Publications

TitleAbstractYear
Filter
PMID(sorted descending)
Filter
cephalosporin-resistant shigella flexneri over 9 years (2001-09) in india.to determine the pattern and antimicrobial resistance genes of cephalosporin resistance in shigella flexneri and shigella dysenteriae over 9 years.201222410619
in vitro adherence patterns of shigella serogroups to bovine recto-anal junction squamous epithelial (rse) cells are similar to those of escherichia coli o157.the aims of this study were to determine whether shigella species, which are human gastrointestinal pathogens, can adhere to cattle recto-anal junction squamous epithelial (rse) cells using a recently standardized in vitro adherence assay, and to compare their adherence patterns with that of escherichia coli o157. shigella dysenteriae (serogroup a), s. flexneri (serogroup b), s. boydii (serogroup c), and s. sonnei (serogroup d) were tested in adherence assays using both rse and hep-2 cells, in t ...201222401271
effect of bovine lactoferrin on the minimum inhibitory concentrations of ampicillin and trimethoprim-sulfamethoxazole for clinical shigella spp. strains.here, we determined the effect of bovine lactoferrin (blf) on the minimum inhibitory concentration (mic) of ampicillin and trimethoprim-sulfamethoxazole in shigella . using a microdilution method, the mic was determined in the presence or absence of bovine lactoferrin (10 mg/ml) on 88 shigella strains (56 shigella flexneri , 15 shigella boydii , 13 shigella sonnei , and 4 shigella dysenteriae ) previously isolated from peruvian children <2 years old. a fold change of 2 or more in mic values was ...201222397495
differential expression of gastric muc5ac in colonic epithelial cells: tff3-wired il1 β/akt crosstalk-induced mucosal immune response against shigella dysenteriae infection.an understanding of the signaling mechanism(s) that regulate the differential expression of gastric mucin muc5ac in colonic epithelial cells would contribute significantly to investigations of its role in colonic mucosa infected with the bacterial pathogen shigella dysenteriae. here we show that s. dysenteriae-sinduced expression of interleukin-1β upregulates muc2 expression and the differential expression of muc5ac. differential expression of muc5ac involves crosstalk between interleukin-1β and ...201222389405
antimicrobial-resistant shigella infections from iran: an overlooked problem?in this study, we wanted to assess the level of antimicrobial resistance, the presence of genes encoding resistance to cephalosporins and plasmid-mediated quinolone resistance (pmqr), and genetic relatedness among shigella isolates obtained from iranian patients.201222345385
bacteria and their toxins tamed for immunotherapy.bacterial toxins share the ability to enter host cells to target various intracellular proteins and to modulate host immune responses. over the last 20 years, toxins and their mutated variants, as well as live attenuated bacteria, have been exploited for vaccination and immunotherapy of various infectious, malignant and autoimmune diseases. the ability of bordetella pertussis adenylate cyclase toxin to translocate its adenylate cyclase domain across the host cell membrane, as well as the pathway ...201222339216
antibacterial effect and cytotoxicity of beta-1,3-1, 4-glucanase from endophytic bacillus subtilis swb8.we studied the antibiotic activity and selective cytotoxicity of beta-1,3-1,4-glucanase from endophytic bacillus subtilis swb8.201122260051
comparison of microcalorimetric fingerprint profiles of lonicerae japonicae flos and lonicerae flos.to compare the microcalorimetric fingerprint profiles of lonicerae japonicae flos (lj.f) and lonicerae flos (l.f), microcalormietry was applied to find the heat change regularity of bacillus shigae (b. shigae) metabolism affected by lj.f and l.f (we choose lonicera macranthoides hand.-mazz in this paper) with different concentrations. the thermogenic curves and thermodynamics parameters were investigated as evaluation index, and then the date of experiment was studied by similarity analysis. all ...201122242460
neurological manifestations of shigellosis in children in southwestern iran. 201122115119
Differential host immune responses to epidemic and endemic strains of Shigella dysenteriae type I.Shigella dysenteriae type 1 causes devastating epidemics in developing countries with high case-fatality rates in all age-groups. The aim of the study was to compare host immune responses to epidemic (T2218) and endemic strains of S. dysenteriae type 1. Shigellacidal activity of serum from rabbits immunized with epidemic or endemic strains, S. dysenteriae type 1-infected patients, and healthy adult controls from Shigella-endemic and non-endemic regions was measured. Immunogenic cross-reactivity ...201122106748
up-regulation of muc2 and il-1β expression in human colonic epithelial cells by shigella and its interaction with mucins.the entire gastrointestinal tract is protected by a mucous layer, which contains complex glycoproteins called mucins. muc2 is one such mucin that protects the colonic mucosa from invading microbes. the initial interaction between microbes and mucins is an important step for microbial pathogenesis. hence, it was of interest to investigate the relationship between host (mucin) and pathogen interaction, including shigella induced expression of muc2 and il-1β during shigellosis.201122073249
shiga toxins: intracellular trafficking to the er leading to activation of host cell stress responses.despite efforts to improve hygenic conditions and regulate food and drinking water safety, the enteric pathogens, shiga toxin-producing escherichia coli (stec) and shigella dysenteriae serotype 1 remain major public health concerns due to widespread outbreaks and the severity of extra-intestinal diseases they cause, including acute renal failure and central nervous system complications. shiga toxins are the key virulence factors expressed by these pathogens mediating extra-intestinal disease. de ...201022069648
shiga toxin is transported into the nucleoli of intestinal epithelial cells via a carrier-dependent process.shiga toxin (stx) produced by the invasive shigella dysenteriae serotype 1 (s. dysenteriae1) causes gastrointestinal and kidney complications. it has been assumed that stx is released intracellularly after enterocyte invasion by s. dysenteriae1. however, there is little information about stx distribution inside s. dysenteriae1-infected enterocytes. here, we use intestinal epithelial t84 cells to characterize the trafficking of stx delivered into the cytosol, in ways that mimic aspects of s. dyse ...201022069640
Exploration of in vitro time point quantitative evaluation of newly synthesized benzimidazole and benzothiazole derivatives as potential antibacterial agents.Present communication deals with the in vitro time point quantitative antibacterial evaluation of newly synthesized 1,2-disubstituted benzimidazoles (3a-p) and 2-substituted benzothiazoles (5a-h) against Gram-positive bacteria Staphylococcus aureus, Bacillus cereus, and Gram-negative bacteria Vibrio cholerae, Shigella dysenteriae and Escherichia coli. These compounds were synthesized under mild reaction conditions using Al(2)O(3)-Fe(2)O(3) nanocrystals as heterogeneous catalyst. Bio-evaluation s ...201122047695
antibacterial characteristics and activity of water-soluble chitosan derivatives prepared by the maillard reaction.the antibacterial activity of water-soluble chitosan derivatives prepared by maillard reactions against staphylococcus aureus, listeria monocytogenes, bacillus cereus, escherichia coli, shigella dysenteriae, and salmonella typhimurium was examined. relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. in addition, it was found that the susceptibility of the test organisms to the water-solu ...201121989311
dipstick test for rapid diagnosis of shigella dysenteriae 1 in bacterial cultures and its potential use on stool samples.we describe a test for rapid detection of s. dysenteriae 1 in bacterial cultures and in stools, at the bedside of patients.201121984895
live attenuated shigella dysenteriae type 1 vaccine strains overexpressing shiga toxin b subunit.shigella dysenteriae serotype 1 (s. dysenteriae 1) is unique among the shigella species and serotypes in the expression of shiga toxin which contributes to more severe disease sequelae and the ability to cause explosive outbreaks and pandemics. s. dysenteriae 1 shares characteristics with other shigella species, including the capability of causing clinical illness with a very low inoculum (10 to 100 cfu) and resistance to multiple antibiotics, underscoring the need for efficacious vaccines and t ...201121969003
The iron-responsive Fur/RyhB regulatory cascade modulates the Shigella outer membrane protease IcsP.Actin-based motility is central to the pathogenicity of the intracellular bacterial pathogen Shigella. Two Shigella outer membrane proteins, IcsA and IcsP, are required for efficient actin-based motility in the host cell cytoplasm, and the genes encoding both proteins are carried on the large virulence plasmid. IcsA triggers actin polymerization on the surface of the bacterium, leading to the formation of an actin tail that allows both intra- and intercellular spread. IcsP, an outer membrane pro ...201121859852
recombinant shiga toxin b subunit elicits protection against shiga toxin via mixed th type immune response in mice.shigella dysenteriae is the causative agent of the third commonest bacterial disease for childhood diarrhoea and responsible for millions of deaths per year. it produces potent toxin termed shiga toxin which is listed in category b biological warfare agent of cdc, usa. earlier we have reported production of recombinant shiga toxin b subunit that produced antibodies which neutralized shiga toxin toxicity in hela cells. in the present study, we have evaluated the immunomodulatory potential of rstx ...201121856355
the effect of quercus castaneifolia extract on pathogenic enteric bacteria.the family of enterobacteriaceae is a major group of gram negative bacteria, some of these microorganisms are pathogen and could cause disease mainly gastroenteritis. recently, due to drug resistant nature of these bacteria specially in developing countries treatment of the patient considered as important investigate. quercus castaneifolia is a native plant of yasuj province in iran, which the people who living in this area consume the fruit of this plant for treatment of enteric disease. hence, ...201121827865
analysis of distribution and significance of simple sequence repeats in enteric bacteria shigella dysenteriae sd197.we have explored the possible role of ssr density in genome to generate biological information. in our study, we have checked the ssr (simple sequence repeats) status in virulent and non virulent genes of enteric bacteria to see whether the ssrs distribution contributes to virulence. the genome, plasmid and virulent genes sequences in fasta format were downloaded from ncbi genbank and vfdb. the sequences were subjected to ssr analysis using software tool ssr.exe. the resulting data was pasted in ...201121814393
a live noninvasive shigella dysenteriae 1 strain induces homologous protective immunity in a guinea pig colitis model.a noninvasive live transconjugant shigella hybrid (ltsh?stx) strain was constructed from a shiga toxin gene deleted mutant of shigella dysenteriae 1 by introducing a plasmid vector ppr1347 that carried a lipopolysaccharide biosynthesis gene (rfb and rfc) of salmonella typhimurium. in guinea pigs, four successive oral administrations of ltsh?stx showed complete protection against rectal challenge with wild type s. dysenteriae 1 strain. exponential increase of the serum igg and iga titer against l ...201121806676
pathogenic bacteria prime the induction of toll-like receptor signalling in human colonic cells by the gal/galnac lectin carbohydrate recognition domain of entamoebahistolytica.in mixed intestinal infections with entamoeba histolytica trophozoites and enteropathogenic bacteria, which are wide-spread in areas of endemic amebiasis, interaction between the pathogens could be an important factor in the occurrence of invasive disease. it has been reported that exposure of human colonic cells to enteropathogenic bacteria increased trophozoite adherence to the cells and their subsequent damage. we report here that the carbohydrate recognition domain (crd) of the amebic gal/ga ...201121787776
anti-enteric bacterial activity and phytochemical analysis of the seed kernel extract of mangifera indica linnaeus against shigella dysenteriae (shiga, corrig.) castellani and chalmers.to evaluate the phytochemical and anti-bacterial efficacy of the seed kernel extract of mangifera indica (m. indica) against the enteropathogen, shigella dysenteriae (s. dysenteriae), isolated from the diarrhoeal stool specimens.201121771473
molecular identification of bacteria by total sequence screening: determining the cause of death in ancient human subjects.research of ancient pathogens in ancient human skeletons has been mainly carried out on the basis of one essential historical or archaeological observation, permitting specific pathogens to be targeted. detection of ancient human pathogens without such evidence is more difficult, since the quantity and quality of ancient dna, as well as the environmental bacteria potentially present in the sample, limit the analyses possible. using human lung tissue and/or teeth samples from burials in eastern s ...201121765907
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
preparation and evaluation of an irradiated toxoid from the toxin of shigella dysenteriae. 194621064736
[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
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
[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
[the immunizing properties of the phago-resistent strains of shigella dysenteriae]. 194521027462
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 detoxification by acetylation of soluble antigens from shigella dysenteriae (shiga) and e. typhosa. 194621017963
a thermolabile substance of shigella dysenteriae shiga. 194621013070
preparation and evaluation of an irradiated toxoid from the toxin of shigella dysenteriae. 194621001448
the detoxification by acetylation of soluble antigens from shigella dysenteriae and e. typhosa. 194620984596
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
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
attempts to produce a safe and effective bacillus dysenteriae (shiga) vaccine for prophylactic purposes. 191620768027
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
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
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
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
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
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
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
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
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
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
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
a thermolabile substance of shigella dysenteriae shiga. 194620475737
epidemic dysentery in the nursing staff due to bacillus dysenteriae sonne. 193120475098
an investigation of bacillus dysenteriae (sonne type iii). 192820474980
bacillus dysenteriae of flexner in relation to asylum dysentery. 190820474361
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
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
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
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
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
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
infection and intoxication of macacus mulatta with shigella dysenteriae (shiga). 194720344285
ulcerative colitis due to bacillus dysenteriae, simulating pernicious anaemia. 192220314110
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
experimental infection of mice with shigella dysenteriae and modification of the infection by means of antitoxic and antibacterial sera. 194720251869
separation and concentration of a thermolabile precipitinogen from shigella dysenteriae (shiga). 194720247165
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
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
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
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
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
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 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
Displaying items 201 - 300 of 4425