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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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Type I interferons (IFN) are important mediators of the host defense against viral infections in mammals. In humans multiple subtypes of IFN-alpha exist, most of which possess antiviral activity. Little is known about the type I IFN genes in cats and the role they may play in feline immunological responses to viruses. We have isolated cDNAs encoding five feline IFN-alpha (feIFN) subtypes that share from 95 to 99% amino acid sequence identity. FeIFN-alpha5 has five additional amino acids inserted at position 139, which are not present in the other four subtypes. Sequence identity of the feIFN proteins encoded by the five clones compared to human IFN-alpha2 is approximately 60%. Unlike most of the human subtypes, each of the five feline IFN sequences has an N-glycosylation recognition site. Expression of all five feIFN-alpha subtypes in Chinese hamster ovary (CHO) cells was confirmed by Western blot analysis, and all resulting proteins were glycosylated. The antiviral activity of each feIFN-alpha subtype produced in transiently transfected CHO cell cultures was tested in vitro. In addition, subtype feIFN-alpha6 was expressed in the yeast, Pichia pastoris. The resulting secreted mature recombinant protein was purified and demonstrated significant antiviral activity and induction of 2',5'-oligoadenylate synthetase activity in vitro.  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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Radioactively labeled iron (59Fe) was used to study differential uptake in sorghum plants in the recovery stage of chlorosis. Radio-labeled 59Fe was supplied through root feeding in nutrient solution experiment (48 hrs, pH 6.2) to non-chlorotic and chlorotic plants. Chlorotic plants were further treated with foliar spray [ferrous sulfate (FeSO4), FeSO4 + thiourea (TU), FeSO4 + citric acid (CA), FeSO4 + thioglycollic acid (TGA)] to study the uptake of radio-labeled 59Fe through root feeding during recovery process of chlorosis. Under iron deficiency, the differential uptake of 59Fe was markedly increased in leaves and stem of chlorotic control (-Fe) sorghum plants as compared to non-chlorotic control (+Fe) and foliar sprayed (FeSO4, FeSO4 + TU, FeSO4 + CA, and FeSO4 + TGA) plants. The lowest uptake of 59Fe was observed in younger leaves (24.33 nmol, g?1 fresh weight h?1) and stem (1.98 nmol, g?1 fresh weight h?1) of non-chlorotic control followed by foliar sprayed plants in comparison to chlorotic control, respectively. Similarly less 59Fe uptake was observed in the older leaves of FeSO4 + CA sprayed (21.70 nmol, g?1 fresh weight h?1) plants in comparison to chlorotic control (35.60 nmol, g?1 fresh weight h?1). The highest differential 59Fe uptake through nutrient medium was in the roots of plants, which were foliar sprayed with FeSO4 along with TU. The role of iron alone and along with citric acid and thiol compounds is discussed in recovery of chlorosis.  相似文献   
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The physiology of NaCl induced stress was studied in two prop species, cowpea and 4 cultivars of tobacco one of which (Jayashree) is salt sensitive. It was found that the growth of all the cvs of tobacco was reduced by the presence of NaCl (100 mH) in the nutrient medium. While the fresh wt per unit area of the leaves of salt‐tolerant tobacco cv. I and PV‐7 (Nicotiana tabacum L.) and MPS‐219 (N. rustica L.) was increased’ significantly, it was decreased in the salt‐sensitive Jayashree. The dry wt per unit leaf area was decreased much more in I, PV‐7 and J than in NPS‐219. The total chlorophyll was reduced in all and more so in Jayashree.

The relative turgidity % was found to decrease in the primary leaves of cowpea (Vigna unguiculata L.) in the first 6 days of treatment with 100 mM NaCl in the nutrient medium while the decrease was less significant in the first and and second trifoliate leaves, showing that there was readjustment with growth of the plant to salinity. The 14C fixation in the leaf disks of cowpea grown in NaCl was much less than in the control plants. The studies reveal that there is a general reduction in the growth of both tobacco and cowpea following NaCl treatment and this effect is due to a decrease in the total chlorophyll and a reduced rate of photosynthesis.  相似文献   
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Two sorghum (Sorghum bicolor L. Moench) hybrids CSH‐10 and ‐ 11 and their parent cultivars 296‐A, SB‐1055 and MR‐715 were examined for their tolerance to Fe‐deficiency stress, and also Fe uptake. It was observed that there was greater reduction of pH of the nutrient media and more rapid recovery from chlorosis only in the female parent 296‐A, and to some degree in the hybrids, but not in the male parents. The results indicated that Fe uptake‐translocation were inversely related to their Fe stress tolerance.  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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