Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| a rho gtpase controls the rate of protein synthesis in the sea urchin egg. | fertilization of the sea urchin egg triggers a ca(2+)-dependent cortical granule exocytosis and cytoskeletal reorganization, both of which are accompanied by an accelerated protein synthesis. the signaling mechanisms leading to these events are not completely understood. the possible role of rho gtpases in sea urchin egg activation was studied using the clostridium botulinum c3 exotoxin, which specifically adp-ribosylates rho proteins and inactivates them. we observed that incubation of eggs wit ... | 2003 | 14550256 |
| prevention and treatment of bacterial diseases caused by bacterial bioterrorism threat agents. | there is general consensus that the bacterial agents or products most likely to be used as weapons of mass destruction are bacillus anthracis, yersinia pestis, francisella tularensis and the neurotoxin of clostridium botulinum. modern supportive and antimicrobial therapy for inhalational anthrax is associated with a 45% mortality rate, reinforcing the need for better adjunctive therapy and prevention strategies. pneumonic plague is highly contagious, difficult to recognize and is frequently fata ... | 2003 | 14554016 |
| mechanism of c2-toxin inhibition by fluphenazine and related compounds: investigation of their binding kinetics to the c2ii-channel using the current noise analysis. | the binding component c2ii of the binary actin adp-ribosylating c2-toxin from clostridium botulinum is essential for intoxication of target cells. activation by a protease leads to channel formation and this is presumably required for the transport of the toxic c2i component into cells. the c2ii-channel is cation selective and contains a binding site for fluphenazine and structurally related compounds. ion transport through c2ii and in vivo intoxication is blocked when the sites are occupied by ... | 2003 | 14556742 |
| complete dna sequences of the botulinum neurotoxin complex of clostridium botulinum type a-hall (allergan) strain. | botox is manufactured with the purified native 900-kda type a neurotoxin complex from clostridium botulinum type a-hall (allergan) strain. this complex is composed of the botulinum neurotoxin (bont) and several toxin associated proteins known as the hemagglutinins (has) and the non-toxic non-hemagglutinin protein (ntnh). we describe here the complete gene sequences of the bont complex of type a-hall (allergan) strain. using a polymerase chain reaction-based approach, we sequenced six open readin ... | 2003 | 14557061 |
| involvement of cdc42 signaling in apoa-i-induced cholesterol efflux. | cholesterol efflux, an important mechanism by which high density lipoproteins (hdl) protect against atherosclerosis, is initiated by docking of apolipoprotein a-i (apoa-i), a major hdl protein, to specific binding sites followed by activation of atp-binding cassette transporter a1 (abca1) and translocation of cholesterol from intracellular compartments to the exofacial monolayer of the plasma membrane where it is accessible to hdl. in this report, we investigated potential signal transduction pa ... | 2003 | 14563854 |
| botulism type b presenting as pure autonomic dysfunction. | botulism nowadays is a rare mostly food-borne disease caused by the toxin of clostridium botulinum. on the other hand, botulinum toxin blocking cholinergic transmission has become a most powerful treatment option for many focal movement disorders and is increasingly used to treat autonomic disorders [2, 7, 8]. although muscle weakness is the hallmark of botulism, autonomic dysfunction may be the leading clinical symptom in rare cases and should be included in the differential diagnosis of pure d ... | 2003 | 14564656 |
| bactericidal effects of konjac fluid on several food-poisoning bacteria. | in this study, the bactericidal effects of japanese alkaline foods on food-poisoning bacteria were evaluated. konjac is an alkaline food soaked in calcinated calcium (the ph of konjac fluid ranges from 11.42 to 12.53). konjac fluids completely inactivated escherichia coli, enterohemorrhagic e. coli o157:h7 and e. coil o26:h9, salmonella enteritidis, vibrio parahemolyticus. and staphylococcus aureus. the initial level of 6 log cfu/ml dramatically decreased after incubation with konjac fluid, and ... | 2003 | 14572219 |
| hypoxia upregulates von hippel-lindau tumor-suppressor protein through rhoa-dependent activity in renal cell carcinoma. | a key task for the multifunctional von hippel-lindau protein (pvhl) is regulation of the activity of hypoxia-inducible factor-1alpha (hif-1alpha) by targeting it to the proteasome for degradation under normoxia. pvhl binding to hif-1alpha is lost under low o2 tension, leading to transcription of several genes involved in the hypoxia response. however, regulation of pvhl by hypoxia remains to be investigated. we evaluated the effects of hypoxia on pvhl expression in carcinoma and endothelial cell ... | 2004 | 14583436 |
| organization and regulation of the neurotoxin genes in clostridium botulinum and clostridium tetani. | botulinum and tetanus neurotoxins are structurally and functionally related 150 kda proteins that are potent inhibitors of neuroexocytosis. botulinum neurotoxin associates with non-toxic proteins to form complexes of various sizes. the botulinum neurotoxin and non-toxic protein genes are clustered in a dna segment called the botulinum locus. this locus is probably located on a mobile or degenerate mobile element, which accounts for the various genomic localizations (chromosome, plasmid, phage) i ... | 2004 | 16701505 |
| the actin-adp-ribosylating clostridium botulinum c2 toxin. | clostridium botulinum c2 toxin is the prototype of actin-adp-ribosylating toxins. the toxin consists of the enzyme component c2i and the separated binding/translocation component c2ii. c2ii is proteolytically activated to form heptamers, which bind the enzyme component. after endocytosis of the receptor-toxin complex, the enzyme component enters the cytosol from an acidic endosomal compartment to modify g-actin at arginine177. recent data indicate that chaperons are involved in the translocation ... | 2004 | 16701506 |
| regulation of neurotoxin complex expression in clostridium botulinum strains 62a, hall a-hyper, and nctc 2916. | the kinetics of botulinum toxin gene expression have been investigated in clostridium botulinum type a strains 62a, hall a-hyper, and type a(b) strain nctc 2916 during the growth cycle. the analyses were performed in tpgy and type a toxin production media (tpm). the mrna transcript levels encoding the proteins of the neurotoxin complex were determined using northern analyses. neurotoxin concentrations in culture supernatants and lysed cell pellets were assayed using elisa, western blots, and mou ... | 2004 | 16701534 |
| food-borne botulism. | 2004 | 15847370 | |
| clostridium perfringens alpha-toxin activates the sphingomyelin metabolism system in sheep erythrocytes. | clostridium perfringens alpha-toxin induces hemolysis of rabbit erythrocytes through the activation of glycerophospholipid metabolism. sheep erythrocytes contain large amounts of sphingomyelin (sm) but not phosphatidylcholine. we investigated the relationship between the toxin-induced hemolysis and sm metabolic system in sheep erythrocytes. alpha-toxin simultaneously induced hemolysis and a reduction in the levels of sm and formation of ceramide and sphingosine 1-phosphate (s1p). n-oleoylethanol ... | 2004 | 14702348 |
| subcutaneous administration of botulinum toxin a reduces formalin-induced pain. | botulinum toxin type a (bont-a) produced by the bacterium clostridium botulinum is a potent inhibitor of acetylcholine release in the neuromuscular junction and has been used to treat many disorders related to excessive muscle contraction. however, bont-a has recently been used in pain therapy to treat myofascial pain, low back pain and various types of headaches, including migraine. the purpose of this study is to investigate the antinociceptive effect of bont-a and its underlying mechanism in ... | 2004 | 14715398 |
| osteosynthesis-associated bone infection caused by a nonproteolytic, nontoxigenic clostridium botulinum-like strain. | a nonproteolytic, nontoxigenic clostridium botulinum strain identified by conventional and molecular techniques as type b-, e-, or f-like (bef-like) was isolated from a human postsurgical wound. all previous reports of such strains have been from environmental sources. since toxin production is the main taxonomic denominator for c. botulinum, a new name is needed for nonproteolytic, nontoxigenic bef-like clinical isolates. | 2004 | 14715812 |
| antibacterial efficiency of finnish spice essential oils against pathogenic and spoilage bacteria. | the antibacterial properties of 13 essential oils, derived from spices grown in finland, were examined with an agar diffusion method against 12 bacterial strains. the organisms tested included both spoilage and pathogenic bacteria. the gram-positive bacteria appeared to be more sensitive than the gram-negative organisms, clostridium botulinum and clostridium perfringens being the most sensitive. oregano, savory, and thyme showed the broadest antibacterial activity by distinctly inhibiting the gr ... | 2004 | 14717375 |
| mechanisms of internalization and recycling of the chemokine receptor, ccr5. | ccr5 is a g protein-coupled receptor that binds several natural chemokines but it is also a coreceptor for the entry of m tropic strains of hiv-1 into cells. levels of ccr5 on the cell surface are important for the rate of hiv-1 infection and are determined by a number of factors including the rates of ccr5 internalization and recycling. here we investigated the involvement of the actin cytoskeleton in the control of ligand-induced internalization and recycling of ccr5. cytochalasin d, an actin ... | 2004 | 14717692 |
| effects of injection of botulinum toxin type b into the external anal sphincter on anal pressure of horses. | to determine effects on anal pressure of horses after local injection of the external anal sphincter with clostridium botulinum toxin type b. | 2004 | 14719698 |
| a rho exchange factor mediates fmet-leu-phe-induced nf-kappab activation in human peripheral blood monocytes. | we reported previously that fmlp stimulates nf-kappab activation, and this function of fmlp requires small gtpase rhoa in human peripheral blood monocytes (huang, s., chen, l.-y., zuraw, b. l., ye, r. d., and pan, z. k. (2001) j. biol. chem. 276, 40977-40981). here we present evidence that rhoa associates specifically with the guanine nucleotide exchange factor lbc in human peripheral blood monocytes stimulated with fmlp and that lbc specifically catalyzes the guanine nucleotide exchange activit ... | 2004 | 14660653 |
| the apolipoprotein(a) component of lipoprotein(a) stimulates actin stress fiber formation and loss of cell-cell contact in cultured endothelial cells. | elevated plasma concentrations of lipoprotein(a) (lp(a)) are a risk factor for a variety of atherosclerotic disorders including coronary heart disease. in the current study, we report that incubation of cultured human umbilical vein or coronary artery endothelial cells with lp(a) elicits a dramatic rearrangement of the actin cytoskeleton characterized by increased central stress fiber formation and redistribution of focal adhesions. these effects are mediated by the apolipoprotein(a) (apo(a)) co ... | 2004 | 14660654 |
| the small gtp-binding protein rhoa regulates serotonin-induced na+-current response in the neurons of aplysia. | application of serotonin (5-ht) induces a slow inward current response in identified neurons of aplysia ganglia under voltage clamp. the 5-ht-induced current response was depressed in na+-free media, but augmented in ca2+-free media, and unaffected by a change in external k+. the 5-ht-induced response was markedly blocked by intracellular injection of guanosine 5'-o-(2-thiodiphosphate) (gdpbetas). after the injection of guanosine 5'-o-(3-thiotriphosphate) (gtpgammas), the responses to 5-ht gradu ... | 2004 | 14687879 |
| how adhesion, migration, and cytoplasmic calcium transients influence interleukin-1beta mrna stabilization in human monocytes. | we investigated the mechanisms by which primary human monocyte migration and the production of important cytokines are co-regulated. motile monocytes underwent cyclic morphologic and adhesive changes that were associated with intracellular free calcium changes; in such cells, cytokine transcripts were unstable and translationally repressed. agents that activate monocytes, including lipopolysacharrides (lps), cytomegalovirus (cmv), and tumor necrosis factor (tnfalpha), have been shown to de-repre ... | 2004 | 14743348 |
| identification of the major steps in botulinum toxin action. | botulinum toxin is a uniquely potent substance synthesized by the organisms clostridium botulinum, clostridium baratii, and clostridium butyricum. this toxin, which acts preferentially on peripheral cholinergic nerve endings to block acetylcholine release, is both an agent that causes disease (i.e., botulism) as well as an agent that can be used to treat disease (e.g., dystonia). the ability of botulinum toxin to produce its effects is largely dependent on its ability to penetrate cellular and i ... | 2004 | 14744243 |
| [infant botulism and sudden infant death syndrome]. | infant botulism represents a distinct entity of botulism. ingestion of the ubiquitously present spores of clostridium botulinum leads to germination of the organism and neurotoxin production in the infant intestine. symptoms typically develop gradually in contrast to classical food botulism in which an acute onset of symptoms shortly after the ingestion of preformed toxin in a food is characteristic. microbiologically, the diagnosis is established by identification of clostridium botulinum organ ... | 2004 | 14747968 |
| [sudden death of twins: botulism because of contamination by pap vegetables]. | botulism is caused by the blockage of the neural transmission in the cholinergic synapses by botulinum neurotoxin (bont) which is produced by clostridium botulinum or other clostridia. the classic form of botulism occurs after the ingestion of food contaminated by bont. the course of the infection can be asymptomatic, mild with subtle paralysis ("failure to thrive") oder severe with generalized paralysis ("floppy infant"). infected infants can also die sudden and unexpectedly. these deaths often ... | 2004 | 14747969 |
| cloning, high-level expression, single-step purification, and binding activity of his6-tagged recombinant type b botulinum neurotoxin heavy chain transmembrane and binding domain. | botulinum neurotoxins (bonts) are highly potent toxins that inhibit neurotransmitter release from peripheral cholinergic synapses and associate with infant botulism. bont is a approximately 150kda protein, consisting of a binding/translocating heavy chain (hc; 100kda) and a toxifying light chain (lc; 50kda) linked through a disulfide bond. c-terminal half of the heavy chain is binding domain, and n-terminal half of the heavy chain is translocation domain that includes transmembrane domain. a fun ... | 2004 | 14766296 |
| cloning, high level expression, purification, and crystallization of the full length clostridium botulinum neurotoxin type e light chain. | the catalytic activity of the highly potent botulinum neurotoxins are confined to their n-terminal light chains ( approximately 50kda). a full-length light chain for the type e neurotoxin with a c-terminal 6x his-tag, bont/e-lc, has been cloned in a pet-9c vector and over-expressed in bl21 (de3) cells. bont/e-lc was purified to homogeneity by affinity chromatography on ni-nta agarose followed by exclusion chromatography using a superdex-75 sizing column. the purified protein has very good solubi ... | 2004 | 14766304 |
| glycosphingolipids-sweets for botulinum neurotoxin. | a number of viruses, bacteria, and bacterial toxins can only act on cells that express the appropriate glycosphingolipids (gsls) on the outer surface of their plasma membranes. an example of this dependency is provided by botulinum neurotoxin (bont) which is synthesized by clostridium botulinum and inhibits neurotransmission at the neuromuscular junction by catalyzing hydrolysis of a snare protein, thereby inducing a flaccid paralysis. haemagglutinin components of progenitor forms of bont mediat ... | 2004 | 15514477 |
| characterization of toxin complex produced by a unique strain of clostridium botulinum serotype d 4947. | a unique strain of clostridium botulinum, serotype d 4947 (d-4947), produces a considerable amount of a 650 kda toxin complex (l-tc) and a small amount of a 280 kda m-tc, a 540 kda tc, and a 610 kda tc. the complexes are composed of only un-nicked components, including neurotoxin (nt), nontoxic nonhemagglutinin (ntnha) and hemagglutinin subcomponents (ha-70, ha-33 and ha-17). unlike other nts from all serotype strains, separation of d-4947 nt from l-tc, except for m-tc, during chromatography req ... | 2004 | 15517984 |
| modeling of seb-induced host gene expression to correlate in vitro to in vivo responses. | detection of exposure to biological threat agents has relied on ever more sensitive methods for pathogen identification, but that usually requires pathogen proliferation to dangerous, near untreatable levels. recent events have demonstrated that assessing exposure to a biological threat agent well in advance of onset of illness or at various stages post-exposure is invaluable among the diagnostic options. there is an urgent need for better diagnostic tools that will be sensitive, rapid, and unam ... | 2004 | 15522586 |
| natural clostridium botulinum type c toxicosis in a group of cats. | clinical signs of botulism were observed in a group of eight cats, four of which died, after being fed pelican carrion. clostridium botulinum type c was isolated from one cat. the microorganism and its toxin were found in the pelican. this is apparently the first report of natural botulism in cats. | 2004 | 15528757 |
| cnf and dnt. | the actin cytoskeleton of mammalian cells is involved in many processes that affect the growth and colonization of bacteria, such as migration of immune cells, phagocytosis by macrophages, secretion of cytokines, maintenance of epithelial barrier functions and others. with respect to these functions, it is not surprising that many bacterial protein toxins, which are important virulence factors and causative agents of human and/or animal diseases, target the actin cytoskeleton of the host. some t ... | 2004 | 15549605 |
| comparison of pressure and heat resistance of clostridium botulinum and other endospores in mashed carrots. | inactivation of bacterial endospores in food requires a combination of pressure and moderate heat. endospore resistance of seven clostridium botulinum strains was compared with those of bacillus spp. (b. cereus, b. subtilis, b. licheniformis, b. smithii, b. amyloliquefaciens) and thermoanaerobacterium thermosaccharolyticum with respect to pressure (600 to 800 mpa) and temperature (80 to 116 degrees c) treatments in mashed carrots. a large variation was observed in the pressure resistance of c. b ... | 2004 | 15553637 |
| n-cadherin juxtamembrane domain modulates voltage-gated ca2+ current via rhoa gtpase and rho-associated kinase. | the juxtamembrane domain (jmd) of n-cadherin cytoplasmic tail is an important regulatory region of the clustering and adhesion activities of the protein. in addition, the jmd binds a diversity of proteins capable of modifying intracellular processes including cytoskeletal rearrangement mediated by rho gtpases. these gtpases also function as regulators of voltage-activated calcium channels, which in turn modulate neuronal excitability. the present study was designed to determine whether there is ... | 2004 | 15574742 |
| differentiation of the gene clusters encoding botulinum neurotoxin type a complexes in clostridium botulinum type a, ab, and a(b) strains. | we describe a strategy to identify the clusters of genes encoding components of the botulinum toxin type a (bont/a) complexes in 57 strains of clostridium botulinum types a, ab, and a(b) isolated in italy and in the united states from different sources. specifically, we combined the results of pcr for detecting the ha33 and/or p47 genes with those of bont/a pcr-restriction fragment length polymorphism analysis. three different type a toxin gene clusters were revealed; type a1 was predominant amo ... | 2004 | 15574917 |
| the story of clostridium botulinum: from food poisoning to botox. | in the last fifty years, clostridium botulinum has become notorious for its ability to produce the deadly botulinum neurotoxins. while botulinum toxin a, better known as botox, is universally recognised by the public as a cosmetic enhancement tool, the botulinum neurotoxins are commonly used off-label for many medical conditions in ophthalmology, neurology and dermatology. the versatility of these botulinum toxins has made clostridium botulinum one of the most widely known bacterial pathogens in ... | 2004 | 15244362 |
| effects of mastic resin and its essential oil on the growth of proteolytic clostridium botulinum. | studies were done to determine the effect of mastic resin and its essential oil, alone and in conjunction with ethanol, on the growth of proteolytic strains of clostridium botulinum in media, and on neurotoxin production in challenge studies with english-style crumpets. preliminary studies, using a spot-on-the-lawn method, indicated that high levels of mastic resin in ethanol ( approximately 8% w/w) were required for complete inhibition of all strains of c. botulinum tested, but mastic resin in ... | 2004 | 15246242 |
| rho-mediated assembly of stress fibers is differentially regulated in corneal fibroblasts and myofibroblasts. | corneal keratocytes (stromal cells) are activated to fibroblasts and myofibroblasts during wound healing. myofibroblast transdifferentiation is accompanied by the expression of alpha-smooth muscle actin (alpha-sma) and the assembly of a robust stress fiber network and larger focal adhesions (fas). the regulation of the assembly of stress fibers was evaluated in cultured corneal fibroblast and myofibroblast phenotypes. in both cell types, the inhibition of rho gtpase activity by microinjecting c3 ... | 2004 | 15265703 |
| relationship between diffuse esophageal spasm and lower esophageal sphincter dysfunction on barium studies and manometry in 14 patients. | we sought to reassess the function and clinical characteristics of the lower esophageal sphincter in a series of patients with radiographically defined diffuse esophageal spasm. | 2004 | 15269034 |
| progress toward development of an inhalation vaccine against botulinum toxin. | the looming threat of bioterrorism has enhanced interest in the development of vaccines against agents such as botulinum toxin. this in turn has stimulated efforts to create vaccines that are effective by the oral and inhalation routes. recently, considerable progress has been made in creating an inhalation vaccine against botulism. this work stems from the discovery that a polypeptide that represents a third of the toxin molecule retains the ability to be adsorbed from the airway and to evoke a ... | 2004 | 15270652 |
| c3 exoenzyme from clostridium botulinum: structure of a tetragonal crystal form and a reassessment of nad-induced flexure. | c3 exoenzyme from clostridium botulinum (c3bot1) adp-ribosylates and thereby inactivates rho a, b and c gtpases in mammalian cells. the structure of a tetragonal crystal form has been determined by molecular replacement and refined to 1.89 a resolution. it is very similar to the apo structures determined previously from two different monoclinic crystal forms. an objective reassessment of available apo and nucleotide-bound c3bot1 structures indicates that, contrary to a previous report, the prote ... | 2004 | 15272191 |
| application of oligonucleotide array technology for the rapid detection of pathogenic bacteria of foodborne infections. | a rapid and accurate method for detection for common pathogenic bacteria in foodborne infections was established by using oligonucleotide array technology. nylon membrane was used as the array support. a mutation region of the 23s rrna gene was selected as the discrimination target from 14 species (genera) of bacteria causing foodborne infections and two unrelated bacterial species. a pair of universal primers was designed for pcr amplification of the 23s rrna gene. twenty-one species (genera)-s ... | 2004 | 15279944 |
| the c-terminus of botulinum neurotoxin type a light chain contributes to solubility, catalysis, and stability. | botulinum neurotoxin type a (bont/a) is the etiological agent responsible for botulism, a disease characterized by peripheral neuromuscular blockade. bont/a is produced by clostridium botulinum as a single chain protein that is activated by proteolytic cleavage to form a 50 kda light chain (lc, 448 amino acids) and a disulfide bond-linked 100 kda heavy chain (hc, 847 amino acids). whilst hc comprises the receptor binding and translocation domains, lc is a zn2+-endopeptidase that cleaves at a sin ... | 2004 | 15294297 |
| lysophospholipids increase icam-1 expression in huvec through a gi- and nf-kappab-dependent mechanism. | lysophosphatidic acid (lpa) and sphingosine 1-phosphate (s-1-p) are both low molecular weight lysophospholipid (lpl) ligands that are recognized by the edg family of g protein-coupled receptors. in endothelial cells, these two ligands activate edg receptors, resulting in cell proliferation and cell migration. the intercellular adhesion molecule-1 (icam-1, cd54) is one of many cell adhesion molecules belonging to the immunoglobulin superfamily. this study showed that lpa and s-1-p enhance icam-1 ... | 2004 | 15294853 |
| cell type-specific regulation of rhoa activity during cytokinesis. | rho family gtpases play pivotal roles in cytokinesis. by using probes based on the principle of fluorescence resonance energy transfer (fret), we have shown that in hela cells rhoa activity increases with the progression of cytokinesis. here we show that in rat1a cells rhoa activity remained suppressed during most of the cytokinesis. consistent with this observation, the expression of c3 toxin inhibited cytokinesis in hela cells but not in rat1a cells. furthermore, the expression of a dominant n ... | 2004 | 15308673 |
| clostridial neurotoxins. | 2004 | 15316043 | |
| association between key-gaskell syndrome and infection by clostridium botulinum type c/d. | there is growing evidence that equine dysautonomia is a toxicoinfection with clostridium botulinum type c. the possibility that feline dysautonomia has the same aetiology was investigated by attempting to detect botulinum type c neurotoxin in the food, faeces and the contents of the ileum of affected cats, and by serology. the toxin was detected directly in four of eight affected cats and after enrichment in seven of them, and in their dried food. no toxin was detected in healthy control cats or ... | 2004 | 15328740 |
| factors that contribute to the botulinal safety of reduced-fat and fat-free process chesse products. | the effects of fat, type of natural cheese, and adjunct process cheese ingredients were evaluated to determine factors that contribute to the botulinal safety of reduced-fat (rf) process cheese products stored at 30 degrees c. in the first set of experiments, pasteurized process cheese products (ppcps) were formulated using full-fat (ff) cheddar, 30% rf cheddar, or skim milk (sm) cheese as cheese-base types and were standardized to 59% moisture, ph 5.75, 2.8 or 3.2% total salts, and 15 to 19% fa ... | 2004 | 15330535 |
| antibotulinal activity of process cheese ingredients. | ingredients used in the manufacture of reduced-fat process cheese products were screened for their ability to inhibit growth of clostridium botulinum serotypes a and b in media. reinforced clostridial medium (rcm) supplemented with 0, 0.5, 1, 2, 3, 5, or 10% (wt/vol) of various ingredients, including a carbohydrate-based fat replacer, an enzyme-modified cheese (emc) derived from a blue cheese, sweet whey, modified whey protein, or whey protein concentrate, did not inhibit botulinal growth and to ... | 2004 | 15330547 |
| role of small gtp binding proteins in the growth-promoting and antiapoptotic actions of gastrin. | g17 has growth promoting and antiapoptotic effects on the ar4-2j pancreatic acinar cell line. we previously reported that whereas mapk regulates g17-stimulation of ar4-2j cell proliferation, akt mediates the antiapoptotic action of g17. we examined the signal-transduction pathways mediating g17 stimulation of ar4-2j cell growth and survival. g17 activated the small gtp binding proteins ras, rac, rho, and cdc42. transduction of the cells with adenoviral vectors expressing dominant negative akt, r ... | 2004 | 15331357 |
| phages and the evolution of bacterial pathogens: from genomic rearrangements to lysogenic conversion. | comparative genomics demonstrated that the chromosomes from bacteria and their viruses (bacteriophages) are coevolving. this process is most evident for bacterial pathogens where the majority contain prophages or phage remnants integrated into the bacterial dna. many prophages from bacterial pathogens encode virulence factors. two situations can be distinguished: vibrio cholerae, shiga toxin-producing escherichia coli, corynebacterium diphtheriae, and clostridium botulinum depend on a specific p ... | 2004 | 15353570 |
| efficacy of dna vaccines expressing the type f botulinum toxin hc fragment using different promoters. | dna vaccines which expressed the hc fragment of the clostridium botulinum type f neurotoxin (bont/f hc) fused to a signal peptide downstream of four different eukaryotic promoters were prepared. subsequently, the immunogenicity of the dna vaccines and protection afforded in mice against challenge with 10(4) mld of type f botulinum toxin was evaluated. the dna vaccine containing the human ubiquitin gene (ubc) promoter induced the highest bont/f hc-specific antibody concentration following two int ... | 2004 | 15364442 |
| prevalence of clostridium species and behaviour of clostridium botulinum in gnocchi, a repfed of italian origin. | sales and consumption of refrigerated processed foods of extended durability (repfeds) have increased many-fold in europe over the last 10 years. the safety and quality of these convenient ready-to-eat foods relies on a combination of mild heat treatment and refrigerated storage, sometimes in combination with other hurdles such as mild preservative factors. the major hazard to the microbiological safety of these foods is clostridium botulinum. this paper reports on the prevalence and behaviour o ... | 2004 | 15364467 |
| rho-modifying c3-like adp-ribosyltransferases. | c3-like exoenzymes comprise a family of seven bacterial adp-ribosyltransferases, which selectively modify rhoa, b, and c at asparagine-41. crystal structures of c3 exoenzymes are available, allowing novel insights into the structure-function relationships of these exoenzymes. because adp-ribosylation specifically inhibits the biological functions of the low-molecular mass gtpases, c3 exoenzymes are established pharmacological tools to study the cellular functions of rho gtpases. recent studies, ... | 2004 | 15372308 |
| role of metals in the biological activity of clostridium botulinum neurotoxins. | clostridium botulinum neurotoxins are the most potent toxins to humans and cause paralysis by blocking neurotransmitter release at the presynaptic nerve terminals. the toxicity involves four steps, viz., binding to neuronal cells, internalization, translocation, and catalytic activity. while the catalytic activity is a zinc endopeptidase activity on the snare complex proteins, the translocation is believed to be a ph-dependent process allowing the translocation domain to change its conformation ... | 2004 | 14979717 |
| characterization of six type a strains of clostridium botulinum that contain type b toxin gene sequences. | six clostridium botulinum isolates exhibiting type a toxicity as measured by the mouse bioassay were found to contain both type a and type b neurotoxin dna sequences. the six strains were divided into three groups based on the dna sequence of the type b neurotoxin gene. members of each group exhibited 100% sequence identity over the 3876 bp type b toxin open reading frame. the type b toxin sequence of all groups differed at more than 60 positions when compared to the bgb control strain. | 2004 | 14987759 |
| prevalence of clostridium botulinum in food raw materials used in repfeds manufactured in france. | food raw materials used in refrigerated processed foods of extended durability (repfeds) manufactured in france were surveyed for clostridium botulinum types a, b and e using pcr-enzyme-linked immunosorbent assay (pcr-elisa) and mouse bioassay for detection respectively of cells and toxins in enrichment broth. portions of 25 to 50 g of food were analysed. a total of 8 out of the 102 samples of fish and shellfish, 12 out of the 143 samples of meat and poultry, 1 out of the 62 samples of aroma, sa ... | 2004 | 14996457 |
| is fish consumption safe? | louisiana's vital seafood industry provides nearly 40% of domestic seafood production. unlike louisianans, most americans do not enjoy fresh seafood, yet manage to eat over 4 billion pounds of seafood annually, most of it foreign, frozen, and fried! america's commercial fisheries now face crippling economic and environmental pressures from seafood imports, over-fishing, urban and agricultural wastewater runoff, harmful algal blooms, and coastal wetlands loss. as a result of these ecosystem stres ... | 2004 | 15000214 |
| a rho-signaling pathway mediates cortical granule translocation in the sea urchin oocyte. | cortical granules are secretory vesicles of the egg that play a fundamental role in preventing polyspermy at fertilization. in the sea urchin egg, they localize directly beneath the plasma membrane forming a compact monolayer and, upon fertilization, undergo a ca(2+)-dependent exocytosis. cortical granules form during early oogenesis and, during maturation, translocate from the cytosol to the oocyte cortex in a microfilament-mediated process. we tested the hypothesis that these cortical granule ... | 2004 | 15003626 |
| matrix-specific activation of src and rho initiates capillary morphogenesis of endothelial cells. | interstitial collagen i stimulates microvascular endothelial cells to form solid cords that imitate precapillary structures found during angiogenesis. time-lapse microscopy identified cell retraction and disruption of cell-cell contacts as early critical steps in collagen i-induced capillary morphogenesis. these early stages paralleled collagen i activation of src kinase and gtpase rho through beta1 integrins. the src inhibitor pp2, dominant-negative src, and rho inhibitor exoenzyme c3 transfera ... | 2004 | 15003991 |
| regulation of osteoblast differentiation by pasteurella multocida toxin (pmt): a role for rho gtpase in bone formation. | the role of the rho-rho kinase signaling pathway on osteoblast differentiation was investigated using primary mouse calvarial cells. the bacterial toxin pmt inhibited, whereas rho-rok inhibitors stimulated, osteoblast differentiation and bone nodule formation. these effects correlated with altered bmp-2 and -4 expression. these data show the importance of rho-rok signaling in osteoblast differentiation and bone formation. | 2004 | 15005854 |
| botulin toxin: a weapon in terrorism. | clostridium botulinum, the causative agent of botulism is an anaerobic, spore forming gram-positive bacillus. c. botulinum causes three types of botulism; foodborne botulism, wound botulism, and infant botulism. most strains of the bacterium produce a potent, muscle-paralyzing neurotoxin. respiratory failure secondary to paralysis of the respiratory muscles can lead to death unless appropriate therapy is promptly initiated. due to the severity and potency of this neurotoxin, its importance as a ... | 2004 | 15011978 |
| mechanisms involved in new therapies for overactive bladder. | during the last few years, vanilloid substances and botulinum-a toxin were extensively investigated as new therapies for overactive bladder. intravesical administration of capsaicin or resiniferatoxin--2 members of the vanilloid family--has been shown to increase bladder capacity and decrease urge incontinence in patients with neurogenic, as well as nonneurogenic, forms of detrusor overactivity. in addition, vanilloids have been shown also to reduce bladder pain in patients with hypersensitive d ... | 2004 | 15013655 |
| historical notes on botulism, clostridium botulinum, botulinum toxin, and the idea of the therapeutic use of the toxin. | food-borne botulism probably has accompanied mankind since its beginning. however, we have only few historical sources and documents on food poisoning before the 19th century. some ancient dietary laws and taboos may reflect some knowledge about the life-threatening consumption of poisoned food. one example of such a dietary taboo is the 10th century edict of emperor leo vi of byzantium in which manufacturing of blood sausages was forbidden. some ancient case reports on intoxications with atropa ... | 2004 | 15027048 |
| retargeted clostridial endopeptidases: inhibition of nociceptive neurotransmitter release in vitro, and antinociceptive activity in in vivo models of pain. | clostridial neurotoxins potently and specifically inhibit neurotransmitter release in defined cell types. previously reported data have demonstrated that the catalytically active lh(n) endopeptidase fragment of botulinum neurotoxin type a (termed lh(n)/a) can be retargeted to a range of cell types in vitro to lead to inhibition of secretion of a range of transmitters. here, we report the synthesis of endopeptidase conjugates with in vitro selectivity for nociceptive afferents compared to spinal ... | 2004 | 15027053 |
| quantification of toxin-encoding mrna from clostridium botulinum type e in media containing sorbic acid or sodium nitrite by competitive rt-pcr. | competitive reverse transcription polymerase chain reaction (crt-pcr) was used to quantify the toxin-encoding mrna production of a clostridium botulinum type e strain in media containing either sorbic acid or sodium nitrite. a 10-fold reduction in toxin mrna production and a 25-fold reduction in the proportion of toxin mrna to total rna, was estimated when either 1 mg ml(-1) sorbic acid or 100 microg ml(-1) sodium nitrite were added to the medium at ph 7.0. | 2004 | 15033232 |
| a highly sensitive immuno-polymerase chain reaction assay for clostridium botulinum neurotoxin type a. | our goal was to develop a sensitive method for detecting clostridium botulinum neurotoxin type a (bont/a). we were able to detect bont/a in the femtogram (10(-15)g) range using an indirect immuno-polymerase chain reaction (immuno-pcr) assay and an indirect sandwich immuno-pcr assay. for the indirect immuno-pcr assay, enzyme-linked immunosorbent assay (elisa) plates were coated with bont/a that was recognized by anti-bont/a monoclonal antibody. for the indirect sandwich immuno-pcr assay, the mono ... | 2004 | 15037026 |
| an epidemiological study of risk factors associated with the recurrence of equine grass sickness (dysautonomia) on previously affected premises. | the reasons why equine grass sickness (egs) recurs on premises are unknown and, consequently, practical methods for reducing the risk of recurrence are not available. | 2004 | 15038431 |
| equine grass sickness is associated with low antibody levels to clostridium botulinum: a matched case-control study. | equine grass sickness is a high mortality disease which, despite many years of investigation, is of unknown aetiology. recent findings indicating that the disease is associated with clostridium botulinum require support from an epidemiological study that recognises and controls for potential confounders, e.g. age, time of year and premises. | 2004 | 15038434 |
| prospects for vaccination against equine grass sickness. | 2004 | 15038444 | |
| vaccines against biologic agents: uses and developments. | although the geneva protocol that prohibits the use of chemical and biologic weapons was ratified in 1925, many countries failed to accept this protocol: others stipulated retaliation, and some, like the united states, did not ratify the protocol for decades. this delay allowed the continued development of chemical and biologic agents. members of the health care community are responsible for determining the best way to protect society from the potentially devastating effects of these biologic ag ... | 2004 | 15062232 |
| dual toxin-producing strain of clostridium botulinum type bf isolated from a california patient with infant botulism. | a retrospective study of clostridium botulinum strains isolated from patients from california with infant botulism identified the fourth known c. botulinum strain that produces both type b and type f botulinum toxins. this unique strain represented 0.12% of the california infant botulism case isolates from 1976 to 2003. the relative concentrations of type b and f toxins produced were temperature dependent. | 2004 | 15071029 |
| shelf life and safety concerns of bakery products--a review. | bakery products are an important part of a balanced diet and, today, a wide variety of such products can be found on supermarket shelves. this includes unsweetened goods (bread, rolls, buns, crumpets, muffins and bagels), sweet goods (pancakes, doughnuts, waffles and cookies) and filled goods (fruit and meat pies, sausage rolls, pastries, sandwiches, cream cakes, pizza and quiche). however, bakery products, like many processed foods, are subject to physical, chemical and microbiological spoilage ... | 2004 | 15077880 |
| homology modeling and molecular dynamics studies of a novel c3-like adp-ribosyltransferase. | the novel c3-like adp-ribosyltransferase is produced by a staphylococcus aureus strain that especially adp-ribosylates rhoe/rnd3 subtype proteins, and its three-dimensional (3d) structure has not known. in order to understand the catalytic mechanism, the 3d structure of the protein is built by using homology modeling based on the known crystal structure of exoenzyme c3 from clostridium botulinum (1g24). then the model structure is further refined by energy minimization and molecular dynamics met ... | 2004 | 15080907 |
| enhancement of the endopeptidase activity of purified botulinum neurotoxins a and e by an isolated component of the native neurotoxin associated proteins. | in botulism disease, neurotransmitter release is blocked by a group of structurally related neurotoxin proteins produced by clostridium botulinum. botulinum neurotoxins (bont, a-g) enter nerve terminals and irreversibly inhibit exocytosis via their endopeptidase activities against synaptic proteins snap-25, vamp, and syntaxin. type a c. botulinum secretes the neurotoxin along with 5 other proteins called neurotoxin associated proteins (naps). here, we report that hemagglutinin-33 (hn-33), one of ... | 2004 | 15096048 |
| crystal structure of clostridium botulinum neurotoxin protease in a product-bound state: evidence for noncanonical zinc protease activity. | clostridium botulinum neurotoxins (bonts), the most potent toxins known, disrupt neurotransmission through proteolysis of proteins involved in neuroexocytosis. the light chains of bonts are unique zinc proteases that have stringent substrate specificity and require exceptionally long substrates. we have determined the crystal structure of the protease domain from bont serotype a (bont/a). the structure reveals a homodimer in a product-bound state, with loop f242-v257 from each monomer deeply bur ... | 2004 | 15107500 |
| control of expression of the lectin-like protein reg-1 by gastrin: role of the rho family gtpase rhoa and a c-rich promoter element. | the expression of members of the reg family of secreted lectin-like proteins is increased in response to stress, inflammation and damage in many tissues. in the stomach, reg is located in enterochromaffin-like cells, where its expression is stimulated by the gastric hormone gastrin. we have examined the mechanisms by which gastrin stimulates expression of reg-1. deletional mutations of 2.1 to 0.1 kb of the rat reg-1 promoter in a luciferase reporter vector were transiently transfected into gastr ... | 2004 | 15109306 |
| fatal type a botulism in south africa, 2002. | although wildfowl and domestic livestock botulism has been recognized as a problem in southern africa, very few human cases have ever been described in the region. in late february 2002, two siblings aged eight and 12 years developed acute flaccid paralysis and died. mouse bioassays revealed the presence of type a botulinum toxin in the serum of both children, and in the retrieved remains of the implicated food. the implicated vehicle of the toxin was tinned fish in tomato sauce, commercially pr ... | 2004 | 15109552 |
| mapping of the antibody-binding regions on the hn-domain (residues 449-859) of botulinum neurotoxin a with antitoxin antibodies from four host species. full profile of the continuous antigenic regions of the h-chain of botulinum neurotoxin a. | previously, we mapped the antibody (ab) and t-cell recognition regions on the hc domain (residues 855-1296) of the 848-residue heavy (h) chain of botulinum neurotoxin a (bont/a). we have mapped here the hn-domain (residues 449-859) regions that bind protective anti-bont/a abs raised in four different species. we synthesized, purified, and characterized 29 19-residue peptides that spanned the entire hn and overlapped consecutively by 5 residues, and also region l218-231 around the l-chain's subst ... | 2004 | 15115181 |
| characterisation of botulinum toxins type c, d, e, and f by matrix-assisted laser desorption ionisation and electrospray mass spectrometry. | in a follow-up of the earlier characterisation of botulinum toxins type a and b (btxa and btxb) by mass spectrometry (ms), types c, d, e, and f (btxc, btxd, btxe, btxf) were now investigated. botulinum toxins are extremely neurotoxic bacterial toxins, likely to be used as biological warfare agent. biologically active btxc, btxd, btxe, and btxf are comprised of a protein complex of the respective neurotoxins with non-toxic non-haemagglutinin (ntnh) and, sometimes, specific haemagglutinins (ha). t ... | 2004 | 15117079 |
| outbreak of necrotizing fasciitis due to clostridium sordellii among black-tar heroin users. | in california, black tar heroin (bth) use among injection drug users (idus) has resulted in an increased number of cases of wound botulism due to clostridium botulinum, tetanus due to clostridium tetani, and necrotizing soft-tissue infections due to a variety of clostridia. from december 1999 to april 2000, nine idus in ventura county, california, developed necrotizing fasciitis; 4 died. cultures of wound specimens from 6 case patients yielded clostridium sordellii. some of the patients appeared ... | 2004 | 15127359 |
| evaluation of a clostridium perfringens predictive model, developed under isothermal conditions in broth, to predict growth in ground beef during cooling. | proper temperature control is essential in minimizing clostridium perfringens germination, growth, and toxin production. the u.s. department of agriculture (usda) food safety and inspection service (fsis) offers two options for the cooling of meat products: follow a standard time-temperature schedule or validate that alternative cooling regimens result in no more than a 1-log(10) cfu/g increase of c. perfringens and no growth of clostridium botulinum. a mathematical model developed by juneja et ... | 2004 | 15128525 |
| relative neurotoxin gene expression in clostridium botulinum type b, determined using quantitative reverse transcription-pcr. | a quantitative reverse transcription-pcr (qrt-pcr) method was developed to monitor the relative expression of the type b botulinum neurotoxin (bont/b) gene (cntb) in clostridium botulinum. the levels of cntb mrna in five type b strains were accurately monitored by using primers specific for cntb and for the reference gene encoding the 16s rrna. the patterns and relative expression of cntb were different in the different strains. except for one of the strains investigated, an increase in cntb exp ... | 2004 | 15128552 |
| quantitative interaction effects of carbon dioxide, sodium chloride, and sodium nitrite on neurotoxin gene expression in nonproteolytic clostridium botulinum type b. | the effects of carbon dioxide, sodium chloride, and sodium nitrite on type b botulinum neurotoxin (bont/b) gene (cntb) expression in nonproteolytic clostridium botulinum were investigated in a tryptone-peptone-yeast extract (tpy) medium. various concentrations of these selected food preservatives were studied by using a complete factorial design in order to quantitatively study interaction effects, as well as main effects, on the following responses: lag phase duration (lpd), growth rate, relati ... | 2004 | 15128553 |
| molecular characterization of binding subcomponents of clostridium botulinum type c progenitor toxin for intestinal epithelial cells and erythrocytes. | clostridium botulinum type c 16s progenitor toxin consists of a neurotoxin (ntx), a non-toxic non-ha (ntnh), and a haemagglutinin (ha). the ha acts as an adhesin, allowing the 16s toxin to bind to intestinal epithelial cells and erythrocytes. in type c, these bindings are dependent on sialic acid. the ha consists of four distinct subcomponents designated ha1, ha2, ha3a and ha3b. to identify the binding subcomponent(s) of ha of type c 16s toxin, all of the ha-subcomponents and some of their precu ... | 2004 | 15133114 |
| vaccination with recombinant whole heavy chain fragments of clostridium botulinum type c and d neurotoxins. | mice and ducks were subcutaneously immunized with recombinant whole heavy (h) chains of clostridium botulinum type c and d neurotoxins, which were expressed as glutathione s-transferase fusion proteins. in the case of mice, it was confirmed that two immunizations with type c- and d-h chains, 10 microg each time, significantly increased the specific antibodies against 100-kda h chains of type c and d neurotoxins in an immunoblot analysis and an enzyme-linked immunosorbent assay, respectively. the ... | 2004 | 15138174 |
| botulinum toxin type a targets rhob to inhibit lysophosphatidic acid-stimulated actin reorganization and acetylcholine release in nerve growth factor-treated pc12 cells. | botulinum toxin type a (bont/a) produced by clostridium botulinum inhibits ca2+-dependent acetylcholine (ach) release (neuroexocytosis) at peripheral neuromuscular junctions, sometimes causing neuromuscular paralysis. this inhibitory effect is attributed to its metalloprotease activity to cleave the 25-kda synaptosomal-associated protein, which is essential for the exocytotic machinery. however, deletion of this protein does not result in a complete block of neuroexocytosis, suggesting that botu ... | 2004 | 15140914 |
| small tripeptide surrogates with low nanomolar affinity as potent inhibitors of the botulinum neurotoxin b metallo-proteolytic activity. | botulinum neurotoxin type b is a high-weight (150 kda) protein produced by the anaerobic bacillus clostridium botulinum. this metallo-protease neurotoxin cleaves synaptobrevin, a protein, which is crucial to neurotransmission, resulting in the muscle paralysis, which characterizes botulism. inhibition of the metallo-peptidase activity is a possible approach to obtain specific therapeutics to treat botulism. we have previously reported a successful attempt to block the proteolytic activity of thi ... | 2004 | 15142564 |
| clostridium botulinum c2 toxin--new insights into the cellular up-take of the actin-adp-ribosylating toxin. | clostridium botulinum c2 toxin is a member of the family of binary actin-adp-ribosylating toxins. it consists of the enzyme component c2i, and the separated binding/translocation component c2ii. proteolytically activated c2ii forms heptamers and binds to a carbohydrate cell surface receptor. after attachment of c2i, the toxin complex is endocytosed to reach early endosomes. at low ph of endosomes, c2ii-heptamers insert into the membrane, form pores and deliver c2i into the cytosol. here, c2i adp ... | 2004 | 15149031 |
| wound botulism in the uk and ireland. | there are three main, naturally occurring, epidemiological types of botulism: food-borne, intestinal colonization (infant botulism) and wound botulism. the neurological signs and symptoms are the same for all three epidemiological types and may include respiratory paralysis. wound botulism is caused by growth of cells and release of toxin in vivo, is associated with traumatic wounds and abscesses and has been reported in drug users, such as those injecting heroin or sniffing cocaine. up to the e ... | 2004 | 15150338 |
| characterization of bacillus cereus isolates from raw soybean sprouts. | raw soybean sprouts, which are used as ingredients in cook-chilled products, were analyzed to evaluate the incidence of mesophilic aerobic microorganisms, psychrotrophic microorganisms, anaerobic microorganisms, coliforms, and spore-forming microorganisms bacillus cereus, clostridium botulinum, and clostridium perfringens. mesophilic microorganisms on raw soybean sprouts were present in large populations, 5.5 x 10(6) to 1.4 x 10(8) cfu/g, and psychrotrophic microorganisms were found to be more n ... | 2004 | 15151246 |
| structural analysis of botulinum neurotoxin type e catalytic domain and its mutant glu212-->gln reveals the pivotal role of the glu212 carboxylate in the catalytic pathway. | the seven serotypes of botulinum neurotoxins (a-g) produced by clostridium botulinum share significant sequence homology and structural similarity. the functions of their individual domains and the modes of action are also similar. however, the substrate specificity and the peptide bond cleavage selectivity of their catalytic domains are different. the reason for this unique specificity of botulinum neurotoxins is still baffling. if an inhibitor leading to a therapeutic drug common to all seroty ... | 2004 | 15157097 |
| nucleotide sequence and transcriptional analysis of the type a2 neurotoxin gene cluster in clostridium botulinum. | the nucleotide sequences of the upstream regions of the botulinum neurotoxin type a1 (bont/a1) cluster of clostridium botulinum strain nctc 2916 and the bont/a2 cluster of strain kyoto-f were determined. a novel gene, designated orfx3, was identified following the orfx2 gene in both clusters. orf-x2 and orf-x3 exhibit similarity to the bont cluster associated p-47 protein. the bont/a1 and bont/a2 clusters share a similar gene arrangement, but exhibit differences in the spacing between certain ge ... | 2004 | 15158256 |
| mechanisms involved in carbachol-induced ca(2+) sensitization of contractile elements in rat proximal and distal colon. | 1. mechanisms involved in ca(2+) sensitization of contractile elements induced by the activation of muscarinic receptors in membrane-permeabilized preparations of the rat proximal and distal colon were studied. 2. in alpha-toxin-permeabilized preparations from the rat proximal and distal colon, ca(2+) induced a rapid phasic and subsequent tonic component. after ca(2+)-induced contraction reached a plateau, guanosine 5'-triphosphate (gtp) and carbachol (cch) in the presence of gtp further contrac ... | 2004 | 15159278 |
| clostridium botulinum and the clinical laboratorian: a detailed review of botulism, including biological warfare ramifications of botulinum toxin. | this review article is designed to thoroughly familiarize all health care professionals with the history, classification, epidemiology, clinical characteristics, differential diagnosis, diagnostic evaluation (including laboratory-based testing), treatment, and prognosis of botulism. it is especially targeted toward clinical laboratorians and includes a detailed enumeration of the important clinical laboratory contributions to the diagnosis, treatment, and monitoring of patients with botulism. fi ... | 2004 | 15163234 |
| management of pharyngoesophageal spasm with botox. | pharyngoesophageal spasm following laryngectomy can result in failure of tracheoesophageal (te) speech and dysphagia. chemical denervation with clostridium botulinum toxin (botox) is effective in relieving pharyngeal constrictor spasm, thereby facilitating te speech production. this article reviews the technique, results,and complications regarding the use of botox in the management of te speech failure associated with pharyngoesophageal spasm. | 2004 | 15163601 |
| a severe case of infant botulism caused by clostridium botulinum type a with concomitant intestinal viral infections. | 2004 | 15170567 | |
| functional role of rhoa in growth regulation of primary hepatocytes. | the expression, activation and involvement in growth regulation of a small gtpase, rhoa, were examined in rat primary hepatocyte cultures. hepatocytes freshly isolated from liver expressed rhoa protein at high levels. the total level of rhoa protein in the cells decreased markedly within a day in monolayer cultures. thereafter, rhoa expression recovered as cell-cell attachment occurred during the culture. on the other hand, the level of the active form of rhoa decreased as the culture proceeded. ... | 2004 | 15173202 |
| the receptor and transporter for internalization of clostridium botulinum type c progenitor toxin into ht-29 cells. | orally ingested botulinum toxin enters the circulatory system and eventually reaches the peripheral nerves, where it elicits a response of neurological dysfunction. in this study, we report the important findings concerning the mechanism of clostridium botulinum type c progenitor toxin (c16s) endocytic mechanism. c16s toxin bound to high molecular weight proteins on the surface of human colon carcinoma ht-29 cells and was internalized, but not if the cells were pretreated with neuraminidase. ben ... | 2004 | 15178410 |
| novel application of an in vitro technique to the detection and quantification of botulinum neurotoxin antibodies. | detection of clostridium botulinum neurotoxin (bont) neutralising antibodies is currently achieved using the mouse lethality assay (mla). this technique has provided the majority of the data for vaccine development and, with the increasing use of bont as a therapeutic agent, the mla is the assay of choice to evaluate 'non-responder' antisera. however, the mla is semi-quantitative and has an animal consumption rate that raises ethical concerns. the development of an alternative is therefore desir ... | 2004 | 15183085 |