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BACKGROUND: Altered serotonergic function is thought to play a role in the pathophysiology of major depressive episodes based upon evidence from neuroimaging, pharmacological, postmortem and genetic studies. It remains unclear, however, whether depressed samples that differ with respect to having shown a unipolar versus a bipolar illness course also would show distinct patterns of abnormalities within the serotonergic system. The current study compared serotonin transporter (5-HTT) binding between unipolar-depressives (MDD), bipolar-depressives (BD) and healthy-controls (HC) to assess whether the abnormalities in 5-HTT binding recently found in depressed subjects with BD extend to depressed subjects with MDD. METHODS: The 5-HTT binding-potential (BP) measured using positron emission tomography (PET) and [(11)C]DASB was compared between unmedicated, depressed subjects with MDD (n = 18) or BD (n = 18) and HC (n = 34). RESULTS: Relative to the healthy group both MDD and BD groups showed significantly increased 5-HTT BP in the thalamus (24%, 14%, respectively), insula (15%) and striatum (12%). The unipolar-depressives had elevated 5-HTT BP relative to both BD and HC groups in the vicinity of the periaqueductal gray (PAG, 20%, 22%, respectively). The bipolar-depressives had reduced 5-HTT BP relative to both HC and MDD groups in the vicinity of the pontine raphe nuclei. Depression-severity correlated negatively with 5-HTT BP in the thalamus in MDD-subjects. CONCLUSIONS: The depressed phases of MDD and BD both were associated with elevated 5-HTT binding in the insula, thalamus and striatum, but showed distinct abnormalities in the brainstem. The latter findings conceivably could underlie differences in the patterns of illness symptoms and pharmacological sensitivity observed between MDD and BD.  相似文献   
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Textile dyes are becoming a growing threat to the environment. This report presents the findings of the study on the toxicity of the textile dye Alizarin Red S on two freshwater microalgae. The acute toxicity assay revealed that 96-h EC50 values of Chlorella vulgaris and Spirulina platensis were 29.81 mg/L and 18.94 mg/L respectively. The pigments chlorophyll-a, b and carotenoids in C. vulgaris on 96-h exposure to the dye were 2.91, 3.29 and 3.01 times lower in analogy to control whereas Spirulina platensis showed 2.89and 2.56 fold decrease in chlorophyll-a and carotenoid content than control. After the test period of 96-h with dye, the protein content of C. vulgaris and S. platensis were 2.33 and 1.77 times lower compared to the control. The growth inhibition rate, pigment as well as the protein content declined in compliance with the rise in dye concentration, which anticipate paradigm about the toxic effects of the textile dye.

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Bulletin of Environmental Contamination and Toxicology - This study shows the effect of soil type and temperature on the adsorption and desorption behaviour of pendimethalin using a batch...  相似文献   
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An inherent problem in electricity generation is that much of the heat produced cannot be converted into electricity and is dissipated in nearby heat sinks, such as lakes, rivers and oceans. In India, such heat rejection to water bodies is governed by legislation from ministry of environment and forests and central and state pollution control boards. New standards for thermal discharge issued by MoE&F in 1998 seem to be very stringent. But in the absence of relevant data for Indian sites appear to be somewhat justified. In order to make a realistic assessment of the impact of thermal discharge on aquatic ecosystems, the Department of Atomic Energy initiated the first major thermal ecological study in the country at two of its operating nuclear power plants, one at a coastal site in Kalpakkam and the other on the banks of river Kali at Kaiga. The 5 years duration co-ordinated research project involved researchers from eight different universities and national laboratories and experts from NIO, NIOT, CECRI, BARC, NPCIL and MoE&F. In view of the fact that the most of the forthcoming nuclear power plants in the country are coastally located, this article discusses the findings of Thermal Ecological Study at Kalpakkam. A major achievement of the study was to map the precise boundaries of the small mixing zone, the region of confluence of the heated water with the recipient water body, wherein the thermal plume effected a ∆T of only 3–5 °C due to rapid inundation and mixing with turbulent sea water. This caused a limited impact on the growth and distribution of the relatively sedentary benthic flora and fauna, though none of the motile forms, including fishes, were affected. Beyond the mixing zone, the life appeared to be as near normal as possible. No change in any physico-chemical parameter was noticed, except for a small expected decrease in dissolved oxygen at the discharge point. At Kalpakkam, position of the mixing zone shifts periodically due to formation of a natural sand bar by sea currents. This allows restoration of parameters, especially temperature to more conducive values and results in recolonization of the previously impacted sites. An ecologically encouraging finding of the study was that the impact was restricted in space and reversible in time. The data generated are expected to aid regulatory agencies in formulation of more appropriate stipulations for thermal discharge and also guide power industry to design eco-friendly technologies in future.

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Hypophysitis includes three histopathologically distinct entities – granulomatous, lymphocytic and xanthomatous forms. Etiopathogenesis and the immunological differences among these is not well characterized. This study aims to explore the immunopathogenesis of granulomatous and lymphocytic forms of hypophysitis. Demographic, clinical, endocrine function and radiological features of 33 histologically confirmed cases of hypophysitis were reviewed. Immunophenotyping of inflammatory component was performed in 13/33 cases. Visual disturbances (46%), headache (36%), polyuria/polydipsia (6%), menstrual disturbance (6%) and galactorrhoea (6%) were the frequent presenting symptoms. Endocrine abnormalities were noted in 11/18 cases evaluated (61%). Hypothyroidism was the most common endocrine abnormality (33.33%) followed by hyperprolactinaemia (22%) and hypocortisolism (16.66%). On neuroimaging, sellar mass with variable contrast enhancement was observed. On histology, granulomatous hypophysitis (GH) was more common (84.84%) than lymphocytic hypophysitis (LH) (15.15%). In GH, the infiltrate had almost equal proportions of CD3+ T cells and CD68+ histiocytes. Cytotoxic T cells (CD8+) predominated [CD4:CD8 < 1]. CD20+ B cell component ranged from <5% to 50%. Fibrosis, necrosis and giant cells accompanied GH. LH in contrast, had CD4+ T‐helper cell predominance [CD4: CD8 > 1]. CD68+ histiocytes constituted <20% and CD20+ B cells, 5–40% of the infiltrates. In conclusion, GH revealed cytotoxic T cell and histiocyte rich infiltrate in contrast to CD4+ T‐cell predominance in LH suggesting that the two forms have distinct immunological mechanisms in evolution, an autoimmune process in LH and type IV hypersensitivity response in GH.  相似文献   
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