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991.
The present study aims to determine the concentrations of Cd, Cu, Fe, Ni, Pb, and Zn in the different tissues of five species of tropical intertidal gastropods from Malaysia. Each of the species have organs/tissues that highly accumulated certain metals. For Cu, the mantles of Cerithidea obtusa, Pugilina cochlidium, and Murex trapa; and the digestive caeca of Thais sp. and Chicoreus capucinus highly accumulated Cu. The shells of Chi. capucinus and M. trapa, the digestive caeca of P. cochlidium, and the digestive glands of Thais sp. and Chi. capucinus highly accumulated Cd. The tentacles and the digestive caeca of Cer. obtusa and P. cochlidium, respectively, highly accumulated Zn, the digestive glands of Thais sp., Chi. capucinus, and M. trapa also highly accumulated Zn. The shells of most of the gastropods accumulated high levels of Pb and Ni. The opercula of most of the gastropods, besides the digestive glands for Thais sp., accumulated high levels of Fe. The present study on interspecific variations of heavy metals in gastropods provided information on differences of metal distributions in the different tissues, which could be useful in proposing potential tissues as better biomonitoring tools of heavy metal bioavailabilities in the coastal waters of Peninsular Malaysia. 相似文献
992.
O. Adeyemi G.S. Adenitire O.B. Oloyede A.T. Oladiji O.M. Oluba O. Adeyemi 《毒物与环境化学》2013,95(7):1347-1356
A study was performed to evaluate the effect of contaminated water on the tissues of Rattus novergicus (albino rats). Test rats were given water contaminated with lead (0.015 µg L?1 tap water), phenol (0.05 mL L?1 tap water), and benzene (0.05 mL L?1 tap water), while control rats were given tap water over a period of 65 days after which the activity of selected enzymes of the heart and serum was assayed, and hematological parameters and serum lipid profiles were also determined. Generally, a significant (p < 0.05) drop in the activity of the enzymes was observed in the heart of test rats relative to the control rats. However, the serum activities increased significantly in the test group compared to the control group (p < 0.05). The concentrations of serum cholesterol, low-density lipoprotein (LDL), and triglycerides of the test rats were found to be significantly higher than those of the control rats (p < 0.05). Concentrations of hemoglobin, red blood cell count, and packed cell volume of test rats were observed to be significantly lower than those of the control rats (p < 0.05). The experimental results indicated that consumption of water contaminated with lead, phenol, and benzene may damage the heart, increase the risk of atherosclerosis as reflected by the serum lipid profile, and anemia as suggested by abnormal hematological properties. 相似文献
993.
Jonathan E. Naile Jong Seong Khim Jessica N. House Paul D. Jones John P. Giesy 《毒物与环境化学》2013,95(7):1219-1232
It has been reported that the relative response factors of isotopically labeled standards and unlabeled standards of the same perfluorinated compounds could be different. Individual (100 ng mL?1) solutions of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were analyzed using high-performance liquid chromatography tandem mass-spectrometry under negative-ion electrospray to detect any impurities present down to 0.5%–0.1% relative to the major component. Purity of the standards ranged from approximately 86% to ≥ 97%. Standard solutions of unlabeled and isotopically labeled materials were analyzed to compare the response factors of isotopically labeled analytes versus their nonlabeled counterparts in three different matrices at equivalent concentrations: organic solvent (methanol), serum extract, and water present individually and concurrently. Not all labeled analytes have the same response factor as their nonlabeled complement, and in at least one case the matrix in which the standard is present may cause significant suppression of response. Standard solutions of electrochemical fluorination produced PFOA and PFOS were quantified under multiple reaction monitoring mode, using calibration curves prepared from standards consisting primarily of linear standards only. The use of linear only standards may cause under-prediction of concentrations, and that the working range of these standards may be limited. 相似文献
994.
Reports on Gulf War illness (GWI) implicated the use of the pesticide permethrin (PER), and the insect repellent N,N-diethyl-m-toluamide (DEET), in its etiology, as well as pyridostigmine bromide (PB), which was given as a prophylactic treatment against nerve agent exposure. Using Affymetrix microarrays the genomic response of human neuronal SHSY-5Y cells to 10 days of exposure to these agents was characterized and profiles of gene modulation unique to each treatment were demonstrated. In particular, a significantly greater impact of PER was observed compared to the other treatments. The Ingenuity Pathway Analysis knowledgebase was used to analyze the genomic datasets and attribute functional consequences to the effects of related genes, which were significantly up- or down-regulated in response to different treatments. Canonical pathways shown to be significantly modulated at the genomic level in response to exposure included cellular mechanisms, which might contribute to the clinical presentation in GWI patients and thus be targeted for further investigation as potential targets for therapeutic intervention. 相似文献
995.
Biological activity of neem seeds, leaves and bark is well-established as feeding deterrent and growth disrupter against insects and other arthropods. Neem is a valuable natural pesticide with low toxicity for vertebrates. However, it has not yet achieved a prominent place among pesticides due to its unstability. Recent studies have focused on newer formulations like microencapsulation, inclusion complexes, microemulsion, and granular formulations to enhance efficacy shelf life. Several studies have been undertaken on the effects of neem on predator, parasitoids, and other beneficial organisms as well as impact on the environment. Biotechnological interventions have been carried out for mass production of the active molecule. Once stable formulations of the active molecules are developed, the farming community will benefit the most due to the low toxicity and marked efficacy of neem insecticides. 相似文献
996.
M.S. Hassanvand K. Naddafi R. Nabizadeh F. Momeniha A. Mesdaghinia K. Yaghmaeian 《毒物与环境化学》2013,95(8):1636-1642
The hazardous waste management (HWM) practice at Tehran University of Medical Sciences Central Campus, Iran, was investigated in this study. Four schools were selected and the required information such as type and amount of wastes, temporary storage methods, waste discharge frequency, and final waste disposal methods using sampling, questionnaires, interviews with laboratory staff, and reference to available documents were gathered. The quantity of hazardous waste generation per year excluding the uncontrolled wastewater was found to be 2.072 tons per year. The obtained results show that wastes having features of being infectious, toxic, ignitable, carcinogenic, corrosive, and reactive were present at 32%, 28%, 16%, 14%, 8%, and 2%, respectively. In the central campus, hazardous solid wastes managed with household solid wastes and hazardous liquid waste were discharged into the sinks without any kind of control; improper HWM practices are evident from the point of waste production to final disposal. 相似文献
997.
A.M. Hegazy H.H. Bakry R.M. El-Shawarby M.E. Abou-Salem N.M. Abd El-Aleem 《毒物与环境化学》2013,95(1):136-145
This study was carried out to investigate the effect of long-term exposure to benzo(a)pyrene (B(a)P) in mice. Hemogram, tumor markers, oxidative status, and B(a)P residues in liver tissue were evaluated. Sixty albino Swiss mice were randomly distributed equally into three groups; the control was given 0.1?mL corn oil once a week for 8 weeks. The other two groups were given 20 and 40?mg B(a)P per kg body weight once a week orally for the same period. B(a)P-treated mice suffered from depression and ascites, and macrocytic normochromic anemia was recorded at the 16th and 30th week. There was marked leukocytosis with lymphocytosis at the early stage of the experiment, followed by leukopenia, lymphopenia, and neutropenia at the end of the experiment. Monocytes and arginase activity were elevated throughout the experiment. Alpha feto-protein was detected only in the experimental groups in the 30th week of the experiment. A marked increase in lipid peroxides associated with a decrease in reduced glutathione and glutathione-S-transferase (GST) activity was observed in liver homogenate of the B(a)P-exposed animals. Residues of B(a)P were detected in liver tissue with a concentration parallel to the B(a)P dose level. In conclusion, B(a)P caused abnormal changes in the hemogram, evidence of tumor formation through B(a)P-induced oxidative stress, and it was accumulated in the liver tissue of mice. 相似文献
998.
Three endocrine disrupting chemicals (EDCs), triclosan (TCS), 4-n-nonylphenol (4-n-NP), and di-n-butyl phthalate (DBP) were determined using stir bar sorptive extraction (SBSE) along with high-performance liquid chromatography/photodiode array detection (HPLC/DAD). Benzyl butyl phthalate was used as an internal standard. The targeted analytes could be rapidly determined with limits of quantification (LOQ) ranging from 4.1 (DBP), 10 (TCS), to 34 (4-n-NP)?µg?L?1 in real samples such as bottled waters, personal care products, soaps, lotions, and urine. The results show that the developed analytical scheme is solvent-saving, efficient, and capable of fast screening samples for these common EDCs. 相似文献
999.
The present investigation was aimed to determine the effect of chronic exposure of carbendazim on cellular changes in testes of male goats. The goats were randomly divided into two groups, control and treatment (N?=?7 each). The treatment group was exposed to carbendazim at the dose rate of 50?mg?kg?1 body weight per day orally, once daily for 180 consecutive days. Testes were removed from control and experimental animals surgically on the 90th, 120th, and 180th day. On the 180th day of the treatment, a maximum number of seminiferous tubules became atrophic, and vacuolization of germinal epithelium, and sloughing of the germinal epithelium and sertoli cells was more marked as compared to days 90 and 120. Some of the seminiferous tubules were devoid of germinal cells. These pathological findings were supported by ultrathin and electron microscopic examination. On the basis of the present investigation it could be concluded that chronic exposure of carbendazim in male goats did not allow proper maturation of testis. 相似文献
1000.
In this study, we investigated the effects of Matricaria chamomilla L. extract (MCE) on lipid peroxidation, antioxidant enzyme systems, and several liver enzymes in carbon tetrachloride (CCl4)-treated rats. Rats were divided into five groups. The first group (control group) was fed on standard feed. The rats in the other groups (CCl4, MCE50, MCE100, and MCE200) were injected intraperitoneally with 0.8?mL?kg?1 CCl4. Moreover, rats in the MCE50, MCE100, and MCE200 groups were gavaged with 50?mg?kg?1, 100?mg?kg?1, and 200?mg?kg?1 MCE, respectively. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, whole blood malondialdehyde (MDA) and glutathione (GSH) levels, and erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity levels were measured after 14 days of exposure. ALT and AST in the CCl4 group increased significantly in comparison to the control group (p?0.001). MCE decreased MDA levels and increased GSH, SOD, and GPx activities. Decreases were observed in CAT activity levels in the CCl4, MCE50, MCE100, and MCE200 groups at different significance levels. In conclusion, the findings suggest that, depending on the dose administered, MCE decreases CCl4-induced damage and consequent oxidative stress in rats; it affects the antioxidant system positively. 相似文献