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Samuel Guemra Eriko da Silva Santo Renato Zanin Paulo Sergio Monzani Tobias Canan Sovernigo Otávio Mitio Ohashi Cláudia Lima Verde Leal Paulo Roberto Adona 《Theriogenology》2014
Ovum pick up (OPU) associated with in vitro production (IVP) of embryos has been shown as an important tool in cattle breeding to increase the number of descendants from animals of high genetic value. In herds maintained distant from the laboratory, collecting cumulus–oocyte complexes (COCs) and transporting them to the laboratory may take several hours and decrease COCs viability, representing a challenge for commercial settings. In this study, a prematuration culture to induce temporary meiosis block was evaluated in a commercial scale IVP setting as a strategy to transport bovine OPU-derived COCs from Nelore and Brangus donors. Effects on embryo yield and pregnancy rates were assessed. Viable COCs from each donor were destined to one of the experimental groups (control, blocks 1 and 2). Control group COCs were placed in cryotubes with 1 mL TCM199–HEPES. In block groups (1 and 2), COCs were placed in cryotubes with 300 μL TCM 199 + 12 μM butyrolactone I (block medium). All groups were gassed and kept in a thermos bottle for 4 hours at 36 °C. Next, COCs in the control group were transferred to IVM medium and block 1 group to block medium, and cultured for 22 hours and 15 hours, respectively, at 38.5 °C and 5% CO2 in air. Block 2 COCs were kept in the cryotubes and in the thermos bottle for another 15 hours at 36 °C to simulate long-term transport conditions. After meiosis block in prematuration culture, blocks 1 and 2 COCs were matured in vitro for 22 hours as for the control group. After IVM, COCs in all groups were submitted to IVF and IVC, and blastocyst rates were evaluated on day 7. Embryos were transferred and pregnancy rates evaluated at 60 days of gestation. The mean total number of COCs retrieved by OPU did not differ between Nelore and Brangus donors (16.8 and 17.2, respectively, P > 0.05), but Nelore donors produced more viable COCs than Brangus (10.1 and 7.6, respectively, P < 0.05) and more embryos/cow (3.8 and 2.7, respectively, P < 0.05). Blastocyst rates were similar for control (40.2% and 36.7%), block 1 (37.3% and 34.5%), and block 2 groups (34.7% and 33.6%) for Nelore and Brangus cattle, respectively (P > 0.05). Pregnancy rates did not differ regardless of breed or treatment (36.7%, P > 0.05). In conclusion, temporary meiosis block during prematuration culture did not affect embryo development or pregnancy rates; therefore, this strategy may be used to transport bovine COCs in a commercial IVP setting. 相似文献
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Baris Gulcu Derya Ulug Canan Hazir Mehmet Karagoz 《Biocontrol Science and Technology》2014,24(8):965-970
In laboratory studies, we demonstrated that five native entomopathogenic nematode species/isolates caused 100% mortality of Spodoptera cilium larvae, a soil surface-feeding pest of turfgrass. At 25 infective juveniles/cm2 applied to sod, two selected Turkish species, Steinernema carpocapsae and Heterorhabditis bacteriophora (Sarigerme isolate), averaged 77% and 29% larval mortality, respectively. 相似文献
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Canan Aslan Nevin Çelebi İ. Tuncer Değim Ayşegül Atak Çiğdem Özer 《AAPS PharmSciTech》2017,18(4):1019-1030
The aim of this study was to develop and characterize rh- IL-2 loaded chitosan-based nanogels for the healing of wound incision in rats. Nanogels were prepared using chitosan and bovine serum albumin (BSA) by ionic gelation method and high temperature application, respectively. Particle size, zeta potential, and polydispersity index were measured for characterization of nanogels. The morphology of nanogels was examined by using SEM and AFM. The IL-2 loading capacity of nanogels was determined using ELISA method. In vitro release of IL-2 from nanogels was performed using Franz diffusion cells. Artificial neural network (ANN) models were developed using selected input parameters (stirring rate, chitosan%, BSA%, TPP%) where particle size was an output parameter for IL-2 free nanogels. Wound healing effect of IL-2 loaded chitosan-TPP nanogel was evaluated by determining the malondialdehyde (MDA) and glutathione (GSH) levels of wound tissues in rats. The particle size of IL-2 loaded chitosan-TPP nanogels was found to be larger than that of IL-2 loaded BSA-based chitosan nanogels. Drug loading capacity of nanogels was found 100%?±?0.010 for both nanogels. IL-2 was released slowly after the initial burst effect. According to SEM and AFM imaging, BSA-chitosan nanogel particles were of nanometer size and presented a swelling tendency, and chitosan-TPP nanogel particles were found to be spherical and homogenously dispersed. IL-2 loaded chitosan-TPP nanogel was found suitable for improving wound healing because it decreased the MDA levels and increased the GSH levels wound tissues comparing to control group. 相似文献
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Pollen morphology of 10 taxa from Turkey, four of them endemic, belonging to the genus Petrorhagia (Caryophyllaceae), P. alpina subsp. alpina, P. alpina subsp. olympica, P. cretica, P. dubia, P. hispidula, P. lycica, P. pamphylica, P. peroninii, P. prolifera and P. saxifraga, has been investigated using light (LM) and scanning electron (SEM) microscopy. Pollen morphology differences among these
taxa have been determined. The pollen type of investigated taxa is polyporate (12–22-porate), sphaeroidal, the exine exhibits
a tectate structure and a microechinate ornamentation. Petrorhagia alpina subsp. alpina has the smallest pollen grain diameter (18.57 μm) and P. dubia the largest one (37.80 μm). The number of pores ranges from 12 (in P. dubia and P. saxifraga) to 22 (in P. alpina subsp. alpina and P. alpina subsp. olympica and P. hispidula) with a minimum pore diameter of 2.37 μm in P. alpina subsp. alpina and a maximum pore diameter of 4.23 μm in P. peroninii. The exine thickness ranges from 1.73 μm in P. saxifraga to 3.78 μm in P. pamphylica. In this study, the systematic implications are discussed in the light of palynological results. 相似文献
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Cacina C Bulgurcuoglu-Kuran S Iyibozkurt AC Yaylim-Eraltan I Cakmakoglu B 《Molecular biology reports》2012,39(2):1225-1229
In this study, we aimed to investigate a possible association between the Stromal cell-derived factor-1 (SDF-1) and CXCR4 polymorphisms and the risk of developing endometrial carcinoma. SDF-1 3??A and CXCR4 gene polymorphisms was performed by polymerase chain reaction (PCR) and restriction fragment length polymorphism in 139 healthy individuals and 113 patients with endometrial carcinoma. In our study groups SDF-1 3??A AA genotype frequency was higher in patients that of controls and individuals who had AA genotype showed a 2.6-fold increased risk for endometrial cancer. The carriers of CXCR4 T allele were higher in patients compared with controls and individuals who had TT genotype had a 2.5-fold high risk for endometrial carcinoma. Our finding suggest that there was no significant association between the (SDF-1) and CXCR4 polymorphisms and endometrium cancer risk. Further studies in a larger population are needed to better elucidate the role of (SDF-1) and CXCR4 gene polymorphisms in the risk of endometrial carcinogenesis. To the best of our knowledge, this is the first study to show such an association. 相似文献
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The past decade has witnessed the development and success of coarse‐grained network models of proteins for predicting many equilibrium properties related to collective modes of motion. Curiously, the results are usually robust toward the different cutoff distances used for constructing the residue networks from the knowledge of the experimental coordinates. In this study, we present a systematical study of network construction and their effect on the predicted properties. Probing bond orientational order around each residue, we propose a natural partitioning of the interactions into an essential and a residual set. In this picture, the robustness originates from the way with which new contacts are added, so that an unusual local orientational order builds up. These residual interactions have a vanishingly small effect on the force vectors on each residue. The stability of the overall force balance then translates into the Hessian as small shifts in the slow modes of motion and an invariance of the corresponding eigenvectors. We introduce a rescaled version of the Hessian matrix and point out a link between the matrix Frobenius norm based on spectral stability arguments and orientational local order. A recipe for the optimal choice of partitioning the interactions into essential and residual components is prescribed. Implications for the study of biologically relevant properties of proteins are discussed with specific examples. Proteins 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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Hamarat M Yenilmez A Erkasap N Isikli B Aral E Koken T Can C Demirustu CB 《The Chinese journal of physiology》2010,53(3):145-150
The aim of the study was to evaluate protective effects of exogenous leptin on ischemia/reperfusion (I/R)-induced injuries to the urinary bladder tissue and to investigate the effect on tumor necrosis factor alpha (TNF-alpha) levels and apoptotic cells during I/R injury. Bladder I/R injury was induced by abdominal aorta occlusion by ischemia for 45 min, followed by 60 min of reperfusion in rats. The rats were divided into three groups: control (n = 8 + 8), I/R (n = 8 + 8) and I/R+leptin group (n = 8 + 8). The rats in the I/R+leptin group were treated intraperitoneally with leptin (10 microg/kg) 60 min prior to ischemia induction. At the end of the reperfusion period, urinary bladders of the first eight rats from each group were removed for TUNEL staining processing while the others were removed for biochemical analyses for MDA and TNF-alpha levels. In the I/R group, the ratios of TUNEL-positive nuclei were higher than the control and the I/R+leptin groups. The MDA and TNF-alpha levels of the bladder tissue in the I/R group were higher than the control and leptin-treated groups. TUNEL-staining and biochemical studies revealed that leptin has a protective effect on urinary bladder I/R injury. 相似文献