 10 to 15 children die every year in france from acute dehydration due to acute diarrhoea. in spite of an increasing use over the least few years, oral rehydration solutions (ors) are used in only 70% of infants presenting with acute diarrhoea. the use of homemade ors, plain water or fizzy drink should be strictly avoided. in case of acute diarrhoea there is no i ... | 2007 | 17629685 |
| in vitro activity of cefadroxil, cephalexin, cefatrizine and cefpirome in presence of essential and trace elements. | evidences supporting the introduction of metallic elements in several biological processes are rapidly accumulating. likewise, many drugs possess modified toxicological and pharmacological properties when in the form of metal complexes. in order to ascertain the role of various essential and trace element complexation on the antibacterial activity of various cephalosporins, the synergistic or antagonistic behavior of cefadroxil, cephalexin, cefatrizine and cefpirome in presence of essential and ... | 2007 | 17604254 |
| rapid and simultaneous quantitation of escherichia coli 0157:h7, salmonella, and shigella in ground beef by multiplex real-time pcr and immunomagnetic separation. | the objective of this study was to establish a multiplex real-time pcr for the simultaneous quantitation of escherichia coli o157:h7, salmonella, and shigella. genomic dna for the real-time pcr was extracted by the boiling method. three sets of primers and corresponding taqman probes were designed to target these three pathogenic bacteria. multiplex real-time pcr was performed with taqman universal pcr master mix in an abi prism 7700 sequence detection system. final standard curves were calculat ... | 2007 | 17612065 |
| pathogenic bacteria associated with oysters (crassostrea brasiliana) and estuarine water along the south coast of brazil. | oysters and estuarine water samples were collected monthly, from june 1998 to march 1999, in the cananéia estuary, on the south coast of são paulo, brazil, and analyzed for bacterial hazards with and without depuration in filtered estuarine water. aeromonas spp., plesiomonas shigelloides, vibrio cholerae o1, vibrio parahaemolyticus, and vibrio vulnificus were counted in oyster samples using the most probable number (mpn) and their presence verified in the surrounding estuarine water samples. the ... | 2007 | 17613090 |
| prevalence of enterotoxigenic staphylococcus aureus and shigella spp. in some raw street vended indian foods. | in india, the street food trade is a growing sector with its expansion linked with urbanisation and the need of urban populations for both employment and food. however, the microbiological status of popularly consumed raw street foods, general hygienic and vending practices are not known. we visited 75 vendors (50 having fixed stalls and 25 with mobile stalls) operating in three major locations: mandi (open market place), bus terminus and railway station in new delhi and patiala city. a total of ... | 2007 | 17616871 |
| differences in the electrostatic surfaces of the type iii secretion needle proteins prgi, bsal, and mxih. | gram-negative bacteria use a needle-like protein assembly, the type iii secretion apparatus, to inject virulence factors into target cells to initiate human disease. the needle is formed by the polymerization of approximately 120 copies of a small acidic protein that is conserved among diverse pathogens. we previously reported the structure of the bsal needle monomer from burkholderia pseudomallei by nuclear magnetic resonance (nmr) spectroscopy and others have determined the crystal structure o ... | 2007 | 17617421 |
| distribution of serogroups and serotypes of multiple drug resistant shigella isolates. | summary | 2007 | 17622331 |
| [study on molecular epidemiology of shigella in hangzhou district during 1998 to 2005]. | 2007 | 17649701 | |
| the two-faced role of cad genes in the virulence of pathogenic escherichia coli. | in enterobacteria, acid stress induces expression of the cad system which is involved in maintaining intracellular ph at levels compatible with cell survival. despite its crucial role, the cad operon is silenced in shigella and in other pathogenic escherichia coli. in the present review, we will address the question of why and how the cad locus has been sacrificed for the sake of optimal expression of virulence traits. | 2007 | 17656072 |
| anaerobic regulation of shigella flexneri virulence: arca regulates fur and iron acquisition genes. | invasion and plaque formation in epithelial monolayers are routinely used to assess the virulence of shigella flexneri, a causative agent of dysentery. a modified plaque assay was developed to identify factors contributing to the virulence of s. flexneri under the anaerobic conditions present in the colon. this assay demonstrated the importance of the ferrous iron transport system feo, as well as the global transcription factors fur, arca, and fnr, for shigella plaque formation in anoxic environ ... | 2007 | 17660284 |
| identification of minor inner-membrane components of the shigella type iii secretion system 'needle complex'. | type iii secretion systems (t3sss or secretons) are central virulence factors of many gram-negative bacteria, used to inject protein effectors of virulence into eukaryotic host cells. their overall morphology, consisting of a cytoplasmic region, an inner- and outer-membrane section and an extracellular needle, is conserved in various species. a portion of the secreton, containing the transmembrane regions and needle, has been isolated biochemically and termed the 'needle complex' (nc). however, ... | 2007 | 17660405 |
| the acid-resistance pathways of shigella flexneri 2457t. | the stationary-phase acid-resistance pathways of shigella flexneri 2457t have not previously been studied. the two acid-resistance systems, the glutamate-dependent acid-resistance (gdar) and the oxidative pathways, reported elsewhere for escherichia coli and s. flexneri 3136, were both detected in s. flexneri 2457t. however, s. flexneri 2457t cells grown overnight under fermentative conditions and acid-shocked in minimal media in the absence of glutamate, an acid test often described as a negati ... | 2007 | 17660423 |
| shigella flexneri phagosomal escape is independent of invasion. | infections with salmonella enterica serovar typhimurium and shigella flexneri result in mucosal inflammation in response to epithelial cell invasion and macrophage cytotoxicity. these processes are mediated by type iii secretion systems encoded in homologous virulence loci in the two species, namely, salmonella pathogenicity island 1 (spi-1), carried in the genome, and the shigella entry region (ser), carried in a large virulence plasmid. here we show that spi-1 can functionally complement a del ... | 2007 | 17664266 |
| prevalence of bacterial pathogens in biofilms of drinking water distribution systems. | water for human consumption is required to be free from any bacteria that might pose a health risk. the presence of biofilms in the drinking water distribution system may play a role in the presence of potential pathogens in the drinking water supply. ninety-five biofilm samples from various parts of south africa were tested for the presence of escherichia coli, aeromonas, pseudomonas, salmonella, shigella and vibrio spp. members of these genera were quantified by the three-tube most probable nu ... | 2007 | 17674571 |
| genes under positive selection in escherichia coli. | we used a comparative genomics approach to identify genes that are under positive selection in six strains of escherichia coli and shigella flexneri, including five strains that are human pathogens. we find that positive selection targets a wide range of different functions in the e. coli genome, including cell surface proteins such as beta barrel porins, presumably because of the involvement of these genes in evolutionary arms races with other bacteria, phages, and/or the host immune system. st ... | 2007 | 17675366 |
| recent gene conversions between duplicated glutamate decarboxylase genes (gada and gadb) in pathogenic escherichia coli. | escherichia coli have evolved adaptive systems to resist strongly acidic habitats in part through the production of 2 biochemically identical isoforms of glutamate decarboxylase (gad), encoded by the gada and gadb genes. these genes occur in e. coli and other members of the genospecies (e.g., shigella spp.) and originated as part of a genomic fitness island acquired early in escherichia evolution. the present duplicated gad loci are widely spaced on the e. coli chromosome, and the 2 genes are 97 ... | 2007 | 17675652 |
| serum sperm antibodies after diarrhoeal diseases. | the origin of 'natural' anti-sperm antibodies found in fertile humans, virgin girls, and boys before puberty, is quite obscure. one hypothetical mechanism relates their existence to inflammatory gastrointestinal entities: as a result of the disease, cross-reactive antibodies produced against gastrointestinal flora bind spermatozoa. to test this assumption, we evaluated the level of serum sperm antibodies after diarrhoeal infections. serum samples from 17 patients with shigellosis and 12 patients ... | 2007 | 17683470 |
| escherichia coli, shigella and salmonella species in acute diarrhoea in hamedan, islamic republic of iran. | this study investigated the frequency of escherichia col, shigella and salmonella species in stool specimens from patients with diarrhoea presenting to health centres in hamedan province, islamic republic of iran. from 144 samples, shigella strains were isolated in 17 cases (11.8%): 10 sh. flexneri, 3 sh. sonnei, 2 sh. boydii and 2 untyped strains. no salmonella strains were isolated. using molecular diagnostic methods, diarrheogenic e. coli were detected in 37 cases (25.7%), the majority were e ... | 2007 | 17684844 |
| outbreaks where food workers have been implicated in the spread of foodborne disease. part 1. description of the problem, methods, and agents involved. | food workers in many settings have been responsible for foodborne disease outbreaks for decades, and there is no indication that this is diminishing. the committee on control of foodborne illnesses of the international association for food protection was tasked with collecting and evaluating any data on worker-associated outbreaks. a total of 816 reports with 80,682 cases were collected from events that occurred from 1927 until the first quarter of 2006. most of the outbreaks reviewed were from ... | 2007 | 17685355 |
| postinfectious irritable bowel syndrome: a long-term consequence of bacterial gastroenteritis. | irritable bowel syndrome (ibs) is a commonly diagnosed disease characterized by gastrointestinal symptoms that may be associated with psychological illness and emotional problems. the prevalence rate worldwide for ibs ranges from 10 to 20% and is higher for women than for men. ibs imposes a substantial financial burden on both patients and employers because of increased medical costs and decreased work productivity. recent studies indicate that inflammatory processes involving the gastrointestin ... | 2007 | 17685356 |
| reduced selection leads to accelerated gene loss in shigella. | obligate pathogenic bacteria lose more genes relative to facultative pathogens, which, in turn, lose more genes than free-living bacteria. it was suggested that the increased gene loss in obligate pathogens may be due to a reduction in the effectiveness of purifying selection. less attention has been given to the causes of increased gene loss in facultative pathogens. | 2007 | 17686180 |
| [pathogens trapped in neutrophils nets]. | 2007 | 17502056 | |
| relationships between bacteroides 16s rrna genetic markers and presence of bacterial enteric pathogens and conventional fecal indicators. | occurrence and prevalence of different bacterial enteric pathogens as well as their relationships with conventional (total and fecal coliforms) and alternative fecal indicators (host-specific bacteroides 16s rrna genetic markers) were investigated for various water samples taken from different sites with different degrees of fecal contamination. the results showed that a wide range of bacterial pathogens could be detected in both municipal wastewater treatment plant samples and in surface water ... | 2007 | 17507075 |
| immunogenicity and protective efficacy offered by a ribosomal-based vaccine from shigella flexneri 2a. | shigellosis is a major form of bacillary dysentery caused by shigella infection. shigella ribosome-based vaccines (srv), considered among the potent vaccine candidates, are composed of o-antigen and ribosome isolated from s. flexneri 2a. to investigate the immunogenicity and protective efficacy of srv, mice were vaccinated with srv via the intranasal (i.n.) route. interestingly, robust levels of shigella-derived lps-specific igg and iga abs and antibody-forming cells were elicited in systemic an ... | 2007 | 17507120 |
| epidemiology and evolution of genotype and antimicrobial resistance of an imported shigella sonnei clone circulating in central taiwan. | shigella sonnei replaced shigella flexneri to become the predominant species for shigellosis in 2001 to 2003 in central taiwan. a total of 425 s. sonnei isolates collected from 1996 to 2004 were available for characterization by pulsed-field gel electrophoresis (pfge), inter-is1 spacer typing (ist), and antimicrobial susceptibility testing. the results showed that at least 21 ist clones had emerged for the s. sonnei infections in 1996 to 2004. most ist clones lasted for a short time; some circul ... | 2007 | 17509797 |