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1.
Seminal plasma separated from freshly ejaculated bull semen contains vesicles with a 5-nucleotidase activity incorporated as an ectoenzyme anchored by glycosyl phosphatidylinositol (GPI). After its extraction from bull seminal plasma vesicles, the protein was purified and reconstituted into hen egg yolk lecithin liposomes obtained through prolonged dialysis of buffered n-octylglucoside detergent solutions of lipid, protein and various effectors against detergent-free solutions. Gel filtration experiments showed that the enzyme incorporated into liposomes in a dimeric form with its two subunits linked by disulfide bridges. In the presence of reduced glutathione, the protein dissociated into monomers and failed to incorporate into liposomes. Electron spin resonance (ESR) experiments, performed with liposomes containing electron spin labels localized at the hydrophilic lipid headgroups (5-doxyl stearic acid) or in the hydrophobic lipid hydrocarbon chains (16-doxyl stearic acid), demonstrated that the incorporation of 5-nucleotidase resulted in the immobilization of the spin probes. Furthermore, the spectral parameters obtained before and after treatment of 5-nucleotidase-containing liposomes with phosphatidylinositol-specific phospholipase C (PI-PLC) indicated that the liposome membrane bilayer did not contain protein segments. This supports the well-known ecto-localization of 5-nucleotidase and rules out a previously reported possibility of a proteic transmembrane anchoring of the enzyme.We thank Mr. Marcello Coli and Dr. Maria Grazia Cantelmi, University of Perugia, for their skillful technical assistance; Dr. Paolo Ghinassi and Dr. Franca Farabegoli, Semen Italy, Diegaro, Cesena, Italy and Dr. Augusto Chiacchierini, Centro Tori Perugia, Italy, for kindly supplying the bull semen; Dr. Maria Grazia Rambotti, Department of Experimental Medicine, University of Perugia, Italy, for her skillful assistance in the electron microscopy experiments; Ms. Darlene I. Morosi for her helpful suggestions.  相似文献   

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Summary After testing a population sample of 185 hospitalized Italian children for the plasma -L-fucosidase deficiency and establishing an approximate threshold value between heterozygotes and wild-type homozygotes, we analyzed by two statistical methods the distribution of the two genotypes. The results obtained by probit analysis agree with threshold and average values expected on the basis of the Hardy-Weinberg equilibrium.In addition, the level of -fucosidase in leukocytes of 12 individuals with deficiency of -fucosidase in plasma was found to be significantly lower than that of 61 controls (P<0.005). These results indicate that the mutation(s) causing a deficiency of -fucosidase in plasma is (are) also expressed in leukocytes.  相似文献   

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  • 1.1. Starch gel electrophoresis was carried out on the non-specific esterases in bull seminal plasma.
  • 2.2. Differentiation of non-specific esterases was performed by using different substrates and inhibitors.
  • 3.3. It is suggested that the non-specific esterases in bull seminal plasma belong to the types A, B, C.
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Planarians have a remarkable capacity for regeneration after ablation, and they reproduce asexually by fission. However, some planarians can also reproduce and maintain their sexual organs. During the regenerative process, their existing sexual organs degenerate and new ones develop. However, little is known about hormonal regulation during the development of reproductive organs in planarians. In this study, we investigated the effects of 17β-estradiol (a steroid) and bisphenol A (an endocrine disrupter) on the formation of sexual organs in the hermaphroditic planarian Dugesia ryukyuensis. Under control conditions, all worm tissues regenerated into sexual planarians with sexual organs within 4 weeks after ablation. However, in the presence of bisphenol A or 17β-estradiol, although they apparently regenerated into sexual planarians, the yolk glands, which are one of the female sexual organs, failed to regenerate even 7 weeks after ablation. These data suggest that planarians have a steroid hormone system, which plays a key role in the formation and maturation of sexual organs.  相似文献   

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In the present study we examined the effect of seminal plasma (SP) on angiogenesis in the porcine oviduct. Gene expressions of vascular endothelial growth factor (VEGF) and its two receptors (Flt-1: fms-like tyrosine kinase and Flk-1/KDR: fetal liver kinase-1/kinase insert domain-containing receptor) as well as fibroblast growth factors (FGF-1 and 2) and von Willenbrand factor (VWF) were determined in the oviduct of SP-treated and control (PBS-treated) gilts. Moreover, vascular density (VD) indicated by endothelial cell area immunolocalized by VWF staining, was assessed in the oviducts. Real-time PCR revealed significantly higher expression of FGF-2 and VWF on day 1 (p < 0.05) after SP administration in comparison to control animals. In contrast, Flt-1 mRNA level on day 1 was lower in SP-treated gilts compared to controls (p < 0.05). In the examined oviductal sections, VD did not differ between control and SP-treated animals. However, in SP-treated animals VD was higher on day 5 than on day 1 (p < 0.05) or 3 (p < 0.01). SP had no significant effect on VEGF, Flk-1/KDR and FGF-1 mRNA expression. In conclusion, our results suggest that SP affects the vascular network by changing the expression of factors contributing to angiogenesis.  相似文献   

8.
Reproductive units (RUs) of Trithuria, the sole genus of the early-divergent angiosperm family Hydatellaceae, are compared with flowers of their close relatives in Cabombaceae (Nymphaeales). Trithuria RUs combine features of flowers and inflorescences. They differ from typical flowers in possessing an "inside-out" morphology, with carpels surrounding stamens; furthermore, carpels develop centrifugally, in contrast to centripetal or simultaneous development in typical flowers. Trithuria RUs could be interpreted as pseudanthia of two or more cymose partial inflorescences enclosed within an involucre, but the bractlike involucral phyllomes do not subtend partial inflorescences and hence collectively resemble a typical perianth. Teratological forms of T. submersa indicate a tendency to fasciation and demonstrate that the inside-out structure-the primary feature that separates RUs of Hydatellaceae from more orthodox angiosperm flowers-can be at least partially modified, thus producing a morphology that is closer to an orthodox flower. The Trithuria RU could be described as a "nonflower", i.e., a structure that contains typical angiosperm carpels and stamens but does not allow recognition of a typical angiosperm flower. The term nonflower could combine cases of secondary loss of flower identity and cases of a prefloral condition, similar to those that gave rise to the angiosperm flower. Nonhomology among some angiosperm flowers could be due to iterative shifts between nonfloral construction and flower/inflorescence organization of reproductive organs. Potential testing of these hypotheses using evolutionary-developmental genetics is explored using preliminary data from immunolocalization of the floral meristem identity gene LEAFY in T. submersa, which indicated protein expression at different hierarchical levels.  相似文献   

9.
Opisthorchis viverrini infection induces inflammation-mediated oxidative stress and liver injury, which may alter α-tocopherol and lipid metabolism. We investigated plasma α-tocopherol and lipid profiles in hamsters infected with O. viverrini. Levels of α-tocopherol, cholesterol, and low-density lipoprotein increased in the acute phase of infection. In the chronic phase, α-tocopherol decreased, while triglyceride and very low-density lipoprotein increased. Notably, high-density lipoprotein decreased both in the acute and chronic phases. In the liver, cholesteryl oleate, triolein, and oleic acid decreased in the acute phase, and increased in the chronic phase. Such chronological changes were negatively correlated with the plasma α-tocopherol level. The expression of α-tocopherol-related molecules, ATP-binding cassette transporter A1 (ABCA1) and α-tocopherol transfer protein, increased throughout the experiment. These results suggest that O. viverrini infection profoundly affects on lipid and α-tocopherol metabolism in due course of infection.  相似文献   

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The objectives of this study were (1) to determine the effect of rabbit seminal plasma on LH secretion and ovulation using the llama animal model as an in vivo ovulation bioassay and (2) to determine the effect of llama or rabbit seminal plasma on ovulation induction in the rabbit model. In Experiment 1, llamas with a growing follicle ≥8mm in diameter were assigned randomly to one of three groups (n=5 per group) and given an intramuscular dose of 1mL of: (a) llama seminal plasma, (b) rabbit seminal plasma, or (c) phosphate buffered saline (PBS; negative control). Blood samples for LH measurement were taken every 15 min from 1.5 h before to 8 h after treatment (Day 0: starting of treatment). Llamas were examined by ultrasonography every 12h from treatment to ovulation, and then every other day until Day 16 after treatment to evaluate corpus luteum (CL) development. Blood samples for progesterone measurement were taken every other day from Day 0 to Day 16. Ovulation was detected in 4 of 5, 5 of 5, and 0 of 0 llamas treated with llama or rabbit seminal plasma and PBS, respectively (P<0.001). After treatment, plasma LH concentration increased and decreased (P<0.01) in the llama and rabbit seminal plasma group but not in the PBS-treated group. No differences were observed on CL development (P≥0.3) and progesterone secretion (P>0.05) between both seminal plasma treated groups. In Experiment 2, receptive female rabbits (n=5-7 per group) were given an intramuscular dose of: (a) 0.5, (b) 1.0 and (c) 2.0mL of either rabbit or llama seminal plasma, (d) 0.5mL PBS (negative control), or (e) 25μg of gonadoreline acetate (GnRH; positive control). Does were submitted to laparotomy 24-36 h after treatment to determine the ovulatory response and the presence of antral and hemorrhagic anovulatory follicles. Ovulation sites (7.0±0.6) were only detected in GnRH-treated does (P<0.01). There was an increase (P<0.01), in the total number of follicles (antral plus hemorraghic follicles) in those females treated with 1mL of rabbit seminal plasma and there was a tendency (P=0.08) for more hemorrhagic anovulatory follicles in does treated with 1.0 and 2.0mL of either rabbit or llama seminal plasma. Results document the presence of OIF in the seminal plasma of rabbits. The differential ovulatory response between species, however, requires further investigation.  相似文献   

13.
Summary Alpha D-mannosidase activity in goat semen was observed to be distributed in sperm and seminal plasma. In sperm the enzyme, present in soluble and bound forms, was located within the acrosome. The bound enzyme was associated with the denuded sperm. Seminal plasma -mannosidase was purified 100-fold and the final preparation was shown to be homogeneous by polyacrylamide and SDS gel electrophoresis and on isoelectric focusing. The molecular weight of the enzyme, determined by gel filtration and disc electrophoresis in the presence of SDS, was 220,000. The isoelectric pH was 7.42 and the amino acid composition is reported.-Mannosidase catalyzed the hydrolysis of both synthetic and natural substrates. The Km of p-nitrophenyl -D-mannoside and -methyl D-mannoside were 0.695 mm and 71.9 mm at pH 4.0, the optimum pH. The natural substrates were hydrolysed to varying degrees. Zn2+ was not essential though it activated the enzyme activity over longer incubations. The enzyme was observed to be more stable at wider pH range in the presence of Zn2+ than in its absence. EDTA which did not affect the enzyme activity has effect on enzyme stability similar to Zn.2+ Seminal -mannosidase is not a zinc metalloenzyme but is activated by Zn2+.NDRI-publication no. 77-145.  相似文献   

14.
Fucosidosis is an autosomal recessive lysosomal storage disease due to a deficiency of-L-fucosidase activity in tissues and body fluids. Exponentially growing lymphoid cell cultures from four fucosidosis patients had 2.7-fold to 15.6-fold less extracellular-L-fucosidase protein and 28.8-fold to 144.0-fold less intracellular-L-fucosidase protein with negligible catalytic activity, compared to the mean of 19 control cultures. The percentage of total-L-fucosidase protein released extracellularly by cultures from the four patients was 64 to 85%, compared to 35±9% for control cultures. Intracellular and extracellular enzyme forms in fucosidosis and control cell lines were glycoproteins containing polypeptide chains ofM r=52,000. During a 1.5-hr pulse-label with35S-methionine,-L-fucosidase was synthesized by control cells and two fucosidosis cell lines as an intracellular form withM r=58,000. During a subsequent 21-hr chase with unlabeled methionine, mutant enzyme was almost entirely processed to an extracellular form withM r=62,000. In contrast, only 25–30% of control enzyme was processed to an extracellular form (M r=62,000), with the remainder retained intracellularly (M r=60,000). In the other two fucosidosis cell lines,-L-fucosidase was synthesized as an intracellular form withM r=56,000 that was processed to an extracellular form withM r=60,000. In summary, the fucosidosis mutation(s) affected the catalytic activity, quantity, and extracellular release of-L-fucosidase as expressed by lymphoid cells.This work was funded by NIH Grants DK 32161 to R. A. DiCioccio and GM 28428 to J. K. Darby.  相似文献   

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Summary During immunocytochemical investigations on the presence of opioid peptides in gastrointestinal endocrine cells it was found that a subpopulation of plasma cells located in the lamina propria of the canine colonic mucosa showed immunoreactivities for -endorphin. All immunohistochemical specificity controls proved the specificity of the reaction. Circumstantial evidence suggest, however, that no authentic -endorphin is present within this cell type. Possibly sequence homologies between -endorphin and the amino acid composition of a certain immunoglobulin are responsible for the immunocytochemically specific -endorphin-like immunoreactivity of plasma cells.Supported by a grant from the Deutsche Forschungsgemeinschaft, SFB 87/G 2  相似文献   

17.
 The reproductive organs of the simultaneous hermaphrodite Sphaerosyllis hermaphrodita (Syllidae, Exogoninae) were examined by TEM and reconstructed from ultrathin serial sections. Oocytes are produced in the 11–13th chaetigerous segments and then attached to the outer body surface. The male organs comprise a seminal vesicle, testes, sperm ducts and copulatory chaetae. The unpaired seminal vesicle is an uncompartmented cavity above the gut and within the chaetigerous segments 8–10. Its interior is lined with a layer of gland cells that degenerate as spermatogenesis in the vesicle proceeds. The testes are situated ventrolaterally, close to the seminal vesicle in the 9th chaetigerous segment. They contain cells at early stages of spermatogenesis, which are connected to one another by zonulae collares. The testes and seminal vesicle are enclosed in epithelia. Paired sperm ducts run ventrally from about the midline of the body under the seminal vesicle and into the parapodia of the 9th chaetigerous segment. There they open, together with the protonephridia of this segment, to the outside next to the stout copulatory chaeta. Each sperm duct consists of six cells, the luminal surface of which bears microvilli but no cilia. Only in animals with fully differentiated sperm does the small opening of the proximal duct cell in each duct give access to the seminal vesicle. The mode of sperm transfer is discussed. Accepted: 9 December 1996  相似文献   

18.
Summary Exercise induces significant changes in the free intracellular amino acid pool in skeletal muscle but little is known of whether such changes also occur in cardiac muscle. In this study the effect of regular exercise on the size and the constituents of the free amino acid pool in the hearts and in the plasma of thoroughbred horses was investigated. The total free intracellular amino acid pool in the hearts of control horses was 30.9 ± 1.2mol/g wet weight (n = 6). Glutamine but not taurine was present at the highest concentration (13.5 ± 0.9 and 7.7 ± 0.69mol/g wet weight for glutamine and taurine respectively). As for the rest of the amino acids in the pool, only glutamate and alanine were present at levels greater than 1mol/g wet weight (4.6 ± 0.25 and 1.7 ± 0.14 for glutamate and alanine respectively). The tissue to plasma ratio was highest for taurine at 155, followed by glutamate at 111, aspartate and glutamine at 37, alanine at 5.8 and ratios of less than 3 for the rest of the amino acids. The total free intracellular amino acid pool in the hearts of exercised horses was slightly but not significantly lower than control (28.1 ±1.1mol/g wet weight, n = 6). Regular exercise increased the intracellular concentration of threonine, valine, isoleucine, leucine and phenylalanine but was only significant (p < 0.05) for threonine. This work has documented the profile of taurine and protein amino acids in the heart and in the plasma of thoroughbred horses and showed that in contrast to skeletal muscle, heart muscle does not show major changes in amino acids during regular exercise.  相似文献   

19.
Oxidative stress is associated with many disease states including gynecologic disease. This process can damage lipids, proteins and DNA. The present study highlights the role of oxidative stress induced DNA damage as measured by 8-hydroxy-2-deoxyguanosine in development of benign gynecological conditions (BGC). Our aim was to map the oxidative DNA damage on female reproductive organs and highlight the high amount found in a variety of benign gynecologic disorders. Seventeen biopsy specimens from female pelvic organs were divided in two groups: healthy organs tissue and BGC tissue. Healthy organs biopsy tissue included the cervix, tubes, uterus, peritoneum, and topic endometrium in secretory phase. Benign gynecological biopsy tissue included hydrosalpinges, leiomyoma, adenomyosis and tubal cysts. Immunohistochemical staining showed significantly higher levels of DNA damage between BGC and healthy organs [19.36 % (6.20; 32.51) vs. 4.61 % (0.63; 8.53); P < 0.0344]. Our results highlight the involvement of oxidative stress DNA damage in female benign pelvic disease. Hydrosalpinges, leiomyoma, and adenomyosis exhibit the highest amounts of oxidative DNA damage in the pelvic cavity.  相似文献   

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