ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02791.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Summary.Local control of Leydig cell morphology and function by seminiferous tubules was suggested in previousin vivostudies, especially those that used experimental cryptorchid rat testis as a model. These studies reported changes in morphology, increases in cell number and mitotic index and decreases in testosterone formation and luteinizing hormone/human chorionic gonadotropin receptor levels of Leydig cells. However, little is known about how these changes are mediated. We recently observed that a novel Sertoli cell‐secreted mitogenic factor stimulated proliferation, decreased testosterone formation and luteinizing hormone/human chorionic gonadotropin receptor levels, and dramatically altered the morphology of Leydig cells in culture. In the present studies, we demonstrate that an increase in coculture temperature from 33 to 37 °C increased [3H]‐thymidine incorporation (5.6‐ vs. 19.2‐fold) and labelling index (4.3% vs. 15.8%), and accelerated proliferation (2.1‐ vs. 3.9‐fold) of cultured immature Leydig cells. In addition, testosterone formation and luteinizing hormone/human chorionic gonadotropin receptor levels of Leydig cells cocultured with Sertoli cells were further decreased following a 4°C increase in coculture temperature. This elevation in culture temperature increased both the secretion of this factor by Sertoli cells and responsiveness of Leydig cells to this factor. In addition, the presence of germ cells, especially pachytene spermatocytes, inhibited the secretion of the mitogenic factor by Sertoli cells. These temperature‐ and germ cell‐associated effects mimicked the morphological and functional changes of Leydig cells reported following experimental cryptorchidism. These observations suggest a possible role of this Sertoli cell‐secreted mitogenic factor in explaining Leydig cell changes following experime

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02792.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Summary.The method for determination of angiotensin‐converting enzyme activity in human spermatozoa and seminal plasma was developed. The number of total and active‐motile spermatozoa was shown to be lower in Chernobyl victims than in healthy donors. The specific activity of angiotensin‐converting enzyme in spermatozoa from Chernobyl victims was 12 times higher than that in donors. Similar results, although to a lesser extent, were observed in patients with chronic prostatitis. In contrast, the enzyme activity in blood serum and seminal plasma was identical for all subjects investi

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02793.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Summary.The satisfying success rates reported with intra‐cytoplasmic sperm injection (ICSI) urged clinicians and scientists to re‐address the emphasis in the management of the male factor patient towards gamete manipulation in order to circumvent the underlying problem causing fertilization failure. We have designed a study to (i) calculate the collision rate of a sperm population with the human zona pellucida, using a mathematical hypothesis and (ii) use the calculated collision rate to evaluate subsequent zona binding results obtained under hemizona assay conditions. Microdroplets were used to co‐incubate sperm and human oocytes in order to evaluate zona binding. Using microvolumes, the track followed by sperm, as well as the maximum distance travelled were employed to calculate the collision rate of sperm and zona pellucida. The sperm concentrations of swim up samples were adjusted to 4 × 106and 0.8 × 106sperm ml−1. Five separate droplets each of 20 μl containing 4 × 106sperm ml−1(80000 motile sperm) and 200 μl containing 0.8 × 106sperm ml−1(160000 motile sperm), respectively, were prepared. Both volumes were incubated for 18 h at 37°C. The mean (±SD) number of spermatozoa tightly bound to hemizona, incubated in 20 μl and 200 μl sperm droplets, was 2444±612 and 548±315, respectively (P= 0.0001). The results can be used as a guideline to calculate the optimum insemination concentration needed for a specific sperm population to ensure the maximum collisio

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02794.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Summary.Male Wistar rats were intraperitoneally injected twice with 0.4 mmol kg−1FeSO4. One, 2 and 4 days after the second Fe injection, Fe and malondialdehyde (MDA) content in testis was measured, the morphology studied by light and electron microscopy and the number of spermatids counted. After Fe injection, Fe and MDA content had increased in parallel. Light microscopic inspection on days 1 and 2 after Fe injection revealed numerous necroses in the different cell types of the germ epithelium. Four days after Fe injection, fewer alterations were found. Electron microscopic investigations revealed that some spermatids contained up to three nuclei and at least three axonemes. In some sperm tails up to 11 axonemes were found. In some midpieces two or three complexes of axonemes, outer dense fibres and mitochondria were observed. In other midpieces axonemes were absent and replaced by granular and filamentous material. The number of spermatids was reduced 4 days after Fe treatment. The increase in the number of axonemes was similar to that seen in Mg and Zn deficiency, indicating that the increase in Fe content and oxygen free radicals is the major reason for the biochemical and morphological alterations in Mg and Zn deficienc

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02795.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Summary.A study was undertaken to isolate pure human antisperm antibodies from the sera of infertile couples. One hundred infertile couples attending the Infertility and IVF Unit (Beilinson Medical Center) because of unexplained infertility were tested (both partners) for antisperm antibodies. Sixty‐eight experiments were performed with positive sera containing antisperm antibodies and normal donor sperm. These experiments were followed by experiments in order to elute pure human antisperm antibodies from the sperm surface. Three experiments were performed with human sperm which were found to be coated by antisperm antibodies, in order to directly elute these antibodies from the sperm surface. In all experiments we eluted antisperm antibodies of the IgG and IgA isotypes from the sperm surface. These antibodies were demonstrated in the eluate, in each case by either the indirect immunobead test, the radial immune diffusion assay, or the electrophoresis method. Control experiments were performed as follows: (i) normal donor sperm incubated with normal serum; (ii) normal donor sperm without serum incubation; (iii) normal donor lymphocytes incubated with serum containing antisperm antibodies; (iv) normal donor lymphocytes without serum incubation. No antisperm antibodies were obtained in any of these control experiments. Absorption and elution experiments can be used for the isolation of pure human antisperm antibodies, which may then be used for the production of anti‐idiotypic antibodies to antisperm antibodies. The anti‐idiotypic antibodies could be further utilized as antigen substitutes for the production of a contraceptive vaccine and/or for application in the treatment of spontaneous abortion and infert

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02796.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Summary.Twelve anorchid pre‐pubertal and post‐pubertal patients, aged between 8.5 and 41 years, were studied. The FSH and LH basal levels as well as their responses to Gn‐RH (100 μg i.v.) were increased and prolonged in the post‐pubertal patients. The testosterone levels were in the prepubertal range and failed to increase after HCG administration (1500 I.U. t.i.d. for 3 days).Ultrasonography of the pelvis was performed in all the patients. Computed tomography and magnetic resonance of the abdomen were also performed in 6 and 5 patients respectively. These techniques failed to show any testicular tissue. Lastly, in 4 patients, surgical exploration confirmed the absence of testicular s

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02797.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Summary.Vimentin was immunocytochemically detected using a monoclonal anti‐vimentin antibody and indirect immunogold electron microscopy. In abnormal human spermatozoa, vimentin was visualized at the level of whole acrosome, post‐acrosomal region, neck and initial segment of the mid piece. The distribution of vimentin immunoreactivity was related to a spectrum of structural defects such as large cytoplasmic droplets, binucleated spermatozoa and mitochondrial disassembly in the mid pi

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02798.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Summary.Rotation of semen after liquefaction is a standard procedure in an Andrology laboratory. During rotation under aerobic conditions the semen is exposed to oxygen. Oxygen toxicity induces lipid peroxidation which is responsible for the loss of sperm function. The generation of reactive oxygen species was significantly increased after rotation. This may have a detrimental effect on sperm function during assisted reproduction.

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02799.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

ISSN:0303-4569    

DOI:10.1111/j.1439-0272.1996.tb02800.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY