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G Elamaran KP Singh MK Singh SK Singla MS Chauhan RS Manik P Palta 《Reproduction in domestic animals》2012,47(6):1027-1036
This study examined the effects of O2 concentration (5% vs 20%) during in vitro maturation (IVM), fertilization (IVF) and culture (IVC) or supplementation of IVM and IVC media with cysteamine (50 and 100 μm , respectively; IVM, IVF and IVC carried out in 20% O2), on blastocyst rate and relative mRNA abundance of some apoptosis‐related genes measured by real‐time qPCR in immature and in vitro‐matured buffalo oocytes and in embryos at 2‐, 4‐, 8‐ to 16‐cell, morula and blastocyst stages. The blastocyst rate was significantly higher (p < 0.05) while the percentage of TUNEL‐positive cells was significantly lower (p < 0.05) under 5% O2 than that under 20% O2. The mRNA expression of anti‐apoptotic genes BCL‐2 and MCL‐1 was significantly higher (p < 0.05) and that of pro‐apoptotic genes BAX and BID was lower (p < 0.05) under 5% O2 than that under 20% O2 concentration at many embryonic stages. Following cysteamine supplementation, the blastocyst rate and the relative mRNA abundance of BCL‐XL and MCL‐1 was significantly higher (p < 0.05) and that of BAX but not BID was lower (p < 0.05) at many stages of embryonic development, although it did not affect the percentage of TUNEL positive cells in the blastocysts significantly. The mRNA expression pattern of these genes during embryonic development was different in 5% vs 20% O2 groups and in cysteamine supplemented vs controls. At the 8‐ to 16‐cell stage, where developmental block occurs in buffalo, the relative mRNA abundance of BCL‐2 and MCL‐1 was highest under 5% O2 concentration and that of BAX and BID was highest (p < 0.05) under 20% O2 concentration. These results suggest that one of the mechanisms through which beneficial effects of low O2 concentration and cysteamine supplementation are mediated during in vitro embryo production is through an increase in the expression of anti‐apoptotic and a decrease in the expression of pro‐apoptotic genes. 相似文献
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V Vescoli L Degiorgi W Henderson G Gruner KP Starkey LK Montgomery 《Science (New York, N.Y.)》1998,281(5380):1181-1184
Optical experiments were conducted on a series of organic linear chain conductors with different values of the interchain single-electron transfer integral tb, which quantifies the degree of anisotropy. Electron-electron interactions together with Umklapp scattering resulted in a correlation gap and an insulating state for small tb. An insulator-to-metal transition was observed when tb exceeded a critical value, on the order of the correlation gap Egap. The absence of a plasma edge on the insulator side of the transition for polarization perpendicular to the chains suggests that the electrons are confined to the chains. The optical features of the metallic state, when contrasted with the magnetic properties, are suggestive of spin-charge separation. 相似文献
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MSD Marley MD Givens PK Galik KP Riddell DA Stringfellow 《Reproduction in domestic animals》2009,44(3):532-535
The purpose of this study was to determine whether or not embryos derived from in vitro fertilization of oocytes from persistently infected (PI) cattle would contain infectious virus. Three in vitro embryo production treatment groups were assessed: 1) oocytes and uterine tubal cells (UTC) free of bovine viral diarrhoea virus (BVDV) (negative control), 2) oocytes free of BVDV fertilized and cultured in media containing UTC obtained from PI heifers, and 3) oocytes from PI heifers fertilized and cultured in media containing UTC free of BVDV. The developmental media, UTC and embryos (individual or groups of five) were assayed for virus. Virus was not isolated from any samples in treatment group 1. As shown in previous studies, a proportion of embryo samples were positive for BVDV in treatment group 2. In treatment group 3, the virus associated with the oocytes contaminated the developmental media and infected susceptible co-culture cells used during fertilization and culture. In addition, 65% (11/17) of the degenerated ova from treatment group 3 had infectious virus associated with them. While none of the ova developed into transferable embryos, the study did confirm that use of oocytes from PI cows could lead to amplification of BVDV and cross contamination during in vitro embryo production. 相似文献
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Sibeko KP Collins NE Oosthuizen MC Troskie M Potgieter FT Coetzer JA Geysen D 《Veterinary parasitology》2011,181(2-4):120-130
Restriction fragment length polymorphism analysis of PCR products (PCR-RFLP) and sequencing of the variable region of the p104 and PIM genes was performed on samples obtained from South African T. parva parasites originating from cattle on farms with suspected theileriosis and from buffalo. p104 and PIM PCR-RFLP profiles similar to those of the T. parva Muguga stock, an isolate that causes ECF in Kenya, were obtained from three of seven cattle samples collected on a farm near Ladysmith in KwaZulu-Natal Province. Amino acid sequences of the p104 and PIM genes from two of these samples were almost identical to the T. parva Muguga p104 and PIM sequences. This result supports findings from a recent p67 study in which p67 alleles similar to those of the T. parva Muguga stock were identified from the same samples. While these results suggest the presence of a cattle-derived T. parva parasite, reports of cattle-to-cattle transmission could not be substantiated and ECF was not diagnosed on this farm. Although extensive diversity of p104 and PIM gene sequences from South African T. parva isolates was demonstrated, no sequences identical to known cattle-type p104 and PIM alleles were identified from any of the buffalo T. parva samples analyzed. 'Mixed' PIM alleles containing both cattle- and buffalo-type amino acid motifs were identified for the first time, and there appeared to be selection of cattle-type and 'mixed'-type PIM sequences in the cattle samples examined. 相似文献
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Sibeko KP Oosthuizen MC Collins NE Geysen D Rambritch NE Latif AA Groeneveld HT Potgieter FT Coetzer JA 《Veterinary parasitology》2008,155(1-2):37-48
Corridor disease, caused by the tick-borne protozoan parasite Theileria parva, is a controlled disease in South Africa. The Cape buffalo is the reservoir host and uninfected buffalo have become sought-after by the game industry in South Africa, particularly for introduction into Corridor disease-free areas. A real-time polymerase chain reaction (PCR) test for detection of T. parva DNA in buffalo and cattle was developed to improve the sensitivity and specificity of the official diagnostic test package in South Africa. Oligonucleotide primers and hybridization probes were designed based on the 18S ribosomal RNA (rRNA) gene. Amplification of control DNA using Theileria genus-specific primers resulted in detection of T. taurotragi and T. annulata, in addition to T. parva. A T. parva-specific forward primer was designed which eliminated amplification of all other Theileria species, except for Theileria sp. (buffalo); however only the T. parva product was detected by the T. parva-specific hybridization probe set. The real-time PCR assay requires less time to perform, is more sensitive than the other molecular assays previously used in T. parva diagnostics and can reliably detect the parasite in carrier animals with a piroplasm parasitaemia as low as 8.79 x 10(-4)%. 相似文献
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Sibeko LN Dhansay MA Charlton KE Johns T Van Stuijvenberg ME Gray-Donald K 《Public health nutrition》2004,7(6):813-820
OBJECTIVE: There is a paucity of data on the micronutrient status of low-income, lactating South African women and their infants under 6 months of age. The aim of this study was to elucidate the level of anaemia and vitamin A deficiency (VAD) in peri-urban breast-feeding women and their young infants. DESIGN: Cross-sectional study including anthropometric, biochemical and infant feeding data.Setting: Peri-urban settlement in Cape Town, South Africa. SUBJECTS: Breast-feeding women (n=113) and their infants (aged 1-6 months) attending a peri-urban clinic. RESULTS: Mean (standard deviation (SD)) haemoglobin (Hb) of the lactating mothers was 12.4 (1.3) g dl(-1), with 32% found to be anaemic (Hb<12 g dl(-1)). Maternal serum retinol was 49.8 (SD 13.3) microg dl(-1), with 4.5% VAD. Using breast milk, mean (SD) retinol concentration was found to be 70.6 (24.6) microg dl(-1) and 15.7 (8.3) microg/g milk fat, with 13% below the cut-off level of <8 microg/g fat. There was no correlation found between breast milk retinol and infant serum retinol. Z-scores (SD) of height-for-age, weight-for-age and weight-for-height were -0.69 (0.81), 0.89 (1.01) and 1.78 (0.83), respectively. Mean (SD) infant Hb was 10.9 (1.1) g dl(-1), with the prevalence of anaemia being 50%, 33% and 12% using Hb cut-offs below 11 g dl(-1), 10.5 g dl(-1) and 9.5 g dl(-1), respectively. Mean (SD) infant serum retinol was 26.9 (7.2) microg dl(-1), with 10% being VAD. None of the infants was exclusively breast-fed, 22% were predominantly breast-fed and 78% received complementary (mixed) breast-feeding. Thirty-two per cent of infants received weaning foods at an exceptionally young age (< or =1 month old). CONCLUSION: A high rate of anaemia is present in lactating women residing in resource-poor settings. Moreover, their seemingly healthy infants under 6 months of age are at an elevated risk of developing early-onset anaemia and at lower risk of VAD. 相似文献
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A Yadav KP Singh MK Singh N Saini P Palta RS Manik SK Singla RC Upadhyay MS Chauhan 《Reproduction in domestic animals》2013,48(5):858-865
For investigating the effects of physiologically relevant heat shock, buffalo oocytes/embryos were cultured at 38.5°C (control) or were exposed to 39.5°C (Group II) or 40.5°C (Group III) for 2 h once every day throughout in vitro maturation (IVM), fertilization (IVF) and culture (IVC). Percentage of oocytes that developed to 8‐cell, 16‐cell or blastocyst stage was lower (p < 0.05) and the number of apoptotic nuclei was higher (p < 0.05) for Group III > Group II > controls. At both 8–16‐cell and blastocyst stages, relative mRNA abundance of stress‐related genes HSP 70.1 and HSP 70.2 and pro‐apoptotic genes CASPASE‐3, BID and BAX was higher (p < 0.05) in Groups III and II than that in controls with the exception of stress‐related gene HSF1. Expression level of anti‐apoptotic genes BCL‐XL and MCL‐1 was also higher (p < 0.05) in Groups III and II than that in controls at both 8–16‐cell and blastocyst stages. Among the genes related to embryonic development, at 8–16‐cell stage, the expression level of GDF9 was higher (p < 0.05) in Group III than that in controls, whereas that of GLUT1, ZAR1 and BMP15 was not significantly different among the three groups. At the blastocyst stage, relative mRNA abundance of GLUT1 and GDF9 was higher (p < 0.05) in Group II than that in controls, whereas that of ZAR‐1 and BMP15 was not affected. The results of this study demonstrate that exposure of buffalo oocytes and embryos to elevated temperatures for duration of time that is physiologically relevant severely compromises their developmental competence, increases apoptosis and affects stress‐, apoptosis‐ and development‐related genes. 相似文献
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MK Singh KP Singh D Kumar RA Shah T Anand MS Chauhan RS Manik SK Singla P Palta 《Reproduction in domestic animals》2013,48(2):284-291
When buffalo embryonic stem (ES) cell–like cells that expressed surface markers SSEA‐4, TRA‐1‐60, TRA‐1‐81, CD9 and CD90 and intracellular markers OCT4, SOX2 and FOXD3, as shown by immunofluorescence, and that expressed REX‐1 and NUCLEOSTEMIN as confirmed by RT‐PCR, were subjected to suspension culture in hanging drops in absence of LIF and buffalo foetal fibroblast feeder layer support, they differentiated to form three‐dimensional embryoid bodies (EBs). Of 231 EBs examined on Day 3 of suspension culture, 141 (61.3 ± 3.09%) were of compact type, whereas 90 (38.4 ± 3.12%) were of cystic type. The cells obtained from EBs were found to express NF‐68 and NESTIN (ectodermal lineage), BMP‐4 and α‐skeletal actin (mesodermal lineage), and α‐fetoprotein, GATA‐4 and HNF‐4 (endodermal lineage). When these EBs were cultured on gelatin‐coated dishes, they spontaneously differentiated to several cell types such as epithelial‐ and neuron‐like cells. When EBs were cultured in the presence of 1 or 2% DMSO or 10?8 m or 10?7 m retinoic acid for 25 days, ES cells could be directed to form muscle cell–like cells, the identity of which was confirmed by expression of α‐actinin by immunofluorescence and of MYF‐5, MYOD and MYOGENIN genes by RT‐PCR. MYOD was first detected on Day 10 in both treatment groups and on Day 15 in controls, whereas MYOGENIN was first detected on Day 10, Day 15 and Day 25 in the presence of retinoic acid, in the presence of DMSO and in controls, respectively. The present study demonstrates the ability of buffalo ES cell–like cells to undergo directed differentiation to cells of skeletal myogenic lineage. 相似文献