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1.
A new cytotoxic thiodepsipeptide, verrucosamide (1), was isolated along with the known, related cyclic peptide thiocoraline, from the extract of a marine-derived actinomycete, a Verrucosispora sp., our strain CNX-026. The new peptide, which is composed of two rare seven-membered 1,4-thiazepane rings, was elucidated by a combination of spectral methods and the absolute configuration was determined by a single X-ray diffraction study. Verrucosamide (1) showed moderate cytotoxicity and selectivity in the NCI 60 cell line bioassay. The most susceptible cell lines were MDA-MB-468 breast carcinoma with an LD50 of 1.26 µM, and COLO 205 colon adenocarcinoma with an LD50 of 1.4 µM. Also isolated along with verrucosamide were three small 3-hydroxy(alkoxy)-quinaldic acid derivatives that appear to be products of the same biosynthetic pathway.  相似文献   
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The effects of crude extracts and an isolated compound from the leaves of milkweed, Pergularia daemia (Forssk) Choiv., on the antifeedant activity against two important lepidopteran pests, Helicoverpa armigera (Hub.) and Spodoptera litura (F.), were studied. Maximum antifeedant activity was recorded in ethyl acetate crude extract against H. armigera (70.3%) and S. litura (71.82%) at 1% concentration. Ethyl acetate crude extract was further subjected to column chromatography, which was performed using hexane as initial solvent and then by increasing the polar strength using ethyl acetate. Fractions collected at hexane and ethyl acetate (80:20) yielded 6-(4,7-hydroxy-heptyl) quinone, a novel compound which showed significant antifeedant activity against H. armigera (80.22% at 2000 ppm) and S. litura (68.31% at 2000 ppm).  相似文献   
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The aim of present study was to explore and document medicinal plants used for the traditional dermatological healthcare management practices by the the Tharu tribal community of Uttar Pradesh. The study was conducted during 2000–2004. Information was gathered from 230 informants residing in 46 villages in Terai region of Indo-Nepal boarder using questionnaires; oral interviews and group discussions. Total 92 medicinal plant species were cited for the preparation of 113 crude drug formulations. Voucher specimens of cited plant species were collected and identified as belonging to 82 genera and 49 families. Thirty-nine medicinal plant species were reported for the first time for dermatological healthcare problems from India. The dermatological healthcare problems managed were cut and wounds, ringworm, leprosy, eczema, scabies, leucoderma, boils, carbuncles, pimples, skin blemishes, spots, eruption, and burns etc. The most commonly and popularly used medicinal plant species for management of dermatological healthcare problems in the study area were Curcuma longa L., Azadirachta indica A. Juss and Melia azedarach L. It is concluded that dermatological healthcare management practice in the study area depends largely on wildly growing medicinal plant species. There is an urgent need to properly conserve the medicinal plant species growing in this area for human welfare. There is also need for further phytopharmacological studies to provide scientific explanation for the usages of 57 medicinal plant species for which to the best of our knowledge phytopharmacological literatures are not available.  相似文献   
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Combined effects of beta-glucan and lipopolysaccharide (LPS) on survival and immune response were studied in Cyprinus carpio that were challenged with the pathogen Aeromonas hydrophila. beta-Glucan from Saccharomyces cervisiae and LPS from a virulent strain of A. hydrophila were used in this study. Different concentrations of beta-glucan+LPS mixture were administered on days 1, 7, and 14 through different routes (intraperitoneal injection, bathing, and oral administration). Control and test fish were challenged by intraperitoneal injection of LD50 concentration of A. hydrophila on day 16 and subsequently, mortality and relative percent survival (RPS) were recorded. Intraperitoneal injection elicited 100% RPS even at the lowest concentration (100 microg beta-glucan+10 microg LPS); whereas, oral administration improved RPS rate of carps at higher concentration (1% beta-glucan+0.25% LPS). Bathing did not improve the RPS. Test animals injected with even the minimum dose of the immunomodulators (100 microg beta-glucan+10 microg LPS/fish) had a significant increase in total blood leukocyte counts and an increase in the proportion of neutrophils and monocytes. Superoxide anion production by macrophages was also elevated, which presumably aided the efficient killing of bacterial pathogen. Lower concentration of beta-glucan+LPS had an adjuvant effect on antibody production as pretreatment by injection of 100 microg beta-glucan+10 microg LPS/fish resulted in higher antibody titer against A. hydrophila following vaccination. RT-PCR analyses showed that the expression of interleukin-1beta mRNA did not increase in test fish when compared with the control. Classical and alternative complement pathways were not affected by either the dose or the route of administration of the compounds. It may be concluded that intraperitoneal injection and oral administration, and not the bathing, of beta-glucan+LPS mixture in carp could enhance resistance to challenge by A. hydrophila through changes in several non-specific and specific immune responses.  相似文献   
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Purpose  

The aim of the present investigation was to document the phytotherapeutic knowledge and veterinary healthcare management practices among the Tharu tribal community of Uttar Pradesh, India and to determine the consensus of such practices, in order to evaluate the potential for new veterinary drugs of herbal origin.  相似文献   
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In chickens, thymic CD4(+)CD25(+) cells are characterized as regulatory T cells. The objectives of this experiment were to study the effects of an in vivo lipopolysaccharide (LPS) injection on the percentage of CD4(+)CD25(+) cells in peripheral organs and the suppressive properties of splenic CD4(+)CD25(+) cells in chickens. Chickens were injected with LPS and CD4(+)CD25(+) cells were analyzed at 1, 2, 3, 5, and 10 d post LPS injection. The LPS injection increased CD4(+)CD25(+) cell percentage approximately 5-fold in the blood at 1 d post LPS injection (P < 0.001), 3-fold in the thymus at 3 d post LPS injection (P = 0.001), and 2.5-fold in the spleen at 2 d post LPS injection (P = 0.001) compared with the no-LPS-injected group. The LPS injection did not alter the CD4(+)CD25(+) cell percentage in the cecal tonsil (P = 0.162), lung (P = 0.098), or bone marrow (P = 0.071) at any time point measured. At 2 d post LPS injection, splenic CD4(+)CD25(+) cells lost their suppressive ability (P < 0.001). At 5 d post LPS injection, splenic CD4(+)CD25(+) cells not only regained their suppressive ability, but also became supersuppressive (P < 0.001). Splenic CD4(+)CD25(+) cells at 5 d post LPS injection produced 5.5-fold more (P = 0.005) IL-10 mRNA than splenic CD4(+)CD25(+) cells at 0 and 2 d post LPS injection. In conclusion, chicken regulatory T cells are differentially activated to facilitate immune response during the early stage of inflammation and to facilitate immune suppression at a later stage of inflammation.  相似文献   
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Silage, which is anaerobically fermented green fodder, is valued throughout the world as a source of animal feed during lean months. Several farms in India use carbohydrate sources like jaggery or molasses at 2% for preparation of silage, and this increases cost of production. The present study was undertaken to assess the effect of jaggery on quality and intake of maize silage, with an objective to find out whether additional carbohydrate source is essential in preparation of silage using green maize. Three silage types, one without jaggery (A), the second with 1% jaggery (B), and the third with 2% jaggery (C) were prepared in cylindrical bins under similar conditions. They were compared for colour, pH, lactic acid bacteria count, lactic acid content, proximate composition and silage intake by sheep. Silage type C with 2% jaggery was significantly different from the other two types with values of 3.98 and 805.66 g for pH and mean silage intake, respectively. Even though the values of pH and dry matter intake for all three silage types were within normal levels, silage type C was significantly superior in terms of fermentation and palatability. The method of preparation followed could be ideal for small holder farmers requiring less quantity of silage.  相似文献   
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