CONCLUSÕES REFERÊNCIAS 1Estudante de Ciências Biológicas do UniCEUB e Bolsista da Embrapa Cerrado... more CONCLUSÕES REFERÊNCIAS 1Estudante de Ciências Biológicas do UniCEUB e Bolsista da Embrapa Cerrados, BR 020 km 18, Planaltina, DF, CEP 73301-970 [email protected], 2 3 Estudante de Agronomia da UPIS e Bolsista da Embrapa Cerrados, Pesquisadores da Embrapa Cerrados, 4 5 Pesquisador da Embrapa Recursos Genéticos e Biotecnologia e Pesquisadora da Embrapa Mandioca e Fruticultura. i i i l i i l i l l i ll i l i i i i i l i i i i l COMPARAÇÃO DE MÉTODOS DE PRODUÇÃO DE ESPOROS DE Beauveria bassiana, Metarhizium anisopliae E Sporothrix insectorum i i i i i li i i
Introducao: O melanoforoma e uma neoplasia neuroectodermica rara originada de celulas pigmentares... more Introducao: O melanoforoma e uma neoplasia neuroectodermica rara originada de celulas pigmentares da epiderme (melanoforos). Ha poucos casos descritos em todo o mundo e a sua maioria acometendo serpentes. No Brasil ate o momento, essa enfermidade nao foi descrita em repteis. Alguns casos de melanoforomas foram observados em lagartos (Garner et al. 2004, Irizarry-Rovira et al. 2006, Simpson 2008) e na carapaca de tartarugas (Hermann et al.2011). O diagnostico das neoplasias de celulas pigmentares e realizado atraves do exame anatomopatologico, pela imuno-histoquimica para detectar os antigenos celulares Melan A e S 100, e ainda pela caracterizacao ultra estrutural para a diferenciacao entre os melanoforos, que produzem ativamente a melanina e as celulas epiteliais que armazenam esse pigmento (Ramos-Vara et al. 2000). Nos ultimos anos, o interesse por serpentes como animais pet, assim como a melhoria dos cuidados com esses repteis mantidos em cativeiro e zoologicos, aumentaram o inter...
The intra-puparial development of the blowflies Cochliomyia macellaria (n = 310) and Lucilia cupr... more The intra-puparial development of the blowflies Cochliomyia macellaria (n = 310) and Lucilia cuprina (n = 470), was studied under controlled conditions in laboratory. The 3rd instar larvae were reared until they stopped feeding, and the pre-pupae were separated according to the size in larval length and degree of pigmentation and of the cuticle. We observe a set of five continuous events or phases: (1) pupariation, (2) larva-pupa apolysis, (3) cryptocephalic pupa, (4) phanerocephalic pupa and (5) pharate adult. The total time of the intra-puparial development, larva-pupa apolysis to pharate adult, lasted for 120 h (5 days) to C. macellaria and 210 h (8.75 days) to L. cuprina.
We investigated the effects of progesterone and follicle stimulating hormone (FSH) on survival an... more We investigated the effects of progesterone and follicle stimulating hormone (FSH) on survival and growth of caprine preantral follicles. Pieces of ovarian tissue were cultured for 1 or 7 days in minimum essential medium (MEM) alone or containing progesterone (1, 2.5, 5, 10 or 20ng/mL), FSH (50ng/mL) or the interaction between progesterone and FSH. Fresh (non-cultured control) and cultured ovarian tissues were processed for histological and ultrastructural studies. After 7 days the addition of FSH to all progesterone concentrations maintained the percentage of normal follicles similar to fresh control. At day 7 of culture, a higher percentage of developing follicles was observed only in 2.5ng/ml of progesterone associated with FSH or 10ng/ml of progesterone alone when compared with control. From day 1 to day 7 of culture, a significant increase in the percentage of developing follicles was observed in MEM and 2.5ng/ml of progesterone + FSH. In addition, after 7 days, in all treatmen...
The objective of this study was to characterize, structurally and ultrastructurally, the spermato... more The objective of this study was to characterize, structurally and ultrastructurally, the spermatozoa of the screwworm flies Cochliomyia hominivorax and Cochliomyia macellaria. To visualize the ultrastructure of microtubules and identify basic proteins, techniques such as the tannic acid fixation and the cytochemical method of ethanolic phosphotungstic acid (EPTA) were used. These methods of fixation are important because they reinforce the evidence of the protofilaments present in the microtubular wall and identify basic proteins, respectively. With the tannic acid fixative it was possible to observe a significant number of microtubules in the cell cytoplasm during spermiogenesis. Microtubules were observed in all regions of spermatids (head, 'overlap' zone and tail). The EPTA technique highlighted the presence of basic proteins on the border of the nucleus and nuclear envelope in the two species analyzed, and in the centriolar adjunct and on the border of mitochondrial derivatives in C. macellaria. The axoneme is of a conventional insect type with a 9 + 9 + 2 microtubular arrangement and the spermatozoa of C. hominivorax and C. macellaria are similar to those described for other Brachycera. The spermatozoa are long and thin in these two species, ∼190 µm in length, of which the head region measures ∼26 µm in C. hominivorax and 29 µm in C. macellaria. A polymorphism was observed in C. hominivorax and C. macellaria. These features are consistent with the structural diversity of the dipteran spermatozoa, constituting an essential tool for understanding the complex variations found in the Diptera order.
The objective of the present study was to describe ultrastructural changes in the nucleus and cyt... more The objective of the present study was to describe ultrastructural changes in the nucleus and cytoplasmic organelles during in vitro maturation (IVM) of buffalo cumulus-oocyte complexes (COCs). The structures were collected by ovum pick-up (OPU). Some COCs, removed from maturation medium at 0, 6, 12, 18 and 24 h, were processed for transmission electron microscopy. The average number of COCs collected by OPU/animal/session was 6.4, and 44% of them were viable. Immature oocytes had a peripherally located nucleus, Golgi complex and mitochondrial clusters, as well as a large number of coalescent lipid vacuoles. After 6 h of IVM, the oocyte nucleus morphology changed from round to a flatter shape, and the granulosa cells (GC) lost most of their contact with zona pellucida (ZP). At 12 h the first polar body was extruded and the aspect of lipid droplet changed to dark, probably denoting lipid oxidation. Cortical granules were clearly visible at 18 h of maturation, always located along the oocyte periphery. At 24 h of IVM the number of cortical granules increased. Ultrastructure studies revealed that: (1) immature oocytes have a high lipid content; (2) the perivitelline space (PS) increases during IVM; (3) Golgi complexes and mitochondrial clusters migrate to oocyte periphery during IVM; (4) 6 h of IVM are enough to lose contact between GC and ZP; (5) the oocyte lipid droplets' appearance changes between 6 and 12 h of IVM.
The aim of the present study was to investigate the effects of fibroblast growth factor-10 (FGF-1... more The aim of the present study was to investigate the effects of fibroblast growth factor-10 (FGF-10) on the survival, activation (transition from primordial to primary follicles), and growth of goat preantral follicles cultured in vitro. Pieces of ovarian cortex were cultured for 1 and 7 d in the absence or presence of FGF-10 (0, 1, 10, 50, 100, and 200 ng/mL). Noncultured and cultured tissues were processed and analyzed by histology, transmission electron microscopy, and viability testing. Results showed that after 7 d, a greater percentage (79.9%) of morphologically normal follicles (containing an oocyte with regular shape and uniform cytoplasm, and organized layers of granulosa cells without a pyknotic nucleus) was observed when cultured with 50 ng/mL of FGF-10 when compared with other concentrations of FGF-10 (0 ng/mL, 67.3%; 1 ng/mL, 68.2%; 10 ng/mL, 63.3%; 100 ng/mL, 64.4%; 200 ng/mL, 52.7%). Ultrastructural analyses and viability testing using fluorescent markers confirmed the follicular integrity of FGF-10 (50 ng/mL)-treated fragments after 7 d of culture. After 7 d, all FGF-10 concentrations reduced the percentage of primordial follicles and increased the percentage of developing follicles. In the presence of 50 ng/mL of FGF-10, follicles increased in diameter after 7 d of culture when compared with other concentrations tested. In conclusion, this study demonstrates that FGF-10 maintains the morphological integrity of goat preantral follicles and stimulates the growth of activated follicles in culture. The culture conditions identified here contribute to the understanding of the factors involved in goat early follicular development.
The aim of this study was to investigate the effects of nerve growth factor (NGF) on the in vitro... more The aim of this study was to investigate the effects of nerve growth factor (NGF) on the in vitro culture of goat preantral follicles. Ovarian cortex fragments were cultured in α-MEM+ supplemented with 0, 1, 10, 50, 100 or 200 ng/ml NGF for 1 or 7 days. Small fragments of noncultured ovarian tissue as well as those cultured for 1 or 7 days were processed for histology and transmission electron microscopy. The results showed that after 1 or 7 days of culture at all concentrations of NGF, except at 1 ng/ml after 1 day of culture, there was a significant reduction in the percentage of normal follicles compared to noncultured tissues. At higher NGF concentrations (100 and 200 ng/ml) after 7 days of culture, there was a significant reduction in the percentage of normal follicles compared to tissues cultured in α-MEM+ alone or at the other concentrations of NGF. It is important to note that ultrastructural and fluorescent analyses confirmed only the integrity of follicles cultured with 1 ng/ml of NGF after 7 days. In contrast to noncultured control tissues, the percentage of developing follicles was significantly increased at all concentrations of NGF after 1 or 7 days of culture. We observed that follicular diameter was greater at 1 and 10 ng/ml NGF after culture for 7 days than at the other concentrations but was similar to follicles cultured in α-MEM+ alone. In conclusion, NGF improved the survival of goat preantral follicles cultured in vitro in a dose-dependent manner.
This study evaluates the effects of ascorbic acid and its interaction with follicle-stimulating h... more This study evaluates the effects of ascorbic acid and its interaction with follicle-stimulating hormone (FSH) on the morphology, activation, and in vitro growth of caprine preantral follicles. Ovarian fragments were cultured for 1, 7, or 14 d in minimum essential medium (MEM) containing ascorbic acid (50 or 100microg/mL), FSH (50ng/mL), or both of these substances. Ovarian tissue that was either fresh (control) or cultured for 1, 7, or 14 d was processed for histological and ultrastructural evaluation. The results showed that after 14 d of culture, medium supplemented with 50microg/mL of ascorbic acid alone or combined with FSH showed higher rates of follicular survival compared with MEM. After 7 d of culture, FSH, ascorbic acid at 50microg/mL with or without FSH, and ascorbic acid at 100microg/mL increased the percentage of follicular activation compared to fresh control. In addition, FSH alone significantly increased the percentage of growing follicles after 14 d. The combination ...
The aim of this study was to investigate the effects of estradiol and follicle-stimulating hormon... more The aim of this study was to investigate the effects of estradiol and follicle-stimulating hormone (FSH) on survival and growth of caprine preantral follicles. Pieces of ovarian tissue were cultured for 1 or 7 days in minimum essential medium (MEM) containing estradiol (1, 5, 10, 20 or 40 pg/ml), FSH (50 ng/ml), or a combination of the two hormones. Cultured and noncultured control ovarian tissues were processed for histological and ultrastructural studies. The results showed that after 7 days of culture, the treatments that yielded the highest percentage of normal follicles relative to MEM alone were those that combined FSH with estradiol at 1, 5 or 20 pg/ml. The addition of FSH to 1-day cultures containing 1 pg/ml estradiol or to 7-day cultures with 1 or 5 pg/ml estradiol increased the percentage of normal follicles compared to estradiol alone at the same concentrations. After 7 days of culture, all treatments generated higher percentages of developing follicles as compared to control and MEM alone. The addition of either FSH or 10 pg/ml of estradiol to the culture media or estradiol (1, 5, 10 or 20 pg/ml) and FSH in combination significantly increased follicular diameter as compared with MEM alone following 7 days of culture. Ultrastructural studies confirmed follicular integrity after 7 days of culture in the presence of 1 pg/ml estradiol plus FSH. In conclusion, this study demonstrated that the interaction between estradiol and FSH maintains ultrastructural integrity and stimulates activation and further growth of cultured caprine preantral follicles.
The aim of the present study was to evaluate the effects of storage of goat ovarian fragments at ... more The aim of the present study was to evaluate the effects of storage of goat ovarian fragments at different temperatures and for different incubation times on the viability and growth of cultured preantral follicles in vitro. Caprine ovaries were collected and divided into 19 fragments, with one fragment being fixed immediately (fresh control). The remaining fragments were placed in minimal essential medium (MEM) and maintained at 4, 20 or 35 • C for 2 or 4 h. After each incubation period, some of the fragments were fixed (non-cultured), whereas others were cultured in vitro for 1 or 7 days. Fragments were processed to enable routine histological and transmission electron microscopic examination. After 7 days of culture, only ovarian fragments stored at 4 • C for 4 h maintained a percentage of morphologically normal follicles similar to that in the fresh control. For all other treatments groups, there was a significant increase in follicular activation observed. In addition, there was an increase in oocyte and follicular diameter after culture of ovarian cortex that had been chilled previously at 4 • C for 2 or 4 h. In conclusion, the present study demonstrated that chilling ovarian fragments at 4 • C during transportation is best for maintaining follicle viability and to increase follicular growth during in vitro culture.
The aim of this study was to evaluate the effect of vasoactive intestinal peptide (VIP)on the sur... more The aim of this study was to evaluate the effect of vasoactive intestinal peptide (VIP)on the survival, activation and growth of goat preantral follicles after in vitro culture. The ovarian cortex was divided into small pieces and one fragment was immediately fixed (control). The remaining fragments were cultured in vitro for 1 or 7 days at 39 degrees C and 5% CO(2), in supplemented minimum essential medium (MEM(+)) with or without different concentrations of VIP (1, 10, 50, 100 or 200 ng/ml). Noncultured (fresh control) and cultured ovarian fragments were processed for histological analysis and transmission electron microscopy. Follicles were classified as primordial or developing, and as normal or degenerated. Our findings indicate that when compared with control, addition of all concentrations of VIP except 200 ng/ml resulted in similar percentages of normal preantral follicles after 1 and 7 days of culture. Culture of ovarian cortex tissue for 1 and 7 days increased the percentage of follicular activation in all treatments when compared with control, except with 1 ng/ml of VIP after 1 day. However, no difference was observed between VIP-treated and MEM(+)-treated follicles. In addition, after 7 days of culture, the highest follicular and oocyte diameters were observed in follicles cultured with 10 ng/ml VIP relative to MEM(+) alone. Transmission electron microscopy showed ultrastructural integrity of follicles after 7 days of culture in 10 ng/ml VIP. In conclusion, this study demonstrates that VIP maintains follicular integrity and stimulates caprine preantral follicle growth.
Please cite this article in press as: Name, K.P.O., et al., Structure and ultrastructure of sperm... more Please cite this article in press as: Name, K.P.O., et al., Structure and ultrastructure of spermatozoa of Chrysomya megacephala (Diptera: Calliphoridae). Micron (2010), a b s t r a c t
CONCLUSÕES REFERÊNCIAS 1Estudante de Ciências Biológicas do UniCEUB e Bolsista da Embrapa Cerrado... more CONCLUSÕES REFERÊNCIAS 1Estudante de Ciências Biológicas do UniCEUB e Bolsista da Embrapa Cerrados, BR 020 km 18, Planaltina, DF, CEP 73301-970 [email protected], 2 3 Estudante de Agronomia da UPIS e Bolsista da Embrapa Cerrados, Pesquisadores da Embrapa Cerrados, 4 5 Pesquisador da Embrapa Recursos Genéticos e Biotecnologia e Pesquisadora da Embrapa Mandioca e Fruticultura. i i i l i i l i l l i ll i l i i i i i l i i i i l COMPARAÇÃO DE MÉTODOS DE PRODUÇÃO DE ESPOROS DE Beauveria bassiana, Metarhizium anisopliae E Sporothrix insectorum i i i i i li i i
Introducao: O melanoforoma e uma neoplasia neuroectodermica rara originada de celulas pigmentares... more Introducao: O melanoforoma e uma neoplasia neuroectodermica rara originada de celulas pigmentares da epiderme (melanoforos). Ha poucos casos descritos em todo o mundo e a sua maioria acometendo serpentes. No Brasil ate o momento, essa enfermidade nao foi descrita em repteis. Alguns casos de melanoforomas foram observados em lagartos (Garner et al. 2004, Irizarry-Rovira et al. 2006, Simpson 2008) e na carapaca de tartarugas (Hermann et al.2011). O diagnostico das neoplasias de celulas pigmentares e realizado atraves do exame anatomopatologico, pela imuno-histoquimica para detectar os antigenos celulares Melan A e S 100, e ainda pela caracterizacao ultra estrutural para a diferenciacao entre os melanoforos, que produzem ativamente a melanina e as celulas epiteliais que armazenam esse pigmento (Ramos-Vara et al. 2000). Nos ultimos anos, o interesse por serpentes como animais pet, assim como a melhoria dos cuidados com esses repteis mantidos em cativeiro e zoologicos, aumentaram o inter...
The intra-puparial development of the blowflies Cochliomyia macellaria (n = 310) and Lucilia cupr... more The intra-puparial development of the blowflies Cochliomyia macellaria (n = 310) and Lucilia cuprina (n = 470), was studied under controlled conditions in laboratory. The 3rd instar larvae were reared until they stopped feeding, and the pre-pupae were separated according to the size in larval length and degree of pigmentation and of the cuticle. We observe a set of five continuous events or phases: (1) pupariation, (2) larva-pupa apolysis, (3) cryptocephalic pupa, (4) phanerocephalic pupa and (5) pharate adult. The total time of the intra-puparial development, larva-pupa apolysis to pharate adult, lasted for 120 h (5 days) to C. macellaria and 210 h (8.75 days) to L. cuprina.
We investigated the effects of progesterone and follicle stimulating hormone (FSH) on survival an... more We investigated the effects of progesterone and follicle stimulating hormone (FSH) on survival and growth of caprine preantral follicles. Pieces of ovarian tissue were cultured for 1 or 7 days in minimum essential medium (MEM) alone or containing progesterone (1, 2.5, 5, 10 or 20ng/mL), FSH (50ng/mL) or the interaction between progesterone and FSH. Fresh (non-cultured control) and cultured ovarian tissues were processed for histological and ultrastructural studies. After 7 days the addition of FSH to all progesterone concentrations maintained the percentage of normal follicles similar to fresh control. At day 7 of culture, a higher percentage of developing follicles was observed only in 2.5ng/ml of progesterone associated with FSH or 10ng/ml of progesterone alone when compared with control. From day 1 to day 7 of culture, a significant increase in the percentage of developing follicles was observed in MEM and 2.5ng/ml of progesterone + FSH. In addition, after 7 days, in all treatmen...
The objective of this study was to characterize, structurally and ultrastructurally, the spermato... more The objective of this study was to characterize, structurally and ultrastructurally, the spermatozoa of the screwworm flies Cochliomyia hominivorax and Cochliomyia macellaria. To visualize the ultrastructure of microtubules and identify basic proteins, techniques such as the tannic acid fixation and the cytochemical method of ethanolic phosphotungstic acid (EPTA) were used. These methods of fixation are important because they reinforce the evidence of the protofilaments present in the microtubular wall and identify basic proteins, respectively. With the tannic acid fixative it was possible to observe a significant number of microtubules in the cell cytoplasm during spermiogenesis. Microtubules were observed in all regions of spermatids (head, 'overlap' zone and tail). The EPTA technique highlighted the presence of basic proteins on the border of the nucleus and nuclear envelope in the two species analyzed, and in the centriolar adjunct and on the border of mitochondrial derivatives in C. macellaria. The axoneme is of a conventional insect type with a 9 + 9 + 2 microtubular arrangement and the spermatozoa of C. hominivorax and C. macellaria are similar to those described for other Brachycera. The spermatozoa are long and thin in these two species, ∼190 µm in length, of which the head region measures ∼26 µm in C. hominivorax and 29 µm in C. macellaria. A polymorphism was observed in C. hominivorax and C. macellaria. These features are consistent with the structural diversity of the dipteran spermatozoa, constituting an essential tool for understanding the complex variations found in the Diptera order.
The objective of the present study was to describe ultrastructural changes in the nucleus and cyt... more The objective of the present study was to describe ultrastructural changes in the nucleus and cytoplasmic organelles during in vitro maturation (IVM) of buffalo cumulus-oocyte complexes (COCs). The structures were collected by ovum pick-up (OPU). Some COCs, removed from maturation medium at 0, 6, 12, 18 and 24 h, were processed for transmission electron microscopy. The average number of COCs collected by OPU/animal/session was 6.4, and 44% of them were viable. Immature oocytes had a peripherally located nucleus, Golgi complex and mitochondrial clusters, as well as a large number of coalescent lipid vacuoles. After 6 h of IVM, the oocyte nucleus morphology changed from round to a flatter shape, and the granulosa cells (GC) lost most of their contact with zona pellucida (ZP). At 12 h the first polar body was extruded and the aspect of lipid droplet changed to dark, probably denoting lipid oxidation. Cortical granules were clearly visible at 18 h of maturation, always located along the oocyte periphery. At 24 h of IVM the number of cortical granules increased. Ultrastructure studies revealed that: (1) immature oocytes have a high lipid content; (2) the perivitelline space (PS) increases during IVM; (3) Golgi complexes and mitochondrial clusters migrate to oocyte periphery during IVM; (4) 6 h of IVM are enough to lose contact between GC and ZP; (5) the oocyte lipid droplets' appearance changes between 6 and 12 h of IVM.
The aim of the present study was to investigate the effects of fibroblast growth factor-10 (FGF-1... more The aim of the present study was to investigate the effects of fibroblast growth factor-10 (FGF-10) on the survival, activation (transition from primordial to primary follicles), and growth of goat preantral follicles cultured in vitro. Pieces of ovarian cortex were cultured for 1 and 7 d in the absence or presence of FGF-10 (0, 1, 10, 50, 100, and 200 ng/mL). Noncultured and cultured tissues were processed and analyzed by histology, transmission electron microscopy, and viability testing. Results showed that after 7 d, a greater percentage (79.9%) of morphologically normal follicles (containing an oocyte with regular shape and uniform cytoplasm, and organized layers of granulosa cells without a pyknotic nucleus) was observed when cultured with 50 ng/mL of FGF-10 when compared with other concentrations of FGF-10 (0 ng/mL, 67.3%; 1 ng/mL, 68.2%; 10 ng/mL, 63.3%; 100 ng/mL, 64.4%; 200 ng/mL, 52.7%). Ultrastructural analyses and viability testing using fluorescent markers confirmed the follicular integrity of FGF-10 (50 ng/mL)-treated fragments after 7 d of culture. After 7 d, all FGF-10 concentrations reduced the percentage of primordial follicles and increased the percentage of developing follicles. In the presence of 50 ng/mL of FGF-10, follicles increased in diameter after 7 d of culture when compared with other concentrations tested. In conclusion, this study demonstrates that FGF-10 maintains the morphological integrity of goat preantral follicles and stimulates the growth of activated follicles in culture. The culture conditions identified here contribute to the understanding of the factors involved in goat early follicular development.
The aim of this study was to investigate the effects of nerve growth factor (NGF) on the in vitro... more The aim of this study was to investigate the effects of nerve growth factor (NGF) on the in vitro culture of goat preantral follicles. Ovarian cortex fragments were cultured in α-MEM+ supplemented with 0, 1, 10, 50, 100 or 200 ng/ml NGF for 1 or 7 days. Small fragments of noncultured ovarian tissue as well as those cultured for 1 or 7 days were processed for histology and transmission electron microscopy. The results showed that after 1 or 7 days of culture at all concentrations of NGF, except at 1 ng/ml after 1 day of culture, there was a significant reduction in the percentage of normal follicles compared to noncultured tissues. At higher NGF concentrations (100 and 200 ng/ml) after 7 days of culture, there was a significant reduction in the percentage of normal follicles compared to tissues cultured in α-MEM+ alone or at the other concentrations of NGF. It is important to note that ultrastructural and fluorescent analyses confirmed only the integrity of follicles cultured with 1 ng/ml of NGF after 7 days. In contrast to noncultured control tissues, the percentage of developing follicles was significantly increased at all concentrations of NGF after 1 or 7 days of culture. We observed that follicular diameter was greater at 1 and 10 ng/ml NGF after culture for 7 days than at the other concentrations but was similar to follicles cultured in α-MEM+ alone. In conclusion, NGF improved the survival of goat preantral follicles cultured in vitro in a dose-dependent manner.
This study evaluates the effects of ascorbic acid and its interaction with follicle-stimulating h... more This study evaluates the effects of ascorbic acid and its interaction with follicle-stimulating hormone (FSH) on the morphology, activation, and in vitro growth of caprine preantral follicles. Ovarian fragments were cultured for 1, 7, or 14 d in minimum essential medium (MEM) containing ascorbic acid (50 or 100microg/mL), FSH (50ng/mL), or both of these substances. Ovarian tissue that was either fresh (control) or cultured for 1, 7, or 14 d was processed for histological and ultrastructural evaluation. The results showed that after 14 d of culture, medium supplemented with 50microg/mL of ascorbic acid alone or combined with FSH showed higher rates of follicular survival compared with MEM. After 7 d of culture, FSH, ascorbic acid at 50microg/mL with or without FSH, and ascorbic acid at 100microg/mL increased the percentage of follicular activation compared to fresh control. In addition, FSH alone significantly increased the percentage of growing follicles after 14 d. The combination ...
The aim of this study was to investigate the effects of estradiol and follicle-stimulating hormon... more The aim of this study was to investigate the effects of estradiol and follicle-stimulating hormone (FSH) on survival and growth of caprine preantral follicles. Pieces of ovarian tissue were cultured for 1 or 7 days in minimum essential medium (MEM) containing estradiol (1, 5, 10, 20 or 40 pg/ml), FSH (50 ng/ml), or a combination of the two hormones. Cultured and noncultured control ovarian tissues were processed for histological and ultrastructural studies. The results showed that after 7 days of culture, the treatments that yielded the highest percentage of normal follicles relative to MEM alone were those that combined FSH with estradiol at 1, 5 or 20 pg/ml. The addition of FSH to 1-day cultures containing 1 pg/ml estradiol or to 7-day cultures with 1 or 5 pg/ml estradiol increased the percentage of normal follicles compared to estradiol alone at the same concentrations. After 7 days of culture, all treatments generated higher percentages of developing follicles as compared to control and MEM alone. The addition of either FSH or 10 pg/ml of estradiol to the culture media or estradiol (1, 5, 10 or 20 pg/ml) and FSH in combination significantly increased follicular diameter as compared with MEM alone following 7 days of culture. Ultrastructural studies confirmed follicular integrity after 7 days of culture in the presence of 1 pg/ml estradiol plus FSH. In conclusion, this study demonstrated that the interaction between estradiol and FSH maintains ultrastructural integrity and stimulates activation and further growth of cultured caprine preantral follicles.
The aim of the present study was to evaluate the effects of storage of goat ovarian fragments at ... more The aim of the present study was to evaluate the effects of storage of goat ovarian fragments at different temperatures and for different incubation times on the viability and growth of cultured preantral follicles in vitro. Caprine ovaries were collected and divided into 19 fragments, with one fragment being fixed immediately (fresh control). The remaining fragments were placed in minimal essential medium (MEM) and maintained at 4, 20 or 35 • C for 2 or 4 h. After each incubation period, some of the fragments were fixed (non-cultured), whereas others were cultured in vitro for 1 or 7 days. Fragments were processed to enable routine histological and transmission electron microscopic examination. After 7 days of culture, only ovarian fragments stored at 4 • C for 4 h maintained a percentage of morphologically normal follicles similar to that in the fresh control. For all other treatments groups, there was a significant increase in follicular activation observed. In addition, there was an increase in oocyte and follicular diameter after culture of ovarian cortex that had been chilled previously at 4 • C for 2 or 4 h. In conclusion, the present study demonstrated that chilling ovarian fragments at 4 • C during transportation is best for maintaining follicle viability and to increase follicular growth during in vitro culture.
The aim of this study was to evaluate the effect of vasoactive intestinal peptide (VIP)on the sur... more The aim of this study was to evaluate the effect of vasoactive intestinal peptide (VIP)on the survival, activation and growth of goat preantral follicles after in vitro culture. The ovarian cortex was divided into small pieces and one fragment was immediately fixed (control). The remaining fragments were cultured in vitro for 1 or 7 days at 39 degrees C and 5% CO(2), in supplemented minimum essential medium (MEM(+)) with or without different concentrations of VIP (1, 10, 50, 100 or 200 ng/ml). Noncultured (fresh control) and cultured ovarian fragments were processed for histological analysis and transmission electron microscopy. Follicles were classified as primordial or developing, and as normal or degenerated. Our findings indicate that when compared with control, addition of all concentrations of VIP except 200 ng/ml resulted in similar percentages of normal preantral follicles after 1 and 7 days of culture. Culture of ovarian cortex tissue for 1 and 7 days increased the percentage of follicular activation in all treatments when compared with control, except with 1 ng/ml of VIP after 1 day. However, no difference was observed between VIP-treated and MEM(+)-treated follicles. In addition, after 7 days of culture, the highest follicular and oocyte diameters were observed in follicles cultured with 10 ng/ml VIP relative to MEM(+) alone. Transmission electron microscopy showed ultrastructural integrity of follicles after 7 days of culture in 10 ng/ml VIP. In conclusion, this study demonstrates that VIP maintains follicular integrity and stimulates caprine preantral follicle growth.
Please cite this article in press as: Name, K.P.O., et al., Structure and ultrastructure of sperm... more Please cite this article in press as: Name, K.P.O., et al., Structure and ultrastructure of spermatozoa of Chrysomya megacephala (Diptera: Calliphoridae). Micron (2010), a b s t r a c t
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