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51.
Thirteen sets of monozygotic (MZ) twins from an extended multi-generation family are reported. Zygosity was determined by interviewing families for overall physical similarity and by assessment of facial photographs. A hypothetical gene was traced back five generations to a common grandfather. Familial monozygotic twinning in this pedigree is compatible with autosomal dominant inheritance with reduced penetrance. Other plausible mechanisms of inheritance are discussed. 相似文献
52.
A set of 34 molecular dynamic (MD) simulations totaling 305 ns of simulation time of the prion protein-derived peptide PrP106-126 was performed with both explicit and implicit solvent models. The objective of these simulations is to investigate the relative stability of the alpha-helical conformation of the peptide and the mechanism for conversion from the helix to a random-coil structure. At neutral pH, the wild-type peptide was found to lose its initial helical structure very fast, within a few nanoseconds (ns) from the beginning of the simulations. The helix breaks up in the middle and then unwinds to the termini. The spontaneous transition into the random coil structure is governed by the hydrophobic interaction between His(111) and Val(122). The A117V mutation, which is linked to GSS disease, was found to destabilize the helix conformation of the peptide significantly, leading to a complete loss of helicity approximately 1 ns faster than in the wild-type. Furthermore, the A117V mutant exhibits a different mechanism for helix-coil conversion, wherein the helix begins to break up at the C-terminus and then gradually to unwind towards the N-terminus. In most simulations, the mutation was found to speed up the conversion through an additional hydrophobic interaction between Met(112) and the mutated residue Val(117), an interaction that did not exist in the wild-type peptide. Finally, the beta-sheet conformation of the wild-type peptide was found to be less stable at acidic pH due to a destabilization of the His(111)-Val(122), since at acidic pH this histidine is protonated and is unlikely to participate in hydrophobic interaction. 相似文献
53.
Noraina Mohd Bakri Siti Fatimah Ibrahim Nurul Atikah Osman Nurhaslina Hasan Farah Hanan Fathihah Jaffar Zulaiha Abdul Rahman Khairul Osman 《Saudi Journal of Biological Sciences》2016,23(1):S50-S55
Apoptosis is a programed cell death that is vital for tissue homeostasis. However, embryo apoptosis had been known to be related to embryo fragmentation which should be avoided in in vitro fertilization (IVF). The purpose of this study was to evaluate the relationship of embryo apoptosis with the grade of immature oocytes and cleavage stage of in vitro produced (IVP) cattle embryos. This study consisted of 345 oocytes collected through ovary slicing. Immature oocytes were graded as A, B and C. This grading was based on cumulus cell thickness and compactness. All oocytes then underwent an in vitro maturation (IVM) procedure. An IVF was done 24 h after IVM culture. Prior to staining, stage of cleaved embryos was determined and classified as either 2, 4, 8 or >8-cell embryo stage. Apoptosis status of cleaved IVP embryos was determined by using annexin V-FITC staining technique at 48 and 72 h post insemination (hpi). Apoptosis status for each embryo was classified as either early or late. The result showed that there was no significant difference (p > 0.05) of apoptosis status among grade A, B and C embryos. All grades of oocytes showed embryo apoptosis where 1.5% late apoptosis for grade A, 4.5% and 10.4% of early and late apoptosis for grade B and grade C. Early apoptosis was not seen in grade A embryo. We also noted no significant difference (p > 0.05) of apoptosis status between 2, 4, 8 and >8-cell embryo stage. Early apoptosis was also not seen in >8-cell stage. Even though there were no differences in apoptosis expression between the three classes, the cleavage rate of grade A oocytes was significantly higher (p < 0.01) than grade B and grade C. In conclusion, the apoptosis expression in the embryo can occur regardless of the oocyte quality and the cleavage stage of the embryo produced.Abbreviations: ART, assisted reproductive technologies; BO, Brackett and Oliphant; BSA, bovine serum albumin; CaI, calcium ionophore; CC, cumulus cells; COC, cumulus–oocyte complex; CO2, carbon dioxide; CR1aa, Charles Rosenkran’s 1 amino acid; DNA, deoxyribonucleic acid; DO, denuded oocyte; EA, early apoptosis; FBS, fetal bovine serum; FITC, fluorescein isothiocyanate; FSH, follicle stimulating hormone; GSH, glutathione; hpi, hours post insemination; IVC, in vitro culture; IVF, in vitro fertilization; IVM, in vitro maturation; IVP, in vitro produced; LA, late apoptosis; LH, luteinizing hormone; PBS, phosphate buffered saline; PI, propidium iodide; PS, phosphatidylserine; TUNEL, terminal deoxynucleotidyl transfer-mediated dUTP nick end-labeling. 相似文献
54.
Guotai Yu Nicolas Champouret Burkhard Steuernagel Pablo D. Olivera Jamie Simmons Cole Williams Ryan Johnson Matthew J. Moscou Inmaculada Hernández-Pinzón Phon Green Hanan Sela Eitan Millet Jonathan D. G. Jones Eric R. Ward Brian J. Steffenson Brande B. H. Wulff 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(6):1207-1222
Key message
We identified two novel wheat stem rust resistance genes, Sr-1644-1Sh and Sr-1644-5Sh in Aegilops sharonensis that are effective against widely virulent African races of the wheat stem rust pathogen.Abstract
Stem rust is one of the most important diseases of wheat in the world. When single stem rust resistance (Sr) genes are deployed in wheat, they are often rapidly overcome by the pathogen. To this end, we initiated a search for novel sources of resistance in diverse wheat relatives and identified the wild goatgrass species Aegilops sharonesis (Sharon goatgrass) as a rich reservoir of resistance to wheat stem rust. The objectives of this study were to discover and map novel Sr genes in Ae. sharonensis and to explore the possibility of identifying new Sr genes by genome-wide association study (GWAS). We developed two biparental populations between resistant and susceptible accessions of Ae. sharonensis and performed QTL and linkage analysis. In an F6 recombinant inbred line and an F2 population, two genes were identified that mapped to the short arm of chromosome 1Ssh, designated as Sr-1644-1Sh, and the long arm of chromosome 5Ssh, designated as Sr-1644-5Sh. The gene Sr-1644-1Sh confers a high level of resistance to race TTKSK (a member of the Ug99 race group), while the gene Sr-1644-5Sh conditions strong resistance to TRTTF, another widely virulent race found in Yemen. Additionally, GWAS was conducted on 125 diverse Ae. sharonensis accessions for stem rust resistance. The gene Sr-1644-1Sh was detected by GWAS, while Sr-1644-5Sh was not detected, indicating that the effectiveness of GWAS might be affected by marker density, population structure, low allele frequency and other factors.55.
Heat shock proteins (HSPs) are molecular chaperones involved in protein folding, assembly and transport, and which play critical roles in the regulation of cell growth, survival and differentiation. We set out to test the hypothesis that HSP27 protein is expressed in the human testes and its expression varies with the state of spermatogenesis. HSP27 expression was examined in 30 human testicular biopsy specimens (normal spermatogenesis, maturation arrest and Sertoli cell only syndrome, 10 cases each) using immunofluorescent methods. The biopsies were obtained from patients undergoing investigations for infertility. The seminiferous epithelium of the human testes showing normal spermatogenesis had a cell type-specific expression of HSP27. HSP27 expression was strong in the cytoplasm of the Sertoli cells, spermatogonia, and Leydig cells. Alternatively, the expression was moderate in the spermatocytes, weak in the spermatids and absent in the spermatozoa. In testes showing maturation arrest, HSP27 expression was strong in the Sertoli cells, weak in the spermatogonia, and spermatocytes. It was absent in the spermatids and Leydig cells. In Sertoli cell only syndrome, HSP27 expression was strong in the Sertoli cells and absent in the Leydig cells. We report for the first time the expression patterns of HSP27 in the human testes and show differential expression during normal spermatogenesis, indicating a possible role in this process. The altered expression of this protein in testes showing abnormal spermatogenesis may be related to the pathogenesis of male infertility. 相似文献
56.
Oslob JD Romanowski MJ Allen DA Baskaran S Bui M Elling RA Flanagan WM Fung AD Hanan EJ Harris S Heumann SA Hoch U Jacobs JW Lam J Lawrence CE McDowell RS Nannini MA Shen W Silverman JA Sopko MM Tangonan BT Teague J Yoburn JC Yu CH Zhong M Zimmerman KM O'Brien T Lew W 《Bioorganic & medicinal chemistry letters》2008,18(17):4880-4884
This communication describes the discovery of a novel series of Aurora kinase inhibitors. Key SAR and critical binding elements are discussed. Some of the more advanced analogues potently inhibit cellular proliferation and induce phenotypes consistent with Aurora kinase inhibition. In particular, compound 21 (SNS-314) is a potent and selective Aurora kinase inhibitor that exhibits significant activity in pre-clinical in vivo tumor models. 相似文献
57.
The sensitivity and accuracy of molecular diagnosis of Salmonella from meat and poultry products using polymerase chain reaction (PCR) was compared with conventional microbiological methods. A total of 212 samples representing the most frequently used fresh and frozen meat and poultry products (whole, cut, ground, and processed) were collected from different locations within the city of Irbid. DNA was extracted directly from each food sample and amplified using Salmonella-specific primers. Samples were also analysed using conventional microbiological methods for the presence of Salmonella spp. Results showed that Salmonella was detected in 185 samples out of 212 (87%) by PCR technique, while 172 (81%) samples were detected Salmonella positive by conventional microbiological methods. On the other hand, 27 (12.7%) samples were negative by PCR and 40 (18.8%) samples were negative by conventional microbiological methods. PCR assay proved to be an effective method for Salmonella detection in meat and poultry products with high specificity and sensitivity and more importantly a less time-consuming procedure. Using PCR, Salmonella spp. detection could be achieved within 24–36 h compared to 3–8 days for the conventional microbiological methods. 相似文献
58.
Ashraf M Shoma Madiha H Mohamed Nashaat Nouman Mahmoud Amin Ibtihal M Ibrahim Salwa S Tobar Hanan E Gaffar Warda F Aboelez Salwa E Ali Soheir G William 《World journal of surgical oncology》2009,7(1):1-10
Background
Proximal major limb amputations due to malignant tumors have become rare but are still a valuable treatment option in palliation and in some cases can even cure. The aim of this retrospective study was to analyse outcome in those patients, including the postoperative course, survival, pain, quality of life, and prosthesis usage.Methods
Data of 45 consecutive patients was acquired from patient's charts and contact to patients, and general practitioners. Patients with interscapulothoracic amputation (n = 14), shoulder disarticulation (n = 13), hemipelvectomy (n = 3) or hip disarticulation (n = 15) were included.Results
The rate of proximal major limb amputations in patients treated for sarcoma was 2.3% (37 out of 1597). Survival for all patients was 42.9% after one year and 12.7% after five years. Survival was significantly better in patients with complete tumor resections. Postoperative chemotherapy and radiation did not prolong survival. Eighteen percent of the patients with malignant disease developed local recurrence. In 44%, postoperative complications were observed. Different modalities of postoperative pain management and the site of the amputation had no significant influence on long-term pain assessment and quality of life. Eighty-seven percent suffered from phantom pain, 15.6% considered their quality of life worse than before the operation. Thirty-two percent of the patients who received a prosthesis used it regularly.Conclusion
Proximal major limb amputations severely interfere with patients' body function and are the last, albeit valuable, option within the treatment concept of extremity malignancies or severe infections. Besides short survival, high complication rates, and postoperative pain, patients' quality of life can be improved for the time they have remaining. 相似文献59.
Sharifa Alkandari Fatima Al-Hassawi Ahmed Aldughpassi Jiwan S. Sidhu Hanan A. Al-Amiri Amani Al-Othman Nissar Ahmed Anwar Ahmad 《Saudi Journal of Biological Sciences》2021,28(10):5547
The objective of this research work was to produce acceptable quality functional foods, namely, extruded snacks, digestive biscuits and pan bread, on a pilot scale, using vitamin E and β-carotene-rich red palm olein (RPOL) and red palm shortening (RPS). These products were evaluated for their chemical composition and sensory quality along with the antioxidants and vitamin contents during the six months of storage at room temperature (22 ± 1 °C). Extruded snacks and digestive biscuits prepared with RPOL and RPS were found to be good sources of these antioxidant vitamins. The average β-carotene content of the control and test snacks at the end of six months of storage ranged from 26.8 to 56.1 mg/kg fat, and from 430.9 to 468.9 mg/kg fat, respectively. The total vitamin E content in control and test snacks made in Plant No. 1 decreased after six months of storage from 786.1 to 704.4 mg/kg fat, and from 765.1 to 695.4 mg/kg fat, respectively. As expected, the total tocotrienol content was four to five times higher than the total tocopherols in control biscuits. The RPOL containing 600–750 ppm of carotenes (mainly α- and β-carotenes), 710–774 ppm of vitamin E, was found to be suitable for industrial application in producing acceptable quality pan bread, digestive biscuits and snacks. These functional foods contained significant amounts of β-carotene and total vitamin E, indicating the possibility of producing such foods rich in these two of the important antioxidant vitamins coming from a natural source. The research findings strongly indicate that good-quality pan bread, extruded snacks and digestive biscuits can successfully be produced to offer healthier eating choices to the consumers of this region, thereby promoting better health and productivity among the population. 相似文献
60.
Hanan Sela Smadar Ezrati Pnina Ben-Yehuda Jacob Manisterski Eduard Akhunov Jan Dvorak Adina Breiman Abraham Korol 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(11):2453-2463