bluuebunny/crossref_metadata_2025_split huggingface dataset:
Suppressive effect of a mouse testicular extract on lymphocyte activation
Authors: EMOTO M. , NISHIKAWA F. , OKU D. , HAMURO A. , KITA E. , KASHIBA S. 
Published: May 2008

SummaryThe effect of mouse testicular extract (TE) on lymphocyte activation was investigated. TE, in the dose range 75–600 μg mi‐1, suppressed significantly the blastogenic response of splenocytes to concanavalin A (Con‐A), pokeweed mitogen (PWM), phytohaemagglutinin (PHA) and lipopolysaccharide (LPS). TE also suppressed the blastogenic response of B‐cells to LPS and of T‐cells to PHA in a dose‐dependent manner as well as suppressing the mixed lymphocyte reaction (MLR). Pretreatment of splenocytes with TE did not however, completely suppress their blastogenic response to Con‐A, when the treated cells were washed prior to culturing. Furthermore, TE did not inhibit the on‐going blastogenesis of splenocytes that had been activated already with Con‐A for 48 h. Splenocytes obtained from TE‐treated mice remained capable of responding to Con‐A stimulation, whereas they did not respond to listerial antigens when mice were immunized with Listeria monocytogenes together with TE. The effects of TE were enhanced significantly by heating to 100°C, but were resistant to pronase, RNase and DNase. These results suggest that TE affects non‐specifically the stage of lymphocyte sensitization to antigens or mitogens.
Chromatin alterations induced by freeze‐thawing influence the fertilizing ability of human sperm
Authors: ROYERE D. , HAMAMAH S. , NICOLLE J. C. , LANSAC J. 
Published: May 2008

SummaryA previous cytochemical study revealed that chromatin alterations could be induced in frozen‐thawed human sperm. In order to evaluate the biological consequences of such chromatin alterations, we evaluated the relationship between these chromatin alterations and the drastic decrease or loss of sperm fertilizing ability after freeze‐thawing. Using acridine orange staining and Feulgen‐DNA quantitative microspectrophotometry, the nuclear variables of sperm were compared using samples which had either recovered, or lost their fertilizing ability after freezing ‐thawing during artificial inseminations, despite good post‐thaw motility. There was a clear decrease in Feulgen‐DNA content and nuclear surface values in sperm which exhibited a loss of fertilizing ability. Thus freeze‐thawing may alter the DNA/nuclear protein relationships and impair the fertilizing ability of human sperm.
Total ligation of the left renal vein in the dog: an inappropriate model for varicocele
Authors: LAVEN J. S. E. , WENSING C. J. G. , MEIJER J.C. , WOLVEKAMP W. T. C. , TEERDS K. J. 
Published: May 2008

SummaryInduction of varicocele was attempted by ligation of the left renal vein (LRV) in male dogs (Group I). Before the operation and in the 4‐month post‐operative period, sperm count, sperm motility, and sperm morphology of Group I (n = 8) dogs were compared to sham operated animals (Group 11, n = 5). Furthermore, haemodynamics as well as testicular and vascular morphology were studied.In Group I, changes in diameter and consistency of the spermatic cord were temporary. Semen quality was reduced significantly during the second month after ligation of the LRV, but improved thereafter. Haemodynamic studies revealed that LRV blood pressure was increased significantly in Group I dogs. An extensive venous collateral network replaced the occluded LRV. Retrograde blood flow in the left testicular vein (LTV) was observed only in the proximal part of the LTV of Group I dogs. In Group II dogs numerous pairs of sufficient valves prevented reflux into the LTV. Histological examination revealed that spermatogenesis was not impaired and that the left pampiniform plexus had not changed. The number of Leydig cells was decreased slightly in Group I dogs.Sufficient valves in the LTV prevented formation of a permanent varicocele.
Inhibition of Sα‐reductase does not simulate the effects of androgen deprivation on porphyrin metabolism by Harderian glands from the male Syrian hamster
Authors: MENENDEZ‐PELAEZ A. , BUZZELL G. R. , REITER R. J. 
Published: May 2008

SummaryAs Sα‐reductase is involved in the metabolism of indolamines in the Harderian glands of Syrian hamsters, we have compared the effects of androgen deprivation and the administration of the potent Sα‐reductase inhibitor N, N‐diethyl‐4‐methoxy‐3‐oxo‐4‐aza‐5‐androstene‐17‐carboxamida on Harderian porphyrin metabolism. Ten days after castration, porphyrin levels had increased to 40 times the values of intact hamsters. However, the inhibition of Sa‐reductase, which resulted in a significant decrease in the weight of accessory sex glands, did not modify porphyrin concentrations within the Harderian glands. It is concluded that, contrary to the situation for indolamine metabolism, testosterone per se is the main androgen involved in the sexual differences observed in Harderian porphyrin metabolism.
Non‐specific uptake of IgG by rat epididymal tubules in vitro
Authors: YEUNG C. H. , BERGMANN M. , COOPER T. G. 
Published: May 2008

SummaryTubules isolated from the initial segment, caput and corpus regions of the rat epididymis were incubated for 4 h in medium containing rat IgG or bovine‐serum‐albumin (10 mg ml‐1) and processed for light microscopy immunocytochemistry using gold‐labelled anti‐rat IgG and silver staining or peroxidase/anti‐peroxidase techniques. Distribution of IgG was confined to the peritubular matrix only, with no detectable uptake into the epithelium or lumen. In tubules incubated with rat IgG coupled to gold particles as tracer and fixed for electron microscopy, the IgG‐gold complex failed to penetrate to the base of the epithelium. When IgG‐peroxidase conjugates were used, sparse enzyme activity was localized in small basal and apical vesicles and multivesicular bodies of the principal cells. However, this uptake could not be inhibited by the presence of a 30‐fold excess of non‐labelled IgG, and the same distribution of enzyme activity was also observed when tubules were incubated with a similar activity of horseradish peroxidase alone. These findings indicate that there is no detectable receptor‐mediated transport of IgG across the epididymal epithelium, although non‐selective transfer could occur via fluid‐phase endocytosis.
Induction of the acrosome reaction in sperm by exposure to low temperature increases their rate of fusion with zona‐free hamster oocytes
Authors: Sanchez R. , Schill W.‐B. 
Published: May 2008

SummaryThe fusion rate of human sperm with zona‐free hamster ova was investigated after induction of the acrosome reaction by exposure to a low temperature (4°C). Sperm were collected from 14 patients, and selected by the ‘swim‐up’ method. The sperm were incubated for 24 h at either room temperature (control group) or at 4°C (low temperature group), followed by additional incubation at 37°C for 3 h. The mean sperm penetration rate, number of swollen sperm heads as well as the number of sperm attached to the oocyte increased significantly after exposing sperm to low temperature. The sperm penetration rate showed a significant correlation (Spearman test, r= 0.572, n= 28, P <0.0035) with the acrosome reaction in the low temperature group. These results were associated with an increase in the rate of penetration of hamster ova observed in this study, presumably due to the increase in induction of the acrosome reaction by low temperature. Incubation of sperm at low temperature might be useful in the evaluation of so‐called false negative results in the zona‐free hamster test.
Capacitation and the acrosome reaction in sperm from men with various semen profiles montored by a chlortetracycline flrorescence assay
Authors: KHOLKUTE S. D. , MEHERJI P. , PURI C. P. 
Published: May 2008

SummarySperm obtained from groups of men with various semen profiles were incubated for 8 h in BWW medium containing human serum albumin to promote capacitation. Capacitation and the acrosome reaction were monitored by a chlortetracycline (CTC) fluorescence assay. Four distinct CTC patterns were observed on the sperm head. No significant difference was observed in the time‐course curve of these CTC patterns in sperm obtained from normozoospermic, asthenozoospermic and oligo‐zoospermic men. Spontaneous and A23187‐induced acrosome reactions were also comparable in these groups. However, in sperm obtained from teratozoospermic and polyzoospermic men, the increase in CTC pattern associated with capacitation appeared slower and sluggish. In these two groups, the induced acrosome reaction was also significantly lower when compared to that in the other three groups of men. In polyzoospermia, the spontaneous acrosome reaction was significantly lower when compared to all the other groups. Fresh sperm would not undergo the acrosome reaction following A23187 treatment. The results of this study indicate sluggish (defective) capacitation and inability of capacitated sperm to undergo induced acrosome reaction in teratozoospermic and polyzoospermic men as evaluated by the CTC method.
Testosterone increases serum 1,25–dihydroxyvitamin D and insulin‐like growth factor‐I in hypogonadal men
Authors: HAGENFELDT Y. , LINDE K. , SJÖBERG H.‐E. , ZUMKELLER W. , ARVER S. 
Published: May 2008

SummaryThe short‐term metabolic effects of testosterone treatment on circulating levels of 1,25–dihydroxyvitamin D and insulin‐like growth factor‐I (IGF‐I) were studied in 13 hypogonadal men. The study group included 11 men with Klinefelter's syndrome, with varying degree of androgen deficiency, and two men with secondary hypogonadism.Pretreatment levels of 1,25–dihydroxyvitamin D, vitamin D‐binding protein and IGF‐binding protein‐I were all within the normal range. The levels of IGF‐I were lower than normal in 5/11 of the Klinefelter patients and in one patient with GH‐deficiency. Testosterone treatment increased circulating total 1,25–dihydroxyvitamin D significantly from 75 ± 4 pmol l‐1 (mean ± SEM) to 86 ± 4 (P<0.01) and the free 1,25–dihydroxyvitamin D‐index from 1.95 ± 0.11 to 2.39 ± 0.12 (P<0.01). Serum levels of IGF‐I increased from 117 ± 22 ug/l to 143 ± 23 (P<0.01) during androgen treatment. No significant effects on levels of IGF‐binding protein‐I were seen.It is concluded that androgen therapy increases the availability of 1,25–dihydroxyvitamin D and the level of IGF‐I, which may be important links in the action of testosterone.
Testosterone production in mature scorbutic mutant rats unable to synthesize ascorbic acid
Authors: ITO Y. , TSUJI M. , TERADA N. , MIYANO M. , MORI H. 
Published: May 2008

SummaryThe effect of a deficiency of ascorbic acid (AsA) on in‐vivo testosterone production in mature male rats was investigated using a mutant strain of rats (ODS rats) unable to synthesize AsA. Male 60–day‐old rats were fed AsA‐deficient lab chow for 28 days with [ODS(+)] or without [ODS(‐)] AsA supply. The AsA levels in the liver of ODS(‐) rats were undetectable and those in the testes decreased to about 25% of those in ODS(+) rats by day 28. Plasma LH levels in ODS(‐) rats decreased to about 30% of those in ODS(+) rats by day 28. However, there were no significant differences in the plasma levels of testosterone, or in the relative weights of seminal vesicles and ventral prostates between ODS(+) and ODS(‐) rats. Plasma levels of testosterone in ODS(‐) rats after a single injection of 200 IU hCG changed similarly to that in ODS(+) rats. The metabolic clearance rate of testosterone was also the same at 60 min after an intravenous injection of [3H]testosterone in both groups. These results indicate that AsA‐deficiency in adult rats causes no significant change in basal plasma levels of testosterone or in the response to hCG, despite decreased plasma LH levels.
Deficiency in major high molecular‐weight seminal proteins in men producing poorly coagulating and alkaline liquid ejaculates
Authors: MANDAL A. , BHATTACHARYYA A. K. 
Published: May 2008

SummaryUsing SDS‐PAGE three major high molecular‐weight coagulum proteins (57, 75 and 79 kD) were identified in unliquefied human ejaculates. Washed coagulum was prepared at pH 4.5 and demonstrated negligible proteolysis as determined by a highly sensitive fluorescamine‐based method. Laser densitometric scanning of these high molecular‐weight proteins in unliquefied ejaculates in relation to their coagulational failure revealed that the total content of 57, 75 and 79 kD proteins in whole semen represented ˜ 44% of levels in the normally coagulated, ˜ 24% in poorly coagulated (P<0.005) and ˜ 3% in the non‐coagulated (alkaline liquid, P<0.001) samples. The findings imply that these predominant high molecular‐weight proteins play a major role in human seminal coagulum formation.
Sperm nuclear instability and staining with aniline blue: abnormal persistance of histones in spermatozoa in infertile men
Authors: FORESTA C. , ZORZI M. , ROSSATO M. , VAROTTO A. 
Published: May 2008

SummaryDuring mammalian spermiogenesis, replacement of the somatic histones by basic proteins, the protamines, allows normal sperm nuclear condensation. In this study we have evaluated the degree of chromatin compaction in spermatozoa from 191 infertile subjects, affected by different testicular disorders, compare with that in 50 fertile sperm donors (controls). In infertile men, there was a higher percentage of unstable spermatozoa after incubation with sodium dodecyl sulphate (SDS) and of stained spermatozoa after staining with aniline blue (P <0.001 vs. controls). Furthermore, a positive linear correlation was found between SDS‐unstable spermatozoa and stained spermatozoa (P <0.001), suggesting that sperm instability was related to a defect in histone‐replacement by sperm‐specific nucleoproteins, protamines. When the patients were considered according to pathology, high sperm nuclear instability and a high percentage of stained spermatozoa were detected in groups affected by varicocele, idiopathic infertility and in patients with a history of unilateral cryptorchidism. In the latter group the same alterations were observed even when the cryptorchid testis had been removed during surgery. In the group with a past history of mumps orchitis these parameters did not show any difference when compared with controls.
Semen analysis and fertility prognosis in andrological patients
Authors: HOLLAND‐MORITZ H. , KRAUSE W. 
Published: May 2008

SummarySemen analyses of 529 men who consulted our department due to infertility problems, were related to the time period prior to conception, with factors adversely affecting the fertility of the female partner taken into consideration. The statistical method used was Cox's proportional‐hazard model of regression. Untransformed, logarithmically transformed and dichotomized semen analysis variables were included in the calculations. The relationship between the following parameters and the probability of conception was examined: sperm count, sperm motility, progressive sperm motility, morphology and sperm motility remaining 24 h after ejaculation. All variables co‐varied with the probability of conception; however, the exact type of relationship could not be determined by regression analyses. Cox's model assumes an exponential relationship. Our data suggest that this assumption is not suitable for fertility investigations. Using conventionally defined limiting values for normal and pathological semen quality, statistical analysis yielded significant differences in fertility between both categories for all of the variables considered; in the stepwise regression analysis, however, it could be shown that progressive motility and morphology alone were sufficient to discriminate between normal and pathological semen quality. The results are interpreted as indicating that, as a result of semen analysis, it is possible to predict the individual probability of conception if the exact shape of the relationship can be determined, which, up to now, has not been accomplished.
Residual sperm function in oligozoospermia induced by testosterone enanthate administered as a potential steroid male contraceptive
Authors: WALLACE E. M. , AITKEN R. J. , WU F. C. W. 
Published: May 2008

SummaryTo investigate the fertility of men who remain oligozoospermic despite sex steroid suppression, the in‐vitro fertilizing capacity of residual spermatozoa was assessed in 30 men receiving intramuscular testosterone enanthate (TE). Spermatozoa were prepared by either Percoll or repetitive centrifugation/washing. Although the mean (± SEM) pretreatment zona‐free hamster oocyte penetration (HOP) rates were similar (59.4 ± 10.1 and 63.8 ± 10.8%), following the induction of oligozoospermia the Percoll‐prepared spermatozoa exhibited a penetration rate (26.9 ± 10.2%) which was markedly greater than that obtained for sperm prepared by repetitive washing (0 ± 0%). In addition, the partners of two men exhibiting a HOP test with Percoll‐prepared spermatozoa, conceived despite a sperm concentration of 3 × 106ml‐1 and a negative HOP test with spermatozoa prepared by repetitive washing. These results suggest that Percoll preparation optimizes the assessment of in‐vitro sperm function and that the fertility of men with TE‐induced severe oligozoospermia is suppressed but not abolished.
Infection in the male reproductive tract. Impact, diagnosis and treatment in relation to male infertility
Authors: Purvis K. , Christiansen E. 
Published: May 2008

SummaryThe following are the conclusions that can be derived from a review of the literature regarding the role of infection in the aetiology of male infertility. (i) Temporary inflammatory episodes in the male reproductive tract which are self‐limiting are probably common. (ii) Caution should be exercised in the use of leukospermia or bacteriospermia as parameters for glandular infection. (iii) There is a need for alternative techniques for detecting non‐symptomatic deep pelvic infections in the male; one technique of great promise is rectal ultrasound. (iv) Rectal ultrasound indicates that a large number of men with poor sperm quality have a non‐symptomatic, chronic prostatovesiculitis. (v) Increasing evidence implicates Chlamydia trachomatis as being a major cause of chronic non‐bacterial prostatitis. (vi) An important aspect of chlamydial infections in men may be that the male accessory sex glands may function as reservoirs for the organism, increasing the probability of infection in the female. (vii) Ureaplasma urealyticum may also play an important aetiological role in male infertility but its significance is confounded by its acknowledged function as a commensal in the reproductive tract. (viii) One of the manifestations of male reproductive tract infectiw is the induction of sperm autoantibodies. (ix) There is a need for more systematic controlled studies of the effects of antibiotic treatment on sperm quality with different preparations for extended periods using patient groups in which a glandular infection has been verified, e.g. by rectal ultrasonography.
The time‐response and magnitude of HCG‐induced vascular changes are different in scrotal and abdominal testes
Authors: Hjertkvist M. , Bergh A. 
Published: May 2008

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 rats.
Qualitative assessment of thermal and evaporative adjustments of human scrotal skin in response to heat stress
Authors: CANDAS V. , BECMEUR F. , BOTHOREL B. , HOEFT A. 
Published: May 2008

SummaryTo study scrotal thermoregulation and its efficacy to work against heat accumulation, five subjects were exposed to four experimental conditions under which core and skin temperatures and sweat evaporative responses of various skin surfaces—chest, abdomen and scrotum—were compared. The temperature response of the scrotal area exhibited the largest inertia, and this observation is likely to be the consequence of heat exchange via the vascularization of testes and scrotum which is more efficient than in other parts of the body in limiting local heat storage, thus alleviating heat stress of the testis. The pulsatile nature and the synchronous pattern of the scrotal evaporative heat loss indicate that scrotal sweating takes place, although the gradient response appeared to be less marked than elsewhere in the body. Relatively low and inert scrotal temperature can partly explain this poor local drive for sweating.
Serum levels of testosterone and oestrogens in normal and infertile stallions
Authors: INOUE J. , CERBITO W. A. , OGURI N. , MATSUZAWA T. , SATO K. 
Published: May 2008

SummaryThe serum concentrations of testosterone and oestrogens were determined in stallions classified as geldings, normal (according to age) or infertile (azoospermic). There were significant differences in testosterone and oestrogen levels between the groups. Normal concentrations of testosterone and total oestrogens were attained after 16 months of age. Castrated and immature horses (<15 months of age) had lower levels of testosterone and total oestrogens than did mature and infertile stallions. Azoospermic stallions had lower levels of testosterone and total oestrogens than did normal mature horses except in one case (B4) in which the level of total oestrogens was increased markedly. Critical ellipses for testosterone and total oestrogens were obtained for both groups (6–15‐month‐old colts and stallions aged >4 years). The results suggest that serum levels of testosterone and total oestrogens may provide a sensitive index of the endocrine function of the testis in male horses.