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Derek J. Mclean - One of the best experts on this subject based on the ideXlab platform.
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Analysis of gene expression in bovine Testis tissue prior to Ectopic Testis tissue xenografting and during the grafting period.
Biology of reproduction, 2007Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:The purpose of this study was to identify factors that contribute to bovine Testis development and donor age-dependent differences in the abilities of bovine Ectopic Testis tissue grafts to produce elongated spermatids. We used real-time RT-PCR and microarrays to evaluate and to identify the expression of genes that are involved in Sertoli and germ cell development in bovine Testis tissues. Testis tissues were obtained from 2-, 4-, and 8-wk-old bull calves and were grafted immediately. Grafted bovine Testis tissue was removed from mice, RNA was isolated from the grafts, and real-time RT-PCR was used to evaluate gene expression during the grafting period. In addition, the gene expression in the donor tissue was analyzed using Affymetrix Bovine GeneChips, to identify differentially expressed genes. Examination of the Testis tissue grafts indicated that Sertoli cell-specific gene expression was lower in 8-wk donor tissue grafts compared to the donors of other ages. Furthermore, the expression of KIT, which is a germ cell-specific gene, was low in Testis tissue grafts. Microarray analysis of the donor tissue showed that several genes that are involved in angiogenesis or tissue growth were differentially expressed in 2-, 4-, and 8-wk-old bovine testes. The levels of expression of the genes for angiogenin, transgelin, thrombomodulin, early growth response 1, insulin-like growth factor 2, and insulin-like growth factor-binding protein 3 were lower in Testis tissues from older animals. Using these data, it will be possible in the future to manipulate the Testis xenograft microenvironment so as to improve the efficiency of sperm production within the graft.
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grafting period and donor age affect the potential for spermatogenesis in bovine Ectopic Testis xenografts
Biology of Reproduction, 2006Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:Bovine Testis tissue xenografts contain elongating spermatids 6 mo after grafting. The percentage of seminiferous tubule cross sections with elongating spermatids at the time of graft removal varies depending on donor age and rarely exceeds 10%. These data indicate significant changes are occurring to bovine testicular cells during the first weeks of life. The objective of this research was to xenograft Testis tissue from multiple ages of bull calves for 24 or 36 wk in order to gain a better understanding of early bovine Testis development. Testis tissue from 1-, 2-, 4-, and 8-wk-old calves was grafted onto the backs of castrated immunodeficient mice. Testis tissue from all donor ages grew, differentiated, and produced testosterone and elongating spermatids. Testis tissue grafts from 1- and 8-wk-old calves had elongating spermatids in greater than 5.5% of seminiferous tubule cross sections at the time of graft removal regardless of grafting period. Four-week-old donor tissue never had more than 5.2% of seminiferous tubule cross sections with elongating spermatids. Extending the grafting period from 24 to 36 wk resulted in an increase in the percentage of seminiferous tubule cross sections with elongating spermatids from 2% to 10% in 2-wk donor tissue. These data demonstrate that both donor age and grafting period may be important factors regulating the maturation of bovine Testis xenografts, indicating that intrinsic differences exist within Testis tissue at these donor ages. These data provide the framework for further study of bovine spermatogenesis using Ectopic Testis xenografting.
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Effect of Vascular Endothelial Growth Factor and Testis Tissue Culture on Spermatogenesis in Bovine Ectopic Testis Tissue Xenografts
Biology of reproduction, 2006Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:Bovine Ectopic Testis tissue grafting is a technique that can be used to study bovine spermatogenesis and for the production of germ cells for a variety of applications. Approximately 10% of seminiferous tubule cross sections in Testis grafts contain spermatids, providing a unique tool to investigate what regulates germ cell differentiation. We hypothesized that manipulation of Testis tissue grafts would increase the percentage of seminiferous tubule cross sections undergoing complete germ cell differentiation. To test this hypothesis, bovine Testis tissue was treated with vascular endothelial growth factor (VEGF) at the time of grafting or explant cultured for 1 wk prior to grafting. For the VEGF experiment, 8-wk donor tissue and graft sites were treated with 1 μg of VEGF in order to increase angiogenesis at the graft site. For the Testis tissue culture experiment, 4-wk-old donor Testis was cultured for 1 wk prior to grafting to stimulate spermatogonial stem cell proliferation. Testis tissue grafts were removed from the mice 24 wk after grafting. VEGF treatment increased graft weight and the percentage of seminiferous tubule cross sections with elongating spermatids at the time of graft removal. Cultured Testis tissue grafts were smaller and had fewer seminiferous tubules per graft. However, there was no difference in the percentage of seminiferous tubule cross sections that contained any germ cell type between groups. These data indicate for the first time that bovine Testis tissue can be manipulated to better support germ cell differentiation in grafted tissue.
Jonathan A. Schmidt - One of the best experts on this subject based on the ideXlab platform.
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Analysis of gene expression in bovine Testis tissue prior to Ectopic Testis tissue xenografting and during the grafting period.
Biology of reproduction, 2007Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:The purpose of this study was to identify factors that contribute to bovine Testis development and donor age-dependent differences in the abilities of bovine Ectopic Testis tissue grafts to produce elongated spermatids. We used real-time RT-PCR and microarrays to evaluate and to identify the expression of genes that are involved in Sertoli and germ cell development in bovine Testis tissues. Testis tissues were obtained from 2-, 4-, and 8-wk-old bull calves and were grafted immediately. Grafted bovine Testis tissue was removed from mice, RNA was isolated from the grafts, and real-time RT-PCR was used to evaluate gene expression during the grafting period. In addition, the gene expression in the donor tissue was analyzed using Affymetrix Bovine GeneChips, to identify differentially expressed genes. Examination of the Testis tissue grafts indicated that Sertoli cell-specific gene expression was lower in 8-wk donor tissue grafts compared to the donors of other ages. Furthermore, the expression of KIT, which is a germ cell-specific gene, was low in Testis tissue grafts. Microarray analysis of the donor tissue showed that several genes that are involved in angiogenesis or tissue growth were differentially expressed in 2-, 4-, and 8-wk-old bovine testes. The levels of expression of the genes for angiogenin, transgelin, thrombomodulin, early growth response 1, insulin-like growth factor 2, and insulin-like growth factor-binding protein 3 were lower in Testis tissues from older animals. Using these data, it will be possible in the future to manipulate the Testis xenograft microenvironment so as to improve the efficiency of sperm production within the graft.
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grafting period and donor age affect the potential for spermatogenesis in bovine Ectopic Testis xenografts
Biology of Reproduction, 2006Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:Bovine Testis tissue xenografts contain elongating spermatids 6 mo after grafting. The percentage of seminiferous tubule cross sections with elongating spermatids at the time of graft removal varies depending on donor age and rarely exceeds 10%. These data indicate significant changes are occurring to bovine testicular cells during the first weeks of life. The objective of this research was to xenograft Testis tissue from multiple ages of bull calves for 24 or 36 wk in order to gain a better understanding of early bovine Testis development. Testis tissue from 1-, 2-, 4-, and 8-wk-old calves was grafted onto the backs of castrated immunodeficient mice. Testis tissue from all donor ages grew, differentiated, and produced testosterone and elongating spermatids. Testis tissue grafts from 1- and 8-wk-old calves had elongating spermatids in greater than 5.5% of seminiferous tubule cross sections at the time of graft removal regardless of grafting period. Four-week-old donor tissue never had more than 5.2% of seminiferous tubule cross sections with elongating spermatids. Extending the grafting period from 24 to 36 wk resulted in an increase in the percentage of seminiferous tubule cross sections with elongating spermatids from 2% to 10% in 2-wk donor tissue. These data demonstrate that both donor age and grafting period may be important factors regulating the maturation of bovine Testis xenografts, indicating that intrinsic differences exist within Testis tissue at these donor ages. These data provide the framework for further study of bovine spermatogenesis using Ectopic Testis xenografting.
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Effect of Vascular Endothelial Growth Factor and Testis Tissue Culture on Spermatogenesis in Bovine Ectopic Testis Tissue Xenografts
Biology of reproduction, 2006Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:Bovine Ectopic Testis tissue grafting is a technique that can be used to study bovine spermatogenesis and for the production of germ cells for a variety of applications. Approximately 10% of seminiferous tubule cross sections in Testis grafts contain spermatids, providing a unique tool to investigate what regulates germ cell differentiation. We hypothesized that manipulation of Testis tissue grafts would increase the percentage of seminiferous tubule cross sections undergoing complete germ cell differentiation. To test this hypothesis, bovine Testis tissue was treated with vascular endothelial growth factor (VEGF) at the time of grafting or explant cultured for 1 wk prior to grafting. For the VEGF experiment, 8-wk donor tissue and graft sites were treated with 1 μg of VEGF in order to increase angiogenesis at the graft site. For the Testis tissue culture experiment, 4-wk-old donor Testis was cultured for 1 wk prior to grafting to stimulate spermatogonial stem cell proliferation. Testis tissue grafts were removed from the mice 24 wk after grafting. VEGF treatment increased graft weight and the percentage of seminiferous tubule cross sections with elongating spermatids at the time of graft removal. Cultured Testis tissue grafts were smaller and had fewer seminiferous tubules per graft. However, there was no difference in the percentage of seminiferous tubule cross sections that contained any germ cell type between groups. These data indicate for the first time that bovine Testis tissue can be manipulated to better support germ cell differentiation in grafted tissue.
Jeanene M. De Avila - One of the best experts on this subject based on the ideXlab platform.
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Analysis of gene expression in bovine Testis tissue prior to Ectopic Testis tissue xenografting and during the grafting period.
Biology of reproduction, 2007Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:The purpose of this study was to identify factors that contribute to bovine Testis development and donor age-dependent differences in the abilities of bovine Ectopic Testis tissue grafts to produce elongated spermatids. We used real-time RT-PCR and microarrays to evaluate and to identify the expression of genes that are involved in Sertoli and germ cell development in bovine Testis tissues. Testis tissues were obtained from 2-, 4-, and 8-wk-old bull calves and were grafted immediately. Grafted bovine Testis tissue was removed from mice, RNA was isolated from the grafts, and real-time RT-PCR was used to evaluate gene expression during the grafting period. In addition, the gene expression in the donor tissue was analyzed using Affymetrix Bovine GeneChips, to identify differentially expressed genes. Examination of the Testis tissue grafts indicated that Sertoli cell-specific gene expression was lower in 8-wk donor tissue grafts compared to the donors of other ages. Furthermore, the expression of KIT, which is a germ cell-specific gene, was low in Testis tissue grafts. Microarray analysis of the donor tissue showed that several genes that are involved in angiogenesis or tissue growth were differentially expressed in 2-, 4-, and 8-wk-old bovine testes. The levels of expression of the genes for angiogenin, transgelin, thrombomodulin, early growth response 1, insulin-like growth factor 2, and insulin-like growth factor-binding protein 3 were lower in Testis tissues from older animals. Using these data, it will be possible in the future to manipulate the Testis xenograft microenvironment so as to improve the efficiency of sperm production within the graft.
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grafting period and donor age affect the potential for spermatogenesis in bovine Ectopic Testis xenografts
Biology of Reproduction, 2006Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:Bovine Testis tissue xenografts contain elongating spermatids 6 mo after grafting. The percentage of seminiferous tubule cross sections with elongating spermatids at the time of graft removal varies depending on donor age and rarely exceeds 10%. These data indicate significant changes are occurring to bovine testicular cells during the first weeks of life. The objective of this research was to xenograft Testis tissue from multiple ages of bull calves for 24 or 36 wk in order to gain a better understanding of early bovine Testis development. Testis tissue from 1-, 2-, 4-, and 8-wk-old calves was grafted onto the backs of castrated immunodeficient mice. Testis tissue from all donor ages grew, differentiated, and produced testosterone and elongating spermatids. Testis tissue grafts from 1- and 8-wk-old calves had elongating spermatids in greater than 5.5% of seminiferous tubule cross sections at the time of graft removal regardless of grafting period. Four-week-old donor tissue never had more than 5.2% of seminiferous tubule cross sections with elongating spermatids. Extending the grafting period from 24 to 36 wk resulted in an increase in the percentage of seminiferous tubule cross sections with elongating spermatids from 2% to 10% in 2-wk donor tissue. These data demonstrate that both donor age and grafting period may be important factors regulating the maturation of bovine Testis xenografts, indicating that intrinsic differences exist within Testis tissue at these donor ages. These data provide the framework for further study of bovine spermatogenesis using Ectopic Testis xenografting.
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Effect of Vascular Endothelial Growth Factor and Testis Tissue Culture on Spermatogenesis in Bovine Ectopic Testis Tissue Xenografts
Biology of reproduction, 2006Co-Authors: Jonathan A. Schmidt, Jeanene M. De Avila, Derek J. McleanAbstract:Bovine Ectopic Testis tissue grafting is a technique that can be used to study bovine spermatogenesis and for the production of germ cells for a variety of applications. Approximately 10% of seminiferous tubule cross sections in Testis grafts contain spermatids, providing a unique tool to investigate what regulates germ cell differentiation. We hypothesized that manipulation of Testis tissue grafts would increase the percentage of seminiferous tubule cross sections undergoing complete germ cell differentiation. To test this hypothesis, bovine Testis tissue was treated with vascular endothelial growth factor (VEGF) at the time of grafting or explant cultured for 1 wk prior to grafting. For the VEGF experiment, 8-wk donor tissue and graft sites were treated with 1 μg of VEGF in order to increase angiogenesis at the graft site. For the Testis tissue culture experiment, 4-wk-old donor Testis was cultured for 1 wk prior to grafting to stimulate spermatogonial stem cell proliferation. Testis tissue grafts were removed from the mice 24 wk after grafting. VEGF treatment increased graft weight and the percentage of seminiferous tubule cross sections with elongating spermatids at the time of graft removal. Cultured Testis tissue grafts were smaller and had fewer seminiferous tubules per graft. However, there was no difference in the percentage of seminiferous tubule cross sections that contained any germ cell type between groups. These data indicate for the first time that bovine Testis tissue can be manipulated to better support germ cell differentiation in grafted tissue.
T Patankar - One of the best experts on this subject based on the ideXlab platform.
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persistent mullerian duct syndrome with teratoma in an Ectopic Testis imaging features
European Radiology, 2001Co-Authors: Ranjeet S Narlawar, J Shah, Vipul Parikh, T PatankarAbstract:The persistent mullerian duct syndrome represents a rare form of male pseudohermaphroditism, secondary to mullerian inhibiting factor (MIF) deficiency. We describe imaging findings in a 30-year-old male (46 XY karyotype) with bilateral cryptorchidism and mullerian duct anomalies (presence of uterus and fallopian tubes). Grade-III teratoma with yolk sac tumour was detected in one of the undescended Testis, lying in the pelvic cavity. The other Testis was in the inguinal canal. The rest of the wolffian duct structures (e. g. prostate, seminal vesicles) were nearly normal. Very few reports of imaging findings of this entity have been published thus far, probably because of the rarity of entity, incidental detection of most of the cases at surgery and relatively asymptomatic clinical presentation.
Kenji Shimada - One of the best experts on this subject based on the ideXlab platform.
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A Case of Chromosomal Disorders of Sex Development with Transverse Testicular Ectopia Mimicking Mixed Gonadal Dysgenesis
Urology, 2016Co-Authors: Fumi Matsumoto, Futoshi Matsui, Koji Yazawa, Kenji ShimadaAbstract:Transverse testicular ectopia (TTE) is a rare form of Ectopic Testis observed in boys with a normal 46, XY karyotype. TTE can be associated with persistent Mullerian duct syndrome or other genital anomalies such as hypospadias. However, TTE concomitant with both persistent Mullerian duct remnants and hypospadias has never been reported in the literature. A case of chromosomal disorders of sex development with TTE and persistent Mullerian duct remnants, which was initially presumed to represent mixed gonadal dysgenesis, is presented.
