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1.
A barracuda implicated in ciguatera fish poisoning in Guadeloupe was estimated to have an overall flesh toxicity of 15 MUg/g using mouse bioassay. A lipid soluble extract was separated into two toxic fractions, FrA and FrB, on a LH20 Sephadex column eluted with dichloromethane/methanol (1:1). When intraperitoneal injected into mice, FrA provoked symptoms characteristic of slow-acting ciguatoxins, whereas FrB produced symptoms indicative of fast-acting toxins (FAT). High performance liquid chromatography/mass spectrometry/radio-ligand binding (HPLC/MS/RLB) analysis confirmed the two fractions were distinct, because only a weak overlap of some compounds was observed. HPLC/MS/RLB analysis revealed C-CTX-1 as the potent toxin present in FrA, and two coeluting active compounds at m/z 809.43 and 857.42 in FrB, all displaying the characteristic pattern of ion formation for hydroxy-polyethers. Other C-CTX congeners and putative hydroxy-polyether-like compounds were detected in both fractions, however, the RLB found them inactive. C-CTX-1 accounted for > 90% of total toxicity in this barracuda and was confirmed to be a competitive inhibitor of brevetoxin binding to voltage-sensitive sodium channels (VSSCs) with a potency two-times lower than P-CTX-1. However, FAT active on VSSCs and < 900 Da were suspected to contribute to the overall toxicity.  相似文献   

2.
In Florida (USA), numerous cases of human ciguatera fish poisoning, as well as neurotoxic shellfish poisoning following consumption of local seafood products, have been reported. By using in parallel, the sodium channel receptor binding assay (RBA), and the ouabain/veratridine-dependent cytotoxicity assay (N2A assay), we established criteria to identify, detect, and quantify ciguatoxins in fish extracts, with a brevetoxin as internal standard. Results showed that the Caribbean ciguatoxin C-CTX-1 exhibited an 8-fold higher potency in the RBA than brevetoxins and, a 440 and 2300-fold higher potency in the N2A assay than PbTx-1 and PbTx-3, respectively. Moreover, a sensitivity comparison between assays revealed that the N2A assay was more sensitive (12-fold) for ciguatoxin analysis, whereas the RBA was more sensitive (3-24-fold) for brevetoxins analysis. Based on the relative potency between toxins and the opposite sensitivity of both assays we have used the RBA and the N2A assay to screen great barracuda (Sphyraena barracuda) collected from the Florida Keys for ciguatoxins and brevetoxins. Fish extract analysis showed a sodium channel-dependent activity consistent with the presence of ciguatoxins, and not brevetoxins. Among 40 barracudas analyzed, 60% contained ciguatoxin levels in their liver measurable by the N2A assay with the most toxic fish containing 2.1ppb C-CTX-1 equivalents.  相似文献   

3.
BackgroundSome evidence in humans suggests that persistent organic pollutants (POPs), including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), may alter the blood lipid composition. This study analyzed associations between serum POPs concentrations in young adulthood with blood lipid levels up to 23 years later.MethodsSerum POPs were measured in year 2 of follow-up (n = 180 men and women, ages: 20-32y), and plasma lipids in follow-up years 2, 7, 10, 15, 20 and 25. 32 POPs were detectable in ≥75% of participants (23 PCBs, 8 OCPs and PBB-153). We created summary scores for PCBs and OCPs for both wet-weight, and lipid standardized (LP) concentrations. We used repeated measures regression adjusting for demographic factors, BMI, smoking, diabetes status, among others.ResultsWe observed positive associations of the 23 LP-PCB score with total cholesterol (βper SD increase [95%CI]: 5.0 mg/dL [0.7, 9.2]), triglycerides (7.8 mg/dL [-0.9, 16.5]), LDL (4.2 mg/dL [0.2, 8.2]), oxidized LDL 3.4 U/L (-0.05, 6.8), and cholesterol/HDL ratio (0.2 [0.02, 0.3]). The associations for triglycerides (14.7 mg/dL [0.4, 20.1]), cholesterol/HDL (0.33 [0.09, 0.56]) and, to some extent, LDL (4.7 md/dL [-1.6, 10.9]) were only observed among participants in the upper 50th percentile of BMI. Non-dioxin-like PCBs had stronger associations that dioxin-like PCBs. OCPs and PBB-s had positive associations with most outcomes.ConclusionsPCBs and PBB-153 measured in young adulthood were positively associated with prospective alterations in most blood lipid components, with evidence of effect modification by BMI. Further longitudinal studies with multiple measures of POPs overtime are needed.  相似文献   

4.
Transfer of organochlorine pesticides from mother to fetus has been studied in 100 women. The concentrations of organochlorine pesticides were examined in maternal blood, placenta, and umbilical cord blood of the same mother/child pair. Residue levels of dichlorodiphenyl trichloro ethane (DDT) and its metabolites, isomers of benzene hexachloride (BHC) and aldrin were detected in all the samples analyzed, indicating their transfer from mother to the fetus. A correlation was found to exist between the pesticide concentration and age, dietetic habits and area of residence of pregnant women.  相似文献   

5.
6.
We have studied the breeding parameters, organochlorine compounds (OCs) concentrations, and fatty acid (FA) composition of egg yolks (n = 47) and plasma (n = 90) of common terns (Sterna hirundo) from two colonies (Banya and Fangar) in the Ebro delta, NE Spain. Terns from Banya tend to have smaller clutch size and lower hatching success than terns from Fangar. p,p'-DDE and polychlorinated biphenyls (PCBs) concentrations were almost 2-fold higher in yolks from Banya in 1998 than from Fangar in 1999, and the percentage of n-6 PUFA was positively correlated with these contaminants. Differences between samplings in OCs concentrations in plasma were less evident, and were affected by breeding chronology. The highest OCs concentrations in yolks from Banya may be explained by two processes involving the increased deposition of n-6 PUFA: (1) higher mobilization of endogenous fat due to lower food resources, or (2) differences in the diet between colonies. Birds from Banya may have been feeding at a higher degree on discards of trawling fisheries composed of demersal and benthic fish species that are more exposed to contaminants from sediment and have lower n-3/n-6 ratio, whereas birds from Fangar would feed mostly on pelagic species of small clupeiformes that are less polluted and have higher n-3/n-6 ratios.  相似文献   

7.
张林林  薛健  许多武  彭非 《医药导报》2008,27(9):1104-1106
[摘要]目的对气相色谱分析动物药材水蛭、海马中17种有机氯农药残留量的方法进行适用性实验,并初步调查这两种动物药中农药残留的状况。方法从全国药材市场收集样品,样品以丙酮 石油醚(1:1)超声提取,提取液浓缩后用浓硫酸净化,采用DB 1701石英毛细管柱分离样品,GC ECD测定17种有机氯农药的残留量。结果17种农药2个水平的平均添加回收率分别为75.3%,88.1%。两种动物药中都检测到了农药残留,其中水蛭药材样品中的滴滴涕含量较高。结论该方法适用于动物药水蛭和海马中农药残留的测定,动物药中的残留农药污染和蓄积应引起重视。  相似文献   

8.
Exposure of pregnant women to organochlorine (OC) pesticides largely derives from contaminated food, but environmental, occupational, and domestic factors have also been implicated. We investigated the presence of nine OC residues in the umbilical cord blood of newborns in Southern Spain and analyzed the relationship of this exposure with maternal and pregnancy variables, including maternal adherence to the Mediterranean Diet (MD). OCs were detected in 95% of umbilical cord blood samples from the 318 mothers, who had a mean degree of adherence to the MD of 56.77 (SD: 16.35) (range, 0–100). The MD prioritizes consumption of vegetable and fruit over meat and dairy products, and OCs are generally lipophilic molecules that accumulate in foods of animal origin. Consumption of meat, fish, and dairy products was associated with dichlorodiphenyldichloroethylene (DDE) in umbilical cord serum, and dairy product intake with lindane. Vegetable consumption was also associated with lindane and fruit intake with endosulfan I. We found no significant association between MD adherence and the presence of OC residues in serum. However, closer adherence to the MD may offer greater protection against OC exposure because of its reduced content in meat and dairy products.  相似文献   

9.
目的:制定川白芷中有机氯类农药最大残留限量标准。方法:采用丙酮-水提取系统、二氯甲烷液-液分配、浓硫酸磺化净化除杂质的方法制备供试品溶液,毛细管气相色谱法(电子捕获检测器)检测川白芷中有机氯类农药的残留量。色谱柱为AgilentHP-5弹性石英毛细管(30m×0.32mm×0.25μm),进样口温度为230℃,检测器温度为300℃。结果:建议川白芷中有机氯类农药最大残留限量为:六六六(总BHC)不得超过0.05μg·g-1,滴滴涕(总DDT)不得超过0.05μg·g-1,五氯硝基苯(PCNB)不得超过0.01μg·g-1。结论:本试验可为生产绿色中药和保障用药安全提供科学依据。  相似文献   

10.
The present study reports unique data on concentrations of several classes of organochlorine pesticides and polychlorinated biphenyls in blubber biopsies from healthy living fin whales (Balaenoptera physalus) from the Gulf of California, Mexico, one of the most isolated and unstudied population in the world. OC levels in this population were generally lower than levels reported in fin whales from other regions. The rank order of OCs were ∑DDTs (range from 300 to 2400 ng g?1 lw) > ∑PCBs (range from 40 to 290 ng g?1 lw) > ∑HCHs (range from ?1 lw) ≥ ∑CHLORs (from < LOQ to 100 ng g?1 lw). The most abundant OC pesticide measured was the DDT metabolite, p,p′‐DDE. The PCBs 138, 153, and 180 were the most abundant PCBs congeners found in the fin whales samples. Males had significant higher concentrations of ∑OC, ∑DDTs and ∑PCBs than females (P < 0.05), although the p,p′‐DDE/∑DDTs ratios were similar between the sexes. Although the OC concentrations found in this population were generally below the levels that would be expected to cause deleterious health effects, the maximum values observed (2700 ng g?1 lw) in some animals were higher than those associated with reproductive effects in whales. Given the small population size and highly isolated characteristics of Gulf of California fin whales, health effects in individuals could readily translate into population‐level effects. Future research on this topic will be necessary to better understand the role that these compounds may have on the health of this population. © 2009 Wiley Periodicals, Inc. Environ Toxicol 25: 381–390, 2010.  相似文献   

11.
GC法检测浙八味药材中有机氯农药的残留   总被引:2,自引:0,他引:2  
目的 测定与分析白术、白芍、玄参等8种药材中9种有机氯农药残留量.方法 以混合溶剂超声提取样品、浓硫酸磺化净化,采用毛细管气相色谱,用HP-5弹性石英毛细管柱程序升温分离,微电子捕获检测器检测,峰面积外标法定量.结果 延胡索、麦冬和杭白菊均检出滴滴涕,含量分别为0.439、45.017、5.434 ng·g<'-1>;杭白菊检出五氯硝基苯,含量为1.030 ng·g<'-1>;其余药材均未检出有机氯农药残留.结论 浙八味药材大部分未检出有机氯农药残留或含量较低,均在规定的安全范围内.  相似文献   

12.
A bibliometric analysis based on the Web of Science© (WOS) database was performed on bioavailability of pesticides in vegetables, food or wine related studies published from inception to 2018. A total of 1202 articles were subjected to examination. The results reveal that yearly production of scientific articles increased steadily. Journal and institution production, and author's keywords frequencies followed the Lotka’s Law. Khan SU and White JC were the most productive authors. The most productive journals were Journal of Agricultural and Food Chemistry (55), and Journal of Ethnopharmacology (48), and the most common WOS subject category was Pharmacology & Pharmacy (419). USA (h-index of 40) produced 21.7 % of all articles, closely followed by China (20.6 %). Chinese Academy of Sciences (34) was the most productive research institutions. Finally, current and future trends in this area should focus on keywords such as pharmacokinetics, curcumin, in-vitro, nanoparticles, oral (bioavailability) and cell.  相似文献   

13.
The major advantage of primary neuronal cultures for developmental neurotoxicity (DNT) testing is their ability to replicate the crucial stages of neurodevelopment. In our studies using primary culture of cerebellar granule cells (CGCs) we have evaluated whether the gene expression relevant to the most critical developmental processes such as neuronal differentiation (NF-68 and NF-200) and functional maturation (NMDA and GABAA receptors), proliferation and differentiation of astrocytes (GFAP and S100β) as well as the presence of neural precursor cells (nestin and Sox10) could be used as an endpoint for in vitro DNT. The expression of these genes was assessed after exposure to various pesticides (paraquat parathion, dichlorvos, pentachlorophenol and cycloheximide) that could induce developmental neurotoxicity through different mechanisms. All studied pesticides significantly modified the expression of selected genes, related to the different stages of neuronal and/or glial cell development and maturation. The most significant changes were observed after exposure to paraquat and parathion (i.e. down-regulation of mRNA expression of NF-68 and NF-200, NMDA and GABAA receptors). Similarly, dichlorvos affected mainly neurons (decreased mRNA expression of NF-68 and GABAA receptors) whereas cycloheximide had an effect on neurons and astrocytes, as significant decreases in the mRNA expression of both neurofilaments (NF-68 and NF-200) and the astrocyte marker (S100β) were observed. Our results suggest that toxicity induced by pesticides that target multiple pathways of neurodevelopment can be identified by studying expression of genes that are involved in different stages of cell development and maturation, and that gene expression could be used as a sensitive endpoint for initial screening to identify the compounds with the potential to cause developmental neurotoxicity.  相似文献   

14.
The results from a survey of the expert information that is publicly accessible on the use of the dog as test species during the regulatory evaluation of agricultural chemicals and pesticides are reported. Methods that are being used or considered in order to reduce the number of dogs used for this purpose are described. Regulatory evaluation aims at establishing threshold values for safe human exposure; it is based on no-observed-adverse-effect levels (NOELs) determined in animal studies. Current regulations require testing in two species, a rodent species (usually rat or mouse), and a non-rodent species (usually the dog). Subchronic (90-day) and chronic (12-month) repeated-dose feeding studies must be routinely conducted in dogs. This report first focuses on the results from a retrospective study analysing data on 216 pesticides kept on record by the Bundesinstitut für Risikobewertung, BfR (German Federal Institute for Risk Assessment), the competent regulatory authority in Germany. The study was sponsored and coordinated by SET, the German Foundation for the Promotion of Research on Replacement and Complementary Methods to Reduce Animal Testing (Stiftung zur Förderung der Erforschung von Ersatz-und Ergänzungsmethoden zur Einschränkung von Tierversuchen, Mainz) and conducted by the BfR. Since the data submitted for registration of a product is the property of the manufacturer, the study could only proceed with the collaboration of the German Association of Manufacturers of Agricultural Chemicals (Industrieverband Agrar, IVA). To ensure confidentiality, designated codes were used instead of the compounds proper names when the study was published. The results support two major conclusions. The use of the dog for the testing of pesticides is indeed necessary because the dog has proved to be the most sensitive species for about 15% of the compounds examined. However, chronic studies are only of limited value since they only provide essential information that cannot be obtained in sub-chronic studies in about 5% of cases. These conclusions are supported by several retrospective analyses using data on pharmaceutical drugs carried out in the context of the International Conference on Harmonisation of Technical Requirements for the Registration of Pharmaceuticals for Human Use (ICH). Over 90% of drugs elicited no toxic symptoms in 12-month studies in dogs in addition to those that had been recorded previously in studies conducted for 90 or 180 days in dogs and rats. Another approach comparing the results from pre-clinical animal studies with clinical studies noted that animal studies predicted about 70% of the effects observed in volunteers, and in about 94% of cases the effects occurred in animal studies lasting not more than one month. Furthermore, the report summarises the current methods under consideration that could refine or reduce the use of dogs in toxicity testing: industrial data sharing and harmonisation of guidelines, in vitro methods, human studies, computational prediction models, and integrated testing approaches. The integrated Agricultural Chemicals Safety Assessment (ACSA) testing scheme, which is currently being developed in an international project initiated by the International Life Sciences Institute (ILSI, USA), is of particular relevance, since an ambitious attempt is being made to design a new comprehensive test framework incorporating modern scientific approaches and covering most aspects of current regulatory testing requirements. The ACSA project has access to the pesticide database of the US EPAs Office of Pesticide Programs (OPP). Preliminary results have confirmed the two major conclusions from the joint SET/BfR study conducted in Germany. Taking these results into account, it is recommended that the regulatory requirement for 12-month studies to be routinely carried out in dogs should be abandoned. While 90-day studies should be conducted in both rats and dogs, chronic studies should only take place in rats. If the dog is more sensitive than the rat in the 90-day study, an additional safety factor to the NOEL value obtained in the chronic rat study should be applied in order to set the threshold for safe human exposure, instead of conducting a 12-month study in dogs. This safety factor may be calculated from chronic NOEL data available in several pesticide databases. Chronic tests using dogs would then only be required if the test compound belongs to a new class of chemicals that has never been tested before. Thus, the report concludes that, according to current scientific knowledge, the routine 12-month studies in dogs are no longer required for agricultural chemicals and pesticides, and international regulations should be changed accordingly. Active international support of such measures is welcomed, from both an economical and an animal welfare perspective.Electronic Supplementary Material Supplementary material is available for this article at  相似文献   

15.
Ciguatera fish poisoning (CFP) is endemic in certain tropical and subtropical regions of the world. CFP had not been described on the West Africa Coast until a 2004 outbreak in the Canary Islands. In 2008–2009, two additional outbreaks of ciguatera occurred. Individuals afflicted had consumed lesser amberjack (Seriola rivoliana) captured from nearby waters. Caribbean ciguatoxin-1 (C-CTX-1) was confirmed in fish samples by LC-MS/MS. Ciguatoxic fish in this region may pose a new health risk for the seafood consumer.  相似文献   

16.
The effects of DDT, DDE, DDOH and DDA on the oxidation of NADH, glutamate, -hydroxybutyrate and sucoinate by rat liver mitochondria were investigated. The influence of these compounds on the activity of purified liver glutamate dehydrogenase was also checked. It was found that DDT and all those of its metabolites investigated inhibited oxidation of NAD-linked substrates by both intact and sonicated mitochondria. The water-soluble metabolites of DDT (DDOH and DDA) stimulated succinate oxidation by intact but not by sonicated mitochondria, and inhibited the activity of glutamate dehydrogenase. It is concluded that DDT and its metabolites may affect mitochondrial respiratory chain between NADH and CoQ, inhibit glutamate dehydrogenase, and uncouple oxidative phosphorylation.  相似文献   

17.
Elevated inflammation is a known risk factor in the pathogenesis of PTB. Despite intensive research, the etiology of idiopathic PTB is still unknown. The present study was designed to explore associations of blood concentrations of organochlorine pesticides (OCPs) with inflammatory/antioxidant gene expression, and cytokines and prostaglandin levels in PTB cases. Significantly high levels of α, β-hexachlorocyclohexane (α, β-HCH), dichlorodiphenyldichloroethane (o’p’-DDD), dichlorodiphenyldichloroethylene (p’p’-DDE), increased expression of cyclooxygenase-2 (COX-2), and decreased expression of manganese superoxide dismutase (Mn-SOD) and catalase (CAT) genes were seen in PTB cases. Also, increased protein levels of interleukin-6 (IL-6) and decreased protein levels of interleukin-4 (IL-4) and prostaglandin F2α (PGF2α) were found in maternal blood of PTB cases as compared to term controls. Elevated levels of β-HCH along with high expression of COX-2 gene or low expression of Mn-SOD or CAT genes were associated with the decrease in the period of gestation (POG).  相似文献   

18.
This study investigated the levels of 20 congeners of polychlorinated biphenyls (PCBs), including toxic dioxin-like PCBs and 7 organochlorine pesticides (OCPs) in 33 human milk samples collected in 2011 from multiparae living in Zadar, Croatia. Concentrations of ∑PCBs, ∑DDTs, ∑HCHs and HCB in samples ranged from 11.7 to 146.3, 8.7 to 89.2, 0.9 to 28.4, and <LOD to 8.0 ng g−1 milk fat, respectively. PCB congeners −153, −138, −180 and −170 dominated in the PCB profiles, while p,ṕ-DDE was the most abundant OCP. PCB-126 was the most abundant non-ortho PCB, while among mono-ortho PCBs, the congeners −118, −105 and −156 equally contributed to the mono-ortho PCB fraction. TEQs for dl-PCBs ranged between 0 and 13.3 pg g−1 milk fat. The calculated estimated daily intakes for all compound groups were below the tolerable daily intake indicating no risk for breastfed infants. A comparison of our results with our previous study on primiparae revealed that the concentrations of the main contaminant groups are lower in the milk of multiparae, with the exception of toxic mono-ortho PCBs whose concentrations and TEQ remained similar among the groups, and HCB whose concentrations were found to be higher in multiparae. Concentrations of PCBs and OCPs found in the samples from this study did not exceed those from other parts of the world. This study revealed that there are differences in contaminant concentrations depending on the mothers’ parity and that this fact should be taken into account when risk assessment studies are conducted.  相似文献   

19.
DDT is a highly lipophilic molecule known to deplete membrane rafts of their phosphoglycolipid and cholesterol contents. However, we have recently shown that DDT can also alter the thyroid homeostasis by inhibiting TSH receptor (TSHr) internalization. The present study was undertaken to verify whether DDT goitrogenic effects are due to the insecticide acting directly on TSHr or via alteration of the membrane rafts hosting the receptor itself. Our results demonstrate that, in CHO-TSHr transfected cells, TSHr is activated in the presence of TSH, while it is inhibited following DDT exposure. DDT can also reduce the endocytic vesicular traffic, alter the extension of multi-branched microvilli along their plasma membranes and induce TSHr shedding in vesicular forms. To verify whether TSHr displacement might depend on DDT altering the raft constitution of CHO-TSHr cell membranes the extent of TSHr and lipid raft co-localization was examined by confocal microscopy. Evidence shows that receptor/raft co-localization increased significantly upon exposure to TSH, while receptors and lipid rafts become dislodged on opposite cell poles in DDT-exposed CHO-TSHr cells. As a control, under similar culturing conditions, diphenylethylene, which is known to be a lipophilic substance that is structurally related to DDT, did not affect the extent of TSHr and lipid raft co-localization in CHO-TSHr cells treated with TSH. These findings corroborate and extend our view that, in CHO cells, the DDT disrupting action on TSHr is primarily due to the insecticide acting on membranes to deplete their raft cholesterol content, and that the resulting inhibition on TSHr internalization is due to receptor dislodgement from altered raft microdomains of the plasma membrane.  相似文献   

20.
The present study aimed to evaluate the protective effect of protexin supplementation against chlorpyrifos-induced oxidative stress and immunotoxicity in Cyprinus carpio. After 21 days, the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR), and total antioxidant levels significantly decreased in hepatocytes of fish exposed to chlorpyrifos, while malondialdehyde (MDA) increased. Treatment with protexin was able to reverse the decrease in SOD and GR and significantly reduce MDA levels. Exposure to chlorpyrifos also induced alterations in blood biochemical parameters and caused immunosuppression. Dietary protexin return some parameters (aspartate aminotransferase, lactate dehydrogenase, and γ-glutamyltransferase activities, and glucose, cholesterol, total protein, creatinine, and complement C4 levels) to values similar to those of the control group. Based on the results, it can be concluded that protexin exerted protective effects against chlorpyrifos exposure in C. carpio reducing oxidative damage, and ameriorating blood biochemical alterations and the immunosuppression.  相似文献   

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