RESUMO

Objetivou-se com o estudo investigar o efeito de diferentes osmolaridades do diluidor Triscitrato em espermatozóides epididimários de gatos domésticos (Feliscatus) e a congelação com glicerol ou etilenoglicol. Foram realizados dois experimentos, com 10 gatos. No Experimento 1, avaliou-se a manutenção dos parâmetros espermáticos em diluidor tris-citrato com osmolaridades 275, 325, 375, 425, 475 e 525mOsm, nos tempos (T0= 0, T1= 30 e T2= 60 min). No Experimento 2 a congelação foi realizada utilizando as osmolaridades 325 e 375 do glicerol a 4% ou etilenoglicol a 3%, 6%. Dentre as osmolaridades, quanto à motilidade a 325 mOsm não diferiu estatisticamente com o fluido epidídimal (controle) nos três tempos e a 375 mOsm no T0 e T1, e ambas não apresentaram diferenças estatísticas entre si e entre os tempos em todos os parâmetros espermáticos. O uso de 4% de glicerol em diluidor com 375 mOsm foi superior, apresentando motilidade de 25% ± 6, vigor 4, integridade de membrana plasmática de 48% ± 9, sem diferenças estatísticas com o resfriamento e na morfologia não foram encontradas diferenças estatísticas entre as duas osmolaridades. Portanto, o Tris-citrato com 325 e 375 mOsm entre as osmolaridades testadas e pós congelação com 375 mOsm e glicerol 4% manteve os parâmetros espermáticos.(AU)

The aim of this study was to investigate the effect of different osmotic potentials of Tris-citrate extender in epididymal spermatozoa of domestic cats (Felis catus), frozen with glycerol or ethyleneglycol. Two experiments were carried out, with ten cats. In the first experiment, the influence of extender with the osmolarityof 275, 325, 375, 425, 475 and 525 mOsm on sperm parameters were evaluated. In the second experiment, slow freezing was performed using glycerol at 4% or ethyleneglycolat 3% and 6% added to extender with 325and 375 mOsm. Among the osmolarities, the motilityat 325 mOsm did not differ statistically with epididymal fluid (control) at all times evaluated and at 375 mOsmat T0 and T1, and both showed no statistical differences between each other and between the times in all sperm parameters. Glycerol 4% added to extender with 475 mOsm was superior, presenting motilityof 25% ± 6, vigor 4, plasma membrane integrity of 48% ± 9, without statistical differences with cooling and in morphology, no statistical differences were found between the two osmolarities. Therefore, 325 and 375 mOsm Triscitrate between the osmolarities tested and after freezing with 375 mOsm and 4%, glycerol maintained the sperm parameters.(AU)

Assuntos

RESUMO

Objetivou-se com o estudo investigar o efeito de diferentes osmolaridades do diluidor Triscitrato em espermatozóides epididimários de gatos domésticos (Feliscatus) e a congelação com glicerol ou etilenoglicol. Foram realizados dois experimentos, com 10 gatos. No Experimento 1, avaliou-se a manutenção dos parâmetros espermáticos em diluidor tris-citrato com osmolaridades 275, 325, 375, 425, 475 e 525mOsm, nos tempos (T0= 0, T1= 30 e T2= 60 min). No Experimento 2 a congelação foi realizada utilizando as osmolaridades 325 e 375 do glicerol a 4% ou etilenoglicol a 3%, 6%. Dentre as osmolaridades, quanto à motilidade a 325 mOsm não diferiu estatisticamente com o fluido epidídimal (controle) nos três tempos e a 375 mOsm no T0 e T1, e ambas não apresentaram diferenças estatísticas entre si e entre os tempos em todos os parâmetros espermáticos. O uso de 4% de glicerol em diluidor com 375 mOsm foi superior, apresentando motilidade de 25% ± 6, vigor 4, integridade de membrana plasmática de 48% ± 9, sem diferenças estatísticas com o resfriamento e na morfologia não foram encontradas diferenças estatísticas entre as duas osmolaridades. Portanto, o Tris-citrato com 325 e 375 mOsm entre as osmolaridades testadas e pós congelação com 375 mOsm e glicerol 4% manteve os parâmetros espermáticos.

The aim of this study was to investigate the effect of different osmotic potentials of Tris-citrate extender in epididymal spermatozoa of domestic cats (Felis catus), frozen with glycerol or ethyleneglycol. Two experiments were carried out, with ten cats. In the first experiment, the influence of extender with the osmolarityof 275, 325, 375, 425, 475 and 525 mOsm on sperm parameters were evaluated. In the second experiment, slow freezing was performed using glycerol at 4% or ethyleneglycolat 3% and 6% added to extender with 325and 375 mOsm. Among the osmolarities, the motilityat 325 mOsm did not differ statistically with epididymal fluid (control) at all times evaluated and at 375 mOsmat T0 and T1, and both showed no statistical differences between each other and between the times in all sperm parameters. Glycerol 4% added to extender with 475 mOsm was superior, presenting motilityof 25% ± 6, vigor 4, plasma membrane integrity of 48% ± 9, without statistical differences with cooling and in morphology, no statistical differences were found between the two osmolarities. Therefore, 325 and 375 mOsm Triscitrate between the osmolarities tested and after freezing with 375 mOsm and 4%, glycerol maintained the sperm parameters.

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RESUMO

The efficiency of an alternative freezing protocol for goat embryos of different morphology and quality was tested. Fifty-eight embryos on Day 6-7 stage were transferred as fresh or after freeze-thawing (n=29/group). For freezing, embryos were placed into 1.5M ethylene-glycol solution for 10min. During this time, they were loaded in the central part of 0.25mL straw, separated by air bubble from columns containing PBS/BSA 0.4% plus 20% BFS. Straws were then frozen using a freezing machine from 20ºC to -6ºC at a cooling rate of 3ºC/min, stabilization for 15min (seeding after 5min), from -6 C to -32ºC at 0.6 C/min,and plunged into liquid nitrogen. Frozen embryos were thawed for 30s at 37ºC in a water bath. Embryos subjected to fresh transfer were maintained in holding medium (37ºC). Fresh and frozen-thawed embryos were transferred at day 7 post-estrus to 30 recipients. Kidding and kid born rates were similar (P> 0.05), respectively, for recipients receiving fresh (66.7% or 10/15; 55.2% or 16/29) or frozen-thawed (60% or 9/15; 51.7% or 15/29) embryos. The cryopreservation of goat embryos using slow-freezing protocol and 1.5MEG resulted in similar efficiency rates of fresh embryos.(AU)

Este estudo testou a eficiência de protocolo alternativo de criopreservação de embriões caprinos de diferentes qualidades morfológicas. Foram utilizados 58 embriões, coletados entre o sexto e o sétimo dia do ciclo estral (n=29/grupo). Embriões congelados passaram por solução 1,5M etilenoglicol por 10min e foram aspirados durante esse tempo para parte central de palheta 0,25mL, separada por bolhas de ar de colunas contendo PBS 0,4% BSA e 20% SFB. As palhetas foram congeladas em máquina de congelação de 20ºC a -6ºC, com taxa de resfriamento de 3ºC/min, estabilização por 15min (seeding após 5min), -6ºC a -32ºC a 0,6ºC/min, e imersas em nitrogênio líquido. Os embriões foram descongelados por 30s a 37ºC, em água. Embriões frescos foram mantidos em solução de manutenção (37ºC). Embriões frescos e congelados/descongelados foram transferidos para 30 receptoras no sétimo dia do ciclo estral. A taxa de partos e a de crias nascidas (respectivamente) foram similares (P>0,05) para receptoras recebendo embriões frescos (66,7% ou 10/15; 55,2% ou 16/29) ou congelados/descongelados (60,0% ou 9/15; 51,7% ou 15/29). O protocolo de criopreservação de embriões utilizado no presente estudo resultou em índices de eficiência semelhantes aos de embriões frescos.(AU)

Assuntos

RESUMO

The efficiency of an alternative freezing protocol for goat embryos of different morphology and quality was tested. Fifty-eight embryos on Day 6-7 stage were transferred as fresh or after freeze-thawing (n=29/group). For freezing, embryos were placed into 1.5M ethylene-glycol solution for 10min. During this time, they were loaded in the central part of 0.25mL straw, separated by air bubble from columns containing PBS/BSA 0.4% plus 20% BFS. Straws were then frozen using a freezing machine from 20ºC to -6ºC at a cooling rate of 3ºC/min, stabilization for 15min (seeding after 5min), from -6 C to -32ºC at 0.6 C/min,and plunged into liquid nitrogen. Frozen embryos were thawed for 30s at 37ºC in a water bath. Embryos subjected to fresh transfer were maintained in holding medium (37ºC). Fresh and frozen-thawed embryos were transferred at day 7 post-estrus to 30 recipients. Kidding and kid born rates were similar (P> 0.05), respectively, for recipients receiving fresh (66.7% or 10/15; 55.2% or 16/29) or frozen-thawed (60% or 9/15; 51.7% or 15/29) embryos. The cryopreservation of goat embryos using slow-freezing protocol and 1.5MEG resulted in similar efficiency rates of fresh embryos.(AU)

Este estudo testou a eficiência de protocolo alternativo de criopreservação de embriões caprinos de diferentes qualidades morfológicas. Foram utilizados 58 embriões, coletados entre o sexto e o sétimo dia do ciclo estral (n=29/grupo). Embriões congelados passaram por solução 1,5M etilenoglicol por 10min e foram aspirados durante esse tempo para parte central de palheta 0,25mL, separada por bolhas de ar de colunas contendo PBS 0,4% BSA e 20% SFB. As palhetas foram congeladas em máquina de congelação de 20ºC a -6ºC, com taxa de resfriamento de 3ºC/min, estabilização por 15min (seeding após 5min), -6ºC a -32ºC a 0,6ºC/min, e imersas em nitrogênio líquido. Os embriões foram descongelados por 30s a 37ºC, em água. Embriões frescos foram mantidos em solução de manutenção (37ºC). Embriões frescos e congelados/descongelados foram transferidos para 30 receptoras no sétimo dia do ciclo estral. A taxa de partos e a de crias nascidas (respectivamente) foram similares (P>0,05) para receptoras recebendo embriões frescos (66,7% ou 10/15; 55,2% ou 16/29) ou congelados/descongelados (60,0% ou 9/15; 51,7% ou 15/29). O protocolo de criopreservação de embriões utilizado no presente estudo resultou em índices de eficiência semelhantes aos de embriões frescos.(AU)

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RESUMO

TGF-ß1 is the main mediator of epithelial-to-mesenchymal transition (EMT). Hyperoxaluria induces crystalluria, interstitial fibrosis, and progressive renal failure. This study analyzed whether hyperoxaluria is associated with TGF-ß1 production and kidney fibrosis in mice and if oxalate or calcium oxalate (CaOx) could induce EMT in proximal tubule cells (HK2) and therefore contribute to the fibrotic process. Hyperoxaluria was induced by adding hydroxyproline and ethylene glycol to the mice's drinking water for up to 60 days. Renal function and oxalate and urinary crystals were evaluated. Kidney collagen production and TGF-ß1 expression were assessed. EMT was analyzed in vitro according to TGF-ß1 production, phenotypic characterization, invasion, cell migration, gene and protein expression of epithelial and mesenchymal markers. Hyperoxaluric mice showed a decrease in renal function and an increase in CaOx crystals and Ox urinary excretion. The deposition of collagen in the renal interstitium was observed. HK2 cells stimulated with Ox and CaOx exhibited a decreased expression of epithelial as well as increased expression mesenchymal markers; these cells presented mesenchymal phenotypic changes, migration, invasiveness capability and TGF-ß1 production, characterizing EMT. Treatment with BMP-7 or its overexpression in HK2 cells was effective at preventing it. This mechanism may contribute to the fibrosis observed in hyperoxaluria.

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RESUMO

The cryopreservation of testicular tissue is presented as the only alternative for the preservation of genetic material from prepubertal animals. However, this biotechnology is still being tested. The objective of this study was to evaluate the effect of different associations of cryoprotectants and the potential of cell proliferation after vitrification of testicular tissue of prepubertal cats. Five testicular pairs from five prepubertal cats were used, and each pair was divided into four fragments. Of these, one fragment composed of the control group (CG) and the rest were distributed in experimental groups according to the associations of cryoprotectants to be tested (dimethyl sulphoxide (DMSO)/glycerol (GLY); ethylene glycol (EG)/GLY) or DMSO/EG) in a final cryoprotectant concentration of 5.6 m. The fragments were submitted to vitrification, and after one week, fragments were heated and processed for histomorphological evaluation and quantification of nucleolar organizer regions (NORs). DMSO/GLY did not differ from CG and was superior to the other vitrified groups, as to cell separation and degree of shrinkage of the basal membrane. Concerning cell differentiation, visibility of the nucleus and nuclear condensation, all the vitrified groups were inferior to CG; however, DMSO/EG was inferior to DMSO/GLY and EG/GLY, which did not differ among themselves. CG was superior to all groups in quantification of NORs. DMSO/EG was inferior to all others, and there was no difference between DMSO/GLY and EG/GLY. The association DMSO/GLY presented the best preservation of tissue integrity and potential of cell proliferation after vitrification of the testicular tissue of prepubertal cats.

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RESUMO

We investigated the teratogenic effect of an ethylene glycol-methyl cellosolve mixture on gestating Wistar rats, that received a daily intraperitoneal dose of different concentration of the mixture on day 8 of gestation until day 20. Multivariate analysis and Post-Hoc Bonferroni tests were used and relative risk and attributable fraction were calculated. In rats treated with the mixture the number of live fetuses decreased and reabsorptions increased with increasing concentrations of the mixture, as well as the number of abnormal fetuses. Abnormalities consisted mainly in atypical craniofacial morphology, protruding tongue, edema, signs of growth delay and shorter limbs, their frequency and severity increased at higher concentrations of the mixture. We conclude that the ethylene glycol-methyl cellosolve mixture possesses a higher teratogenic potential than each of its constituents separately, producing external fetal abnormalities, growth delay, and increased fetal death.

Se investigó el efecto teratogénicos de una mezcla de etilenglicol y metilcelosolve en ratas gestantes, las cuales recibieron por vía intraperitoneal una dosis diaria, a diferentes concentraciones de la mezcla, del día 8 al día 20 de gestación. Se utilizaron las pruebas de análisis multivariado y Post-Hoc de Bonferroni, y se calcularon el riesgo relativo y la fracción atribuible. En las ratas tratadas con la mezcla el número de fetos vivos disminuyó y las reabsorciones y el número de fetos anormales aumentaron a mayor concentración de los solventes. Las anormalidades fetales consistieron principalmente en morfología atípica craneofacial, protrusión de la lengua, edema, signos de retraso de crecimiento y acortamiento de extremidades, y su frecuencia y severidad se incrementó a mayor concentración de la mezcla. Concluimos que la mezcla de etilenglicol-metilcelosolve tiene mayor efecto teratogénico que cuando actúan cada uno de los solventes por separado, produciendo anormalidades fetales externas, retraso del crecimiento y aumento de muerte fetal.

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