Natural toxins最新文献_第2页

Phytotoxic lignans of Leucophyllum frutescens. 白叶的植物毒性木脂素。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/(sici)1522-7189(199902)7:1<39::aid-nt38>3.0.co;2-2

A M Rimando, F E Dayan, J R Mikell, R M Moraes

引用次数: 30

Mechanisms underlying the hemolytic and ichthyotoxic activities of maitotoxin. maitotoxin的溶血和鱼毒作用机制。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/(sici)1522-7189(199903/04)7:2<71::aid-nt40>3.0.co;2-0

T Igarashi, S Aritake, T Yasumoto

{"title":"Mechanisms underlying the hemolytic and ichthyotoxic activities of maitotoxin.","authors":"T Igarashi, S Aritake, T Yasumoto","doi":"10.1002/(sici)1522-7189(199903/04)7:2<71::aid-nt40>3.0.co;2-0","DOIUrl":"https://doi.org/10.1002/(sici)1522-7189(199903/04)7:2<71::aid-nt40>3.0.co;2-0","url":null,"abstract":"Maitotoxin (MTX), a putative Ca(2+) channel activator produced by the dinoflagellate Gambierdiscus toxicus showed extremely potent hemolytic and ichthyotoxic activities. Hemolysis of 1% mouse blood cell suspension in saline occurred at 15 nM of MTX. The activity was enhanced six-fold in the presence of 10 microM of Ca(2+) and completely blocked by EDTA2Na, indicating its dependency on external Ca(2+). The MTX-induced hemolysis was little affected by L-type Ca(2+) channel blockers (diltiazem, nifedipine, verapamil) but was strongly inhibited by calmodulin blockers (prenylamine and chlorpromazine) or a phospholipase A2 inhibitor (quinacrine). MTX was mimicked by a calcium ionophore, calcimycin. Based on these results, a series of cellular events triggered by MTX were presumed to occur in the following sequence: increased Ca(2+) entry in cells, activation of calmodulin, promotion of phospholipase A2 activity, and finally destruction of cell membrane resulting from hydrolysis of membrane lipids. The sensitivity of blood cells to MTX varied significantly, dependent on the animal sources. Nucleated blood cells of carps and chickens were 100 times more resistant than those of mammals. LC(50) of MTX to freshwater fish Tanichthys albonubes in Ca(2+) free media (pH 8) was 5 nM but was markedly lowered to 3 pM by raising pH to 8 and increasing Ca(2+) concentration to 2 mM. In a marine environment MTX was 2000 times more toxic to fish than 42-di-hydrobrevetoxin-B (PbTx-3), one of the best known ichthyotoxins of red-tide origins.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"7 2","pages":"71-9"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21358903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 45

Brevetoxin B4 isolated from greenshell mussels Perna canaliculus, the major toxin involved in neurotoxic shellfish poisoning in New Zealand. 从绿壳贻贝(Perna canaliculus)中分离的Brevetoxin B4，是纽西兰造成贝类神经毒性中毒的主要毒素。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/(sici)1522-7189(199903/04)7:2<45::aid-nt34>3.0.co;2-h

A Morohashi, M Satake, H Naoki, H F Kaspar, Y Oshima, T Yasumoto

引用次数: 73

The possible involvement of 3-methoxy-2(5H)-furanone in the etiology of Narthecium asiaticum maxim. associated nephrotoxicity in cattle. 3-甲氧基-2(5H)-呋喃酮可能参与亚洲麻黄病的发病机制。牛的相关肾毒性。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/1522-7189(199911/12)7:6<317::aid-nt73>3.0.co;2-6

A Flåøyen, T L Torgersen, W Langseth

引用次数: 0

Effects of temperature, incubation period and substrate on production of fusaproliferin by Fusarium subglutinans ITEM 2404. 温度、孵育时间和底物对粘质镰刀菌产褐藻素的影响

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/(sici)1522-7189(199907/08)7:4<129::aid-nt53>3.0.co;2-u

G Castellá, G P Munkvold, P Imerman, W G Hyde

引用次数: 17

Effects of endotoxin and tumor necrosis factor alpha on regional brain neurotransmitters in mice. 内毒素和肿瘤坏死因子对小鼠脑区域神经递质的影响。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/1522-7189(200009/10)7:5<187::AID-NT58>3.0.CO;2-1

L Cho, M Tsunoda, R P Sharma

{"title":"Effects of endotoxin and tumor necrosis factor alpha on regional brain neurotransmitters in mice.","authors":"L Cho, M Tsunoda, R P Sharma","doi":"10.1002/1522-7189(200009/10)7:5<187::AID-NT58>3.0.CO;2-1","DOIUrl":"https://doi.org/10.1002/1522-7189(200009/10)7:5<187::AID-NT58>3.0.CO;2-1","url":null,"abstract":"Alterations in regional brain concentration of dopamine (DA), norepinephrine (NE), serotonin (5-HT) and their metabolites were investigated in male BALB/c mice injected intraperitoneally with bacterial lipopolysaccharide (LPS, 2 mg kg(-1)) or recombinant murine tumor necrosis factor alpha (TNFalpha, 0.1 mg kg(-1)) at 2, 6, 12 and 24 h after the injection. At 2 h post-injection the LPS administration resulted in hypothermia, which was not apparent at later time points. No consistent effects were observed by either LPS or TNFalpha on peripheral leukocyte counts or plasma transaminase levels. Both LPS and TNFalpha slightly elevated NE metabolism in the striatum at 2-12 h. Concentrations of DA and its metabolites were significantly elevated only in the hypothalamus following TNFalpha at 24 h. Tumor necrosis factor alpha exerted pronounced effects on 5-HT metabolism in most brain regions at 2 h. Results suggest that the effect of LPS is more complex compared with TNFalpha because of the endogenous production of other cytokines including the TNFalpha.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"7 5","pages":"187-95"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1522-7189(200009/10)7:5<187::AID-NT58>3.0.CO;2-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21783216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 17

Detection of domoic acid in northern anchovies and California sea lions associated with an unusual mortality event. 在北部凤尾鱼和加利福尼亚海狮中发现软骨藻酸与不寻常的死亡事件有关。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/(sici)1522-7189(199905/06)7:3<85::aid-nt39>3.0.co;2-q

K A Lefebvre, C L Powell, M Busman, G J Doucette, P D Moeller, J B Silver, P E Miller, M P Hughes, S Singaram, M W Silver, R S Tjeerdema

{"title":"Detection of domoic acid in northern anchovies and California sea lions associated with an unusual mortality event.","authors":"K A Lefebvre, C L Powell, M Busman, G J Doucette, P D Moeller, J B Silver, P E Miller, M P Hughes, S Singaram, M W Silver, R S Tjeerdema","doi":"10.1002/(sici)1522-7189(199905/06)7:3<85::aid-nt39>3.0.co;2-q","DOIUrl":"https://doi.org/10.1002/(sici)1522-7189(199905/06)7:3<85::aid-nt39>3.0.co;2-q","url":null,"abstract":"The occurrence of an unusual mortality event involving California sea lions (Zalophus californianus) along the central California coast in May 1998 was recently reported. The potent neurotoxin domoic acid (DA), produced naturally by the diatom Pseudo-nitzschia australis and transmitted to the sea lions via planktivorous northern anchovies (Engraulis mordax), was identified as the probable causative agent. Details of DA analyses for anchovy tissues and sea lion feces are described. Domoic acid levels were estimated in anchovy samples by HPLC-UV, and in sea lion feces using the same method as well as a microplate receptor binding assay, with absolute confirmation by tandem mass spectrometry. The highest DA concentrations in anchovies occurred in the viscera (223 +/- 5 microg DA g(-1)), exceeding values in the body tissues by seven-fold and suggesting minimal bioaccumulation of DA in anchovy tissue. HPLC values for DA in sea lion fecal material (ranging from 152 to 136.5 microg DA g(-1)) required correction for interference from an unidentified compound. Inter-laboratory comparisons of HPLC data showed close quantitative agreement. Fecal DA activity determined using the receptor binding assay corresponded with HPLC values to within a factor of two. Finally, our detection of P. australis frustules, via scanning electron microscopy, in both anchovy viscera and fecal material from sea lions exhibiting seizures provides corroborating evidence that this toxic algal species was involved in this unusual sea lion mortality event.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"7 3","pages":"85-92"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21502546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 221

Relative inhibition of insect phenoloxidase by cyclic fungal metabolites from insect and plant pathogens. 昆虫和植物病原菌循环真菌代谢物对昆虫酚氧化酶的相对抑制作用。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/1522-7189(199911/12)7:6<337::aid-nt69>3.0.co;2-o

P F Dowd

引用次数: 47

Methodological improvement of the protein phosphatase inhibition assay for the detection of okadaic acid in mussels. 贻贝中冈田酸蛋白磷酸酶抑制法的方法学改进。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/1522-7189(199911/12)7:6<387::aid-nt87>3.0.co;2-n

R Della Loggia, S Sosa, A Tubaro

引用次数: 23

Monitoring brevetoxins during a Gymnodinium breve red tide: comparison of sodium channel specific cytotoxicity assay and mouse bioassay for determination of neurotoxic shellfish toxins in shellfish extracts. 短绒裸子赤潮期间短绒毒素的监测:钠通道特异性细胞毒性测定法与小鼠生物测定法测定贝类提取物中神经毒性贝类毒素的比较。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/(sici)1522-7189(199907/08)7:4<157::aid-nt52>3.0.co;2-#

R Dickey, E Jester, R Granade, D Mowdy, C Moncreiff, D Rebarchik, M Robl, S Musser, M Poli

{"title":"Monitoring brevetoxins during a Gymnodinium breve red tide: comparison of sodium channel specific cytotoxicity assay and mouse bioassay for determination of neurotoxic shellfish toxins in shellfish extracts.","authors":"R Dickey, E Jester, R Granade, D Mowdy, C Moncreiff, D Rebarchik, M Robl, S Musser, M Poli","doi":"10.1002/(sici)1522-7189(199907/08)7:4<157::aid-nt52>3.0.co;2-#","DOIUrl":"https://doi.org/10.1002/(sici)1522-7189(199907/08)7:4<157::aid-nt52>3.0.co;2-#","url":null,"abstract":"In October of 1996, a Gymnodinium breve bloom occurred in shellfish harvesting waters of Alabama, Mississippi and Louisiana, Gulf of Mexico, USA. Bloom densities reached 5.6x10(5) cells liter(-1) and bloom residence at shellfish sampling stations ranged from 3 to 28 days. Brevetoxin-2 dominated G. breve toxin profiles in bloom seawater extracts. Shellfish toxicity, assessed by mouse bioassay, exceeded the guidance level for up to 75 days after the bloom had dissipated. Cytotoxicity assays and mouse bioassays showed similar temporal patterns of shellfish toxicity, but the two methods differed in estimations of brevetoxin-3 equivalent toxicity by a factor of 93 to 1. LC-ESI-MS showed the temporal patterns in shellfish toxicity reflected metabolism of G. breve toxins. The molecular ions m/z 1004, 1017 and 1033 dominated LC-ESI-MS spectra of toxic chromatographic fractions from the extracts and were identified as brevetoxin metabolites on the basis of LC-APCI-MS-MS. The discrepancy between cytotoxicity and mouse bioassay estimates of brevetoxin-3 equivalent toxicity resulted from the difference in extraction efficiency of solvents used in the respective methods and the relative sensitivity of the assays to toxin metabolite mixtures present in the extracts. The normalized cytotoxicity assay showed 75% agreement with mouse bioassay positive test samples and 64% agreement with mouse bioassay negative test samples. Published in 1999 by John Wiley & Sons, Ltd.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"7 4","pages":"157-65"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21644811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 106