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71.
Zieba DA Klocek B Williams GL Romanowicz K Boliglowa L Wozniak M 《Domestic animal endocrinology》2007,33(3):358-365
Recent observations in seasonal-breeding mammals indicate that the hypothalamus is programmed to become leptin resistant during long days (LD) and leptin sensitive during short days (SD). These observations support the possibility that photoperiod mediates at least part of its effects on melatonin secretion through changes in leptin sensitivity. Herein we examined the interaction of season and recombinant ovine leptin (oleptin) on melatonin secretion by pineal explants in short-term culture. Glands were collected after sunset from eight ewes during LD (March, April, May, June) and from an additional eight ewes during SD (September, October, November, December). Glands were transected saggitally and coronally into quarters, with each equilibrated in 2.5ml of DMEM for 120min, followed by a 3h incubation in medium containing either 0 or 50ng/ml of oleptin. Treatment with oleptin reduced (P<0.001) melatonin secretion compared to controls during LD by approximately 22% at 2, 2.5 and 3h of culture. However, in cultures from glands collected during SD, oleptin stimulated (P<0.078) melatonin secretion approximately 50% compared to control. These effects were consistent throughout each respective season. We conclude that the secretion of melatonin from the ovine pineal gland is negatively responsive to leptin during LD, whereas leptin may stimulate melatonin secretion during SD. 相似文献
72.
73.
Sylwester Czaplicki Dorota Ogrodowska Ryszard Zadernowski Iwona Konopka 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):198-204
An in vivo experiment was conducted to determine the effect of sea-buckthorn pulp oil feeding on the fatty acid composition of liver and adipose tissue of Wistar rats and the liver accumulation of retinol, its esters and α-tocopherol. For a period of 28 days, rats were given a modified casein diet (AIN-93) in which sea-buckthorn pulp oil, soybean oil and pork lard were used as sources of fat. Compared to the other fat sources, sea-buckthorn pulp oil was the most abundant in C16 fatty acids, carotenoids (mainly β-carotene) and tocopherols (mainly α-tocopherol). Its consumption was reflected in an increased share of palmitoleic acid in adipose tissue and the liver and an increased level of retinol in liver tissues (this was not observed for its esters). Although the type of fat did not have a significant effect on the average content of α-tocopherol in the liver, the variation of saturation of this tissue with α-tocopherol was the lowest when rats were fed a diet containing sea-buckthorn oil. This experiment indicates the possibility of affecting adipose tissue and liver by a diet. 相似文献
74.
Ten microsatellite loci were tested on Mendelian segregation in the bester – hybrid of beluga, Huso huso L. and sterlet, Acipenser ruthenus L. in the fourth generation. All studied loci showed disomic inheritance and Mendelian segregation of their alleles. The molecular approach by microsatellite DNA analysis represents a reliable tool for interspecific characterization of sturgeons and their hybrids (different alleles of several loci are present in sturgeon fishes, and interspecific hybrids posesses both maternal and paternal specific alleles). This is the first report of the Mendelian segregation testing in interspecific hybrid of acipenserid fishes using microsatellite DNA markers. 相似文献
75.
Chromosome preparations and assay of the microsatellite locus Afu‐68 were used to determine ploidy in Siberian sturgeon (Acipenser baeri Brandt) and F1 hybrids of Siberian sturgeon and Russian sturgeon (Acipenser gueldenstaedti Brandt). The chromosome number and microsatellite locus Afu‐68 were compared and these analyses were used for identification of ‘haploid’, ‘diploid’ and ‘triploid’ progeny of the studied cross of A. baeri× (A. baeri×A. gueldenstaedti). 相似文献
76.
Nicotiana wuttkei Clarkson and Symon discovered in the 1990s in Australia may be of potential interest to breeders as it carries resistance
to Peronospora hyoscyami de Bary. The crossability between N. wuttkei (2n = 4x = 32) and three N. tabacum (2n = 4x = 48) cultivars (‘Puławski 66’, ‘Wiślica’ and ‘TN 90’) and the morphology and cytology of their amphihaploid hybrids (2n = 4x = 40) were studied. Seeds were produced only when N. wuttkei was used as the maternal parent, but under normal germination all seedlings died. Viable F1 hybrids of N. wuttkei × N. tabacum cv. ‘Puławski’ and N. wuttkei × N. tabacum cv. ‘Wiślica’ were obtained only by in vitro cotyledon culture. The amphihaploid plants were intermediate between the parents
for most morphological traits. In 46.4% of the PMC’s, only univalents were present. The remainder of the cells had 1–5 bivalents
and 1–2 trivalents. In spite of a detectable frequency of monads (2.6%), dyads (2.6%) and triads (4.5%), the hybrids were
self and cross sterile. 相似文献
77.
78.
This study examines the role of urban regeneration policies in planning and governance within urban functional areas (UFAs) in Poland, in the context of the EU Cohesion Policy (CP). The empirical part of this study is based on comparing the approaches adopted in two Polish regions: Pomerania and Silesia. We describe the first successes but also the bottlenecks of the process, from negotiations and programming up to the implementation of the first tranche of integrated projects. We consider the factors that strengthen planning and governance within UFAs, while simultaneously influencing the local development, and territorial impacts of the EU Cohesion Policy in the given regions. This study is based on interviews with national, regional, and local actors. It defines the role of urban regeneration policies in shaping local socio-economic and spatial development in these regions and identifies the conditions required for the implementation of urban regeneration in functional areas. We also draw lessons for the future CP programming period from the experience of Polish regions, among the main beneficiaries of the EU Cohesion Policy. By evaluating the influence of Cohesion Policy at different government levels, our study may influence the discourse on its future, particularly in the context of strengthening the cooperation and multilevel governance. 相似文献
79.
Procyanidin oligomers from Japanese quince (Chaenomeles japonica) fruit inhibit activity of MMP-2 and MMP-9 metalloproteinases 总被引:1,自引:0,他引:1
Strek M Gorlach S Podsedek A Sosnowska D Koziolkiewicz M Hrabec Z Hrabec E 《Journal of agricultural and food chemistry》2007,55(16):6447-6452
The influence of procyanidin extract from Japanese quince fruit on the activities of matrix metalloproteinases MMP-2 and MMP-9 secreted to culture medium by human peripheral blood mononuclear cells (PBMC) and by human leukemia HL-60 cells was investigated by gelatin zymography. The extract proved to be an effective inhibitor of the enzymes activities (for MMP-2 and MMP-9 secreted by PBMC IC50 = 16-19 microg extract/mL and 22-25 microg extract/mL, respectively). To identify the most effective components of the extract it was fractionated by means of column chromatography on TSKgel Toyopearl HW-40 (S) bed. The obtained fractions were analyzed by TLC, HPLC, and MALDI-TOF MS. Their antioxidant activity was measured as cation radicals ABTS(.+) scavenging efficiency. The fractions VIII-XIV containing oligomers from trimer to hexamer (and probably higher oligomers) appeared to be the most effective inhibitors of MMP-2 and MMP-9 activity (IC50 value close to 4.6 microg total polyphenols/mL). To the best of our knowledge, it is the first report on gelatinase-inhibitory activity of Japanese quince fruit polyphenol extract. We conclude that polyphenols from Japanese quince can be used in cancer chemoprevention, although further studies are needed to elucidate the mechanisms underlying their biological activities. 相似文献
80.
Dorota Fopp‐Bayat 《Aquaculture Research》2008,39(16):1787-1792
Haploid gynogenesis was induced in Siberian sturgeon (Acipenser baeri Brandt) using UV‐irradiated bester (hybrid of Huso huso L. and Acipenser ruthenus L.) sperm. The inactivated heterologous sperm was used successfully to produce gynogenetic haploids of Siberian sturgeon. All haploid progeny were screened using microsatellite DNA analysis and uniparental transmission in gynogenetic haploids was confirmed. The objective of this study was to obtain haploids of Siberian sturgeon and describe the inheritance of microsatellite loci in haploid embryos of this species. This initial work, based on inheritance in haploid Siberian sturgeon, suggests that three studied microsatellite loci segregate disomically, three tetrasomically and one octasomically. 相似文献