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We analyzed genetic diversity of 215 mitochondrial DNA (mtDNA) D‐loop sequences from seven populations of domesticated helmeted guinea fowl (Numida meleagris) in Nigeria and compared that with results of samples collected in Kenya (n = 4) and China (n = 22). In total, 241 sequences were assigned to 22 distinct haplotypes. Haplotype diversity in Nigeria was 0.693 ± 0.022. The network grouped most matrilines into two main haplogroups: A and B. There was an absence of a geographic signal, and two haplotypes dominated across all locations with the exception of the Kebbi population in the northwest of the country; AMOVA also confirmed this observation (FST = 0.035). The low genetic diversity may be a result of recent domestication, whereas the lack of maternal genetic structure likely suggests the extensive genetic intermixing within the country. Additionally, the differentiation of the Kebbi population may be due to a certain demographic history and/or artificial selection that shaped its haplotype profile. The current data do not permit us to make further conclusions; therefore, more research evidence from genetics and archaeology is still required.  相似文献   
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<正>Domestication of livestock involves drastic phenotypic changes driven by strong artificial selection, such as tame behavior and coat color. These abundant phenotypic variations established during animal domestication have provided valuable resources to study the evolutionary mechanisms underlying  相似文献   
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Guenons (tribe Cercopithecini) are the most widely distributed nonhuman primate in the tropical forest belt of Africa and show considerable phenotypic, taxonomic, and ecological diversity. However, genomic information for most species within this group is still lacking. Here, we present a high-quality de novo genome (total 2.90 Gb, contig N50 equal to 22.7 Mb) of the mona monkey (Cercopithecus mona), together with genome resequencing data of 13 individuals sampled across Nigeria. Our results showed differentiation between populations from East and West of the Niger River ∼84 ka and potential ancient introgression in the East population from other mona group species. The PTPRK, FRAS1, BNC2, and EDN3 genes related to pigmentation displayed signals of introgression in the East population. Genomic scans suggest that immunity genes such as AKT3 and IL13 (possibly involved in simian immunodeficiency virus defense), and G6PD, a gene involved in malaria resistance, are under positive natural selection. Our study gives insights into differentiation, natural selection, and introgression in guenons.  相似文献   
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A series of oxovanadium(IV) symmetrical tetradentate Schiff base complexes have been isolated from the reaction of VOSO4 with Schiff bases obtained from the condensation of 2-hydroxybenzophenone or 2-hydroxy-5-chlorosalicylaldehyde with various aliphatic diamines. The compounds were characterized by elemental analyses, 1H NMR, infrared, electron paramagnetic resonance, electronic spectral, cyclic voltammetry and room temperature magnetic susceptibility measurements. The solution EPR spectra are consistent with square pyramidal complexes with C4v symmetry. The IR spectra confirmed that the complexes are all monomeric except for [VO(Clsal)2tn] which polymerizes via OV?VO linkages. The electronic spectra indicate a square pyramidal geometry in both non-coordinating and coordinating solvents except for [VO(bp2-pn)] which appears to be octahedral in DMSO. The room temperature magnetic moments of 1.7-1.8 B.M. are normal for V(IV) d1 configuration. Evidence for electrochemical pseudo-reversibility is presented for four of the complexes. In vitro studies revealed that two of the compounds, [VO(bp2-en] and [VO(bp2-tn)MeOH], significantly increased glucose uptake when compared to the basal glucose uptake in transformed and sensitized C1C12 cells, but not at the same level as insulin.  相似文献   
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ObjectiveAn experiment was conducted to determine the standardized ileal digestibility (SID) of amino acids (AA) in fish meal (FM) and blood-derived protein sources including spray-dried porcine plasma (SDPP), porcine red blood cells (PRBC), and blood meal (BM) fed to growing pigs.MethodsTen barrows (mean initial body weight of 22.1±1.54 kg) surgically fitted with T-cannulas at the distal ileum were allotted to a duplicated 5×4 incomplete Latin square design with 5 experimental diets and 4 periods. Four experimental diets were prepared to contain FM, SDPP, PRBC, or BM as the sole source of nitrogen. A nitrogen-free diet was prepared and included to estimate the basal ileal endogenous losses of AA. For the 7-day experimental period, pigs were fed for 5 days as adaptation, and ileal digesta samples were collected for 9 hours on days 6 and 7.ResultsThe SID of crude protein in BM (48.0%) was less (p<0.05) than in FM, SDPP, and PRBC (83.4%, 83.9%, and 87.3%, respectively). Pigs fed the diet containing BM had less (p<0.05) SID of AA, except isoleucine and proline, than those fed the diet containing FM, SDPP, or PRBC. Among FM, SDPP, and PRBC, there was no difference in the SID of crude protein and all AA, except isoleucine. The SID of isoleucine in PRBC and BM (62.7% and 48.3%, respectively) was less (p<0.05) than in FM and SDPP (88.0% and 84.9%, respectively). The SID of lysine in FM, SDPP, PRBC, and BM was 85.4%, 84.9%, 89.7%, and 51.9%, respectively.ConclusionThe SID of most AA was not different among FM, SDPP, and PRBC, but BM had lower SID of most AA than FM, SDPP, and PRBC.  相似文献   
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Obesity results in reduced differentiation potential of adipocytes leading to adipose tissue insulin resistance. Elevated proinflammatory cytokines from adipose tissue in obesity, such as TNFα have been implicated in the reduced adipocyte differentiation. Other mediators of reduced adipocyte differentiation include TGFβ and wnt proteins. Although some overlap exists in the signaling cascades of the wnt and TGFβ pathways it is unknown if TGFβ or wnt proteins reciprocally induce the expression of each other to maximize their biological effects in adipocytes. Therefore, we investigated the possible involvement of TGFβ signaling in wnt induced gene expression and vice versa in 3T3-L1 adipocyte. Effect of TGFβ and Wnt pathways on differentiation was studied in preadipocytes induced to differentiate in the presence of Wnt3a or TGFβ1 and their inhibitors (FZ8-CRD and SB431542, respectively). Regulation of intracellular signaling and gene expression was also studied in mature adipocytes. Our results show that both TGFβ1 and Wnt3a lead to increased accumulation of β-catenin, phosphorylation of AKT and p44/42 MAPK. However, differences were found in the pattern of gene expression induced by the two proteins suggesting that distinct, but complex, signaling pathways are activated by TGFβ and wnt proteins to independently regulate adipocyte function.  相似文献   
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Erythrocyte plasma membranes of non-insulin dependent diabetic humans (NIDDM) and healthy humans were prepared by hypotonic lysis. The specific activity of (Na+–K+)-ATPase of NIDDM membranes, both in the absence and presence of digoxin were lower than the specific activity of normal enzymes (83.6 percent and 74.0 percent of the normal enzyme respectively). Addition of digoxin decreased the activity of this enzyme (38.0 percent in NIDDM and 30.0 percent in normal enzyme).Although the affinity of the pump for ATP was similar in both membranes of NIDDM and normal humans (Km for ATP=19.9±0.24M ATP and 20.0±0.21 M ATP respectively), the Vmax of NIDDM membranes was more than 20 percent lower than that of the normal enzyme. The specific activity of Mg2+-dependent Ca2+-pumping ATPase (Ca2+–Mg2+)-ATPase) of NIDDM membrane was lower than 80 percent of the specific activity of the normal enzymes. While the affinity of the pump for ATP was lower in the membranes of NIDDM (Km for ATP=50.0±4.3 M ATP) in comparison to normal membranes (Km for ATP=63.1±38M ATP), the Vmax of NIDDM membranes was similar to the normal enzyme. Altogether, these findings suggest that both the (Na+–K+)-ATPase and Ca2+-pumping ATPase of NIDDM membranes are less functional than the enzymes in normal erythrocytes.  相似文献   
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