Aspectos biológicos del Aedes Aegypti y manifestaciones clínicas del dengue / Biological aspects of the Aedes Aegypti and clinical manifestations of Dengue

El dengue en la actualidad constituye un grave problema de salud para Cuba y para otros países de áreas tropicales donde se encuentran las condiciones propicias para la aparición de brotes epidémicos de la enfermedad que causan grandes daños a la salud y a la economía. Es por ello que se realiza este trabajo donde se actualiza el tema en lo concerniente a la situación mundial y en el área de las Américas, profundizándose en el ciclo biológico del vector y en el cuadro clínico, siendo el objetivo del trabajo elevar el conocimiento sobre esta enfermedad para fortalecer su control contribuyendo de esta manera a la disminución de su incidencia en cuanto a morbilidad y mortalidad en la población cubana. Se efectuó una amplia revisión bibliográfica donde se tomaron 20 referencias, haciendo énfasis en tesis doctorales de científicos del Instituto de Medicina Tropical Pedro Kourí(AU)

At the present times Dengue represents a serious health problem for Cuba and for other countries located in tropical areas where favorable conditions for epidemic outbreaks can provoke enormous damages to health and the economy. This research paper updates the worldwide situation as well as in the area of Las Americas deepening in the cycle of life of the vector and in the clinical manifestations of the disease. The main purpose of this research is to raise knowledge about the disease in order to strengthen its control to diminish its incidence, morbidity and mortality rates in the Cuban population. A full medical literature review about the topic was completed, emphasizing on the thesis for the academic degree of Ph.D. of scientists from the Pedro Kourí Institute of Tropical Medicine(AU)

Cyclic nucleotide phosphodiesterase inhibition increases tyrosine phosphorylation and hyper motility in normal and pathological human spermatozoa

Our objective was to determine the effect of phosphodiesterase (PDE) inhibition on: 1) tyrosine phosphorylation of human spermatozoa at the tail level; and 2) sperm motion parameters and hyperactivated motility. The study was conducted with normozoospermic and asthenozoospermic samples incubated under in vitro capacitating conditions. The main outcome measures were computer-assisted sperm motion analysis and fluorescent immunodetection of phosphotyrosine-containing proteins. Pentoxifylline (PTX) was used as PDE inhibitor because of its wide use in the clinic. PTX-treatment significantly increased sperm velocity, hyperactivated motility and tyrosine-phosphorylation, both in normo and asthenozoospermic samples. Tyrosine-phosphorylation of tail proteins was highly conspicuous in both types of samples, showing no differential pattern after PTX-treatment. Normozoospermic samples treated with pentoxifylline showed an increase in the number of spermatozoa displaying hyperactivated movement and tyrosine-phosphorylation at the tail level. Preliminary data on asthenozoospermic samples exhibiting altered motion characteristics and defective phosphorylation of sperm-tail proteins showed that both defects can be concomitantly overcome by pentoxifylline treatment. Tyrosine-phosphorylation of sperm-tail proteins is underlying the enhancement of hyperactivated motility resulting from PDE inhibition by pentoxifylline.

Cyclic nucleotide phosphodiesterase inhibition increases tyrosine phosphorylation and hyper motility in normal and pathological human spermatozoa.

Our objective was to determine the effect of phosphodiesterase (PDE) inhibition on: 1) tyrosine phosphorylation of human spermatozoa at the tail level; and 2) sperm motion parameters and hyperactivated motility. The study was conducted with normozoospermic and asthenozoospermic samples incubated under in vitro capacitating conditions. The main outcome measures were computer-assisted sperm motion analysis and fluorescent immunodetection of phosphotyrosine-containing proteins. Pentoxifylline (PTX) was used as PDE inhibitor because of its wide use in the clinic. PTX-treatment significantly increased sperm velocity, hyperactivated motility and tyrosine-phosphorylation, both in normo and asthenozoospermic samples. Tyrosine-phosphorylation of tail proteins was highly conspicuous in both types of samples, showing no differential pattern after PTX-treatment. Normozoospermic samples treated with pentoxifylline showed an increase in the number of spermatozoa displaying hyperactivated movement and tyrosine-phosphorylation at the tail level. Preliminary data on asthenozoospermic samples exhibiting altered motion characteristics and defective phosphorylation of sperm-tail proteins showed that both defects can be concomitantly overcome by pentoxifylline treatment. Tyrosine-phosphorylation of sperm-tail proteins is underlying the enhancement of hyperactivated motility resulting from PDE inhibition by pentoxifylline.

Cyclic nucleotide phosphodiesterase inhibition increases tyrosine phosphorylation and hyper motility in normal and pathological human spermatozoa.

Our objective was to determine the effect of phosphodiesterase (PDE) inhibition on: 1) tyrosine phosphorylation of human spermatozoa at the tail level; and 2) sperm motion parameters and hyperactivated motility. The study was conducted with normozoospermic and asthenozoospermic samples incubated under in vitro capacitating conditions. The main outcome measures were computer-assisted sperm motion analysis and fluorescent immunodetection of phosphotyrosine-containing proteins. Pentoxifylline (PTX) was used as PDE inhibitor because of its wide use in the clinic. PTX-treatment significantly increased sperm velocity, hyperactivated motility and tyrosine-phosphorylation, both in normo and asthenozoospermic samples. Tyrosine-phosphorylation of tail proteins was highly conspicuous in both types of samples, showing no differential pattern after PTX-treatment. Normozoospermic samples treated with pentoxifylline showed an increase in the number of spermatozoa displaying hyperactivated movement and tyrosine-phosphorylation at the tail level. Preliminary data on asthenozoospermic samples exhibiting altered motion characteristics and defective phosphorylation of sperm-tail proteins showed that both defects can be concomitantly overcome by pentoxifylline treatment. Tyrosine-phosphorylation of sperm-tail proteins is underlying the enhancement of hyperactivated motility resulting from PDE inhibition by pentoxifylline.

Incidence of sperm-tail tyrosine phosphorylation and hyperactivated motility in normozoospermic and asthenozoospermic human sperm samples.

Our objective was to study the incidence of sperm-tail phosphotyrosine immunoreactivity in normozoospermic and asthenozoospermic human sperm samples, its association with sperm motion parameters, particularly hyperactivated motility, and its potential involvement in the pathogenesis of asthenozoospermia. The work was conducted as a prospective experimental study in the Sperm Biology and Andrology laboratories of the Jones Institute, a medical school-based fertility center. The study subjects were healthy fertile male donors (normozoospermic samples) and infertile patients (asthenozoospermic samples) attending the center. Recently ejaculated semen samples were washed twice to eliminate seminal plasma and a swim-up was performed to select the motile population which, in turn, was incubated up to 18 h at 37 degrees C in 3.5% human serum albumin-supplemented Ham's F10 to allow for capacitation. For evaluation, sperm aliquots were taken pre-swim-up (T0), immediately post swim-up (T1), at 6 h (T6), and 18 h (T18) of incubation. The main outcome measures were computer-analyzed sperm motion parameters and hyperactivated motility, and immunodetection of phosphotyrosine (PY)-containing proteins. During the capacitating incubation, normozoospermic samples displayed maximum motility, velocity, and hyperactivation at T6, significantly decreasing their values at T18. PY-proteins were located both at the tail and head of spermatozoa. Their expression increased progressively during the incubation, being present in about 70% of the sperm tails at T18. Asthenozoospermic samples showed an inability to respond to capacitation with an increase in motion parameters and PY-phosphorylation. At T6, both hyperactivation and PY-phosphorylation were significantly lower than in normal samples. Our results suggest that PY-phosphorylation of tail proteins is highly conspicuous in human spermatozoa, and increases its incidence in a time-dependent manner, as more sperm become capacitated. Asthenozoospermic samples displaying low percentages of motile sperm and altered motion characteristics showed a decreased incidence of PY-phosphorelated sperm. Tail protein PY-phosphorylation may be related to sperm movement, especially to hyperactivated motility and its deficiency may be associated to asthenozoospermia.

Incidence of sperm-tail tyrosine phosphorylation and hyperactivated motility in normozoospermic and asthenozoospermic human sperm samples.

Our objective was to study the incidence of sperm-tail phosphotyrosine immunoreactivity in normozoospermic and asthenozoospermic human sperm samples, its association with sperm motion parameters, particularly hyperactivated motility, and its potential involvement in the pathogenesis of asthenozoospermia. The work was conducted as a prospective experimental study in the Sperm Biology and Andrology laboratories of the Jones Institute, a medical school-based fertility center. The study subjects were healthy fertile male donors (normozoospermic samples) and infertile patients (asthenozoospermic samples) attending the center. Recently ejaculated semen samples were washed twice to eliminate seminal plasma and a swim-up was performed to select the motile population which, in turn, was incubated up to 18 h at 37 degrees C in 3.5

human serum albumin-supplemented Hams F10 to allow for capacitation. For evaluation, sperm aliquots were taken pre-swim-up (T0), immediately post swim-up (T1), at 6 h (T6), and 18 h (T18) of incubation. The main outcome measures were computer-analyzed sperm motion parameters and hyperactivated motility, and immunodetection of phosphotyrosine (PY)-containing proteins. During the capacitating incubation, normozoospermic samples displayed maximum motility, velocity, and hyperactivation at T6, significantly decreasing their values at T18. PY-proteins were located both at the tail and head of spermatozoa. Their expression increased progressively during the incubation, being present in about 70

of the sperm tails at T18. Asthenozoospermic samples showed an inability to respond to capacitation with an increase in motion parameters and PY-phosphorylation. At T6, both hyperactivation and PY-phosphorylation were significantly lower than in normal samples. Our results suggest that PY-phosphorylation of tail proteins is highly conspicuous in human spermatozoa, and increases its incidence in a time-dependent manner, as more sperm become capacitated. Asthenozoospermic samples displaying low percentages of motile sperm and altered motion characteristics showed a decreased incidence of PY-phosphorelated sperm. Tail protein PY-phosphorylation may be related to sperm movement, especially to hyperactivated motility and its deficiency may be associated to asthenozoospermia.

The role of LHRH agonists and antagonists.

Administration of GnRH analogues (agonists as well as antagonists) produces suppression of the pituitary---gonadal axis, thus inhibiting the secretion of LH, FSH and sexual steroids. For this reason, analogs are indicated in all those clinical situations where suppression of gonadotrophins (precocious puberty, contraception) or of sexual steroids (endometriosis, prostate hyperplasia, cancer, uterine fibroids) is desired. For several years GnRH agonists have been used in combination with gonadotrophins for ovarian stimulation for assisted reproduction in order to control premature LH surges and to reduce cancellation rate with improvement of the pregnancy rate per cycle. This effect is obtained after 2 weeks of agonist administration. The immediate suppression of the pituitary achieved by GnRH antagonists without an initial stimulatory effect is the main advantage of these compounds over the agonists. The prevention of a premature LH surge by GnRH antagonists can be obtained by multiple dose or by a single administration. Both protocols offer the following advantages over the agonists: they require fewer ampoules of gonadotrophins, shorter duration of stimulation, there is a preserved pituitary response to GnRH, less risk of ovarian hyperstimulation syndrome and the luteal phase seems to be more preserved. The main disadvantages of the antagonists are that they are expensive and that pregnancy rate appears to be slightly lower than with the agonists. GnRH antagonists will probably replace agonists in ovarian stimulation treatment for assisted reproduction techniques.

Alteración de mecanismos moleculares y activación abortiva en oocitos humanos durante las fallas de fecundación: aspectos biológicos / Alteration of molecular mechanisms and abortive activation in human oocytes during the failures of fertilization

Introducción: Los primeros estudios relacionados con falla de fecundación en humanos se concentraron en la citogenética del oocito. Más recientemente, los avances en imágenes digitales y microscopía de fluorescencia han permitidos investigar eventos menos conocidos como la movilidad citoplásmica de los pronúcleos masculino y femenino y los mecanismos físicos que dirigen su unión. Objetivo: Analizar cualitativa y cuantitativamente oocitos no fecundados luego de FIV e ICSI, haciendo hincapié en la organización del citoesqueleto, estado de la cromatina, organización del áster y presencia de activaciones abortivas. Materiales y Métodos: Se estudiaron 248 oocitos clasificados como "no fecundados" luego de fertilización in vitro (FIV) e inyección intracitoplásmica de espermatozoides (ICSI) 20-40 hs post inseminación o inyección. El material se procesó para inmunofluorescencia mediante la utilización de anticuerpos monoclonales para la detección de O y ß tubulinas y O tubulinas acetiladas. El material genético se estudió por tinción con Hoechst 33258 y se analizó por microscopía óptica (UV). El análisis citogenético se realizó en 69 oocitos activados luego de ICSI de acuerdo a la técnica de Tarkowski (1966). Los resultados se analizaron estadísticamente mediante el test de Chi cuadrado. Resultados y Discusión: Inmunofluorescencia: 1) FIV: La principal causa de falla de fecundación luego de FIV fue la ausencia de penetración espermática (54,9 por ciento). De los restantes oocitos estudiados, el 11,4 por ciento mostraron una falla de activación oocitaria y el 23,9 por ciento presentaron fallas en los procesos de nucleación o migración de pronúcleos. 2) ICSI: La principal causa de falla de fecundación luego de ICSI resultó ser la falla de activación oocitaria (36,5 por ciento). Un 14,6 por ciento de los oocitos remanentes detuvieron su desarrollo en la primera placa metafásica. En general, las fallas detectadas luego de FIV ó ICSI resultaron cuantitativamente diferentes. Análisis cromosómico en oocitos activados post ICSI: El estudio cromosómico permitió identificar la presencia de activaciones abortivas, incluyendo metafases III (MIII), núcleos reticulares (NR) y núcleos telofásicos (NT) (AU)

Alteración de mecanismos moleculares y activación abortiva en oocitos humanos durante las fallas de fecundación: aspectos biológicos / Alteration of molecular mechanisms and abortive activation in human oocytes during the failures of fertilization

Introducción: Los primeros estudios relacionados con falla de fecundación en humanos se concentraron en la citogenética del oocito. Más recientemente, los avances en imágenes digitales y microscopía de fluorescencia han permitidos investigar eventos menos conocidos como la movilidad citoplásmica de los pronúcleos masculino y femenino y los mecanismos físicos que dirigen su unión. Objetivo: Analizar cualitativa y cuantitativamente oocitos no fecundados luego de FIV e ICSI, haciendo hincapié en la organización del citoesqueleto, estado de la cromatina, organización del áster y presencia de activaciones abortivas. Materiales y Métodos: Se estudiaron 248 oocitos clasificados como "no fecundados" luego de fertilización in vitro (FIV) e inyección intracitoplásmica de espermatozoides (ICSI) 20-40 hs post inseminación o inyección. El material se procesó para inmunofluorescencia mediante la utilización de anticuerpos monoclonales para la detección de Ó y ß tubulinas y Ó tubulinas acetiladas. El material genético se estudió por tinción con Hoechst 33258 y se analizó por microscopía óptica (UV). El análisis citogenético se realizó en 69 oocitos activados luego de ICSI de acuerdo a la técnica de Tarkowski (1966). Los resultados se analizaron estadísticamente mediante el test de Chi cuadrado. Resultados y Discusión: Inmunofluorescencia: 1) FIV: La principal causa de falla de fecundación luego de FIV fue la ausencia de penetración espermática (54,9 por ciento). De los restantes oocitos estudiados, el 11,4 por ciento mostraron una falla de activación oocitaria y el 23,9 por ciento presentaron fallas en los procesos de nucleación o migración de pronúcleos. 2) ICSI: La principal causa de falla de fecundación luego de ICSI resultó ser la falla de activación oocitaria (36,5 por ciento). Un 14,6 por ciento de los oocitos remanentes detuvieron su desarrollo en la primera placa metafásica. En general, las fallas detectadas luego de FIV ó ICSI resultaron cuantitativamente diferentes. Análisis cromosómico en oocitos activados post ICSI: El estudio cromosómico permitió identificar la presencia de activaciones abortivas, incluyendo metafases III (MIII), núcleos reticulares (NR) y núcleos telofásicos (NT)

El factor masculino. III. Importancia, diagnóstico y perspectivas / The masculine factor. III. Importancia, diagnosis and perspectives

De acuerdo con la Organización Mundial de la Salud el factor masculino está presente en el 40-50 por ciento de las parejas infértiles, de aquí la importancia en la continuidad de los estudios multidisciplinarios relacionados con los mecanismos que regulan el fenómeno reproductivo en el hombre. El análisis completo del semen o espermatobioscopia, continúa siendo prácticamente el único instrumento para el estudio del varón con trastornos en su fertilidad. Sin embargo, el principal problema para establecer un diagnóstico confiable con valor predictivo de infertilidad masculina, radica en que aún están en proceso de validación el conjunto de características morfológicas y/o funcionales del gameto masculino que determinan su habilidad fertilizante. Aún más, tampoco se ha establecido con precisión la correlación entre las características del semen y las concentraciones hormonales, bioactivas presentes en sangre periférica, con el potencial de fertilidad de un individuo. En este contexto se presentan los aspectos que se consideran más importantes en relación con la fertilidad masculina, entre otros: las principales causas de la infertilidad, el avance en el establecimiento de la correlación morfofuncional que determina la habilidad fertilizante del gameto masculino y los criterios que deben prevalecer en el laboratorio para el manejo y evaluación correcta de las muestras de semen