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structure of the heme/hemoglobin outer membrane receptor shua from shigella dysenteriae: heme binding by an induced fit mechanism.shigella dysentriae and other gram-negative human pathogens are able to use iron from heme bound to hemoglobin for growing. we solved at 2.6 a resolution the 3d structure of the tonb-dependent heme/hemoglobin outer membrane receptor shua from s. dysenteriae. shua binds to hemoglobin and transports heme across the outer membrane. the structure consists of a c-terminal domain that folds into a 22-stranded transmembrane beta-barrel, which is filled by the n-terminal plug domain. one distal histidin ...201019731368
bcl-2 regulates the onset of shiga toxin 1-induced apoptosis in thp-1 cells.shiga toxins (stxs), which are proteins expressed by the enteric pathogens shigella dysenteriae serotype 1 and some serotypes of escherichia coli, are potent protein synthesis inhibitors. stx-producing organisms cause bloody diarrhea with the potential to progress to acute renal failure and central nervous system complications. studies using animal models of these diseases have shown that stxs are major virulence factors, and purified toxins have been shown to be capable of killing many types of ...200919752028
the shigella dysenteriae serotype 1 proteome, profiled in the host intestinal environment, reveals major metabolic modifications and increased expression of invasive proteins.shigella dysenteriae serotype 1 (sd1) causes the most severe form of epidemic bacillary dysentery. we present the first comprehensive proteome analysis of this pathogen, profiling proteins from bacteria cultured in vitro and bacterial isolates from the large bowel of infected gnotobiotic piglets (in vivo). overall, 1061 distinct gene products were identified. differential display analysis revealed that sd1 cells switched to an anaerobic energy metabolism in vivo. high in vivo abundances of amino ...200919813213
the etiology of acute dysentery in the united states.1. the several standard cultures used in this study are indistinguishable -a conclusion previously reached and stated by flexner. 2. the acute dysentery of the united states is due to a bacillus indistinguishable from that obtained from the epidemics of dysentery in several other parts of the world. 3. the sporadic and the institutional outbreaks of acute dysentery are caused by the same microorganism, and this organism is identical with that causing epidemic acute dysentery. 4. the cause of acu ...190219866970
the relation of types of diarrhoea in children to strains of bacillus dysenteriae. 190619867045
the resistance of spirochetes to the action of hexamethylenetetramine derivatives and mercurial and arsenic compounds.the majority of the 76 new compounds possessed spirocheticidal powers ranging between 1: 1,000 (30) to 1:2,500 (14), while only 2 attained the power of 1:5,000, 1 of 1: 25,000, and 2 of 1: 50,000. on the other hand, 8 killed the spirochetes in a dilution of 1: 750, 10 in 1:500, 7 in 1:250. 1 in 1: 100, and 1 in 1:50. it may be mentioned that the 2 (m1, m4) of 1:50,000 and 1 (m7) of 1:25,000 belong to the mercury compounds, and that mercuric chloride kills the organisms in a dilution of 1: 100,00 ...191719868094
the survival of leptospira (spirochaeta) icterohaemorrhagiae in nature; observations concerning microchemical reactions and intermediary hosts.1. leptospira icterohaemorrhagiae is unable to grow in the urine, either with or without the addition of suitable culture ingredients, the acidity of the urine being detrimental to the growth. it survives less than 24 hours, unless the urine is neutralized or slightly alkalized, when the period of survival is somewhat longer. if suitable nutrient ingredients are added to the neutralized or slightly alkalized urine, the organism is able to grow for about 10 days, after which multiplication ceases ...191819868229
toxins and antitoxins of bacillus dysenteriae shiga.with the methods which have been described we have separated an exotoxin and an endotoxin from cultures of the shiga dysenteric bacillus. the study of the nature and effect of the poison of this microorganism is thus simplified. the two toxins are physically and biologically distinct. the exotoxin is relatively heat-labile, arises in the early period of growth, and yields an antiexotoxic immune serum. the endotoxin, on the other hand, is heat-stable, is formed in the later period of growth, and ...192019868386
divisions of the so called flexner group of dysentery bacilli.from these data it is seen that ill defined divisions of the so called flexner group exist. the divisions do not appear to be sufficiently distinct to warrant the use of separate names. to avoid confusion all mannitol-fermenting dysentery bacilli should be called bacillus dysenteriae flexner and the subdivision noted. there are two methods for this division, one by the fermentation of carbohydrates, the other by agglutination with monovalent rabbit sera. these do not coincide and one or the othe ...192019868467
studies on the phenomenon of d'herelle with bacillus dysenteriae.it has been shown that a lytic fluid for dysentery bacilli can be obtained from the peritoneum of the guinea pig by intraperitoneal inoculation of live dysentery bacilli, and that the lytic action of such a fluid is not strictly specific, but that it exerts a group action on the dysentery-colon-typhoid group of bacilli. a lytic fluid with similar effects was obtained from a child dying of flexner dysentery infection, and an anti-colon bacillus lytic fluid from a child who died of intussusception ...192119868572
separation of the toxins of bacillus dysenteriae shiga.by the suppression, through anaerobiosis, of the exotoxin-producing activity of bacillus dysenteriae shiga a pure endotoxin is produced directly from the culture. the duality of the poison of shiga bacillus is further substantiated by studies on the diffusion of exotoxin, or neurotoxin, and endotoxin, or enterotoxin, by means of collodion sacs, implanted intraabdominally in rabbits or placed in vitro.192319868758
the multiplication of bacteriophage in vivo and its protective effect against an experimental infection with shigella dysenteriae.1. anti-shiga bacteriophage injected into the general circulation can multiply in the brain of mice infected intracerebrally with shigella dysenteriae. 2. under proper conditions, the injection of active bacteriophage into the general circulation can protect mice against an otherwise fatal intracerebral infection with shigella dysenteriae. 3. the protection so induced appears to depend upon the early establishment of a high bacteriophage level in the infected animal.194319871319
preparation and properties of shiga toxin and toxoid.1. shigella dysenteriae (shiga) can, under the proper cultural conditions, produce a soluble toxin which is independent of the specific somatic polysaccharide antigen. a method is described for the rapid production of this toxin by an avirulent r variant of this organism. 2. the amount of bacterial protoplasm synthesized, and the yield of toxin produced, are very much increased when the culture is grown under conditions which favor aerobic metabolism and which do not permit accumulation of organ ...194619871559
caspase-8-mediated cleavage of bid and protein phosphatase 2a-mediated activation of bax are necessary for verotoxin-1-induced apoptosis in burkitt's lymphoma cells.verotoxin (vt-1) is a cytotoxin, produced by shigella dysenteriae type 1 or by shiga toxin-producing escherichia coli, which binds specifically to globotriaosylceramide (gb3). this glycosphingolipid is a b cell differentiation antigen (gb3/cd77) strongly expressed on burkitt's lymphoma cells. we have previously shown that, in these cells, vt-1 induces apoptosis via a caspase- and mitochondria-dependent pathway. in this report, we provide new insights into this signal transduction pathway. first, ...201019895884
adaptive immune responses during shigella dysenteriae type 1 infection: an in vitro stimulation with 57 kda major antigenic omp in the presence of anti-cd3 antibody.an effort was made to understand the role of the 57 kda major antigenic fraction of shigella outer membrane protein (omp) in the presence of t-cell antigen receptor in activation of adaptive immune responses of the cell mediated immune (cmi) restored patients. the expression of hla-dr/cd4 out of cd3(+) t-cells was significantly dominant over the hla-dr/cd8 and comparable to unstimulated cells of infected or healthy controls. cd4(+) t-cell activation together with hla-dr is associated with the ex ...201019915959
characterization of wrss2 and wrss3, new second-generation virg(icsa)-based shigella sonnei vaccine candidates with the potential for reduced reactogenicity.live, attenuated shigella vaccine candidates, such as shigella sonnei strain wrss1, shigella flexneri 2a strain sc602, and shigella dysenteriae 1 strain wrsd1, are attenuated principally by the loss of the virg(icsa) protein. these candidates have proven to be safe and immunogenic in volunteer trials and in one study, efficacious against shigellosis. one drawback of these candidate vaccines has been the reactogenic symptoms of fever and diarrhea experienced by the volunteers, that increased in a ...201019932216
inactivated and subunit vaccines to prevent shigellosis.shigellosis remains a formidable disease globally, with children of the developing world bearing the greatest number of infections. the need for an affordable, safe and efficacious vaccine has persisted for decades. vaccines to prevent shigellosis can be divided into living and nonliving approaches. several nonliving shigella vaccines are currently at different stages of development and show substantial promise. outlined here is an overview of multiple nonliving vaccine technologies, highlightin ...200919943764
a motile culture of bacillus dysenteriae. 190419971613
modification of bacillus dysenteriae after cultivation in agglutinating serum. 190619971738
the isolation of bacillus dysenteriae from stools. 191019971981
antibodies against recombinant shiga toxin subunit b neutralize shiga toxin toxicity in hela cells.shigella dysenteriae type 1 and escherichia coli o157:h7 produce shiga toxin 1 (stx) and shiga toxin1 (stx1), respectively and these two toxins are almost identical. e. coli o157:h7 is the major cause of diarrhea-associated hemolytic uremic syndrome. stx and stx1 are ab5 type of toxin with a molecular weight of 70 kda, comprising an enzymaticaly-active a subunit (32 kda) and five receptor-binding b subunits (7.7 kda). in this study dna fragment (289 bp, gene bank accn no. ef685161) coding for b ...201020044923
diarrhea associated hemolytic uremic syndrome: a 3-year picu experience from nepal. 200920072865
selective deletion of cd8(+) cells upregulated by caspases-1 via il-18 in mice immunized with major outer membrane protein of shigella dysenteriae 1 following infection.introduction: mucosal lymphoid changes were observed in cryopreserved rectal tissues obtained from balb/c mice infected with shigella dysenteriae 1, immunized with 57-kda major antigenic outer membrane protein, and infection after immunization. discussion: our data suggested that caspase-3 is downregulated in cd4(+) cells of immunized balb/c mice following infection with substantial increased expression of interleukin (il)-2 and interferon (ifn)-gamma, while caspase-1 is upregulated in cd8(+) ce ...201020084439
chaperonin activity modulates codon adaptation. 201020087337
groel dependency affects codon usage--support for a critical role of misfolding in gene evolution.it has recently been suggested that the use of optimal codons limits mistranslation-induced protein misfolding, yet evidence for this remains largely circumstantial. in contrast, molecular chaperones have long been recognized to play crucial roles in misfolding prevention and remedy. we propose that putative error limitation in cis can be elucidated by examining the interaction between codon usage and chaperoning processes. using escherichia coli as a model system, we find that codon optimality ...201020087338
a piglet model of acute gastroenteritis induced by shigella dysenteriae type 1.the lack of a standardized laboratory animal model that mimics key aspects of human shigellosis remains a major obstacle to addressing questions about pathogenesis, screening therapeutics, and evaluation of vaccines.201020136414
characterisation of pathogenic bacteria in a uasb-polishing pond system using molecular techniques.molecular techniques have been commonly used to detect and quantify pathogenic bacteria in food, clinical and environmental samples, but in wastewater treatment plants few studies have been carried out. this work applied pcr with a specific set of primers to investigate pathogenic bacteria in a wastewater plant comprised of a uasb reactor followed by polishing ponds. in addition, in-situ hybridisation technique (fish) was used to estimate the abundance of escherichia coli in the system. accordin ...201020150719
a challenge model for shigella dysenteriae 1 in cynomolgus monkeys (macaca fascicularis).shigella dysenteriae type 1 can cause devastating pandemics with high case fatality rates; a vaccine for shigella is unavailable currently. because of the risks associated with performing challenge studies with wild-type s. dysenteriae 1 in human clinical trials to advance vaccine development, an improved nonhuman primate model is needed urgently. in the present study, cynomolgus macaques (macaca fascicularis) were challenged with various doses of s. dysenteriae 1 strain 1617 to establish a dose ...201020158950
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
evaluation of antimicrobial activity of the stem bark of cylicodiscus gabunensis (mimosaceae).ethyl acetate (ea) extract of the stem bark of cylicodiscus gabunensis (cg) was analysed phytochemically and evaluated for its antimicrobial activity against 17 pathogenic species isolated from patient: escherichia coli, klebsiella pneumoniae, shigella dysenteriae, shigella flexneri, morganella morganii, proteus vulgaris, proteus mirabilis, salmonella typhi, citrobacter freundii, enterobacter cloacae, enterobacter agglomerans, staphylococcus aureus, streptococcus feacalis, pseudomonas aeruginosa ...200620162076
structure, biological functions and applications of the ab5 toxins.ab(5) toxins are important virulence factors for several major bacterial pathogens, including bordetella pertussis, vibrio cholerae, shigella dysenteriae and at least two distinct pathotypes of escherichia coli. the ab(5) toxins are so named because they comprise a catalytic a-subunit, which is responsible for disruption of essential host functions, and a pentameric b-subunit that binds to specific glycan receptors on the target cell surface. the molecular mechanisms by which the ab(5) toxins ca ...201020202851
induction of apoptosis by shiga toxins.shiga toxins comprise a family of structurally and functionally related protein toxins expressed by shigella dysenteriae serotype 1 and multiple serotypes of escherichia coli. while the capacity of shiga toxins to inhibit protein synthesis by catalytic inactivation of eukaryotic ribosomes has been well described, it is also apparent that shiga toxins trigger apoptosis in many cell types. this review presents evidence that shiga toxins induce apoptosis of epithelial, endothelial, leukocytic, lymp ...201020210553
separation and concentration of a thermolabile precipitinogen from shigella dysenteriae (shiga). 194720247165
experimental infection of mice with shigella dysenteriae and modification of the infection by means of antitoxic and antibacterial sera. 194720251869
characterisation of multidrug-resistant salmonella typhimurium 4,[5],12:i:- dt193 strains carrying a novel genomic island adjacent to the thrw trna locus.in 2006, monophasic, multidrug-resistant salmonella enterica spp. enterica serovar 4,[5],12:i:- strains appeared as a novel serotype in germany, associated with large diffuse outbreaks and increased need for hospitalisation. the emerging 4,[5],12:i:- strains isolated from patients in germany belong mainly to phage type dt193 according to the anderson phage typing scheme for s. typhimurium (stm) and exhibit at least a tetra-drug resistance. the strains have been shown to harbour stm-specific gifs ...201020303825
ulcerative colitis due to bacillus dysenteriae, simulating pernicious anaemia. 192220314110
infection and intoxication of macacus mulatta with shigella dysenteriae (shiga). 194720344285
antibiotics for the treatment of dysentery in children.ciprofloxacin, ceftriaxone and pivmecillinam are the antibiotics currently recommended by the world health organization (who) for the treatment of dysentery in children; yet there have been no reviews of the clinical effectiveness of these antibiotics in recent years.201020348130
global transcriptional response of macrophage-like thp-1 cells to shiga toxin type 1.shiga toxins (stxs) are bacterial cytotoxins produced by the enteric pathogens shigella dysenteriae serotype 1 and some serotypes of escherichia coli that cause bacillary dysentery and hemorrhagic colitis, respectively. to date, approaches to studying the capacity of stxs to alter gene expression in intoxicated cells have been limited to individual genes. however, it is known that many of the signaling pathways activated by stxs regulate the expression of multiple genes in mammalian cells. to ex ...201020351145
antimicrobial resistence of shigella species isolated during 2004 and 2005 from selected sites in zimbabwe.to determine the predominant serotype and antibiotic sensitivity pattern of shigella isolates during 2004 and 2005 in zimbabwe.200620353132
isolation of bacteria from mouse caecal samples and description of bacteroides sartorii sp. nov.caecal samples from wild-type and tnf(deltaare) mice were cultured on selective media containing bile salts, amino acids or casein macro-peptides. twenty-two strains were isolated and identified by 16s rrna gene sequencing. twenty-one strains showed >98% similarity to known bacteria (blautia spp., clostridium innocuum, enterococcus spp., escherichia coli, lactobacillus murinus, parabacteroides goldsteinii and shigella dysenteriae). one additional isolate, strain a-c2-0, was a new bacterium. the ...201020369227
antibacterial effect of the bioactive compound beauvericin produced by fusarium proliferatum on solid medium of wheat.to obtain the bioactive compound beauvericin (bea), fusarium proliferatum cect 20569 was grown on a solid medium of wheat, utilizing the technique of the solid state fermentation (ssf), being this mycotoxin purified by high performance liquid chromatography (hplc) with a reverse phase semi-preparative column using as the mobile phase acetonitrile/water in gradient condition. the purity of the bea was verified by analytical hplc and liquid chromatography tandem mass spectrometry (lc/ms-ms). the p ...201020371252
synthesis, antimicrobial and antiinflammatory activity of 2,5-disubstituted-1,3,4-oxadiazoles.in the present study, 2,5-disubstituted-1,3,4-oxadiazoles (3a-o) have been synthesized by the condensation of 4-methoxybenzohydrazide (1) with different aromatic acids (2a-o) in presence of phosphoryl chloride. the structural assignment of this compound (3a-o) has been made on the basis of elemental analysis, uv, ir, (1)h nmr and mass spectral data. the synthesized compounds were screened for their in vitro growth inhibiting activity against different strains of bacteria and fungi viz., staphylo ...200820390080
bacillus dysenteriae of flexner in relation to asylum dysentery. 190820474361
an investigation of bacillus dysenteriae (sonne type iii). 192820474980
epidemic dysentery in the nursing staff due to bacillus dysenteriae sonne. 193120475098
a thermolabile substance of shigella dysenteriae shiga. 194620475737
changing species distribution and antimicrobial susceptibility pattern of shigella over a 29-year period (1980-2008).we studied changes in species distribution and antimicrobial resistance patterns of shigella during 1980-2008, using the diarrhoeal diseases surveillance system of dhaka hospital of icddr,b. in hospitalized patients shigella prevalence decreased steadily from 8-12% in the 1980s to 3% in 2008. endemic s. flexneri was the most commonly isolated species (54%). epidemic s. dysenteriae type 1 had two peaks in 1984 and 1993, but was not found after 2000, except for one case in 2004. the therapeutic op ...201120478088
immunochemical studies of shigella flexneri 2a and 6, and shigella dysenteriae type 1 o-specific polysaccharide-core fragments and their protein conjugates as vaccine candidates.there is no licensed vaccine for the prevention of shigellosis. our approach to the development of a shigella vaccines is based on inducing serum igg antibodies to the o-specific polysaccharide (o-sp) domain of their lipopolysaccharides (lps). we have shown that low molecular mass o-sp-core (o-spc) fragments isolated from shigella sonnei lps conjugated to proteins induced significantly higher antibody levels in mice than the full length o-sp conjugates. this finding is now extended to the o-spc ...201020542498
agap2 regulates retrograde transport between early endosomes and the tgn.the retrograde transport route links early endosomes and the tgn. several endogenous and exogenous cargo proteins use this pathway, one of which is the well-explored bacterial shiga toxin. adp-ribosylation factors (arfs) are approximately 20 kda gtp-binding proteins that are required for protein traffic at the level of the golgi complex and early endosomes. in this study, we expressed mutants and protein fragments that bind to arf-gtp to show that arf1, but not arf6 is required for transport of ...201020551179
novel family of antimicrobial peptides from the skin of rana shuchinae.so far numerous antimicrobial peptides have been characterized from amphibians. in this work, a new family of antimicrobial peptides, named shuchin, was purified and characterized from skin secretions of the frog, rana shuchinae that lives in freezing mountains. totally two members of shuchin (shuchin 1 and 2) were identified with the amino acid sequence of nalsmprnkcnralmcfg and nalssprnkcdrasscfg, respectively. cdnas encoding shuchins were cloned from the skin cdna library of r. shuchinae. the ...201020553780
production of antimicrobial silver nanoparticles in water extracts of the fungus amylomyces rouxii strain ksu-09.a fungal strain, ksu-09, isolated from the roots of date palm (phoenix dactylifera), was identified as amylomyces rouxii based on sequence analysis of the internal transcribed spacer (its) region of its rrna genes. mycelia-free water extracts obtained from mycelium suspended in water for 72h facilitated the production of stable, predominantly monodispersed and spherical silver nanoparticles (agnps) in the size range of 5-27nm upon addition of 1mm silver nitrate, as determined by the xrd, afm and ...201020619641
shiga toxin b subunits induce vwf secretion by human endothelial cells and thrombotic microangiopathy in adamts13-deficient mice.diarrhea-associated hemolytic uremic syndrome (d+hus) is the most common cause of acute renal failure among children. renal damage in d+hus is caused by shiga toxin (stx), which is elaborated by shigella dysenteriae and certain strains of escherichia coli, in north america principally e coli o157:h7. recent studies demonstrate that stx also induces von willebrand factor (vwf) secretion by human endothelial cells and causes thrombotic thrombocytopenic purpura, a disease with similarities to d+hus ...201020644116
glycan encapsulated gold nanoparticles selectively inhibit shiga toxins 1 and 2.shiga toxins (stx) released by escherichia coli o157:h7 and shigella dysentriae cause life-threatening conditions that include hemolytic uremic syndrome (hus), kidney failure, and neurological complications. cellular entry is mediated by the b-subunit of the ab(5) toxin, which recognizes cell surface glycolipids present in lipid raft-like structures. we developed gold glyconanoparticles that present a multivalent display similar to the cell surface glycolipids to compete for these toxins. these ...201020669970
control of coliform bacteria detected from diarrhea associated patients by extracts of moringa oleifera.the aims of this study were to determine the total population of coliform bacteria in the samples collected from diarrhea associated patients from the local area of bangladesh and to examine the antibacterial efficacy of leaf extracts of moringa oleifera (moringaceae) against the isolated coliform bacteria. the coliform bacteria detected in these samples by some microbial-biochemical tests such as escherichia coli, shigella dysenteriae, salmonella sp., enterobacter sp., klebsiella pneumoniae and ...201020677603
production of glycoprotein vaccines in escherichia coli.conjugate vaccines in which polysaccharide antigens are covalently linked to carrier proteins belong to the most effective and safest vaccines against bacterial pathogens. state-of-the art production of conjugate vaccines using chemical methods is a laborious, multi-step process. in vivo enzymatic coupling using the general glycosylation pathway of campylobacter jejuni in recombinant escherichia coli has been suggested as a simpler method for producing conjugate vaccines. in this study we descri ...201020701771
association of water-borne diseases morbidity pattern and water quality in parts of ibadan city, nigeria.occurrence of diarrhoea and other water-borne diseases in cities of developing countries has been on the increase over the decades largely due to unsafe water, inadequate sanitation and poor hygiene among human population. this study examined the relationship between the spatial pattern of water-borne diseases vis-a-vis water quality in parts of ibadan city in nigeria. data on 1334 cases of various water-borne diseases was collected from eight public hospitals with catchments covering the study ...200920734698
plasmon-induced inactivation of enteric pathogenic microorganisms with ag-agi/al2o3 under visible-light irradiation.the plasmon-induced photocatalytic inactivation of enteric pathogenic microorganisms in water using ag-agi/al(2)o(3) under visible-light irradiation was investigated. the catalyst was found to be highly effective at killing shigella dysenteriae (s. dysenteriae), escherichia coli (e. coli), and human rotavirus type 2 wa (hrv-wa). its bactericidal efficiency was significantly enhanced by hco(3)(-) and so(4)(2-) ions, which are common in water, while phosphate had a slightly positive effect on the ...201020734989
attempts to produce a safe and effective bacillus dysenteriae (shiga) vaccine for prophylactic purposes. 191620768027
transmembrane bax inhibitor motif containing (tmbim) family proteins perturbs a trans-golgi network enzyme, gb3 synthase, and reduces gb3 biosynthesis.globotriaosylceramide (gb3) is a well known receptor for shiga toxin (stx), produced by enterohemorrhagic escherichia coli and shigella dysenteriae. the expression of gb3 also affects several diseases, including cancer metastasis and fabry disease, which prompted us to look for factors involved in its metabolism. in the present study, we isolated two cdnas that conferred resistance to stx-induced cell death in hela cells by expression cloning: ganglioside gm3 synthase and the cooh terminus regio ...201020837469
characterization and antimicrobial activity of 4-(β-d-glucopyranosyl-1→4-α-l-rhamnopyranosyloxy)-benzyl thiocarboxamide; a novel bioactive compound from moringa oleifera seed extract.antimicrobial activity of crude seed extract of moringa oleifera was investigated by thin layer chromatography bioassay against escherichia coli, pseudomonas aeruginosa, staphylococcus aureus, cladosporium cladosporioides, and penicillium sclerotigenum; most of them were prominently inhibited by an isolate with r(f) 0.92-0.96. characterization and identification of the extract revealed the occurrence of three bioactive compounds: 4-(α-l-rhamnopyranosyloxy)benzyl isothiocyanate, methyl n-4-(α-l-r ...201020941575
the detoxification by acetylation of soluble antigens from shigella dysenteriae and e. typhosa. 194620984596
preparation and evaluation of an irradiated toxoid from the toxin of shigella dysenteriae. 194621001448
a thermolabile substance of shigella dysenteriae shiga. 194621013070
the detoxification by acetylation of soluble antigens from shigella dysenteriae (shiga) and e. typhosa. 194621017963
the preparation of a potent toxin of shigella dysenteriae (shiga) on a semi-synthetic medium and its use for the preparation of an alum-precipitated toxoid. 194621026411
[the immunizing properties of the phago-resistent strains of shigella dysenteriae]. 194521027462
[rapid detection of shigella dysenteriae by pcr assay].based on the invasive plasmid antigen h gene (ipah) of s. dysenteriae, one pair of specific primers was designed for pcr assays in this study. the concentrations of dntp, mg2+ and primer, dosage of taq dna polymerase, annealing temperature and circulating parameter in the pcr amplification system were optimized. in this way, a rapid and stable method of pcr assay for the detection of s. dysenteriae was established. the specificity and sensitivity of pcr were also analyzed. the detection limits o ...201021033439
research progress in shigella in the postgenomic era.gram-negative, facultative intracellular anaerobes of the genus shigella, the principal etiologic agents of shigellosis, continue to pose a threat to public health. shigellosis causes 1.1 million deaths with over 164 million annual cases. the shigella spp. can be divided into four serogroups: shigella dysenteriae, shigella flexneri, shigella boydii and shigella sonnei. the completion of seven shigella genome sequences of representative strains from each of the shigella species has introduced an ...201021046319
[detection and drug resistance analysis of extended-spectrum beta-lactamases-producing shigella in pediatric patients].to investigate the occurrence and drug resistance of extended-spectrum beta-lactamases (esbls)-producing strains of shigella in pediatric patients, so as to provide information for clinical treatment.201021055309
preparation and evaluation of an irradiated toxoid from the toxin of shigella dysenteriae. 194621064736
the structure of the escherichia coli o148 lipopolysaccharide core region and its linkage to the o-specific polysaccharide.recently it was demonstrated that shigella dysenteriae type 1, a cause of severe dysentery epidemics, gained its o-specific polysaccharide (o-sp) from escherichia coli o148. the o-sps of these bacteria differ only by a galactose residue in the repeat unit of s. dysenteriae type 1 in place of a glucose residue in e. coli o148. herein, we analyzed the core structure and its linkage to the o-sp in e. coli o148 lps. both were found to be identical to those of s. dysenteriae type 1 structures, furthe ...201021074753
development of a quantitative rt-pcr assay to examine the kinetics of ribosome depurination by ribosome inactivating proteins using saccharomyces cerevisiae as a model.ricin produced by the castor bean plant and shiga toxins produced by pathogenic escherichia coli (stec) and shigella dysenteriae are type ii ribosome inactivating proteins (rips), containing an enzymatically active a subunit that inhibits protein synthesis by removing an adenine from the α-sarcin/ricin loop (srl) of the 28s rrna. there are currently no known antidotes to shiga toxin or ricin, and the ability to screen large chemical libraries for inhibitors has been hindered by lack of quantitat ...201021098653
thrombotic microangiopathies: thrombotic thrombocytopenic purpura / hemolytic uremic syndrome.thrombotic microangiopathies (tmas) are pathological conditions characterized by generalized microvascular occlusion by platelet thrombi, thrombocytopenia, and microangiopathic hemolytic anemia. two typical phenotypes of tmas are hemolytic- uremic syndrome (hus) and thrombotic thrombocytopenic purpura (ttp). other disorders occasionally present with similar manifestations. depending on whether renal or brain lesions prevail, two pathologically indistinguishable but somehow clinically different d ...201021103695
facile synthesis and antibacterial activity of naturally occurring 5-methoxyfuroflavone.a convenient synthesis of 5-methoxyfuroflavone (6, pongaglabol methyl ether), a constituent of some pongamia or millettia genus, was achieved by starting from 2,4-dihydroxy-6-methoxyacetophenone via a chalcone precursor, followed by treatment with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (ddq). this five-step reaction (total yield: 21.6%) is more facile with that of previously utilized procedures using each different starting material. antibacterial activities of the above compound and its prec ...201021139271
convergent synthesis of a common pentasaccharide corresponding to the o-antigen of escherichia coli o168 and shigella dysenteriae type 4.a convenient synthetic strategy of the common acidic pentasaccharide repeating unit corresponding to the o-antigen of enterotoxigenic e. coli o168 and shigella dysenteriae type 4 has been successfully developed. a stereoselective [2 + 3] block glycosylation method has been exploited to get the target pentasaccharide derivative. most of the synthetic intermediates were solid and prepared in high yields from commercially available reducing sugars following a series of protection-deprotection react ...201021181263
imperatorin a furocoumarin inhibits periplasmic cu-zn sod of shigella dysenteriae their by modulates its resistance towards phagocytosis during host pathogen interaction.shigella dysenteriae continues to be a major health problem, which leads to death, due to diarrhoea and dysentery, predominantly in children below the age of 5. bacterial invasion of the colonic epithelium leads to severe inflammation together with bacterial dissemination generates abscesses and ulcerations. periplasmic copper, zinc super oxide dismutase of shigella protects it from exogenous superoxide produced by host, during its invasion. hence, in present study an attempt was made to study t ...201021194882
synthesis and evaluation of a class of new coumarin triazole derivatives as potential antimicrobial agents.a series of new coumarin-based 1,2,4-triazole derivatives were designed, synthesized and evaluated for their antimicrobial activities in vitro against four gram-positive bacteria (staphylococcus aureus, mrsa, bacillus subtilis and micrococcus luteus), four gram-negative bacteria (escherichia coli, proteus vulgaris, salmonella typhi and shigella dysenteriae) as well as three fungi (candida albicans, saccharomyces cerevisiae and aspergillus fumigatus) by two-fold serial dilution technique. the bio ...201021215620
shiga toxin and its use in targeted cancer therapy and imaging.shiga and the shiga-like toxins are related protein toxins produced by shigella dysenteriae and certain strains of escherichia coli. these toxins are composed of two non-covalently attached, modular parts: the a moiety (stxa) containing the enzymatically active a1 fragment, and the non-toxic, pentameric binding moiety (stxb). stx binds specifically to the glycosphingolipid globotriaosylceramide (gb3) at the surface of target cells and is then internalized by endocytosis. subsequently, in toxin-s ...201121255370
antibacterial, antifungal and cytotoxic activities of amblyone isolated from amorphophallus campanulatus.to assess the in vitro antibacterial, antifungal and cytotoxic activities of amblyone, a triterpenoid isolated from amorphophallus campanulatus (roxb).200821264161
efficient screening of a novel antimicrobial peptide from jatropha curcas by cell membrane affinity chromatography.a novel method named cell membrane affinity chromatography was used to screen antimicrobial peptides from jatropha curcas . a cationic antimicrobial peptide (kvflglk, jcpep7) was successfully isolated and identified. antimicrobial assays indicated that jcpep7 was active against the tested microorganisms ( salmonella typhimurium atcc 50013, shigella dysenteriae atcc 51302, pseudomonas aeruginosa atcc 27553, staphylococcus aureus atcc 25923, bacillus subtilis atcc 23631, and streptococcus pneumoni ...201121268582
isolation and partial characterisation of a novel lectin from aegle marmelos fruit and its effect on adherence and invasion of shigellae to ht29 cells.lectins are a class of ubiquitous proteins/glycoproteins that are abundantly found in nature. lectins have unique carbohydrate binding property and hence have been exploited as drugs against various infectious diseases. we have isolated one such novel lectin from the fruit pulp of aegle marmelos. the isolated lectin was partially characterised and its effect against shigella dysenteriae infection was evaluated. the isolated lectin was found to be a dimeric protein with n-acetylgalactosamine, man ...201121283697
mixed infections of vibrio cholerae o1 ogawa el tor with shigella dysenteriae.mixed infections caused by enteric pathogens such as bacteria, virus, protozoa and helminthes were reported in different literatures. this report also describes the co-infections caused by vibrio cholerae o1 ogawa el tor with shigella dysenteriae in a patient. a 36-year-old man was admitted in fatemeh zahra hospital of bushehr iran with fever, vomiting and dysentery. his stool sample was cultured, for identification purposes tcbs, xld and other media were used. v. cholerae and s. dysenteriae wer ...201021313886
virulence of environmental stenotrophomonas maltophilia serologically cross-reacting with shigella-specific antisera.this research involved an environmental strain of stenotrophomonas maltophilia which has been reported to produce serological cross-reactivity with shigella dysenteriae type 8 specific antisera. since clinical diagnosis of shigellosis is largely based on culture and serology, the investigation was aimed at in vivo and in vitro virulence comparison between the culturally similar environmental s. maltophilia isolate and the reference s. dysenteriae strains. the findings of this study revealed the ...201021313916
testing meningococcal vaccines for mitogenicity and superantigenicity.proteins with intrinsic mitogenic properties are widely represented in prokaryotes, such as in different streptococcus species (1-3), candida albicans (4), and eikenella corrodens (5). specifically, several bacterial porins of escherichia coli, shigella dysenteriae, salmonella typhimurium, fusobacterium nucleatum, and pathogenic neisseria species have been shown to induce nonspecific proliferation of lymphocytes (6-12).200121336757
a comparison of disease caused by shigella and campylobacter species: 24 months community based surveillance in 4 slums of karachi, pakistan.despite the efforts of the international community diarrheal diseases still pose a major threat to children in children less than five years of age. bacterial diarrhea has also emerged as a public health concern due to the proliferation of drug resistant species in many parts of the world. there is a paucity of population-based data about the incidence of shigellosis and campylobacter infections in pakistan. we report country specific results for shigella diarrhea that were derived from a multic ...201121338955
rapid emergence of third-generation cephalosporin resistance in shigella sp. isolated in andaman and nicobar islands, india.shigellosis is a major cause of diarrheal diseases among children in andaman & nicobar islands, india, which have a population of 350,000 people, including settlers from mainland india and 6 indigenous tribes. from the last one-and-half decade, we have been monitoring the species distribution and emergence of antibiotic resistance among the isolates of shigella. the circulating shigella strains have been found rapidly acquiring resistance to a wide spectrum of antibiotics. the recent data indica ...201121352076
fabrication of silver nanoparticles doped in the zeolite framework and antibacterial activity.using the chemical reduction method, silver nanoparticles (ag nps) were effectively synthesized into the zeolite framework in the absence of any heat treatment. zeolite, silver nitrate, and sodium borohydride were used as an inorganic solid support, a silver precursor, and a chemical reduction agent, respectively. silver ions were introduced into the porous zeolite lattice by an ion-exchange path. after the reduction process, ag nps formed in the zeolite framework, with a mean diameter of about ...201121383858
antibacterial activity of the enniatin b, produced by fusarium tricinctum in liquid culture, and cytotoxic effects on caco-2 cells.the enniatins (ens) are bioactive compounds of hexadepsipeptidic structure produced by several strains of fusarium sp. the en b was purified from extracts of fusarium tricinctum growth on liquid culture of potato dextrose broth (pdb), using a semipreparative liquid chromatography (lc) followed by an analytical lc. the purity and the structure of the isolated compound were confirmed by the determination of the extinction coefficient and with electrospray ionization-mass spectrometry (esi-ms) stud ...201121417626
antimicrobial susceptibilities of enteric bacterial pathogens isolated in kathmandu, nepal, during 2002-2004.the prevalence and antimicrobial susceptibility patterns of the bacterial enteropathogens vibrio cholerae, salmonella species and shigella species were investigated.201121444984
genetic diversity and antibiotic resistance in shigella dysenteriae and shigella boydii strains isolated from children aged <5 years in egypt.summarydiversity within shigella dysenteriae (n=40) and shigella boydii (n=30) isolates from children living in egypt aged <5 years was investigated. shigella-associated diarrhoea occurred mainly in summer months and in children aged <3 years, it commonly presented with vomiting and fever. serotypes 7 (30%), 2 (28%), and 3 (23%) accounted for most of s. dysenteriae isolates; 50% of s. boydii isolates were serotype 2. s. dysenteriae and s. boydii isolates were often resistant to ampicillin, chlor ...201121470441
zidovudine (azt) has a bactericidal effect on enterobacteria and induces genetic modifications in resistant strains.the spread of multiresistant bacteria increases the need for new antibiotics. the observation that some nucleoside analogues have antibacterial activity led us to further investigate the antimicrobial activity and resistance of zidovudine (azt). we determined the minimum inhibition concentration (mic), studied time-kill curves, induced resistant bacteria and sequenced the gene for thymidine kinase. we demonstrate that azt has a bactericidal effect on some enterobacteria. however, azt could induc ...201121494911
synthesis, antibacterial activity and quantum-chemical studies of novel 2-arylidenehydrazinyl-4-arylthiazole analogues.a new series of 2-arylidenehydrazinyl-4-arylthiazole derivatives (2a-k) was designed and synthesized through a rapid, simple, and efficient methodology in excellent isolated yield. these compounds were screened for in vitro antimicrobial activities against eight bacteria, e.g. bacillus cereus, staphylococcus aureus, bacillus subtilis, bacillus megaterium, pseudomonas aeruginosa, shigella dysenteriae, salmonella typhi, escherichia coli, and three fungi e.g. aspergillus oryzae, candida albicans, a ...201121532194
development of a new guinea-pig model of shigellosis.shigellosis is a major form of bacillary dysentery caused by shigella spp. to date, there is no suitable animal model to evaluate the protective efficacy of vaccine candidates against this pathogen. here, we describe a successful experimental shigellosis in the guinea-pig model, which has shown the characteristic features of human shigellosis. this model yielded reproducible results without any preparatory treatment besides cecal ligation. in this study, guinea-pigs were discretely infected with ...201121539623
genetic characteristics and changing antimicrobial resistance among shigella spp isolated from hospitalized diarrhoeal patients in kolkata, india.to study the prevalence pattern and trends in the phenotypic and genetic characteristics of shigellae, we tested 212 isolates isolated from diarrhoeal patients admitted at the infectious diseases hospital, kolkata, india from november 2007 to october 2009. prevalence of shigella spp was more in more than 5 years age group (69%) than the children >5 years age group (31%). serotypes 2a, 3a and untypable isolates of the subtype s. flexneri were frequently detected. increase in the isolation of s. s ...201121659504
in vivo versus in vitro protein abundance analysis of shigella dysenteriae type 1 reveals changes in the expression of proteins involved in virulence, stress and energy metabolism.shigella dysenteriae serotype 1 (sd1) causes the most severe form of epidemic bacillary dysentery. quantitative proteome profiling of shigella dysenteriae serotype 1 (sd1) in vitro (derived from lb cell cultures) and in vivo (derived from gnotobiotic piglets) was performed by 2d-lc-ms/ms and apex, a label-free computationally modified spectral counting methodology.201121702961
differential response of the human renal proximal tubular epithelial cell line hk-2 to shiga toxin types 1 and 2.shiga toxins (stxs) are expressed by the enteric pathogens shigella dysenteriae serotype 1 and certain serotypes of escherichia coli. stx-producing bacteria cause bloody diarrhea with the potential to progress to acute renal failure. stxs are potent protein synthesis inhibitors and are the primary virulence factors responsible for renal damage that may follow diarrheal disease. we explored the use of the immortalized human proximal tubule epithelial cell line hk-2 as an in vitro model of stx-ind ...201121708996
shiga toxins induce autophagy leading to differential signalling pathways in toxin-sensitive and toxin-resistant human cells.the bacterial virulence factors shiga toxins (stxs) are expressed by shigella dysenteriae serotype 1 and certain escherichia coli strains. stxs are protein synthesis inhibitors and induce apoptosis in many cell types. stxs induce apoptosis via prolonged endoplasmic reticulum stress signalling to activate both extrinsic and intrinsic pathways in human myeloid cells. studies have shown that autophagy, a lysosome-dependent catabolic process, may be associated with activation of pro-survival or deat ...201121722286
viral-associated thrombotic microangiopathies.thrombotic microangiopathies encompass a group of disorders characterized by microangiopathic hemolytic anemia, thrombocytopenia associated with hyaline thrombi (comprised primarily of platelet aggregates in the microcirculation), and varying degrees of end-organ failure. many primary (genetic) and secondary etiological predisposing factors have been described-namely pregnancy, autoimmune disorders, cancer, drugs and antineoplastic therapy, bone marrow transplantation/solid organ transplantation ...201121727765
lipopolysaccharide core structures and their correlation with genetic groupings of shigella strains; a novel core variant in shigella boydii type 16.bacteria shigella, the cause of shigellosis, evolved from intestinal bacteria escherichia coli. based on structurally diverse o-specific polysaccharide chains of the lipopolysaccharides (o-antigens), three from four shigella species are subdivided into multiple serotypes. the central oligosaccharide of the lipopolysaccharide called core is usually conserved within genus but five core types called r1-r4 and k-12 have been recognized in e. coli. structural data on the shigella core are limited to ...201121752864
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