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41.
There is high current interest in the chemopreventive potential of Brassica vegetables (cruciferae), particularly due to their content in glucosinolates (GL), which upon myrosinase hydrolysis release the corresponding isythiocyanates (ITC). Some ITCs, such as sulforaphane (SFN) from broccoli ( Brassica oleacea italica), have been found to possess anticancer activity through induction of apoptosis in selected cell lines, as well as indirect antioxidant activity through induction of phase II detoxifying enzymes. Japanese daikon ( Raphanus sativus L.) is possibly the vegetable with the highest per capita consumption within the Brassicaceae family. Thanks to a recently improved gram scale production process, it was possible to prepare sufficient amounts of the GL glucoraphasatin (GRH) as well as the corresponding ITC 4-methylthio-3-butenyl isothiocyanate (GRH-ITC) from its sprouts. This paper reports a study on the cytotoxic and apoptotic activities of GRH-ITC compared with the oxidized counterpart 4-methylsulfinyl-3-butenyl isothiocyanate (GRE-ITC) on three human colon carcinoma cell lines (LoVo, HCT-116, and HT-29) together with a detailed kinetic investigation of the direct antioxidant/radical scavenging ability of GRH and GRH-ITC. Both GRH-ITC and GRE-ITC reduced cell proliferation in a dose-dependent manner and induced apoptosis in the three cancer cell lines. The compounds significantly ( p < 0.05) increased Bax and decreased Bcl2 protein expression, as well as producing caspase-9 and PARP-1 cleavage after 3 days of exposure in the three cancer cell lines. GRH-ITC treatment was shown to have no toxicity with regard to normal human lymphocytes (-15 +/- 5%) in comparison with SFN (complete growth inhibition). GRH and GRH-ITC were able to quench the 2,2-diphenyl-1-picrylhydrazyl radical, with second-order rate constants of 14.0 +/- 2.8 and 43.1 +/- 9.5 M(-1) s(-1), respectively (at 298 K in methanol), whereas the corresponding value measured here for the reference antioxidant alpha-tocopherol was 425 +/- 40 M (-1) s (-1). GRH reacted with H2O2 and tert-butyl hydroperoxide in water (pH 7.4) at 37 degrees C, with rate constants of 1.9 +/- 0.3 x 10(-2) and 9.5 +/- 0.3 x 10(-4) M(-1) s (-1) (paralleling recently developed synthetic antioxidants) being quantitatively (>97%) converted to GRE. It is demonstrated that GRH-ITC has interesting antioxidant/radical scavenging properties, associated with a selective cytotoxic/apoptotic activity toward three human colon carcinoma cell lines, and very limited toxicity on normal human T-lymphocytes.  相似文献   
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Ecological niche models (ENMs) and species distribution models (SDMs) have been widely applied to various studies relevant to biogeography, conservation biology, and ecology. These modelling techniques seek to develop spatial maps for projecting, among others past, current, and future species distributions. Born in the field of terrestrial ecology, only in recent years have these models been applied to marine environmental issues, especially to improve the forecasting of the distribution of occurrences and capturing of fishery resources. This study aimed to present through bibliometric analysis the characteristics of articles related to the use of ENMs and SDMs in marine fishery resources considering three main points: (1) state of the art: number of articles over the years, journals, countries, collaborations, and focus of research; (2) characteristics linked to fishery resources: marine biogeographic realms, taxonomic groups, life phases, oceanographic zones, and behaviours; (3) characteristics linked to methods: type of method, type of biological and, environmental data. We provide a list of 378 articles (derived from 930 screened ones), the results, and a discussion of our findings, which represent a baseline for the current status (strengths, limits, and gaps) of the interface between ENMs/SDMs and fishery resources.  相似文献   
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This study provides information about nutrient composition of adult males of southern king crab (Lithodes santolla). Proximate composition of raw and cooked meat (g/100 g meat) averaged: moisture?=?80.9 and 78.6, protein?=?14.6 and 16.3, fat?=?0.70 and 0.76, and ash?=?2.03 and 2.10, respectively. Arginine, glutamic acid, leucine, and aspartic acid (20.4, 9.4, 8.0, and 7.9 g aa/100 g protein, respectively) were the major amino acids. The predominant fatty acid was 18:1n-9c (21.8 and 22.1%), followed by 20:5n-3 (17.1 and 21.8%), 16:0 (15.8 and 15.3%), and 22:6n-3 (11.0 and 13.5%). Cooked meat contained more cholesterol (51.0 mg/100 g meat) and phospholipids (60.1 mg/100 g meat) than raw meat (37.3 and 13.9 mg/100 g meat, respectively), with phosphatidylcholine representing over 80% of the total phospholipid content. The main tocopherol was α-tocopherol (raw meat?=?1.30 mg/100 g meat, cooked meat?=?1.14 mg/100 g meat). Major mineral contents of raw and cooked meat (mg/100 g meat) were: Na?=?509 and 594, K?=?179 and 203, Ca?=?114 and 197, P?=?126 and 143, Mg?=?34 and 41, Fe?=?1.26 and 1.86, and Zn?=?1.88 and 2.64, respectively. Thus, the nutritional quality of the cooked meat of the southern king crab makes it especially adequate for cholesterol-restricted, balanced low-fat meat diets.  相似文献   
44.
A 9-year-old neutered male domestic shorthair cat was presented because of coughing, dysphagia, and prostration. Examination revealed firm bilateral anterocervical swellings extensively adhered to the surrounding tissues. Anisocoria with left-side miosis was also evident. X-ray and ultrasound examinations along with a fine-needle aspiration biopsy were performed. Slides were stained with May-Grünwald Giemsa, and a diagnosis of salivary gland carcinoma was made. At surgery, the tumor was found to involve both submandibular salivary glands as well as adjacent lymph nodes and surrounding tissues. The cat was euthanized and necropsy was performed. The majority of tissues and organs examined histologically, including mandibular and retropharyngeal lymph nodes, soft palate, laryngopharynx and lungs, contained neoplastic cells whose appearance was consistent with adenocarcinoma. Bilateral salivary adenocarcinoma has not previously been reported in cats, and extensive metastases are rare.  相似文献   
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In recent years, bats have been found to harbour many viruses, raising several questions about their role as reservoirs and potential disseminators of zoonotic viruses. We investigated the presence of six virus families in bats in three regions of Central‐Southern Italy. Astroviruses were identified in seven of 13 bat species. Sequence analysis revealed marked genetic heterogeneity among the astroviruses identified, with nucleotide identity ranging between 60.26% and 87.62%. Astrovirus diversity was not associated with the bat species, the geographic areas or the bat colony, suggesting the circulation of several astrovirus strains in Italian ecosystems. Genetic diversification and interspecies transmission appear common in bat astroviruses and could provide, potentially, the bases for transmission to humans and other mammals. Yet overemphasizing this risk might have detrimental consequences for bat conservation and preservation of the important ecosystem services bats provide.  相似文献   
48.
beta-Sitosterol is a plant sterol that has received much attention because of its effectiveness in reducing the absorption of dietary cholesterol, as well as in offering protection from cardiovascular diseases and cancer development. Thus, the knowledge of the interaction of beta-sitosterol with biological membranes can help in understanding its mechanism of action. In the present paper, the differential scanning calorimetry technique has been used to study the interaction of beta-sitosterol with a biomembrane model constituted by dimyristoylphosphatidylcholine multilamellar vesicles. Furthermore, kinetic experiments have been carried out to follow the uptake of beta-sitosterol by biomembranes and the effect of beta-cyclodextrins on such a process. Our results indicate that opportune concentrations of beta-cyclodextrins improve the uptake of beta-sitosterol by phospholipid membranes.  相似文献   
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