Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Braz J Med Biol Res ; 56: e12811, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37792779

RESUMEN

The present study aims to investigate if Cimicifuga racemosa (L.) Nutt extract (CIMI) reduces deleterious effects of dexamethasone (DEXA) in ovaries cultured in vitro. Mouse ovaries were collected and cultured in DMEM+ only or supplemented with 5 ng/mL of CIMI, or 4 ng/mL DEXA, or both CIMI and DEXA. The ovaries were cultured at 37.5°C in 5% CO2 for 6 days. Ovarian morphology, follicular ultrastructure, and the levels of mRNA for Bax, Bcl-2, and Caspase-3 were evaluated. The results showed that DEXA reduced the percentage of morphologically normal follicles, while CIMI prevented the deleterious effects caused by DEXA. In addition, DEXA negatively affected the stromal cellular density, while CIMI prevented these adverse effects. Ovaries cultured with DEXA and CIMI showed similar levels of mRNA for Bax, Bcl-2, and Caspase-3 compared to those cultured in control medium, while ovaries cultured with DEXA had increased expression of the above genes. Additionally, the ultrastructure of the ovaries cultured with CIMI was well preserved. Thus, the extract of CIMI was able to prevent the deleterious effects caused by DEXA on cultured mouse ovaries.


Asunto(s)
Cimicifuga , Femenino , Animales , Ratones , Caspasa 3 , Proteína X Asociada a bcl-2/metabolismo , Proteína X Asociada a bcl-2/farmacología , Cimicifuga/genética , Cimicifuga/metabolismo , Folículo Ovárico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/farmacología , ARN Mensajero/metabolismo , Dexametasona/toxicidad
2.
Zygote ; 31(4): 305-315, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37221099

RESUMEN

Preantral to early antral follicles transition is a complex process regulated by endocrine and paracrine factors, as well as by a precise interaction among oocyte, granulosa cells and theca cells. Understanding the mechanisms that regulate this step of folliculogenesis is important to improve in vitro culture systems, and opens new perspectives to use oocytes from preantral follicles for assisted reproductive technologies. Therefore, this review aims to discuss the endocrine and paracrine mechanisms that control granulosa cell proliferation and differentiation, formation of the antral cavity, estradiol production, atresia, and follicular fluid production during the transition from preantral to early antral follicles. The strategies that promote in vitro growth of preantral follicles are also discussed.


Asunto(s)
Células de la Granulosa , Folículo Ovárico , Femenino , Animales , Oocitos , Estradiol , Proliferación Celular
3.
Braz. j. med. biol. res ; 56: e12811, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1513882

RESUMEN

The present study aims to investigate if Cimicifuga racemosa (L.) Nutt extract (CIMI) reduces deleterious effects of dexamethasone (DEXA) in ovaries cultured in vitro. Mouse ovaries were collected and cultured in DMEM+ only or supplemented with 5 ng/mL of CIMI, or 4 ng/mL DEXA, or both CIMI and DEXA. The ovaries were cultured at 37.5°C in 5% CO2 for 6 days. Ovarian morphology, follicular ultrastructure, and the levels of mRNA for Bax, Bcl-2, and Caspase-3 were evaluated. The results showed that DEXA reduced the percentage of morphologically normal follicles, while CIMI prevented the deleterious effects caused by DEXA. In addition, DEXA negatively affected the stromal cellular density, while CIMI prevented these adverse effects. Ovaries cultured with DEXA and CIMI showed similar levels of mRNA for Bax, Bcl-2, and Caspase-3 compared to those cultured in control medium, while ovaries cultured with DEXA had increased expression of the above genes. Additionally, the ultrastructure of the ovaries cultured with CIMI was well preserved. Thus, the extract of CIMI was able to prevent the deleterious effects caused by DEXA on cultured mouse ovaries.

4.
Zygote ; 29(4): 301-306, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33597054

RESUMEN

This study aimed to investigate the effects of eugenol on growth, viability, antrum formation and mRNA expression of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase 1 (GPX1) and peroxiredoxin 6 (PRDX6) in bovine secondary follicles cultured in vitro. To this end, bovine ovaries were collected from a local slaughterhouse and in the laboratory the follicles were isolated from the ovarian cortex. The follicles were then cultured in TCM-199+ alone or supplemented with different concentrations of eugenol (0.5, 5.0 and 50.0 µM). Follicular diameters and antrum formation were evaluated on days 0, 6, 12 and 18. Viability analysis was performed using calcein and ethidium homodimer. Real-time PCR was used to quantify mRNA levels for SOD, CAT, GPX1 and PRDX6 in cultured follicles. Follicular diameters and mRNA levels in follicles cultured in vitro were compared using analysis of variance and Kruskal-Wallis tests, while follicular survival and antrum formation were compared using the chi-squared test (P < 0.05). The results showed that secondary follicles cultured with eugenol maintained similar morphology and viability to follicles cultured in the control group. A progressive increase in follicular diameter was observed between days 0 and 12 for all treatments, except for follicles cultured with 50 µM eugenol. Eugenol (5.0 and 50.0 µM) increased mRNA levels for GPX1 in cultured follicles, but 0.5 µM eugenol reduced mRNA levels for SOD. The addition of eugenol did not influence mRNA expression for CAT and PRDX6. In conclusion, eugenol supplementation reduces mRNA levels for SOD and increases mRNA levels of GPX1 in bovine secondary follicles cultured in vitro.


Asunto(s)
Folículo Ovárico , Animales , Bovinos , Eugenol/farmacología , Femenino , Glutatión Peroxidasa , ARN Mensajero/genética , Superóxido Dismutasa/genética , Glutatión Peroxidasa GPX1
5.
Osteoporos Int ; 31(5): 905-912, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31897546

RESUMEN

The congenital adrenal hyperplasia population seems to have an intrinsic tendency to a high frequency of low bone mass. However in this single-center and long-term evaluated cohort, the simplified corticoid regimen, with exclusive dexamethasone single dose reposition during adulthood, did not represent a risk factor for decrease in bone health. INTRODUCTION: The impact of long-term and supposedly physiological doses of gluco and mineralocorticoid (GC/MC) on bone mineral density (BMD) in congenital adrenal hyperplasia (CAH) remains discordant among studies, which contain different clinical forms and corticoid regimens. Our aim was to evaluate the BMD in CAH adults receiving similar GC regimen since childhood and to correlate it with GC/MC cumulative doses. METHODS: Only patients with good compliance, who used cortisone acetate (CA) during childhood and dexamethasone after the final height achievement. Cumulative GC/MC doses were calculated from diagnosis until last evaluation. BMD was analyzed by the first and last energy X-ray absorptiometry (DXA) scans performed. RESULTS: Twenty simple virilizing (SV) and 14 salt wasting (WS) whose mean age was 26 ± 6 years, mean CA, dexamethasone, and fludrocortisone cumulative doses were 63,813 ± 32,767, 812 ± 558, and 319 ± 325 mg/m2, respectively. Based on the last DXA, low BMD was observed in 11% of patients, total hip Z-score was lower in the SW than SV form (p = 0.04). Cumulative CA dose had an inverse correlation with femoral neck Z-score (p < 0.01). Total cumulative GC and MC doses had an inverse correlation with total hip Z-score (p < 0.01). In the analysis of sequential BMD during dexamethasone therapy, no association was observed among cumulative GC/MC doses, clinical forms, sex, and lumbar Z-score delta. CONCLUSIONS: Even though a low CA regimen during growth periods in addition to MC replacement appears to have an influence on BMD at femoral sites, interestingly a low dexamethasone one does not seem to be deleterious for bone health in adulthood.


Asunto(s)
Hiperplasia Suprarrenal Congénita , Densidad Ósea , Absorciometría de Fotón , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Adulto , Niño , Glucocorticoides/efectos adversos , Humanos , Estudios Retrospectivos , Adulto Joven
6.
Int Endod J ; 52(2): 223-236, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30107037

RESUMEN

AIM: To evaluate artefact intensity in cone beam computed tomography (CBCT) images of two alloys used in metal posts scanned using different exposure parameters. METHODOLOGY: The sample consisted of 20 single-rooted teeth divided into two groups for use with either a NiCr post or AgPd post. All teeth were scanned with and without their corresponding metal posts and with and without the presence of an extra restored tooth in the arch. The samples were scanned using CS 9000 3D scanner with two exposure protocols: 85 kV 6.3 mA and 85 kV 10 mA. Voxel size and FOV were fixed at 0.100 mm and 5 cm × 3.75 cm. The presence of artefacts was assessed qualitatively by two calibrated observers using the CBCT volume and paired 2D images, and quantitatively by one trained observer, using ImageJ software. Wilcoxon's signed rank, Mann-Whitney, kappa and chi-square tests were used for qualitative analyses. Two-way anova and Tukey's tests were used for quantitative analyses. All analyses were conducted considering the 95% confidence level (α < 0.05). RESULTS: For the CBCT volume qualitative analysis, significant differences were observed between the metal alloys in the presence of an extra restored tooth, with higher artefact intensity for AgPd when assessing hypodense halos and lines (P = 0.006). Images with two restored teeth had significantly more hypodense and hyperdense lines (P = 0.033). When evaluating exposure parameters and number of restored teeth, the paired image quality analysis revealed significant disagreement between observers for diagnostic image quality (P = 0.001). Quantitative artefact analysis revealed higher artefact intensity for the AgPd posts in the presence of two restored teeth. CONCLUSION: Although the exposure parameters tested did not interfere with artefact intensity, post alloys with a higher atomic number and the presence of another metal structure in the arch increased artefact intensity and impaired the diagnostic quality of CBCT images.


Asunto(s)
Artefactos , Tomografía Computarizada de Haz Cónico/métodos , Aleaciones Dentales/química , Metales/química , Técnica de Perno Muñón , Raíz del Diente/diagnóstico por imagen , Diente Premolar/diagnóstico por imagen , Aleaciones de Cromo/química , Humanos , Imagenología Tridimensional , Programas Informáticos , Fracturas de los Dientes/diagnóstico por imagen , Raíz del Diente/lesiones
7.
Mol Biochem Parasitol ; 188(2): 87-90, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23603359

RESUMEN

Selenium (Se) is an essential trace element primarily found in selenoproteins as the 21st amino acid (selenocysteine, Sec, or U). Selenoproteins play an important role in growth and proliferation and are typically involved in cellular redox balance. Selenocysteine is encoded by an in-frame UGA codon specified by a stem-loop structure, the Sec insertion sequence element (SECIS), which, in eukaryotes, is located in the 3'-untranslated region (UTR). The availability of the Naegleria gruberi (ATCC 30224) genome sequence and the use of this organism as a model system for the pathogenic amoeba N. fowleri allowed us to investigate the Sec incorporation pathway in this primitive eukaryote. Using bioinformatics tools, we identified gene sequences encoding PSTK (O-phosphoseryl-tRNA(Sec) kinase), SepSecS (O-phosphoseryl-tRNA:selenocysteinyl-tRNA synthase), SelD/SPS2 (selenophosphate synthetase), EFSec (selenocysteine-specific elongation factor) and SBP (SECIS binding protein). These findings were confirmed by RT-PCR and by sequencing. A potential tRNA(Ser)Sec (SelC) gene and a putative selenoprotein with sequence similarity to a mitochondrial thioredoxin reductase (TR3) were also identified. Our results show that the selenocysteine incorporation machinery is indeed present in N. gruberi. Interestingly, the SelD/SPS2 gene is 2214 bp in length and contains two distinct domains. The N-terminal region shows sequence similarity to predicted methyltransferase proteins, and the C-terminal region is homologous to prokaryotic SelD/SPS2. Our results suggest the possibility of novel selenoproteins.


Asunto(s)
Vías Biosintéticas/genética , Naegleria/genética , Naegleria/metabolismo , Selenocisteína/biosíntesis , Selenoproteínas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Biología Computacional , Perfilación de la Expresión Génica , Genes Protozoarios , Modelos Moleculares , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Análisis de Secuencia de ADN
8.
Mol Biochem Parasitol ; 180(1): 47-50, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21723329

RESUMEN

Selenoproteins are characterized by the incorporation of at least one amino acid selenocysteine (Sec-U) encoded by in-frame UGA stop codons. These proteins, as well as the components of the Sec synthesis pathway, are present in members of the bacteria, archaea and eukaryote domains. Although not a ubiquitous pathway in all organisms, it was also identified in several protozoa, including the Kinetoplastida. Genetic evidence has indicated that the pathway is non-essential to the survival of Trypanosoma growing in non-stressed conditions. By analyzing the effects of RNA interference of the Trypanosoma brucei selenophosphate synthetase SPS2, we found a requirement under sub-optimal growth conditions. The present work shows that SPS2 is involved in oxidative stress protection of the parasite and its absence severely hampers the parasite survival in the presence of an oxidizing environment that results in an apoptotic-like phenotype and cell death.


Asunto(s)
Estrés Oxidativo , Fosfotransferasas/metabolismo , Proteínas Protozoarias/metabolismo , Trypanosoma brucei brucei/enzimología , Oxidación-Reducción , Fosfotransferasas/genética , Proteínas Protozoarias/genética , Selenio/metabolismo , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/metabolismo
9.
Braz. j. phys. ther. (Impr.) ; 10(2): 205-211, 2006. tab, graf
Artículo en Portugués | LILACS | ID: lil-433931

RESUMEN

OBJETIVO: Verificar a atividade e padrão eletroforético da LDH em resposta ao exercício em esteira em ratos submetidos à fotoestimulação por laser de baixa intensidade (780 etam). MÉTODO: Foram utilizados nesse estudo 54 ratos machos jovens (30dias), Winstar, com peso inicial médio de 112 ± 4,7g, os quais foram divididos em quatro grupos: dois permaneceram em repouso, GRC (grupo repouso controle, n= 9) e GRL (grupo repouso laser, n= 10), sendo o segundo irradiado por laser, e outros dois foram submetidos ao treinamento aeróbio e testes de esforço crescente em esteira (em degraus descontínuos) visando à determinação do limiar de anaerobiose (LA) durante 5 semanas, GEC (grupo exercício controle, n= 16) e GEL (grupo exercício laser, n= 19), sendo o último também irradiado por laser. O laser foi aplicado no quadríceps, glúteo máximo, sóleo e tibial anterior (TA), bilateralmente, imediatamente após cada sessão de treinamento, usando: 3,8J/cm², 15mW, 10s, modo contínuo, durante 5 semanas. Amostras de sóleo, TA e coração foram removidas 48 horas após a última sessão de exercício para análise eletroforética e espectrofotométrica. A estatística foi realizada através do teste ANOVA e post-hoc de TUKEY. O nível de significância foi considerado (p< 0,05). RESULTADOS: Foram observadas reduções na atividade da LDH causadas pelo laser (de 19 por cento a 30 por cento), exercício (de 41 por cento a 66 por cento) e as ações combinadas (de 47 por cento a 66 por cento) (p< 0,01). A eletroforese mostrou uma predominância da subunidade B para o sóleo e coração, e uma predominância da subunidade A no TA. CONCLUSÕES: Estes dados sugerem uma melhor resposta adaptativa dos animais ao treinamento aeróbio associado à terapia laser, no que se refere à otimização da via oxidativa.


Asunto(s)
Animales , Ratas , Prueba de Esfuerzo , Terapia por Luz de Baja Intensidad , Modalidades de Fisioterapia , Ratas Wistar
10.
Bull World Health Organ ; 76(4): 385-91, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9803589

RESUMEN

Reported is an evaluation of 13 years of intervention by the Chagas Disease Control Programme in an endemic area (Montalvania) in the State of Minas Gerais, Brazil. The design used was an epidemiological panel study. The reduction of Trypanosoma cruzi infection rates was estimated from data collected on three separate occasions: a serological survey in 1975-80, a quasi-experimental study in 1987, and the present investigation. A random sample of 156 households was selected and blood samples were collected from 653 inhabitants. The data routinely collected by the control programme were analysed to correlate the results with the incidence of T. cruzi. The overall prevalence of infection was 2.3%; however, no participant under 14 years of age was found to have a positive serological test. The total reduction in T. cruzi infection rates in this area from the start of the programme's activities was estimated to be 83.5%. Cross-sectional comparisons for the age groups 2-6 years and 7-14 years indicated a 100% reduction in T. cruzi incidence rates; but cohort comparisons showed that 100% reduction was achieved only for the 2-6-years age group.


PIP: The Chagas Disease Control Program in Brazil utilizes house spraying with insecticide to control the Triatoma bug population (the intermediate host of Trypanosoma cruzi). Serologic evaluations of selected cohorts have shown a reduction of T. cruzi infection among those born after the start of the national program. This article reports on an evaluation of the Chagas Disease Control Program in Montalvania (State of Minas Gerais), Brazil, conducted in 1995 after 13 years of interventions. Blood samples collected from 653 persons from 156 households revealed a prevalence of T. cruzi infection of 2.3%--an 83.5% reduction since 1987. Seroprevalences were zero in 1995 in the 1-6 and 7-14 year age groups, indicating an interruption in disease transmission. A significant reduction was also recorded in the age group 15-29 years. An earlier evaluation in this area had concluded that 5 years of interventions were not sufficient to produce changes in infection rates. The high proportion of mud houses with dirt floors and tile roofs--ideal conditions for triatomine colonization--indicates a need for continuing active and passive surveillance in this area.


Asunto(s)
Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/prevención & control , Adolescente , Animales , Anticuerpos Antiprotozoarios/análisis , Brasil/epidemiología , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Masculino , Factores Socioeconómicos , Trypanosoma cruzi/inmunología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...