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1.
J Ethnopharmacol ; 287: 114940, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-34968665

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sanren decoction (SRD) is a well-known traditional Chinese medicine prescription containing eight kinds of materials. SRD has been used mainly in China for more than 200 years for the treatment of respiratory disorders that co-occur with a bad fever after midday. AIM OF THE STUDY: To evaluate the acute and 28-day subacute toxicity of an aqueous extract of SRD using in vivo methods. MATERIALS AND METHODS: To determine acute toxicity, SRD was administered by gavage at a dosage of 58.5 g/kg/day to male and female mice for 7 days. To determine subacute toxicity, SRD was administered at 3.3, 6.5, or 13 g/kg/day to male and female rats for 28 days. The general behavior, body weight, biochemical and hematological parameters, organ coefficients and pathological morphology of the treated animals were analyzed. RESULTS: Neither acute nor subacute concentrations of SRD caused significant changes in the body weights, general behavior, hematology and biochemical parameters, organ weights, or histopathological appearances of the liver, kidney, spleen, brain, lung or heart in mice or rats. CONCLUSIONS: The administration of SRD can be considered safe within the conditions of this study.


Assuntos
Peso Corporal/efeitos dos fármacos , Medicamentos de Ervas Chinesas/toxicidade , Tamanho do Órgão/efeitos dos fármacos , Animais , Animais não Endogâmicos , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
2.
J Biol Phys ; 48(1): 79-92, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34799817

RESUMO

In this work, a series of numerical simulations have been performed to obtain the steady shapes of red blood cells under a shear force field in the capillary. Two possible classes of steady shapes, the axisymmetric parachute and the non-axisymmetric parachute, are found. If we assume that oxygen diffusion across the red cell membrane is mediated by membrane curvature, it is found that the non-axisymmetric parachute will be more favorable due to its special shape which enables it to have a larger portion of membrane patch capable of releasing oxygen to tissues.


Assuntos
Eritrócitos , Oxigênio , Capilares , Membrana Eritrocítica
3.
Toxicol Res (Camb) ; 10(2): 183-191, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33884169

RESUMO

Qing Hao Gan Cao (QHGC), a Chinese medicinal formula containing Artemisia annua and Glycyrrhizae Radix et Rhizoma, has been used to treat sunstroke and as an antiviral agent for more than 800 years. It has not previously been subject to a toxicological safety evaluation in acute and subacute (28 days) studies. Therefore, the acute and subacute toxicity of an aqueous extract of QHGC were evaluated in vivo. For the QHGC preparation, the botanical raw materials were crushed into pieces and mixed in the ratio of 10:1 in distilled water for 12 h, then boiling three times for 2 h each time. The three decoctions were mixed and filtered, then spray-dried with hot air at 160°C for 30 min, and stored at room temperature. For the acute toxicity test, 72.0 g/kg of QHGC extract was administered by gavage to male and female mice. Body weight, general observations, and autopsy results were recorded. No mortality or toxicity signs were observed during the studies. For the subacute toxicity test, 4.0, 8.0, or 16.0 g/kg/day of QHGC extract was administered to rats for 28 days. General observations and mortality, body weight, biochemical and hematological parameters, organ weight, and pathological morphology were analyzed. The acute and subacute toxicity studies did not show significant changes in body weight, general observations, hematology and biochemical parameters, organ weight, and liver, spleen, stomach, duodenum, testis, ovary, lung, heart, and kidney histopathological analyses. The consumption of QHGC aqueous extract can be considered safe within the conditions of this study.

4.
J Ethnopharmacol ; 248: 112324, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31644940

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bei Qi Wu Jia (BQWJ), a modern preparation of a traditional Chinese medicinal formula, is a combination of Radix Astragali and Acanthopanacis Senticosi. Although BQWJ has been used to treat insomnia, fatigue, and loss of appetite, toxicological safety studies are rare in the literature. AIM OF THE STUDY: To evaluate the acute and subacute toxicity of BQWJ extract after oral administration in mice and rats, respectively. MATERIALS AND METHODS: In the acute toxicity study, mice underwent oral administration of 67.5 g extract/kg/day. In the subacute toxicity study, rats underwent a single oral administration of 1.25, 2.5, 5.0, or 10.0 g/kg/day of BQWJ extract for 28 days. The animals' general behavior, body weight, food intake, biochemical and hematologic parameters, organ coefficients, and pathological morphology were analyzed. RESULTS: No evidence of toxicity was observed in the mice after acute exposure to BQWJ extract. The subacute results included no deaths and no changes in general behavior. Although BQWJ extract resulted in some significant changes in other parameters, these alterations cannot be considered treatment-related because they remained within normal ranges throughout the 28 days. CONCLUSIONS: In conclusion, the oral administration of BQWJ extract at doses of less than 67.5 g/kg/day for 1 day or 10.0 g/kg/day for 28 consecutive days can be considered safe and showed no distinct toxicity or side effects in this study.


Assuntos
Medicamentos de Ervas Chinesas/toxicidade , Administração Oral , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Masculino , Camundongos , Nível de Efeito Adverso não Observado , Ratos Sprague-Dawley , Medição de Risco , Fatores de Tempo , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
5.
Phys Chem Chem Phys ; 18(9): 6893-900, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26879071

RESUMO

Electrochemical cycling stabilities were compared for undoped and Al/Co dual-doped spinel LiMn2O4 synthesized by solid state reactions. We observed the suppression of particle fracture in Al/Co dual-doped LiMn2O4 during charge/discharge cycling and its distinguishable particle morphology with respect to the undoped material. Systematic first-principles calculations were performed on undoped, Al or Co single-doped, and Al/Co dual-doped LiMn2O4 to investigate their structural differences at the atomistic level. We reveal that while Jahn-Teller distortion associated with the Mn(3+)O6 octahedron is the origin of the lattice strain, the networking -i.e. the distribution of mixed valence Mn ions - is much more important to release the lattice strain, and thus to alleviating particle cracking. The calculations showed that the lattice mismatching between Li(+) intercalation and deintercalation of LiMn2O4 can be significantly reduced by dual-doping, and therefore also the volumetric shrinkage during delithiation. This may account for the near disappearance of cracks on the surface of Al/Co-LiMn2O4 after 350 cycles, while some obvious cracks have developed in undoped LiMn2O4 at similar particle size even after 50 cycles. Correspondingly, Al/Co dual-doped LiMn2O4 showed a good cycling stability with a capacity retention of 84.1% after 350 cycles at a rate of 1C, 8% higher than the undoped phase.

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