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1.
Genital papillomatosis in sperm whale bulls   总被引:1,自引:0,他引:1  
Examination of 31 male sperm whales (Physeter catodon) caught off the western coast of Iceland revealed three cases of genital papillomatosis involving the unsheathed penis. One subadult and two sexually mature bulls were affected. Gross lesions resembled papillomas common in terrestrial mammalian species. Transmission electron microscopy of these lesions revealed nonenveloped intranuclear virus particles 28-40 nm in diameter and round to hexagonal in shape. In two cases immunoperoxidase staining was negative for group-specific papillomavirus antigen. These findings indicate that the spectrum of animal species affected with virus-associated genital papillomatosis includes at least one globally distributed species of the order Cetacea (whales, dolpins, and porpoises).  相似文献   

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The solution behavior of sperm whale metmyoglobin in 0.15 I phosphate-chloride buffer, pH 7.2, has been examined by sedimentation equilibrium, frontal gel chromatography, and sedimentation velocity. Results obtained from all three studies are shown to be consistent with a self-association model in which dimerization of the myoglobin is governed by an association equilibrium constant of 0.068 liter/g (580 M-1) at 20 degrees C.  相似文献   

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Bull sperm heads and tails have been separated by proteolytic digestion (trypsin) and plasma membranes have been isolated, using discontinuous sucrose density gradient centrifugation. Plasma membrane bound Ca2+-ATPase is shown to be associated mostly with the tail membranes. Pyrene excimer fluorescence and diphenylhexatriene fluorescence polarization experiments indicate a more fluid lipid phase in the tail region. Differences in surface charge distribution have been found, using 1-anilinonaphthalene-8-sulfonate and Tb3+ as fluorescent probes.  相似文献   

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The present study was undertaken to evaluate the protein composition of the sperm membranes (SM) of Nelore bulls, assessing protein markers associated with bull fertility, and whether these markers can be used for predicting bull fertility. Samples were obtained of 20 Nelore bulls, with fertility ranked and divided into three groups (greater, normal and least). To rank the bull's fertility weighted classification was used (according to the number of pregnant cows, number of AI cows and number of herds, considering three different breeding seasons), using the PROC GENMOD as a statistical model, with 99% significance. A total of 7897 Nelore cows, randomly distributed among 28 different farms, were considered in the statistical analyses. The bulls were divided into three fertility groups (pregnancy rates): greater (%F > 80), normal (79 < %F > 71) and least (< 68%F) with 3, 13 and 4 bulls, respectively. Two-dimensional gel electrophoresis (2DE) of sperm membranes indicated in 27 spots (SM40, SM53, SM69, SM93, SM102, SM111, SM137, SM138, SM189, SM196, SM201, SM202, SM204, SM225, SM236, SM237, SM239, SM241, SM246, SM247, SM275, SM283, SM342, SM346, SM355, SM372, SM391) was prevalent in the higher fertility group, and just one spot (SM244) was prevalent in the lower fertility group. Spots SM244 and SM239 had their identification defined by PMF/MALDI-MS, as BSP-A3 and aSFP, respectively. Both these proteins showed a great potential for predicting bull's fertility. The amount of aSFP was 8.5 times greater in the sperm membrane protein profile of the higher fertility groups of Nelore bulls. Besides that, the BSP-A3 was 2.5 times greater in the lower fertility group. For the other spots potentially associated with fertility not yet identified, additional tests will be necessary, but it is clear that the 2D electrophoresis of the sperm membrane can be used for a new approach to predict Nelore bull fertility.  相似文献   

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Sperm whale oxymyoglobin was isolated directly from muscle and was examined for its stability properties over the wide range of pH 5–13 in 0.1 m buffer at 25 °C. The remarkable pH dependence for the autoxidation rate was analyzed using the kinetic equation derived in terms of nucleophilic displacement processes of O2? from oxymyoglobin by the entering water molecule or hydroxyl ion with the iron resulting in the ferric form. Most of the autoxidation reaction of the oxymyoglobin can be best explained by the proton-catalyzed processes involving the distal histidine as the catalytic residue. The kinetic equation could also be used as an interesting diagnostic probe into differences in the heme reactivity and the heme environment of different types of oxymyoglobin from other sources.  相似文献   

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Bull sperm and paramecium cilium were exposed to uniform static magnetic fields to observe their magnetic orientations and measure their anisotropic diamagnetic susceptibility (deltachi) for each. The prepared samples were whole bull sperm, bull sperm flat heads, and paramecium cilia, because bull sperm tails in a perfect condition could not be prepared. The whole bull sperm and the bull sperm heads became oriented perpendicular to the magnetic fields (1.7 Tesla maximum), while the paramecium cilia became parallel to the magnetic fields (8 Tesla maximum). A whole bull sperm, a bull sperm head, and a paramecium cilium were photometrically studied to obtain deltachi for each, which were estimated to be 1 x 10(-19), 3 x 10(-19), and 2 x 10(-20) J/T(2), respectively. deltachi of a sperm flagellum was estimated from the measured value of deltachi of the paramecium cilium, which agrees well with the difference between deltachi of the whole sperm and the sperm head. Additionally, this difference of deltachi almost coincides with the deltachi values calculated from deltachi of tubulin, as well. If the magnetic effect on biological systems is solved and the magnetic orientation correlates with it, deltachi will become the quantitative index of the effect.  相似文献   

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We have investigated an exocytotic event, the acrosome reaction (AR), induced by treatment of bovine sperm with vesicles composed of dilauroyl phosphatidylcholine (PC12). Cell membrane permeability barriers (dye exclusion), acrosomal status (pisum sativum (PSA) lectin binding), and intracellular Ca2+ (Fluo3 fluorescence) were evaluated utilizing flow cytometry and fluorescence microscopy. By these methods the AR is resolved into four kinetically distinct steps: (a) PC12 transfer to the sperm plasma membrane (PM); (b) increased permeability of the PM to extracellular Ca2+; (c) localized leakage of acrosomal contents at the anterior tip of the sperm; and (d) vesiculation of sperm membranes and complete exposure of acrosomal contents. Evidence for PC12 transfer to sperm includes transfer of a fluorescent PC12 analogue from vesicles to cells and the absence of detectable vesicle--cell fusion. The fusion inducing properties of PC12 appear to reside in the lipid head group as neither dilauroylphosphatidylethanolamine nor dilauroylphosphatidylglycerol stimulated the AR. The effect of PC chain length on AR induction closely parallels the aqueous phase solubility of the lipid tested. The rate and extent of the AR depend on the extracellular calcium concentration. Cells treated in the absence of calcium do not undergo the AR, but do so rapidly (less than 1 min) upon subsequent addition of calcium. This role of Ca2+ is partially filled by Sr2+, but not by Ba2+ or Mg2+. The rate of the AR decreases with decreasing temperature and the AR occurs very slowly below 27 degrees C. Simultaneous evaluation of intracellular calcium and acrosomal status reveals the kinetic relationship between Ca2+ influx and the exposure of acrosomal contents. N-Ethylmaleimide preincubation arrests PC12-treated sperm at an intermediate stage in the AR, characterized by punctate PSA binding over the tip of the sperm head. The AR, a developmentally regulated, receptor-mediated fusion event, synchronously induced here in vitro, provides a useful model for mechanistic studies of exocytosis.  相似文献   

12.
Cryopreservation induces an apoptosis-like mechanism in bull sperm   总被引:8,自引:0,他引:8  
Cryopreservation induces many changes in sperm cells, including membrane disorders and cell death. We tested the hypothesis that apoptosis, a form of programmed cell death, can contribute to the fatal effect of cryopreservation on sperm cells. A multiparametric study of apoptosis on bovine sperm is proposed, using flow cytometry, including mitochondrial membrane potential (DeltaPsi(m)), caspase activation, membrane permeability, nucleus condensation, DNA fragmentation, and phosphatidylserine (PS) externalization. The relevance of each test was first validated on a human somatic cell line, U937. Cryopreservation and/or thawing induced significant changes in all apoptotic markers in living bull sperm cells except those concerning the nucleus. After cryopreservation, 44.9% +/- 17% (vs. 11.3% +/- 10.6% before cryopreservation) of sperm cells showed low DeltaPsi(m), 12% +/- 6.3% (vs. 2.2% +/- 1.0% before) contained active caspases, and 10.8% +/- 5.8% (vs. 1.4% +/- 1.1% before) exhibited high membrane permeability. However, cryopreservation had no effect on DNA fragmentation (9.1% +/- 7.7% before vs. 11.1% +/- 5.7% after cryopreservation) or on nucleus condensation (46% +/- 12.7% before vs. 43.8% +/- 13.1% after). Cryopreservation acts as an apoptotic mechanism inducer in bovine sperm cells, where the earliest but not the latest features of cells undergoing apoptosis occur. We have named this abortive process an apoptosis-like phenomenon.  相似文献   

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A Simmental bull with a history of low fertility, both by natural service and artificial insemination, was presented for examination. Two previous semen evaluations had revealed no specific semen abnormalities that would support the breeding history. A comprehensive cytochemical analysis of the bull's ejaculate revealed a complex nuclear lesion affecting over 80% of sperm. This condition was expressed in abnormal shaping of the nuclei, with deficient distribution, condensation and stabilization of the nucleoplasm. These abnormalities were associated with various-sized intranuclear pouches or depressions. The acrosome was moderately involved and the tail was relatively free of abnormalities resulting in normal sperm motility.Two controlled breeding trials utilizing a total of 15 super-ovulated females were conducted to evaluate the bull's fertilization rate. Combined data demonstrated an 18% (23128) fertilization rate of recovered ova. At the same time, the fertilization rate of seven bulls classified as satisfactory potential breeders was 72% (353490).Data from two embryo transplant units regarding ova collected from eight donor females inseminated with semen from this bull revealed a fertilization rate of 41% (3073). Of the fertilized ova, 37% (1130) were degenerate and were not transferred. A pregnancy rate of 57% (1119) resulted from the transfer of 19 fertilized ova.A natural breeding pregnancy rate of 5% (242) and artificial breeding pregnancy rate of 8% (15180) support the breeding trial results.  相似文献   

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Luteinizing hormone was extracted from sperm whale pituitaries and separated into alpha- and beta-subunits. These subunits were cleaved with cyanogen bromide, and digested with trypsin and chymotrypsin. The fragments obtained were separated and purified by gel filtration on Sephadex and by ion exchange chromatography, reversed phase chromatography and chromatoelectrophoresis. The amino acid sequence of peptides obtained was studied by dansyl-Edman's method and Edman's modification of Chang et al. The study made it possible to establish the complete amino acid sequence of sperm whale LH alpha- and beta-subunits.  相似文献   

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The sperm cells in the tricellular pollen grains ofCircuta virosa, Bupleurum subovatum, andApium nodiflorum differ significantly from sperm cells known so far. They are extremely destitute of plasma. Besides the sperm nucleus, no cytoplasmic organelles are observed. The wall of the sperm cell forms long, slender projections on both poles of the spindle-shaped cell.  相似文献   

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Massive urolithiasis of the penile urethra was observed in an adult pygmy sperm whale (Kogia breviceps) stranded on Topsail Island, North Carolina, USA. Calculi occupied the urethra from just distal to the sigmoid flexure to the tip of the penis for a length of 43 cm. A urethral diverticulum was present proximal to the calculi. The major portion of the multinodular urolith weighed 208 g and was 16 cm long x 3.7 cm diameter at the widest point. The urolith was composed of 100% struvite (magnesium ammonium phosphate) and on culture yielded Klebsiella oxytoca, a urease-positive bacterium occasionally associated with struvite urolith formation in domestic animals. Reaction to the calculi was characterized histologically by moderate multifocal to coalescing plasmacytic balanitis and penile urethritis. Role of the urethrolithiasis in the whale's stranding is speculative but could have involved pain or metabolic perturbations such as uremia or hyperammonemia.  相似文献   

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The first known case in the United States of a bull with the sterilizing oligoteratozoospermia known as “sperm tail stump defect” is reported. Ejaculates of semen were characterized by a watery appearance, extremely low sperm concentrations, sperm akinesia, and 100% abnormal spermatozoa. Different degrees of partial tail development were observed. The most common abnormalities were a short midpiece remnant or a cytoplasmic droplet-like rounded body replacing the midpiece and tail. Also, a high percentage of sperm head abnormalities were found. Testicular histology revealed seminiferous tubules with a low rate of spermatogenesis. Elongation of the spermatids did not proceed normally and no normal tail development was observed.  相似文献   

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When isolated bull sperm chromatin is incubated with 0.1 M 2-mercaptoethanol at pH 8, an extensive proteolytic degradation of sperm histone occurs, being accompanied by a marked swelling of the chromatin masses. The degradation of sperm histone is strongly inhibited by monovalent or divalent metal ions. The protease found in isolated bull sperm chromatin possesses properties indistinguishable from those of an acrosomal protease of trypsin-type, acrosin (EC 3.4.21.10), and requires a combination of NaCl, urea and 2-mercaptoethanol for its extraction. Evidence suggests that the protease travels along chromatin strands and hydrolyzes essentially all the sperm histone molecules within the chromatin masses.  相似文献   

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