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Search Results: 1 - 10 of 595174 matches for " M.J; Cardona-Maya "
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?Existe asociación entre la morfología normal del espermatozoide y su cinética de desplazamiento?
Munuce,M.J; Cardona-Maya,W; Berta,CL;
Actas Urológicas Espa?olas , 2006, DOI: 10.4321/S0210-48062006000600006
Abstract: objective: to evaluate if there exist an association between the % of normal forms and the kinetic characteristics in human spermatozoa material and methods: a retrospective study was performed to analyze semen samples of 203 patients by computer assisted semen analysis. sperm morphology was evaluated by the aid of a micrometric objective according to strict criteria. only the patients presenting >20 x 106 sperm/ml and > 50% of progressive motility were included. data from 168 patients were divided according to the % of normal forms in three groups a) <4% (n=22), b) between 4-13% (n=89) and c) >14% (n=57). data collected among groups were compared. in order to select a motile sperm population 35 samples were treated by a discontinuous gradient and the % of normal forms as well as motility parameters evaluated before and after selection. results: the kinetic analysis showed that sperm concentration, the % of motile and rapid spermatozoa (>25 μm/s) as well as the average path velocity (vap) and the lateral head displacement (lhd) were increased in association with the % of normal spermatozoa presenting the lowest values in the group <4% with respect to the > 14% group, (p<0.05). linearity (lin) remained constant among groups. kinetic parameters and sperm morphology were significantly increased (p<0.0001) in the selected samples results showed that the use of gradients even in teratozoospermic samples improves significantly the % of normal forms respect to baseline values (p<0.0002). conclusions: our results would support the hypothesis that morphologically better spermatozoa would be associated with those with better movement parameters measured in an objective way. in this manner we could suggest that in vivo the best spermatozoa would comprise one "elite" in the journey through the fertilization site.
Nuevas opciones en anticoncepción: posible uso espermicida de plantas colombianas
álvarez-Gómez,A.M.a; Cardona-Maya,W.D.; Castro-álvarez,J.F.; Jiménez,Silvia; Cadavid,A.;
Actas Urológicas Espa?olas , 2007, DOI: 10.4321/S0210-48062007000400010
Abstract: currently there exists increasing preoccupation concerning sexual and reproductive health among teenagers; in spite of the availability of different contraceptive methods, the number of undesired pregnancies is steadily increasing. among the products presently available for birth control, spermicides are a means that can be totally controlled by the woman and are very reliable compared to other contraceptives in common use. however, they cause irritation in the vaginal epithelium due to their tensoactive effect on cellular membranes which might enhance the risk of acquiring sexually transmissible diseases. in searching for new alternatives, it was observed that a wide variety of plants have spermicidal activity. hence it is interesting to consider potential contraceptives of vegetable origin, as they may constitute a key tool to prevent undesired pregnancies in general, and in particular in vulnerable groups such as teenagers and young women.
Relación entre los polimorfismos de la metilen-tetrahidrofolato-reductasa y los niveles de homocisteína en mujeres con pérdida gestacional recurrente: perspectiva desde la nutrigenética
Cardona,H.; Cardona-Maya,W.; Gómez,J. G.; Casta?eda,S.; Gómez,J. M.; Bedoya,G.; álvarez,L.; Torres,J. D.; Tobón,L. I.; Cadavid,A.;
Nutrición Hospitalaria , 2008,
Abstract: the objective of this study was to evaluate if there is any difference in the proportion of methylenetetrahydrofolate reductase (mthfr) c677t polymorphisms and the homocysteine levels in a group of women with recurrent pregnancy loss (rpl) and a control group. ninety-three patients with diagnosis of three or more gestational losses and 206 healthy women with two or more children, were included. after acceptance of informed consent, samples of peripheral blood were taken to determine the genetic polymorphisms of mthfr c677t and the plasmatic levels of homocysteine. the carriers of the homozygous mutation tt of mthfr 677t polymorphism were 12.9% (12 of 93) in the group of patients and 14.6% (30 of 206) in the control group; 46.2% (43 of 93) and 40% (83 of 206) in the group of patients and controls respectively, were heterozygous ct for mthfr gene. the levels of homocysteine were 7.2 μmol/ml in the group of patients and 7.7 mmol/l in controls. there was no relationship between mthfr gene polymorphisms and the increase of homocysteine levels, nor of these one with rpl. from the nutrigenetics perspective we suggest that studies related to mthfr polymorphisms and the risk of disease include the levels of folate and b6 and b12 vitamins participating in the tetrahydrofolate cycle for trying to establish a direct relation among the genotype, the level of metabolite and the clinical manifestations. in this regard, we recommend the administration of folic acid in women in search of pregnancy due to the high frequency of heterozygous and homozygous for mthfr c677t mutation in our population.
Comparación de la concentración espermática usando la cámara de Makler y la cámara de Neubauer
Cardona-Maya,W.; Berdugo,J.; Cadavid,A.;
Actas Urológicas Espa?olas , 2008, DOI: 10.4321/S0210-48062008000400010
Abstract: objective: the aim of this work was to determine the concordance between the counts obtained with the makler and the neubauer chambers in ejaculates from fertile men. design: cross sectional study in reproduction group, university of antioquia, medellín-colombia. methods: 112 ejaculates from fertile men were analyzed in the present study. sperm count was determined using both chambers, the comparisons between chambers were determined using a bland-altman plot. results: the means values for sperm count were 107.8 and 106.2 x 106 sperm/ml using the makler and the neubauer chamber, respectively, and there was concordance between both methods. conclusion: our results show that the determination of sperm concentration with the makler chamber is as accurate as with the neubauer chamber and that either chamber can be used in routine semen analyses.
Relación entre los polimorfismos de la metilen-tetrahidrofolato-reductasa y los niveles de homocisteína en mujeres con pérdida gestacional recurrente: perspectiva desde la nutrigenética Relationship between methylenetetrahydrofolate reductase polymorphism and homocysteine levels in women with recurrent pregnancy loss: a nutrigenetic perspective
H. Cardona,W. Cardona-Maya,J. G. Gómez,S. Casta?eda
Nutrición Hospitalaria , 2008,
Abstract: El objetivo de este estudio fue evaluar si existe diferencia en la proporción de los polimorfismos de la metilen tetrahidrofolato reductasa (MTHFR) C677T y en los niveles de homocisteína, entre una población de mujeres con pérdida gestacional recurrente y un grupo control. Se incluyeron 93 pacientes con diagnóstico de tres o más pérdidas gestacionales y 206 mujeres sanas con dos o más hijos. Previa aceptación del consentimiento informado, a cada mujer se le tomó una muestra de sangre periférica tanto para la genotipificación de los polimorfismos de la MTHFR como para la medición de homocisteína en plasma. Las portadoras de la condición homocigota TT para el polimorfismo de la MTHFR 677T fueron 12,9% (12/93) en el grupo de pacientes y 14,6% (30/206) en el grupo control; un 46,2% (43/93) y 40% (83/206) en el grupo de pacientes y de controles respectivamente, fueron heterocigotos CT para el gen de la MTHFR. Los niveles promedio de homocisteína fueron 7,2 μmol/ml para las pacientes y 7,7 μmol/ml para los controles. No se encontró relación entre los polimorfismos del gen de la MTHFR y el aumento en los niveles de homocisteína, ni deéstos con la PGR. Desde la perspectiva de la nutrigenética, sugerimos que para estudiar la relación entre los polimorfismos de la MTHFR con determinada enfermedad, se tengan en cuenta los niveles de folatos, vitaminas B6 y B12 que intervienen en el ciclo de los tetrahidrofolatos con el fin de intentar establecer una relación más directa entre el genotipo, el nivel del metabolito y las manifestaciones clínicas. En este mismo sentido recomendamos el consumo de ácido fólico en las mujeres que estén buscando embarazo dado la alta frecuencia de heterocigotos y homocigotos para la mutación C677T de la MTHFR en nuestra población. The objective of this study was to evaluate if there is any difference in the proportion of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphisms and the homocysteine levels in a group of women with recurrent pregnancy loss (RPL) and a control group. Ninety-three patients with diagnosis of three or more gestational losses and 206 healthy women with two or more children, were included. After acceptance of informed consent, samples of peripheral blood were taken to determine the genetic polymorphisms of MTHFR C677T and the plasmatic levels of homocysteine. The carriers of the homozygous mutation TT of MTHFR 677T polymorphism were 12.9% (12 of 93) in the group of patients and 14.6% (30 of 206) in the control group; 46.2% (43 of 93) and 40% (83 of 206) in the group of patients and controls respectively, we
Virus de transmisión sexual: relación semen y virus
Zea-Mazo,J.W.; Negrette-Mejía,Y.A.; Cardona-Maya,W.;
Actas Urológicas Espa?olas , 2010, DOI: 10.4321/S0210-48062010001000006
Abstract: introduction: the possible "infection"/interaction processes between sperm and different microorganisms are being under discussion nowadays. this process might include some viruses and even recent investigations are aiming to elucidate the mechanisms and the receptors that may be involved in this interaction. furthermore, it has been reported the presence of some viral genomes within the sperm dna, raising the possibility of transmitting the infection to the partner and offspring. objective: the aim of this review is to describe the mechanisms by how viruses could possibly infect some seminal fractions. this is pursued by performing a literature review for answering the question: how the sexually transmitted virus could be infecting sperm? materials and methods: we carried out a bibliographic review about sperm and virus interaction. results: some viruses interact with sperm cells; and sperm cells could transfer the viruses to offspring, however, in most cases, the receptors that allow this interaction are not clearly described. conclusions: based on the current information, new in vitro studies are needed to determine the role of sperm in spreading viruses of sexually transmitted infections.
Comentarios sobre el artículo "Evaluación de las técnicas de capacitación espermática y su efecto en la fragmentación del ADN" Comments on "Assesment of sperm capacitation techniques and their effect on DNA fragmentation"
Wálter D Cardona-Maya
Revista Colombiana de Obstetricia y Ginecología , 2012,
Abstract:
Evaluación de la reacción acrosomal en espermatozoides humanos inducida por los monosacáridos manosa y N-acetilglucosamina
Cardona-Maya,W.D.; Cadavid,A.P.;
Actas Urológicas Espa?olas , 2005, DOI: 10.4321/S0210-48062005000700007
Abstract: objective: the aim of this investigation was to evaluate the role of the monosaccharides, mannose and n-acetylglucosamine in the induction of the acrosome reaction in human spermatozoa. methods: each individual gave a semen sample, the samples were capacitated using bovien serum albumin; the analysis of the mannose and n-acetylglucosamine induced acrosome reaction was evaluated for fluorescence microscopy and flow cytometry. results: the results obtained in the acrosomal reaction in the 10 samples evaluated by flow cytometry showed that only calcium ionophore a23187 induced acrosomal reaction (p<0.001); in contrast, by fluorescence microscopy, was observed a statistically significant increase in the induced acrosomal reaction with mannose and n-acetylglucosamine (p<0.001). conclusions: the monosaccharides mannose and n-acetylglucosamine induces partial acrosomal reaction and it does not complete, therefore the spermatozoa due to partial acrosomal reaction and the morphologics modifications that suffer during that process is able to fertilize the oocyte.
Parámetros seminales en hombre fértiles de dos poblaciones suramericanas
Berdugo,Jesús; Andrade-Rocha,Fernando; Cardona-Maya,Walter;
Archivos Espa?oles de Urología (Ed. impresa) , 2009, DOI: 10.4321/S0004-06142009000800006
Abstract: objectives: this retrospective study compared semen parameters from fertile men of two south american cities (medellín-colombia and petrópolis-brazil) to investigate their differences in some semen parameters. methods: we evaluated semen volume using a graduated tube, total progressive motility (a + b) using light microscopy (40x) and sperm concentration using a neubauer counting chamber. results: we observed that fertile men from medellín presented a significantly lower volume (p<0.0001), whereas individuals from petrópolis presented a significantly lower percentage of total progressive motility (p<0.0001). on the other hand, no difference was found in sperm concentration (p>0.05). conclusions: in conclusion, this study showed differences in semen parameters between fertile men of these south american populations. we think that these differences could be attributed to the geographical variations, like those observed in other countries. however, new studies are required to investigate this phenomenon and their causes.
Muerte embrionaria temprana: ?Tiene influencia el factor masculino?
Gil Villa,Aura María; Cardona-Maya,Wálter Darío; Cadavid Jaramillo,ángela Patricia;
Archivos Espa?oles de Urología (Ed. impresa) , 2007, DOI: 10.4321/S0004-06142007000900002
Abstract: 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.
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