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81.
Both the extent and location of the maternal ancestral deme from which the Ashkenazi Jewry arose remain obscure. Here, using complete sequences of the maternally inherited mitochondrial DNA (mtDNA), we show that close to one-half of Ashkenazi Jews, estimated at 8,000,000 people, can be traced back to only 4 women carrying distinct mtDNAs that are virtually absent in other populations, with the important exception of low frequencies among non-Ashkenazi Jews. We conclude that four founding mtDNAs, likely of Near Eastern ancestry, underwent major expansion(s) in Europe within the past millennium.  相似文献   
82.
We investigated the changes in the hepatic proteome in murine models for toxic-induced fibrogenesis and sclerosing cholangitis. A comprehensive comparison of protein changes observed is made and the mechanistical basis of the expression changes is discussed. Hepatic fibrosis was induced by repetitive intraperitoneal CCl4 treatment of BALB/c mice or developed spontaneously in BALB/c-ATP-binding cassette, subfamily B, member 4 (Abcb4) knock out mice. Fibrosis was verified by a morphometric score and assessment of hydroxyproline content of liver tissue, respectively. The innovative difference in-gel electrophoresis (DIGE) technique was used to analyse protein expression levels of the mouse proteome. Results were confirmed by Western blotting and real-time RT-PCR. In CCl4-induced fibrosis 20 out of 40 and in BALB/c-Abcb4(-/-) mice 8 out of 28 differentially expressed proteins were identified utilizing DIGE. Only two proteins, selenium-binding protein (Sbp2) and carbonic anhydrase 3, have been unidirectionally expressed (i.e. down-regulated) in both models. Relevant differences in the pathogenesis of toxically induced liver fibrosis and sclerosing cholangitis exist. The only novel protein with regard to liver fibrosis depicting a unidirectional expression pattern in both animal models was Sbp2. An explicit protein function could not be clarified yet.  相似文献   
83.
Oxidative cell damage is involved in the pathogenesis of atherosclerosis, cancer, diabetes and other diseases. Uptake of fruit juice with especially high content of antioxidant flavonoids/polyphenols, might reduce oxidative cell damage. Therefore, an intervention study was performed with a red mixed berry juice [trolox equivalent antioxidative capacity (TEAC): 19.1 mmol/L trolox] and a corresponding polyphenol-depleted juice (polyphenols largely removed, TEAC 2.4 mmol/L trolox), serving as control. After a 3-week run-in period, 18 male probands daily consumed 700 mL juice, and 9 consumed control juice, in a 4-week intervention, followed by a 3-week wash-out. Samples were collected weekly to analyze DNA damage (comet assay), lipid peroxidation (plasma malondialdehyde: HPLC/fluorescence; urinary isoprostanes: GC-MS), blood glutathione (photometrically), DNA-binding activity of nuclear factor-kappaB (ELISA) and plasma carotenoid/alpha-tocopherol levels (HPLC-DAD). During intervention with the fruit juice, a decrease of oxidative DNA damage (p<5x10(-4)) and an increase of reduced glutathione (p<5x10(-4)) and of glutathione status (p<0.05) were observed, which returned to the run-in levels in the subsequent wash-out phase. The other biomarkers were not significantly modulated by the juice supplement. Intervention with the control juice did not result in reduction of oxidative damage. In conclusion, the fruit juice clearly reduces oxidative cell damage in healthy probands.  相似文献   
84.
We use eddy covariance measurements of net ecosystem productivity (NEP) from 21 FLUXNET sites (153 site-years of data) to investigate relationships between phenology and productivity (in terms of both NEP and gross ecosystem photosynthesis, GEP) in temperate and boreal forests. Results are used to evaluate the plausibility of four different conceptual models. Phenological indicators were derived from the eddy covariance time series, and from remote sensing and models. We examine spatial patterns (across sites) and temporal patterns (across years); an important conclusion is that it is likely that neither of these accurately represents how productivity will respond to future phenological shifts resulting from ongoing climate change. In spring and autumn, increased GEP resulting from an ‘extra’ day tends to be offset by concurrent, but smaller, increases in ecosystem respiration, and thus the effect on NEP is still positive. Spring productivity anomalies appear to have carry-over effects that translate to productivity anomalies in the following autumn, but it is not clear that these result directly from phenological anomalies. Finally, the productivity of evergreen needleleaf forests is less sensitive to phenology than is productivity of deciduous broadleaf forests. This has implications for how climate change may drive shifts in competition within mixed-species stands.  相似文献   
85.
86.
ARR22 (At3g04280) is a novel Type A response regulator whose function in Arabidopsis is unknown. RT-PCR analysis has shown that expression of the gene takes place in flowers and developing pods with the tissues accumulating different proportions of splice variants. Spatial analysis of expression, using ARR22::GUS plants as a marker, has revealed that the reporter protein accumulates specifically at the junction between the funiculus and the chalazal tissue. Expression can be up-regulated at this location by wounding the developing seed. A detailed analysis has failed to detect ARR22 expression at any other sites and, to support this assertion, the only evidence for tissue ablation in ARR22::Barnase plants is during seed development, with the consequence that embryo growth is attenuated. Ectopic expression of ARR22, driven by either the CaMV 35S or the pea plastocyanin (PPC) promoters, resulted in the generation of plants exhibiting extremely stunted root and shoot growth. No viable progeny could be isolated from the PPC::ARR22 transgenic lines. An RT-PCR analysis of a recently annotated gene (ARR24-At5g26594), that exhibits 66% amino acid similarity to ARR22, has shown that expression is also predominantly in floral and silique tissues. Examination of ARR24::GUS plants has revealed that the activity of the promoter is primarily restricted to pollen grains indicating that this gene is unlikely to display an overlapping function with ARR22. Analyses of individual KO lines of either ARR22 or ARR24 have failed to identify a mutant phenotype under the growth conditions employed and the double knockout ARR22/ARR24 line is also indistinguishable from wild-type plants. These results are discussed in the light of the proposed role of response regulators in plant growth and development.  相似文献   
87.
88.
Great apes are the closest living relatives of humans. Physiological similarities between great apes and humans provide clues to identify which biological features in humans are primitive or derived from great apes. Vitamin A (VA) and carotenoid metabolism have been only partially studied in great apes, and comparisons between great apes and humans are not available. We aimed to investigate VA and carotenoid intake and plasma concentrations in great apes living in captivity, and to compare them to healthy humans. Dietary intakes of humans (n = 20) and, among the great apes, chimpanzees (n = 15) and orangutans (n = 5) were calculated. Plasma retinol (ROH), retinol-binding protein (RBP), retinyl esters, and major carotenoids were analyzed. The great ape diet was higher in VA than in humans, due to high intake of provitamin A carotenoids. Plasma ROH concentrations in great apes were similar to those in humans, but retinyl esters were higher in great apes than in humans. Differences in plasma carotenoid concentrations were observed between great apes and humans. Lutein was the main carotenoid in great apes, while beta-carotene was the main carotenoid for humans. RBP concentrations did not differ between great apes and humans. The molar ratio of ROH to RBP was close to 1.0 in both great apes and humans. In conclusion, great apes show homeostatic ROH regulation, with high but physiological retinyl esters circulating in plasma. Furthermore, great apes show great selectivity in their plasmatic carotenoid concentration, which is not explained by dietary intake.  相似文献   
89.
The amyloid precursor protein (APP) is thought to be neuroprotective following traumatic brain injury (TBI), although definitive evidence at moderate to severe levels of injury is lacking. In the current study, we investigated histological and functional outcomes in APP-/- mice compared with APP+/+ mice following a moderate focal injury, and whether administration of sAPPα restored the outcomes in knockout animals back to the wildtype state. Following moderate controlled cortical impact injury, APP-/- mice demonstrated greater impairment in motor and cognitive outcome as determined by the ledged beam and Barnes Maze tests respectively (p < 0.05). This corresponded with the degree of neuronal damage, with APP-/- mice having significantly greater lesion volume (25.0 ± 1.6 vs. 20.3 ± 1.6%, p < 0.01) and hippocampal damage, with less remaining CA neurons (839 ± 245 vs. 1353 ± 142 and 1401 ± 263). This was also associated with an impaired neuroreparative response, with decreased GAP-43 immunoreactivity within the cortex around the lesion edge compared with APP+/+ mice. The deficits observed in the APP-/- mice related to a lack of sAPPα, as treatment with exogenously added sAPPα post-injury improved APP-/- mice histological and functional outcome to the point that they were no longer significantly different to APP+/+ mice (p < 0.05). This study shows that endogenous APP is potentially protective at moderate levels of TBI, and that this neuroprotective activity is related to the presence of sAPPα. Importantly, it indicates that the mechanism of action of exogenously added sAPPα is independent of the presence of endogenous APP.  相似文献   
90.
The ability to measure and interpret variables associated with feeding behavior and food intake is essential to a variety of nonhuman primate study modalities. The development of a technique to accurately and efficiently measure food intake and meal patterning in captivity will enhance both the interpretation of foraging behavior in the wild as well as our ability to model clinically relevant human feeding pathologies. In this study, we successfully developed the use of a rodent lickometer system to monitor meal patterning in captive common marmosets. We describe the modifications necessary for this type of instrumentation to be used successfully with marmosets. We define variables of interest that relate to both previous rodent literature and human clinical measures. Finally, we relate our findings to potential translational value for both primate field research and biomedical applications. Am. J. Primatol. 74:901‐914, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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