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Sperm maturation and capacitation in the open thelycum shrimp Litopenaeus (Crustacea: Decapoda: Penaeoidea)
(Aquaculture, 2007-07-28) Alfaro Montoya, Jorge; Ulate Naranjo, Karol; Vargas Montero, Maribelle
Transmission electron microscopy was applied to sperm removed from males and females belonging to Litopenaeus vannamei, L. stylirostris and L. occidentalis. It was discovered that a region named filamentous meshwork (FM), located between the nucleus and the hemispherical cap, develops differently in these three closely related species. In L. vannamei, the FM is synthesized in the male reproductive system, but seems to complete its formation after mating. In L. stylirostris, the FM region was not present in spermatophores collected from males or in sperm from the thelycum. In L. occidentalis, the FM region is fully developed in male sperm. It is suggested that completion of the FM is required for acrosome maturation, and the process continues after mating in some species of Litopenaeus. In vitro induction of the acrosome reaction in sperm from males and females of L. occidentalis demonstrated for the first time that reactivity is significantly superior in sperm cells that have been attached to the open thelycum for some hours, as compared to sperm in males (prior to transfer). This finding suggests that matured sperm cells of L. occidentalis become capacitated to react against egg water after mating. © 2007 Elsevier B.V. All rights reserved.
Evaluation of systemic and mucosal anti-HPV16 and anti-HPV18 antibody responses from vaccinated women
(Vaccine, 2008-07-04) Kemp, Troy J.; García Piñeres, Alfonso Javier; Falk, Roni T.; Poncelet, Sylviane; Dessy, Francis; Giannini, Sandra L.; Rodríguez, Ana Cecilia; Porras Martínez, Carolina; Herrero, Rolando; Hildesheim, Allan; Pinto, Ligia A.
Ideal methods to monitor HPV neutralizing antibodies induced by vaccination have not been established yet. Here, we evaluated systemic and cervical antibody levels induced by HPV16/18 AS04-adjuvanted vaccine (GlaxoSmithKline Biologicals) using a secreted alkaline phosphatase neutralization assay (SEAPNA) and enzyme-linked immunosorbent assay (ELISA). Serum and cervical secretions from 50 vaccinated women were used to assess (1) overall assay reproducibility; (2) inter-assay and inter-specimen correlation; (3) correlations between month 1 and month 12 titers. Strong correlations between SEAP-NA and ELISA were observed (serum anti-HPV16/18, = 0.91/0.85; cervix anti-HPV16/18, = 0.84/0.89). Systemic and cervical antibody measures also correlated well (range: 0.64–0.75); except at mid-cycle (range: 0.28–0.65). Correlations between antibody levels at 1 and 12 months following the start of vaccination were poor (range: 0.16–0.38). In conclusion, HPV16/18 VLP-based ELISA is a reliable and valid method to monitor anti-HPV16/18 neutralizing potential for the first year following vaccination; however, additional studies will be required to better define the effects of the time on cycle and patterns of antibody response over time following vaccination. © 2008 Elsevier Ltd. All rights reserved.
Epidemiology of Genital Chlamydia trachomatis Infection Among Young Women in Costa Rica
(Sexually Transmitted Diseases, 2008-05) Porras Martínez, Carolina; Safaeian, Mahboohbeh; González, Paula; Hildesheim, Allan; Silva, Sandra; Schiffman, Mark; Rodríguez, Ana Cecilia; Wacholder, Sholom; Freer, Enrique; Quint, Koen; Bratti, Concepción; Espinoza, Albert; Cortes, Bernal; Herrero, Rolando
El estudio analiza la epidemiología de la infección genital por Chlamydia trachomatis (Ct) en mujeres jóvenes de Costa Rica, específicamente en Guanacaste y Puntarenas. Con una muestra de 5829 mujeres entre 18 y 25 años, se encontró una prevalencia de Ct del 14.2%, una de las más altas reportadas a nivel mundial. Los factores de riesgo más significativos fueron el número de parejas sexuales, el estado civil, el uso actual de dispositivos intrauterinos (DIU), el tabaquismo y la presencia de ectopia cervical. También se observó una fuerte correlación entre Ct y otras infecciones de transmisión sexual como gonorrea y VPH. El estudio recomienda implementar programas de tamizaje y educación sobre el uso correcto del condón, además de investigar más a fondo el papel de los DIU y las coinfecciones en contextos de alta prevalencia.
Studies on the venom proteome of Bothrops asper: Perspectives and applications
(Toxicon, 2009-12-01) Alape Girón, Alberto; Flores Díaz, Marietta; Sanz, Libia; Madrigal Villalobos, Marvin; Escolano, José; Sasa Marín, Mahmood; Calvete Chornet, Juan José
Bothrops asper is responsible for the vast majority of snakebite accidents in Central America and several studies have demonstrated that specific toxic and enzymatic activities of its venom vary with the geographic origin and age of the specimens. Variability in venom proteins and enzymes between specimens from the Caribbean and the Pacific versants of Costa Rica has been reported since 1964. Recently, we performed a comparative proteomic characterization of the venoms from one population of each versant. Proteins belonging to several families, including disintegrin, phospholipases A2, serine proteinases, C-type lectins, CRISP, L-amino acid oxidase, and Zn2þ-dependent metalloproteinases show a variable degree of relative occurrence in the venoms of both populations. The occurrence of prominent differences in the protein profile between venoms from adults and newborns, and among venom samples from individual specimens of the same region or developmental stage, further demonstrated the existence of geographic, ontogenetic and individual variability in the venom proteome of this species. These findings provide new insights towards understanding the biology of B. asper, contribute to a deeper understanding of the pathology induced by its venom and underscore the importance of the use of venoms pooled from specimens from both regions for producing antivenom exhibiting the broadest cross-reactivity. Furthermore, knowledge of the protein composition of B. asper venom paves the way for detailed future structure–function studies of individual toxins as well as for the development of new protocols to study the reactivity of therapeutic antivenoms.
Empiema postraumático: factores relacionados y experiencia en Hospital San Juan de Dios entre 2022-2023
(2025) Herrera Rosales, María Paula; Bolaños Cubillo, Albert Jesús
El empiema postraumático, se entiende como la sobreinfección del espacio pleural posterior al trauma torácico. Esta es una condición de etiología multifactorial que genera una importante morbilidad y puede complicar el curso clínico en el paciente post trauma, con incremento en los requerimientos intrahospitalario, medidas invasivas de drenaje, cobertura antibiótica, manejo quirúrgico, hospitalización en UCI, y a largo plazo, las secuelas ya conocidas de fibrotórax, y afectación en calidad de vida post quirúrgico. Algunas de estas causas son propias del paciente, que, aunque le generan riesgo, no pueden ser alteradas, sin embargo, existen algunas condiciones que sí pueden ser modificables o al menosidentificadas adecuadamente; de tal manera que el estudio de estas condiciones puedeesclarecer cuales cambios en el abordaje inicial o esfuerzos terapéuticos, tendrían un impacto en disminuir la incidencia de esta complicación.
Este trabajo observacional, consiste en la revisión de los expedientes de pacientes con diagnóstico de empiema postraumático, en el HSJD, sus factores asociados, análisis estadístico, y revisión bibliográfica.