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1.
J Med Virol ; 91(1): 22-30, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30133803

RESUMO

To analyze the effects of phenol red at various pH values on the Sabin type 2 inactivated polio vaccine (sIPV2), several biophysical techniques were used to evaluate the particle size and capsid protein for conformation. sIPV2's size was assessed via transmission electron microscopy and dynamic light scattering. The effects of various pH values (from 4.0 to 7.0) on the biophysical characters of sIPV2 particles in solution were determined by dynamic light scattering and zeta potential. The results clearly indicated that aggregation and instability occurred in the solution of sIPV2 particles at a pH of 6.0. Under similar conditions, by dynamic light scattering and zeta potential, the virus particles in solution showed more dispersion and were stable with the addition of 0.05 mM phenol red. According to circular dichroism and intrinsic tryptophan fluorescence data, it was observed that the secondary and tertiary structures of the sIPV2 particles were more stable with the protection of phenol red. At a pH below 6.0, the sIPV2 solution with phenol red had more D-antigen content, which was confirmed by enzyme-linked immunosorbent assay and rat experiments. These results strongly suggested that phenol red improved the pH stability of the sIPV2. The study indicated the potential of phenol red in preserving vaccine potency of the sIPV2 at various pH values.


Assuntos
Imunogenicidade da Vacina/efeitos dos fármacos , Fenolsulfonaftaleína/metabolismo , Vacina Antipólio de Vírus Inativado/imunologia , Poliovirus/efeitos dos fármacos , Vírion/efeitos dos fármacos , Animais , Fenômenos Biofísicos , Dicroísmo Circular , Estabilidade de Medicamentos , Difusão Dinâmica da Luz , Feminino , Concentração de Íons de Hidrogênio , Masculino , Microscopia Eletrônica , Vacina Antipólio de Vírus Inativado/química , Ratos Wistar
2.
J Med Virol ; 91(10): 1729-1736, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31187886

RESUMO

BACKGROUND: Polio eradication has been achieved in the world except for three countries due to the widespread use of the inactivated poliovirus vaccine (IPV) and the live-attenuated oral poliovirus vaccine. Following polio eradication, the IPV would be the only polio vaccine available. However, the mechanisms of the interactions between IPV and human antigen-presenting cells (APCs) remain largely unclear. METHODS: To investigate the involvement of the IPV in human monocytes, we downloaded the gene chip GSE44721 from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified using the GEO2R analysis tool. Functional and pathway enrichment analyses were performed for DEGs using the Metascape database. DEG-associated protein-protein-interactions (PPIs) were established by the Search Tool for the Retrieval of Interacting Genes website and visualized by Cytoscape. RESULTS: There were 240 DEGs (51 upregulated and 189 downregulated genes) identified from the GSE44721 data set, and they were significantly enriched in several biological processes, including antigen processing and presentation of lipid antigen via MHC class Ib, adaptive immune response, and response to interferon-gamma. One hundred thirty-six nodes were screened from the DEG PPI network. There were six significant hub proteins (WDR36, MRTO4, RPF2, PPAN, CD40, and BMS1) that regulated the IPV in human monocytes. CONCLUSIONS: In summary, using bioinformatical analysis, we have information for the immunization activated by the IPV in monocytes. Moreover, hormones and cytokines regulate the activation of APCs.


Assuntos
Células Apresentadoras de Antígenos/classificação , Células Apresentadoras de Antígenos/metabolismo , Poliomielite/prevenção & controle , Vacinas contra Poliovirus/imunologia , Biologia Computacional , Regulação para Baixo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/imunologia , Humanos , Monócitos/metabolismo , Poliomielite/genética , Poliovirus , Regulação para Cima , Vacinação
3.
RSC Adv ; 13(39): 27036-27045, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37693087

RESUMO

1,4-Cyclohexanedimethanol (CHDM) is a premium polyester monomer. In this paper, a series of Ru- Sn/γ-Al2O3 and Pd/γ-Al2O3 bimetallic composite catalysts were prepared by the impregnation method. The effects of preparation conditions such as active components, preparation methods, and the ratio of Sn to Ru on the reaction activity of the catalysts were studied. The bimetallic composite catalysts show desirable properties including high surface area and high dispersion of active centers. Pd-based catalysts were found to be effective in the initial stage of benzene ring hydrogenation, while Ru-based catalysts were found effective in the subsequent stage of carboxyl group hydrogenation. The Ru-Sn bimetallic active center was predominantly located in the Ru-based catalysts. In addition, the effects of reaction parameters such as reaction temperature, pressure, and time on hydrogenation reactions were also examined. It was found that increasing reaction temperature had no significant effect on the conversion rate of PTA, but it did affect the yield of CHDM, initially increasing and then decreasing. Increasing the reaction pressure resulted in a gradual increase in the yield of CHDM, while the conversion rate of PTA remained unchanged. The composite catalyst with a Sn/Ru ratio of 0.5 demonstrated the best performance, achieving a CHDM conversion of 96.3% and a yield of 72.2%.

4.
Steroids ; 199: 109310, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37714250

RESUMO

C21 steroidal glycosides are a group of natural compounds with biological activities such as anti-cancer, anti-microbial, and anti-viral properties. In this study, we isolated and determined the structure of a new C21 steroidal glycoside, named Marsdenialongise A from Marsdenia longipes W.T. Wang, using nuclear magnetic resonance spectroscopy and mass spectra data. Marsdenialongise A is a derivative of tenacigenin B and was isolated for the first time from a plant. The inhibitory effect of Marsdenialongise A on cancer cells was evaluated through MTT and cell migration assays, cell cycle, and apoptosis analyses. The results of the MTT assay showed that Marsdenialongise A reduces the cell viability of cancer cells, with the AGS cell line being more sensitive than other cell lines, with an IC50 value of 5.69 µM (for 48 h of treatment). Marsdenialongise A also exhibited an ability to prevent the migration of cancer cells in AGS cells. Further analysis using flow cytometry has revealed that Marsdenialongise A is capable of inducing cell cycle arrest and apoptosis. The overexpression of reactive oxygen species (ROS) production induced by Marsdenialongise A can be considered a cause that leads to the influence on the cell cycle and apoptosis of cancer cells. Thus, Marsdenialongise A can be considered a potential anti-cancer agent.

5.
Materials (Basel) ; 14(23)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34885596

RESUMO

Based on the actual hot zone structure of an AlN crystal growth resistance furnace, the global numerical simulation on the heat transfer process in the AlN crystal growth was performed. The influence of different heater structures on the growth of AlN crystals was investigated. It was found that the top heater can effectively reduce the axial temperature gradient, and the side heater 2 has a similar effect on the axial gradient, but the effect feedback is slightly weaker. The axial temperature gradient tends to increase when the bottom heater is added to the furnace, and the adjustable range of the axial temperature gradient of the side 1 heater + bottom heater mode is the largest. Our work will provide important reference values for AlN crystal growth by the resistance method.

6.
J Chem Phys ; 131(20): 204313, 2009 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-19947686

RESUMO

Oxygen-doped sodium cluster anions Na(n)O(2) (-) with n=41-148 have been studied by low temperature photoelectron spectroscopy and density functional theory (DFT), with a particular emphasis on those sizes where a spherical electron shell closing is expected. The experimental spectra are in good agreement with the electronic density of states of the DFT lowest energy structures. The cluster structures show segregation between an ionically bonded molecular unit located at the cluster surface and a metallic part. The DFT calculations reveal that each oxygen atom removes two electrons from the metallic electron gas in order to become an O(2-) dianion. A jellium model would therefore predict the electron shell closings to be shifted up by four sodium atoms with respect to pure Na(n) (-) cluster anions. The electron shell closings for Na(n)O(2) (-) are located at n=43, 61, 93, and 139, so the expected four-atom shift is observed only for the small clusters of up to n=61, while a two-atom shift is observed for the larger clusters. The DFT calculations explain this departure from jellium model predictions in terms of a structural transition in the ionically bonded molecular unit.

7.
Rev. bras. med. esporte ; Rev. bras. med. esporte;29: e2022_0219, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1387950

RESUMO

ABSTRACT Introduction There was a delay in China for the implementation of athletic physical training, often opting for technical and repetitive movements in their teaching method, resulting in an unsatisfactory didactic model. Objective Innovate physical training technology for teaching athletics in colleges and universities. Methods 80 students in two college and university athletics sports classes were submitted to two weekly athletics classes lasting 60 minutes. This paper measured and collected data before and after the battery of exercises, comparing the results pertinent to the group's physical fitness. All training lasted eight weeks. After this period, the relevant indices were measured again, ranked, and compared. Results The research shows that physical training can improve students' athletic performance in different grades, and the effect of athletic gain in students with lower initial performance is more significant. At the same time, strengthening physical training can effectively improve the basal performance of athletics and reduce the occurrence of sports injuries, ensuring the safety of the sports experienced. Conclusion Physical training can promote positive performance in athletics, deserving further research to popularize the implementation of athletic training in athletics for colleges and universities. Level of evidence II; Therapeutic studies - investigation of treatment results.


RESUMO Introdução Houve um atraso na China para a implementação do treino físico atlético, muitas vezes optando por movimentos técnicos e repetitivos em seu método de ensino, resultando num modelo didático insatisfatório. Objetivo Inovar a tecnologia de treinamento físico do ensino de atletismo em faculdades e universidades. Métodos 80 alunos em duas aulas de esportes de atletismo de Faculdades e universidades foram submetidos à duas aulas semanais de atletismo com duração de 60 minutos, este artigo mediu e coletou os dados antes e após a bateria de exercícios, comparando os resultados pertinentes à aptidão física do grupo. Todo o treinamento durou oito semanas. Após este período, os índices relevantes foram medidos novamente, classificados e comparados. Resultados A pesquisa mostra que o treinamento físico pode melhorar o desempenho atlético dos alunos em diferentes séries, e o efeito de ganho esportivo em alunos com menor desempenho inicial é mais significativo. Ao mesmo tempo, o fortalecimento do treinamento físico pode melhorar efetivamente o desempenho basal do atletismo e reduzir a ocorrência de lesões esportivas, garantindo a segurança dos esportes experenciados. Conclusão O treinamento físico pode promover rendimento positivo nos esportes de atletismo, merecendo mais pesquisas afim de popularizar a implementação do treinamento esportivo em atletismo para as Faculdades e universidades. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.


RESUMEN Introducción En China se ha producido un retraso en la implantación del entrenamiento físico atlético, optando a menudo por movimientos técnicos y repetitivos en su método de enseñanza, lo que ha dado lugar a un modelo didáctico insatisfactorio. Objetivo Innovar la tecnología de entrenamiento físico de la enseñanza del atletismo en colegios y universidades. Métodos 80 estudiantes de dos clases de deportes de atletismo de la universidad fueron sometidos a dos clases semanales de atletismo de 60 minutos de duración, este trabajo midió y recogió los datos antes y después de la batería de ejercicios, comparando los resultados pertinentes a la aptitud física del grupo. La formación completa duró ocho semanas. Tras este periodo, se volvieron a medir los índices pertinentes, se clasificaron y se compararon. Resultados La investigación muestra que el entrenamiento físico puede mejorar el rendimiento deportivo de los estudiantes en diferentes grados, y el efecto de la ganancia deportiva en los estudiantes con menor rendimiento inicial es más significativo. Al mismo tiempo, el fortalecimiento del entrenamiento físico puede mejorar eficazmente el rendimiento basal del atletismo y reducir la aparición de lesiones deportivas, garantizando la seguridad de los deportistas experimentados. Conclusión El entrenamiento físico puede promover un rendimiento positivo en los deportes de atletismo, mereciendo una mayor investigación con el fin de popularizar la implementación del entrenamiento en el atletismo para los colegios y universidades. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

8.
PLoS One ; 9(9): e106587, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25222483

RESUMO

EPR tooth in vivo dosimetry is an attractive approach for initial triage after unexpected nuclear events. An X-band cylindrical TM010 mode resonant cavity was developed for in vivo tooth dosimetry and used in EPR applications for the first time. The cavity had a trapezoidal measuring aperture at the exact position of the cavity's cylindrical wall where strong microwave magnetic field H1 concentrated and weak microwave electric field E1 distributed. Theoretical calculations and simulations were used to design and optimize the cavity parameters. The cavity features were evaluated by measuring DPPH sample, intact incisor samples embed in a gum model and the rhesus monkey teeth. The results showed that the cavity worked at designed frequency and had the ability to make EPR spectroscopy in relative high sensitivity. Sufficient modulation amplitude and microwave power could be applied into the aperture. Radiation induced EPR signal could be observed remarkably from 1 Gy irradiated intact incisor within only 30 seconds, which was among the best in scan time and detection limit. The in vivo spectroscopy was also realized by acquiring the radiation induced EPR signal from teeth of rhesus monkey whose teeth was irradiated by dose of 2 Gy. The results suggested that the cavity was sensitive to meet the demand to assess doses of significant level in short time. This cavity provided a very potential option for the development of X-band in vivo dosimetry.


Assuntos
Radiometria/métodos , Dente/efeitos da radiação , Animais , Carga Corporal (Radioterapia) , Macaca mulatta , Liberação Nociva de Radioativos , Radiometria/instrumentação , Sensibilidade e Especificidade , Razão Sinal-Ruído , Triagem
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