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1.
Chinese Journal of School Health ; (12): 157-161, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1012459

RESUMO

Abstract@#To help children and adolescents grow up healthily, using literature, comparative analysis and other research methods, the historical development of Japan s physical fitness assessment system for children and adolescents are analyzed for the content structure of the latest version of its physical fitness assessment system (Sports adaptability assessment Ⅱ). On the basis of this analysis, some practical suggestions are proposed for improving the National Physical Fitness Standards for Students in China, such as adding a physical fitness assessment system for preschoolers, grouping the test subjects by age and setting common test indicators for males and females. Thus, the improved National Student Physical Fitness Standard is more aligned with the physical and mental growth patterns of Chinese children and adolescents.

2.
Environ Res ; 220: 115211, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36603657

RESUMO

The Pacific Ocean plays an important role in regulating the budget of climatically active gases and the burden of sulfate aerosols. Here, a field investigation was conducted to clarify the key processes and factors controlling climatically active gases, including dimethyl sulfide (DMS), carbonyl sulfide (OCS), carbon disulfide (CS2), and carbon dioxide (CO2), in both surface seawater and the lower atmosphere of the western Pacific. In addition, the relative contributions of different sources to atmospheric sulfate aerosols were quantitatively estimated, and their causes were explored. The maximum concentrations of DMS, OCS and CS2 and the minimum partial pressure of CO2 (pCO2) were observed in the Kuroshio-Oyashio Extension. Kuroshio-induced mesoscale eddies brought abundant nutrients and organic matter from the subsurface layer of Oyashio into the euphotic layer, thus enhancing primary productivity and accelerating the photoreaction of organic matter. These processes led to higher concentrations of DMS, OCS and CS2 and lower pCO2. However, the oligotrophic subsurface layer in the subtropical gyre and the strong barrier layer in the equatorial waters suppressed the upward fluxes of nutrients and organic matter, resulting in lower surface concentrations of DMS, OCS, and CS2 in these areas. Being far from the continents, atmospheric concentrations of DMS, OCS and CS2 and pCO2 in the western Pacific generally were observed to depend on the local sea-to-air exchange and may be regulated by atmospheric oxidation and mixing of air masses. In general, oceanic DMS emissions played an important role in the formation of sulfate aerosols in the western Pacific (accounting for ∼19.5% of total sulfate aerosols), especially in the Kuroshio-Oyashio Extension (∼32.3%). These processes in seawater may also determine the variations and emissions of other climatically active gases from biogenic and photochemical sources.


Assuntos
Dióxido de Carbono , Gases , Sulfatos , Oceano Pacífico , Aerossóis
4.
Curr Zool ; 66(2): 113-122, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32211037

RESUMO

In the face of ongoing habitat fragmentation, many primate species have experienced reduced gene flow resulting in a reduction of genetic diversity, population bottlenecks, and inbreeding depression, including golden snub-nosed monkeys Rhinopithecus roxellana. Golden snub-nosed monkeys live in a multilevel society composed of several 1 male harem units that aggregate to form a cohesive breeding band, which is followed by one or more bachelor groups composed of juvenile, subadult, and adult male members. In this research, we examine the continuous landscape resistance surface, the genetic diversity and patterns of gene flow among 4 isolated breeding bands and 1 all-male band in the Qinling Mountains, China. Landscape surface modeling suggested that human activities and ecological factors severely limit the movement of individuals among breeding bands. Although these conditions are expected to result in reduced gene flow, reduced genetic diversity, and an increased opportunity for a genetic bottleneck, based on population genetic analyses of 13 microsatellite loci from 188 individuals inhabiting 4 isolated breeding bands and 1 all-male band, we found high levels of genetic diversity but low levels of genetic divergence, as well as high rates of gene flow between males residing in the all-male band and each of the 4 breeding bands. Our results indicate that the movement of bachelor males across the landscape, along with their association with several different breeding bands, appears to provide a mechanism for promoting gene flows and maintaining genetic diversity that may counteract the otherwise isolating effects of habitat fragmentation.

5.
Am J Bot ; 102(2): 239-47, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25667077

RESUMO

PREMISE OF THE STUDY: Comparative phylogeography of intercontinental disjunct taxa allowed us not only to elucidate their diversification and evolution following geographic isolation, but also to understand the effect of climatic and geological histories on the evolutionary processes of closely related species. A phylogeographic analysis was conducted on the eastern Asian-North American disjunct genus Zizania to compare intracontinental phylogeographic patterns between different continents. METHODS: Surveys were conducted of 514 individuals using three chloroplast DNA fragments and three nuclear microsatellite loci. These individuals included 246 from 45 populations of Zizania latifolia in eastern Asia, and the following from North America: 154 individuals from 26 populations of Z. aquatica, 84 individuals from 14 populations of Z. palustris, and 30 individuals from one population of Z. texana. KEY RESULTS: The genetic diversity of North American Zizania was significantly higher than that of eastern Asian Zizania. High levels of genetic differentiation among populations and no signal of population expansion were detected in three widespread species. No phylogeographic structure was observed in Z. latifolia, and discordant patterns of cpDNA and microsatellite markers were observed in North American Zizania. CONCLUSIONS: Reduced variation in Zizania latifolia likely reflects its perennial life history, the North American origin of Zizania, and the relative homogeneity of aquatic environments. High levels of genetic differentiation suggest limited dispersal among populations in all Zizania species. The more complex patterns of diversification and evolution in North American Zizania may be driven by the greater impact of glaciation in North America relative to eastern Asia.


Assuntos
DNA de Plantas/análise , Evolução Molecular , Variação Genética , Oryza/genética , Filogenia , Filogeografia , Poaceae/genética , DNA de Cloroplastos/análise , Ásia Oriental , Geografia , Repetições de Microssatélites , América do Norte , Análise de Sequência de DNA , Especificidade da Espécie
6.
J Nat Prod ; 75(1): 82-7, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-22165973

RESUMO

Two novel 2-arylbenzofuran dimers, morusyunnansins A and B (1 and 2), two new biflavonoids, morusyunnansins C and D (3 and 4), two new flavans, morusyunnansins E and F (5 and 6), and four known flavans (7-10) were isolated from the leaves of Morus yunnanensis. Compounds 5-8 showed potent inhibitory effects on mushroom tyrosinase with IC(50) values ranging from 0.12 ± 0.02 to 1.43 ± 0.43 µM.


Assuntos
Benzofuranos/isolamento & purificação , Biflavonoides/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Flavonoides/isolamento & purificação , Monofenol Mono-Oxigenase/antagonistas & inibidores , Morus/química , Agaricales/enzimologia , Benzofuranos/química , Benzofuranos/farmacologia , Biflavonoides/química , Biflavonoides/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Relação Estrutura-Atividade
7.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2779, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22058819

RESUMO

In the title compound, C(17)H(21)N(3)O(4)S(2), an intra-molecular N-H⋯O hydrogen bond involving the proximate amine and nitro groups is observed. In the crystal, inter-molecular N-H⋯O hydrogen bonds involving the amine and SO(2) groups occur. One of the notro O atoms is disordered over two conformations with occupancies of 0.578 (12) and 0.422 (12).

8.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 7): o1835, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21837202

RESUMO

In the title compound, C(15)H(13)NO(4), the conjugated double-bond system between the two rings adopts a cis configuration and there is an intra-molecular indole-ketone C-H⋯O inter-action. The indole N-H group forms an inter-molecular hydrogen bond with a ketone O-atom acceptor, giving a chain structure along the ab direction. The O-heterocyclic ring adopts a boat conformation and makes a dihedral angle of 16.72 (6)° with the indole ring system.

9.
Bioorg Med Chem Lett ; 21(15): 4441-6, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21737271

RESUMO

Five new isoprenylated flavonoids, notabilisins A-E (1-5), and two known Diels-Alder adducts (6 and 7), were isolated from the twigs of Morus notabilis. Compounds 4 and 5 possess two novel pyran rings, which may be biogenetically derived from 3. Compounds 1 and 3 significantly promoted adipogenesis, characterized by increased lipid droplet and triglyceride content in 3T3L1 cells, and induced up-regulation of the expression of adipocyte-specific genes, aP2 and GLUT4.


Assuntos
Adipogenia/efeitos dos fármacos , Flavonoides/química , Morus/química , Animais , Linhagem Celular , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Conformação Molecular , Prenilação
10.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 5): o1216, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754514

RESUMO

The crystal of the title compound, C(13)H(12)N(2)O(6), contains a bifurcated intra-molecular hydrogen bond between the N-H group and one of the O atoms from both the nitro group and the dioxane-4,6-dione moiety. In addition, mol-ecules are linked by a series of inter-molecular C-H⋯O secondary inter-actions. The dihedral angles between the benzene ring and the nitro group and the conjugated part of the dioxane-4,6-dione moiety are 19.1 (2) and 17.89 (7)°, respectively.

11.
J Nat Prod ; 74(4): 816-24, 2011 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-21401118

RESUMO

Ten new isoprenylated flavonoids, nigrasins A-J (1-10), and three known compounds were isolated from the twigs of Morus nigra. Compounds 8 and 9 promoted adipogenesis, characterized by increased lipid droplet and triglyceride content in 3T3L1 cells, and induced up-regulation of the expression of adipocyte-specific genes, aP2 and GLUT4.


Assuntos
Adipogenia/efeitos dos fármacos , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Morus/química , Células 3T3-L1/efeitos dos fármacos , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Sequência de Bases , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Transportador de Glucose Tipo 4/efeitos dos fármacos , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Caules de Planta/química , Prenilação
12.
Beijing Da Xue Xue Bao Yi Xue Ban ; 41(4): 447-51, 2009 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-19727236

RESUMO

OBJECTIVE: To develop lipiodol-containing calcium alginate microspheres (LAMs) for embolization, and study the characterization for emoblization and the radiopacity. METHODS: LAMs were prepared by dripping method. The preparation of LAMs was optimized by orthogonal experiment which involved effects of three factors (the volume ratio of lipiodol to the external aqueous solution, airflow rate, and the weight pushing the injector) at three levels on the responses to the size, polydisperse index and entrapment efficiency of LAMs. The morphology of LAMs was observed under microscope. The elasticity of LAMs was investigated by texture analyzer. The capability injected through catheter of LAMs was monitored by video spinning-drop tensionmeter. The radiopacity of LAMs was measured by X-ray imaging system after LAMs were injected into vas of a rat. RESULTS: The optimal condition for preparation of LAMs was: the volume ratio of lipiodol to the external aqueous solution was 3:10, airflow rate was 40 g/mL and the weight pushing the injector was 100 g. According to the optimized condition, LAMs were prepared and characterized. The mean diameter of LAMs was (493.9 +/- 42.6) microm, the polydisperse index was 1.02 and the entrapment efficiency was (88.97 +/- 1.09) %. The LAMs were with round shape and smooth surface in view of photograph of microscope. The maximum average load was (1.09 +/- 0.18) N when LAMs were compressed to 60%. The LAMs were injected through catheter without much difficulty. The radiopacity of LAMs in rats was demonstrated to be visible under X-ray photography system. CONCLUSION: The radiopaque LAMs developed are suitable for the arterial embolization, with round shape, proper size, good elasticity, easy handling character and visible property under X-ray imaging. The radiopaque embolic agent is supposed to be useful for emoblization therapy.


Assuntos
Alginatos/química , Embolização Terapêutica/métodos , Óleo Etiodado/química , Microesferas , Radiografia Intervencionista/métodos , Animais , Meios de Contraste , Elasticidade , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Teste de Materiais , Tamanho da Partícula , Intensificação de Imagem Radiográfica/métodos , Ratos , Ratos Sprague-Dawley
13.
Fundam Clin Pharmacol ; 22(4): 429-37, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18705753

RESUMO

The multi-drug resistance (MDR) could be caused by the over-expression of adenosine triphosphate binding cassette transporters such as p-glycoprotein, thereby resulting in the efflux of anti-cancer drugs from the cells. An anti-resistant stealthy liposomal vincristine plus quinacrine was defined in this study. Human chronic myelogenous leukemia K562 and MDR K562 cells were included for comparisons. Anti-tumor activity studies were performed on female BALB/c nude mice with MDR K562 cell xenografts. Results showed that quinacrine was effective in reversing the resistance in the MDR K562 cells, and enhanced the anti-tumor effect of vincristine in K562 cells. The caspase-9 and -3 activities in the MDR K562 and K562 cells were increased with the dose rise of quinacrine. In the MDR K562 cell xenografts in mice, the anti-resistant tumor effect of the stealthy liposomal vincristine plus quinacrine was evidently observed. The enhanced anti-tumor effects of vincristine by quinacrine in the resistant/non-resistant K562 cells could be because of the direct injury and the potentiating apoptotic effect of vincristine via activating the initiator caspase-9 and subsequently the effector caspase-3, and the long circulatory effect of stealthy liposomes. The stealthy liposomal encapsulation of vincristine plus quinacrine could be a potential therapeutic approach for resistant human leukemia.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Experimental/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Humanos , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Quinacrina/administração & dosagem , Transplante Heterólogo , Células Tumorais Cultivadas , Vincristina/administração & dosagem
14.
J Control Release ; 129(1): 18-25, 2008 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-18466993

RESUMO

The cancer stem cells play a critical role in both initiation and relapse of the cancers as they are resistant to the most of cytotoxic agents and able to proliferate indefinitely. Vinorelbine stealthy liposomes and parthenolide stealthy liposomes were developed for providing beneficial pharmacological properties and to eradicate cancer stem cells and non-stem cancer cells together by a combination therapy. Cytotoxicity and cancer stem-like cells (side population, SP) identification were performed on human breast cancer cell lines MCF-7 and MDA-MB-231. SP cells were further sorted from MCF-7 cells and characterized. Inhibitory effect was evaluated on the sorted SP and non-SP cells. Antitumor activity was evaluated on MCF-7 xenografts in nude mice. SP cells were identified with a higher percentage in MCF-7 cells (3.8%) and lower in MDA-MB-231 cells (0.6%). Both vinorelbine and parthenolide inhibited the proliferation in MCF-7 and MDA-MB-231 cells. As compared to non-SP cells, inhibitory effect of vinorelbine in the SP cells was lower while a robust inhibitory effect was observed when applying vinorelbine in combination with parthenolide. In the MCF-7 xenografts, stealthy liposomal vinorelbine plus stealthy liposomal parthenolide produced a full inhibitory effect. This combination therapy may provide a potential strategy for eradication of breast cancer by targeting cancer together with cancer stem cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Lipídeos/química , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/química , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Relação Dose-Resposta a Droga , Composição de Medicamentos , Feminino , Humanos , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/patologia , Sesquiterpenos/administração & dosagem , Tecnologia Farmacêutica/métodos , Fatores de Tempo , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , Vinorelbina , Ensaios Antitumorais Modelo de Xenoenxerto
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