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1.
Reprod Domest Anim ; 59(4): e14564, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38634152

RESUMEN

In this longitudinal study, the anti-Müllerian hormone (AMH) levels in blood were determined in 32 Murrah buffalo females at 8, 10, 12, 16 and 19 months of age when females were synchronized and the antral follicular population (AFP) was estimated. Correlations of AFP to the AMH level at 19 months of age and retrospectively to younger ages were investigated. Then females were split into high and low AFP, and their AMH levels were compared for all ages and tested as predictors of AFP categories. The highest AMH level (p < .05) was detected at 8 months, reducing but not differing (p > .05) at 10, 12 and 16 months then reducing again (p < .05) at 19 months of age. The mean AFP was 17.6 ± 6.3 follicles, and it was positively correlated with AMH in all ages tested. High AFP females had approximately two times more antral follicles than low AFP (p < .05) and their AMH levels were higher (p < .01) than in low AFP ones in all ages. Only at 8 months, AMH levels can be used to precociously detect high AFP heifers (a cut-off point of 464.7 pg/mL; p < .05), while low AFP heifers could be detected by AMH measurements at 8, 10, 12 and 16 months of age (p < .05). We conclude that AMH of buffalo calves correlates with AFP of heifers later in life and depending on the age, its levels could be used to identify future females with low or high AFP.


Asunto(s)
Hormona Antimülleriana , Hormonas Peptídicas , Femenino , Animales , Bovinos , Búfalos , Estudios Longitudinales , Estudios Retrospectivos , alfa-Fetoproteínas
2.
J Pediatr ; 242: 137-144.e4, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34798080

RESUMEN

OBJECTIVE: We hypothesized that a cumulative heart rate characteristics (HRC) index in real-time throughout the neonatal intensive care unit (NICU) hospitalization, alone or combined with birth demographics and clinical characteristics, can predict a composite outcome of death or neurodevelopmental impairment (NDI). STUDY DESIGN: We performed a retrospective analysis using data from extremely low birth weight infants who were monitored for HRC during neonatal intensive care. Surviving infants were assessed for NDI at 18-22 months of age. Multivariable predictive modeling of subsequent death or NDI using logistic regression, cross-validation with repeats, and step-wise feature elimination was performed each postnatal day through day 60. RESULTS: Among the 598 study participants, infants with the composite outcome of death or moderate-to-severe NDI had higher mean HRC scores during their stay in the NICU (3.1 ± 1.8 vs 1.3 ± 0.8; P < .001). Predictive models for subsequent death or NDI were consistently higher when the cumulative mean HRC score was included as a predictor variable. A parsimonious model including birth weight, sex, ventilatory status, and cumulative mean HRC score had a cross-validated receiver-operator characteristic curve as high as 0.84 on days 4, 5, 6, and 8 and as low as 0.78 on days 50-52 and 56-58 to predict subsequent death or NDI. CONCLUSIONS: In extremely low birth weight infants, higher mean HRC scores throughout their stay in the NICU were associated with a higher risk of the composite outcome of death or NDI. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00307333.


Asunto(s)
Recien Nacido con Peso al Nacer Extremadamente Bajo , Unidades de Cuidado Intensivo Neonatal , Peso al Nacer , Frecuencia Cardíaca/fisiología , Humanos , Lactante , Recién Nacido , Estudios Retrospectivos
3.
Front Microbiol ; 10: 2567, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31798545

RESUMEN

S. mitis is an abundant member of the commensal microbiota of the oral cavity and pharynx, which has the potential to promote systemic infections. By analyzing a collection of S. mitis strains isolated from the oral cavity at commensal states or from systemic infections (blood strains), we established that S. mitis ubiquitously express the surface immunodominant protein, PcsB (also called GbpB), required for binding to sucrose-derived exopolysaccharides (EPS). Immuno dot blot assays with anti-PcsB antibodies and RT-qPCR transcription analyses revealed strain-specific profiles of PcsB production associated with diversity in pcsB transcriptional activities. Additionally, blood strains showed significantly higher levels of PcsB expression compared to commensal isolates. Because Streptococcus mutans co-colonizes S. mitis dental biofilms, and secretes glucosyltransferases (GtfB/C/D) for the synthesis of highly insoluble EPS from sucrose, profiles of S. mitis binding to EPS, biofilm formation and evasion of the complement system were assessed in sucrose-containing BHI medium supplemented or not with filter-sterilized S. mutans culture supernatants. These analyses showed significant S. mitis binding to EPS and biofilm formation in the presence of S. mutans supernatants supplemented with sucrose, compared to BHI or BHI-sucrose medium. In addition, these phenotypes were abolished if strains were grown in culture supernatants of a gtfBCD-defective S. mutans mutant. Importantly, GtfB/C/D-associated phenotypes were enhanced in high PcsB-expressing strains, compared to low PcsB producers. Increased PcsB expression was further correlated with increased resistance to deposition of C3b/iC3b of the complement system after exposure to human serum, when strains were previously grown in the presence of S. mutans supernatants. Finally, analyses of PcsB polymorphisms and bioinformatic prediction of epitopes with significant binding to MHC class II alleles revealed that blood isolates harbor PcsB polymorphisms in its functionally conserved CHAP-domain, suggesting antigenic variation. These findings reveal important roles of PcsB in S. mitis-host interactions under commensal and pathogenic states, highlighting the need for studies to elucidate mechanisms regulating PcsB expression in this species.

4.
J Pediatr ; 198: 162-167, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29703576

RESUMEN

OBJECTIVE: To examine the effect of heart rate characteristics (HRC) monitoring on length of stay among very low birth weight (VLBW; <1500 g birth weight) neonates in the HeRO randomized controlled trial (RCT). STUDY DESIGN: We performed a retrospective analysis of length of stay metrics among 3 subpopulations (all patients, all survivors, and survivors with positive blood or urine cultures) enrolled in a multicenter, RCT of HRC monitoring. RESULTS: Among all patients in the RCT, infants randomized to receive HRC monitoring were more likely than controls to be discharged alive and prior to day 120 (83.6% vs 80.1%, P = .014). The postmenstrual age at discharge for survivors with positive blood or urine cultures was 3.2 days lower among infants randomized to receive HRC monitoring when compared with controls (P = .026). Although there were trends in other metrics toward reduced length of stay in HRC-monitored patients, none reached statistical significance. CONCLUSIONS: HRC monitoring is associated with reduced mortality in VLBW patients and a reduction in length of stay among infected surviving VLBW infants. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00307333.


Asunto(s)
Determinación de la Frecuencia Cardíaca , Frecuencia Cardíaca/fisiología , Unidades de Cuidado Intensivo Neonatal , Tiempo de Internación , Femenino , Humanos , Recién Nacido , Recién Nacido de muy Bajo Peso , Masculino , Alta del Paciente , Estudios Retrospectivos
5.
Cell Reprogram ; 14(3): 217-24, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22686478

RESUMEN

Cell death by apoptosis is considered to be irreversible. However, reports have indicated that its reversibility is possible if the cells have not yet reached the "point of no return." In order to add new information about this topic, we used cells at different moments of apoptotic process as nuclear donors in somatic cell nuclear transfer (SCNT) in order to test if programmed cell death can be reversed. Adult bovine fibroblasts were treated with 10 µM of staurosporine (STP) for 3 h and analyzed for phosphatidylserine externalization (Annexin assay) and presence of active caspase-9. Annexin-positive (Anx+) and Caspase-9-positive (Casp-9+) cells were isolated by FACS and immediately transferred into enucleated in vitro matured bovine oocytes. After STP treatment, 89.9% of cells were Anx+ (4.6% in control cells; p<0.01) and 24.9% were Casp-9+ (2.4% in control cells; p<0.01). Fusion and cleavage were not affected by the use apoptotic cells (p>0.05). Also, the use of Anx+ cells did not affect blastocyst production compared to control (26.4% vs. 22.9%, respectively; p>0.05). However, blastocyst formation was affected by the use of Casp-9+ cells (12.3%; p<0.05). These findings contribute to the idea of that apoptosis is reversible only at early stages. Additionally, we hypothesize that the "point of no return" for apoptosis may be located around activation of Caspase-9.


Asunto(s)
Apoptosis , Bovinos , Reprogramación Celular/fisiología , Fibroblastos/fisiología , Técnicas de Transferencia Nuclear , Animales , Apoptosis/fisiología , Bovinos/embriología , Núcleo Celular/genética , Núcleo Celular/metabolismo , Núcleo Celular/fisiología , Células Cultivadas , Clonación de Organismos/métodos , Clonación de Organismos/veterinaria , Desarrollo Embrionario/genética , Femenino , Fibroblastos/citología , Citometría de Flujo , Etiquetado Corte-Fin in Situ , Técnicas de Transferencia Nuclear/veterinaria , Cultivo Primario de Células
6.
Cloning Stem Cells ; 11(4): 565-73, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19780697

RESUMEN

Cell cycle synchronization by serum starvation (SS) induces apoptosis in somatic cells. This side effect of SS is hypothesized to negatively affect the outcome of somatic cell nuclear transfer (SCNT). We determined whether apoptotic fibroblasts affect SCNT yields. Serum-starved, adult, bovine fibroblasts were stained with annexin V-FITC/propidium iodide to allow apoptosis detection by flow cytometry. Positive and negative cells sorted by fluorescence activated cell sorting (FACS) and an unsorted control group were used as nuclear donors for SCNT. Reconstructed embryos were cultured in vitro and transferred to synchronized recipients. Apoptosis had no effect on fusion and cleavage rates; however, it resulted in reductions in blastocyst production and quality measured by apoptotic index. However, reconstructed embryos with apoptotic cells resulted in pregnancy rates similar to that of the control on day 30, and generated one live female calf. In conclusion, we showed that apoptotic cells present in serum-starved cultures negatively affect embryo production after SCNT without compromising full-term development. Further studies will evaluate the ability of the oocyte to reprogram cells in specific phases of apoptosis.


Asunto(s)
Apoptosis/fisiología , Blastocisto/citología , Clonación de Organismos/métodos , Desarrollo Embrionario , Desarrollo Fetal , Fibroblastos/patología , Oocitos/citología , Animales , Bovinos , Ciclo Celular , Núcleo Celular/genética , Proliferación Celular , Reprogramación Celular , Medio de Cultivo Libre de Suero , Femenino , Técnicas de Transferencia Nuclear , Oocitos/fisiología , Partenogénesis , Embarazo , Índice de Embarazo
7.
Clin Vaccine Immunol ; 14(6): 804-7, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17475767

RESUMEN

In a follow-up study of children infected with Streptococcus mutans at an early age (children previously shown to respond poorly to S. mutans GbpB), there was a delay in their immune response, rather than a complete inability to respond to this antigen. Epitopes in the N-terminal third of GbpB were identified as targets for naturally induced immunoglobulin A antibody in children at an early age.


Asunto(s)
Factores de Edad , Inmunoglobulina A Secretora/análisis , Saliva/inmunología , Infecciones Estreptocócicas/inmunología , Streptococcus mutans/inmunología , Estudios de Casos y Controles , Preescolar , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente Indirecta , Estudios de Seguimiento , Humanos , Inmunoglobulina A Secretora/inmunología , Estudios Longitudinales
8.
Pediatr. día ; 10(2): 93-7, mayo-jun. 1994.
Artículo en Español | LILACS | ID: lil-137986

RESUMEN

Las recomendaciones enbozadas en este programa son ambiciosas pero la naturaleza del problema en Chile lo requiere. Hay pocos problemas de salud pública que tocan a tantos chilenos como lo hacen los accidentes. Algo que también hace diferente el tema, es el amplio número de disciplinas interrelacionadas en el control de esta epidemia. Una intervención, comienza con el conocimiento capitalizado durante las fases de vigilancia e investigación, para determinar el cómo, quién y porqué de un accidente. Todos tenemos nuestra parte en este gran desafío. Como comunidad, debemos proveernos los recursos y apoyar a nuestros líderes, creando conciencia en el núcleo que nos rodea


Asunto(s)
Prevención de Accidentes , Programas Nacionales de Salud , Desarrollo de Programa , Accidentes de Tránsito/prevención & control , Accidentes Domésticos/prevención & control , Accidentes de Trabajo/prevención & control , Centros de Rehabilitación/legislación & jurisprudencia , Chile , Prevención Primaria/legislación & jurisprudencia
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