残杀威对舰艇蜚蠊的抗性调查与防制研究

目的：观察残杀威对德国小蠊的药效。方法：采用果酱瓶药膜法和现场试验评价效果。结果残杀威对德国小蠊敏感品系的平均KT50为13．86min，现场品系8个调查点的KT50为11．25—38．02min，对抗氯菊酯品系KT50为16．06-23．37min，72h死亡率均为100％；现场试验，4周后的杀灭率仍达90．58％。结论：残杀威对德国小蠊现场品系为一般击倒；对抗氯菊酯品系尚未形成交互抗性，其水乳剂防制舰艇蜚蠊效果满意。     

Induction of chromosmal aberrations in the syrian hamster by insecticides tested in vivo

The insecticides demeton, dimetoat, dichlorovos, endosulfan, trichlorofon, carbaryl, lindane, methoxychlor, propoxur and malathion were examined for their ability to induce chromosomal aberrations in the bone marrow cells of the Syrian hamster (Mesocricetus auratus) treated in vivo. Mutagenicity of commercial preparations was examined at four doses: LD₅₀; 1/2, 1/5 and 1/10 LD₅₀. The positive control was an IP injection of cyclophosphamide to hamsters at a dose of 40 mg/kg body wt. Demeton, dichlorovos and endosulfan gave positive results. Malathion, dimethoate and the mixture of methoxychlor and propoxur were weakly clastogenic; at some doses these compounds induced statistically significant increases in the number of aberrations. Trichlorfon and the mixture of carbaryl and lindane were negative in this test.This work was supported by the Polish Academy of Sciences within the projet 09.7.3.4.3     

Propoxur-induced oxidative DNA damage in human peripheral blood mononuclear cells: protective effects of curcumin and α-tocopherol

The present study enumerates the attenuating effects of curcumin and α-tocopherol against propoxur induced oxidative DNA damage in human peripheral blood mononuclear cells (PBMC). Cultured cells were isolated from peripheral blood of healthy volunteers, and were exposed to varying concentrations of propoxur (0–21?μg/ml) for 6, 12, and 24?h, and in combination with curcumin (9.2?μg/ml) or α-tocopherol (4.3?μg/ml) or both. Cytotoxic effect of propoxur was examined by MTT assay. The role of oxidative stress beneath the cytotoxicity of propoxur was evaluated by the measurement of reduced glutathione (GSH), malondialdehyde (MDA) and 8-hydroxy-2′-deoxyguanosine (8-OH-dG) levels in cell lysate. A concentration-dependent cell death, depletion of GSH, an increase in the level of both MDA and 8-OH-dG were observed. Co-treatment with curcumin or α-tocopherol significantly attenuates depleted GSH, decrease in MDA and 8-OH-dG levels in propoxur exposed cells (p?相似文献   

淡色库蚊残杀威抗性与酯酶活性的相关性研究

目的:检测抗残杀威品系各世代的抗性指数及蚊体内酯酶(esterase)的活性,探讨蚊虫抗性与酯酶的关系。方法:采用生物测定法和微板滴定法。结果:淡色库蚊经残杀威43 代的汰选,抗性指数达到11.26 倍;蚊体内的乙酰胆碱酯酶(acetylcholinesterase,AchE)活性的平均抑制率随世代的增加而变低,低于30%的个体频率随世代的增加而增加,呈相关关系;非特异性酯酶(nonspecificesterase,NSE)的活力随世代的增加而增强,而高于或等于0.9的个体频率逐渐增高,与生物测试法基本一致。结论:残杀威抗性与酯酶NSE和AchE的活性呈一定的相关关系。     

Comparative investigation of behavioral, neurotoxicological, and immunotoxicological indices in detection of subacute combined exposure with methyl parathion and propoxur in rats

The effects of 6 weeks of oral exposure to propoxur (PR; at doses of 0.851 and 8.51 mg/kg body wt.), methylparathion (MP; at doses of 0.218 and 0.872 mg/kg body wt.), and their combinations were investigated in male Wistar rats. Measurement endpoints of the investigation were certain general toxicological parameters (body weight gain, organ weights), plaque-forming cell (PFC) count from the spleen, open field (OF) behavior, auditory startle response (ASR), prepulse inhibition (PPI), rotarod performance, somatosensory and auditory cortical evoked potentials, and peripheral nerve conduction velocity. The treated rats did not show any sign of acute intoxication during the 6 weeks of exposure. The higher dose of PR, but not of MP, significantly decreased the relative liver weight. Both agents produced a significant dose-dependent increase of OF activity, with larger expression after 2 weeks than after 6 weeks. The number of ASR responses and the ASR amplitude increased. The amplitude after PPI was increased by MP but only minimally altered by PR and the combinations. There was a small, but with high-dose PR significant, increase in the latency of the somatosensory evoked potentials. Neither of the two substances alone had any effect on the PFC response. The effect of the combination of high-dose PR and low-dose MP was significantly different from that of high-dose PR alone on the liver weight, on the ASR amplitude, and on the PFC/10(6) cell and PFC/spleen counts. With high-dose MP and low-dose PR, no such interaction was observed. According to the results, the noneffective dose of MP can influence the toxicity of the effective dose of PR in a combined exposure situation.     

LW-特效灭蟑乳油的制备和稳定性研究

目的：以残杀威和高效氯氰菊酯为有效成分，制备LW-特效灭蟑乳油；方法：采用乳化实验法进行实验室药剂制备实验；结果：LW-特效灭蟑乳油经高低温储存试验，其乳油及乳状液的稳定性均达到国际粮农组织(FA0)规定的标准；结论：LW-特效灭蟑乳油物理性状稳定，使用方便，施药时气味低、痕迹小，有广泛的应用前景。     

The Effect of some Selected Pesticides on the Growth and Reproduction of Fresh Water <Emphasis Type="Italic">Oreochromis niloticus</Emphasis>, <Emphasis Type="Italic">Chrysicthys nigrodigitatus</Emphasis> and <Emphasis Type="Italic">Clarias gariepinus</Emphasis>

Studies were carried out to determine the toxicity of some selected pesticides on fresh water fish in a tropical environment. The uptake of the pesticides lindane, pentachlorophenol (PCP), and propoxur, which are frequently used on farms, and in industries as well as by loggers and timber men on wood were studied in concrete ponds at the University of Cape Coast, in Ghana. The fish used for the study were Oreochromis niloticus, Clarias gariepinus, and Chrysicthys nigrodigitatus. They were obtained from cultured ponds in the Cape Coast and Mankessim districts in the Central Region and Weija Dam, in the Greater Accra region of Ghana. Single high lethal concentration (SD) or acute treatment and cumulative/chronic (or multiple minor) lethal concentration (CD) treatment were employed in administering the pesticides to the fish via water. Gas chromatograph electron capture detector analysis was done on the dead fish to see the extent of ingestion. The LC₅₀ values obtained for lindane on the three fish samples were as follows: Chrysicthys – 0.38 mg L⁻¹; Oreochromis – 0.42 mg L⁻¹, and Clarias – 1.2 mg L⁻¹. Mortalities occurred in fish within 3–5 days of application. For the PCP on Chrysicthys, Oreochromis, and Clarias species the LC₅₀ values were 0.42, 0.32 and 0.64 mg L⁻¹, respectively, for over a 2- to 3-day period. For a three-time influx period of propoxur the LC₅₀ for Chrysicthys, Oreochromis, and Clarias, were 22.0, 30.40, and 45.04 (all in mg L⁻¹), respectively. The results obtained indicated that the pesticides had adverse effects on the general growth and reproduction of fish as shown by gonadosomatic indices.     

Effects of pesticides on human peripheral lymphocytes in vitro: induction of DNA damage

Because of the widespread use of pesticides for domestic and industrial applications the evaluation of their genotoxic effects is of major concern to public health. Although various experimental data have provided evidence that pesticides can possess genotoxic properties in animals and in in vitro test systems after acute and chronic exposure, the information on the genotoxic effects of some of pesticides is limited and inconsistent. In the present study, the genotoxic potential of commonly used pesticides (i.e., dimethoate and methyl parathion from the organophosphate class, propoxur and pirimicarb from carbamates, and cypermethrin and permethrin from pyrethroids) have been evaluated. The genotoxic effects of these substances were examined using the single cell gel electrophoresis (comet) assay in freshly isolated human peripheral lymphocytes. The cells were incubated with 10, 50, 100 and 200 µg/ml concentrations of the test substances for 0.5 h at 37°C and DNA damage was compared with that obtained in lymphocytes from the same donor not treated with substances. Hydrogen peroxide, 100 µM, was used as a positive control. Within the concentration ranges studied, no significant cytotoxic effects were observed. Dimethoate and methyl parathion at 100 and 200 µg/ml; propoxur at 50, 100 and 200 µg/ml, and pirimicarb, cypermethrin and permethrin at 200 µg/ml significantly increased DNA damage in human lymphocytes.     

Reversal of propoxur-induced impairment of step-down passive avoidance, transfer latency and oxidative stress by piracetam and ascorbic acid in rats

Propoxur, a carbamate pesticide has been shown to adversely affect memory and induce oxidative stress. The present study was designed to correlate the effect of propoxur, piracetam (a nootropic drug) and ascorbic acid (an antioxidant) on oxidative stress and cognitive function. Cognitive function was assessed using step-down latency (SDL) on a passive avoidance apparatus and transfer latency (TL) on elevated plus maze. Oxidative stress was assessed by examining brain malondialdehyde (MDA) and non-protein thiol (NP-SH) levels. A significant reduction in SDL and prolongation of TL was found for the propoxur-treated group at weeks 6 and 7 as compared with control (p < 0.001). One week treatment by piracetam (400 mg/kg/d, i.p.) or ascorbic acid (120 mg/kg/d, i.p.) antagonized the effect of propoxur on SDL as well as TL. Both piracetam and ascorbic acid attenuated the propoxur-induced increase in brain MDA levels and decrease in brain NP-SH levels. Results of the present study show that ascorbic acid and piracetam have the potential to reverse cognitive dysfunction and oxidative stress induced by propoxur in the brain.     

淡色库蚊对残杀威抗性机制的研究--酯酶与抗性的关系

为探讨酯酶与抗性的关系，采用生物测定法和微滴定板法，检测淡色库蚊抗残杀威品系各世代的抗性指数及蚊体现人酯酶的活性。淡色库蚊经过43代的汰选，抗性指数达到11.26倍；蚊体内的乙酰胆碱酯酶（AchE)活性的平均抑制率随世代的增加而变低，低于30%的个体频率随世代的增加而增加，呈正相关关系；非特异性酯酶（NSE）的活力随世代的增加而增强，而高于或等于0.9的个体频率逐渐增高，与生物测试法基本一致。抗残杀威品系AchE的不敏感性与抗性呈正相关关系，NSE的活力与抗性亦呈相关关系。