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排序方式: 共有317条查询结果,搜索用时 15 毫秒
71.
《Animal : an international journal of animal bioscience》2016,10(4):655-659
This investigation comprises three trials. Trial 1 consists of an in vitro comparison of three semen extenders: two egg yolk based (customized Tris-egg yolk-glycerol and Triladyl®), the third (AndroMed®) soybean lecithin based. With regard to post-thaw motility, the phytoextender AndroMed® proved to be superior (59±3% v. 53±2% and 53±2%, P<0.05). It had earlier been shown that addition of the commercial prostaglandin F2α preparation Dinolytic® before freezing compromises post-thaw motility; therefore, in Trial 2, Dinolytic® was added after thawing. Frozen-thawed spermatozoa tolerated addition of Dinolytic® at a concentration of 30% (v/v). In Trial 3, cows were inseminated using straws in which diluted semen and Dinolytic® were frozen in the same straw, separated by an air bubble, so intermingling could only take place in the course of insemination. Pregnancy rates at Dinolytic® dosages of 0%, 30% or 60% amounted to 44%, 41% and 56%, respectively (P>0.05), a result that encourages a large-scale field study, which is envisioned. 相似文献
72.
J. Baumgartner I. E. Ezzat Z. Končeková 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(2):264-268
Summary Two experiments were conducted to verify the real possibility for use of the genetic transformation technique as described by Pandey and Patchel in chickens in commercial poultry breeding. Multiple recessive and multiple dominant marker stocks were employed, as well as a tester and a donor line. Recipient tester females were first inseminated with dominant donor semen which was irradiated with doses of 60Co gamma irradiation ranging from 100 to 800 Gy (control group) and 24 h later were reinseminated with unirradiated, normal semen of the recipient strain (experimental group). One genetic transformed chicken was found in the first experiment; no genetic transformed event occurred in the second experiment but one embryo was present in the 600 Gy irradiated group with parthenogenetic development capable of giving a live chick. One hundred Gy was observed not to be enough to destroy completely sperm fertilizing ability. An increased frequency of parthenogenetic development was found in all groups after insemination with irradiated semen. There were 11 individuals with developmental abnormalities from the total of 1264 analysed embryos which died after the 18th day of incubation. We concluded that egg transformation is a rare event in domestic fowl and further research for use of this technique in commercial poultry breeding is needed. 相似文献
73.
Kiziler AR Aydemir B Onaran I Alici B Ozkara H Gulyasar T Akyolcu MC 《Biological trace element research》2007,120(1-3):82-91
We measured the levels of malondialdehyde (MDA), protein carbonyls, glutathione S-transferase (GST) and reducte glutathione (GSH) in seminal plasma and spermatozoa from 95 subjects including 50 infertile
patients to evaluate the association between oxidative stress and damage and the components of the anti-oxidant defenses in
seminal plasma and spermatozoa of infertile subjects and concentrations of cadmium (Cd) and lead (Pb) in the blood and seminal
plasma because of tobacco smoke exposure. The reactive oxygen species (ROS) in spermatozoa were also evaluated by luminol
(5-amino-2,3-dihydro-1,4-phthalazinedione)-enhanced chemiluminescence assay. The sperm count, motility, and morphology in
the smokers infertile group were found to be lower than those in the fertile male group and nonsmokers infertile group (p < 0.001). Concentrations of Cd, Pb, MDA, protein carbonyls, and ROS levels in the smokers infertile group were significantly
higher than those in the fertile male and nonsmokers infertile male groups (p < 0.001). However, GSH levels and GST activities were decreased in the smokers infertile male group than those in the fertile
male and nonsmokers infertile male groups (p < 0.001). The results indicate that smoking could affect semen quality and oxidative lipid and protein damage in human spermatozoa.
From Pearson correlation analysis, positive correlations were demonstrated between the seminal plasma Cd and seminal plasma
protein carbonyls and between seminal plasma Pb and spermatozoa ROS levels in smokers of the subfertile group, while there
was a significant positive correlation between blood Cd and ROS levels in smokers of the fertile group. There was also a significant
negative correlation of the Cd level of the blood and GSH levels of the sperm and seminal plasma. These findings suggest that
cigarette smoking enhances the levels of Cd and Pb in seminal plasma and blood and the extent of oxidative damage associated
with a decrease in components of the anti-oxidant defenses in the sperm of infertile males. 相似文献
74.
Ge-Jee-Bok-Ryung-Hwan (GJBRH), a commonly used herb formulation in Korea, Japan and China, caused a decrease of viability in HeLa human cervical carcinoma cells. The treatment of GJBRH resulted in genomic DNA fragmentation as well as the increase of Sub-G1 portion in cell cycle analysis. In this study, GFP-Bax over-expression system showed that Bax, pro-apoptotic Bcl-2 family protein, was translocated to mitochondria by the presence of GJBRH. The treatment of BAPTA-AM, permeable endogenous calcium chelator, inhibited GJBRH-induced caspase-3 and -9 activations, the release of cytochrome c and Smac/DIABLO into cytoplasm and the resultant cell death in HeLa human cervical carcinoma cells. The treatment of BAPTA-AM increased the expression of XIAP, which mediates binding to and inhibiting caspases and showed protective effect, in GJBRH-treated cells. GJBRH induced the expression of Glucose Response Protein 78 (GRP 78), a positive ER stress marker protein. However, BAPTA-AM did not interfere with the ER-stress response pathway that triggers the expression of GRP 78. This study showed that GJBRH induces cell death, which occurs downstream of or parallel to this point in the ER-stress pathway linked to apoptosis. In conclusion, GJBRH induces apoptosis in HeLa cells via ER stress-pathway associated mitochondria-dependent apoptosis mechansim. 相似文献
75.
Castilla JA Sánchez-León M Garrido A Ramirez JP Clavero A Martínez L 《Cell and tissue banking》2007,8(4):257-265
The publication of European Directive 2004/23/EC in the European Parliament and in the European Council on 31 March 2004 concerning
the setting of standards of quality and safety for the donation, procurement, testing, processing, preservation, storage and
distribution of human cells and tissues made it obligatory for sperm banks to set up quality control systems to ensure, among
other goals, the satisfactory control of all procedures carried out. The objective of the present study is to set out guidelines
that will make it possible to ensure the quality of the donors and frozen specimens accepted and the homogeneity of the samples
supplied by a sperm bank. For this purpose, we shall describe clear-cut criteria for the acceptance of donors and frozen sperm,
taking into account both analytic variability and the biological variations to be expected in semen parameters. Furthermore,
we shall show how the evaluation of the results of a frozen semen specimen, on the basis of analysing a single straw after
such freezing, does not guarantee the homogeneity of all the straws. Therefore, we must design a sampling plan to take into
consideration all the straws obtained from a donor. This kind of plan will depend on different parameters, such as acceptable
levels of quality and the tolerable rate of straws with defective semen, and will involve certain risks, both for the sperm
bank and for the client. The establishment of these acceptance control criteria for frozen specimens and for donors could
be of practical use for the control of the procedures applied in the operation of a sperm bank. 相似文献
76.
Olsen JS DiMaio JT Doran TM Brown C Nilsson BL Dewhurst S 《The Journal of biological chemistry》2012,287(15):11842-11849
Amyloid fibrils contained in semen, known as SEVI, or semen-derived enhancer of viral infection, have been shown to increase the infectivity of HIV dramatically. However, previous work with these fibrils has suggested that extensive time and nonphysiologic levels of agitation are necessary to induce amyloid formation from the precursor peptide (a proteolytic cleavage product of prostatic acid phosphatase, PAP(248-286)). Here, we show that fibril formation by PAP(248-286) is accelerated dramatically in the presence of seminal plasma (SP) and that agitation is not required for fibrillization in this setting. Analysis of the effects of specific SP components on fibril formation by PAP(248-286) revealed that this effect is primarily due to the anionic buffer components of SP (notably inorganic phosphate and sodium bicarbonate). Divalent cations present in SP had little effect on the kinetics of fibril formation, but physiologic levels of Zn(2+) strongly protected SEVI fibrils from degradation by seminal proteases. Taken together, these data suggest that in the in vivo environment, PAP(248-286) is likely to form fibrils efficiently, thus providing an explanation for the presence of SEVI in human semen. 相似文献
77.
Niasari-Naslaji A Mosaferi S Bahmani N Gharahdaghi AA Abarghani A Ghanbari A Gerami A 《Cryobiology》2006,53(1):12-21
The development of a suitable semen extender is required to extend artificial breeding programs and to preserve the genetic potential of Bactrian camel. Experiments were conducted to provide the optimal osmolality and pH of tris-based extender and to compare that with available extenders for short-term preservation of Bactrian camel semen at 4 degrees C during 24 h. In experiments I and II, the effects of varying osmolalities (270, 300, 330, 360, and 390 mOsm/kg) and pHs (5.5, 6, 6.9, 7.5, 7.9, and 8.9) of tris-based extender on sperm viability were investigated. In experiment III, the efficiency of tris-based extender (SHOTOR diluent) in preserving Bactrian camel semen was compared with lactose (10%), sucrose (10%) and Green buffer. Viability parameters including progressive forward motility (PFM), plasma membrane integrity and the percentage of live spermatozoa were assessed. The data were analyzed using general linear model procedure. In the majority of assessments using tris-based extender, the viability of spermatozoa was superior at the osmolality of 330 mOsm/kg and pH of 6.9. PFM was significantly greater at the time of semen dilution in tris-based (65.5%) and Green buffer (60.5%) compared to that of lactose (31%) and sucrose (28%) extenders (P<0.05), and remained elevated throughout the experiment. There was no significant difference in other viability parameters among 4 extenders (P>0.05). In conclusion, the utilization of a tris-based extender, having the osmolality of 330 mOsm/kg and pH of 6.9, favors the short-term preservation of the Bactrian camel spermatozoa under chilled condition. 相似文献
78.
Fundamental knowledge of spermatozoa cryobiology can assist with optimizing cryopreservation protocols needed for genetic management of the endangered black-footed ferret. Objectives were to characterize semen osmolality and assess the influence of two media at various osmolalities on sperm viability. We examined the influence of Ham's F10 +Hepes medium (H) at 270, 400, 500 or 700 mOsm (adjusted with sucrose, a nonpermeating cryoprotectant) and TEST Yolk Buffer (TYB) with 0% (300 mOsm) versus 4% (900 mOsm) glycerol (a permeating cryoprotectant). Electroejaculates (n=16) were assessed for osmolality using a vapor pressure osmometer. For media comparison, semen (n=5) was collected in TYB 0%, split into six aliquots, and diluted in H270, H400, H500, H700, and TYB 0% or TYB 4%. Each sample was centrifuged (300 g, 8 min), resuspended in respective medium, and maintained at 37 degrees C for 3h. Sperm motility and forward progression were monitored every 30 min for 3h post-washing. Acrosomal integrity was monitored at 0 and 60 min post-washing. Results demonstrated that black-footed ferret semen has a comparatively high osmolality (mean+/-SEM, 513.1+/-32.6 mOsm; range, 366-791 mOsm). Ferret spermatozoa were sensitive to hyperosmotic stress. Specifically, sperm motility was more susceptible (P<0.01) to hyperosmotic conditions than acrosomal integrity, and neither were influenced (P>0.05) by hypotonic solutions. Exposure to TYB 4% glycerol retained more (P<0.01) sperm motility than a hyperosmotic Ham's (700 mOsm). These findings will guide the eventual development of assisted breeding with cryopreserved sperm contributing to genetic management of this rare species. 相似文献
79.
Jie Liu Mark Westhusin Gregory Johnson Terje Raudsepp Bhanu Chowdhary Robert Burghardt Charles Long Duane Kraemer 《Animal reproduction science》2009,115(1-4):49-57
Different culture systems were evaluated for their ability to support attachment and proliferation of the somatic cells obtained from ovine semen. Ejaculates (n = 14) were collected from eight rams representing three breeds, Dorper, Suffolk and Hampshire. All samples were processed immediately and somatic cells were obtained from 11 of the 14 ejaculates. These cells had classic epithelial morphology and expressed cytokeratin, indicating they were of epithelial origin. Cells from four rams with the greatest growth rates were used for subsequent studies. Cells were cultured in four different media for 5 days and total numbers of attached cells vs. total numbers of seeded cells were counted and compared each day. Four media were evaluated: (1) a supplemented medium composed of DMEM/F12, 10% fetal bovine serum (FBS), 10 ng/ml epidermal growth factor, 30 μg/ml bovine pituitary extract, 5 μg/ml insulin, 10 ng/ml cholera toxin, and 50 μg/ml gentamycin; (2) sheep fetal fibroblast (SFF)-conditioned medium; (3) swiss 3T3 fibroblast-conditioned medium; and (4) basic medium composed of DMEM/F12, 10% FBS, and 50 μg/ml gentamycin. Cell proliferation was greater in the supplemented medium, SFF-conditioned medium, and 3T3 fibroblast-conditioned medium compared to the basic medium by day 2 of culture (p < 0.05, n = 24), and greater in supplemented medium compared to the SFF-conditioned medium and 3T3 fibroblast-conditioned medium by day 4 of culture (p < 0.05, n = 24). Three different surfaces: (1) Matrigel basement membrane matrix-coated plastic; (2) collagen I-coated plastic; and (3) uncoated plastic were evaluated for their ability to support proliferation and attachment of the cells obtained from semen. Cell proliferation was greater when cells were cultured on the Matrigel-coated compared to the collagen I-coated and uncoated plastic by day 2 of culture (p < 0.05, n = 16). Cell attachment was greater when cells were plated on the Matrigel-coated and collagen I-coated plastic compared to the uncoated plastic (p < 0.05, n = 16). These studies describe an effective system for the culture and proliferation of epithelial cells obtained from ovine semen samples. The system may increase the likelihood of obtaining cells from frozen semen, which could be used for cloning to recover animals of genetic value in which semen is the only material that is available. 相似文献
80.
Wani NA 《Animal reproduction science》2009,111(1):69-79
Experiments were conducted to study the effect of storing epididymal spermatozoa, in tris-tes- and tris-lactose egg yolk extenders, on their fertilizing ability and subsequent in vitro embryo development. Ovaries and testes were collected from a local slaughterhouse in normal saline solution (NSS) at 37 degrees C and on ice (0-1 degrees C), respectively. Cumulus oocyte complexes (COCs) aspirated from the follicles were randomly distributed to 4-well culture plates (20-25COCs/well) containing 500 microL of maturation medium and cultured at 38.5 degrees C in an atmosphere of 5% CO(2) in air for 36 h. Spermatozoa were collected from the cauda epididymides in syringes containing 2-3 mL of either tris-tes- or tris-lactose egg yolk extender. They were cooled down slowly and stored at refrigeration (4 degrees C) temperature. The spermatozoa were evaluated for motility and used for IVF of IVM oocytes on the day of collection and after 2, 4, 6 and 8 days of storage. On the day of IVF, spermatozoa were prepared by the swim up technique and both spermatozoa and oocytes were co-incubated at 38.5 degrees C in a humidified atmosphere of 5% CO(2) in air for 15-16 h. Presumptive zygotes were either fixed and stained with Hoechst 33342 for evaluation of fertilization or were cultured in 500 microL of the culture medium at 38.5 degrees C in an atmosphere of 5% CO(2), 5% O(2) and 90% N(2) in air. There was no significant difference (P>0.05) in the proportion of oocytes fertilized with spermatozoa stored in either of the two extenders for up to 8 days. The proportion of oocytes that cleaved (43-60%) and those that developed to blastocysts (14-21%) did not show any difference (P>0.05) either, when spermatozoa from different days of storage were used. First cleavage was observed as early as 16 h after IVF, early blastocysts had developed by day 4, expanded blastocysts after day 5 and hatching of blastocysts started after day 6 of culture. It may be concluded that dromedary epididymal spermatozoa survive in storage for at least 8 days in tris-lactose- and tris-tes egg yolk diluents at 4 degrees C. These spermatozoa maintain fertilizing ability and may be suitable for use in IVF and other assisted reproductive procedures. 相似文献