bluuebunny/crossref_metadata_2025_split huggingface dataset:
Release of heptapeptide toxin (microcystin) during the decomposition process of Microcystis aeruginosa
Authors: Watanabe Mariyo F. , Tsuji Kiyomi , Watanabe Yasunori , Harada Ken‐Ichi , Suzuki Makoto 
Published: October 2006

AbstractThe decomposition process of toxic blue‐green alga (cyanobacteria), Microcystis aeruginosa, under dark and aerobic condition was investigated in relation to the change of the amounts of heptapeptide toxins (microcystins YR and LR) by two experiments: one with Microcystis cells and the other with two purified microcystins. In the experiment with Microcystis cells, an increase of heterotrophic bacteria observed from the beginning of the experiment, was followed by decomposition of the algal cells and the subsequent release of microcystins into the filtrate fraction. The amounts of the toxins initially present in the cells were quantitatively detected in the filtrate fraction on the 35th day. The decomposition of microcystin YR began on the 42nd day. The decomposition rate of the two toxins was different. The decomposition rate of purified microcystins YR and LR, compared in distilled water and culture medium, respectively, indicated clearly that microcystin YR was more labile to decomposition than microcystin LR in the culture medium. At the end of the experiment (45th day) microcystin YR decreased to 58.6%, while 86.2% of microcystin LR remained. © 1992 Wiley‐Liss, Inc.
Poisoning by Coprinus atramentarius
Authors: Michelot Didier 
Published: October 2006

AbstractThe ink cap—Coprinus atramentarius (Bulliard ex Fries) Fries—is responsible for poisoning when ingested with alcohol. The investigation of the “Coprinus syndrome,” although a minor poisoning incident, stimulated numerous research programs because the results were expected to yield a novel drug useful during the treatment of alcoholism. This work led to the identification of the active principle—coprine—and to an explanation of its mode of action; nevertheless, detailed toxicology investigations have shown that the mutagenic and gonadotoxic properties of this compound made it unsuitable for therapeutic use. Our current knowledge of the poisoning, the chemistry of the toxin, and its mode of action are here reviewed. © 1992 Wiley‐Liss, Inc.
Alkaloid toxins in endophyte‐infected grasses
Authors: Powell Richard G. , Petroski Richard J. 
Published: October 2006

AbstractGrasses infected with clavicipitaceous fungi have been associated with a variety of diseases including classical ergotism in humans and animals, fescue foot and summer syndrome in cattle, and ryegrass staggers in sheep. During the last decade it has been recognized that many of these fungal infections are endophytic; a fungal endophyte is a fungus that grows entirely within the host plant. Inspection of field collections and herbarium specimens has revealed that such infections are widespread in grasses. The chemistry associated with these grass‐fungal interactions has proved to be interesting and complex, as each grass‐fungal pair results in a unique “fingerprint” of various alkaloids, of which some are highly toxic to herbivores. In many cases the presence of an endophyte appears to benefit the plant by increasing drought resistance, or by increasing resistance to attack by insects, thus improving the overall survivability of the grass. This review will focus on alkaloids that have been reported in endophyte‐infected grasses. © 1992 Wiley‐Liss, Inc.
Ecology, metabolite production, and substrate utilization in endophytic fungi
Authors: Petrini Orlando , Sieber Thomas N. , Toti Luigi , Viret Olivier 
Published: October 2006

AbstractEndophytic fungi are a taxonomically and ecologically heterogenous group of organisms, mainly belonging to the Ascomycotina and Deuteromycotina. The isolation methods affect the species composition of the endophyte assemblage in a given host. The number of endophyte taxa isolated from a host species is usually large; however, only few, normally host specific species or strains are dominant. Endophyte assemblages are specific at the host species level, but species composition and frequencies are significantly affected by site‐specific conditions. Moreover, the relative importance and number of endophytic species vary among individuals within sites. In some cases, each individual could be considered a separate ecosystem. In general, however, 40 individuals with 30 to 40 sampling units per organ and individual should be enough to detect 80% of taxa present in a given host at one site. Endophytes usually produce the enzymes necessary for the colonization of plant tissues. Substrate utilization studies and isozyme analysis have demonstrated that most endophytes are able to utilize most plant cell components. The production of growth promoting factors and of metabolites useful in the pharmaceutical and agricultural industry is widespread among endophytic fungi. The usefulness of endophytes in agricultural and pharmaceutical research is briefly discussed. © 1992 Wiley‐Liss, Inc.
A preliminary investigation on renal and hepatic toxicity in rats fed purified fumonisin B1
Authors: Voss Kenneth A. , Chamberlain William J. , Bacon Charles W. , Norred William P. 
Published: October 2006

AbstractFumonisins are metabolites of Fusarium moniliforme and other Fusarium spp. Fumonisin B1 (FB1) was hepatocarcinogenic (50 ppm, ⩾ 90% purity) when fed to male rats; however, neither the effects of FB1 on females nor the relationship between dietary FB1 levels and toxicity in rats has been reported. Male and female rats (three per sex per group) were fed diets fortified with 0, 15, 50 or 150 ppm FB1 (⩾ 99% purity) for 4 weeks. There were no differences in general appearance or behavior among groups and significant differences in weight gain or food consumption were not found. Histopathological examinations and serum chemical profiles, including significant increases in triglycerides, cholesterol, and alkaline phosphatase, confirmed that 150 ppm FB1 was hepatotoxic to both sexes. Cortical nephrosis was found in males fed ⩾ 15 ppm and females fed ⩾ 50 ppm FB1. Both hepatic and renal lesions were consistent with those found in rats consuming F. moniliforme‐infected com. Thus, highly purified FB1 is unequivocally capable of inducing the subchronic liver and kidney lesions attributed to F. moniliforme. Published 1993 Wiley‐Liss, Inc.
A sensitive fluorogenic enzyme linked immunosorbent assay for the detection of Vipera russelli venom
Authors: Bhatti Abdul R. , Wong Jonathan P. , Siddiqui Yunus M. , Siddiqui Shahnaz 
Published: October 2006

AbstractA highly sensitive fluorogenic enzyme‐linked immunosorbent assay (FELISA) has been adapted for the detection of Vipera russelli venom. The assay sensitivity was observed to be 0.1 pg/ml (1 × 10−13 g/ml). Venoms from snakes of the Vipera group exhibited a high degree of cross‐reactivity when tested with the antibody raised against V. russelli venom. With the exception of venom from Naja naja, all the tested venoms from unrelated families also showed cross‐reactivity. This procedure is useful for detecting snake venom or its components in biological samples. © 1992 Wiley‐Liss, Inc.
“Lupinosis”‐Like lesions in mice caused by ustiloxin, produced by Ustilaginoieda virens: A morphological study
Authors: Nakamura Ken‐Ichi , Izumiyama Naotaka , Ohtsubo Koh‐Ichiro , Koiso Yukiko , Iwasaki Shigeo , Sonoda Ryouichi , Fujita Yoshikatsu , Yaegashi Hiroshi , Sato Zenji 
Published: October 2006

AbstractA crude toxin, obtained by methanol‐extraction of a water extract of false smut balls (INA‐KOUJI in Japanese) caused by Ustilaginoidea virens on rice panicles, was injected into mice intraperitoneally. Single injection of 100 or 200 mg/kg body weight of the extract was not lethal but caused acute, occasional necrosis of hepatocytes and renal tubular cells, followed by increased number of mitotic figures with occasional multinucleargiant cells. Erosions and ulceration of the forestomach and atrophy of the thymus were observed a week later. Repeated intraperitoneal injection of the crude toxin at the levels of 12 and 25 mg/kg body weight induced more severe necrosis of the liver and kidneys, with delayed occurrence of mitosis. Forestomach erosion also occurred. Serial injection for 10–12 days of either 3 or 6 mg/kg of the crude extract or 400 μg/kg of ustiloxin A, using the purified crystals, caused relatively mild but definite liver and kidney lesions similar to those described above. The lesions in the liver and kidney were quite similar to those observed in lupinosis caused by phomopsin A, a mycotoxin produced by Phomopsis leptostromiformis. Isolation of the toxic substance indicates that the contaminated rice panicles may cause toxicosis of cattle, although no field outbreaks have occurred yet. © 1994 wiley‐Liss, Inc.
Purification and characterisation of large and small maitotoxins from cultured gambierdiscus toxicus
Authors: Holmes Michael J. , Lewis Richard J. 
Published: October 2006

AbstractThree strains of cultured Gambierdiscus toxicus yielded distinct maitotoxins (maitotoxin‐1, ‐2, and ‐3) which were purified to homogeneity by high pressure liquid chromatography. Maitotoxins‐1 and ‐2 are large toxins (molecular weights for the sodium salts = 3,422 and 3,298, respectively), whereas maito‐toxin‐3 is relatively small (molecular weight = 1,060 for the sodium salt). The contractile actions on isolated guinea‐pig left atria, vas deferens and ilea of maitotoxins‐1 and ‐2 were compared with those of the small maitotoxin, maitotoxin‐3. Maitotoxin‐1, ‐2, and ‐3 each produced quantitatively similar, concentration‐dependent patterns of positive and negative inotropy in atria when compared on a mouse unit/ml basis (one mouse unit is the intraperitoneal LD50 dose for a 20 g mouse; the LD50 for maitotoxin‐2 = 0.08 μ g/kg). Concentrations of maitotoxin‐2 greater than 5 × 10−13 M caused positive inotropy. The three maitotoxins produced patterns of contractions in vas deferens and ilea that were qualitatively similar, including a period of prominent spike activity in vas deferens. On a mouse unit/ml basis, the order of potency on smooth muscle was maitotoxin‐1> maitotoxin‐3 > maitotoxin‐2. The contractile responses of smooth muscle to the maitotoxins were followed by an inhibitory phase where control agonist responses could not be elicited. The maitotoxin‐induced contractile responses of vas deferens were inhibited by nicardipine but not phentolamine, indicating that in this tissue, each maitotoxin has mainly a direct contractile effect that requires calcium influx through voltage‐sensitive calcium channels. The qualitatively similar in vitro (and in vivo) actions of the three toxins suggests that each maitotoxin has a similar mode of action, despite the considerable difference in their molecular size. The reduction in potency upon solvolysis of these maitotoxins suggests that sulphate moities are important for the biological activity of each maitotoxin. © 1994 wiley‐Liss, Inc.
Effects of low‐level dietary deoxynivalenol on haematological and clinical parameters of the pig
Authors: Prelusky Dan B. , Gerdes Robert G. , Underhill K. Lynne , Rotter Barbara A. , Jui Perry Y. , Trenholm H. Locksley 
Published: October 2006

AbstractThe subacute toxic effects of dietary deoxynivalenol (DON) were examined in grower pigs during a 32 day feeding period. DON was incorporated into the feed at 0,1, and 3 mg/kg, added as either the purified toxin (P) or as naturally contaminated corn (N). Growth performance and blood biochemical and haematological parameters were monitored throughout the study. At the higher toxin levels (diets 3P, 3N) significantly lower feed consumption and body weight gains were evident soon after the start of feeding, but while weight gains of pigs fed the pure DON diet (3P) recovered after several days, values for pigs fed the naturally contaminated diet (3N) remained depressed over the course of the study. It is possible that these observations reflected the presence of other unidentified toxic compounds in the naturally contaminated grain. Generally, blood chemistry parameters of pigs fed the contaminated diets were not different from controls, with the exception of α‐globulin and possibly cortisol in animals receiving diets 3N or 3P. Data suggested that the effect of DON on the a‐globulin fraction may have been independent of the feed refusal syndrome associated with this toxin. Alterations in several haematological measurements were noted to occur sporadically with the 3 ppm diets, including higher RBC count, haematocrit and platelet level, however these effects could not be separated from the influence of decreased feed intake and were of limited value in diagnosing the effects of low level dietary DON on swine. Published 1994 Wiley‐Liss, Inc.
Effects of pectenotoxin‐1 on liver cells in vitro
Authors: Zhou Zhen‐Hua , Komiyama Masatoshi , Terao Kiyoshi , Shimada Yutaka 
Published: October 2006

AbstractThe effects of pectenotoxin‐I (PTX1), a nondiarrheagenic toxin from mussels, on liver cells were investigated by fluorescence microscopy. The in vitro application of PTX1, to these cells induced reduction in number and loss in radial arrangement of microtubules. It also induced disruption of stress fibers and accumulation of actin at the cellular peripheries. Further studies are worthwhile to explore the feasibility of using PTX1, as a tool for analyzing the properties of cytoskeletal proteins. © wiley‐Liss, Inc.
Prevalence of exposure to aflatoxin and hepatitis B and C viruses in Guinea, West Africa
Authors: Diallo Mamadou S. , Sylla Abdoulaye , Sidibé Kaba , Sylla Bakary S. , Trepo Christian R. , Wild Christopher Paul 
Published: October 2006

AbstractThe prevalence of exposure to aflatoxin, hepatitis B virus (HBV), and hepatitis C virus (HCV), three important risk factors for hepatocellular carcinoma, was examined in Guinea, West Africa. A total of 75 sera were collected from men living in the Kindia region of lower Guinea. The sera were analysed by immunoassay of aflatoxin covalently bound to serum albumin as a marker of aflatoxin exposure. Over 90% of the sera contained detectable adduct levels, the hishest level being 385 pg aflatoxin B1‐lysine equivalent per mg albumin. Eleven subjects (14.7%) were positive for hepatitis B surface antigen in the serum and these subjects had a tendency to have higher aflatoxin‐albumin adduct levels than the other subjects (mean level 70.4 pg/mg compared to 44.1 pg/mg), but the difference was not statistically significant (P = 0.23). Eight subjects were positive for antibodies to HCV antigens and, interestingly, seven of these were from one ethnic group, Mandinka (25% prevalence). These data demonstrate that all three exposures are prevalent in Guinea and that the prevalence of these risk factors is comparable to that observed in other countries in West Africa. It is now important to assess the public health impact of these exposures in this country. © 1995 Wiley‐Liss, Inc.
microcystis aeruginosa: Behaviour and toxic features in San Roque Dam (Argentina)
Authors: Scarafia M. E. , Agnese A. M. , Cabrera J. L. 
Published: October 2006

AbstractM. aeruginosa is a cyanophyte frequently found in the water at the San Roque Dam (raw water supply conditioned for human use in Córdoba city) that causes a bad smell and taste, as well as potential toxic hazards of a still unknown extent. A heavy bloom tested by mouse bioassay (i.p.) for the first time on January 27, 1989, revealed toxicity. The dominant cyanobacterial species in the water sample was M. aeruginosa. The lyophilized bloom material (LD50: 14.5 mg/kg body weight) and the toxin isolated (LD50 estimated: 500 μg/kg), when administered to mice i.p., induced clinical signs similar to those induced by peptide toxins produced by M. aeruginosa. HPLC detected toxin traces from a sample of drinking water collected on the same day as the bloom. A seasonal follow‐up was carried out for the next 4 years in order to compare bloom toxicity values during the most significant water blooms; these never yielded LD50 values lower than 200 mg liophilized bloom material/kg of mice. © 1995 Wiley‐Liss, Inc.
Effect of different inhibitors of sterol biosynthesis on both fungal growth and aflatoxin production
Authors: Fanelli Corrado , Fabbri Anna Adele , Brasini Stefano , De Luca Chiara , Passi Siro 
Published: October 2006

AbstractAzole antifungals are reported to interfere with fungal growth by selective impairment of the P‐450 dependent 14 a‐demethylase system key to biosynthesis of ergosterol (ERG), thus leading to the depletion of this sterol in fungal membranes and to the accumulation of methylated precursors.We have investigated whether azole antifungals ketoconazole, miconazole, econazole, or itraconazole were able to modify the sterol and fatty acid patterns of a toxigenic strain of Aspergillus parasiticus, inducing the growth of mycelium depleted of ergosterol (ERG) and rich in less oxidisable sterols. It had been demonstrated that oxidation of ERG is correlated to aflatoxin biosynthesis. However, in this study no alteration of sterol or fatty acid patterns was observed after 7, 14, and 21 days of incubation of A. parasiticus in the presence of sublethal doses of azole antifungals. Specific production of aflatoxin was unaffected.Among the four antifungals tested, itraconazole was the strongest inhibitor of fungal growth and aflatoxin production while ketoconazole was the least effective. © 1995 Wiley‐Liss, Inc.
Induction of apoptosis by T‐2 toxin and other natural toxins in HL‐60 human promyelotic leukemia cells
Authors: Ueno Yoshio , Umemori Kiyoko , Niimi Eei‐Chi , Tanuma Sei‐Ichi , Nagata Satoshi , Sugamata Masao , Ihara Tomomi , Sekijima Masaru , Kawai Ken‐Ichi , Ueno Ikuko , Tashiro Fumio 
Published: October 2006

AbstractBased on the DNA fragmentation profile in gel electrophoresis and the morphological changes in electron microscopy, the induction of apoptotic nuclear changes by mycotoxins and other microbial products, in total 31 chemicals, was investigated in HL‐60 human promyelotic leukemia cells, along with the cytotoxicity tests with 3‐[4,5‐dimethylthiazol‐zyl]‐2,5‐diphenyltetrazolium bromide (MTT) and trypan blue exclusion. Among the chemicals tested, trichothecenes (T‐2 toxin, roridin A, nivalenol, deoxynivalenol), certain anthraquinones (luteoskyrin, skyrin, 2‐hydroxyemodin), diketopiperazines (emethallicin A, emestrin), isocoumarins (ochratoxin A, citrinin), lactone (penicillic acid), dihydrobisfuran (aflatoxin B), potassium ionophore (valinomycin), and an inhibitor of interleukin‐2 synthesis (cyclosporin A) were positive for the induction of DNA fragmentation. No DNA fragmentation was observed under the present conditions with fumonisin B1, cyclic peptides (cyclochlorotine, phalloidin, microcystin‐LR), certain anthraquinones (emodin, chrysophanol, rugulosin), and others (sterigmatocystin, cytochalasin A, griseofulvin, fusaric acid, kojic acid, rubratoxin B, butenolide, wortmannin, FK506, and sphingosine). The apoptotic changes in the cells exposed to T‐2 toxin and luteoskyrin were confirmed by electron microscopic observation. Detailed experiments on dose and time dependencies revealed that T‐2 toxin induced the apoptosis at 10 ng/ml (= 4 × 10‐8 M) levels within 2‐6 hr without significant cytotoxicity evaluated by the dye exclusion and MTT. © 1995 Wiley‐Liss, Inc.
Fate of a single dose of 14C‐labelled fumonisin B1 in vervet monkeys
Authors: Shephard Gordon S. , Thiel Pieter G. , Sydenham Eric W. , Savard Marc E. 
Published: October 2006

AbstractThe mycotoxin fumonisin B1 (FB1) was dosed as 14C‐labelled FB1 to male vervet monkeys (Cercopithecus aethiops) both by intravenous (iv) injection (2 monkeys, dose 1.72 mg [86 kBq]/kg body weight) and by gavage (2 monkeys, dose 6.42 mg [321 kBq]/kg body weight). Excreta were collected over a 24‐hr period, whereafter the monkeys were sacrificed and selected organs and contents of the gut collected to determine the distribution of the 14C‐label. The bulk of the radioactivity recovered from tissue was found in the liver (mean of 1.92% in iv‐dosed monkeys; 0.64% in gavage‐dosed monkeys). Of the other organs analysed, the following mean amounts of radioactivity were recovered in organs of iv‐ and savage‐dosed monkeys, respectively: muscle, 0.62% and 0.14%; kidney, 0.37% and 0.03%; brain, 0.08% and 0.02%; lung, 0.07% and 0.03%; heart, 0.04% and 0.01%; spleen, 0.02% and < 0.01%; plasma, 0.66% and 0.12%; red blood cells, 0.11% and 0.01%; while a further 68.1% and 64.0% were recovered in excreta, bile, and the gut contents. Analysis of faeces and gut contents showed that radioactivity was due to FB1, its partially hydrolysed metabolites, and trace amounts of the fully hydrolysed aminopentol moiety. Analysis of bile showed an absence of hydrolysis products, indicating that hydrolysis occurred only in the gut, resulting in the removal of the tricarballylic acid moiety at the C14‐position. Determination of FB1 levels in plasma following a gavage dose indicated that only limited amounts of FB1 were absorbed, as plasma levels peaked after 1‐2 hr with levels below 210 ng/ml. © 1995 Wiley‐Liss, Inc.
Toxicity and metabolism of ochratoxin A
Authors: Fink‐Gremmels Johanna , Jahn Andrea , Blom Maarten J. 
Published: October 2006

AbstractThe frequent occurrence of ochratoxin A (OA) in food and feed commodities and the high incidence of human exposure, as confirmed by different surveillance studies initiated several investigations devoted to elucidating the molecular mechanisms underlying OA toxicity. Previous studies indicated that the primary effects of OA are the inhibition of tRNA synthetase, the inhibition of mitochondrial respiration, and a disturbance of intracellular calcium homeostasis inherent to lipid peroxidation processes. We here report the effect of OA on a number of toxicological endpoints including cytotoxicity in different cell lines and effects on macromolecular synthesis and cell proliferation in primary cultures of hepatocytes at concentrations corresponding to overall exposure levels. These studies provide evidence that prominent toxicological effects might be linked to biotransformation processes. Analysis of hepatic biotransformation resulted in the detection of a number of distinct stable OA‐metabolites. As metabolic activation has also been identified as an essential step in OA mutagenicity, the biological relevance on this mechanistic data is discussed. © 1995 Wiley‐Liss, Inc.
BCR‐ and M&T‐activities in the area of mycotoxin analysis in food and feedstuffs
Authors: Boenke Achim 
Published: October 2006

AbstractIn order to avoid undesirable side effects such as high contents of mycotoxins in food and feed, measurements at critical steps of the food and feed production chain are performed. These measurements need to be accurate and precise to satisfy these aims. The accuracy and precision requirements to measurements form the basis of the Bureau Communautaire de Référence (BCR)‐and Measurements and Testing (M&T)‐Projects. Such projects aim to improve and/or develop analytical methodology, sampling plans, to harmonise agreement of results between European Union Member States and to prepare suitable certified reference materials (CRMs). The selection of the matrix CRMs and their corresponding level of mycotoxin contamination is made on the basis of requirements of the applied analytical procedures, stability requirements, regulations, norms, and inter‐or intra‐trade agreements which are in relation to quality specifications of imported and/or exported goods. The availability of appropriate matrix CRMs is not only a prerequisite for the implementation of directives and norms. It allows the validation of new methods and provides a possible solution to trade disputes, means for the statistical control of analytical results, tools for laboratory accreditation, and it is the basis for harmonisation and traceability of proficiency schemes. © 1995 Wiley‐Liss, Inc.