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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
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
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
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
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
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
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 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
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
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
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
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
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
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
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
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
neurological manifestations of shigellosis in children in southwestern iran. 201122115119
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
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
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
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
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
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
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
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
survival of salmonella typhi and shigella dysenteriae in dehydrated infant formula.powdered infant formula has previously been linked to the transmission of various bacterial pathogens in infants resulting in life-threatening disease and death. survival studies of 2 common foodborne pathogens, salmonella enterica serovar typhi and shigella dysenteriae, in powdered infant formula have not been previously studied despite the potentially devastating consequences from ingestion of these organisms, particularly by newborns, in case of a natural or deliberate contamination event. th ...201122417504
regulation of cytokine and chemokine expression by the ribotoxic stress response elicited by shiga toxin type 1 in human macrophage-like thp-1 cells.shiga toxins (stxs) are cytotoxins produced by the enteric pathogens shigella dysenteriae serotype 1 and shiga toxin-producing escherichia coli (stec). stxs bind to a membrane glycolipid receptor, enter cells, and undergo retrograde transport to ultimately reach the cytosol, where the toxins exert their protein synthesis-inhibitory activity by depurination of a single adenine residue from the 28s rrna component of eukaryotic ribosomes. the depurination reaction activates the ribotoxic stress res ...201222431646
sequential use of ultraviolet light and chlorine for reclaimed water disinfection.several disinfection processes of ultraviolet (uv), chlorine or uv followed by chlorine were investigated in municipal wastewater according to the inactivation of escherichia coli, shigella dysenteriae and toxicity formation. the uv inactivation of the tested pathogenic bacteria was not affected by the quality of water. it was found that the inactivated bacteria were obviously reactivated after one day in dark. fluorescent light irradiation increased the bacteria repair. the increase of uv dosag ...201122432254
novel genomic tools for specific and real-time detection of biothreat and frequently encountered foodborne pathogens.the bacterial genera escherichia, salmonella, shigella, vibrio, yersinia, and francisella include important food safety and biothreat agents. by extensive mining of the whole genome and protein databases of diverse, closely and distantly related bacterial species and strains, we have identified novel genome regions, which we utilized to develop a rapid detection platform for these pathogens. the specific genomic targets we have identified to design the primers in francisella tularensis subsp. tu ...201222488053
evaluation of sample preparation methods for maldi-tof ms identification of highly dangerous bacteria.to propose a universal workflow of sample preparation method for the identification of highly pathogenic bacteria by maldi-tof ms.201222512320
phytochemical screening, cytotoxicity and antibacterial activities of two bangladeshi medicinal plants.the objectives of the present study were to investigate phytochemical screening and to assay cytotoxicity and antibacterial activities of ethanolic extracts of leaves of two medicinal plants, aglaonema hookerianum schott (family: araceae) and lannea grandis engl. (family: anacardiaceae) available in bangladesh. the brine shrimp lethality bioassay showed that the ethanolic extracts of aglaonema hookerianum and lannea grandis possessed cytotoxic activities with lc50 5.25 (microg ml(-1)) and 5.75 ( ...201122518935
an escherichia coli cell membrane chromatography-offline lc-tof-ms method for screening and identifying antimicrobial peptides from jatropha curcas meal protein isolate hydrolysates.a novel, simple, and rapid method, named cell membrane affinity extraction (cmae)-offline liquid chromatography time-of-flight mass spectrometry (lc-tof-ms) was developed for screening and identifying antimicrobial peptides from jatropha curcas meal protein isolate hydrolysates (jcmpih) obtained by proteolytic enzyme (pepsin, trypsin, protamex, neutrase, flavourzyme, papain, alcalase, and acid protease) hydrolysis. a cationic antimicrobial peptide (cailthkr, jcpep8) was successfully isolated and ...201222522648
the effects of the carboxyl-terminus amino acids of the shiga toxin b-subunit on retrograde transport.the shiga toxin b-subunit (stxb), from the enteric pathogen, shigella dysenteriae, is responsible for the attachment of its receptor, globotriaosylceramide (gb3), and navigates the retrograde pathway from the plasma membrane to the endoplasmic reticulum (er). in this study, in order to demonstrate the role of carboxyl-terminus (c-terminus/al) amino acids of the b-fragment on the retrograde transport speed and the retrograde transport pathway, stxb was modified by site-directed mutagenesis and by ...201222552548
antimicrobial potency of the leaf - stalk extract of curcuma longa (linn).the methanolic extract of the leaf-stalk of curcuma longa linn, was tested for its minimum inhibitor concentration (mic) against gram positive-staphylococcus aureus, bacillus pumilus, bacillus subtilis, klebsiella pnemoniae, bacillus cereus, streptococcus pneumoniae, lactobacillus arabinosus and gram negative e.coli, shigella dysenteriae, shigella sonnei, shigella boydii, salmonella typhimurium, proteus mirabilis, and vibrio cholerae strains, further, the ones of inhibition produced by the crude ...200022557005
antimicrobial activity of the mycotoxin citrinin obtained from the fungus penicillium citrinum.the mycotoxin citrinin was obtained from the fungus penicillium citrinum. it was tested for it's minimum inhibitory concentration (mic) against some gram positive strains viz. staphylococcus aureus, bacillus pumilus, bacillus subtillis, bacillus cereus, klebsiella pneumoniae, streptococcus pneumoniae, lactobacillus arabinosus and gram negative strains e.coli, shigella dysenteriae, shigella sonnei, shigella boydii, salmonella typhimurium, proteus mirabilis and vibrio cholerae. further the zones o ...200222557053
antimicrobial action of the leaf extract of lagerstroemia parviflora roxb.the benzene extract of the leaves of lagerstroemia paviflora roxb was tested for its minimum inhibitory concentration (mic) against gram positive staphylococcus aureus, bacillus subtilis, bacillus cereus, klebsiella pneumoniae, streptococcus pneumoniae, lactobacillus arabinosus and gram negative strains e.coli, shigella dysenteriae, shigella sonnei, shigella boydii, salmonella typhimurium, proteus mirabilis and vibrio cholerae. further the zones of inhibition produced by the crude extract agains ...200222557054
comparison of minimum inhibitory concentration of water soluble extracts of eugenia jambolana lam. (fam. myrtaceae) barks of different ages on dysentery and diarrhoea forming micro - organisms.a preliminary investigations was carried out to study the antibacterial activity of the water soluble extracts of five and ten years old barks of eugenia jambolana lam. (fam. myrtaceae) on dysentery and diarrhoea forming micro organisms. it was observed that the barks of young plants have a better inhibitory effect on micro - organisms like salmonella viballerup, shigella dysenteriae 10, shigella boydii 5, sgigella dysenteriae 2.198522557509
haemolytic uraemic syndrome during shigellosis.haemolytic uraemic syndrome (hus), which is comprised of the triad of haemolytic anemia, thrombocytopenia and renal insufficiency, occurs in about 13% of dysenteric patients with shigellosis due to shigella dysenteriae type 1 (sd1) infections, who are mostly children less than five years old in africa and asia. with a case-fatality rate of about 36%, it is the leading cause of death in sd1 outbreaks. research suggests that shiga toxin and lipopolysaccharide from the causative bacteria play roles ...201222579556
investigations of antimicrobial activity of some cameroonian medicinal plant extracts against bacteria and yeast with gastrointestinal relevance.resistance against antibiotics of many bacteria is accumulating. therefore, searches for new substances with antimicrobial activity have become an urgent necessity. medicinal plants are frequently used in popular medicine as remedies for many infectious diseases (intestinal infection, malaria, tuberculosis, etc.).201222583961
antimicrobial effects of psidium guajava extract as one mechanism of its antidiarrhoeal action.a morphine-like spasmolytic action (not naloxone reversible; involving the inhibition of acetylcholine release) and also effects on the transmural transport of electrolytes (na(+) and k(+)) and water have been reported as possible modes of the antidiarrhoeal action of polar fractions of psidium guajava leaf extractives. the objective for this study was to verify if the reported modes of the antidiarrhoeal action should be broadened to include direct antimicrobial actions on some of the more comm ...199922589684
detection of toxigenic vibrio cholerae with new multiplex pcr.vibrio cholerae (v. cholerae) is the etiological agent of epidemic cholera. in recent years, cholera has become endemic in different regions of the world. traditional culture and microscopic methods are considered the standard for the diagnosis of v. cholerae. however, these methods require days for confirmation. therefore, molecular methods that may be used for the sensitive, accurate, and rapid analysis of v. cholerae are urgently needed.201222632601
synthetic oligosaccharides as tools to demonstrate cross-reactivity between polysaccharide antigens.escherichia coli o148 is a nonencapsulated enterotoxigenic (etec) gram negative bacterium that can cause diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome in humans. the surface-exposed o-specific polysaccharide (o-sp) of the lipopolysaccharide of this bacterium is considered both a virulence factor and a protective antigen. it is built up of the linear tetrasaccharide repeating unit [3)-α-l-rhap-(1→2)-α-d-glcp-(1→3)-α-d-glcnacp-(1→3)-α-l-rhap-(1→] differing from that of the o-sp of s ...201222713129
report: studies on antibacterial activity of some traditional medicinal plants used in folk medicine.ethanolic extracts of eight medicinal plants commonly used in folk medicine were tested for their antibacterial activity against four gram positive strains (bacillus subtilis, staphylococcus aureus, staphylococcus epidermidis and, streptococcus pneumoniae) and six gram negative strains (escherichia coli, proteus vulgaris, proteus mirabilis. salmonella typhi para a, salmonella typhi para b and shigella dysenteriae) that were obtained from different pathological laboratories located in karachi, pa ...201222713958
structure based virtual screening of novel inhibitors against multidrug resistant superbugs.pathogenic microorganisms are persistently expressing resistance towards present generation antibiotics and are on the verge of joining the superbug family. recent studies revealed that, notorious pathogens such as salmonella typhi, shigella dysenteriae and vibrio cholerae have acquired multiple drug resistance and the treatment became a serious concern. this necessitates an alternative therapeutic solution. present study investigates the utility of computer aided method to study the mechanism o ...201222715312
multicenter evaluation of a sequence-based protocol for subtyping shiga toxins and standardizing stx nomenclature.when shiga toxin-producing escherichia coli (stec) strains emerged as agents of human disease, two types of toxin were identified: shiga toxin type 1 (stx1) (almost identical to shiga toxin produced by shigella dysenteriae type 1) and the immunologically distinct type 2 (stx2). subsequently, numerous stec strains have been characterized that express toxins with variations in amino acid sequence, some of which confer unique biological properties. these variants were grouped within the stx1 or stx ...201222760050
outer membrane vesicles of shigella boydii type 4 induce passive immunity in neonatal mice.like most other gram-negative bacteria, shigella releases outer membrane vesicles (omvs) into the surrounding environment during growth. in this study, we have exploited omvs of shigella as a protective immunogen in a mice model against shigellosis. distinctive vesicle secretion was noticed from different shigella strains. among them, shigella boydii type 4 (bch612) was secreting relatively higher amounts. we immunized female adult mice orally with 32 μg of purified shigella boydii type 4 (bch61 ...201222762732
shiga toxin in enterohemorrhagic e.coli: regulation and novel anti-virulence strategies.enterohemorrhagic escherichia coli (ehec) are responsible for major outbreaks of bloody diarrhea and hemolytic uremic syndrome (hus) throughout the world. the mortality associated with ehec infections stems from the production and release of a potent shiga toxin (stx) by these bacteria. stx induces cell death in endothelial cells, primarily in the urinary tract, causing hus. stx was first described in shigella dysenteriae serotype i by kiyoshi shiga and was discovered later in ehec. multiple env ...201222919672
shiga toxins.shiga toxins are virulence factors produced by the bacteria shigella dysenteriae and certain strains of escherichia coli. there is currently no available treatment for disease caused by these toxin-producing bacteria, and understanding the biology of the shiga toxins might be instrumental in addressing this issue. in target cells, the toxins efficiently inhibit protein synthesis by inactivating ribosomes, and they may induce signaling leading to apoptosis. to reach their cytoplasmic target, shig ...201222960449
hemolytic-uremic syndrome in asir region.hemolytic-uremic syndrome (hus) is a worldwide disease and a common cause of acute renal failure in childhood. recently the number of cases in our area seems to be increasing.199623008549
phytochemical screening and antimicrobial activity of coccinia cordifolia l. plant.the medicinal plant, coccinia cordifolia l. was analyzed for its chemical composition. the antimicrobial activities of the methanol, water, ethanol and ethyl acetate extracts of coccinia cordifolia l. plant were evaluated against some gram positive bacteria (sarcina lutea, bacillus subtilis and staphylococcus aureus), gram negative bacteria (salmonella typhi, shigella dysenteriae and escherichia coli) and fungi (candida albicans, aspergillus niger and penicillium notatum). chemical analysis show ...201223009991
haemolytic-uraemic syndrome as a sequela of diarrhoeal disease.haemolytic-uraemic syndrome (hus) is a serious sequela of diarrhoea and results in a high mortality rate. this systematic review aimed at estimating the proportion of hus cases that are linked to prior infection due to shiga toxin-producing escherichia coli (stec) or shigella dysenteriae type 1. a systematic review of the existing literature was done to identify cohort and case-control studies that examined the relationship between stec and s. dysenteriae type 1 and hus. after screening 2,516 ar ...201223082627
structural studies of the o-antigen polysaccharide from escherichia coli o115 and biosynthetic aspects thereof.the structure of the o-antigen polysaccharide (ps) of escherichia coli o115 has been investigated using a combination of component analysis and 1d and 2d nuclear magnetic resonance (nmr) spectroscopy experiments. the repeating unit of the o-antigen was elucidated using the o-deacetylated ps and has the following branched pentasaccharide structure: →3)[β-l-rhap-(1 → 4)]-β-d-glcpnac-(1 → 4)-α-d-galpa-(1 → 3)-α-d-manp-(1 → 3)-β-d-glcpnac-(1→. cross-peaks of low intensity, corresponding to a β-l-rha ...201323193180
phage inactivation of foodborne shigella on ready-to-eat spiced chicken.shigellosis, also called bacillary dysentery, is an infectious disease caused by shigella species, including shigella flexneri, shigella dysenteriae, shigella sonnei, and shigella boydii. infection with s. flexneri can result in epidemics, and shigella-contaminated food is often the source of infection, such as ready-to-eat spiced chicken and duck. therefore, we investigated the ability of shigella phages to inhibit pathogenic shigella spp. in ready-to-eat spiced chicken. food samples were inocu ...201323243250
hemolytic uremic syndrome associated with clostridium difficile infection.we report 3 cases of clostridium difficile-associated hemolytic uremic syndrome (hus) with biopsy proven renal thrombotic microangiopathy. two patients with acute renal failure were kidney transplants recipients whereas the third patient developed renal failure in the native kidneys. the presentation was preceded by acute diarrhea and stool. clostridium difficile toxin was detected in all the 3 patients. stool studies were negative for escherichia coli, shigella dysenteriae and other enteric pat ...201423320969
modification in media composition to obtain secretory production of stxb-based vaccines using escherichia coli.shiga toxin b-subunit (stxb) from shigella dysenteriae targets in vivo antigen to cancer cells, dendritic cells (dc) and b cells, which preferentially express the globotriaosylceramide (gb3) receptor. this pivotal role has encouraged scientists to investigate fusing stxb with other clinical antigens. due to the challenges of obtaining a functional soluble form of the recombinant stxb, such as formation of inclusion bodies during protein expression, scientists tend to combine stxb with vaccine ca ...201323329470
crystal structure, antibacterial and cytotoxic activities of a new complex of bismuth(iii) with sulfapyridine.a new complex of bi(iii) and sulfapyridine was synthesized and characterized by elemental analysis, atomic absorption spectrometry, conductivity analysis, electrospray ionization mass spectrometry (esi-ms), infrared spectroscopy, and single crystal x-ray diffraction methods. the antimicrobial and the cytotoxic activities of the compound were investigated. elemental and conductivity analyses are in accordance to the formulation [bicl₃(c₁₁h₁₁n₃o₂s)₃]. the structure of the complex reveals a distort ...201323348999
recombinant salmonella vaccination technology and its application to human bacterial pathogens.salmonella enterica is a gram-negative intracellular bacterial pathogen which causes salmonellosis in humans and animals. during the past several decades, extensive studies have shown that the attenuated salmonella vaccine vector is an optimal vehicle for delivering passenger antigens to mucosal sites to induce humoral, cellular, and mucosal immunity. this immunity leads to protection against challenges with the wild-type pathogens from which the passenger antigens were derived. a myriad of stud ...201323360265
monitoring of growth and physiological activities of biofilm during succession on polystyrene from activated sludge under aerobic and anaerobic conditions.the present research work monitored the successive biofilm development and its catabolic role in the degradation of polystyrene (ps). ps material was artificially colonized with biofilm by incubating it with activated sludge under aerobic and anaerobic conditions. biofilm formation was monitored by gravimetric weight analysis, spectrophotometric absorbance technique, heterotrophic plate count, and scanning electron microscopy under aerobic and anaerobic conditions. the wet weight (1.59 and 1.17  ...201323361646
shigella strains are not clones of escherichia coli but sister species in the genus escherichia.shigella species and escherichia coli are closely related organisms. early phenotyping experiments and several recent molecular studies put shigella within the species e. coli. however, the whole-genome-based, alignment-free and parameter-free cvtree approach shows convincingly that four established shigella species, shigella boydii, shigella sonnei, shigella felxneri and shigella dysenteriae, are distinct from e. coli strains, and form sister species to e. coli within the genus escherichia. in ...201223395177
antidiarrheal, antioxidant and antimicrobial activities of the musa sapientum seed.musa sapientum (m.sapientum) commonly known as 'banana' is widely used in bangladeshi folk medicine for the treatment of various ailments including diarrhea. hence, the present study was designed to investigate antidiarrheal, antioxidant and antibacterial potential of the methanolic extract of m.sapientum seed (mmss). the extract was studied for antidiarrheal property using castor oil and magnesium sulfate induced diarrheal model and charcoal induced gastrointestinal motility test in mice. total ...201123407989
recombinant heat shock protein 60 (hsp60/groel) of salmonella enterica serovar typhi elicits cross-protection against multiple bacterial pathogens in mice.heat shock proteins (hsps) or stress proteins are recognized as protective antigens against a wide range of bacterial diseases. conservation of hsps across different life forms also appears to contribute to the antigenicity of these proteins. due to their high sequence homology, there exists an immunological cross-recognition between different bacterial species. in the present study, we evaluated the efficacy of recombinant groel of salmonella enterica serovar typhi as a vaccine candidate agains ...201323474314
comparative analysis of the genomes of shigella dysenteriae type 2 & type 7 isolates.the four species of the genus shigella, namely, s. dysenteriae , s. flexneri, s. boydii and s. sonnei cause a wide spectrum of illness from watery diarrhoea to severe dysentery. genomes of these four species show great diversity. in this study, noti, xbai or i-ceui restriction enzyme digested genomes of two shigella dysenteriae isolates belonging to the serotypes 2 and 7 were extensively analyzed to find their relatedness, if any, with the whole genome sequenced strains of s. dysenteriae type 1 ...201323481068
multiplexed immunoassay to assess shigella-specific antibody responses.infection with shigella spp. results in bacillary dysentery and a systemic and mucosal antibody response. the immune response is directed at multiple antigens, including lps and the invasin plasmid antigen (ipa) proteins, and is capable of conferring short-term, serotype-specific protection. both live-attenuated and several subunit vaccine approaches have focused on inducing a pronounced mucosal immune response directed to the same antigens recognized after natural infection. traditionally, shig ...201323583496
antioxidant, antibacterial and cytotoxic effects of the phytochemicals of whole leucas aspera extract.to investigate the antioxidant, antibacterial and cytotoxic activity of whole leucas aspera (labiatae) (l. aspera) alcoholic extract.023620850
a study of in vitro antibacterial activity of lanthanides complexes with a tetradentate schiff base ligand.to establish the antibacterial activity of lanthanides complexes with a tetradentate schiff base ligand l.201323646299
changing emergence of shigella sero-groups in bangladesh: observation from four different diarrheal disease hospitals.shigellosis continues to be a public health challenge for developing countries, including bangladesh. the aim of the study is to demonstrate recent changes in shigella sero-groups and their geographical diversity.201323658619
multi-serotype outer membrane vesicles of shigellae confer passive protection to the neonatal mice against shigellosis.recently, we have demonstrated, immunization of adult female mice with outer membrane vesicles (omvs) of shigella boydii type 4 protected their offspring passively from shigellosis. in our present study, we have advanced our research by formulating multi-serotype outer membrane vesicles (momvs), mixing the omvs of shigella dysenteriae 1 δstx, shigella flexneri 2a, 3a and 6, s. boydii type 4 and shigella sonnei to achieve a broad spectrum protection against shigellosis. adult mice were immunized ...201323684822
rna-mediated thermoregulation of iron-acquisition genes in shigella dysenteriae and pathogenic escherichia coli.the initiation, progression and transmission of most bacterial infections is dependent upon the ability of the invading pathogen to acquire iron from each of the varied environments encountered during the course of a natural infection. in total, 95% of iron within the human body is complexed within heme, making heme a potentially rich source of host-associated nutrient iron for invading bacteria. as heme is encountered only within the host, pathogenic bacteria often regulate synthesis of heme ut ...201323704938
molecular cloning and biologically active production of ipad n-terminal region.shigella is known as pathogenic intestinal bacteria in high dispersion and pathogenic bacteria due to invasive plasmid antigen (ipa). so far, a number of ipa proteins have been studied to introduce a new candidate vaccine. here, for the first time, we examined whether the n-terminal region of ipad(72-162) could be a proper candidate for shigella vaccine. initially, the dna sequence coding n-terminal region was isolated by pcr from shigella dysenteriae type i and cloned into pet-28a expression ve ...201323731655
serological cross-reaction between o-antigens of shigella dysenteriae type 4 and an environmental escherichia albertii isolate.an environmental freshwater bacterial isolate, dm104, appearing as shigella-like colonies on selective agar plates was found to show strong and specific serological cross-reactivity with shigella dysenteriae type 4. biochemical identification according to the analytical profile index, molecular serotyping by restriction of the amplified o-antigen gene cluster (rfb-rflp), together with phylogenetic analysis of the 16s rrna gene and multi-locus sequence analysis, identified the isolate as escheric ...201323748967
differential response of the cynomolgus macaque gut microbiota to shigella infection.little is known about the role of gut microbiota in response to live oral vaccines against enteric pathogens. we examined the effect of immunization with an oral live-attenuated shigella dysenteriae 1 vaccine and challenge with wild-type s. dysenteriae 1 on the fecal microbiota of cynomolgus macaques using 16 s rrna analysis of fecal samples. multi-dimensional cluster analysis identified different bacterial community types within macaques from geographically distinct locations. the fecal microbi ...201323755118
anti-platelet-activating factor, antibacterial, and antiradical activities of lipids extract from silver carp brain.epidemiological studies have verified the protective role of fish lipids in cardiovascular diseases. however, the effects of fish lipids on health boost remain undefined. large amounts of by-products, such as fish brain which contains high level of lipids, are produced with silver carp processing. fish brain is rich in bioactive lipids which are overwhelmingly effective in preventing cardiovascular diseases. the aim of this study was to elucidate the pharmacological activities of silver carp bra ...201323805935
in vitro selection of a dna aptamer targeted against shigella dysenteriae.to identify dna aptamers demonstrating binding specificity for shigella dysenteriae, a whole-bacterium systemic evolution of ligands by exponential enrichment (selex) method was applied to a combinatorial library of single-stranded dna (ssdna) molecules. after several rounds of selection using s. dysenteriae as the target, the highly enriched oligonucleotide pool was sequenced and then grouped into different families based on primary sequence homologies and similarities in the secondary structur ...201323811206
immunogenicity of a new recombinant ipac from shigella dysenteriae type i in guinea pig as a vaccine candidate.recombinant vaccine technology is one of the most developed means in controlling infectious diseases. however, an effective vaccine against shigella is still missing.201323811550
[urinary infection by shigella dysenteriae]. 201323817659
mistletoe lectin has a shiga toxin-like structure and should be combined with other toll-like receptor ligands in cancer therapy.mistletoe extract (me) is applied as an adjuvant treatment in cancer therapy in thousands of patients each year in europe. the main immunostimulating component of mistletoe extract, mistletoe lectin, recently has been shown to be a pattern recognition receptor ligand and hence is binding to an important class of pathogen-sensing receptors. pattern recognition receptor ligands are potent activators of dendritic cells. this activation is a prerequisite for a full-blown t-cell response against canc ...201323832140
antibacterial activity of actinomycetes isolated from different soil samples of sheopur (a city of central india).the main objective of the present study was isolation, purification, and characterization of actinomycetes from soil samples, having antimicrobial activity against 12 selected pathogenic strains. soils samples were taken from different niche habitats of sheopur district, madhya pradesh, india. these samples were serially diluted and plated on actinomycete isolation agar media. potential colonies were screened, purified, and stored in glycerol stock. isolates were morphologically and biochemicall ...201323833752
shigella takes the temperature.for bacteria, temperature is a fairly reliable cue for entry into a vertebrate host. many pathogenic bacteria sense elevated temperatures (37°c) and turn on virulence and metabolic genes appropriate for survival and growth within the host. a recent study demonstrated that the expression of a heme uptake protein in shigella dysenteriae and pathogenic escherichia coli was dependent on an rna thermometer.201523851363
prevention and inhibition of tc-1 cell growth in tumor bearing mice by hpv16 e7 protein in fusion with shiga toxin b-subunit from shigella dysenteriae.for immunotherapy of human papillomavirus (hpv) -16-associated cervical cancers the e7 protein is considered a prime candidate. however it is a poor inducer of cytotoxic t-cell response, when being used as a singular antigen in protein vaccination. hence, in this study we focused on the utilization of a vaccine delivery system for prevention or treatment of cervical cancer.201323862120
failure of manganese to protect from shiga toxin.shiga toxin (stx), the main virulence factor of shiga toxin producing escherichia coli, is a major public health threat, causing hemorrhagic colitis and hemolytic uremic syndrome. currently, there are no approved therapeutics for these infections; however manganese has been reported to provide protection from the stx1 variant isolated from shigella dysenteriae (stx1-s) both in vitro and in vivo. we investigated the efficacy of manganese protection from stx1-s and the more potent stx2a isoform, u ...201323875002
whole genome sequencing of an unusual serotype of shiga toxin-producing escherichia coli.shiga toxin-producing escherichia coli serotype o117:k1:h7 is a cause of persistent diarrhea in travelers to tropical locations. whole genome sequencing identified genetic mechanisms involved in the pathoadaptive phenotype. sequencing also identified toxin and putative adherence genes flanked by sequences indicating horizontal gene transfer from shigella dysenteriae and salmonella spp., respectively.201323877005
oxalis corniculata (oxalidaceae) leaf extract exerts in vitro antimicrobial and in vivo anticolonizing activities against shigella dysenteriae 1 (nt4907) and shigella flexneri 2a (2457t) in induced diarrhea in suckling mice.in this study, the extract of a green leafy vegetable oxalis corniculata (oxalidaceae) was evaluated for its in vitro antibacterial and in vivo anti colonizing effect against common intestinal pathogenic bacteria. methanolic extract (80%) of oxalis corniculata (oxalidaceae) leaf contained a polyphenol content of 910 mg gallic acid equivalent per gram of dry weight and the yield was 8%. the flavonoid content was 2.353 g quercetin equivalent per 100 g of the extract. in vitro studies indicated tha ...201323909903
haemolytic uraemic syndrome associated with pseudomonas aeruginosa sepsis.haemolytic uraemic syndrome (hus) is a recognized complication of infection with shiga toxin-producing escherichia coli (stec) and shigella dysenteriae type 1. infections with other micro-organisms, especially streptococcus pneumoniae, have been cited as causes of hus. in addition, influenza virus and other viruses may rarely be associated with this syndrome. a 2-year-old girl presented with severe pseudomonas aeruginosa sepsis with renal failure and ecthyma gangrenosum. further investigations r ...201323924661
the anti-shigellosis activity of the methanol extract of picralima nitida on shigella dysenteriae type i induced diarrhoea in rats.picralima nitida stapf (apocynaceae) is a medicinal plant used traditionally in cameroon to cure various ailments such as gastrointestinal disorders and dysentery. this study reports the in vitro and in vivo anti-shigellosis activity of the methanol extract of this plant on rats.201323957940
antioxidative, antimicrobial and cytotoxic effects of the phenolics of leea indica leaf extract.this study investigated the phytochemical, antioxidative, antimicrobial and cytotoxic effects of leea indica leaf ethanol extract. phytochemical values namely total phenolic and flavonoid contents, total antioxidant capacity, dpph radical scavenging effect, fecl3 reducing power, dmso superoxide scavenging effect and iron chelating effects were studied by established methods. antibacterial, antifungal and cytotoxic effects were screened by disk diffusion technique, food poison technique and brine ...201323961238
[studies on the mode of action of bacterial ab5 toxins].bacterial ab5 toxins are proteins, produced by pathogenic bacteria including of vibrio cholerae, shigella dysenteriae, and enterohaemorrhagic escherichia coli, which are usually released into the extracellular medium and cause disease by killing or altering the metabolism of target eukaryotic cells. the toxins are usually composed of one a subunit (a toxic domain) and five b subunits (a receptor-binding domain). this article overviews the characteristics and mode of actions of ab5 toxins includi ...201323985936
antioxidant and antimicrobial properties of phenolic rich fraction of seabuckthorn (hippophae rhamnoides l.) leaves in vitro.phenolic rich fraction (prf) from seabuckthorn leaves was prepared by sequential fractionation. total phenolic content of prf estimated as gallic acid equivalent was found to be 319.33±7.02 mg/g of prf. its major constituents gallic acid, rutin, quercetin-3-galactoside, quercetin-3-glucoside, myricetin, quercetin, kaempferol and isorhamnetin, were found in the range of 1.551-196.89 mg/g of prf as determined by rp-hplc. antioxidant activity of prf evaluated using 2,2-diphenyl-2-picrylhydrazyl, su ...201323993505
evaluation of an intragastric challenge model for shigella dysenteriae 1 in rhesus monkeys (macaca mulatta) for the pre-clinical assessment of shigella vaccine formulations.shigellosis is a worldwide disease, characterized by abdominal pain, fever, vomiting, and the passage of blood- and mucus-streaked stools. rhesus monkeys and other primates are the only animals that are naturally susceptible to shigellosis. a suitable animal model is required for the pre-clinical evaluation of vaccines candidates. in this study, the minimal dose of shigella dysenteriae1 1617 strain required to produce dysentery in four of five (80% attack rate) monkeys using an escalating dose r ...201424028276
protective immunity by oral immunization with heat-killed shigella strains in a guinea pig colitis model.the protective efficacy of and immune response to heat-killed cells of monovalent and hexavalent mixtures of six serogroups/serotypes of shigella strains (shigella dysenteriae 1, shigella flexneri 2a, s. flexneri 3a, s. flexneri 6, shigella boydii 4, and shigella sonnei) were examined in a guinea pig colitis model. a monovalent or hexavalent mixture containing 1 × 10(7) of each serogroup/serotype of heat-killed shigella cells was administered orally on days 0, 7, 14 and 21. on day 28, the immuni ...201324033533
synthesis of some novel bis[1, 2, 4]triazolo[3, 4-b][1, 3, 4]thiadiazine derivatives for antimicrobial evaluation.a new series of novel bis[1, 2, 4]triazolo[3, 4-b][1, 3, 4]thiadiazines 7a-j has been synthesized by the reaction of [5, 5'-methylenebis(3-methylbenzofuran-7, 5-diyl)]bis[(4-amino-5-thioxo-4, 5-dihydro-1h-1, 2, 4-triazol-3-yl)methanone] (6) with a variety of phenacyl bromides in ethanol under reflux for 6 h. all the newly synthesized compounds were tested for in vitro activity against certain strains of bacteria such as escherichia coli, klebsiella pneumoniae, shigella dysenteriae and shigella f ...201124062120
bacteriology of a most popular street food (panipuri) and inhibitory effect of essential oils on bacterial growth.bacteriology of panipuri was studied and the antibacterial effect of eight essential oils (eos) was established on pathogens found in panipuri. samples were collected from twelve respective vendors from different locations in baripada city, orissa. samples were fractionated into two parts viz. khatta pani and smashed potato masala used in panipuri. total plate count and isolation of pathogenic bacteria were done on both basal and selective media. coliforms were detected primarily by presumptive ...201224082267
antibacterial and antiviral evaluation of sulfonoquinovosyldiacylglyceride: a glycolipid isolated from azadirachta indica leaves.assessment of antibacterial as well as antiherpes virus activity of sulfonoquinovosyldiacylglyceride (sqdg), a glycolipid, isolated from the leaves of azadirachta indica has been described. antimicrobial activity was evaluated against gram-positive, gram-negative bacteria and herpes simplex virus. sqdg showed significant inhibitory activity against salmonella typhi and two isolates of shigella dysenteriae with mic values 32 μg ml(-1) , while three isolates of salm. typhi, escherichia coli and vi ...201424118020
mait cells detect and efficiently lyse bacterially-infected epithelial cells.mucosal associated invariant t cells (mait) are innate t lymphocytes that detect a large variety of bacteria and yeasts. this recognition depends on the detection of microbial compounds presented by the evolutionarily conserved major-histocompatibility-complex (mhc) class i molecule, mr1. here we show that mait cells display cytotoxic activity towards mr1 overexpressing non-hematopoietic cells cocultured with bacteria. the nk receptor, cd161, highly expressed by mait cells, modulated the cytokin ...201324130485
customizable pcr-microplate array for differential identification of multiple pathogens.customizable pcr-microplate arrays were developed for the rapid identification of salmonella typhimurium, salmonella saintpaul, salmonella typhi, shigella dysenteriae, escherichia coli o157:h7, francisella tularensis subsp. tularensis, francisella tularensis subsp. novicida, vibrio cholerae, vibrio parahaemolyticus, yersinia pestis, and yersinia pseudotuberculosis. previously, we identified highly specific primers targeting each of these pathogens. here, we report the development of customizable ...201324215700
isolation and molecular characterization of salmonella enterica, escherichia coli o157:h7 and shigella spp. from meat and dairy products in egypt.foodborne pathogens are a major threat to food safety, especially in developing countries where hygiene and sanitation facilities are often poor. salmonella enterica, escherichia coli o157:h7 and shigella spp. are among the major causes of outbreaks of foodborne diseases. this large-scale study investigated the prevalence of these foodborne pathogens in meat (beef and chicken) and dairy products collected from street vendors, butchers, retail markets and slaughterhouses in egypt. a total of 1600 ...201424239976
[microbial antagonism in the therapy of infectious diseases].the history of antibiotics begins with the first observations of pasteur and joubert about microbial antagonism at the end of the xix century. three types of antagonism were studied: bacterial killing by other bacteria, virus against bacteria and blockade of cellular receptors by bacterial filtrates. in the first type, the piocianase from pseudomonas aeruginosa and the activity of bacillus subtilis over mycobacterium tuberculosis were the better examples; in the second, the french d'herelle was ...201324248116
antibacterial activity of resin rich plant extracts.the in vitro antibacterial activity of resin rich methanolic extracts (rrmes) of commiphora myrrha, operculina turpethum, and pinus roxburghii.201324302834
shiga toxins expressed by human pathogenic bacteria induce immune responses in host cells.shiga toxins are a family of genetically and structurally related toxins that are the primary virulence factors produced by the bacterial pathogens shigella dysenteriae serotype 1 and certain escherichia coli strains. the toxins are multifunctional proteins inducing protein biosynthesis inhibition, ribotoxic and er stress responses, apoptosis, autophagy, and inflammatory cytokine and chemokine production. the regulated induction of inflammatory responses is key to minimizing damage upon injury o ...201324385347
promotion of quality standard of herbal medicine by constituent removing and adding.to identify major active constituents and measure their levels in a typical medicinal herb-rhizoma coptidis, we applied the concept of removing and adding, taking inspiration from functional genetic methods. as this herb has bacteriostatic properties and is used to treat bacterial diarrhea, we examined the effects of individual constituents (berberine, palmatine, coptisine, epiberberine, jateorrhizine and columbamine) on the growth of shigella dysenteriae with microcalorimetry. the removing and ...201424413194
regulation of cell-wall morphology and growth encoded by plasmids in shigella dysenteriae type 1.shigella dysenteriae type 1, isolated locally, was found to contain six plasmids and these could be eliminated using sds. a 70-kb plasmid was necessary to maintain the normal cell-wall morphology. synthesis of nine major membrane proteins (90 to 40 kda) was severely impaired in all-plasmid cured strains. electron microscopy revealed a prominent separation between the outer and inner membranes of the cured strains, indicating that plasmid loss led to defects in the cell envelope. the growth rates ...199524414647
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