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111.
Zebu cattle are notorious for poor fertility characterized by late maturity and long intercalving intervals attributed to a variety of factors, including genetic, nutritional and climatic. The aim of the present investigation, therefore, was to induce fertile estrus in acyclic pubertal heifers and postpartum anestrous Zebu cows by hormonal intervention. Pubertal Hariana and Sahiwal anestrous heifers (n=51) and postpartum cows (n=55) were either assigned a placebo (controls, N=6 for each breed and parity) or treated with 10-d norgestomet (3 mg) subcutaneous ear implants, with an initial injection of 3 mg, im norgestomet + 5 mg estradiol valerate, followed by 500 IU eCG at implant withdrawal (NOR-treated groups). Jugular venous plasma samples were obtained from a total of 28 animals (controls : 4 heifers and 4 cows; NOR-treated : 12 heifers and 8 cows) on Days 0 (implant insertion), 3, 7, 9 and Day 10 (implant withdrawal), every 12 h on Days 11 and 12, and then once daily on Days 17, 24 and 31. All the samples were assayed for progesterone. Almost all (97%) heifers and 81% cows were induced to estrus, the majority (92% heifers and 79% cows) within 120 h of implant removal. Synchrony of the induced estrus was better in cows, but interval to estrus and estrus duration were significantly longer in heifers (P<0.05). Post-treatment fertility, based on Day 28 nonretum rate, first service, and overall conception rates, was better in heifers (78.9, 60.5 and 73.7%, respectively) than cows (77.1, 48.6 and 62.9%, respectively), but the differences were significant only for the overall pregnancy rate (71.8% for heifers and 51.2% for cows; P<0.05). Low pre-treatment plasma progesterone values (<0.5ng/mL) were consistent with ovarian inactivity, confirming the true anestrus status of experimental animals. Controls failed to exhibit estrus and maintained low progesterone concentrations throughout the study. In treated animals, high progesterone values from Day 17 onwards suggested ovulatory estrus. These early luteal phase progesterone concentrations in nonpregnant (P=0.06) and nonpregnant, nonretum (P<0.05) animals were low in comparison with those of pregnant animals. Good fertility resulting from breeding according to estrus, inspite of variable intervals to estrus and estrus duration, advocates its advantage over fixed-time insemination in norgestomet-treated anestrous Zebu cattle. 相似文献
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N. Khurana R. K. Saxena R. Gupta R. C. Kuhad 《World journal of microbiology & biotechnology》1993,9(3):353-356
Microcycle conidiation in Trichoderma hamatum and T. harzianum has been achieved in complete darkness for the first time. The time required for mass conidiation without intervening vegetative growth was decreased to 24 h instead of 6 to 7 days. The conidia produced by microcycle conidiation were viable and had pigmentation and antagonistic behaviour similar to those of the parental stock cultures.N. Khurana, R.K. Saxena, R. Gupta and R.C. Kuhad are with the Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi-110021, India. 相似文献
113.
Shayan Khalafi Shoumin Zhu Rimpi Khurana Ines Lohse Silvia Giordano Simona Corso Hassan Al-Ali Shaun P. Brothers Claes Wahlestedt Stephan Schürer Wael El-Rifai 《Translational oncology》2022,15(1)
Gastric cancer (GC) is frequently characterized by resistance to standard chemotherapeutic regimens and poor clinical outcomes. We aimed to identify a novel therapeutic approach using drug sensitivity testing (DST) and our computational SynerySeq pipeline. DST of GC cell lines was performed with a library of 215 Federal Drug Administration (FDA) approved compounds and identified clofarabine as a potential therapeutic agent. RNA-sequencing (RNAseq) of clofarabine treated GC cells was analyzed according to our SynergySeq pipeline and identified pictilisib as a potential synergistic agent. Clonogenic survival and Annexin V assays demonstrated increased cell death with clofarabine and pictilisib combination treatment (P<0.01). The combination induced double strand breaks (DSB) as indicated by phosphorylated H2A histone family member X (γH2AX) immunofluorescence and western blot analysis (P<0.01). Pictilisib treatment inhibited the protein kinase B (AKT) cell survival pathway and promoted a pro-apoptotic phenotype as evidenced by quantitative real time polymerase chain reaction (qRT-PCR) analysis of the B-cell lymphoma 2 (BCL2) protein family members (P<0.01). Patient derived xenograft (PDX) data confirmed that the combination is more effective in abrogating tumor growth with prolonged survival than single-agent treatment (P<0.01). The novel combination of clofarabine and pictilisib in GC promotes DNA damage and inhibits key cell survival pathways to induce cell death beyond single-agent treatment. 相似文献
114.
Ebsy Jaimon Aashutosh Tripathi Arohi Khurana Dipanjana Ghosh Jini Sugatha Sunando Datta 《The Journal of biological chemistry》2021,297(6)
ARL5B, an ARF-like small GTPase localized to the trans-Golgi, is known for regulating endosome-Golgi trafficking and promoting the migration and invasion of breast cancer cells. Although a few interacting partners have been identified, the mechanism of the shuttling of ARL5B between the Golgi membrane and the cytosol is still obscure. Here, using GFP-binding protein (GBP) pull-down followed by mass spectrometry, we identified heat shock cognate protein (HSC70) as an additional interacting partner of ARL5B. Our pull-down and isothermal titration calorimetry (ITC)-based studies suggested that HSC70 binds to ARL5B in an ADP-dependent manner. Additionally, we showed that the N-terminal helix and the nucleotide status of ARL5B contribute to its recognition by HSC70. The confocal microscopy and cell fractionation studies in MDA-MB-231 breast cancer cells revealed that the depletion of HSC70 reduces the localization of ARL5B to the Golgi. Using in vitro reconstitution approach, we provide evidence that HSC70 fine-tunes the association of ARL5B with Golgi membrane. Finally, we demonstrated that the interaction between ARL5B and HSC70 is important for the localization of cation independent mannose-6-phosphate receptor (CIMPR) at Golgi. Collectively, we propose a mechanism by which HSC70, a constitutively expressed chaperone, modulates the Golgi association of ARL5B, which in turn has implications for the Golgi-associated functions of this GTPase. 相似文献
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Mutations in the human sulphate transporter gene, DTDST, have been implicated in several diseases. Analysis of affected patients has linked disease symptoms to faulty sulphate transporter activity. We have reproduced two of these mutations in SHST1, a homologous member of the family isolated from the tropical legume, Stylosanthes hamata. Both mutations significantly reduce sulphate transport activity of SHST1. These results indicate that conserved residues between distinct members of the family may share essential roles in structure or function. The results also suggest that putative helix 9 may be important for stability and/or trafficking of SHST1 to the plasma membrane. 相似文献
119.
Various factors, such as quality of the oocyte, oxygen tension, embryo density, and kind of energy substrate during in vitro production of embryos may affect the rate of preimplantation embryo development. In the present study we used 12553 bovine oocytes aspirated from slaughterhouse ovaries to evaluate various culture conditions that would increase in vitro production of advanced stages of preimplantation embryos. The morphological quality of the oocyte based on the compactness and number of layers of cumulus cells had significant positive effects on the rates of in vitro maturation, fertilization and development to the morula and blastocyst stages. None of the corona-enclosed or nude oocytes progressed beyond the 8- to 16-cell stage. The level of oxygen (5 or 20%) did not affect the proportion of one-cell embryos undergoing cleavage or progressing to morula and blastocyst stages. The rate of development of one-cell embryos originating from inferior quality oocytes was significantly improved when cultured in groups of 40 instead of 20 embryos per 0.5 mL medium. In the presence of cumulus cells, glucose had beneficial effects on in vitro maturation and subsequent development of IVM-IVF zygotes. The presence of serum improved the rate of in vitro development of one-cell embryos. Minimum Essential Medium supplemented with energy substrates according to the findings of metabolic studies was less effective in supporting in vitro maturation and subsequent development than TCM-199. In conclusion, morphological grading of immature oocytes is an appropriate selection criterion for their developmental ability. Embryo yields from low quality oocytes can be increased by culturing them in large groups. Serum is not essential for in vitro generation of embryos but its addition improves rates of success. 相似文献
120.
Influence of Seed Size on Seedling Growth of Albizia procera Under Different Soil Water Levels 总被引:5,自引:0,他引:5
Albizia procera Benth. is an early successional leguminous treespecies that occurs naturally in dry tropical forests in India.The growth response of seedlings of A. procera from seeds ofdifferent sizes was studied under four soil water levels. Seedswere surface sterilized, germinated and grown in a glasshousefor 3 weeks under optimal water supply, and were subsequentlymaintained at four soil water levels for 4 months. Soil matricpotentials for 1, 相似文献