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1.
Braz. j. med. biol. res ; 55: e11938, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1384138

RESUMO

The aim of this study was to assess the effect of two types of stressors, regarding the extent of involvement of ouabain (OUA), hippocampal sodium/potassium ATPase (NKA) expression, and the hippocampal corticosterone receptors (CR)/melatonin receptors (MR) expression ratio, on the behavioral and cardiovascular responses and on the hippocampal cornu ammonis zone 3 (CA3) and dentate gyrus (DG). Thirty adult male Wistar albino rats aged 7-8 months were exposed to either chronic immobilization or a disturbed dark/light cycle and treated with either ouabain or vehicle. In the immobilized group, in the absence of hippocampal corticosterone (CORT) changes, rats were non-responsive to stress, despite experiencing increased pulse rate, downregulated hippocampal sodium/potassium pump, and enhanced hippocampal CR/MR expression ratio. Prolonged darkness precipitated a reduced upright attack posture, with elevated CORT against hippocampal MR downregulation. Both immobilization and, to a lesser extent, prolonged darkness stress resulted in histopathological and ultrastructural neurodegenerative changes in the hippocampus. OUA administration did not change the behavioral resilience in restrained rats, despite persistence of the underlying biochemical derangements, added to decreased CORT. On the contrary, with exposure to short photoperiods, OUA reverted the behavior towards a combative reduction of inactivity, with unvaried CR/MR and CORT, while ameliorating hippocampal neuro-regeneration, with co-existing NKA and MR repressions. Therefore, the extent of OUA, hippocampal NKA expression, and CR/MR expression, and subsequent behavioral and cardiac responses and hippocampal histopathology, differ according to the type of stressor, whether immobilization or prolonged darkness.

2.
Chinese Journal of School Health ; (12): 243-246, 2020.
Artigo em Chinês | WPRIM | ID: wpr-810920

RESUMO

Objective@#To explore the relationship among dark triad, peer relationship, and cyber bullying of middle school students, and to provide suggestions for intervention of cyberbullying behavior of middle school students.@*Methods@#Peer Relationship Scale (PRS), Dirty Dozen (DD) and Cyberbullying Questionnaire (CBQ) were administrated to 1 934 middle school students in Beijing and Yunnan by cluster sampling.@*Results@#Middle school boys scored significantly higher on the dark triad and cyber-bullying than girls ( F =13.45, 50.20, P <0.01). The dark triad of middle school students was positively correlated with cyber-bullying ( r =0.38, 0.40, 0.21, P <0.01), while negative dimensions of peer relationship were positively correlated with cyber-bullying ( r = -0.10 , -0.22, -0.16, P <0.01). Peer relationship had a moderating effect on the relationship between dark triad and cyber-bullying ( β =-0.07, t =-3.24,Δ R 2=0.00, P <0.01).@*Conclusion@#Positive peer relationship can reduce the cyber-bullying behavior of middle school students with high dark triad which should be emphasized among middle school students.

3.
Braz. j. biol ; 79(3): 404-409, July-Sept. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1001466

RESUMO

Abstract Passion fruits species presents a larger economic importance for in natura consumption and industry. The main way to propagate these species is by seeds; however, the aril presence and environmental conditions may inhibit the seeds germination. In this sense, the objective of this study was to evaluate the effect of aril removal methods and light conditions on P. edulis var. flavicarpa seeds quality and germination. There were used five methods to remove the seeds aril: (1) friction on steel mesh sieve for 5 minutes; (2) friction with coarse sand on steel mesh sieve for 5 minutes; (3) immersion in lime solution at 10% (w/v), for 30 minutes; (4) fermentation in sugar solution at 10% (w/v), during 48 hours; and (5) natural pulp fermentation, during five days. The seeds were submitted to germination test at darkness and lightness, as well as, to length seedlings and emergence test. Regardless the aril removal method, the germination percentage was lower at lightness than darkness highlighting the natural pulp fermentation treatment, which presented 86% of seeds germinated. On the other hand, the aril removal methods did not affect the seedlings emergence, with emergence percentages ranged from 88 to 94%.


Resumo As espécies de maracujá apresentam grande importância econômica, tanto para o consumo in natura, quanto para a indústria. A principal maneira de propagar essas espécies é por sementes; contudo, a presença de arilo e condições ambientais pode inibir a germinação. Nesse sentido, objetivou-se estudar o efeito de métodos de remoção do arilo e luminosidade na qualidade e germinação das sementes de Passiflora edulis var. flavicarpa. Cinco métodos foram empregados para a remoção do arilo: (1) fricção em peneira de malha de aço por cinco minutos; (2) fricção com areia grossa em peneira de malha de aço por cinco minutos; (3) imersão em solução de cal a 10% (m/v), por 30 minutos; (4) fermentação da polpa em solução de açúcar a 10% (m/v), por 48 horas; e (5) fermentação natural da polpa, por cinco dias. As sementes foram submetidas ao teste de germinação no escuro e no claro, teste de comprimento de plântulas e teste de emergência. Independente do método de remoção do arilo, a porcentagem de germinação no claro apresentou-se menor em comparação ao escuro, com destaque para o tratamento de fermentação natural da polpa, o qual apresentou 86% de sementes germinadas. Por outro lado, os métodos de remoção do arilo não afetaram a emergência das plântulas, com porcentagem de emergência variando entre 88 a 94%.


Assuntos
Sementes/fisiologia , Germinação/fisiologia , Passiflora/fisiologia , Flores/fisiologia , Sementes/crescimento & desenvolvimento , Sementes/efeitos da radiação , Passiflora/crescimento & desenvolvimento , Passiflora/efeitos da radiação , Plântula/fisiologia , Luz
4.
Actual. osteol ; 15(1): 20-33, ene. abr. 2019. ilus., graf., tab.
Artigo em Inglês | LILACS | ID: biblio-1048986

RESUMO

Published evidence reports the existence of two routes for the transformation of 7-dehydrocholecalciferol into previtamin D3: a photochemical route with the participation of UVB photons and another route that occurs in the darkness. Several reports appears to support the presence of these two routes in some mammals, birds, nonvascular plants (e.g.: mosses), vascular plants (e.g.: angiosperms) and lichens. The reviewed evidence suggests that in the darkness, the synthesis of vitamin D3 follows the same scheme of the photochemical pathway, but at a reduced rate respect to the synthesis under UVB radiation. The process of vitamin D synthesis in the dark, then, may be taken as an insurance for survival, at least for mammals and birds. The low rate of the synthesis of vitamin D3 in the absence of light produce low concentrations of vitamin D3 metabolites in plasma. Long term survival under these circumstances might be possible through upregulation of vitamin D receptors (VDRs). In mole rats (South African rodents that live in the dark in underground tunnels), the reduced rate of vitamin D3 synthesis produce low levels of plasma vitamin D3 and their metabolites 25(OH) D3 and 1α,25OH2 D3 . The fact that Kd and ßmax of the complex 1α,25(OH)2 D3 -VDR from the intestinal mucosa, kidneys and the Harderian glands of the mole rat Heterocephalus glaber are significantly different in each one of these tissues, is interpreted as an indicator that the VDRs are, in each tissue, adapted to the maintenance of normal physiological functions. (AU)


Varios trabajos publicados han informado que existen dos mecanismos para la transformación de 7-dehidrocolecalciferol en previtamina D3 : uno iniciado con el auxilio de fotones UVB y un segundo que ocurre en la oscuridad, sin el auxilio de radiación ultravioleta. Una serie de publicaciones contienen información que apoya la presencia de estos dos mecanismos en mamíferos, pájaros, plantas no vasculares (musgos), vasculares (angiospermas) y líquenes. La evidencia revisada sugiere que, en la oscuridad, la síntesis de vitamina D3 sigue el mismo esquema que la ruta fotoquímica y generalmente ocurre a una tasa reducida respecto de la síntesis bajo irradiación ultravioleta. La operación de la síntesis de vitamina D3 en la oscuridad, por lo menos para mamíferos y pájaros, puede tomarse como un reaseguro de sobrevida. La reducida tasa de síntesis de vitamina D en ausencia de luz produce bajas concentraciones en plasma de los metabolitos de la vitamina. La sobrevida saludable en estas condiciones sería posible mediante upregulation de los receptores. En las ratas topo Heterocephalus glaber (roedores sudafricanos que viven en permanente oscuridad, en túneles subterráneos), la reducida tasa de síntesis de vitamina D3 es la causa de los bajos niveles plasmáticos de la vitamina y sus metabolitos: 25(OH)D3 y 1α,25OH2 D3 . El hecho de que el Kd y ßmax del complejo 1α,25(OH)2 D3 -Vitamina-D-Receptor del intestino, riñón y glándulas de Harder de Heterocephalus glaber sean significativamente diferentes entre sí indicaría que los receptores se han modificado para mantener funciones fisiológicas normales en cada tejido. (AU)


Assuntos
Animais , Vitamina D/síntese química , Vitamina D/análogos & derivados , Vitamina D/biossíntese , Vitamina D/metabolismo , Aves/fisiologia , Escuridão , Briófitas/química , Traqueófitas/química , Líquens/química , Mamíferos/fisiologia
5.
J. oral res. (Impresa) ; 7(2): 55-60, feb. 18, 2018. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1120423

RESUMO

Periodontal disease (PD) has been considered a probable risk factor for several systemic diseases. among them, PD is presumed to be one of the possible etiologies of chronic illness of the central nervous system. In this context, poor oral health and PD is associated with substance abuse in humans. however, if periodontal lesions can produce addiction is unknown. this paper aims to evaluate the possibility that chronic periodontal injury (CPL) can cause ethanol binge intake in drink-in-darkness (DID) protocol in rats. in CPL group (n=10) experimental damage was done to the periodontal tissue of the second maxillary molar, the control group (n=9) received sham injury. forty-three days after CPL the intake of ethanol was assessed using several concentrations in DID experiment. during the DID experiment, we observed significant differences between the binge-type consumption of ethanol at the lowest concentration of 10 percent (p=0.01). differences in consumption of 20 percent ethanol are observed during a few days (p=0.04), and there are no differences in consumption at 40 percent concentration of ethanol (p=0.2). it is concluded that chronic periodontal lesion leads to alcoholism in wistar rats.


Assuntos
Animais , Ratos , Doenças Periodontais/complicações , Alcoolismo/etiologia , Periodontite Crônica/complicações , Sistema Nervoso Central , Perda de Dente/etiologia , Ratos Wistar , Etanol/efeitos adversos
6.
Annals of Dermatology ; : 522-528, 2018.
Artigo em Inglês | WPRIM | ID: wpr-717773

RESUMO

Dark circles refer to visible darkness of the infra-orbital areas. Dark circles are a cosmetic concern for many individuals, although not a medical concern. Moreover, clear definitions and possible causes of dark circles have not been elucidated. This study reviews the possible causes and treatment options for dark circles based on a review of the medical literature and the authors' clinical experience. Potential factors that contribute to dark circles include excessive pigmentation, shadowing due to tear troughs and infra-orbital fat herniation, shadowing due to infraorbital laxity and wrinkles, and thin, translucent skin overlying the orbicularis oculi muscle. Given the different possible causes for dark circles, therapeutic modalities must be individualized for each patient. Because various factors cause dark circles, it is useful to identify the underlying causes in order to select the appropriate treatment.


Assuntos
Humanos , Escuridão , Pigmentação , Técnica Histológica de Sombreamento , Pele , Lágrimas
7.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467205

RESUMO

Abstract Passion fruits species presents a larger economic importance for in natura consumption and industry. The main way to propagate these species is by seeds; however, the aril presence and environmental conditions may inhibit the seeds germination. In this sense, the objective of this study was to evaluate the effect of aril removal methods and light conditions on P. edulis var. flavicarpa seeds quality and germination. There were used five methods to remove the seeds aril: (1) friction on steel mesh sieve for 5 minutes; (2) friction with coarse sand on steel mesh sieve for 5 minutes; (3) immersion in lime solution at 10% (w/v), for 30 minutes; (4) fermentation in sugar solution at 10% (w/v), during 48 hours; and (5) natural pulp fermentation, during five days. The seeds were submitted to germination test at darkness and lightness, as well as, to length seedlings and emergence test. Regardless the aril removal method, the germination percentage was lower at lightness than darkness highlighting the natural pulp fermentation treatment, which presented 86% of seeds germinated. On the other hand, the aril removal methods did not affect the seedlings emergence, with emergence percentages ranged from 88 to 94%.


Resumo As espécies de maracujá apresentam grande importância econômica, tanto para o consumo in natura, quanto para a indústria. A principal maneira de propagar essas espécies é por sementes; contudo, a presença de arilo e condições ambientais pode inibir a germinação. Nesse sentido, objetivou-se estudar o efeito de métodos de remoção do arilo e luminosidade na qualidade e germinação das sementes de Passiflora edulis var. flavicarpa. Cinco métodos foram empregados para a remoção do arilo: (1) fricção em peneira de malha de aço por cinco minutos; (2) fricção com areia grossa em peneira de malha de aço por cinco minutos; (3) imersão em solução de cal a 10% (m/v), por 30 minutos; (4) fermentação da polpa em solução de açúcar a 10% (m/v), por 48 horas; e (5) fermentação natural da polpa, por cinco dias. As sementes foram submetidas ao teste de germinação no escuro e no claro, teste de comprimento de plântulas e teste de emergência. Independente do método de remoção do arilo, a porcentagem de germinação no claro apresentou-se menor em comparação ao escuro, com destaque para o tratamento de fermentação natural da polpa, o qual apresentou 86% de sementes germinadas. Por outro lado, os métodos de remoção do arilo não afetaram a emergência das plântulas, com porcentagem de emergência variando entre 88 a 94%.

8.
Artigo em Inglês | IMSEAR | ID: sea-167158

RESUMO

The aim of this study was to optimize the in vitro preservation of yam genetic resources through reduction of the number of subcultures. Effects of different concentrations of activated charcoal (1 g.l-1, 2 g.l-1and 3 g.l-1) and temporary darkness were tested on the in vitro morphogenesis of three beninese yam accessions (Dcr28, Dcr164 and Da93G1). Galzy glutamine was used as basis culture medium and explants were microcuttings obtained from four months old plantlets. The results indicated that the activated charcoal, alone or combined with temporary darkness has an inhibitory effect on the aerial organs formation but favors root development with a greater mean number of root shoots (9.3±1.67 with 3 g.l-1 of activated charcoal) than the subtract without activated charcoal (2.5±0.17). A significant interaction was noted between accessions and concentration of activated charcoal indicating genotypic variability from the activated charcoal effect. The different accession plantlets growing in high concentration of activated charcoal culture media combined with temporary darkness were vigorous after eight month without subculture and subsequently allow doing one subculture per year.

9.
Archives of Aesthetic Plastic Surgery ; : 91-98, 2011.
Artigo em Coreano | WPRIM | ID: wpr-79012

RESUMO

Infraorbital dark circles refer to the darkness of lower eyelids and can be a significant cosmetic problem for the people of any age and sex. Although the general concern for dark circles is increasing, little has been published about the treatment of dark circles in the scientific literature. Dark circles are not a single disease but combination of causative symptoms. We classified patients to five groups according to patients' symptoms; bulging of infraorbital fat(Ia), sunken lower eyelids(Ib), depression or groove on midface(Ic), thin translucent skin(IIa), and excessive pigmentation(IIb). We reviewed medical records and photographs of patients retrospectively. The classification of patients and the treatment of the groups were evaluated. Problems of shape, especially bulging of infraorbital fat was the main cause of dark circles in most patients(65.2%). The treatment of each group included transconjunctival fat reposition or removal(Ia), single fat cell graft(Ib,IIa), microfat graft(Ic), and various dermatologic therapies(IIb). We obtained better results when we did combination of the treatments according to symptomatic groups.


Assuntos
Humanos , Adipócitos , Blefaroplastia , Cosméticos , Escuridão , Depressão , Pálpebras , Gorduras , Prontuários Médicos , Estudos Retrospectivos
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