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pathogen specific carbohydrate antigen microarrays: a chip for detection of salmonella o-antigen specific antibodies.a salmonella o-antigen microarray was developed by covalent coupling of oligosaccharide antigens specific for serogroups salmonella enterica sv. paratyphi (group a), typhimurium (group b) and enteritidis (group d). antibodies were correctly detected in sera from patients with culture verified salmonellosis. high serogroup-specificity was seen with the disaccharide antigens. with the larger antigens, containing the backbone sequence manalpha1-2rhaalpha1-2gal (mrg), common backbone-specific antibo ...200817558551
experimental reproduction of bovine salmonella encephalopathy using a norepinephrine-based stress model.neurological disease represents a sporadic but serious manifestation of bovine salmonellosis that is thought to be related to systemic infection. salmonella enterica serovar dublin (s. dublin) is the serovar most associated with systemic infection in cattle, although reports of neurological disease associated with s. dublin or any other serovar are rare and usually anecdotal. this study reports the involvement of three strains of s. enterica, serovars saintpaul, montevideo, and enteritidis, in s ...200817324598
molecular typing of salmonella enterica serovars enteritidis, corvallis, anatum and typhimurium from food and human stool samples in tunisia, 2001-2004.during the period from 2001 to 2004, a total of 72 isolates of salmonella enterica serovars: anatum (n=40), enteritidis (n=18), corvallis (n=8), and typhimurium (n=6), of various origins (mainly food and diarrhoeagenic stool samples), were collected and further characterized by antibiotic resistance, plasmid analysis, and pulsed-field gel electrophoresis (pfge). forty-five isolates presented multidrug resistance to antibiotics. among which one s. enterica serovar anatum isolate was resistant to ...200817568477
the distribution of acetohydroxyacid synthase in soil bacteria.most bacteria possess the enzyme acetohydroxyacid synthase, which is used to produce branched-chain amino acids. enteric bacteria contain several isozymes suited to different conditions, but the distribution of acetohydroxyacid synthase in soil bacteria is largely unknown. growth experiments confirmed that escherichia coli, salmonella enterica serotype typhimurium, and enterobacter aerogenes contain isozymes of acetohydroxyacid synthase, allowing the bacteria to grow in the presence of valine (w ...200817624809
cytokine gene expression in chicken cecal tonsils following treatment with probiotics and salmonella infection.probiotics are currently employed for control of pathogens and enhancement of immune response in chickens. in this study, we investigated the underlying immunological mechanisms of the action of probiotics against colonization of the chicken intestine by salmonella enterica subsp. enterica serovar typhimurium (salmonella serovar typhimurium). birds received probiotics by oral gavage on day 1 of age and, subsequently, received salmonella serovar typhimurium on day 2 of age. cecal tonsils were rem ...200817681719
improving live attenuated bacterial carriers for vaccination and therapy.live attenuated bacteria are well established as vaccines. thus, their use as carriers for prophylactic and therapeutic macromolecules is a logical consequence. here we describe several experimental applications of bacteria to carry heterologous macromolecules into the murine host. first, listeria monocytogenes are described that are able to transfer eukaryotic expression plasmids into host cells for gene therapy. high multiplicities of infection are still required for efficient gene transfer an ...200817702649
salmonella enterica serotype typhimurium carrying hybrid virulence-resistance plasmids (puo-stvr): a new multidrug-resistant group endemic in spain.the epidemiological impact in spain of an emerging group of multidrug-resistant salmonella enterica serotype typhimurium, characterized by the presence of virulence-resistance hybrid plasmids (termed puo-stvr) that are related to the s. typhimurium virulence plasmid pslt, was evaluated. adscription to the group was based on detection of the bla(oxa-1) gene (encoding ampicillin resistance) by pcr, and identification of a puo-stvr plasmid through hybridization with specific probes for virulence (s ...200817597002
stec is a salmonella kinase required for spi-2-dependent f-actin remodelling.salmonella enterica serovar typhimurium (s. typhimurium) replicates inside mammalian cells within membrane-bound compartments called salmonella-containing vacuoles. intracellular replication is dependent on the activities of several effector proteins translocated across the vacuolar membrane by the salmonella pathogenicity island 2 (spi-2)-type iii secretion system (t3ss). this is accompanied by the formation in the vicinity of bacterial vacuoles of an f-actin meshwork, thought to be involved in ...200817645553
clonal diversity of salmonella enterica serotype typhi isolated from patients with typhoid fever in tehran.in this study, antimicrobial susceptibility test and genetic typing were used to characterize 15 salmonella enterica serotype typhi (s. typhi) isolates recovered from sporadic cases of typhoid fever in tehran, iran during 2004. antimicrobial susceptibility test showed that all isolates were susceptible to 20 antimicrobials examined in this study. analysis of insertion elements showed that 2 is200 types with 10 and 11 copies were present. 11 of the 15 isolates were found to possess 10 is200 eleme ...200817852914
structural characterization and serological specificities of lipopolysaccharides from salmonella enterica serovar gallinarum biovar pullorum standard, intermediate and variant antigenic type strains.the structure and serological specificities of the lipopolysaccharides (lpss) from salmonella enterica serovar gallinarum biovar pullorum were studied to provide an improved basis for the distinction between antigenic types and the development of improved diagnostic tests. the structure of the lps o-polysaccharide (o-ps) from s. pullorum standard, intermediate and variant antigenic type strains was determined by mass spectrometry, nuclear magnetic resonance spectroscopy and chemical analysis. th ...200817855026
bringing order to a complex molecular machine: the assembly of the bacterial flagella.the bacterial flagellum is an example of elegance in molecular engineering. flagella dependent motility is a widespread and evolutionarily ancient trait. diverse bacterial species have evolved unique structural adaptations enabling them to migrate in their environmental niche. variability exists in the number, location and configuration of flagella, and reflects unique adaptations of the microorganism. the most detailed analysis of flagellar morphogenesis and structure has focused on escherichia ...200817719558
osteoblasts express nlrp3, a nucleotide-binding domain and leucine-rich repeat region containing receptor implicated in bacterially induced cell death.bacterially induced osteoblast apoptosis may be a major contributor to bone loss during osteomyelitis. we provide evidence for the functional expression in osteoblasts of nlrp3, a member of the nlr family of cytosolic receptors that has been implicated in the initiation of programmed cell death.200817907925
the salmonella enterica serotype typhi regulator tvia reduces interleukin-8 production in intestinal epithelial cells by repressing flagellin secretion.unlike non-typhoidal salmonella serotypes, s. enterica serotype typhi does not elicit neutrophilic infiltrates in the human intestinal mucosa. the vi capsule-encoding tviabcdevexabcde operon (viab locus) is a s. typhi-specific dna region preventing production of interleukin (il)-8 during infection of intestinal epithelial cells. we elucidated the mechanism by which the viab locus reduces il-8 production in human colonic epithelial (t84) cells. a s. typhi tviabcdevexabcde deletion mutant, but not ...200817725646
part i. analysis of data gaps pertaining to salmonella enterica serotype typhi infections in low and medium human development index countries, 1984-2005.there are only 10 contemporary, population-based studies of typhoid fever that evaluate disease incidence using blood culture for confirmation of cases. reported incidence ranged from 13 to 976/100 000 persons per year. these studies are likely to have been done preferentially in high- incidence sites which makes generalization of data difficult. only five of these studies reported mortality. of these the median (range) mortality was 0% (0-1.8%). since study conditions usually involved enhanced ...200817686194
gastrointestinal microbial ecology and the safety of our food supply as related to salmonella.salmonella causes an estimated 1.3 million human foodborne illnesses and more than 500 deaths each year in the united states, representing an annual estimated cost to the economy of approximately $2.4 billion. salmonella enterica comprises more than 2,500 serotypes. with this genetic and environmental diversity, serotypes are adapted to live in a variety of hosts, which may or may not manifest with clinical illness. thus, salmonella presents a multifaceted threat to food production and safety. s ...200817878279
structural biology of membrane-intrinsic beta-barrel enzymes: sentinels of the bacterial outer membrane.the outer membranes of gram-negative bacteria are replete with integral membrane proteins that exhibit antiparallel beta-barrel structures, but very few of these proteins function as enzymes. in escherichia coli, only three beta-barrel enzymes are known to exist in the outer membrane; these are the phospholipase ompla, the protease ompt, and the phospholipidcolon, two colonslipid a palmitoyltransferase pagp, all of which have been characterized at the structural level. structural details have al ...200817880914
multidrug resistance of salmonella enterica serovars typhi and typhimurium isolated from clinical samples at two rural hospitals in western kenya.the threat to human health posed by antibiotic resistance is of growing concern. many commensals and pathogenic organisms have developed resistance to well established and newer antibiotics. this is a cross-sectional study within two hospital settings to determine in vitro antibiotic susceptibilities of salmonella species isolated in blood, cerebral spinal fluid, pus and stool collected from in- and out-patients. the inclusion criteria was non restrictive to in- and out-patient but preference to ...200819738333
comparative study of leaf and stem bark extracts of parkia biglobosa against enterobacteria.hydroethanolic and aqueous extracts of leaf and stem bark of parkia biglobosa (jacq) benth. (mimosaceae) were tested against clinical isolates escherichia coli, salmonella typhi, shigella dysenteriae and enterococcus faecalis, and corresponding collection strains e. coli cip 105 182, salmonella enterica cip 105 150, shigella dysenteriae cip 54-51 and enterococcus faecalis cip 103 907. discs of gentamicin, a broad spectrum antibiotic were used as positive controls. the results showed that all the ...200820161943
investigation of an outbreak of salmonella enterica subsp. enterica serovar hadar food illness in the abruzzi region of italy.a comparative study was made of 22 strains of salmonella hadar isolated from victims of an outbreak of food illness in the abruzzi region of italy in 2000 and 21 strains of the same serotype isolated from poultry meat and human stool samples in the abruzzi and molise regions between 2000 and 2001. the aim of the investigation was to provide an epidemiological interpretation of the food illness outbreak to establish the degree of similarity between the s. hadar strains isolated from victims of th ...200820405442
development of an oligonucleotide microarray method for salmonella serotyping.adequate identification of salmonella enterica serovars is a prerequisite for any epidemiological investigation. this is traditionally obtained via a combination of biochemical and serological typing. however, primary strain isolation and traditional serotyping is time-consuming and faster methods would be desirable. a microarray, based on two housekeeping and two virulence marker genes (atpd, gyrb, flic and fljb), has been developed for the detection and identification of the two species of sal ...200821261872
control of salmonella enterica serovar enteritidis in laying hens by inactivated salmonella enteritidis vaccines.salmonella enteritidis is one of the agents that is responsible for outbreaks of human foodborne salmonellosis caused by salmonella enteritidis and is generally associated with the consumption of poultry products. inactivated salmonella enteritidis cell vaccine is one of the available methods to control salmonella enteritidis in breeders and laying hens, however results in terms of efficacy vary. this vaccine has never been tested in brazil, therefore, the present work was carried out to assess ...200824031235
cytotoxic t cell adjuvant effects of three salmonella enterica flagellins.bacterial flagellins are important virulence-associated factors and strong inducers of inflammatory responses in mammalian hosts. flagellins have also been investigated as potential vaccine adjuvants, either for induction of humoral or cellular immune responses, to different target antigens. in this study we investigated the adjuvant properties of three salmonella enterica flagellins types (flicd, flici and fljb) to an ovalbumin-derived cd8(+) t cell-restricted epitope (ova257-264). although mic ...200824031176
the aerobic and anaerobic respiratory chain of escherichia coli and salmonella enterica: enzymes and energetics.escherichia coli contains a versatile respiratory chain which oxidizes ten different electron donor substrates and transfers the electrons to terminal reductases or oxidases for the reduction of six different electron acceptors. salmonella is able to use even two more electron acceptors. the variation is further increased by the presence of isoenzymes for some substrates. various respiratory pathways can be established by combining the oxidation of different electron donors and acceptors which a ...200826443736
biosynthesis and use of cobalamin (b12).this review summarizes research performed over the last 23 years on the genetics, enzyme structures and functions, and regulation of the expression of the genes encoding functions involved in adenosylcobalamin (adocbl, or coenzyme b12) biosynthesis. it also discusses the role of coenzyme b12 in the physiology of salmonella enterica serovar typhimurium lt2 and escherichia coli. john roth's seminal contributions to the field of coenzyme b12 biosynthesis research brought the power of classical and ...200826443728
magnesium transport and magnesium homeostasis.this review reviews the properties and regulation of the salmonella enterica serovar typhimurium and escherichia coli transporters that mediate mg2+ influx: cora and the mgt p-type atpases. in addition, potential mg2+ regulation of transcription and translation, largely via the phopq two component system, is discussed. cora proteins are a unique class of transporters and are widespread in the bacteria and archaea, with rather distant but functional homologs in eukaryotes. the mgt transporters ar ...200826443723
salmonella enterica serotype 4,5,12:i:-, an emerging salmonella serotype that represents multiple distinct clones.the prevalence, among human clinical cases, of salmonella enterica serotype 4,5,12:i:-, a serotype antigenically similar to salmonella enterica serotype typhimurium but lacking second-phase flagellar antigens, has increased considerably over the last 10 years. to probe the evolution and ecology of this emerging serotype, we characterized 190 salmonella isolates initially classified as salmonella serotypes 4,5,12:i:- (n = 90) and typhimurium (n = 100) and obtained from various sources in the unit ...200919741087
salmonella enterica serovar typhi-specific immunoglobulin a antibody responses in plasma and antibody in lymphocyte supernatant specimens in bangladeshi patients with suspected typhoid fever.many currently available diagnostic tests for typhoid fever lack sensitivity and/or specificity, especially in areas of the world where the disease is endemic. in order to identify a diagnostic test that better correlates with typhoid fever, we evaluated immune responses to salmonella enterica serovar typhi (serovar typhi) in individuals with suspected typhoid fever in dhaka, bangladesh. we enrolled 112 individuals with suspected typhoid fever, cultured day 0 blood for serovar typhi organisms, a ...200919741090
characteristics and dynamics of salmonella contamination along the coast of agadir, morocco.the occurrence of salmonella enterica in the environment of tropical and desert regions has remained largely uninvestigated in many areas of the world, including africa. in the present study, we investigated the presence of salmonella spp. along 122 km of the coastline of agadir (southern morocco) in relation to environmental parameters. a total of 801 samples of seawater (243), marine sediment (279), and mussels (279) were collected from six sites between july 2004 and may 2008. the overall pre ...200919820155
the tbk1 adaptor and autophagy receptor ndp52 restricts the proliferation of ubiquitin-coated bacteria.cell-autonomous innate immune responses against bacteria attempting to colonize the cytosol of mammalian cells are incompletely understood. polyubiquitylated proteins can accumulate on the surface of such bacteria, and bacterial growth is restricted by tank-binding kinase (tbk1). here we show that ndp52, not previously known to contribute to innate immunity, recognizes ubiquitin-coated salmonella enterica in human cells and, by binding the adaptor proteins nap1 and sintbad, recruits tbk1. knockd ...200919820708
evidence for il-6 promoter nuclear activation in u937 cells stimulated with salmonella enterica serovar typhimurium porins.interleukin-6 (il-6) is a pleiotropic cytokine and plays an active role in inflammatory and immune responses, contributing to a multitude of physiological and pathophysiological processes. in this study, we address the molecular mechanism of il-6 transcriptional induction and propose a correlation between activated nf-kappab localization and il-6 expression. in particular, we detected, by chip assay, that occupation of the il-6 gene promoter site is dependent on activated nf-kappab. in fact, aft ...200919825524
simultaneous assay of every salmonella typhi gene using one million transposon mutants.very high-throughput sequencing technologies need to be matched by high-throughput functional studies if we are to make full use of the current explosion in genome sequences. we have generated a very large bacterial mutant pool, consisting of an estimated 1.1 million transposon mutants and we have used genomic dna from this mutant pool, and illumina nucleotide sequencing to prime from the transposon and sequence into the adjacent target dna. with this method, which we have called tradis (transpo ...200919826075
a novel inhibitor of chlamydophila pneumoniae protein kinase d (pknd) inhibits phosphorylation of cdsd and suppresses bacterial replication.we have shown previously that chlamydophila pneumoniae contains a dual-specific ser/thr protein kinase that phosphorylates cdsd, a structural component of the type iii secretion apparatus. to further study the role of pknd in growth and development we sought to identify a pknd inhibitor to determine whether pknd activity is required for replication.200919828035
the plague of athens: epidemiology and paleopathology.in 430 bc, a plague struck the city of athens, which was then under siege by sparta during the peloponnesian war (431-404 bc). in the next 3 years, most of the population was infected, and perhaps as many as 75,000 to 100,000 people, 25% of the city's population, died. the athenian general and historian thucydides left an eye-witness account of this plague and a detailed description to allow future generations to identify the disease should it break out again. because of the importance of thucyd ...200919787658
salmonella enterica serovar typhi with ctx-m beta-lactamase, germany. 200919788837
diagnosis of endotoxemia with gram-negative bacteremia is bacterial species dependent: a meta-analysis of clinical studies.endotoxemia is undetectable for up to 60% of cases of bacteremia caused by gram-negative (gn) species, a discordance attributed to the limitations of the limulus assay for endotoxemia. the lipid a structure of the endotoxin molecule is critical for the sensing of gn bacteria by the host immune system although not so for sensing by the limulus assay. the lipid a structure of commensal enterobacteriaceae is hexa-acyl, whereas non-enterobacteriaceae have a broader range of structures. by using a pr ...200919794055
bacterial growth rate and host factors as determinants of intracellular bacterial distributions in systemic salmonella enterica infections.bacteria of the species salmonella enterica cause a range of life-threatening diseases in humans and animals worldwide. the within-host quantitative, spatial, and temporal dynamics of s. enterica interactions are key to understanding how immunity acts on these infections and how bacteria evade immune surveillance. in this study, we test hypotheses generated from mathematical models of in vivo dynamics of salmonella infections with experimental observation of bacteria at the single-cell level in ...200919797065
effect of the o-antigen length of lipopolysaccharide on the functions of type iii secretion systems in salmonella enterica.the virulence of salmonella enterica critically depends on the functions of two type iii secretion systems (t3ss), with the salmonella pathogenicity island 1 (spi1)-encoded t3ss required for host cell invasion and the spi2-t3ss enabling salmonella to proliferate within host cells. a further t3ss is required for the assembly of the flagella. most serovars of salmonella also possess a lipopolysaccharide with a complex o-antigen (oag) structure. the number of oag units attached to the core polysacc ...200919797066
superior protective immunity against murine listeriosis by combined vaccination with cpg dna and recombinant salmonella enterica serovar typhimurium.preexisting antivector immunity can severely compromise the ability of salmonella enterica serovar typhimurium live vaccines to induce protective cd8 t-cell frequencies after type iii secretion system-mediated heterologous protein translocation in orally immunized mice. to circumvent this problem, we injected cpg dna admixed to the immunodominant p60(217-225) peptide from listeria monocytogenes subcutaneously into balb/c mice and coadministered a p60-translocating salmonella strain by the orogas ...200919797070
dsbl and dsbi contribute to periplasmic disulfide bond formation in salmonella enterica serovar typhimurium.disulfide bond formation in periplasmic proteins is catalysed by the dsba/dsbb system in most gram-negative bacteria. salmonella enterica serovar typhimurium also encodes a paralogous pair of proteins to dsba and dsbb, dsbl and dsbi, respectively, downstream of a periplasmic arylsulfate sulfotransferase (asst). we show that dsbl and dsbi function as a redox pair contributing to periplasmic disulfide bond formation and, as such, affect transcription of the salmonella pathogenicity island 1 (spi1) ...200919797361
edible apple film wraps containing plant antimicrobials inactivate foodborne pathogens on meat and poultry products.apple-based edible films containing plant antimicrobials were evaluated for their activity against pathogenic bacteria on meat and poultry products. salmonella enterica or e. coli o157:h7 (10(7) cfu/g) cultures were surface inoculated on chicken breasts and listeria monocytogenes (10(6) cfu/g) on ham. the inoculated products were then wrapped with edible films containing 3 concentrations (0.5%, 1.5%, and 3%) of cinnamaldehyde or carvacrol. following incubation at either 23 or 4 degrees c for 72 ...200919799671
activated by different signals, the phop/phoq two-component system differentially regulates metal uptake.the phop/phoq two-component system controls several physiological and virulence functions in salmonella enterica. this system is activated by low mg(2+), acidic ph, and antimicrobial peptides, but the biological consequences resulting from sensing multiple signals are presently unclear. here, we report that the phop/phoq system regulates different salmonella genes depending on whether the inducing signal is acidic ph or low mg(2+). when salmonella experiences acidic ph, the phop/phoq system prom ...200919801407
analysis of the variability in the number of viable bacteria after mild heat treatment of food.variability in the numbers of bacteria remaining in saline solution and whole milk following mild heat treatment has been studied with listeria innocua, enterococcus faecalis, salmonella enterica serovar enteritidis, and pseudomonas fluorescens. as expected, the most heat-resistant bacterium was e. faecalis, while p. fluorescens was the least heat resistant, and all bacteria showed greater thermal resistance in whole milk than in saline solution. despite the differences in the inactivation kinet ...200919801476
neonatal sepsis due to salmonella typhi and paratyphi a.sepsis due to salmonella enterica serovar typhi and paratyphi a is rare in neonates. though described as a mild and unrecognized illness in infants, life-threatening complications and even deaths have been reported. we present five cases of neonatal septicaemia due to s. typhi and s. paratyphi a. the cases were presented because of their interesting clinical presentations and possible modes of transmission. salmonella infections should be considered in the differential diagnosis of sepsis neonat ...200919801808
autophagy in immunity against intracellular bacteria.autophagy is an innate immune defense mechanism against various intracellular bacterial pathogens, such as salmonella enterica serovar typhimurium (s. typhimurium), listeria monocytogenes and shigella flexneri. s. typhimurium uses type three secretion systems (t3sss) to invade mammalian cells and replicate in salmonella-containing vacuoles (scvs). a small population of intracellular s. typhimurium is targeted by autophagy shortly after infection. evidence suggests that these bacteria are present ...200919802566
a coiled-coil motif that sequesters ions to the hydrophobic core.most core residues of coiled coils are hydrophobic. occasional polar residues are thought to lower stability, but impart structural specificity. the coiled coils of trimeric autotransporter adhesins (taas) are conspicuous for their large number of polar residues in position d of the core, which often leads to their prediction as natively unstructured regions. the most frequent residue, asparagine (n@d), can occur in runs of up to 19 consecutive heptads, frequently in the motif [i/v]xxntxx. in th ...200919805097
increased expression of mg(2+) transport proteins enhances the survival of salmonella enterica at high temperature.mg(2+) homeostasis is important for salmonella pathogenesis. in salmonella enterica, the transcription of the mgta gene, which encodes a mg(2+) transporter, is regulated by a mg(2+)-sensing riboswitch [cromie mj, shi y, latifi t, groisman ea (2006) cell 125:71-84]. in a genetic analysis of the determinants of thermotolerance in s. enterica serovar typhimurium, we isolated the chr-1 mutation that increased the resistance of exponential phase cells to killing by high temperature. this mutation is ...200919805196
the long-lived nature of clostridium perfringens iota toxin in mammalian cells induces delayed apoptosis.mono-adp ribosylation of actin by bacterial toxins, such as clostridium perfringens iota or clostridium botulinum c2 toxins, results in rapid depolymerization of actin filaments and cell rounding. here we report that treatment of african green monkey kidney (vero) cells with iota toxin resulted in delayed caspase-dependent death. unmodified actin did not reappear in toxin-treated cells, and enzyme-active toxin was detectable in the cytosol for at least 24 h. c2 toxin showed comparable, long-live ...200919805536
regulated delayed expression of rfah in an attenuated salmonella enterica serovar typhimurium vaccine enhances immunogenicity of outer membrane proteins and a heterologous antigen.rfah is a transcriptional antiterminator that reduces the polarity of long operons encoding secreted and surface-associated cell components of salmonella enterica serovar typhimurium, including o antigen and lipopolysaccharide core sugars. a deltarfah mutant strain is attenuated in mice (50% lethal dose [ld(50)], >10(8) cfu). to examine the potential for using rfah in conjunction with other attenuating mutations, we designed a series of strains in which we replaced the native rfah promoter with ...200919805538
eradication of intracellular salmonella enterica serovar typhimurium with a small-molecule, host cell-directed agent.eradication of intracellular pathogenic bacteria with host-directed chemical agents has been an anticipated innovation in the treatment of antibiotic-resistant bacteria. we previously synthesized and characterized a novel small-molecule agent, ar-12, that induces autophagy and inhibits the akt kinase in cancer cells. as both autophagy and the akt kinase have been shown recently to play roles in the intracellular survival of several intracellular bacteria, including salmonella enterica serovar ty ...200919805568
changing trends in antimicrobial resistance of salmonella enterica serovar typhi and salmonella enterica serovar paratyphi a in chennai.chloramphenicol was considered the anti-microbial gold standard for typhoid treatment but, following the increasing worldwide frequency of antibiotic resistance, ciprofloxacin has been the mainstay of therapy since 1980. recent studies have shown a shifting of susceptibility to conventional drugs like chloramphenicol, ampicillin and cotrimoxazole. the primary objective of the study was to evaluate the in vitro activity of chloramphenicol and other first-line drugs in comparison with cephalospori ...200919805957
m-01zh09, an oral live attenuated salmonella enterica serovar typhi vaccine for the prevention of typhoid fever.typhoid fever remains a major health problem globally, particularly in the developing world. the increased emergence of several multidrug-resistant strains of salmonella enterica serovar typhi has made the management of the disease increasingly difficult. although vaccines against typhoid fever are available, improvements are desired in dosage, immunogenicity and tolerability. emergent biosolutions inc is developing m-01zh09, a single-dose oral vaccine against typhoid fever based on an attenuate ...200919806505
identification of salmonella pullorum genomic sequences using suppression subtractive hybridization.pullorum disease affecting poultry is caused by salmonella enterica serovar pullorum and results in severe economic loss every year, especially in countries with a developing poultry industry. the pathogenesis of s. pullorum is not yet well defined, as the specific virulence factors still need to be identified. thus, to isolate specific dna fragments belonging to s. pullorum, this study used suppression subtractive hybridization. as such, the genome of the s. pullorum c79-13 strain was subtracte ...200919809245
overexpression, purification, and immunogenicity of recombinant porin proteins of salmonella enterica serovar typhi (s. typhi).porin proteins of gram-negative bacteria are outer membrane proteins that act as receptors for bacteriophages and are involved in a variety of functions like solute transport, pathogenesis, and immunity. salmonella enterica serovar typhi (s. typhi), a gram-negative bacterium, is the causative agent of typhoid fever. porins of s. typhi have been shown to have a potential role in diagnostics and vaccination. in the present study, the major outer membrane proteins ompf and ompc from s. typhi were c ...200919809263
a tdca mutation reduces the invasive ability of salmonella enterica serovar typhimurium.we previously observed that the transcription of some flagellar genes decreased in salmonella typhimurium tdca mutant, which is a gene encoding the transcriptional activator of the tdc operon. since flagella-mediated bacterial motility accelerates the invasion of salmonella, we have examined the effect of tdca mutation on the invasive ability as well as the flagellar biosynthesis in s. typhimurium. a tdca mutation caused defects in motility and formation of flagellin protein, flic in s. typhimur ...200919812899
functional and molecular characterization of pse34 encoding a type iv secretion system in salmonella enterica serotype enteritidis phage type 34.salmonella enterica serotype enteritidis infection remains a serious public health threat to humans. salmonella enteritidis phage type 4 (pt4) is a clone that has already caused a global pandemic for years. to investigate why pt34 becomes a subdominantly emerging phage type, molecular characterizations, including serotyping, pulsed-field gel electrophoresis (pfge), phage typing, and plasmid profiling, were carried out on pt34. the results indicated that relative to pt4, pt34 contained an additio ...200919817860
infected abdominal aortic aneurysm caused by nontyphoid salmonella in an immunocompromised patient with rheumatoid arthritis.nontyphoid salmonella strains are important pathogens commonly found worldwide, typically causing gastrointestinal illness. here, we report a case of a 66-yearold man with an abdominal aortic infected (or so-called mycotic) aneurysm caused by salmonella enterica subsp. enterica serovar enteritidis (s. enteritidis). he had multiple risk factors for atherosclerosis: age over 60, a long history of smoking, an 8-year history of diabetes mellitus, and a 10-year history of rheumatoid arthritis treated ...200919856069
molecular epidemiology and genetic environment of acquired bla acc-1 in salmonella enterica serotype livingstone causing a large nosocomial outbreak in tunisia.eighty-four isolates of salmonella enterica serovar livingstone were collected from patients hospitalized in a pediatric ward in sfax hospital (south tunisia). these isolates were responsible for two nosocomial outbreaks in 2000 and 2002. twenty-eight clinical isolates of s. enterica serovar livingstone were also obtained in two other tunisian hospitals in monastir (central tunisia) and tunis (north tunisia), respectively, in 2002 and 2003. pulsed-field gel electrophoresis yielded that these iso ...200919857134
ctx-m-2-producing salmonella typhimurium isolated from pediatric patients and poultry in brazil.ten salmonella enterica serovar typhimurium isolates producing ctx-m-2 extended-spectrum beta-lactamase were identified from clinical and poultry sources in two distant cities in brazil between 2003 and 2004. they included two isolates from pediatric patients and eight isolates from poultry or its environment. all isolates exhibited coresistance to non-beta-lactam antimicrobials including tetracycline and trimethoprim/sulfamethoxazole. the ctx-m-2 gene was located on transferable plasmids with s ...200919857139
beta-lactam resistance in salmonella strains isolated from retail meats in the united states by the national antimicrobial resistance monitoring system between 2002 and 2006.ampicillin-resistant (amp(r)) salmonella enterica isolates (n = 344) representing 32 serotypes isolated from retail meats from 2002 to 2006 were tested for susceptibility to 21 other antimicrobial agents and screened for the presence of five beta-lactamase gene families (bla(cmy), bla(tem), bla(shv), bla(oxa), and bla(ctx-m)) and class 1 integrons. among the amp(r) isolates, 66.9% were resistant to five or more antimicrobials and 4.9% were resistant to 10 or more antimicrobials. coresistance to ...200919854922
ceftazidime-resistant salmonella enterica, morocco. 200919861080
[serovars of salmonella enterica subspecies enterica and its antimicrobial resistance in slaughterhouse pigs].a study was carried out in order to determine the prevalence of salmonella and its serovars among porcine slaughterhouses, to evaluate the antimicrobial resistance profiles and to know the presence of class 1 integrons as possible reservoir of resistance. from a total of 386 samples from four porcine slaughterhouses of buenos aires and santa fe provinces (argentina), 93 (24.1%) salmonella enterica subspecies enterica strains were identified, 52 (55.9%) from cecal contents and 41 (44.1%) from ile ...200919831314
simultaneous enrichment of shiga toxin-producing escherichia coli o157 and o26 and salmonella in food samples using universal preenrichment broth.universal preenrichment broth (upb) was compared with modified escherichia coli broth with novobiocin (mec+n) for enrichment of shiga toxin-producing e. coli o157 and o26, and with buffered peptone water (bpw) for preenrichment of salmonella enterica. ten strains each of the three pathogens were inoculated into beef and radish sprouts following thermal, freezing, or no treatment. with regard to o157 and o26, upb incubated at 42 degrees c recovered significantly more cells from inoculated beef th ...200919833028
isolation of salmonella enterica in laying-hen flocks and assessment of eggshell contamination in france.the present investigation was conducted in conjunction with the european union baseline study for the estimation of salmonella prevalence in laying-hen flocks. it aimed at evaluating eggshell contamination in farms positive for salmonella, characterizing the genetic patterns of salmonella strains and identifying the factors associated with salmonella contamination of eggshells. for this purpose, a total of 4,200 eggs were collected from 28 positive flocks and analyzed according to draft annex d ...200919833029
a rapid screen of broth enrichments for salmonella enterica serovars enteritidis, hadar, heidelberg, and typhimurium by using an allelotyping multiplex pcr that targets o- and h-antigen alleles.salmonella continues to cause significant foodborne outbreaks, best illustrated with recent outbreaks associated with peanut butter, raw tomatoes, and serrano peppers. to ascertain the likely source of the outbreak, bacterial typing is essential to this process. while pcr has become an important detection tool for pathogens in foods, pcr can also identify strain differences by targeting gene(s) or sequences exhibiting polymorphisms or variability in its distribution within the bacterial populati ...200919833046
changes of physiological and biochemical properties of salmonella enterica serovar typhimurium by deletion of cpxr and lon genes using allelic exchange method.to construct a novel salmonella attenuated live vaccine, the cpxr and lon genes were deleted from a wild-type salmonella enterica serovar typhimurium (s. typhimurium) using allelic exchange method, resulting in s. typhimurium ck31 (deltacpxr), ck38 (deltalon), and ck111 (deltacpxr/lon). these mutated strains were grown normally, as was the wild-type strain. the biochemical properties of the mutants remained highly similar to those of the wild-type. in comparison with the wild-type, 1.5 to 3.3-fo ...200919833153
effect of x-ray treatments on inoculated escherichia coli o157: h7, salmonella enterica, shigella flexneri and vibrio parahaemolyticus in ready-to-eat shrimp.this study was conducted to evaluate the inactivation effect of x-ray treatments on escherichia coli o157: h7, salmonella enteric (s. enterica), shigella flexneri (s. flexneri) and vibrio parahaemolyticus (v. parahaemolyticus) artificially inoculated in ready-to-eat (rte) shrimp. a mixed culture of three strains of each tested pathogen was used to inoculate rte shrimp. the shrimp samples were inoculated individually with selected pathogenic bacteria then aseptically placed in sterile plastic cup ...200919835772
comparative analysis of acid resistance in listeria monocytogenes and salmonella enterica strains before and after exposure to poultry decontaminants. role of the glutamate decarboxylase (gad) system.data on the ability of chemical poultry decontaminants to induce an acid stress response in pathogenic bacteria are lacking. this study was undertaken in order to compare the survival rates in acid broths of listeria monocytogenes and salmonella enterica strains, both exposed to and not exposed to decontaminants. the contribution of the glutamate decarboxylase (gad) acid resistance system to the survival of bacteria in acid media was also examined. four strains (l. monocytogenes serovar 1/2, l. ...200919835779
rpos- and crp-dependent transcriptional control of salmonella typhi taia and hlye genes: role of environmental conditions.a novel pathogenicity island, spi-18, carries the taia-hlye operon, encoding virulence factors in salmonella typhi. to determine the effects of certain environmental conditions on the expression of these genes, beta-galactosidase assays, rt-pcr reactions, western blot analyses and measurement of hemolytic activity were performed. the conditions studied are those likely found by s. typhi during infection in the human host. we found rpos-dependent transcriptional upregulation in low ph and high os ...200919835951
multistate outbreak of salmonella infections associated with small turtle exposure, 2007-2008.turtle-associated salmonellosis was increasingly recognized in the united states during the 1960s, leading to a federal ban in 1975 on the sale of turtles <4 inches in carapace length (small turtles). although sporadic reports of turtle-associated salmonella are frequent, outbreaks are rare. in september 2007, several patients with salmonella enterica serotype paratyphi b var java infections reported recent turtle exposure. we conducted an investigation to determine the source and extent of the ...200919841114
ndp52: the missing link between ubiquitinated bacteria and autophagy.mammalian cells ubiquitinate bacteria that erroneously enter the cytosol and target these intruding microbes for destruction by autophagy. new work shows that the protein ndp52 directly binds to ubiquitinated bacteria and facilitates the assembly of an autophagic membrane that surrounds these invaders.200919841643
the synergistic activity of triclosan and ciprofloxacin on biofilms of salmonella typhimurium.triclosan is a biocide whose wide use has raised a debate about the potential benefits vs. hazards of the incorporation of antimicrobials in consumer products. the purpose of the present study was to determine whether exposure of biofilms of salmonella enterica serovar typhimurium to triclosan influences the tolerance of the bacteria towards antibiotics such as ciprofloxacin and vice versa. a synergistic antibiofilm activity was observed when the biofilms were treated with triclosan before or to ...200919843306
identification of salmonella enterica subspecies i, salmonella enterica serovars typhimurium, enteritidis and typhi using multiplex pcr.this study was designed to develop a multiplex pcr method with five specific primer pairs for the detection of salmonella spp., salmonella subspecies i, salmonella enterica serovars typhimurium, typhi and enteritidis. a multiplex pcr was constructed with five primer pairs for the detection of salmonella and pathogenic salmonella serovars, including a specific primer pair for salmonella typhi, based on the sequence comparison between genomic dna sequences of 12 salmonella strains. each primer pai ...200919843307
induction of cxc chemokine messenger-rna expression in chicken oviduct epithelial cells by salmonella enterica serovar enteritidis via the type three secretion system-1.the messenger-rna (mrna) expression of selected cytokines and chemokines in primary chicken oviduct epithelial cells (coec) was determined following in vitro infections with wild-type or type three secretion system (t3ss)-mutant salmonella enterica serovar enteritidis (se) strains. all se strains examined in this study elicited the expression of proinflammatory immune mediators including inducible nitric oxide synthase (inos), cxcli1 (k60), cxcli2 (il-8), ccli3 (k203), and ccli4 (mip-1beta). se ...200919848079
identification and characterization of a novel antibacterial peptide, avian beta-defensin 2 from ducks.in this study, a novel avian beta-defensin (avbd) was isolated from duck pancreas. the complete nucleotide sequence of the gene contained an 195 bp open reading frame encoding 64 amino acids. homology, characterization and comparison of the gene with avbd from other avian species confirmed that it was duck avbd2. the mrna expression of the gene was analyzed in 17 tissues from 21-day-old ducks. avbd2 was highly expressed in the trachea, crop, heart, bone marrow, and pancreas; moderately expressed ...200919851734
multi-immunogenic outer membrane vesicles derived from an msbb-deficient salmonella enterica serovar typhimurium mutant.to develop low endotoxic and multi-immunogenic outer membrane vesicles (omvs), a deletion mutant of the msbb gene in salmonella enterica serovar typhimurium (s. typhimurium) was used as a source of low endotoxic omv, and an expression vector of the canine parvovirus (cpv) vp2 epitope fused to the bacterial ompa protein was constructed and transformed into the salmonella deltaamsbb mutant. in a lethality test, balb/c mice injected intraperitoneally with the salmonella deltaamsbb mutant survived f ...200919884791
antimicrobial resistance genes in salmonella enterica isolates from poultry and swine in thailand.a total of 184 resistant salmonella enterica isolated from poultry and swine were investigated for the distribution of and associations between various antimicrobial resistance genes. all the isolates were screened for the presence of class 2 and 3 integrase genes and 18 resistance genes corresponding to their resistance phenotypes. none of the isolates carried class 2 and 3 integrons. the investigated resistance genes were responsible for resistance in 78% of the isolates. all the strains harbo ...200919887742
effects of allspice, cinnamon, and clove bud essential oils in edible apple films on physical properties and antimicrobial activities.essential oils (eos) derived from plants are rich sources of volatile terpenoids and phenolic compounds. such compounds have the potential to inactivate pathogenic bacteria on contact and in the vapor phase. edible films made from fruits or vegetables containing eos can be used commercially to protect food against contamination by pathogenic bacteria. eos from cinnamon, allspice, and clove bud plants are compatible with the sensory characteristics of apple-based edible films. these films could e ...200919895483
antibacterial effects of allspice, garlic, and oregano essential oils in tomato films determined by overlay and vapor-phase methods.physical properties as well as antimicrobial activities against escherichia coli o157:h7, salmonella enterica, and listeria monocytogenes of allspice, garlic, and oregano essential oils (eos) in tomato puree film-forming solutions (tpffs) formulated into edible films at 0.5% to 3% (w/w) concentrations were investigated in this study. antimicrobial activities were determined by 2 independent methods: overlay of the film on top of the bacteria and vapor-phase diffusion of the antimicrobial from th ...200919895486
cells in shearable and nonshearable regions of salmonella enterica serovar enteritidis biofilms are morphologically and physiologically distinct.cellular morphology, exopolymer chemistry, and protein expression of shearable and nonshearable fractions of salmonella enterica serovar enteritidis biofilms were examined. biofilms were grown at a laminar flow velocity of 0.07 cm.s-1 for ~120 h, resulting in biofilms with a thickness (mean +/- sd) of 43 +/- 24 microm. an empirically determined shear-inducing flow (1.33 cm.s-1) was then applied for 5 min, effectively reducing biofilm thickness by ~70% and leaving 13 +/- 6 microm of nonshearable ...200919898535
epidemic multiple drug resistant salmonella typhimurium causing invasive disease in sub-saharan africa have a distinct genotype.whereas most nontyphoidal salmonella (nts) are associated with gastroenteritis, there has been a dramatic increase in reports of nts-associated invasive disease in sub-saharan africa. salmonella enterica serovar typhimurium isolates are responsible for a significant proportion of the reported invasive nts in this region. multilocus sequence analysis of invasive s. typhimurium from malawi and kenya identified a dominant type, designated st313, which currently is rarely reported outside of africa. ...200919901036
sensitive and rapid molecular detection assays for salmonella enterica serovars typhimurium and heidelberg.salmonella enterica is a significant cause of gastroenteritis worldwide, with serovars typhimurium and heidelberg being particularly prevalent, which have broad host ranges infecting poultry, dairy animals, and humans. traditional methods used for the detection of salmonella from contaminated food products are time-consuming and labor-intensive. the aim of this study was to develop a sensitive and rapid pcr-based detection method with optimized specificity for high-throughput screening of food a ...200919903399
uptake through glycoprotein 2 of fimh(+) bacteria by m cells initiates mucosal immune response.the mucosal immune system forms the largest part of the entire immune system, containing about three-quarters of all lymphocytes and producing grams of secretory iga daily to protect the mucosal surface from pathogens. to evoke the mucosal immune response, antigens on the mucosal surface must be transported across the epithelial barrier into organized lymphoid structures such as peyer's patches. this function, called antigen transcytosis, is mediated by specialized epithelial m cells. the molecu ...200919907495
case report of pediatric gastroenteritis due to ctx-m-15 extended-spectrum beta-lactamase-producing salmonella enterica serotype enteritidis.a clinical isolate of salmonella enterica serotype enteritidis in korea was found to produce the extended-spectrum beta-lactamase ctx-m-15. the isolate was recovered in 2008 from the stool of a 3-yr-old boy with gastroenteritis. this isolate was found to be resistant to multiple drugs, including ampicillin, piperacillin, cefotaxime, ceftazidime, cefepime, and aztreonam. the resistance to cefotaxime was transferred by conjugation to recipient escherichia coli j53. the patient was eventually succe ...200919893356
identification of in vivo induced protein antigens of salmonella enterica serovar typhi during human infection.during infectious disease episodes, pathogens express distinct subsets of virulence factors which allow them to adapt to different environments. hence, genes that are expressed or upregulated in vivo are implicated in pathogenesis. we used in vivo induced antigen technology (iviat) to identify antigens which are expressed during infection with salmonella enterica serovar typhi. we identified 7 in vivo induced (ivi) antigens, which included bcfd (a fimbrial structural subunit), grxc (a glutaredox ...200919911130
genome wide evolutionary analyses reveal serotype specific patterns of positive selection in selected salmonella serotypes.the bacterium salmonella enterica includes a diversity of serotypes that cause disease in humans and different animal species. some salmonella serotypes show a broad host range, some are host restricted and exclusively associated with one particular host, and some are associated with one particular host species, but able to cause disease in other host species and are thus considered "host adapted". five salmonella genome sequences, representing a broad host range serotype (typhimurium), two host ...200919912661
improving the aoac use-dilution method by establishing a minimum log density value for test microbes on inoculated carriers.the aoac use-dilution methods, 955.14 (salmonella enterica), 955.15 (staphylococcus aureus), and 964.02 (pseudomonas aeruginosa), are used to measure the efficacy of disinfectants on hard inanimate surfaces. the methods do not provide procedures to assess log density of the test microbe on inoculated penicylinders (carrier counts). without a method to measure and monitor carrier counts, the associated efficacy data may not be reliable and repeatable. this report provides a standardized procedure ...200919916390
genomic and phenotypic variation in epidemic-spanning salmonella enterica serovar enteritidis isolates.salmonella enterica serovar enteritidis (s. enteritidis) has caused major epidemics of gastrointestinal infection in many different countries. in this study we investigate genome divergence and pathogenic potential in s. enteritidis isolated before, during and after an epidemic in uruguay.200919922635
cellular cholesterol involvement in src, pkc, and p38/jnk transduction pathways by porins.biological membranes are described as a mosaic of different domains where interactions between membrane components induce the formation of subdomains with different characteristics and functions. lipids play an important role in the formation of lipid-enriched microdomains where they dynamically associate to form platforms important for membrane protein sorting and construction of signaling complexes. cholesterol confined in lipid domains is a crucial component required by microorganisms, direct ...200919929574
toll-like receptor 4 signalling through myd88 is essential to control salmonella enterica serovar typhimurium infection, but not for the initiation of bacterial clearance.toll-like receptor-4 (tlr4) is important in protection against lethal salmonella enterica serovar typhimurium (s. typhimurium) infection. control of the early stages of sublethal s. typhimurium infection in mice depends on tlr4-dependent activation of macrophages and natural killer (nk) cells to drive an inflammatory response. tlr4 signals through the adapter proteins mal/myd88 and trif-related adaptor molecule (tram)/tir-domain-containing adaptor-inducing interferon-b (trif). in the mouse typho ...200919930040
efficacy of several vaccination programmes in commercial layer and broiler breeder hens against experimental challenge with salmonella enterica serovar enteritidis.two experiments were performed to evaluate the protective effect of various vaccination combinations given at 5 and 9 weeks of age against experimental challenge with salmonella enterica serovar enteritidis (se) phage type 4 at 12 weeks of age. in experiment 1, groups of commercial layers were vaccinated by one of the following programmes: group 1, two doses of a se bacterin (layermune se); group 2, one dose of a live salmonella enterica serovar gallinarum vaccine (cevac sg9r) followed by one do ...200919937524
a comparison of the efficacy of cleaning and disinfection methods in eliminating salmonella spp. from commercial egg laying houses.effective terminal cleaning and disinfection (c&d) is regarded as a necessary step for the elimination of salmonella spp. from laying houses. a total of 60 commercial laying houses that had housed laying flocks infected with salmonella enterica serovar enteritidis or salmonella enterica serovar typhimurium that were representative of all production systems (cage, barn, free-range) were intensively sampled immediately after c&d as well as in the follow-on flock. the procedures investigated were: ...200919937529
study of an unusual paratyphoid epornitic in canaries (serinus canaria).high mortalities in 17 canary flocks from different regions of tehran, iran, were reported. necropsy and histopathologic examination revealed necrotic hepatitis and overall congestive septicaemia in carcasses. salmonella enterica was isolated from 34 examined samples, two samples from each flock, including visceral organs of carcasses and droppings of live diseased birds. all isolates were typed as salmonella enterica serovar typhimurium by conventional serotyping. antibiotic resistance profilin ...200919937532
influence of rpos, camp-receptor protein, and ppgpp on expression of the opggh operon and osmoregulated periplasmic glucan content of salmonella enterica serovar typhimurium.a transcriptional fusion (opgg1::mudj) to the opggh operon of salmonella enterica serovar typhimurium (s. typhimurium) lt2, isolated by resistance to mecillinam, was used to study the influence of global regulators rpos, ppgpp, and camp/camp-receptor protein (crp) on expression of the opggh operon and osmoregulated periplasmic glucan (opg) content. neither high growth medium osmolarity nor absence of ppgpp or crp had important effects on opgg1::mudj expression in exponential cultures. however, u ...200919940937
some putative prebiotics increase the severity of salmonella enterica serovar typhimurium infection in mice.prebiotics are non-digestible food ingredients believed to beneficially affect host health by selectively stimulating the growth of the beneficial bacteria residing in the gut. such beneficial bacteria have been reported to protect against pathogenic infections. however, contradicting results on prevention of salmonella infections with prebiotics have been published. the aim of the present study was to examine whether s. typhimurium sl1344 infection in mice could be prevented by administration o ...200919948011
proteome of salmonella enterica serotype typhimurium grown in a low mg/ph medium.to determine the impact of a low mg(2+)/ph defined growth medium (mgm) on the proteome of salmonella enterica serotype typhimurium, we cultured s. typhimurium cells in the medium under two different conditions termed mgm shock and mgm dilution and then comparatively analyzed the bacterial cells harvested from these conditions by a global proteomic approach. proteomic results showed that mgm shock and mgm dilution differentially affected the s. typhimurium proteome. mgm shock induced a group of p ...200919953200
the salmonella spi2 effector ssei mediates long-term systemic infection by modulating host cell migration.host-adapted strains of salmonella enterica cause systemic infections and have the ability to persist systemically for long periods of time despite the presence of a robust immune response. chronically infected hosts are asymptomatic and transmit disease to naïve hosts via fecal shedding of bacteria, thereby serving as a critical reservoir for disease. we show that the bacterial effector protein ssei (also called srfh), which is translocated into host cells by the salmonella pathogenicity island ...200919956712
prevalence of chlamydia trachomatis and neisseria gonorrhoeae in hiv-seropositive patients and gonococcal antimicrobial susceptibility: an update in thailand.we surveyed the rate of chlamydial and gonococcal infections among human immunodeficiency virus (hiv)-seropositive patients in thailand as well as the current status of antimicrobial resistance of neisseria gonorrhoeae and determined the prevalence of penicillinase-producing n. gonorrhoeae (ppng) in thailand. a total of 1,158 endocervical swabs from 824 hiv-seropositive patients were collected to detect both organisms by gen-probe. the prevalences of chlamydial and gonococcal infection were 9.7 ...200919934542
size-dependent pcr inhibitory effect induced by gold nanoparticles.in this work, the effect of gold nanoparticles (aunps) with diameters of around 5, 10 and 20 nm on pcr efficiency is evaluated respectively using a real-time pcr machine. gold nanoparticles show no obvious effect on pcr at low particle concentration. when the concentration is increased, pcr inhibition is observed. at the same particle concentration, gold nanoparticles of different sizes show different inhibitory effects on pcr. it is found that taq polymerase can interact with aunps. the interac ...200919964596
evolutionary diversification of an ancient gene family (rhs) through c-terminal displacement.rhs genes are prominent features of bacterial genomes that have previously been implicated in genomic rearrangements in e. coli. by comparing rhs repertoires across the enterobacteriaceae, this study provides a robust explanation of rhs diversification and evolution, and a mechanistic model of how rhs diversity is gained and lost.200919968874
septic arthritis of the sternoclavicular joint caused by salmonella in a healthy person.the sternoclavicular (sc) joint is an unusual site for septic arthritis in healthy people. it is mostly described as affecting intravenous drug abusers. we report a rare case of sternoclavicular osteo-arthritis caused by non-typhoid salmonella in an immunocompetent person. the patient presented with general weakness, dizziness, epigastric and anterior chest pain that had persisted for one week. peptic ulcer disease was diagnosed by gastro-intestinal endoscopy. computed tomography (ct) revealed f ...200919994814
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