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Intracytoplasmic sperm injection (ICSI) in horses is currently employed for clinical and commercial uses, but the protocol could be optimized to improve its efficiency. We have hypothesized that destabilization of plasma and acrosomal membranes prior to injection would positively impact the developmental potential of equine zygotes generated by ICSI. This study evaluated effects of the sperm treatment with lysolecithin on plasma and acrosomal membranes and on oocyte activation ability, initially following heterologous ICSI on bovine oocytes and subsequently employing equine oocytes. The effects of the lysolecithin -treatment on the efficiency of conventional and piezo-assisted equine ICSI were evaluated. To do this, the equine sperm were treated with different concentrations of lysolecithin and the sperm plasma membrane, acrosome and DNA integrity were evaluated by flow cytometry. The results showed that a lysolecithin concentration of 0.08 % destabilized the membranes of all sperm and affected DNA integrity within the range described for the species (8-30 %). In addition, the heterologous ICSI assay showed that lysolecithin treatment was detrimental to the sperm's ability to activate the oocyte, therefore, chemical oocyte activation was used after equine ICSI after injection with lysolecithin -treated sperm. This group showed similar developmental rate to the control group with and without exogenous activation. In conclusion, lysolecithin pre-treatment is not necessary when using ICSI to produce equine embryos in vitro. The results from the current study provide additional insight regarding the factors impacting ICSI in horses.

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In assisted reproductive techniques, it is essential to perform a sperm selection to obtain spermatozoa with high motility and membrane integrity for in vitro fertilisation (IVF) and high-DNA integrity for intracytoplasmic sperm injection (ICSI). In this study, we evaluated whether Isolate® was a suitable substitute for Percoll® for assisted reproductive techniques. Commercial cryopreserved bovine semen was used after selection in both gradients, and plasma and acrosome membrane integrity, reactive oxygen species (ROS) levels, DNA integrity and mitochondrial membrane potential (ΔΨm) were assessed by flow cytometry. Motility parameters were also evaluated by CASA system. A similar percentage of spermatozoa with intact plasma membrane, acrosome integrity and high ΔΨm was observed in both sperm selection methods, but only Percoll® showed higher percentage of spermatozoa with intact plasma and acrosome membrane compared to the post-thawing group. No differences were observed in the motility, ROS, DNA fragmentation and on the in vitro embryo production in all experimental groups. In conclusion, the selection of bovine spermatozoa with Isolate® generates spermatozoa with similar quality parameters and embryonic development compared to Percoll® providing a suitable alternative sperm selection method for assisted reproductive techniques in this species.

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Intracytoplasmic sperm injection (ICSI) is an assisted reproduction tool with several applications. Its effectiveness in bovines is lower than that in other species, mainly because of difficulties in the decondensation of the sperm nucleus after injection, and the presence of the acrosome and the plasma membrane which remain intact in this procedure. In this study, we assessed the effect of lysolecithin (LL) and Triton X-100 (TX), in combination with glutathione (GSH) as sperm pretreatments prior to ICSI. The GSH-LL and GSH-TX groups showed 0% of spermatozoa with intact membrane (SYBR 14+/PI), in comparison with the control (63.3%) and GSH (65.7%) groups. The proportions of spermatozoa with damaged acrosome membrane in the GSH-LL, GSH-TX, GSH and control groups were 46%, 35.9%, 10.5% and 7.5%, respectively. Sperm chromatin decondensation analysis showed that the groups incubated for 3 hr with GSH presented greater decondensation (p < .05). Although fertilization was improved in all treatment groups evaluated, no differences were observed in the cleavage rate 72 hr after activation in the GSH (73.7%), GSH-LL (80.2%) and GSH-TX (77.8%) groups compared to the control (66.3%), neither in the blastocyst rate on day 8 (24.0%, 26.2%, 27.1% and 28.4% for the control, GSH, GSH-LL and GSH-TX groups, respectively). No differences were also observed in the total number of cells in all groups. In conclusion, although these sperm treatments promoted nuclear decondensation and induced plasma membrane disruption, these effects were not sufficient to improve bovine embryonic development after ICSI.

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Mammalian sperm undergo a series of biochemical transformations in the female reproductive tract that are collectively known as capacitation. Cyclodextrins added to the sperm culture medium have been described to induce in vitro sperm capacitation, enabling its use in protein-free media. However, the additive capacitating effect of methyl-ß-cyclodextrin (MßCD) in the medium containing bovine serum albumin (BSA) is unknown in the bovine species. In this study, we evaluated the effects of incubating frozen-thawed bovine spermatozoa in a BSA-containing medium supplemented with MßCD on different sperm quality and functional parameters. Sperm viability decreased with the addition of MßCD in a dose-dependent manner (p < 0.05), and DNA damage could be observed but only with the highest concentration of MßCD. However, pre-incubation of spermatozoa in MßCD-supplemented medium improved the capacitation status as assessed by the increase in plasma membrane fluidity, intracellular calcium concentration, induced acrosome reactivity and zona pellucida (ZP)-binding ability (p < 0.05). Thus, we conclude that MßCD supplementation is able to enhance the capacitation status of frozen-thawed bovine spermatozoa cultured in capacitation medium containing BSA and could result in a valid strategy for its application on artificial reproductive technologies such as in vitro fertilization or intracytoplasmic sperm injection.

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The purpose of the study was to evaluate the "lato sensu" graduate programs of study of the Department of Nursing in the UFRN, and to know the perspectives of its students and faculty. A total of 67 questionnaires were applied to 14 professors and 53 ex-students. The sources of data were: a survey of the scientific knowledge produced by the faculty; specialization program final reports; partial 1989-1991 program evaluations; and, the final report of the first Graduate Program Evaluation Seminar (1992). Eventhough the results of the evaluation were positive, some aspects of the program were found to need further analysis so that future graduate studies might be improved. These aspects were: revision of the curriculum content, improvement of the space environment, and improvement of the bibliographic resources.

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La enfermedad venosa de los miembros inferiores es una patología bastante frecuente en nuestra población, la cual eleva significativamente la tasa de morbilidad de als enfermedades cardiovasculares; debido a su cronicidad, induce a serios problemas y a un entorno patológico amplio incluyendo costo sociales, familiares y económicos altos. Han sido ensayados múltiples farmacos en el tratamiento de esta enfermedad, con resultados variables. Ultimas investigaciones señalan que la "Diosmina" es un medicamento con notables efectos benéficos sobre las flebopatias; debido a ello se realizó este estudio prospectivo Clínicoterapéutico a doble ciego, en el Hospital Nacional Edgardo Rebagliati Martins (IPSS) Consultorio No. 55, de enero a mayo de 1992. De 100 pacientes incluidos en el estudio, 50 recibieron Diosmina y otros tantos- Diosmina placebo, la dosis administrada a los pacientes fue 1 capsula cada 12 horas (600mg por día). La mayoria de pacientes fueron mujeres (81 por ciento) con edad promedio de 45 años. Los hallazgos clínicos más importantes fueron: dilataciones venosas, edema, dolor, ardor y pesadez de miembros inferiores. Ambas drogas fueron muy bien toleradas. Con la droga "A" se obtuvo una mejoria de los síntomas en un 78 por ciento, a los 30 días, 95 por ciento, a los 60 días y 97 por ciento a los 90. Con la droga "B" solo se obtuvo una mejoria de los sintomas de un 25 por ciento a los 30 días(p menor de 0.001), no modificandose dicha respuesta a los 60 y 90 días. Nuestros resultados corroboran la eficacia de la Diosmina (Droga "A") en el tratamiento de la Insuficiencia Periférica Vascular Venosa

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Se trata de un estudio retrospectivo de 916 pacientes con el diagnóstico presuntivo de apendicitis aguda que fueron sometidos a tratamiento quirúrgico. Se analizaron los datos de la anamnesis, examen clínico, exámenes auxiliares y hallazgos anatomopatológicos

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