Congenital bilateral absence of the vas deferens (CBAVD) is a frequent cause of obstructive azoospermia, and mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene have also been frequent...Congenital bilateral absence of the vas deferens (CBAVD) is a frequent cause of obstructive azoospermia, and mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene have also been frequently identified in patients with CBAVD. However, the distribution of the CFTR polymorphisms M470V, poly-T, TG-repeats and F508del mutation in the Chinese CBAVD population with presumed low cystic fibrosis (CF) frequency remains to be evaluated. Samples obtained from 109 Chinese infertile males with CBAVD and 104 normal controls were analyzed for the presence of CFTR (TG)m(T)n, M470V and F508del by PCR amplification followed by direct sequencing. Our study showed that the F5OSdel mutation was not found in our patients. The 5T mutation was present with high frequency in Chinese CBAVD patients and IVS8-5T linked to either 12 or 13 TG repeats was highly prevalent among CBAVD patients (97.22% of 72 cases and 96.91% of 97 alleles with IVS8-5T). Moreover, a statistically significant relationship between TG 12-5T-V470 haplotype and CBAVD was detected. This study indicated that the CFTR polymorphisms poly-T, TG-repeats and M470V might affect the process of CBAVD in the Chinese population.展开更多
The vas deferens is a site which can be exploited for male contraception without undue side effects. The only ef-fective technique available for male contraception is vasectomy, being practiced world wide, despite tha...The vas deferens is a site which can be exploited for male contraception without undue side effects. The only ef-fective technique available for male contraception is vasectomy, being practiced world wide, despite that it is a perma-nent surgical procedure and its successful reversal is not assured. Although no-scalpel vasectomy minimizes surgicalprocedures, the fate of its reversal is akin to that of vasectomy. Several occlusive and non-occlusive vasal procedureswhich claim to be reversible without surgical intervention, possess more disadvantages than advantages. Vas occlusionwith plug, ' Shug' or medical grade silicone rubber, although claimed to produce reversible azoospermia without affect-ing spermatogenesis, requires skilled microsurgery for their implantation and later removal. RISUG^R, a non-scleroticpolymer styrene maleic anhydride (SMA), could be more advantageous than vasectomy and other vas occlusive proce-dures in that it could be a totally non-invasive procedure by 'no-scalpel injection' and 'non-invasive reversal'. It isclaimed to offer long-term contraception without adverse side effects and also to be possible as a male spacing methodby repeated vas occlusion and non-invasive reversal. The drug is currently under multicentre Phase Ⅲ clinical trial.展开更多
Congenital bilateral absence of vas deferens (CBAVD) is a manifestation of the mildest form of cystic fibrosis (CF) and is characterized by obstructive azoospermia in otherwise healthy patients. Owing to the avail...Congenital bilateral absence of vas deferens (CBAVD) is a manifestation of the mildest form of cystic fibrosis (CF) and is characterized by obstructive azoospermia in otherwise healthy patients. Owing to the availability of assisted reproductive technology, CBAVD patients can father children. These fathers are at risk of transmitting a mutated allele of the CF transmembrane conductance regulator (CFTR) gene, responsible for CF, to their offspring. The identification of mutations in both CFTR alleles in CBAVD patients is a crucial requirement for calculating the risk of producing a child with full-blown CF if the female partner is a healthy CF carrier. However, in the majority of CBAVD patients, conventional mutation screening is not able to detect mutations in both CFTR alleles, and this difficulty hampers the execution of correct genetic counselling. To obtain information about the most represented CFTR mutations in CBAVD patients, we analysed 23 CBAVD patients, 15 of whom had a single CFTR mutation after screening for 36 mutations and the 5T allele. The search for the second CFTR mutation in these cases was performed by using a triplex approach: (i) first, a reverse dot-blot analysis was performed to detect mutations with regional impact; (ii) next, multiple ligation-dependent probe amplification assays were conducted to search for large rearrangements; and (iii) finally, denaturing high-performance liquid chromatography was used to search for point mutations in the entire coding region. Using these approaches, the second CFTR mutation was detected in six patients, which increased the final detection rate to 60.8%.展开更多
<abstract>Aim: To study the histologic changes of the vas deferens following Nd: YAG laser irradiation. Methods: Intravasal laser irradiation was given to (i) 52 segments of rabbit (laser dosage: 2 seconds at 40...<abstract>Aim: To study the histologic changes of the vas deferens following Nd: YAG laser irradiation. Methods: Intravasal laser irradiation was given to (i) 52 segments of rabbit (laser dosage: 2 seconds at 40 W-50 W) and 16 segments of human (3 seconds at 45 W-55 W) vas deferens in vitro, (ii) 25 rabbit vasa (2 seconds-2.5 seconds at 40 W-45 W) in vivo and (iii) 2 human vasa (3 seconds at 55W) in vivo. Segments of vasa were removed from the in vivo irradiated vasa deferentia 15 days-180 days (rabbit) or 15 days (man) after the exposure. All vas segments were embedded in methacrylate resin. Serial sections (thickness 25μm-30μm) were obtained and observed under a light microscope. Results: (i) Laser-induced damage reached the muscularis layer in 27 % and 94 % of the rabbit and human vas segments in vitro, respectively, (ii) Fourteen of the 25 in vivo rabbit vasa were completely occluded by fibrous tissue and the longer the time interval after treatment, the more likely was the vas occluded. Those unoccluded vasa had either a normal histology or a mucosal damage, (iii) One in vivo human vas was almost completely occluded by the fibrous tissue but the other had a relatively large lumen packed with sperm granulomatous tissue and partial destruction of the smooth muscle layer. Conclusion: Laser irradiation can induce long-term vas occlusion; for rapid occlusion, laser doses just completely destroying the mucosal layer will be advisable.展开更多
Aim: To investigate the morphological changes of spermatozoa in the proximal vas deferens after vasectomy.Methods: Proximal vas deferens fluids were collected from 79 fertile men (group A) and 64 vasectomized men (gro...Aim: To investigate the morphological changes of spermatozoa in the proximal vas deferens after vasectomy.Methods: Proximal vas deferens fluids were collected from 79 fertile men (group A) and 64 vasectomized men (groupB) during the operations of vasectomy or vasovasostomy. Sperm morphology in the proximal vas deferens wasanalyzed after staining with the modified Papanicolaou method. Results: The percentage of spermatozoa with anormal oval head from group B (50.7 % ± 21.7 % ) was significantly lower than that of group A (75.2 % ±11.1%). The data in group A was similar to those of normal semen and therefore represents the physiologicalcondition of the proximal vas deferens sperm of fertile men. There were no significant differences in the percentages ofnormal oval heads in group B with the time since vasectomy. Conclusion: After vasectomy, the spermatozoa in theproximal vas deferens and epididymis were continuously degenerating and being replenished by spermatozoa comingfrom testis. The obvious morphological degeneration occurred in the sperm tail and spermatozoa with a small oval headand amorphous heads were increased.展开更多
We evaluated a biodegradable graft for reconstruction of rat vasa deferentia with long obstructed or missing segments. A total of 47 Sprague-Dawley rats underwent bilateral vasectomy and were divided into groups accor...We evaluated a biodegradable graft for reconstruction of rat vasa deferentia with long obstructed or missing segments. A total of 47 Sprague-Dawley rats underwent bilateral vasectomy and were divided into groups according to length of the vas deferens affected (0.5, 1, 1.5 cm). After 8 weeks, poly-(D,L-lactide) (PDLA) grafts were used to reconnect the vas deferens, Grafts and adjoining vasa deferentia were excised 8 and 12 weeks later and evaluated microscopically. At 8 weeks, microscopic changes included a robust inflammatory response around the grafts. All grafts were still intact but in the early stages of degradation. No microtubules, indicative of vas deferens recanalization, were identified. One specimen showed evidence of healing and neovascularization at the interface zone between the vas deferens and the graft. At 12 weeks, grafts were further degraded but still present. Microscopic evaluation showed decreased inflammation. Seven specimens showed neovascularization at the interface zone; two of these showed distinct epithelialized vas deferens microcanals at the graft edges. One specimen showed a microcanal spanning the entire 0.5-cm graft. A time period of 8 weeks is not ample enough for vas deferens regeneration in the setting of a biodegradable PDLA graft; however, early evidence of re-growth was seen at 12 weeks. A longer healing time should permit further biodegradation of the graft, as well as re-growth and possible eventual reconnection of the vas deferens, allowing passage of sperm. These findings suggest a potential role for biodegradable grafts in the reconstruction ofvas deferens with long obstructed segments.展开更多
文摘Congenital bilateral absence of the vas deferens (CBAVD) is a frequent cause of obstructive azoospermia, and mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene have also been frequently identified in patients with CBAVD. However, the distribution of the CFTR polymorphisms M470V, poly-T, TG-repeats and F508del mutation in the Chinese CBAVD population with presumed low cystic fibrosis (CF) frequency remains to be evaluated. Samples obtained from 109 Chinese infertile males with CBAVD and 104 normal controls were analyzed for the presence of CFTR (TG)m(T)n, M470V and F508del by PCR amplification followed by direct sequencing. Our study showed that the F5OSdel mutation was not found in our patients. The 5T mutation was present with high frequency in Chinese CBAVD patients and IVS8-5T linked to either 12 or 13 TG repeats was highly prevalent among CBAVD patients (97.22% of 72 cases and 96.91% of 97 alleles with IVS8-5T). Moreover, a statistically significant relationship between TG 12-5T-V470 haplotype and CBAVD was detected. This study indicated that the CFTR polymorphisms poly-T, TG-repeats and M470V might affect the process of CBAVD in the Chinese population.
文摘The vas deferens is a site which can be exploited for male contraception without undue side effects. The only ef-fective technique available for male contraception is vasectomy, being practiced world wide, despite that it is a perma-nent surgical procedure and its successful reversal is not assured. Although no-scalpel vasectomy minimizes surgicalprocedures, the fate of its reversal is akin to that of vasectomy. Several occlusive and non-occlusive vasal procedureswhich claim to be reversible without surgical intervention, possess more disadvantages than advantages. Vas occlusionwith plug, ' Shug' or medical grade silicone rubber, although claimed to produce reversible azoospermia without affect-ing spermatogenesis, requires skilled microsurgery for their implantation and later removal. RISUG^R, a non-scleroticpolymer styrene maleic anhydride (SMA), could be more advantageous than vasectomy and other vas occlusive proce-dures in that it could be a totally non-invasive procedure by 'no-scalpel injection' and 'non-invasive reversal'. It isclaimed to offer long-term contraception without adverse side effects and also to be possible as a male spacing methodby repeated vas occlusion and non-invasive reversal. The drug is currently under multicentre Phase Ⅲ clinical trial.
文摘Congenital bilateral absence of vas deferens (CBAVD) is a manifestation of the mildest form of cystic fibrosis (CF) and is characterized by obstructive azoospermia in otherwise healthy patients. Owing to the availability of assisted reproductive technology, CBAVD patients can father children. These fathers are at risk of transmitting a mutated allele of the CF transmembrane conductance regulator (CFTR) gene, responsible for CF, to their offspring. The identification of mutations in both CFTR alleles in CBAVD patients is a crucial requirement for calculating the risk of producing a child with full-blown CF if the female partner is a healthy CF carrier. However, in the majority of CBAVD patients, conventional mutation screening is not able to detect mutations in both CFTR alleles, and this difficulty hampers the execution of correct genetic counselling. To obtain information about the most represented CFTR mutations in CBAVD patients, we analysed 23 CBAVD patients, 15 of whom had a single CFTR mutation after screening for 36 mutations and the 5T allele. The search for the second CFTR mutation in these cases was performed by using a triplex approach: (i) first, a reverse dot-blot analysis was performed to detect mutations with regional impact; (ii) next, multiple ligation-dependent probe amplification assays were conducted to search for large rearrangements; and (iii) finally, denaturing high-performance liquid chromatography was used to search for point mutations in the entire coding region. Using these approaches, the second CFTR mutation was detected in six patients, which increased the final detection rate to 60.8%.
文摘<abstract>Aim: To study the histologic changes of the vas deferens following Nd: YAG laser irradiation. Methods: Intravasal laser irradiation was given to (i) 52 segments of rabbit (laser dosage: 2 seconds at 40 W-50 W) and 16 segments of human (3 seconds at 45 W-55 W) vas deferens in vitro, (ii) 25 rabbit vasa (2 seconds-2.5 seconds at 40 W-45 W) in vivo and (iii) 2 human vasa (3 seconds at 55W) in vivo. Segments of vasa were removed from the in vivo irradiated vasa deferentia 15 days-180 days (rabbit) or 15 days (man) after the exposure. All vas segments were embedded in methacrylate resin. Serial sections (thickness 25μm-30μm) were obtained and observed under a light microscope. Results: (i) Laser-induced damage reached the muscularis layer in 27 % and 94 % of the rabbit and human vas segments in vitro, respectively, (ii) Fourteen of the 25 in vivo rabbit vasa were completely occluded by fibrous tissue and the longer the time interval after treatment, the more likely was the vas occluded. Those unoccluded vasa had either a normal histology or a mucosal damage, (iii) One in vivo human vas was almost completely occluded by the fibrous tissue but the other had a relatively large lumen packed with sperm granulomatous tissue and partial destruction of the smooth muscle layer. Conclusion: Laser irradiation can induce long-term vas occlusion; for rapid occlusion, laser doses just completely destroying the mucosal layer will be advisable.
基金The project was supported by the State Family Planning Committee.
文摘Aim: To investigate the morphological changes of spermatozoa in the proximal vas deferens after vasectomy.Methods: Proximal vas deferens fluids were collected from 79 fertile men (group A) and 64 vasectomized men (groupB) during the operations of vasectomy or vasovasostomy. Sperm morphology in the proximal vas deferens wasanalyzed after staining with the modified Papanicolaou method. Results: The percentage of spermatozoa with anormal oval head from group B (50.7 % ± 21.7 % ) was significantly lower than that of group A (75.2 % ±11.1%). The data in group A was similar to those of normal semen and therefore represents the physiologicalcondition of the proximal vas deferens sperm of fertile men. There were no significant differences in the percentages ofnormal oval heads in group B with the time since vasectomy. Conclusion: After vasectomy, the spermatozoa in theproximal vas deferens and epididymis were continuously degenerating and being replenished by spermatozoa comingfrom testis. The obvious morphological degeneration occurred in the sperm tail and spermatozoa with a small oval headand amorphous heads were increased.
文摘We evaluated a biodegradable graft for reconstruction of rat vasa deferentia with long obstructed or missing segments. A total of 47 Sprague-Dawley rats underwent bilateral vasectomy and were divided into groups according to length of the vas deferens affected (0.5, 1, 1.5 cm). After 8 weeks, poly-(D,L-lactide) (PDLA) grafts were used to reconnect the vas deferens, Grafts and adjoining vasa deferentia were excised 8 and 12 weeks later and evaluated microscopically. At 8 weeks, microscopic changes included a robust inflammatory response around the grafts. All grafts were still intact but in the early stages of degradation. No microtubules, indicative of vas deferens recanalization, were identified. One specimen showed evidence of healing and neovascularization at the interface zone between the vas deferens and the graft. At 12 weeks, grafts were further degraded but still present. Microscopic evaluation showed decreased inflammation. Seven specimens showed neovascularization at the interface zone; two of these showed distinct epithelialized vas deferens microcanals at the graft edges. One specimen showed a microcanal spanning the entire 0.5-cm graft. A time period of 8 weeks is not ample enough for vas deferens regeneration in the setting of a biodegradable PDLA graft; however, early evidence of re-growth was seen at 12 weeks. A longer healing time should permit further biodegradation of the graft, as well as re-growth and possible eventual reconnection of the vas deferens, allowing passage of sperm. These findings suggest a potential role for biodegradable grafts in the reconstruction ofvas deferens with long obstructed segments.