摘要:

SummaryCapacitation of human spermatozoa is essential for fertilization, and is characterized visually by hyperactivated motility. We have investigated whether reactive oxygen species could induce these two events in human spermatozoa. The addition of xanthine + xanthine oxidase + catalase (X+XO+CAT: generation of superoxide anion and removal of hydrogen peroxide) and foetal cord serum (FCS), a known biological inducer of capacitation and hyperactivation, to spermatozoa, induced levels of hyperactivation (15.4 ± 1.6% and 8.0 ± 1.0%, respectively) which were significantly higher than that of controls (5.4 ± 0.6%). The hyperactivation measured was part of the capacitation process. Furthermore, the addition of superoxide dismutase prevented the capacitation and hyperactivation induced by X+XO+CAT or by FCS. These results suggest that the superoxide anion may be involved in capacitation and hyperactivation of human spermatoz

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01148.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01376.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SUMMARYIn EnglishThese studies were initiated by the results of two Danish investigations of infertility clients, which indicated the reduced fecundity of male metal welders. The objective was to refute or corroborate the effects of welding on male reproductive capability and — if there was any effect — to identify the causal exposures. The initial hypothesis postulated reduced spermatogenesis, spontaneous abortion, congenital malformation and childhood malignancy following exposure to hexavalent chromium among stainless steel welders. Subsequently, a hypothesis concerned with the significance of exposure to radiant heat on reduced semen quality was put forward. These studies comprised a case‐referent study of infertility, cross‐sectional and longitudinal studies of semen quality and historical cohort studies of fertility, pregnancy outcome and cancer in offspring.Exposure to welding was reported with a higher frequency during periods of infertility than prior to conception in the case‐referent study (OR 2.0,95% CI 1.0–4.0). This finding is consistent with the main cross‐sectional study showing reduced semen quality in welders [average reduction ranging from 8% (sperm penetration rate in eggwhite) to 28% (total sperm count)] and with the cohort study revealing reduced fertility in relation to welding (OR 0.89, 95% CI 0.83‐0.97). However, reduced semen quality and fertility were not attributable to the welding of stainless steel but to the welding of mild steel; and no relationship was found between biological measures of exposure to chromium and parameters of semen quality. If the unexpected association between mild steel welding and reduced fecundity is causal, the biological mechanisms involved are obscure. A separate longitudinal study leaves little doubt that moderate radiant heat exposure may cause reversible deterioration of semen quality, but it is not justified to generalize this observation to the entire population of welders. Male‐mediated effects on occurrence of congenital malformation and cancer in offspring from stainless steel welding are not indicated by the studies. Weak indications of an increased risk of spontaneous abortion among partners to stainless steel welders (OR 1.9, 95% CI 1.1–3.2) need to be refuted or corroborated in future studies.Suggested effects of mild steel welding on male fecundity should be corroborated by longitudinal controlled studies of semen quality examined before and during exposure and by prospective studies of fecundability in couples trying to conceive a child. On account of the present knowledge it is not possible to recommend rational preventative measures with the exception of elimination of radiant heat exposure in cases of infertility. Temporary transfer to jobs not involving welding work should be considered when cases of unexplained infertility are encountered in clinical practice.In DanishDe foreliggende undersøgelser blev igangsat som konsekvens af to danske infertilitetsstudier, som fandt nedsat fekunditet blandt metalsvejsere. Formålet var at be‐ eller afkræfte sammenhæng mellem svejsning og nedsat mandlig forplantningsevne og i givet fald at identificere årsagerne. En á priori hypotese postulerede påvirket spermatogenese samt spontan abort, kongenit malformation og bo̊rnecancer som følge af udsættelse for hexavalent krom ved svejsning på rustfrit stål. I undersøgelsesforløbet fremsattes herudover en hypotese om nedsat sædkvalitet forårsaget af eksponering for strålevarme ved svejsning på forvarmet stål. Undersøgelserne omfatter en case‐referent undersøgelse af ufrivillig barnløshed, tværsnits‐ og forløbsundersøgelser af sædkvalitet og kønshormoner samt historiske kohortestudier affertilitet, negative graviditetsudfald og børnecancer.Svejsearbejde rapporteredes hyppigere ved infertilitet end forud for konception i case‐referent undersøgelsen (OR 2.0, 95% CI 1.0–4.0). I overensstemmelse hermed fandtes nedsat sædkvalitet blandt svejsere i tværsnitsundersøgelsen (gennemsnitlig reduktion fra 8% (penetration i æggehvide) til 28% (totalt sædcelle antal)) samt nedsat fertilitet i tilslutning til svejsearbejde i kohorteundersøgelsen (OR 0.89, 95% CI 0.83‐0.97). Nedsat sædkvalitet og fertilitet var dog ikke relateret til svejsning på rustfrit stål, men til svejsning på almindeligt konstruktionsstål (sort jern) og der fandtes ingen relation mellem biologiske møl for kromeksponering og sædkvalitetsparametre. Såfremt den uventede relation mellem svejsning på konstruktionsstål og nedsat fekunditet er udtryk for en kausal sammenhæng, er det uklart, hvilke biologiske mekanismer, der er involveret. En særskilt longitudinel sædkvalitetsundersøgelse taler overbevisende for, at en moderat udsættelse for strålevarme kan medfo̊re en forbigående nedsættelse af sædkvalitet, men dette fund kan ikke generaliseres til almindeligt svejsearbejde. Der fandtes ingen holdepunkter for, at svejsning på rustfrit stål øger forekomsten af kongenit malformation og børnekræft via mandligt medierede mekanismer. Spontan abort forekom hyppigere blandt partnere til rustfrit stål svejsere (OR 1.9, 95% CI 1.1–3.2), men dette fund kan ikke tillægges betydning med mindre det kan reproduceres med anden undersøgelsesteknik.Den fundne sammenhæng mellem svejsning på almindeligt konstruktionsstål og nedsat mandlig fekunditet bør bekræftes ved longitudinelle kontrollerede undersøgelser af sædkvalitet før og under eksponering eller ved prospektive studier af fekundabilitet blandt par, som forsøger at få børn. På grundlag af de foreliggende undersógelser er det desværre ikke muligt at at anbefale rationelle forebyggende foranstaltninger bortset fra eliminering af udsættelse for st

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01377.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01378.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SummaryAn in‐vitro method was developed to study Sertoli—Leydig cell interactions in man, using testes removed at the time kidneys were removed for transplantation from 6 young adult men (aged 17–45 years) after cerebral death. After collagen‐ase digestion of testicular tissue, Leydig cells were purified on discontinuous Percoll gradients. Two fractions of Leydig cells, ‘L2’ and ‘L3’ which differed in their buoyant density (1.05 g

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01149.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SummarySteroid regimens containing androgens are being evaluated currently as hormonal contraceptives for men. The possible non‐reproductive effects of such treatment were assessed during an efficacy trial using a prototype regime of 200 mg testosterone enanthate i.m. weekly. Prostatic function and size were monitored by regular rectal examination, blood levels of prostate‐specific androgen (PSA) were measured in 30 men and prostatic size was measured by trans‐rectal ultrasound imaging in a representative subgroup of five subjects for 12 months and for a further 6 months after discontinuation. Despite the sustained rise in serum levels of testosterone, oestradiol and dihydrotestosterone during treatment, there was no detectable increase in prostatic size on rectal examination or any significant change in blood concentrations of PSA. A small but significant increase (14.3 ± 2.0%) in maximal prostate transverse area was observed in four men while the remaining one showed no change. Our preliminary data demonstrate the feasibility and importance of monitoring prostatic function in the development of androgen‐containing male hormonal contra

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01150.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SummarySecretions were collected from the ampullary gland, dorsolateral prostate, ventral prostate, coagulating glands and seminal vesicles of male golden hamsters aged 15–20 weeks. The concentrations of total protein, citric acid, fructose, acid phosphatase, chloride, sodium, potassium, calcium, magnesium and zinc were determined. The ampullary gland secreted predominantly citric acid, sodium and acid phosphatase. Zinc was secreted only by the prostatic complex, with the largest quantity coming from the coagulating gland. The highest concentrations of potassium, calcium and magnesium were found in secretions of the ventral prostate. The coagulating gland and dorsolateral prostate were the principal contributors to total protein. The hamster appears to be more related to the mouse than to the rat in terms of the secretory functions of its accessory sex gland

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01151.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SummaryEpididymitis was induced by retrograde injection ofEscherichia coliinto the vas deferens of 28 mice. A group of 28 saline‐injected animals served as controls. On Days 1, 3, 7 and 28, groups of seven animals were killed. Bacterial culture was performed. Leucocyte numbers and distribution were determined in epididymides.In infected mice,E. coliwere isolated from all epididymides on Days 1 and 3, but only from five of seven epididymides on Days 7 and 28. One week after infection, the total number of macrophages rose from about 10 to 28%. Significantly increased macrophage percentages were also found in animals killed 28 days after infection. A simultaneous increase in MHC class II positive cells was seen on Day 7. A total of 20% of the cells expressed MHC class II in infected epididymides (normal = 6%). A similar increase was found on Day 28 after infection. Most of the macrophages and MHC class II positive cells were located in the interstitium, fewer in the peritubular layer and nearly none in the epithelium. The main increase in these cells occurred in the interstitium and, to a lesser but significant extent, in the peritubular area.T‐helper and T‐suppressor/cytotoxic lymphocytes reached peak values on Day 28. The increase in T‐lymphocytes and simultaneous appearance of plasma cells follo wed the increase in numbers of macrophages and MHC class II positive cells. They were located mainly in the interstitium. A sequential increase in leucocyte subsets and negative culture results forE. coliwere observed on Days 7 and 28 (2/7 on each day). The inflammatory process was restricted to the interstitium.It is concluded that stimulation of T‐lymphocytes and plasma cells by macrophages/MHC class II positive cells acts as an effective immune response toE. coliin the epididymal inte

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01152.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SummarycDNA probes derived from genes expressed specifically in the human epididymis were used to examine gene expression in the epididymides of boar, bull and stallion by Northern hybridization. Two probes for the HE1 and HE4 gene products were found to recognize tissue‐specific transcripts in all three species, with a regionally differential distribution within the epididymis. Additionally, antibodies recognizing the HE4 protein were shown to react specifically in the epididymis of the boar and bull. An extensive study of the boar showed that, whereas mRNA for the HEl‐homologue was up‐regulated markedly only at puberty, the HE4‐homologue was already present at moderate levels prepubertally. The distribution of the HEl‐homologue changed at sexual maturity from a maximum in the cauda epididymis in the 3–4‐week‐old pig, to a maximum in the corpus/caput region in the adult, while the shift was in the opposite direction for the HE4‐homologue. Evidently, gene expression is not fixed regionally through epididymal development in this species. The abdominal epididymis of a hemicryptorchid pig also showed a differential change in expression for the two gene products by comparison with the scrotal testis from the same animal. The results suggest that the HE1 and HE4 gene homologues may be sensitive markers for physiological changes within the mammalian epididymis, and that the boar could prove a useful model to examine the regulation of these human epidi

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01153.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SummaryAdult unilaterally cryptorchid rats were injected with 50 IU human chorionic gonadotrophin (hCG). At 4, 8, 24 and 72 h after treatment, testicular vascular permeability was studied by injecting colloidal carbon intravenously. The number of blood vessel profiles labelled with carbon was increased by hCG in both types of testes, but the response was more sustained in abdominal than in scrotal testes. The number of polymorphonuclear leucocytes (PMNs) accumulating in testicular blood vessels and migrating into the interstitial space in response to hCG treatment was also measured. The volume density of intravascular and interstitial PMNs was increased in both types of testes but the peak response was larger in scrotal than in abdominal testes. PMN accumulation and vascular leakage were apparently correlated in the scrotal but not in the abdominal testes.Testicular interstitial fluid (IF) was collected from intact and unilaterally cryptorchid adult rats. The IF was diluted with sterile buffer and injected intracutaneously in test animals. The vascular permeability response was assessed by measuring the leakage of Evans blue into the injection sites. IF from scrotal and abdominal testes increased vascular permeability in the skin. The response was rapid and transient. IF collected from rats given hCG 24 h earlier did not increase vascular permeability. The vascular permeability response to IF was reduced slightly in neutrophil‐depleted animals. The inflammation mediator present in IF cannot explain the kinetics and magnitude of the hCG‐induced changes in vascular premeability in intact or unilaterally cryptorchid r

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01154.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY