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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(8): 1136-1141, 2022 Aug 06.
Artigo em Chinês | MEDLINE | ID: mdl-35922244

RESUMO

Obesity has become a global public health problem that seriously threatens population health. The Chinese government has attached great importance to prevent and control the negative impacts of obesity on individuals, families and society. China has established a policy system for obesity, and made certain achievements in behavioral intervention, drug treatment, traditional Chinese medicine treatment, and surgical treatment. This study summarizes the prevention and treatment experience of obesity in China in order to provide reference for African countries to better formulate prevention and treatment strategies for obesity in line with their local context.


Assuntos
Obesidade , Saúde Pública , Povo Asiático , China/epidemiologia , Governo , Humanos , Obesidade/prevenção & controle
2.
Nature ; 586(7831): 693-696, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33116290

RESUMO

Fast radio bursts (FRBs) are millisecond-duration radio transients1,2 of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star magnetospheres3-5 or relativistic shocks far from the central energy source6-8. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters9,10 or variable polarization angles in some other apparently one-off events11,12. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks.

4.
Zhonghua Gan Zang Bing Za Zhi ; 27(1): 27-32, 2019 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-30685920

RESUMO

Objective: To investigate the molecular mechanism of poor response of nucleoside and interferon therapy in some patients with chronic hepatitis B (CHB) and the negative regulatory factor of suppressor of cytokine signaling 3 (SOCS3) expression in the interferon-signaling pathway. Also, study the clinical relationship between SOCS3 and antiviral efficacy of nucleoside and interferon. Methods: Peripheral blood and matched liver tissue samples from 54 CHB patients who participated in the OSST study were selected. HBsAg was measured at different time points (baseline and weeks 12, 24, 36, and 48) to observe the antiviral efficacy. Meanwhile, quantitative real-time PCR, and immunohistochemistry were used to detect the expression levels of SOCS3 mRNA in peripheral blood mononuclear cells (PBMCs) and matched liver tissues (baseline and 48 weeks). At the end of the 48-week treatment, patients with HBsAg negative or HBeAg seroconversion were defined as response group, and vice versa. Paired t-tests were used to compare normal distribution variables and the Mann-Whitney U test was used to compare the median differences between groups of non-normally distributed variables. Results: After 48 weeks of treatment, serum HBsAg levels in the Peg-IFN group continued to decline (average decrease of 1.14 log(10) IU / ml at week 48; P = 0.001 compared with baseline), while the entecavir group remained almost unchanged during treatment (average decrease was 0.05 log(10) IU / ml at week 48; compared with baseline P = 0.12). The expression of SOCS3 mRNA (Messenger RNA, mRNA) in peripheral blood and liver tissues of non-responder group was significantly higher than the response group in the course of Peg-IFNα2a treatment. The immunohistochemical results of liver tissue showed that the expression of SOCS3 in the non-responder group was significantly higher than that in the response group at baseline (P = 0.027). After 48 weeks of treatment with Peg-IFNα2a, the expression of SOCS3 in the non-responder group was significantly higher than that in the baseline and response groups (P = 0.003, P = 0.012, respectively). Conclusion: The expression of SOCS3 in peripheral blood mononuclear cells and liver tissues of non-responding CHB patients was significantly higher than that of responding CHB patients during interferon and nucleoside antiviral therapy. We speculated that SOCS3 might affect the antiviral efficacy through negative regulation of JAK-STAT signaling pathway, and partly expose the mechanism of interferon resistance.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Leucócitos Mononucleares , Nucleosídeos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Proteína 3 Supressora da Sinalização de Citocinas/genética , DNA Viral/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Humanos , Interferon-alfa/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Resultado do Tratamento
5.
Phys Rev E ; 98(1-1): 012902, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30110734

RESUMO

Soil-composing particles undergo wettability changes, impacting hydraulic and mechanical processes such as erosion and landslides. Such processes evolve at very small scales, typically at the particle level. Here we capture the evolution of liquid interfaces in a single particle and several particles with the lattice Boltzmann (LB) method. The paper presents a three-dimensional LB study on the droplet dynamics on a layer of uniformly packed spherical particles with varying size and intrinsic contact angle (CA) aimed at mimicking conditions comparable to those of real soils. The numerical droplet is initialized close to the granular surface and deposited by gravity. Three spreading and infiltration behaviors were identified: a droplet with a stable apparent CA, a droplet with a metastable apparent CA before infiltration, and immediate infiltration. The results showed that the formation of a droplet with a stable or metastable spherical-cap shape depends on the particle size and the intrinsic CA. Furthermore, the initial wetted zone expansion was found to be governed by inertial effects with its behavior characterized by a power law. Finally, the apparent CA, which is closely related to the intrinsic CA, was found to be influenced by the particle size due to a significant portion of the droplet being embedded into the granular surface for the larger particles and reducing the apparent CA. This paper provides a basis for future research targeting the behavior of droplet interaction with granular surfaces with variable intrinsic CAs (from wettable to superhydrophobic) such as soils and other granular materials for industrial applications. The numerical approach implemented can also be extended to model other dynamic processes for a droplet, such as evaporation, high-velocity impacting, and lateral sliding.

6.
Genet Mol Res ; 14(2): 3633-9, 2015 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-25966132

RESUMO

Herein, we investigated the clinical value of concurrent radiochemotherapy for patients with advanced cervical cancer and its effects on adverse clinical symptoms. Forty patients with cervical cancer were recruited from January 2011 to January 2014 for this study. Participants were randomly allocated into a test or control group, with 20 patients in each group. Patients in the test group were treated with concurrent radiochemotherapy, whereas patients in the control group received only traditional radiotherapy. At the end of the observation period, clinical efficacy in the two groups was compared. Patients were followed up for 2 years, and the rates of recurrence, survival, and complications were compared; ultrasonographic findings before and after radiotherapy were also correlated. Patients in the test group who received concurrent radiochemotherapy showed significantly higher clinical efficacy than the control group at the end of treatment cycles. After 2 years of follow-up, the rates of recurrence, mortality, and complications were all significantly lower in the test group than in the control group (P < 0.05). Comparison of ultrasonographic findings before and after radiochemotherapy showed that the size of the tumor was significantly smaller in patients after concurrent radiochemotherapy. Compared with traditional radiotherapy, concurrent radiochemotherapy significantly improved clinical outcomes in patients with advanced cervical cancer. Concurrent radiochemotherapy also enhanced the rate of survival and decreased the rate of relapse, with enhanced clinical safety and no significant side effects. Thus, concurrent radiochemotherapy can be more broadly applied in the treatment of advanced cervical cancer.


Assuntos
Quimiorradioterapia/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Adulto , Colo do Útero/efeitos dos fármacos , Colo do Útero/efeitos da radiação , Colo do Útero/ultraestrutura , Quimiorradioterapia/efeitos adversos , Cistite/etiologia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Radioterapia/efeitos adversos , Radioterapia/métodos , Resultado do Tratamento , Ultrassonografia , Neoplasias do Colo do Útero/radioterapia
7.
J Viral Hepat ; 17 Suppl 1: 24-33, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20586931

RESUMO

Telbivudine is an orally bioavailable L-nucleoside with potent and specific anti-hepatitis B virus activity. The higher rate of hepatitis B e antigen (HBeAg) seroconversion during telbivudine treatment than other potent anti-HBV agents suggests a potential immunomodulatory effect. We sought to determine the effects of telbivudine on the immune system, particularly on cytokine production and T-cell response, using an animal model with mouse hepatitis virus strain 3 (MHV-3)-induced hepatitis. The effects of telbivudine on virus replication and cytokine production were investigated in vitro using MHV-3-infected macrophages, and the effects on T-cell response were investigated in vivo in an MHV-3-induced viral hepatitis model. Telbivudine had no effect on MHV-3 replication in macrophages. However, the production of tumour necrosis factor-alpha and interleukin-12 was increased significantly in MHV-3-induced macrophages treated with telbivudine. In vivo survival was enhanced in telbivudine-treated mice, with marked normalization in clinical conditions and histological lesions. Serum levels of interferon-gamma were elevated significantly after telbivudine treatment in MHV-3-infected C3H mice. In contrast, serum interleukin-4 levels were decreased significantly. Furthermore, telbivudine treatment enhanced the ability of T cells to undergo proliferation and secrete cytokines but did not affect cytotoxicity of infected hepatocytes. Of note, we found that telbivudine treatment suppressed programmed death ligand 1 expression on T cells. The results demonstrate the immunomodulatory properties of telbivudine, independent of its antiviral activity, in a mouse model of MHV-3-induced hepatitis.


Assuntos
Antígeno B7-H1/análise , Citocinas/metabolismo , Hepatite Viral Animal/tratamento farmacológico , Hepatite Viral Animal/imunologia , Fatores Imunológicos/administração & dosagem , Nucleosídeos/administração & dosagem , Pirimidinonas/administração & dosagem , Células Th1/imunologia , Animais , Antivirais/administração & dosagem , Células Cultivadas , Feminino , Macrófagos/imunologia , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Vírus da Hepatite Murina/efeitos dos fármacos , Análise de Sobrevida , Telbivudina , Células Th1/química , Timidina/análogos & derivados
8.
J Asian Nat Prod Res ; 9(2): 115-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17454308

RESUMO

A novel macrocyclic spermine alkaloid incasine C' (1), along with a known compound incasine C (2), were isolated from the whole plants of Incarvillea sinensis, and their structures were elucidated on the basis of chemical and spectroscopic evidence.


Assuntos
Bignoniaceae/química , Espermina/análogos & derivados , Estrutura Molecular , Espermina/química , Espermina/isolamento & purificação
9.
Planta Med ; 67(2): 114-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11301854

RESUMO

Incarvillateine (1), a new monoterpene alkaloid carrying a characteristic cyclobutane ring, has been found to show significant antinociceptive activity in a formalin-induced pain model in mice. To investigate the correlation between its structure and antinociceptive activity, and especially to study whether a cyclobutane ring is necessary or not for expression of activity, we evaluated the antinociceptive activity of two constructive units of incarvillateine, such as a monoterpene unit (incarvilline, 3) and a phenylpropanoid unit (ferulic acid, 2) in the formalin test, and compared activity of the units with that of incarvillateine. Furthermore, in order to obtain more information about the structure-activity relationships, monoterpene alkaloid derivatives, such as incarvine C (5, a precursor of incarvillateine), incarvine A (4, an ester compound comprised of two monoterpene alkaloids and a monoterpene) and 3,3'-demethoxy-4,4'-dehydroxyincarvillateine (6, a synthetic new compound), were examined. The antinociceptive effect of 3,3'-demethoxy-4,4'-dehydroxyincarvillateine was equal to that of incarvillateine. Meanwhile, the other compounds exhibited no or weak activity. These results suggested that the cyclobutane moiety of incarvillateine plays an important role in expression of antinociceptive action.


Assuntos
Alcaloides/farmacologia , Analgésicos/farmacologia , Compostos Azabicíclicos/farmacologia , Ácidos Cumáricos/farmacologia , Monoterpenos , Plantas Medicinais/química , Terpenos/farmacologia , Alcaloides/isolamento & purificação , Analgésicos/isolamento & purificação , Animais , Compostos Azabicíclicos/isolamento & purificação , Ácidos Cumáricos/isolamento & purificação , Modelos Animais de Doenças , Formaldeído/toxicidade , Camundongos , Estrutura Molecular , Dor/induzido quimicamente , Relação Estrutura-Atividade , Terpenos/isolamento & purificação
10.
J Nat Prod ; 62(9): 1293-4, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10514316

RESUMO

Incarvillea sinensis is a wild plant distributed in northern China. The dried whole plant has been traditionally used to treat rheumatism and relieve pain as an ancient Chinese crude drug. To investigate its antinociceptive activity, we evaluated several fractions derived from the methanolic extract of Incarvillea sinensis in the formalin-induced pain model in mice. Incarvillateine, a novel monoterpene alkaloid, has been found to show significant antinociceptive activity. Here we report the antinociceptive activity of incarvillateine and compare its activity with that of morphine. Additionally, we suggest that its action may be related to influence on the central opioid pathways.


Assuntos
Alcaloides/farmacologia , Analgésicos não Narcóticos/farmacologia , Monoterpenos , Plantas Medicinais/química , Terpenos/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Analgésicos não Narcóticos/química , Analgésicos não Narcóticos/isolamento & purificação , Animais , Cristalografia por Raios X , Masculino , Medicina Tradicional Chinesa , Camundongos , Estrutura Molecular , Terpenos/química , Terpenos/isolamento & purificação
11.
Yao Xue Xue Bao ; 32(10): 765-8, 1997 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-11596220

RESUMO

One new flavonoide was isolated from Vicia amoena Fisch. On the basis of spectral (UV, MS, NMR) and chemical reactions, it was elucidated to be kaempferol-3-O-beta-D-mannoside, named amoenin(A3). Moreover, five known compounds have been isolated and identified as quercetin, kaempferol, quercetin-3-O-alpha-L-rhamoside, quercetin-3-O-beta-D-glucoside, kaempferol-3, 7-O-alpha-L-dirhamoside. The total flavonoides showed significant effects on inducing hyperlipidemia and increasing micro-blood vessel elasticity.


Assuntos
Medicamentos de Ervas Chinesas/química , Fabaceae/química , Flavonoides/isolamento & purificação , Quempferóis , Manosídeos/isolamento & purificação , Quercetina/análogos & derivados , Flavonoides/química , Manosídeos/química , Estrutura Molecular , Quercetina/química , Quercetina/isolamento & purificação
12.
Appl Environ Microbiol ; 60(7): 2653-6, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16349341

RESUMO

Two arsenic-resistant plasmids were constructed and introduced into Thiobacillus ferrooxidans strains by conjugation. The plasmids with the replicon of wide-host-range plasmid RSF1010 were stable in T. ferrooxidans. The arsenic resistance genes originating from the heterotroph were expressed in this obligately autotrophic bacterium, but the promoter derived from T. ferrooxidans showed no special function in its original host.

13.
J Bacteriol ; 176(10): 2892-7, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8188590

RESUMO

The broad-host-range IncP plasmids RP4, R68.45, RP1::Tn501, and pUB307 were transferred to acidophilic, obligately chemolithotrophic Thiobacillus ferrooxidans from Escherichia coli by conjugation. A genetic marker of kanamycin resistance was expressed in T. ferrooxidans. Plasmid RP4 was transferred back to E. coli from T. ferrooxidans. The broad-host-range IncQ vector pJRD215 was mobilized to T. ferrooxidans with the aid of plasmid RP4 integrated in the chromosome of E. coli SM10. pJRD215 was stable, and all genetic markers (kanamycin/neomycin and streptomycin resistance) were expressed in T. ferrooxidans. By the use of suicide vector pSUP1011, transposon Tn5 was introduced into T. ferrooxidans. The influence of some factors on plasmid transfer from E. coli to T. ferrooxidans was investigated. Results showed that the physiological state of donor cells might be important to the mobilization of plasmids. The transfer of plasmids from E. coli to T. ferrooxidans occurred in the absence of energy sources for both donor and recipient.


Assuntos
Elementos de DNA Transponíveis/genética , Escherichia coli/genética , Técnicas de Transferência de Genes , Plasmídeos/genética , Thiobacillus/genética , Conjugação Genética , Marcadores Genéticos , Resistência a Canamicina/genética
14.
Zhongguo Zhong Yao Za Zhi ; 18(11): 677-9, 703, 1993 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-8003229

RESUMO

Five flavonoids were isolated from the aerial parts of Epimedium acuminatum. Their structures were determined chemically and spectroscopically to be baohuoside VI, tricin, icaritin, icariside I and baohuoside I.


Assuntos
Medicamentos de Ervas Chinesas/química , Flavonoides/isolamento & purificação
15.
Yao Xue Xue Bao ; 27(2): 113-6, 1992.
Artigo em Chinês | MEDLINE | ID: mdl-1414364

RESUMO

Siphonostegia chinensis Benth. as a traditional Chinese medicine "liujinu" has been used for centuries in China, but up to date little has been reported about its chemistry. Now, four compounds have been isolated from the aerial parts of this genus. On the basis of spectroscopic analysis (UV, IR, MS, 1HNMR, 13CNMR and 2D-NMR) and chemical evidences, compound I was shown to be a new pyridinemonoterpene alkaloid which is a stereoisomer of the known compound cantleyine, and named isocantleyine. Its structure was determined as 5H-2-pyridine-4-carboxylic acid, 6,7-dihydro-6-hydroxy-7-methyl-methyl ester. Compound III was identified as the known compound loliolide. The other two (II and IV) are still under investigation. This paper deals mainly with the structure identification of compound I.


Assuntos
Medicamentos de Ervas Chinesas/química , Ácidos Isonicotínicos , Piridinas/isolamento & purificação , Terpenos/isolamento & purificação , Piridinas/química , Terpenos/química
16.
Appl Environ Microbiol ; 58(1): 429-30, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16348639

RESUMO

The broad-host-range IncP plasmids RP4, R68.45, RP1::Tn501, and and pUB307 were transferred directly to extremely acidophilic Thiobacillus thiooxidans from Escherichia coli by conjugation at frequencies of 10 to 10 per recipient. The ability of T. thiooxidans to receive and express the antibiotic resistance markers was examined. The plasmid RP4 was transferred back to E. coli from T. thiooxidans at a frequency of 1.0 x 10 per recipient.

17.
Zhongguo Zhong Yao Za Zhi ; 14(5): 296-8, 319, 1989 May.
Artigo em Chinês | MEDLINE | ID: mdl-2512948

RESUMO

Six alkaloids were isolated from Radix Sophorae Tonkinensis. On the basis of spectrometric analysis and physico-chemical constants they were identified as (I) (+)-matrine, (II) (-)-cytisine, (III) (+)-matrine N-oxide, (IV)(+)-sophocarpine N-oxide, (V)(+)-sophoramine and (VI) (+)-sophoranol respectively. (II), (IV), (V) and (VI) were isolated for the first time from Radix Sophorae Tonkinensis.


Assuntos
Alcaloides/análise , Medicamentos de Ervas Chinesas/análise , Fabaceae , Plantas Medicinais , Azocinas , Quinolizinas , Estereoisomerismo
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