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1.
Leuk Lymphoma ; 64(4): 816-821, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36695519

RESUMEN

Primary plasma cell leukemia (pPCL) is an infrequent and aggressive plasma cell disorder. The prognosis is still very poor, and the optimal treatment remains to be established. A retrospective, multicentric, international observational study was performed. Patients from 9 countries of Latin America (LATAM) with a diagnosis of pPCL between 2012 and 2020 were included. 72 patients were included. Treatment was based on thalidomide in 15%, proteasome inhibitors (PI)-based triplets in 38% and chemotherapy plus IMIDs and/or PI in 29%. The mortality rate at 3 months was 30%. The median overall survival (OS) was 18 months. In the multivariate analysis, frontline PI-based triplets, chemotherapy plus IMIDs and/or PI therapy, and maintenance were independent factors of better OS. In conclusion, the OS of pPCL is still poor in LATAM, with high early mortality. PI triplets, chemotherapy plus IMIDs, and/or PI and maintenance therapy were associated with improved survival.


Asunto(s)
Leucemia de Células Plasmáticas , Humanos , Leucemia de Células Plasmáticas/diagnóstico , Leucemia de Células Plasmáticas/epidemiología , Leucemia de Células Plasmáticas/terapia , Pronóstico , Bortezomib/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , América Latina/epidemiología , Agentes Inmunomoduladores , Demografía
2.
Poblac. salud mesoam ; 17(2)jun. 2020.
Artículo en Español | LILACS, SaludCR | ID: biblio-1386880

RESUMEN

Resumen Introducción: analizamos la prevalencia del parto vía cesárea en México para 2011-2014, buscando identificar algunos de los factores asociados a la presencia de cesárea durante el parto. Metodología: se realizó un análisis descriptivo y un modelo logístico multinivel con los registros de nacimientos del periodo 2011-2014, que incluye las características de la madre y del contexto. Resultados: se identificó que la presencia de factores relacionados con una mayor posibilidad de que el parto resulte en cesárea son mujeres que habitan municipios con población indígena, mayor escolaridad, mayor número de consultas prenatales, inicio temprano de estas y atenderse en clínicas privadas. También se identificó una mayor posibilidad de estancias prolongadas de hospitalización del parto si es por cesárea. Conclusiones: se observa un incremento en el número de cesáreas en hospitales públicos a partir del esquema de aseguramiento del Seguro Popular y se confirma la relación directa entre los múltiples factores analizados y la cesárea, entre ellos, mayor escolaridad, habitar en municipios predominantemente indígenas, así como en municipios con mayor índice de desarrollo humano.


Abstract Introduction: The objective is to analyze the prevalence of delivery by cesarean section in Mexico among 2011-2014, to identify some of the factors associated with its occurrence. Methods: A descriptive analysis and a multilevel logistic model was conducted among the data for Birth Information Subsystem, characteristics for the mother and context. Results: Identified that the factors associated with a greater likelihood that delivery result in cesarean section, are higher levels of education, greater number of prenatal visits, an early start to prenatal visits, giving birth in private health. Also a greater likelihood of prolonged hospitalization when delivery is by cesarean section. Conclusions: An increase in the number of caesarean sections in public hospitals is observed from the Popular Insurance assurance scheme; and the direct relationship between the multiple factors analyzed and the caesarean section is confirmed, including higher education, living in predominantly indigenous municipalities, as well as in municipalities with the highest human development index.


Asunto(s)
Humanos , Femenino , Factores Epidemiológicos , Cesárea/estadística & datos numéricos , México
3.
Int J Equity Health ; 19(1): 63, 2020 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-32381022

RESUMEN

The coronavirus disease 2019 (COVID-2019) pandemic struck Latin America in late February and is now beginning to spread across the rural indigenous communities in the region, home to 42 million people. Eighty percent of this highly marginalized population is concentrated in Bolivia, Guatemala, Mexico and Peru. Health care services for these ethnic groups face distinct challenges in view of their high levels of marginalization and cultural differences from the majority. Drawing on 30 years of work on the responses of health systems in the indigenous communities of Latin America, our group of researchers believes that countries in the region must be prepared to combat the epidemic in indigenous settings marked by deprivation and social disparity. We discuss four main challenges that need to be addressed by governments to guarantee the health and lives of those at the bottom of the social structure: the indigenous peoples in the region. More than an analysis, our work provides a practical guide for designing and implementing a response to COVID-19 in indigenous communities.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Coronavirus , Servicios de Salud del Indígena/organización & administración , Pandemias , Neumonía Viral/epidemiología , Grupos de Población , Población Rural , Betacoronavirus , COVID-19 , Etnicidad , Humanos , América Latina , SARS-CoV-2
4.
Asian J Androl ; 22(6): 623-628, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32217836

RESUMEN

Assisted reproductive technologies involving the use of spermatozoa and eggs for in vitro fertilization (IVF) have come as the solution for many infertile couples to become parents. However, in some cases, the use of ejaculated spermatozoa delivers poor IVF performance. Some studies have suggested the use of testicular spermatozoa in severe male infertility cases, but no guidelines regarding their utilization are currently available. In the present study, we found the mRNA protamine 1/protamine 2 (P1/P2) ratio to be a valuable biomarker of poor sperm function that could be used as a diagnostic key for the identification of cases that would benefit from the use of testicular spermatozoa. A total of 23 couples undergoing egg donation cycles with at least one previous cycle failure were studied. All couples underwent two consecutive intracytoplasmic sperm injection (ICSI) cycles with either ejaculated or testicular spermatozoa (TESA). The sperm mRNA P1/P2 ratio, fertilization rate, blastocyst rate, and pregnancy and live birth rate were compared. Results showed improved ICSI and clinical outcomes in cycles with testicular spermatozoa in men with altered mRNA P1/P2 ratios. TESA cycles presented significantly higher rates of fertilization (mean ± standard deviation: 76.1% ± 15.1% vs 65.5% ± 18.8%), blastocyst formation (55.0% ± 20.3% vs 30.8% ± 23.8%), and good morphological quality blastocyst (28.9% ± 22.9% vs 13.5% ± 17.9%) and also improvements on pregnancy (60.9% vs 0%) and healthy birth rates (56.5% vs 0%) than EJACULATE cycles. The results described here suggest that in patients with previous IVF/ICSI failures and aberrant mRNA protamine ratios, the use of testicular spermatozoa may be a good alternative to improve clinical outcomes.


Asunto(s)
Protaminas/metabolismo , ARN Mensajero/metabolismo , Técnicas Reproductivas Asistidas , Inyecciones de Esperma Intracitoplasmáticas , Recuperación de la Esperma , Espermatozoides/fisiología , Adulto , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
6.
Cryobiology ; 87: 117-119, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30707963

RESUMEN

PURPOSE: The purpose of this study is to present the first birth of healthy infant born following ICSI using the new permeable cryoprotectant-free sperm vitrification protocol Easy-Sperm®. PRINCIPAL RESULTS: A 39 years old woman and his 40 years old partner underwent egg donation treatment at IVF-Spain Alicante (Spain). Half of the mature oocytes obtained from a young and healthy donor were fertilized by ICSI, using slow-frozen spermatozoa and the other half with vitrified spermatozoa. A total of 5 blastocysts were obtained on day 5 (3 resulting from vitrified spermatozoa and 2 from frozen sperm). The best embryo, with AA quality (derived from one of the oocytes fertilized with vitrified sperm) was transferred. The woman conceived and, following a normal pregnancy, delivered a healthy boy. CONCLUSIONS: To the best of our knowledge, this is the first case report of a successful pregnancy and delivery of a healthy infant from ICSI with permeable vitrified spermatozoa in an oocyte donation program with transfer on blastocyst stage.


Asunto(s)
Criopreservación/métodos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Espermatozoides/trasplante , Vitrificación , Adulto , Orden de Nacimiento , Blastocisto/fisiología , Crioprotectores/análisis , Transferencia de Embrión , Femenino , Fertilización , Humanos , Masculino , Oocitos/fisiología , Embarazo , Espermatozoides/fisiología , Donantes de Tejidos
7.
Hum Genet ; 135(5): 555-568, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27068821

RESUMEN

MTHFR is an important enzyme in the metabolism of folic acid and is crucial for reproductive function. Variation in the sequence of MTHFR has been implicated in subfertility, but definitive data are lacking. In the present study, a detailed analysis of two common MTHFR polymorphisms (c.677C>T and c.1298A>C) was performed. Additionally, for the first time, the frequencies of different MTHFR alleles were assessed in preimplantation embryos. Several striking discoveries were made. Firstly, results demonstrated that maternal MTHFR c.1298A>C genotype strongly influences the likelihood of a pregnancy occurring, with the 1298C allele being significantly overrepresented amongst women who have undergone several unsuccessful assisted reproductive treatments. Secondly, parental MTHFR genotypes were shown to affect the production of aneuploid embryos, indicating that MTHFR is one of the few known human genes with the capacity to modulate rates of chromosome abnormality. Thirdly, an unusual deviation from Hardy-Weinberg equilibrium was noted for the c.677C>T polymorphism in subfertile patients, especially those who had experienced recurrent failure of embryo implantation or miscarriage, potentially explained by a rare case of heterozygote disadvantage. Finally, a dramatic impact of the MTHFR 677T allele on the capacity of chromosomally normal embryos to implant is described. Not only do these findings raise a series of interesting biological questions, but they also argue that testing of MTHFR could be of great clinical value, identifying patients at high risk of implantation failure and revealing the most viable embryos during in vitro fertilisation (IVF) cycles.


Asunto(s)
Aneuploidia , Desarrollo Embrionario/genética , Infertilidad/epidemiología , Infertilidad/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Estudios de Cohortes , Transferencia de Embrión , Femenino , Fertilización In Vitro , Humanos , Embarazo , Reino Unido/epidemiología
8.
Hum Genet ; 132(9): 1001-13, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23620267

RESUMEN

Despite the clinical importance of aneuploidy, surprisingly little is known concerning its impact during the earliest stages of human development. This study aimed to shed light on the genesis, progression, and survival of different types of chromosome anomaly from the fertilized oocyte through the final stage of preimplantation development (blastocyst). 2,204 oocytes and embryos were examined using comprehensive cytogenetic methodology. A diverse array of chromosome abnormalities was detected, including many forms never recorded later in development. Advancing female age was associated with dramatic increase in aneuploidy rate and complex chromosomal abnormalities. Anaphase lag and congression failure were found to be important malsegregation causing mechanisms in oogenesis and during the first few mitotic divisions. All abnormalities appeared to be tolerated until activation of the embryonic genome, after which some forms started to decline in frequency. However, many aneuploidies continued to have little impact, with affected embryos successfully reaching the blastocyst stage. Results from the direct analyses of female meiotic divisions and early embryonic stages suggest that chromosome errors present during preimplantation development have origins that are more varied than those seen in later pregnancy, raising the intriguing possibility that the source of aneuploidy might modulate impact on embryo viability. The results of this study also narrow the window of time for selection against aneuploid embryos, indicating that most survive until the blastocyst stage and, since they are not detected in clinical pregnancies, must be lost around the time of implantation or shortly thereafter.


Asunto(s)
Anafase/fisiología , Aneuploidia , Segregación Cromosómica/fisiología , Desarrollo Embrionario/genética , Desarrollo Embrionario/fisiología , Oogénesis/fisiología , Factores de Edad , Anafase/genética , Segregación Cromosómica/genética , Hibridación Genómica Comparativa , Análisis Citogenético , Femenino , Humanos , Oogénesis/genética , Embarazo
9.
Asian J Androl ; 13(5): 764-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21725332

RESUMEN

A wide variety of techniques for the preparation of sperm are currently available, of which the most commonly employed are density-gradient centrifugation (DGC) and swim-up (SUP). To date, these methods appear to be effective in selecting functional sperm for assisted reproduction techniques (ART), but they may have negative effects on sperm DNA. In this study, the ability of these semen processing techniques to eliminate spermatozoa containing single- and double-strand DNA damage was assessed by the two-tailed comet assay and the sperm chromatin dispersion test in 157 semen samples from patients seeking assisted reproduction treatment. Our results indicated that SUP and DGC are equally efficient in eliminating spermatozoa containing double-strand DNA damage and sperm with highly damaged (degraded) DNA, as characterized by the presence of both single- and double-strand DNA breaks. However, DGC is more efficient than SUP in selecting spermatozoa that are free from single-strand DNA damage. Future studies should characterise the importance of the various types of DNA damage and examine the sperm processing protocols used in each laboratory to determine their ability to eliminate DNA damage and hence, prevent the potential transmission of genetic mutations via ART.


Asunto(s)
Daño del ADN , Espermatozoides , Humanos , Masculino
10.
Reprod Fertil Dev ; 23(5): 633-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21635811

RESUMEN

Protamines of eutherian species are cysteine-rich molecules that become cross-linked by disulfide bonds during epididymal transit, whereas the protamines of most marsupial species lack cysteine residuals. The present study made use of the differences in protamine structure between eutherian and metatherian mammal spermatozoa to examine the comparative resistance of sperm DNA to oxidative damage in three eutherian species (Mus musculus, Homo sapiens, Sus domesticus) and three metatherian species (Vombatus ursinus, Phascolarctos cinereus, Macropus giganteus). Sperm DNA fragmentation of samples exposed to increasing concentrations of hydrogen peroxide was assessed by means of the two-tailed comet assay. The sperm DNA of the marsupial species studied were significantly more sensitive to oxidative stress than the spermatozoa of eutherian species. Such susceptibility is consistent with the lack of disulfide cross-linking in marsupial sperm chromatin and suggests that the oxidation of thiols to disulfides for chromatin condensation during epididymal transit in eutherian mammals is likely to be important in order to provide stability and protect these cells from the genotoxic effects of adverse environments.


Asunto(s)
Ensamble y Desensamble de Cromatina , Cromatina/metabolismo , Ensayo Cometa , Roturas del ADN de Cadena Simple , Estrés Oxidativo , Espermatozoides/metabolismo , Secuencia de Aminoácidos , Análisis de Varianza , Animales , Cromatina/química , Ensamble y Desensamble de Cromatina/efectos de los fármacos , Disulfuros/química , Disulfuros/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Peróxido de Hidrógeno/farmacología , Macropodidae , Masculino , Ratones , Datos de Secuencia Molecular , Oxidantes/farmacología , Estrés Oxidativo/efectos de los fármacos , Phascolarctidae , Protaminas/química , Protaminas/metabolismo , Especificidad de la Especie , Espermatozoides/efectos de los fármacos , Espermatozoides/patología , Sus scrofa
11.
Reprod Biomed Online ; 18(5): 609-16, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19549437

RESUMEN

DNA fragmentation is considered an important parameter of semen quality, and of significant value as a predictor of male fertility. Poor quality chromatin is closely associated with, and highly indicative of, some fertility problems. Many methodologies to assess DNA fragmentation in spermatozoa are available, but they are all unable to differentiate between single-stranded DNA breaks (SSB) and double-stranded DNA breaks (DSB) in the same sperm cell. The two-tailed Comet assay (2T-Comet) protocol overcomes this limitation. A modification of the original Comet assay was developed for the simultaneous evaluation of DNA SSB and DSB in human spermatozoa. The 2T-Comet assay is a fast, sensitive, and reliable procedure for the quantification and characterization of DNA damage in spermatozoa. It is an innovative method for assessing sperm DNA integrity, which has important implications for human fertility and andrological pathology.


Asunto(s)
Ensayo Cometa/métodos , Fragmentación del ADN , Espermatozoides/química , Naranja de Acridina , Humanos , Peróxido de Hidrógeno , Procesamiento de Imagen Asistido por Computador , Hibridación Fluorescente in Situ/métodos , Masculino , Sensibilidad y Especificidad , Estadísticas no Paramétricas
12.
Theriogenology ; 66(9): 2137-43, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16956655

RESUMEN

The semen quality of seven young adult boars was assessed for percentages of sperm motility, normal acrosomes, abnormal sperm, cells positive to sHOST (short Hipoosmotic Swelling Test), HPNA cells (sHOST Positive with Normal Acrosome cells) and the percentage of sperm heads, which exhibited DNA fragmentation using the Sperm Chromatin Dispersion test (SCD). These parameters were analysed in sperm samples both undiluted and diluted using a commercial extender and stored at 15 degrees C for 21 days. Results showed that semen quality decreases faster in the undiluted semen samples from day 0 to day 7 compared to diluted semen samples that remained with a high quality up to day 11. The undiluted semen exhibited a low DNA fragmentation index (DFI) during the first days and then a significant increase from day 7 up to day 21. This increase in the DFI coincided with the lowest levels of the other semen quality parameters. On the contrary, the samples diluted in the commercial extender showed very low levels of DNA fragmentation in all boars during the preservation period. When the evolution of DNA fragmentation was analysed in the undiluted samples, differences were found among boars. These differences were not shown in the samples diluted in the extender where the basal DFI remained stable during the 21 days. The main conclusion of this study was that some sperm extenders delay or partially prevent sperm DNA fragmentation.


Asunto(s)
Fragmentación del ADN/efectos de los fármacos , Preservación de Semen/veterinaria , Espermatozoides/efectos de los fármacos , Porcinos/fisiología , Acrosoma/fisiología , Animales , Frío , Daño del ADN , Yema de Huevo , Masculino , Preservación de Semen/métodos , Recuento de Espermatozoides/veterinaria , Motilidad Espermática/fisiología , Espermatozoides/anomalías , Espermatozoides/fisiología , Factores de Tiempo
13.
J Androl ; 27(1): 106-11, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16400086

RESUMEN

The frequency of sperm cells with fragmented DNA was studied in a group of 18 infertile patients with varicocele and compared with those obtained in a group of 51 normozoospermic patients, 103 patients with abnormal standard semen parameters, and 22 fertile men. The spermatozoa were processed to discriminate different levels of DNA fragmentation using the Halosperm kit, an improved Sperm Chromatin Dispersion (SCD) test. In this technique, after an acid incubation and subsequent lysis, those sperm cells without DNA fragmentation show big or medium-sized halos of dispersion of DNA loops from the central nuclear core. Otherwise, those spermatozoa containing fragmented DNA either show a small halo, exhibit no halo with solid staining of the core, or show no halo and irregular or faint stain of the remaining core. The latter, that is, degraded type, corresponds to a much higher level of DNA-nuclear damage. The varicocele patients showed 32.4% +/- 22.3% of spermatozoa with fragmented DNA, significantly different from the group of fertile subjects (12.6% +/- 5.0%). Nevertheless, this was not different from that of normozoospermic patients (31.3% +/- 16.6%) (P = .83) and with abnormal semen parameters (36.6% +/- 15.5%) (P = .31). No significant differences were found between the normozoospermic patients and the patients with abnormal semen parameters. Strikingly, the proportion of the degraded cells in the total of sperm cells with fragmented DNA was 1 out of 4.2 (23.9% +/- 12.9%) in the case of varicocele patients, whereas it was 1 out of 8.2 to 9.7 in the normozoospermic patients (11.1% +/- 9.9%) in the patients with abnormal sperm parameters (12.2% +/- 8.3%) and in the fertile group (10.3% +/- 7.2%). Thus, whereas no differences in the percentage of sperm cells with fragmented DNA were evident with respect to other infertile patients, individuals with varicocele exhibit a higher yield of sperm cells with the greatest nuclear DNA damage level in the population with fragmented DNA. This finding illustrates the value of assessing different patterns of DNA-nuclear damage within each sperm cell and the particular ability of the Halosperm kit to reveal them.


Asunto(s)
Núcleo Celular/metabolismo , Cromatina/metabolismo , Infertilidad Masculina/patología , Recuento de Espermatozoides , Espermatozoides/ultraestructura , Varicocele/patología , Adolescente , Adulto , Fragmentación del ADN , Humanos , Etiquetado Corte-Fin in Situ , Masculino
14.
Theriogenology ; 65(2): 308-16, 2006 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-15996725

RESUMEN

We present a new, rapid and simple method to study DNA Fragmentation Index (DFI) in sperm samples from boar under bright-field and fluorescence microscopy. Discrimination of sperm cells containing fragmented DNA relies on the extreme peripheral diffusion of their chromatin fragments, whereas those sperm nuclei without DNA fragmentation do not disperse or show very restricted spreading of DNA loops close to the flagellum. The basic methodology provided in the commercial kit Sperm-Sus-Halomax allows, in addition to a direct estimation of DFI in a sperm sample under bright field microscopy, a direct visualization of DNA breaks by incorporation of labelled nucleotides using the DNA polymerase I following the in situ nick translation assay (ISNT methodology not provided in the kit). An external control using DBD-FISH (DNA breakage detection-fluorescence in situ hybridization) on human and boar sperm samples was used in this experiment. The results obtained show (i) low levels of background DNA fragmentation (from 0.7 to 10%), (ii) no significant differences for DFI after the application of Sperm-Sus-Halomax and ISNT, with a tendency to be underestimated after using DBD-FISH and (iii) a characteristic chromatin organization in boar sperm nucleus, with a particular response to chromatin loop relaxation and preferential DNA labelling by ISNT at the proximal nuclear area, close to the flagellum. This methodology allows the routine assessment of boar sperm samples for DFI, as well as basic and clinical research on this relevant topic in any laboratory of semen analysis.


Asunto(s)
Fragmentación del ADN , Microscopía/veterinaria , Espermatozoides/citología , Porcinos/fisiología , Animales , Núcleo Celular/genética , Humanos , Hibridación Fluorescente in Situ/métodos , Hibridación Fluorescente in Situ/veterinaria , Masculino , Microscopía/métodos , Microscopía Fluorescente/métodos , Microscopía Fluorescente/veterinaria , Espermatozoides/fisiología
15.
Fertil Steril ; 84(4): 833-42, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16213830

RESUMEN

OBJECTIVE: To improve the sperm chromatin dispersion (SCD) test and develop it as a simple kit (Halosperm kit) for the accurate determination of sperm DNA fragmentation using conventional bright-field microscopy. DESIGN: Method development, comparison, and validation. SETTING: Medical genetics laboratory, academic biology center, and reproductive medicine centers. PATIENT(S): Male infertility patients attending the Reproductive Medicine Center. A varicocele patient and a group of nine fertile subjects. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): [1] The quality of chromatin staining in relaxed sperm nuclear halos and tail preservation; [2] SCD scoring reproducibility; [3] comparison with the sperm chromatin structure assay in 45 samples; [4] frequency of sperm with DNA fragmentation after incubation with increasing doses of the nitric oxide donor sodium nitroprusside and in sperm samples for 9 fertile men, 46 normozoospermic patients, 23 oligoasthenoteratozoospermic patients, and a subject with varicocele. RESULT(S): The sperm nuclei with DNA fragmentation, either spontaneous or induced, do not produce or show very small halos of DNA loop dispersion after sequential incubation in acid and lysis solution. The improved SCD protocol (Halosperm kit) results in better chromatin preservation, therefore highly contrasted halo images can be accurately assessed using conventional bright-field microscopy after Wright staining. Moreover, unlike in the original SCD procedure, the sperm tails are now preserved, making it possible to unequivocally discriminate sperm from other cell types. The chi2 test did not detect significant differences in the mean number of sperm cells with fragmented DNA as scored by four different observers. The intraobserver coefficient of variation for the estimated percentage of spermatozoa with fragmented DNA ranged from 6% to 12%. There was good correlation between the SCD and the sperm chromatin structure assay DNA fragmentation index (intraclass correlation coefficient R: 0.85; percent DNA fragmentation index mean difference: 2.16 significantly higher for SCD). Using the Halosperm kit, a dose-dependent increase in sperm DNA damage after sodium nitroprusside incubation was detected. The percentage of sperm cells with fragmented DNA in the fertile group was 16.3 +/- 6.0, in the normozoospermic group, 27.3 +/- 11.7, and in the oligoasthenoteratozoospermic group, 47.3 +/- 17.3. In the varicocele sample, an extremely high degree of nuclear disruption was detected in the population of sperm cells with fragmented DNA. CONCLUSION(S): The improved SCD test, developed as the Halosperm kit, is a simple, cost effective, rapid, reliable, and accurate procedure, for routinely assessing human sperm DNA fragmentation in the clinical andrology laboratory.


Asunto(s)
Cromatina/patología , Fragmentación del ADN , Técnicas Genéticas , Espermatozoides/patología , Cromatina/química , Fragmentación del ADN/genética , Humanos , Masculino , Recuento de Espermatozoides/métodos , Espermatozoides/química , Estadísticas no Paramétricas
17.
Bogotá, D.C; s.n; 1989. 195 p. tab, graf.
Tesis en Español | LILACS | ID: lil-189947

RESUMEN

Con el fín de contribuir al desarrollo de los materiales restaurativos para dientes posteriores se realizó un estudio de resinas compuestas, de carácter descriptivo, a partir de una muestra de pacientes que asistian a colsulta odontológica particular. Los resultados obtuvieron de los hallazgos clínicos observados durante los controles realizados en el transcurso del estudio. Las variables estudiadas fueron: Adaptación Marginal, Forma Anatómica, Incidencia de Caries Recurrente, Pigmentación del Margen y Estabilidad del Color. El estudio desmostró que las variables de pigmentación marginal y forma anatómica no obtuvieron resultados tan satisfactorios como la adaptación marginal, la incidencia de caries recurrente y la estabilidad del color. Sin embargo, la estabilidad del color fué la unica variable que presentó el cargo más drástico sin que esto demedite el comportamiento clínico y por tanto no sugiere el campo de la restauración. Los resultados obtenidos en este estudio contribuyen a una mayor acertación de las resinas compuestas para dientes posteriores


Asunto(s)
Resinas Compuestas
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