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81.
Organochlorine pesticide residues were determined in 10 species of fishes caught at Cochin and Rameshwaram coast, and sold in Coimbatore, Tamil Nadu, India. Species were selected on the basis of their regular availability throughout the year and commercial value. A total of 389 fishes were analyzed for organochlorine residues and their suitability for human consumption was evaluated. Results show varying levels of residues of hexachlorocyclohexane (HCH), DDT, heptachlor epoxide, endosulfan and dieldrin. Among the 10 species, high concentration of pesticide residues were recorded in Sardinella longiceps, Carangoides malabaricus, Chlorophthalmus agassizi, Saurida tumbil and Rastrelliger kanagurta. The variation in total organochlorine residues among species and between places was not significant (P>0.05). Only five species of fishes showed monthly variation in residue levels and there was no significant correlation between the body size and residue levels in the tissue. About 22% of the fishes exceeded the maximum residue limits (MRL) of total HCH prescribed by FAO/WHO for fish products. The calculated dietary intake of total HCH through consumption of C. malabaricus, C. agassizi and S. longiceps exceeded the maximum acceptable dietary intake (ADI) limits prescribed for human consumption. The present study recommends continuous monitoring of environmental contaminants in marine fishes to assess the possible impact on human health.  相似文献   
82.
Semecarpus anacardium Linn. of the family Anacardiaceae has many applications in the Ayurvedic and Siddha systems of medicine. We have tested the antitumour activity of Semecarpus anacardium nut extract against experimental mammary carcinoma in animals. As there is a direct relationship between the proliferation of tumour cells and the activities of the glycolytic and gluconeogenic enzymes, we studied changes in the activities of enzymes involved in this metabolic pathway in the liver and kidney. The enzymes investigated were glycolytic enzymes, namely hexokinase, phosphoglucoisomerase, aldolase and the gluconeogenic enzymes, namely glucose-6-phosphatase and fructose-1,6-biphosphatase in experimental rats. A significant rise in glycolytic enzyme activities and a simultaneous fall in gluconeogenic enzyme activities were found in mammary carcinoma bearing rats. Drug administration returned these enzyme activities to their respective control activities.  相似文献   
83.

Objectives

The urinary excretion of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) was used as a biomarker of oxidative DNA damage. The urinary 8-oxodG levels in petrol filling station attendants (exposed) at various petrol bunks were estimated as well as in the unexposed (cashier) population.

Materials and Methods

A total of 100 workers (79 petrol fillers and 21 cashiers) aged from 20 to 41 years participated in the study. An informed consent was taken from each participant. Information on personal habits and health was obtained through a questionnaire. After shifts, urine samples were collected analyzed for 8-oxodG using enzyme-linked immunosorbent assay (ELISA).

Results

Fifty-three percent of workers were in the 21–30 years age group. The maximum level of 8-oxodG was observed in the age group ≥ 41 years and the minimum in the age group of 31–40 years. The maximum level of 8-oxodG was observed among those workers who had ≥ 21 years of experience. The concentrations of 8-oxodG were significantly higher in petrol fillers than those in cashiers (p < 0.05).

Conclusions

Despite the conflicting results obtained in our study it was shown that 8-oxodG is related to chemical exposure. Further research is needed embracing a bigger number of participants to highlight the correlations between the exposure and the effects.  相似文献   
84.
Etoposide and nanoparticle formulations were labeled with Tc-99m and their biodistribution and pharmacokinetics were studied after intravenous administration in healthy mice and rabbits respectively. Etoposide was rapidly cleared from the body, while the disposition of nanoparticles was slower. A higher proportion of nanoparticles compared with etoposide was observed in different organs of mice. Scintigraphic images of rabbits concluded that the radioactivity shown by formulations is significantly higher after 4 and 24 h, as compared with etoposide administered in rabbits. AUC0 ? ∞, clearance and MRT are better than those obtained with etoposide administration. The overall high residence of nanoparticles, compared with etoposide, signifies the advantage of PLGA and PCL nanoparticles as drug carriers for etoposide in enhancing the bioavailability and reducing the etoposide-associated toxicity.  相似文献   
85.
BackgroundCisplatin (a platinum-compound) is a anti-neoplastic drug used in the treatment of various cancers but eventually results in severe adverse effects namely nephrotoxicity or renal disorder through generation of reactive oxygen species (ROS). This biochemical measurements and histopathology analysis investigated a possible protective effect of 1,2-diazole with regards to cisplatin-induced nephrotoxicity in experimental animals.MethodsAnimals were divided into four groups of six mice each. Group A: normal control, vehicle (1 % (w/v) gum acacia in phosphate buffer saline (PBS)). Group B: cisplatin group, vehicle + cisplatin (7.5 mg/kg). Group C: 1,2-diazole (10 mg/kg) + cisplatin and Group D: silymarin (50 mg/kg) + cisplatin. Each vehicle/drug treatment was given daily via intraperitoneal (ip) injection for 10 consecutive days starting from day 1. On group B, C and D cisplatin was given in single dose only on day 5 one hour post drug administration. Animals were allowed till 10th day and on day 11 all four groups animals were anesthetized. Blood samples were collected and serum was isolated for biochemical measurements. The rats were then euthanized by cervical dislocation and their kidney was recovered and then prepared for biochemical measurements and histopathology analyses.ResultsPretreatment with 1,2-diazole prevented nephrotoxicity induced by cisplatin through a protective mechanism that involved reduction of increased oxidative stress by significantly increasing the enzymatic and non enzymatic antioxidant enzymes such as glutathione peroxidase (GPx), glutathione (GSH) and diminishing the lipid peroxidation (LPO). The pretreatment with 1,2-diazole does not affect superoxide dismutase (SOD), catalase (CAT), serum urea and creatinine level during nephrotoxicity when compared to cisplatin-induced group. Moreover, the 1,2-diazole animals shown significant decrease in urine volume and kidney weight when compared with cisplatin-induced group. Histopathological findings reveals the protective efficacy of 1,2-diazole that restores histopathological changes against nephrotoxicity.ConclusionThese analysis will provide a critical evidence that 1,2-diazole could provide a new protective strategy against cisplatin-induced nephrotoxicity.  相似文献   
86.
Fetal alcohol syndrome (FAS), a condition occurring in some children of mothers who have consumed alcohol during pregnancy, is characterized by craniofacial malformations, and physical and mental retardation. It is significant that even children with history of gestational ethanol exposure but relatively unaffected overall IQ performance, often exhibit learning difficulties and behavioral problems, suggestive of impaired memory formation. Hence, the specific aim of this study was to examine memory formation in chicks exposed to ethanol during early gestation toward the understanding of neurobehavioral disturbances in FAS. Chicks were exposed to alcohol on gestational days 1-3 by injection of ethanol into the airspace of freshly fertilized eggs. The effects of prenatal ethanol on physical growth and development, and memory formation were studied. The one-trial passive avoidance learning paradigm in 1-day-old chicks was used to study memory formation in these chicks. It was observed that chick embryos exposed to 10% ethanol on gestational days 1-3 had significant reduction in all body parameters when compared with appropriate controls. Further, ethanol-exposed chick embryos had significantly impaired (P<.05) long-term memory (LTM) formation after training, though short-term or intermediate-term memory formation was unimpaired. Thus, the findings of the current study demonstrate the detrimental effects of ethanol exposure during early pregnancy on developing chick embryos in general and on memory formation in particular. Hence, it is suggested that impairment in LTM could be a fundamental mechanism for learning disorders and neurobehavioral abnormalities observed in FAS.  相似文献   
87.
The effect of curcumin on ethanol induced liver toxicity was evaluated. The increased levels of aspartate transaminase and alkaline phosphatase induced by ethanol were significantly lowered by curcumin. Elevated serum cholesterol, phospholipids and free fatty acids were observed in ethanol fed rats, but on curcumin treatment they decreased. We have also observed a marked decrease in the levels of thiobarbituric acid reactive substances in serum of alcoholic rats fed curcumin. Thus this study shows that curcumin offers protection against ethanol induced toxicity. © 1998 John Wiley & Sons, Ltd.  相似文献   
88.
This article presents the status of food security versus nutrition security in India. Food security is defined as the availability and the access of food to all people; whereas nutrition security demands the intake of a wide range of foods which provides the essential needed nutrients. It is estimated that the average dietary intake in India is 2280 calories. In 9 major states, the average was less than 2400 calories, suggesting poverty. In a 1988-90 survey, only 10% of the children, and about 50% of the adults, were considered to have a normal nutritional status. The rest suffered from different levels of Chronic Energy Deficiency. In addition, contradictions have also developed within policies in India that seek to address these issues. Recognizing that agriculture is the key to poverty eradication, India recently drafted the Agriculture Policy. The Policy focuses on rain-fed farming, unemployment, and malnutrition in rural areas, revitalizing the cooperatives, and increasing the involvement of nongovernmental organizations. However, there are certain issues of concern in the Policy with the most damaging aspect seen in the promotion of existing inequalities in the rural sector.  相似文献   
89.
Li Y  Reddy K  Reid SM  Cox WJ  Brown IH  Britton P  Nair V  Iqbal M 《Vaccine》2011,29(46):8257-8266
A major challenge for poultry vaccination is the design of vaccines that protect against multiple pathogens via a single protective dose delivered through mass vaccination methods. In this investigation, we examined herpesvirus of turkeys (HVT) as a vaccine vector for delivery of haemagglutinin (HA) antigen of highly pathogenic H7N1 avian influenza virus that can act as a dual vaccine against avian influenza and Marek's disease. The HVT vector was developed using reverse genetics based on an infectious bacterial artificial chromosome (BAC) clone of HVT. The BAC carrying the HVT genome was genetically modified to express the HA gene of a highly pathogenic H7N1 virus. The resultant recombinant BAC construct containing the modified HVT sequence was transfected into chicken embryo fibroblast (CEF) cells, and HVT recombinants (rHVT-H7HA) harbouring the H7N1 HA were recovered. Analysis of cultured CEF cells infected with the rHVT-H7HA showed that HA was expressed and that the rescued rHVT-H7HA stocks were stable during several in vitro passages with no difference in growth kinetics compared with the parent HVT. Immunisation of one-day-old chicks with rHVT-H7HA induced H7-specific antibodies and protected chickens challenged with homologous H7N1 virus against virus shedding, clinical disease and death. This vaccine supports differentiation between infected and vaccinated animals (DIVA) vaccination strategies because no nucleoprotein-(NP) specific antibodies were detected in the rHVT-H7HA vaccinated birds. The rHVT-H7HA not only provided protection against a lethal challenge with highly pathogenic H7N1 virus but also against highly virulent Marek's disease virus and can be used as a DIVA vaccine.  相似文献   
90.
A novel method for simultaneously detecting clonality by FISH, and presence of telomerase activity (telo+ cells) or histone H3 mRNA (H3+) in single cells from a mixed leukemic population is reported. The methods were validated using K562 cells mixed with peripheral blood granulocytes and bone marrow aspirate cells from newly diagnosed AML patients. Fifty patients with AML were analyzed for telo+ cells, while eight AML patients were analyzed for FISH-Telomerase and FISH-H3+ during remission induction therapy. Our results demonstrate that: (1). changes in the leukemic populations during therapy could be followed; (2). a favorable response to chemotherapy occurred when there was a reduction in both the cytogenetically abnormal cells along with reduction in telo+ cells within this abnormal population; (3). reduction of either telo+ cells or FISH+ cells alone did not correlate with good response. H3+ could be detected in only 4% of the leukemic population, most of which were cytogenetically abnormal. These newly established methods allow sub-populations of cells to be followed during disease progression and treatment and to elucidate factors that give a specific clone proliferative advantage.  相似文献   
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