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排序方式: 共有150条查询结果,搜索用时 15 毫秒
61.
Sheyla Mirabal Maria Regueiro Alicia M Cadenas L Luca Cavalli-Sforza Peter A Underhill Dmitry A Verbenko Svetlana A Limborska Rene J Herrera 《European journal of human genetics : EJHG》2009,17(10):1260-1273
Populations of northeastern Europe and the Uralic mountain range are found in close geographic proximity, but they have been subject to different demographic histories. The current study attempts to better understand the genetic paternal relationships of ethnic groups residing in these regions. We have performed high-resolution haplotyping of 236 Y-chromosomes from populations in northwestern Russia and the Uralic mountains, and compared them to relevant previously published data. Haplotype variation and age estimation analyses using 15 Y-STR loci were conducted for samples within the N1b, N1c1 and R1a1 single-nucleotide polymorphism backgrounds. Our results suggest that although most genetic relationships throughout Eurasia are dependent on geographic proximity, members of the Uralic and Slavic linguistic families and subfamilies, yield significant correlations at both levels of comparison making it difficult to denote either linguistics or geographic proximity as the basis for their genetic substrata. Expansion times for haplogroup R1a1 date approximately to 18 000 YBP, and age estimates along with Network topology of populations found at opposite poles of its range (Eastern Europe and South Asia) indicate that two separate haplotypic foci exist within this haplogroup. Data based on haplogroup N1b challenge earlier findings and suggest that the mutation may have occurred in the Uralic range rather than in Siberia and much earlier than has been proposed (12.9±4.1 instead of 5.2±2.7 kya). In addition, age and variance estimates for haplogroup N1c1 suggest that populations from the western Urals may have been genetically influenced by a dispersal from northeastern Europe (eg, eastern Slavs) rather than the converse. 相似文献
62.
Irene Esteban‐Cornejo Pontus Henriksson Cristina Cadenas‐Sanchez Jérémy Vanhelst Maria Forsner Frederic Gottrand Mathilde Kersting Luis A. Moreno Jonatan R. Ruiz Kurt Widhalm Francisco B. Ortega 《Maternal & child nutrition》2018,14(1)
The study aims to examine the individual and combined association of early life factors (birth weight, birth length, and any and exclusive breastfeeding) with attention capacity in adolescents. The study included 421 European adolescents (243 girls), aged 12.5–17.5 years, who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence Study. Body weight and length at birth of adolescents were collected from parental records. The duration of any and exclusive breastfeeding were self‐reported. The d2 Test of Attention was administered to assess attention capacity. The main results showed that birth weight, birth length, breastfeeding, and exclusive breastfeeding were related to attention capacity in boys (β ranging from 0.144 to 0.196; all p < .05) after adjustment for age, centre, gestational age, maternal education, family affluence scale, and body mass index. Among boys, differences in attention capacity were found according to tertiles of birth weight and birth length (p < .05), as well as borderline significant differences across groups of any and exclusive breastfeeding (p = 0.055 and p = 0.108, respectively) after adjusting for potential confounders. In addition, boys with 3 early life risk factors (low birth weight, low birth length, and <3 months of breastfeeding) had significantly lower scores in attention capacity compared with boys with 0 risk factors (percentile score ? 15.88; p = 0.009). In conclusion, early life factors, both separately and combined, may influence attention capacity in male European adolescents. Importantly, the combination of the 3 early life risk factors, low birth weight, low birth length, and <3 months of breastfeeding, even in normal ranges, may provide the highest reduction in attention capacity. 相似文献
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65.
Juan Iovanna Nelson Dusetti Belen Cadenas Daniel P. Cardinali 《Journal of pineal research》1990,9(1):51-63
The synthesis of the cytoskeletal protein actin exhibits, in the rat hypothalamus, a diurnal variation with maxima during morning hours. The objective of the present study was to assess whether melatonin injection could affect the in vitro incorporation of 35S-methionine into actin, as well as the levels of actin mRNA, in the hypothalamus of adult male rats treated either acutely or chronically with the hormone at 10:00 or 18:00. Injection of 100 micrograms/kg of melatonin for ten days at either time induced a significant depression in the incorporation of 35S-methionine into a 43 kDa protein with the electrophoretic mobility of actin. The specific activity of total soluble proteins after labeled methionine incubations decreased only after evening melatonin administration (100 micrograms/kg, ten days). Hypothalamic actin mRNA levels, quantitated by dot-blot analysis, decreased only after the injection of 100 micrograms/kg melatonin for ten days at 10:00. Neither a 10-micrograms/kg dose of melatonin, nor a single injection of 100 micrograms/kg melatonin, caused any significant change in the parameters examined. Melatonin (100 micrograms/kg for ten days) did not modify hypothalamic somatostatin or H-Ras mRNA concentration. These results suggest the existence of an inhibitory effect of melatonin on hypothalamic actin synthesis. 相似文献
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Mitochondrial nitric oxide synthase 总被引:6,自引:0,他引:6
Mitochondria produce nitric oxide (NO) through a Ca(2+)-sensitive mitochondrial NO synthase (mtNOS). The NO produced by mtNOS regulates mitochondrial oxygen consumption and transmembrane potential via a reversible reaction with cytochrome c oxidase. The reaction of this NO with superoxide anion yields peroxynitrite, which irreversibly modifies susceptible targets within mitochondria and induces oxidative and/or nitrative stress. In this article, we review the current understanding of the roles of mtNOS as a crucial biochemical regulator of mitochondrial functions and attempt to reconcile apparent discrepancies in the literature on mtNOS. 相似文献
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69.
Cristina Cadenas 《Archives of toxicology》2015,89(12):2471-2472
70.
Azcarate-Peril MA Foster DM Cadenas MB Stone MR Jacobi SK Stauffer SH Pease A Gookin JL 《Gut microbes》2011,2(4):234-243
Investigation of bacteria involved in pathogenesis of necrotizing enterocolitis (NEC) is limited by infant fragility, analysis restricted to feces, use of culture-based methods, and lack of clinically-relevant animal models. This study used a unique preterm piglet model to characterize spontaneous differences in microbiome composition of NEC-predisposed regions of gut. Preterm piglets (n=23) were cesarean-delivered and nurtured for 30 hours over which time 52% developed NEC. Bacterial DNA from ileal content, ileal mucosa, and colonic mucosa were PCR amplified, subjected to terminal restriction fragment length polymorphism (TRFLP) analysis and targeted 16S rDNA qPCR. Preterm ileal mucosa was specifically bereft in diversity of bacteria compared to ileal content and colonic mucosa. Preterm ileum was restricted to representation by only Proteobacteria, Firmicutes, Cyanobacteria and Chloroflexi. In piglets with NEC, ileal mucosa was uniquely characterized by increases in number of Firmicutes and diversity of phyla to include Actinobacteria and uncultured bacteria. Five specific TRFLP profiles, corresponding in closest identity to Clostridium butyricum, C. neonatale, C. proteolyticum, Streptomyces spp., and Leptolyngbya spp., were significantly more prevalent or observed only among samples from piglets with NEC. Total numbers of Clostridium spp. and C. butyricum were significantly greater in samples of NEC ileal mucosa but not ileal content or colonic mucosa. These results provide strong support for ileal mucosa as a focus for investigation of specific dysbiosis associated with NEC and suggest a significant role for Clostridium spp., and members of the Actinobacteria and Cyanobacteria in the pathogenesis of NEC in preterm piglets. 相似文献