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ZS Perényi O Szenci PV Drion H Banga-Mboko NM Sousa B El Amiri JF Beckers 《Reproduction in domestic animals》2002,37(6):324-329
Pregnancy‐associated glycoproteins (PAGs) isolated from the placenta of various ruminant species are enzymatically inactive members of the aspartic proteinase family. The measurement of these proteins in the maternal blood can be a good indicator of the presence of a live embryo. As certain aspartic proteinases are present in biological fluids in physiological and pathological conditions at various concentrations, it was necessary to determine the specificity of three radioimmunoassay (RIA) systems currently used for the detection of PAG molecules. Commercially available members of the aspartic proteinase family like pepsinogen, pepsin, chymosin, rennet, cathepsin D and renin were tested in a wide concentration range (10 ng/ml – 1 mg/ml). Pepsinogen cross‐reacted in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 50 μg/ml and 500 μg/ml concentrations, respectively. In the presence of pepsin, cross‐reaction was observed in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 500 μg/ml and 1 mg/ml concentrations, respectively. Chymosin and rennet could cross‐react in RIA 2 and RIA 3, while renin and cathepsin D did not decrease the binding of the tracer to antisera more, than that of the minimal detection limit. As the plasma/serum concentrations of the examined aspartic proteinases reported in the literature were outside the concentration range where cross‐reaction was observed, it can be concluded that these RIA systems were specific for the detection of PAGs in biological fluids. 相似文献
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Reduction in the mRNA expression of sVEGFR1 and sVEGFR2 is associated with the selection of dominant follicle in cows 
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下载免费PDF全文 PV Ortega Serrano A Guzmán CG Hernández–Coronado H Castillo‐Juárez AM Rosales‐Torres 《Reproduction in domestic animals》2016,51(6):985-991
The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post‐selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non‐dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development. 相似文献
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Letícia Aparecida de Moraes Julio Massaharu Marubayashi Valdir Atsushi Yuki Murad Ghanim Vinicius Henrique Bello Bruno Rossitto De Marchi Leonardo da Fonseca Barbosa Laura M. Boykin Renate Krause-Sakate Marcelo Agenor Pavan 《Phytoparasitica》2017,45(4):517-525
In Brazil, the first major invasion event of Bemisia tabaci was that of Middle East–Asia Minor 1 (MEAM1) species, formerly termed as B biotype, which commenced in the 1990s mainly by ornamental plants in São Paulo State. More than two decades after this invasion, the presence of the Mediterranean (MED) species of B. tabaci, formerly Q biotype, was reported in Rio Grande do Sul, the southernmost State of Brazil, and now in São Paulo and Paraná States, in southeastern Brazil. Specimens of whiteflies collected from commercial begonia, hydrangea, petunia and poinsettia greenhouses in São Paulo, and also from begonias and poinsettias collected in flower shops in Paraná, were all identified as belonging to MED species. Furthermore, the secondary endosymbionts Arsenophonus, Hamiltonella and Rickettsia of MED from São Paulo and Paraná were detected by PCR and their presence confirmed by sequencing and FISH analysis, and those results differed from MED detected in Rio Grande do Sul that harbored only Hamiltonella and Cardinium. Our results suggest a new MED invasion into Brazil and is associated with ornamental plants. The two MED populations are genetically different and suggest that they are separate invasions. 相似文献
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In vitro Development of Buffalo Oocytes in Media-containing Fluids from Different Size Class Follicles 总被引：1，自引：0，他引：1
S Nandi HM Raghu BM Ravindranatha PSP Gupta PV Sarma 《Reproduction in domestic animals》2004,39(1):33-38
Studies were conducted to investigate the effect of supplementation of fluid from different sized class [small (SFF, < 3 mm), medium (MFF, 3-8 mm) and large (LFF, > 8 mm)] of normal and cystic (CFF) ovarian follicles in oocyte culture media on oocyte maturation rate and embryo development in vitro and to test the efficacy of follicular fluid (FF) from different size classes as a whole oocyte maturation medium. Results suggested that FF were capable of developing buffalo oocytes to embryonic stage in vitro although its efficacy was lower than that of serum. Regardless of high maturation rates after in vitro maturation (IVM) in media containing FF or IVM in whole FF, low blastocyst rates were obtained after in vitro fertilization (IVF) and culture of embryos. Follicular fluid from small follicles had significantly (p < 0.05) higher potential of developing buffalo oocytes to embryonic stage in vitro than that from medium and large follicles. Cystic FF was not capable of supporting development of buffalo oocytes in vitro. 相似文献
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JM Morrell B Persson H Tjellström A Laessker H Nilsson M Danilova PV Holmes 《Reproduction in domestic animals》2005,40(6):522-525
In the absence of commercially viable methods for cryopreserving turkey spermatozoa, new processing methods are required to extend the functional life of stored turkey spermatozoa for artificial insemination. The present study evaluates the efficacy of a new extender (Turkey Semen Extend) and investigates the use of density gradient centrifugation in processing turkey spermatozoa for artificial insemination. The new extender is compared with two commercially available turkey semen extenders, Beltsville Poultry Semen Extender and Ovodyl. Turkey spermatozoa in Turkey Semen Extend were still motile 20 h after collection, representing a considerable improvement over the other semen extenders (40%, 0% and 8% for Turkey Semen Extend, Beltsville Poultry Semen Extender and Ovodyl, respectively). A field trial on a commercial turkey farm showed improved fertilization rates following insemination of turkey hens with semen extended in Turkey Semen Extend (89.7%) compared with Beltsville Poultry Semen Extender (86.9%). This difference is statistically significant (p < 0.05). Processing on a density gradient, optimized for turkey spermatozoa, also increased sperm survival (50% gradient-prepared spermatozoa still motile after 18 h compared with <10% non-processed spermatozoa). Preliminary studies indicate that gradient preparation of spermatozoa may aid survival during cryopreservation. 相似文献
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N J MacLachlan P V Rossitto H W Heidner L G Iezzi T D Yilma C D DeMaula B I Osburn 《Veterinary microbiology》1992,31(4):303-316
Neutralizing epitopes present on field isolates of bluetongue virus (BTV) serotypes 10, 11, 13 and 17 were evaluated with a panel of polyclonal and neutralizing monoclonal antibodies (MAbs). A total of 91 field isolates were evaluated, including 15 isolates of BTV-10, 29 isolates of BTV-11, 26 isolates of BTV-13, and 21 isolates of BTV-17. The viruses were isolated from cattle, goats, sheep, elk and deer in Idaho, Louisiana, Nebraska and, predominantly, California, in the years 1979, 1980 and 1981. The isolates were analyzed and compared using a panel of neutralizing MAbs which included five MAbs raised against BTV-2, seven against BTV-10, five against BTV-13, and six against BTV-17. Neutralization patterns obtained with the MAb panel and individual field isolates were compared to those obtained with prototype viruses of each serotype. All field isolates were neutralized by at least some of the MAbs raised against the prototype virus of the same serotype. All field isolates of BTV-10 were neutralized by the seven MAbs raised to BTV-10, whereas the field isolates of BTV-11, BTV-13 and BTV-17 were not consistently neutralized by all of the MAbs raised against the prototype virus of the same serotype. Variation in neutralizing epitopes recognized by the MAb panel was most pronounced amongst the field isolates of BTV-17. A one-way cross neutralization was evident between BTV-10 and BTV-17 as all field isolates of BTV-17 were neutralized by four of the MAbs raised against BTV-10. In contrast, no BTV-10 isolates were neutralized by the MAbs raised against BTV-17. Differences in the MAb neutralization patterns of field isolates of BTV-11, BTV-13 and BTV-17 suggest that the immunogenic domain responsible for their neutralization is plastic, such that individual epitopes within the domain may vary in their significance to the neutralization of different viruses, even of the same serotype. The apparent conservation of neutralizing epitopes on field isolates of BTV-10 suggests that the field isolates may be derived from the modified-live vaccine strain of BTV-10. 相似文献
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PV Hobbs JS Reid RA Kotchenruther RJ Ferek R Weiss 《Science (New York, N.Y.)》1997,275(5307):1776-1778
Airborne measurements in smoke from biomass burning in Brazil have yielded optical parameters that permit an improved assessment of the effects of smoke on Earth's radiation balance. The global-mean direct radiative forcing due to smoke from biomass burning worldwide is estimated to be no more than about -0.3 watt per square meter (cooling), compared with +2.45 watts per square meter (warming) due to anthropogenic greenhouse gases. On regional scales, direct radiative forcing due to smoke can be large and might indirectly affect global climate. 相似文献