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81.
82.
Hugo Abarca Milana Trubnykova Flix Chavesta Marco Ordez Evelina Rondn 《Biomédica : revista del Instituto Nacional de Salud》2021,41(2):282
Introduction:
Aneuploidies are frequent genetic disorders in clinical practice. However, little is known about other genetic variants that may influence the final phenotype.Objective:
To determine the variations in the number of copies and regions with homozygosity greater than 0.5% or larger than 10 Mb in newborns with autosomal aneuploidies.Materials and methods:
We performed a chromosomal microarray analysis on newborns with autosomal aneuploidies (n=7), trisomy 21 (n=5), and trisomy 18 (n=2) evaluated at the Hospital Antonio Lorena and Hospital Regional of Cusco, Perú, during 2018.Results:
We found pathogenic and probably pathogenic variants in the number of copies in other genomic regions different to chromosomes 21 or 18 in two neonates. Additionally, we found two variants bigger than 500 kpb of unknown pathogenicity.Conclusions:
Although the number of analyzed individuals was small, it is important to highlight that we found other variants in the number of copies that have been described in association with neurodevelopmental disorders, congenital anomalies, deafness, and short/ tall stature, among others, in almost half of them, which will probably impact the phenotype negatively in patients with aneuploidies. 相似文献83.
Strier KB Boubli JP Possamai CB Mendes SL 《American journal of physical anthropology》2006,130(2):227-237
The 957‐ha forest at the Estação Biológica de Caratinga/Reserva Particular do Patrimônio Natural‐Felìciano Miguel Abdala, in Minas Gerais, Brazil, supports one of the largest known populations of the critically endangered northern muriqui (Brachyteles hypoxanthus). We combine long‐term data on one group that has been monitored since 1982 with new data obtained on the other three groups since 2002 and 2003 to describe the demographic structure of this population, evaluate its potential for future growth, and predict how dispersal and competitive regimes may change in response to current demographic conditions. As of January 2005, the 226 individuals in the population were divided into four mixed‐sex groups with 37–77 members, and an all‐male unit whose eight males maintained transient associations with two of the mixed‐sex groups. Although 51.77% of the population was female, the sex ratio among adults and subadults was female‐biased (0.75), while that among immatures was male‐biased (1.47). Consistent with expectations from mean interbirth intervals, 64.18% of adult females gave birth in 2003 and 2004. However, by January 2005, only 52.31% of adult females were still carrying infants <24 months of age due to unusually high infant mortality. First‐year survivorship among the 25 infants born in the population in 2003 was only 76%, considerably lower than previously documented in the longest‐studied group. High female fecundity is indicative of a healthy population, but the current male bias in births will result in a decline in the population growth rate within two decades, and may increase levels of male reproductive competition and alter dispersal patterns. Am J Phys Anthropol, 2006. © 2005 Wiley‐Liss, Inc. 相似文献
84.
Differences in zinc bioavailability among milk and formulas may be attributed to binding of zinc to various ligands. We determined the distribution of zinc and protein at different pHs and zinc and calcium concentrations. We used radiolabelled cow's milk, human milk, whey-predominant (WPF) and casein-predominant (CPF) infant formula. Lowering the pH changed zinc and protein distribution: zinc shifted from pellet (casein) to whey in cow's milk, from fat to whey in human milk and from fat and pellet to whey in formulas. Protein shifted from whey to pellet in human milk and from whey and pellet to fat in formulas. Increasing zinc and calcium concentrations shifted protein and zinc from pellet to whey for cow's milk and from whey and pellet to fat for the formulas. Protein distribution was not affected by calcium or zinc addition in human milk or CPF, while zinc shifted from whey to fat in human milk and from fat and pellet to whey in CPF. Zinc and calcium binding to isolated bovine or human casein increased with pH. At 500 mg/L of zinc, bovine casein bound 32.0 +/- 1.8 and human casein 10.0 +/- 0.9 mg zinc/g protein. At 500 mg/L of calcium, calcium was preferentially bound over zinc. Adding calcium and zinc resulted in 32.0 +/- 1.8 mg zinc/g bound to bovine casein and 17.0 +/- 0.8 mg zinc/g to human casein, while calcium binding was low. Suckling rat pups dosed with 65Zn labelled infant diets were killed and individual tissues were gamma counted. Lower zinc bioavailability was found for bovine milk at pH = 4.0 (%65Zn in liver = 18.7+1.4) when compared to WPF (22.8 +/- 1.6) or human milk (26.9 +/- 0.8). Lowering the pH further decreased zinc bioavailability from human milk, but not from cow's milk or WPF. Knowledge of the compounds binding minerals and trace elements in infant formulas is essential for optimizing zinc bioavailability. 相似文献
85.
Hashimoto O Takagi R Yanuma F Doi S Shindo J Endo H Hasegawa Y Shimasaki S 《Gene》2012,499(2):266-272
Growth differentiation factor-9 (GDF-9), a member of the transforming growth factor-β (TGF-β) superfamily, is expressed exclusively in the oocyte within the ovary and plays essential roles in the ovarian function in mammals. However, a possible involvement of GDF-9 in canine ovarian physiology that has a unique ovulation process among mammals has not been studied. Interestingly, we have isolated two types of cDNA clones generated by an alternative splicing from a canine ovarian total RNA. The predominant long form cDNA shares a common precursor structure with GDF-9s in other species whereas the minor short form cDNA has a 172 amino acid truncation in the proregion. Using a transient expression system, we found that the long form cDNA has a defect in mature protein production whereas the short form cDNA readily produces mature protein. However, mutations at one or two N-glycosylation sites in the mature domain of the short form GDF-9 caused a loss in mature protein production. These results suggest that the prodomain and N-linked glycosylation of the mature domain regulate proper processing and secretion of canine GDF-9. Based on the biological functions of GDF-9, these characteristics of canine GDF-9 could be causatively linked to the unique ovulation process in the Canidae. 相似文献
86.
Morita A Nakahira K Hasegawa T Uchida K Taniguchi Y Takeda S Toyoda A Sakaki Y Shimada A Takeda H Yanagihara I 《Development, growth & differentiation》2012,54(5):588-604
Roberts syndrome and SC phocomelia (RBS/SC) are genetic autosomal recessive syndromes caused by establishment of cohesion 1 homolog 2 ( ESCO 2) mutation. RBS/SC appear to have a variety of clinical features, even with the same mutation of the ESCO2 gene. Here, we established and genetically characterized a medaka model of RBS/SC by reverse genetics. The RBS/SC model was screened from a mutant medaka library produced by the Targeting Induced Local Lesions in Genomes method. The medaka mutant carrying the homozygous mutation at R80S in the conserved region of ESCO2 exhibited clinical variety (i.e. developmental arrest with craniofacial and chromosomal abnormalities and embryonic lethality) as characterized in RBS/SC. Moreover, widespread apoptosis and downregulation of some gene expression, including notch1a, were detected in the R80S mutant. The R80S mutant is the animal model for RBS/SC and a valuable resource that provides the opportunity to extend knowledge of ESCO2. Downregulation of some gene expression in the R80S mutant is an important clue explaining non-correlation between genotype and phenotype in RBS/SC. 相似文献
87.
Adrienne L. Zihlman 《Evolutionary anthropology》2012,21(6):270-276
When “woman‐the‐gatherer” was first proposed as a counter to “man‐the‐hunter,” we were only beginning to understand the many faces of primate females. In ensuing decades we have learned about the skills and talents of female chimpanzees in tool using, hunting, and transmitting behaviors from one generation to the next as teachers, and across space as newcomers to neighboring communities. The perspective of evolutionary time highlights the continuity of female lives from the origin of mammals to the origin of Homo sapiens. The combination of behavioral, fossil, and archeological information aid in reconstructing key ingredients acquired by females along the way that contributed to the success of our species. © 2012 Wiley Periodicals, Inc. 相似文献
88.
目的:研究孕期饮用酒精对子代大鼠学习记忆及海马细胞周期依赖性蛋白激酶5(cdk5)表达的影响。方法:建立大鼠孕期饮用酒精模型,子代成年后,Y-型迷宫测试学习记忆成绩;聚合酶链式反应(RT-PCR)分析海马组织cdk5mRNA的表达;免疫荧光法检测子鼠海马区cdk5蛋白表达。结果:学习记忆测试结果显示孕期饮用酒精组子鼠学习记忆成绩比正常对照组和饮酒对照组明显下降;RT-PCR结果表明孕期饮用酒精组子鼠海马组织cdk5mRNA表达较正常对照组和饮酒对照组明显上升;免疫荧光结果显示孕期饮用酒精组子鼠海马区cdk5蛋白表达明显增加。结论:孕期饮用酒精对子代大鼠的神经损伤可能与cdk5蛋白表达的上调有关。 相似文献
89.
The fibroblast growth factor (FGF) signaling axis plays important roles in heart development. Yet, the molecular mechanism by which the FGF regulates cardiogenesis is not fully understood. Using genetically engineered mouse and in vitro cultured embryoid body (EB) models, we demonstrate that FGF signaling suppresses premature differentiation of heart progenitor cells, as well as autophagy in outflow tract (OFT) myocardiac cells. The FGF also promotes mesoderm differentiation in embryonic stem cells (ESCs) but inhibits cardiomyocyte differentiation of the mesoderm cells at later stages. Furthermore, inhibition of FGF signaling increases myocardial differentiation and autophagy in both ex vivo cultured embryos and EBs, whereas activation of autophagy promotes myocardial differentiation. Thus, a link between FGF signals preventing premature differentiation of heart progenitor cells and suppression of autophagy has been established. These findings provide the first evidence that autophagy plays a role in heart progenitor differentiation, and suggest a new venue to regulate stem/progenitor cell differentiation. 相似文献
90.
Effect of dietary docosahexaenoic acid on biosynthesis of docosahexaenoic acid from alpha-linolenic acid in young rats 总被引:2,自引:0,他引:2
Docosahexaenoic acid (DHA), a crucial nervous system n-3 PUFA, may be obtained in the diet or synthesized in vivo from dietary alpha-linolenic acid (LNA). We addressed whether DHA synthesis is regulated by the availability of dietary DHA in artificially reared rat pups, during p8 to p28 development. Over 20 days, one group of rat pups was continuously fed deuterium-labeled LNA (d5-LNA) and no other n-3 PUFA (d5-LNA diet), and a second group of rat pups was fed a d5-LNA diet with unlabeled DHA (d5-LNA + DHA diet). The rat pups were then euthanized, and the total amount of deuterium-labeled docosahexaenoic acid (d5-DHA) (synthesized DHA) as well as other n-3 fatty acids present in various body tissues, was quantified. In the d5-LNA + DHA group, the presence of dietary DHA led to a marked decrease (3- to 5-fold) in the total amount of d5-DHA that accumulated in all tissues that we examined, except in adipose. Overall, DHA accretion from d5-DHA was generally diminished by availability of dietary preformed DHA, inasmuch as this was found to be the predominant source of tissue DHA. When preformed DHA was unavailable, d5-DHA and unlabeled DHA were preferentially accreted in some tissues along with a net loss of unlabeled DHA from other organs. 相似文献