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1.
Braz J Psychiatry ; 43(6): 584-589, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33825763

RESUMEN

OBJECTIVE: To evaluate the association of leisure-time physical activity and sedentary behavior with body image concern and satisfaction in Brazilian adolescents. METHODS: Data were extracted from the 2015 Brazilian National Adolescent School-based Health Survey (Pesquisa Nacional de Saúde do Escolar [PeNSE]). Information regarding body image concern and satisfaction, as well as exposures (physical activity and sedentary behavior) and covariates (maternal education, age, smoking, and alcohol intake), were assessed through a questionnaire. RESULTS: Logistic regression analysis revealed that engagement in recommended levels of physical activity (≥ 300 min/week) was associated with a decreased concern with body image and a high satisfaction in boys. Four or more hours spent in sedentary activities were associated with increased concern with body image and dissatisfaction among boys and girls. CONCLUSION: These findings support the relevance of programs aiming to promote physical activity and reduce sedentary behavior in the adolescent population. Such programs play a protective role against body dissatisfaction and are important for the development of a healthy body image in adolescence.


Asunto(s)
Imagen Corporal , Conducta Sedentaria , Adolescente , Estudios Transversales , Ejercicio Físico , Femenino , Encuestas Epidemiológicas , Humanos , Actividades Recreativas , Masculino , Instituciones Académicas
2.
Metab Brain Dis ; 34(4): 1207-1219, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30949952

RESUMEN

Deficiency of hepatic enzyme tyrosine aminotransferase characterizes the innate error of autosomal recessive disease Tyrosinemia Type II. Patients may develop neurological and developmental difficulties due to high levels of the amino acid tyrosine in the body. Mechanisms underlying the neurological dysfunction in patients are poorly known. Importantly, Tyrosinemia patients have deficient Omega-3 fatty acids (n-3 PUFA). Here, we investigated the possible neuroprotective effect of the treatment with n-3 PUFA in the alterations caused by chronic administration of L-tyrosine on important parameters of energetic metabolism and oxidative stress in the hippocampus, striatum and cerebral cortex of developing rats. Chronic administration of L-tyrosine causes a decrease in the citrate synthase (CS) activity in the hippocampus and cerebral cortex, as well as in the succinate dehydrogenase (SDH) and isocitrate dehydrogenase (IDH) activities, and an increase in the α-ketoglutarate dehydrogenase activity in the hippocampus. Moreover, in the striatum, L-tyrosine administration caused a decrease in the activities of CS, SDH, creatine kinase, and complexes I, II-III and IV of the mitochondrial respiratory chain. We also observed that the high levels of L-tyrosine are related to oxidative stress in the brain. Notably, supplementation of n-3 PUFA prevented the majority of the modifications caused by the chronic administration of L-tyrosine in the cerebral enzyme activities, as well as ameliorated the oxidative stress in the brain regions of rats. These results indicate a possible neuroprotective and antioxidant role for n-3 PUFA and may represent a new therapeutic approach and potential adjuvant therapy to Tyrosinemia Type II individuals.


Asunto(s)
Encéfalo/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Ácidos Grasos Omega-3/farmacología , Mitocondrias/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Tirosina/farmacología , Animales , Aromatasa/metabolismo , Encéfalo/metabolismo , Masculino , Mitocondrias/metabolismo , Ratas , Ratas Wistar
3.
Metab Brain Dis ; 34(3): 941-950, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30919245

RESUMEN

The present study aimed to evaluate the effects of resveratrol on behavior and oxidative stress parameters in the brain of rats submitted to the animal model of mania induced by m-AMPH. In the first model (reversal treatment), rats received intraperitoneal (i.p.) injection of saline or m-AMPH (1 mg/kg body weight) once a day for 14 days, and from the 8th to the 14th day, they were orally treated with water or resveratrol (15 mg/kg), once a day. In the second model (maintenance treatment), rats were orally pretreated with water or resveratrol (15 mg/kg) once a day, and from the 8th to the 14th day, they received saline or m-AMPH i.p., once a day. Locomotor and exploratory activities were assessed in the open-field test. Oxidative and nitrosative damage parameters to lipid and proteins were evaluated by TBARS, 4-HNE, carbonyl, and 3-nitrotyrosine in the brain submitted to the experimental models. m-AMPH administration increased the locomotor and exploratory activities; resveratrol was not able to reverse or prevent these manic-like behaviors. Additionally, m-AMPH increased the lipid and protein oxidation and nitrosylation in the frontal cortex, hippocampus, and striatum of rats. However, resveratrol prevented and reversed the oxidative and nitrosative damage to proteins and lipids in all cerebral areas assessed. Since oxidative stress plays an important role in BD pathophysiology, supplementation of resveratrol in BD patients could be regarded as a possible adjunctive treatment with mood stabilizers.


Asunto(s)
Trastorno Bipolar/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Resveratrol/farmacología , Animales , Antimaníacos/farmacología , Encéfalo/metabolismo , Estimulantes del Sistema Nervioso Central/farmacología , Modelos Animales de Enfermedad , Masculino , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/uso terapéutico , Ratas Wistar
4.
Neurotox Res ; 34(4): 769-780, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29417439

RESUMEN

Tyrosinemia type II is an inborn error of metabolism caused by a deficiency in the activity of the enzyme tyrosine aminotransferase, leading to tyrosine accumulation in the body. Although the mechanisms involved are still poorly understood, several studies have showed that higher levels of tyrosine are related to oxidative stress and therefore may affect the cholinergic system. Thus, the aim of this study was to investigate the effects of chronic administration of L-tyrosine on choline acetyltransferase activity (ChAT) and acetylcholinesterase (AChE) in the brain of rats. Moreover, we also examined the effects of one antioxidant treatment (N-acetylcysteine (NAC) + deferoxamine (DFX)) on cholinergic system. Our results showed that the chronic administration of L-tyrosine decreases the ChAT activity in the cerebral cortex, while the AChE activity was increased in the hippocampus, striatum, and cerebral cortex. Moreover, we found that the antioxidant treatment was able to prevent the decrease in the ChAT activity in the cerebral cortex. However, the increase in AChE activity induced by L-tyrosine was partially prevented the in the hippocampus and striatum, but not in the cerebral cortex. Our results also showed no differences in the aversive and spatial memory after chronic administration of L-tyrosine. In conclusion, the results of this study demonstrated an increase in AChE activity in the hippocampus, striatum, and cerebral cortex and an increase of ChAT in the cerebral cortex, without cognitive impairment. Furthermore, the alterations in the cholinergic system were partially prevented by the co-administration of NAC and DFX. Thus, the restored central cholinergic system by antioxidant treatment further supports the view that oxidative stress may be involved in the pathophysiology of tyrosinemia type II.


Asunto(s)
Acetilcolinesterasa/metabolismo , Antioxidantes/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Colina O-Acetiltransferasa/metabolismo , Tirosina/toxicidad , Acetilcisteína/farmacología , Animales , Reacción de Prevención/efectos de los fármacos , Reacción de Prevención/fisiología , Deferoxamina/farmacología , Masculino , Memoria/efectos de los fármacos , Memoria/fisiología , Fármacos Neuroprotectores/farmacología , Ratas Wistar
5.
Rev. bras. farmacogn ; 17(2): 181-185, abr.-jun. 2007. ilus, tab
Artículo en Inglés | LILACS | ID: lil-456987

RESUMEN

In this paper we report the results of an in vitro study involving the influence of biflorin (an o-quinone isolated from Capraria biflora L. that has potent antimicrobial activity) on the Tc-99m labeling of red blood cells, plasma protein, cells protein, and lymphocytes. Blood was withdrawn from Wistar rats and incubated with various concentrations of biflorin, and solutions of stannous chloride and Tc-99m were added. Plasma (P) and red blood cells (RBC) were isolated, precipitated, and centrifuged, and soluble (SF) and insoluble (IF) fractions were isolated. The results show that the highest concentration (100 percent) of biflorin is able to reduce the uptake of Tc-99m ( percentATI) on RBC and the fixation on IF-P. To study the influence of biflorin on 99mTc lymphocyte labeling, human blood was submitted to a technique with Ficoll-Hypac and centrifuged, and white cells were isolated. Lymphocytes (2.5 mL; 1.0 x 10(6) cells/mL) were obtained and a 0.2 mL solution was incubated with biflorin (0.1 mL). Solutions of stannous chloride and 99mTc were added. Lymphocytes were separated and the percentATI bound in these cells was evaluated. A reduction in percentATI (from 97.85 ± 0.99 to 88.86 ± 5) was observed for RBC and for IF-P (73.24 ± 5.51 to 20.72 ± 6.95). In this case the results showed no decrease in percentATI for the lymphocytes with biflorin.


Neste artigo relatam-se os resultados de um estudo in vitro envolvendo a influência da biflorina (uma o-quinona isolada de Capraria biflora L. que possui uma potente atividade antimicrobiana) na marcação do Tc-99m em células vermelhas do sangue, proteínas do plasma, proteínas celulares e em linfócitos. O sangue foi coletado de ratos Wistar e incubado com várias concentrações de biflorina, e soluções de cloreto estanoso (SnCl2) adicionando-se Tc-99m. O plasma (P) e as células vermelhas do sangue (CVS) foram isolados, precipitados e centrifugados, isolando-se as frações solúveis (FS) e insolúveis (FI). A maior concentração de biflorina (100 por cento) é capaz de reduzir a captação do Tc-99m ( por centoATI) nas CVS e a fixação na FI-P. Uma solução de 0,2 mL de linfócitos (2,5 mL; 1.0 x 10(6) células/mL), obtidos por centrifugação de sangue humano tratado com Ficoll-Hypac, foi incubada com biflorina (0,1 mL). Soluções de cloreto estanoso e Tc-99m foram então adicionadas. Os linfócitos foram separados e o por centoATI presente nessas células foi avaliado. Uma redução no por centoATI (de 97,85 ± 0,99 a 88,86 ± 5) foi observada para CVS e para FI-P (73,24 ± 5,51 a 20,72 ± 6,95). Os resultados não mostraram decréscimo no por centoATI para os linfócitos com biflorina.


Asunto(s)
Animales , Ratas , Técnicas In Vitro , Plantas Medicinales , Radiofármacos
6.
Mem Inst Oswaldo Cruz ; 97(3): 307-11, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12048556

RESUMEN

The Mojuí dos Campos virus (MDCV) was isolated from the blood of an unidentified bat (Chiroptera) captured in Mojuí dos Campos, Santarém, State of Pará, Brazil, in 1975 and considerated to be antigenically different from other 102 arboviruses belonging to several antigenic groups isolated in the Amazon region or another region by complement fixation tests. The objective of this work was to develop a morphologic, an antigenic and physicochemical characterization of this virus. MDCV produces cytopathic effect in Vero cells, 24 h post-infection (p.i), and the degree of cellular destruction increases after a few hours. Negative staining electron microscopy of the supernatant of Vero cell cultures showed the presence of coated viral particles with a diameter of around 98 nm. Ultrathin sections of Vero cells, and brain and liver of newborn mice infected with MDCV showed an assembly of the viral particles into the Golgi vesicles. The synthesis kinetics of the proteins for MDCV were similar to that observed for other bunyaviruses, and viral proteins could be detected as early as 6 h p.i. Our results reinforce the original studies which had classified MDCV in the family Bunyaviridae, genus Bunyavirus as an ungrouped virus, and it may represent the prototype of a new serogroup.


Asunto(s)
Bunyaviridae/ultraestructura , Quirópteros/virología , Animales , Brasil , Bunyaviridae/química , Infecciones por Bunyaviridae/virología , Chlorocebus aethiops , Ratones , Microscopía Electrónica , Proteínas Quinasas/biosíntesis , Células Vero/ultraestructura
7.
Arch. argent. dermatol ; 35(4): 221-30, jul.-ago. 1985. ilus
Artículo en Español | LILACS | ID: lil-2204

RESUMEN

Se presentan los hallazgos clínicos, histopatológicos, ultraestructurales e inmunológicos en un paciente con lepromas histoides de Wade (lepromas fusocelulares). Teniendo en cuenta que el enfermo presentaba alternaciones de la visión y que tenía hermanos con problemas similares, se completa el estudio con una investigación inmunológica familiar. Se concluye que este tipo de leproma se observa en pacientes bacilíferos, lepromatosos o dimorfos, como fenómeno inicial o de recaída, tratándose de una lesión hiperreactiva, donde a la falla en los linfocitos T posiblemente se le sume algún factor tisular local (metabólico?) condicionante


Asunto(s)
Adulto , Humanos , Masculino , Tuberculosis Ganglionar/patología , Linfocitos T , Tuberculosis Ganglionar/inmunología
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