Involvement of the food industry in nutrition conferences in Latin America and the Caribbean.

OBJECTIVE: Identify and characterise the food industry's involvement in nutrition and dietetics national and regional events in Latin America and the Caribbean. DESIGN: Between February and April 2020, we conducted desk-based searches for nutrition and dietetics events held in the region between January 2018 and December 2019. Online freely accessible, publicly available information was collected on the involvement of the food industry through: sponsorship of events; sponsorship of sessions; speakers from the food industry; scholarships, fellowship, grants, awards and other prizes and; exhibition space/booths. SETTING: Nutrition and dietetics events in Latin America and the Caribbean. RESULTS: Thirty-one events held in twenty countries of the region had information publicly available online at the period of data collection. There was a lack of transparency on the involvement of industry actors in these events. When information was publicly available, we found that a total of ninety-two food industry actors sponsored 88 % of these events. CONCLUSIONS: There is a mostly unreported, but likely extensive, involvement of food industry actors in nutrition and dietetics events in Latin America and the Caribbean.

Reflexiones sobre la ética de la investigación en Colombia / Reflections on Ethics of Research in Colombia

Resumen Se reflexiona en torno al diseño normativo que regula la investigación en Colombia y las prácticas de los investigadores desde un enfoque ético, abordando asuntos pro blemáticos en las ciencias de la salud, las ciencias sociales y las disciplinas ambien tales, para concluir que se necesita fortalecer el control del Estado en estos temas, la actualización de la normatividad y una mayor formación de los investigadores y miembros de Comités de Ética en investigación, especialmente en: la protección de los participantes, el cuidado de los animales, los conflictos de interés, el manejo de comunidades y de grupos vulnerables, los protocolos comunitarios, el consentimien to informado, la consulta previa, el cuidado de la biodiversidad y el acceso a recursos genéticos.

Abstract This paper reflects on the normative design, which regulates research in Colombia and the practices of researchers from an ethical approach, by addressing critical issues in the health sciences, social sciences, and environmental disciplines, to conclude that it is necessary to strengthen state control in these issues, the updating of the regulations and greater training of researchers and members of Ethics Committees in research , especially in the protection of participants, animal care, conflicts of interest, the management of communities, and vulnerable groups, community pro tocols, informed consent, prior consultation, biodiversity care, and access to genetic resources.

Evaluation of the Stability of Fatty Acids in Erythrocytes from Human Umbilical Cord.

The interest in the amount of polyunsaturated fatty acids (PUFA) in the umbilical cord blood (UCB) is increasing, but the stability of erythrocyte PUFA in these samples during storage and washing of the erythrocytes has not been directly evaluated. The purpose of this study was to analyze the effect of the lapse of time on the fatty acid (FA) content from UCB sample collection and maintained at 4 °C (0-12 h) until erythrocyte separation and washing. Palmitic acid (16:0), stearic acid (18:0), 18:1n-7/n-9, linoleic acid (18:2n-6), arachidonic acid (20:4n-6), 22:4n-6, eicosapentaenoic acid (20:5n-3), docosapentaenoic acid (22:5n-3), and docosahexaenoic acid (22:6n-3) together accounted for 87% of the FA profile in the umbilical vein erythrocytes. No difference was observed in the concentration of any of the FA studied, nor in the sum of saturated fatty acids (SFA), PUFA, or LC-PUFA in umbilical erythrocytes obtained at delivery and stored up to 12 h before the separation of erythrocytes. However, if a washing step was included in the processing of the erythrocytes, a decrease in the concentration of 16:0, 18:0, 18:3n-3, 20:4n-6, 22:4n-6, total SFA, PUFA, LC-PUFA, and n-6 LC-PUFA was evidenced, compared to unwashed erythrocytes. The FA concentration in umbilical cord erythrocytes did not change between samples stored from 0 to 12 h until erythrocyte separation. Erythrocyte washing before storage decreased the concentration of significant individual and total SFA, PUFA, and LC-PUFA. These results should be considered when planning the collection of UCB samples for the study of fatty acid concentration due to the nonscheduled timing of deliveries.

Involvement of the food industry in nutrition conferences in Latin America and the Caribbean

Objective: Identify and characterise the food industry's involvement in nutrition and dietetics national and regional events in Latin America and the Caribbean. Design: Between February and April 2020, we conducted desk-based searches for nutrition and dietetics events held in the region between January 2018 and December 2019. Online freely accessible, publicly available information was collected on the involvement of the food industry through: sponsorship of events; sponsorship of sessions; speakers from the food industry; scholarships, fellowship, grants, awards and other prizes and; exhibition space/booths. Setting: Nutrition and dietetics events in Latin America and the Caribbean. Results: Thirty-one events held in twenty countries of the region had information publicly available online at the period of data collection. There was a lack of transparency on the involvement of industry actors in these events. When information was publicly available, we found that a total of ninety-two food industry actors sponsored 88 % of these events. Conclusions: There is a mostly unreported, but likely extensive, involvement of food industry actors in nutrition and dietetics events in Latin America and the Caribbean.(AU)

Pectin Esterification Degree in the Bioavailability of Non-heme Iron in Women.

Pectins are a type of soluble fiber present in natural and processed foods. Evidence regarding the effect of esterification degree of pectins on iron absorption in humans is scarce. In the present study, the effect of pectins with different degrees of esterification on non-heme iron absorption in women was evaluated. A controlled experimental study was conducted with block design, involving 13 apparently healthy, adult women. Each subject received 5 mg Fe (FeSO4) without pectin (control) or accompanied by 5 g citrus pectin, two with a low degree of esterification (27 and 36%), and one with a high degree of esterification (67 to 73%), each on different days. Each day, the 5 mg Fe doses were marked with radioactive 59Fe or 55Fe. Radioactivity incorporated into erythrocytes was determined in blood samples 14 days after the marked Fe doses were consumed. On days 18 and 36 of study, 30 and 20 mL blood samples were obtained, respectively, and blood sample radioactivity incorporated into erythrocytes was determined. Body iron status was determined from blood taken on day 18. Whole body blood volume was estimated for calculate iron bioavailability; it was assumed that 80% of absorbed radioactivity was incorporated into the Hb. All women participants signed an informed consent of participation at baseline. Iron bioavailability (mean geometric ±1 SD) alone (control) was 18.2% (12.3-27.1%), iron + pectin27 was 17.2% (10.2-29.2%), iron + pectin36 was 15.3% (9.5-24.6%), and iron + pectin67 was 19.5% (10.0-38.0%). No statistically significant differences between iron bioavailability (repeated measures ANOVA, p = 0.22) were observed. Pectin esterification degree does not influence the bioavailability of non-heme iron in women.

Effect of phytic acid, tannic acid and pectin on fasting iron bioavailability both in the presence and absence of calcium.

OBJECTIVE: To determine the effect of phytic acid, tannic acid and pectin on fasting non-heme iron bioavailability in both the presence and absence of calcium. RESEARCH METHODS: Twenty-eight apparently healthy adult females participated in two iron absorption studies using radioactive iron isotopes ((59)Fe and (55)Fe). One group received 5mg of iron (as FeSO4) alone (control), together with 10mg of phytic acid, 100mg of tannic acid and 250mg of pectin (study A), on different days. The second group received the same iron doses and compounds as the other group, plus 800mg of calcium (CaCl2) (study B). The compounds were administered after an overnight fast, and no food or beverages were consumed for the following 3h. Iron status and circulating radioactivity were measured in venous blood samples. RESULTS: The geometric means of iron bioavailability (range±1SD) for iron alone, iron with phytic acid, iron with tannic acid, and iron with citrus pectin were 25.0% (11.9-52.0); 18.9% (9.9-35.8); 16.8% (8.7-32.3); and 21.1% (10.2-43.9), respectively (repeated-measures ANOVA, p<0.02 (Dunnett's post hoc: control vs tannic acid p<0.05). When 800mg of calcium was added (study B), iron bioavailability was 16.7% (10.1-27.5); 13.2% (7.1-24.6); 14.8% (8.8-25.1); and 12.6% (5.5-28.8), respectively (repeated-measures ANOVA, NS). CONCLUSIONS: Tannic acid decreases the fasting bioavailability of non-heme iron, however this effect did not exist in the presence of calcium. No effect was observed by phytic acid or citrus pectin on fasting non-heme iron bioavailability in both the presence and absence of calcium.

Effects of spermicidal extracts of Ananas comosus (pineapple) and Sapindus saponaria (jaboncillo) on cell viability, cytotoxicity and apoptosis / Efecto del extracto espermicida de Ananas comosus y Sapindus saponaria sobre la viabilidad, la citotoxicidad y la apoptosis celular

Introduction: there are natural products from different fruits and plants that are effective as spermicides, but it is important that they should have little or no cytotoxic effect on epithelial cells. Currently available spermicides with nonoxynol-9 cause vaginal irritation and damage to the vaginal mucosa, the uterine epithelium, and the microbial flora of the vagina. Objective: to elucidate the effect on cell viability, cytotoxicity and apoptosis of spermicidal extracts of Ananas comosus (L.) Merr. and Sapindus saponaria L. over HeLa cell line. Methods: both extracts were evaluated on HeLa cell line using the novel ApoTox-Glo™ Triplex Assay to determine whether cell viability, cytotoxicity and apoptosis were affected. Results: it was determined that treatment with Sapindus saponaria and Ananas comosus extracts initially affected cell viability, but the latter tended to be restored. There was a sign of cell apoptosis that also tended to decrease over time. Conclusions: extracts of Sapindus saponaria and Ananas comosus may affect the survival of cells at the beginning, but these can continue replicating over time. There was a sign of cell apoptosis that also tended to decrease over time. Something similar happened to cell cytotoxicity, indicating that although the extracts may affect the survival of cells at the beginning (6 hours of treatment), these can continue dividing over time.

Introducción: diversos compuestos de procedencia natural como frutos y plantas son altamente efectivos como espermicidas, pero es necesario que estos no tengan efecto citotóxico sobre las células epiteliales. Los espermicidas disponibles actualmente sobre la base de nonoxinol-9, causan irritación y daño en la mucosa, el epitelio uterino y la flora microbiana de la vagina. Objetivo: determinar el efecto sobre la viabilidad, citotoxicidad y apoptosis celular de extractos con actividad espermicida de Ananas comosus (L.) Merr. y Sapindus saponaria L. sobre la línea celular HeLa. Métodos: ambos extractos se evaluaron sobre la línea celular HeLa para determinar el efecto en la viabilidad, la citotoxicidad y la apoptosis celular, utilizando el novedoso ensayo triple ApoTox-Glo™. Resultados: inicialmente el tratamiento con los extractos de Sapindus saponaria y Ananas comosus afectaron la viabilidad celular; sin embargo, esta tendió a restablecerse y mantenerse en el tiempo. Asimismo, la señal de apoptosis celular tendió a disminuir a través de los tiempos de tratamiento. Conclusiones: los extractos de Sapindus saponaria y Ananas comosus podrían afectar la viabilidad celular inicialmente; sin embargo, estas continúan incrementándose con el paso del tiempo. Al mismo tiempo la señal de apoptosis celular disminuyó a través del tiempo y algo similar sucedió con la citotoxicidad celular, indicando que con el paso de las horas los extractos pueden afectar la proliferación celular al inicio (6 h de tratamiento), pero continúan proliferando.

Expresión del fenotipo Duffy negativo en mujeres afrodescendientes y su relación con la preeclampsia / Expression of the Duffy negative phenotype in women of African descent and their relation to pre-eclampsia

La preeclampsia (PE) es una complicación del embarazo que trae consigo algunas consecuencias negativas para la madre y el feto: en la madre provoca principalmente hipertensión y proteinuria, mientras que en el feto puede presentarse trombocitopenia, alteración en el desarrollo del sistema nervioso central y circulatorio, y restricción del crecimiento intrauterino, lo cual se considera el factor de riesgo principal de muerte fetal en nacimientos producto de una PE severa. En la preeclampsia se presenta una disfunción endotelial relacionada con placentación anormal, estado de estrés oxidativo y proceso inflamatorio sistémico, que lleva a la activación de neutrófilos y monocitos. Se ha considerado a la interleucina-8 (IL-8) como un posible candidato desencadenante por ser quimioatrayente y activador de leucocitos; en la circulación sanguínea, la IL-8 se une a un receptor de quimiocina multiespecífico de alta afinidad denominado DARC, que es idéntico al antígeno del grupo sanguíneo Duffy. Este receptor regula los niveles plasmáticos de IL-8, uniéndose a esta quimiocina, pero cuando hay una mutación en la región promotora del gen se altera la expresión de DARC, lo que conlleva a que la IL-8 de los factores genéticos involucrados en la activación de los neutrófilos y de los monocitos, y por ende, en la disfunción endotelial presentada durante este síndrome hipertensivo, especialmente en la población afrodescendiente.

Preeclampsia (PE) is a complication of pregnancy that brings some negative consequences for both mother and fetus. It specially causes hypertension and proteinuria in mothers; while in fetuses it causes thrombocytopenia, development alterations of the central nervous and circulatory system; also intrauterine growth restriction may occur. This last factor is regarded as the main risk factor for fetal death in births as a result of severe PE. There is endothelial dysfunction in preeclampsia related to abnormal placentation, state of oxidative stress and systemic inflammatory process that leads to the activation of neutrophils and monocytes. Interleukin-8 (IL-8) is considered as a possible trigger candidate, since this chemokine is a chemoattractant and leukocyte activator. In the bloodstream, interleukin-8 binds to a high affinity multispecific-chemokine receptor called DARC, which is identical to the Duffy blood group antigen. This receptor regulates plasma levels of IL-8 by binding to chemokine. But, when there is a mutation in the gene promoter region, DARC expression is altered, and IL-8 inefficiently binds to receptor. This mutation results in Duffy negative phenotype, which is present in most of African descendants. This literature review is intended to address the role of IL-8 as neutrophil chemo-attractant, the importance of Duffy blood system and the possible association between ethnicity and preeclampsia.

Alergia al semen / Semen allergy

La alergia al semen comprende una variedad de síntomas tanto locales como sistémicos causados por reacciones de hipersensibilidad inmediata y caracterizados por títulos elevados de IgE. El objetivo de este estudio es describir el caso de una paciente con alergia al semen: mujer de 21 años de edad que presenta ardor y sensación de quemazón en el área genital luego de tener contacto con el semen de su pareja. El análisis seminal del compañero sexual no presenta ningún tipo de alteración. Los síntomas desaparecen con el uso de condón o con la práctica del coito interrumpido. La alergia al semen es una alteración, que si bien es poco frecuente, puede afectar los deseos de concepción de las mujeres que la presentan, es un fenómeno poco estudiado por lo que se requieren más reportes para su caracterización.

Semen allergy includes several local and systemic symptoms caused by immediate hypersensitivity reactions and it is characterized by high levels of IgE. The objective of this study was to describe the case of a patient with semen allergy. A 21 year-old woman experienced itching and burning sensation in the genital area after contact with the semen of her sexual partner. Semen analysis was normal. Symptoms disappear with the use of condom or the practice of coitus interruptus. Semen allergy is a condition, although rare, can affect the desire of conceiving in women who suffers it. It is a briefly studied phenomenon which requires more reports for proper characterization.

Lipoxinas inducidas por la aspirina: una alternativa para modular los procesos proinflamatorios en la preeclampsia / Aspirin induced lipoxins: alternative to modulate proinflammatory processes in preeclampsia

La preeclampsia es un síndrome hipertensivo que se presenta a partir de la semana 20 de gestación. El objetivo de este trabajo es describir la producción y los mecanismos de acción de las lipoxinas inducidas por la aspirina y proponerlas como una alternativa adecuada para modular los procesos oxidativos característicos de la preeclampsia y los ciclos proinflamatorios que inician con la cascada de activación del factor nuclear-kappa B, y en consecuencia de sus productos. La preeclampsia se caracteriza por la producción de sustancias proinflamatorias, que inducen la activación de células endoteliales, directa o indirectamente, a través de la activación previa de los monocitos, los cuales pueden generar especies reactivas de oxígeno y expresar moléculas de adhesión que median la interacción con el endotelio, contribuyendo a su estado de disfunción, activación e inducción de la cascada de señalización del factor nuclear-kappa B. La aspirina por su parte, induce la producción de lipoxinas que inhiben la activación del factor nuclear-kappa B mediante el bloqueo de la proteína quinasa IkB, necesaria para desencadenar la activación de la vía canónica y no canónica de este factor nuclear.

Preeclampsia is a hypertensive syndrome that occurs after the 20th weeks of gestation. The objective of this review was to describe the mechanisms of production and action of aspirin- triggered lipoxins in order to consider them as a suitable alternative to modulate oxidative processes, which are characteristic of preeclampsia and proinflammatory cycles starting with cascade activation of nuclear factor-kappa B, consequently of their products. Preeclampsia is characterized by the production of proinflammatory substances that induce directly or indirectly endothelial cell activation,, through prior activation of monocytes, which can generate reactive oxygen species and expression of adhesion molecules that mediate interacting with the endothelium, contributing to its dysfunction, activation and induction of signaling cascade nuclear factor-kappa B. Aspirin induces lipoxin, which inhibits the activation of nuclear factor-kappa B by blocking IkB protein kinase, necessary to trigger the activation of canonical and non-canonical pathway of this nuclear factor.

Actividad espermicida y citotóxica del extracto de Sapindus saponaria L. (jaboncillo) / Evaluation of the spermicidal and cytotoxic activity of extracts of Sapindus saponaria L. (jaboncillo)

Introducción: los espermicidas están entre los métodos anticonceptivos que pueden inmovilizar o matar los espermatozoides. Objetivo: evaluar la actividad espermicida y citotóxica de los extractos de Sapindus saponaria L., conocida como jaboncillo, sobre espermatozoides humanos y la línea celular HeLa, respectivamente. Métodos: las muestras de semen donadas por individuos sanos se incubaron con los extractos de Sapindus saponaria L. y sus respectivas fracciones. La movilidad y la viabilidad espermática se evaluó antes y después de cada tratamiento. Adicionalmente, el efecto citotóxico del extracto se valoró sobre la línea celular HeLa mediante el ensayo 3-(4,5 dimetiltiazol-2-il)-5-(3-carboximetoxifenil)-2-(4-sulfofenil)-2H-tetrazolio (MTS). Resultados: el máximo efecto espermicida se observó cuando las muestras de semen se incubaron con la fracción polar del extracto de hojas de Sapindus saponaria L., luego de 5 min de tratamiento (p< 0,05). No se encontró efecto citotóxico en la línea celular HeLa luego de 6 y 12 h de tratamiento con la fracción polar del extracto de hojas. Conclusión: el extracto de Sapindus saponaria L. puede ser una nueva opción como espermicida con menos efectos adversos.

Introduction: spermicides are contraceptive methods aimed at either immobilizing or killing spermatozoa. Objective: evaluate the spermicidal and cytotoxic activity of extracts of Sapindus saponaria L. (jaboncillo) on human spermatozoa and the HeLa cell line, respectively. Methods: semen samples from healthy individuals were incubated with extracts of Sapindus saponaria L. and their fractions. Sperm motility and viability were measured before and after each treatment. Additionally, the cytotoxic effect of the extract on the HeLa cell line was assessed by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy methoxy phenyl)-2-(4-sulfophenyl)-2H-tetrazolium MTS assay. Results: maximum spermicidal effect was observed when semen samples were incubated with the polar fraction of Sapindus saponaria L. leaf extract after 5 minutes of treatment (p< 0.05). No cytotoxic effect on the HeLa cell line was found after 6 and 12 hours of treatment with the polar fraction of the leaf extract. Conclusion: the extract of Sapindus saponaria L. may be a new spermicidal option with fewer adverse effects.

Sacrificio y negociación: Algunos obstáculos subjetivos a las conquistas feministas / Sacrifice and negotiation: Some subjective obstacles to the feminist conquest / Sacrifice et negociation. quelques obstacles subjectifs aux conquetes feministes

Algunas mujeres feministas escuchadas en con-sulta, se encuentran con que hay un obstáculo subjetivo para ejercer los derechos que han con-quistado, una investigación al respecto y publica-da como libro: Feminidades, sacrificio y negocia-ción en el tiempo de los derechos revela que más allá de los condicionamientos culturales del patriarcado, estas mujeres deben resolver un asunto con su superyó femenino para salir de este impasse. El presente artículo es una refle-xión-síntesis de dicha investigación.

Some feminist women seen in consultation, find a subjective obstacles to the feminism conquest; one research about that matter and published as the book: Femininities, sacrifice and negotiation in the time of rights reveals that beyond the cul-tural conditioning of the patriarchy, these women have to solve an issue with their feminine supere-go to overcome this impasse. This article is a reflection-synthesis of such research.

Certaines femmes féministes entendues en con-sultation se trouvent avec un obstacle subjectif pour exercer leur droit qu’elles ont conquis. Une recherche sur ce sujet, publiée et un livre publié sous le titre: Feminités, sacrifice et négociation dans le temps des droits démontre qu’au-delà des conditionnements culturels du patriarcat, ces femmes doivent résoudre une affaire avec leur supermoi afin de sortir de cette impasse. Cet article est une réfléction-synthèse de cette re-cherche.

The effects of male age on semen parameters: analysis of 1364 men attending an andrology center.

Although the effect of maternal age on fertility is well known, it is unclear whether paternal age also affects fertility. The aim of this retrospective study was to establish an association between the age of the individuals from Medellin, Colombia with semen volume, rapid progressive motility (a), total progressive motility (a + b) and concentration. We evaluated semen volume using a graduated tube, progressive motility using light microscopy (40 x) and sperm concentration using a Makler Chamber. Semen samples were grouped according to age into three arbitrary groups (or= to 40 years). The semen volume, rapid progressive motility (a) and total progressive motility (a + b), concentration and total sperm count were found to be inversely related to age (p < 0.05). The reduction in semen parameters of 1364 men attending an andrology center was associated with increasing age of the individuals.

The dynamics of fluorescently labeled endogenous gurken mRNA in Drosophila.

During Drosophila oogenesis, the targeted localization of gurken (grk) mRNA leads to the establishment of the axis polarity of the egg. In early stages of oogenesis, grk mRNA is found at the posterior of the oocyte, whereas in the later stages grk mRNA is positioned at the dorsal anterior corner of the oocyte. In order to visualize the real-time localization and anchorage of endogenous grk mRNA in living oocytes, we have utilized the MS2-MCP system. We show that MCP-GFP-tagged endogenous grk mRNA localizes properly within wild-type oocytes and behaves aberrantly in mutant backgrounds. Fluorescence recovery after photobleaching (FRAP) experiments of localized grk mRNA in egg chambers reveal a difference in the dynamics of grk mRNA between young and older egg chambers. grk mRNA particles, as a population, are highly dynamic molecules that steadily lose their dynamic nature as oogenesis progresses. This difference in dynamics is attenuated in K10 and sqd(1) mutants such that mislocalized grk mRNA in older stages is much more dynamic compared with that in wild-type controls. By contrast, in flies with compromised dynein activity, properly localized grk mRNA is much more static. Taken together, we have observed the nature of localized grk mRNA in live oocytes and propose that its maintenance changes from a dynamic to a static process as oogenesis progresses.

[Early embryo death: does the male factor play a role?]. / Muerte embrionaria temprana: tiene influencia el factor masculino?

OBJECTIVE: To discuss the possible role of the male factor in early embryo death. METHOD: A detailed bibliographic review has been put together to establish which alterations in spermatozoa can be associated with early embryo death. RESULTS: Before the fusion between plasma membranes of the sperm and the oocyte occurs, both germ cells must undergo a maturation process that allows successful fertilization and embryo development. The study of couples with early embryo loss is usually approached from the side of the woman due to the obvious relationship that exists between the female and the developing embryo. However, it is not illogical to suppose that a genetic or epigenetic alteration of the sperm could have important consequences on these losses due to the necessary contribution of the male gamete not only to embryonic but also to placental development. On the other hand, spermatozoa have certain characteristics such as a highly compact DNA, they undergo apoptosis and the seminal plasma contains antioxidants that protect the structural and functional integrity of the germ cell. These factors assure fertilization and embryo development. Nevertheless, epigenetic alterations of the sperm such as altered chromatin packing, mistakes in imprinting, absence or alteration of the centrosome, telomeric shortening and absence of sperm RNA, could affect functions leading to early embryo loss. CONCLUSIONS: Knowledge concerning sperm intervention previous to embryo development will provide the basis for better understanding and for possible diagnosis and treatment of diverse reproductive alterations in men that could impede embryo development.

Muerte embrionaria temprana: ¿tiene influencia el factor masculino? / Early embryo death: does the male factor play a role?

Objetivo: Discutir el efecto que puede tener el factor masculino sobre la muerte embrionaria temprana. Método: Se hace una revisión de literatura de diferentes componentes del espermatozoide que pueden tener algún papel en la muerte embrionaria temprana. Resultados: Antes que ocurra la fusión entre la membrana plasmática del espermatozoide y la del oocito, ambos gametos deben sufrir un proceso de maduración que permita la fecundación y el desarrollo embrionario exitosos. El estudio de las parejas con muerte embrionaria temprana, usualmente se aborda desde el factor femenino por la obvia relación de la mujer con su producto en desarrollo, pero no es ilógico suponer que una alteración genética o epigenética en el espermatozoide, tenga un papel importante en estas pérdidas por su importancia en el desarrollo placentario y embrionario. El espermatozoide posee algunas características como el empaquetamiento del ADN, la apoptosis y los antioxidantes en el plasma seminal, que protegen la integridad estructural y funcional de la célula germinal, permitiendo que el espermatozoide fecunde al oocito y contribuya al desarrollo embrionario. Sin embargo, alteraciones epigenéticas como el remodelamiento de la cromatina y la consecuente perturbación de los eventos relacionados con la impronta genómica podrían ser causas de origen paterno que pueden tener alguna representación en las muertes embrionarias tempranas como también lo son la ausencia o alteración del centrosoma, el acortamiento telomérico y la ausencia de RNA espermático. Conclusiones: El conocimiento de la intervención espermática en el desarrollo embrionario proporcionará bases para el entendimiento y el posible diagnóstico y tratamiento de diversas alteraciones reproductivas masculinas que puedan estar ocasionando fallas en el desarrollo posterior del embrión (AU)

Objective: To discuss the possible role of the male factor in early embryo death. Method: A detailed bibliographic review has been put together to establish which alterations in spermatozoa can be associated with early embryo death. Results: Before the fusion between plasma membranes of the sperm and the oocyte occurs, both germ cells must undergo a maturation process that allows successful fertilization and embryo development. The study of couples with early embryo loss is usually approached from the side of the woman due to the obvious relationship that exists between the female and the developing embryo. However, it is not illogical to suppose that a genetic or epigenetic alteration of the sperm could have important consequences on these losses due to the necessary contribution of the male gamete not only to embryonic but also to placental development. On the other hand, spermatozoa have certain characteristics such as a highly compact DNA, they undergo apoptosis and the seminal plasma contains antioxidants that protect the structural and functional integrity of the germ cell. These factors assure fertilization and embryo development. Nevertheless, epigenetic alterations of the sperm such as altered chromatin packing, mistakes in imprinting, absence or alteration of the centrosome, telomeric shortening and absence of sperm RNA, could affect functions leading to early embryo loss. Conclusions: Knowledge concerning sperm intervention previous to embryo development will provide the basis for better understanding and for possible diagnosis and treatment of diverse reproductive alterations in men that could impede embryo development (AU)

Functional evaluation of sperm in Colombian fertile men.

OBJECTIVE: The aim of the present study was to evaluate in 111 ejaculates from fertile men membrane integrity of spermatozoa before selection and sperm motility, and sperm concentration and chromatin integrity before and after selection of motile spermatozoo. METHODS: We evaluated the membrane integrity (using hypoosmotic swelling test and Eosin-Y) before separation and chromatin integrity (using acridine orange), concentration and motility before and after separation by migration sedimentation technique. All individuals had pregnant wives or had procreated a baby during the last year. RESULTS: The data of sperm membrane integrity by the eosin-Y and hypoosmotic swelling tests did not show significant statistical differences and the correlation between them was low. The percentage of motile sperm (grades a + b) increased from 57% to 87% (p < 0.001), the concentration decreased from 89 to 31 x 10(6) sperm/ mL (p < 0.001) and chromatin integrity increased significantly (p < 0.0001) after separation of semen. CONCLUSIONS: The great variation in the values obtained in the functional test in fertile males requires a re-evaluation of the use of these tests in clinical practice of infertility.

Evaluación funcional del esperma en varones fértiles columbianos / Functional evaluation of sperm in colombian fertile men

OBJETIVO: El fin del presente estudio fue evaluar en 111 eyaculados de individuos fértiles la integridad de la membrana de los espermatozoides antes de la selección, y la movilidad, la concentración, la integridad de la cromatina antes y después de la selección espermática. MÉTODOS: Evaluamos la integridad de la membrana (usando la prueba de hinchazón hipoosmotica y eosina Y) antes de la selección, y la integridad de la cromatina (usando naranja de acridina) concentración y movilidad antes y después de la separación mediante la técnica de migración sedimentación. RESULTADOS: Los datos de la integridad de la membrana espermática mediante la prueba de hinchazón hipoosmótica y eosina Y no mostraron diferencias estadísticamente significativas y la correlación entre estas fue baja. El porcentaje de espermatozoides móviles (grado a + b) se incrementó de 57% a 87% (p < 0.001), la concentración disminuyó de 89 a 31 x 106 espermatozoides/ mL (p < 0.001) y la integridad de la cromatina se incrementó significativamente (p < 0.0001) antes y después de la separación. CONLCUSIONES: la gran variación en los valores obtenidos en las pruebas funcionales en hombres fértiles requiere una re-evaluación del uso de estas pruebas en la práctica clínica de infertilidad

OBJECTIVE: The aim of the present study was to evaluate in 111 ejaculates from fertile men membrane integrity of spermatozoa before selection and sperm motility, and sperm concentration and chromatin integrity before and after selection of motile spermatozoa. METHODS: We evaluated the membrane integrity (using hypoosmotic swelling test and Eosin-Y) before separation and chromatin integrity (using acridine orange), concentration and motility before and after separation by migration sedimentation technique. All individuals had pregnant wives or had procreated a baby during the last year. RESULTS: The data of sperm membrane integrity by the eosin-Y and hypoosmotic swelling tests did not show significant statistical differences and the correlation between them was low. The percentage of motile sperm (grades a + b) increased from 57% to 87% (p < 0.001), the concentration decreased from 89 to 31 x 106 sperm/mL (p < 0.001) and chromatin integrity increased significantly (p < 0.0001) after separation of semen. CONCLUSIONS: The great variation in the values obtained in the functional test in fertile males requires a re-evaluation of the use of these tests in clinical practice of infertility

Expression and function of variants of slob, slowpoke channel binding protein, in Drosophila.

Slob binds to and modulates the Drosophila Slowpoke (dSlo) calcium-activated potassium channel and also recruits the ubiquitous signaling protein 14-3-3 to the channel regulatory complex. RT-PCR reveals the presence of multiple slob transcripts in Drosophila heads. The transcripts are predicted to encode proteins that we call Slob51 (kDa), Slob57, Slob65, and Slob71. Slob51 and Slob65 are splice variants that lack a motif important for the binding of 14-3-3. Previous microarray analyses demonstrated the circadian cycling of slob mRNA, and we show by quantitative PCR that more than one transcript cycles in fly heads. Using in situ hybridization, we observe differences in the expression patterns of the different transcripts. Immunohistochemistry on Drosophila heads reveals Slob71/65 protein to be enriched in the lateral neurons, in contrast to Slob57/51 protein, which is expressed most prominently in the pars intercerebralis neurons and dorsal giant interneurons. Using a heterologous expression system, we show that different Slobs bind to different extents to dSlo and 14-3-3. These data reveal an unexpected diversity of the dSlo/Slob/14-3-3 dynamic regulatory complex.

The amino terminus of Slob, Slowpoke channel binding protein, critically influences its modulation of the channel.

The Drosophila Slowpoke calcium-dependent potassium channel (dSlo) binding protein Slob was discovered by a yeast two-hybrid screen using the carboxy-terminal tail region of dSlo as bait. Slob binds to and modulates the dSlo channel. We have found that there are several Slob proteins, resulting from multiple translational start sites and alternative splicing, and have named them based on their molecular weights (in kD). The larger variants, which are initiated at the first translational start site and are called Slob71 and Slob65, shift the voltage dependence of dSlo activation, measured by the whole cell conductance-voltage relationship, to the left (less depolarized voltages). Slob53 and Slob47, initiated at the third translational start site, also shift the dSlo voltage dependence to the left. In contrast, Slob57 and Slob51, initiated at the second translational start site, shift the conductance-voltage relationship of dSlo substantially to more depolarized voltages, cause an apparent dSlo channel inactivation, and increase the deactivation rate of the channel. These results indicate that the amino-terminal region of Slob plays a critical role in its modulation of dSlo.