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21.
Changes in Testicular Interstitial Connective Tissue of Hamsters (Mesocricetus auratus) During Ageing and After Exposure to Short Photoperiod 
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下载免费PDF全文 E Beltrán‐Frutos V Seco‐Rovira C Ferrer J Martínez‐Hernández JF Madrid FJ Sáez M Canteras LM Pastor 《Reproduction in domestic animals》2016,51(1):47-53
The testicular interstitium of Syrian hamster (Mesocricetus auratus) was studied during ageing and in testicular regression after exposure to a short photoperiod, in relation to the interstitial cells and their connective tissue. This tissue was assessed histochemically using Masson's trichrome technique and the expression of Heat Shock Protein 47 (HSP‐47) and collagen IV (α5) was assessed in Leydig cells. Finally, an ultrastructural analysis of some cells of the testicular interstitium was made. Leydig cells were positive for HSP‐47 and collagen IV (α5). Ageing did not change the parameters studied while the short photoperiod altered the synthetic activity of Leydig cells. The positivity index of these cells for HSP‐47 was significantly higher in the regressed testis, but was lower for collagen IV (α5). During ageing no change were observed. Ultrastructural Leydig cells showed a discontinuous basal lamina that did not change during ageing. The basal lamina was not identified in Leydig cells regressed by exposure to a short photoperiod. In conclusion; the intertubular connective tissue suffers little change with age. By contrast, in the testis regressed after exposure to a short photoperiod the studied parameters related to the intertubular connective tissue were altered. These changes are probably related with the low synthetic activity of regressed Leydig cell. 相似文献
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FJ Peña H Rodríguez Martínez JA Tapia C Ortega Ferrusola L González Fernández B Macías García 《Reproduction in domestic animals》2009,44(2):345-349
While, for a long time, the role of mitochondria in sperm physiology and pathology has been largely ignored, recent research points out the mitochondria as a major organelle with key roles in sperm function both under physiological and biotechnological conditions. This paper briefly reviews these novel findings regarding the role of mitochondria in sperm, paying special attention to the most practical, readily applicable, aspects of the topic such as their role as a major source of the sublethal damage that sperm experiments after cryopreservation. 相似文献
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Clare FJ Grant Eric A Lefevre B Veronica Carr Helen Prentice Simon Gubbins Andrew J Pollard Catherine Charreyre Bryan Charleston 《Veterinary research》2012,43(1):68
Understanding the mechanisms that maintain protective antibody levels after immunisation is important for vaccine design. In this study, we have determined the kinetics of plasma and memory B cells detectable in the blood of cattle immunised with model T-dependent or T-independent antigens. Immunisation with the T-D antigen resulted in an expansion of TNP-specific plasma cells post-TNP primary and booster immunisations, which was associated with increased titres of TNP-specific IgG antibodies. Although no TNP-specific memory B cells were detected in the T-D group following the primary immunisation, we detected an increase in the number of TNP-specific memory B cells post-TNP boost. In contrast, no TNP-specific plasma or memory B cells were detected after primary or secondary immunisation with the T-I antigen. We then investigated if immunisation with a third party antigen (tetanus toxin fragment C, TTC) would result in a bystander stimulation and increase the number of TNP-specific plasma and memory B cells in the T-D and/or T-I group. TTC immunisation in the T-D group resulted in a small increase in the number of TNP-specific plasma cells post-TTC primary immunisation and boost, and in an increase in the number of TNP-specific memory B cells post-TTC boost. This bystander effect was not observed in the animals previously immunised with the T-I antigen. In conclusion, the present study characterised for the first time the B cell response in cattle to immunisation with T-D and T-I antigens and showed that bystander stimulation of an established T-D B cell memory response may occur in cattle. 相似文献
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C Ortega‐Ferrusola MC Gil H Rodríguez‐Martínez L Anel FJ Peña P Martín‐Muñoz 《Reproduction in domestic animals》2017,52(6):921-931
Techniques such as mass spectrometry have led to unprecedented knowledge of the proteins that are present in the spermatozoa of humans and other mammals. However, in spite of their high‐throughput and fractioning techniques, most of the techniques in use only offer average values for the entire sperm population. Yet, ejaculate is very heterogeneous, and average values may mask relevant biological information.The application of flow cytometry may overcome this disadvantage, allowing proteomic analysis at the single‐cell level. Moreover, recent advances in cytometry, allowing multiple analyses within a single cell combined with powerful statistical tools, as an expanding subfield in spermatology, are described. The increased use of advanced flow cytometers in andrology laboratories will allow the rapid development of multiparametric, multicolour flow cytometry in andrology that will expand the clinical applications and research possibilities of flow cytometry‐based proteomic approaches, especially in the subfields of clinical andrology and sperm biotechnology. 相似文献
25.
It is widely accepted that sperm morphology is a strong indicator of semen quality. As the sperm head mainly comprises the sperm DNA, it is have been proposed that subtle changes in sperm morphology may be related to abnormal DNA content. Semen from four mongrel dogs was used to investigate DNA quality by means of the sperm chromatin structure assay (SCSA), and for computerized sperm morphometry (CASMA). Each sperm head was measured for nine primary parameters [head area (A), head perimeter (P), head length (L), head width (W), midpiece width (w), midpiece area (a), distance (d) between the major axes of the head and midpiece, angle (theta) of divergence of the midpiece from the head axis] and four parameters of head shape [FUN1, L/W; FUN2, 4piA/P(2); FUN3, (L - W)/(L + W); FUN4, piLW/4A]. Significant differences were found in all CASMA-derived parameters among dogs (p < 0.001). Linear regression models including sperm head shape factors 1, 3 and 4 predicted the extent of DNA denaturation (p < 0.001). We conclude that the CASMA analysis can be considered a powerful tool to improve the spermiogram. 相似文献
26.
Dexmedetomidine and midazolam have synergistic interaction for the sedative/hypnotic and analgesic effects. The purpose of this study was to assess the type of interaction between dexmedetomidine and midazolam for the immobilizing effect in terms of MAC reduction of either halothane (HAL) or isoflurane (ISO). Fifty‐six rats were randomly allocated into one of eight groups (n = 7): SAL + HAL group received saline solution and halothane, SAL + ISO group received saline solution and isoflurane, DEX + HAL group received an intravenous continuous infusion of dexmedetomidine (0.25 μg kg–1minute–1) and halothane, DEX + ISO group received an intravenous continuous infusion of dexmedetomidine (0.25 μg kg–1 minute–1) and isoflurane, MID + HAL group received an intravenous bolus of midazolam (1 mg kg–1) and halothane, MID + ISO group received an intravenous bolus of midazolam (1 mg kg–1) and isoflurane, DEX +MID + HAL group received dexmedetomidine (0.25 μg kg–1 minute–1), midazolam (1 mg kg–1) and halothane and DEX + MID + ISO group received dexmedetomidine (0.25 μg kg–1 minute–1), midazolam (1 mg kg–1) and isoflurane. The tail clamp method was used for MAC determination. Heart rate, invasive arterial blood pressure, respiratory rate and rectal temperature were continuously monitored. Arterial blood gases were analyzed at the end of each experiment. Data were analyzed using a one‐way anova and a Tukey‐Kramer test for multiple comparisons. A p < 0.01 value was considered statistically significant. MAC values were adjusted to the barometric pressure at sea level. Control MACbar values expressed as mean ± SD were 1.31 ± 0.11% for HAL and 1.46 ± 0.05% for ISO. Percentages of MAC reduction were 72 ± 17% for HAL and 43 ± 14% for ISO in DEX groups, 26 ± 11% for HAL and 20 ± 9% for ISO in MID groups, and 90 ± 5% for HAL and 78 ± 5% for ISO in DEX + MID groups. The interaction between dexmedetomidine and midazolam in terms of MAC reduction can be described as additive with halothane and synergistic with isoflurane. 相似文献
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Epigallocatechin‐3‐Gallate (EGCG) Reduces Rotenone Effect on Stallion Sperm–Zona Pellucida Heterologous Binding 下载免费PDF全文
下载免费PDF全文 M Plaza Dávila D Bucci G Galeati FJ Peña G Mari E Giaretta C Tamanini M Spinaci 《Reproduction in domestic animals》2015,50(6):1011-1016
Stallion spermatozoa are highly dependent on oxidative phosphorylation for ATP production to achieve normal sperm function and to fuel the motility. The aim of this study was to evaluate the response of equine sperm under capacitating conditions to the inhibition of mitochondrial complex I by rotenone and to test whether epigallocatechin‐3‐gallate (EGCG), a natural polyphenol component of green tea, could counteract this effect. After 2‐h incubation of stallion spermatozoa in modified Tyrode's medium, rotenone (100 nm , 500 nm and 5 μm ) and EGCG (10, 20 and 60 μm ), alone or in combination, did not induce any significant difference on the percentage of viable cells, live sperm with active mitochondria and spermatozoa with intact acrosome. The inhibition of complex I of mitochondrial respiratory chain of stallion sperm with rotenone exerted a negative effect on heterologous ZP binding ability. EGCG at the concentrations of 10 and 20 μm (but not of 60 μm ) induced a significant increase in the number of sperm bound to the ZP compared with that for control. Moreover, when stallion sperm were treated with rotenone 100 nm , the presence of EGCG at all the concentrations tested (10, 20 and 60 μm ) significantly increased the number of sperm bound to the ZP up to control levels, suggesting that this green tea polyphenol is able to reduce the toxicity of rotenone. 相似文献
29.
Giessibl FJ 《Science (New York, N.Y.)》1995,267(5194):68-71
Achieving high resolution under ultrahigh-vacuum conditions with the force microscope can be difficult for reactive surfaces, where the interaction forces between the tip and the samples can be relatively large. A force detection scheme that makes use of a modified cantilever beam and senses the force gradient through frequency modulation is described. The reconstructed silicon (111)-(7x7) surface was imaged in a noncontact mode by force microscopy with atomic resolution (6 angstroms lateral, 0.1 angstrom vertical). 相似文献
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Strontium isotope ratios measured from core to rim across plagioclase feldspar crystals can be used to monitor changes in the isotope composition of the magma from which they grew. In samples from three magma systems from convergent margin volcanoes, sudden changes in major element composition, petrographic features, and strontium isotope composition were found to correspond to discrete magmatic events, most likely repeated recharge of more mafic magma with lower ratios of strontium-87 to strontium-86 into a crustally contaminated magma. 相似文献