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1.
Artigo em Inglês | MEDLINE | ID: mdl-35627408

RESUMO

BACKGROUND: Many epidemiological studies have recently assessed respiratory mortality attributable to ambient temperatures. However, the associations between temperature change between neighboring days and years of life lost are insufficiently studied. Therefore, we assessed the attributable risk of temperature change between neighboring days on life loss due to respiratory disease. METHODS: We obtained daily mortality and weather data and calculated crude rates of years of life lost for 70 counties in Hunan Province, Central China, from 2013 to 2017. A time-series design with distributed lag nonlinear model and multivariate meta-regression was used to pool the relationships between temperature change between neighboring days and rates of years of life lost. Then, we calculated the temperature change between neighboring days related to average life loss per death from respiratory disease. RESULTS: The total respiratory disease death was 173,252 during the study period. The association between temperature change and years of life lost rates showed a w-shape. The life loss per death attributable to temperature change between neighboring days was 2.29 (95% CI: 0.46-4.11) years, out of which 1.16 (95% CI: 0.31-2.01) years were attributable to moderately high-temperature change between neighboring days, and 0.99 (95% CI: 0.19-1.79) years were attributable to moderately low-temperature change between neighboring days. The temperature change between neighboring days related to life loss per respiratory disease death for females (2.58 years, 95% CI: 0.22-4.93) and the younger group (2.97 years, 95% CI: -1.51-7.44) was higher than that for males (2.21 years, 95% CI: 0.26-4.16) and the elderly group (1.96 years, 95% CI: 0.85-3.08). An average of 1.79 (95% CI: 0.18-3.41) life loss per respiratory disease death was related to non-optimal ambient temperature. CONCLUSIONS: The results indicated that more attention should be given to temperature change, and more public health policies should be implemented to protect public health.


Assuntos
Transtornos Respiratórios , Doenças Respiratórias , Idoso , China/epidemiologia , Temperatura Baixa , Feminino , Humanos , Masculino , Doenças Respiratórias/epidemiologia , Temperatura
2.
Artigo em Inglês | MEDLINE | ID: mdl-35047050

RESUMO

Chronic obstructive pulmonary disease (COPD) is a common chronic pulmonary disease with multiple etiologies and pathological changes. PYK2 expression is significantly increased in lipopolysaccharide-induced lung injury, but it mediates chronic lung inflammation. The mechanism of its occurrence remains unclear. Quanzhenyiqitang is often used in clinical treatment of COPD, so this study explored the mechanism of its treatment of lipopolysaccharide-induced lung injury. In this study, transfection, flow cytometry, QRT-PCR, and Western blotting methods were used to study the mechanism of Quanzhenyiqitang lipopolysaccharide-induced lung injury. The results showed that the mechanism of occurrence remains unclear. Our novel observations imply that the PYK2/p38MAPK/HDAC2/CK2 pathway is one of the fundamental underlying mechanisms that mediate the pathogenic progression of COPD, and Quanzhenyiqitang may be the therapeutic drug to prevent chronic inflammation and delay the progression of COPD by inhibiting PYK2 signaling pathways.

3.
PLoS Genet ; 13(5): e1006770, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28489859

RESUMO

Isoflavones comprise a group of secondary metabolites produced almost exclusively by plants in the legume family, including soybean [Glycine max (L.) Merr.]. They play vital roles in plant defense and have many beneficial effects on human health. Isoflavone content is a complex quantitative trait controlled by multiple genes, and the genetic mechanisms underlying isoflavone biosynthesis remain largely unknown. Via a genome-wide association study (GWAS), we identified 28 single nucleotide polymorphisms (SNPs) that are significantly associated with isoflavone concentrations in soybean. One of these 28 SNPs was located in the 5'-untranslated region (5'-UTR) of an R2R3-type MYB transcription factor, GmMYB29, and this gene was thus selected as a candidate gene for further analyses. A subcellular localization study confirmed that GmMYB29 was located in the nucleus. Transient reporter gene assays demonstrated that GmMYB29 activated the IFS2 (isoflavone synthase 2) and CHS8 (chalcone synthase 8) gene promoters. Overexpression and RNAi-mediated silencing of GmMYB29 in soybean hairy roots resulted in increased and decreased isoflavone content, respectively. Moreover, a candidate-gene association analysis revealed that 11 natural GmMYB29 polymorphisms were significantly associated with isoflavone contents, and regulation of GmMYB29 expression could partially contribute to the observed phenotypic variation. Taken together, these results provide important genetic insights into the molecular mechanisms underlying isoflavone biosynthesis in soybean.


Assuntos
Glycine max/genética , Isoflavonas/biossíntese , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Regiões 5' não Traduzidas , Aciltransferases/genética , Aciltransferases/metabolismo , Isoflavonas/genética , Oxigenases/genética , Oxigenases/metabolismo , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Glycine max/metabolismo , Fatores de Transcrição/metabolismo
4.
ISA Trans ; 58: 509-19, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26089172

RESUMO

A novel Vernier-gimballing magnetically suspended flywheel with conical magnetic bearing (conical MB) can generate great gyroscopic moment by tilting the high-speed rotor. To output the gyroscopic moment, the high-speed rotor must be suspended stably and can be tilted. But when the rotor tilts, the gap between the stator and rotor of conical MB changes nonlinearly, what will cause the magnetic force and current stiffness of this conical MB to be serious nonlinear. To solve these problems, one kind of adaptive controller based on Lyapunov stability theory is designed by regarding the current stiffness of this conical MB as uncertain parameter. The validity of this adaptive control method is verified on a Vernier-gimballing MSFW with 68 Nms angular momentum and 1.7° maximum tilting angle. All experimental results indicated that this adaptive control has better performances on controlling rotor's stable suspension than existing PID control when the rotor translates or tilts.

5.
ISA Trans ; 53(6): 1892-900, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25104645

RESUMO

Two-dimensional gyroscopic torque can be produced by tilting the rotor shaft of the active magnetically suspended momentum wheel. The nonlinear magnetic torque is analyzed and then an adaptive back-stepping tracking method is proposed to deal with the nonlinearity and uncertainty. The nonlinearity of magnetic torque is represented as bounded unknown uncertainty stiffness, and an adaptive law is proposed to estimate the stiffness. Combined with back-stepping method, the proposed method can deal with the uncertainty. This method is designed by Lyapunov stability theory to ensure the stability, and its effectiveness is validated by simulations and experiments. These results indicate that this method can realize higher tracking precision and faster tracking velocity than the conventional cross feedback method to provide high precision and wide bandwidth outputting torque.

6.
Exp Ther Med ; 7(5): 1327-1331, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24940433

RESUMO

This study aimed to investigate the effect of Quanzhenyiqitang on alveolar macrophages (AMs) in a rat model of chronic obstructive pulmonary disease (COPD). In addition, the induction of apoptosis and regulation of histone deacetylase 2 (HDAC2) was studied to elucidate the underlying mechanisms of Quanzhenyiqitang treatment of COPD. Quanzhenyiqitang-treated serum was applied to AMs obtained from rats with COPD. A blank (control) group, an untreated serum group and an aminophylline group were also observed to evaluate the differences in AM apoptosis status, as well as the expression levels of caspase-9, caspase-8 and HDAC2. Compared with the control group, Quanzhenyiqitang-treated serum resulted in higher levels of caspase-9 and caspase-8 expression, increased apoptosis of AMs and increased expression of HDAC2 by AMs. In conclusion, Quanzhenyiqitang is capable of inducing apoptosis of AMs, which are the primary inflammatory cells in COPD, and modulating the expression of the important inflammatory factor HDAC2, producing an overall anti-inflammatory effect.

7.
Mol Biol Rep ; 40(8): 4737-45, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23666055

RESUMO

Carotenoid oxygenase is a key enzyme in carotenoid metabolism leading to the synthesis of two phytohormones, abscisic acid (ABA) and strigolactone, as well as norisoprenoids. Few studies have analyzed inter-relationship of the metabolic networks of these three substances. In this present paper, soybean carotenoid oxygenase genes were identified to reveal their phylogenetic relationships, and the transcriptional response of these genes to four abiotic stresses (NaCl, PEG, high and low temperature) and ABA treatment were investigated to characterize their potential roles in plant resistance. Positive selection was found in the branches of carotenoid cleavage dioxygenase (CCD1), CCD8 and NCED (9-cis-epoxycarotenoid oxygenase), indicating an adaptive evolution in these clades. In soybean eight carotenoid oxygenase genes were identified. The transcriptional responses of almost all of them under stress and ABA conditions were significantly altered when assessed by quantitative polymerase chain reaction. Notably, CCD1 and CCD4, previously known as the key genes in norisoprenoids metabolism, showed especially strong responses to the abiotic stresses and ABA treatment. Furthermore, transcription levels of CCD7 and CCD8, key genes for the strigolactone pathway, highly increased during ABA treatment providing further evidence that ABA is involved in regulating strigolactone metabolism. All of the carotenoid oxygenase genes in soybean are involved in plant abiotic stress physiology, and ABA is presumed to be a core regulatory substance. These findings provide some insights into the mechanisms that underlie the regulation of tolerance response to abiotic stresses in soybean.


Assuntos
Adaptação Biológica/genética , Regulação da Expressão Gênica de Plantas/genética , Glycine max/enzimologia , Oxigenases/genética , Filogenia , Estresse Fisiológico/genética , Ácido Abscísico/toxicidade , Teorema de Bayes , Biologia Computacional , Primers do DNA/genética , Dioxigenases/genética , Dioxigenases/metabolismo , Genoma de Planta/genética , Modelos Genéticos , Polietilenoglicóis/toxicidade , Seleção Genética , Cloreto de Sódio/toxicidade , Temperatura
8.
Chin Med J (Engl) ; 124(16): 2507-11, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21933596

RESUMO

BACKGROUND: Random flap is one kind of the most widely used skin flaps in reconstructive surgery; however, partial necrosis of its distal end remains a significant problem now. The aim of this study was to evaluate the effect of hypoxia preconditioned bone marrow mesenchymal stem cells (HpBMSCs) transplantation on ultra-long random skin flap survival in rats. METHODS: Normoxic bone marrow mesenchymal stem cells (nBMSCs) were cultured under normoxia (20% O2) and HpBMSCs under hypoxia (1% O2) for 48 hours before transplantation. Thirty Sprague-Dawley rats were randomly divided into control group, nBMSCs group and HpBMSCs group with each consisting of 10 rats. Survival area of ultra-long random skin flap on the dorsal of rats was measured seven days after flap surgery and cell transplantation. Cell survival in vivo, microvessel density and vascular endothelial growth factor (VEGF) were evaluated by histological examination and enzyme-linked immunosorbent assay. RESULTS: Compared with other two groups, flap survival area in HpBMSCs group was significantly larger (P < 0.05). Microvessel density in HpBMSCs group (36.20 ± 8.19) was higher than that in nBMSCs group (30.01 ± 5.68) and control group (17.60 ± 4.19) (P < 0.05). VEGF in HpBMSCs group ((300.05 ± 50.41) pg/g) was higher than those in nBMSCs group ((240.55 ± 33.64) pg/g) and control group ((191.65 ± 32.58) pg/g) (P < 0.05). CONCLUSION: HpBMSCs transplantation improves ultra-long random skin flap survival via promoting angiogenesis of more survival cells.


Assuntos
Células da Medula Óssea/citologia , Hipóxia Celular/fisiologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Pele/irrigação sanguínea , Retalhos Cirúrgicos/irrigação sanguínea , Animais , Células Cultivadas , Sobrevivência de Enxerto , Ratos , Ratos Sprague-Dawley
9.
J Bone Miner Metab ; 26(4): 385-93, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18600406

RESUMO

The purpose of the current study was to investigate the changes of serum proteome and discover potential biomarkers for Kashin-Beck disease (KBD) using surface-enhanced laser desorption ionization mass spectrometry (SELDI-TOF MS). The serum protein profiles from 102 cases (36 KBD patients, 16 controls in KBD areas, 33 controls in non-KBD areas, and 17 osteoarthritis controls) were detected by SELDI-TOF MS and weak cation-exchange protein chip. Differently expressed peaks in KBD were identified by comparing the data among the four groups using the nonparametric Mann-Whitney test with Bonferroni correction at a significance level of 0.05. Then, those 102 cases were used to generate a classification tree as the training set, and an additional 34 cases were collected as the test set. A classification tree was generated by Biomarker Patterns Software (Ciphergen). Multiple protein changes were detected in the KBD group, including three potential biomarkers (15 886, 5336, 6113 m/z). A classification tree with three distinct proteins was generated. The classification tree was able to distinguish the KBD patients from the controls with 88.89% specificity and 86.36% sensitivity. The study demonstrates that marked serum proteomic changes exist in KBD. The proteins represented by the differently expressed peaks are candidate biomarkers for KBD.


Assuntos
Doenças Ósseas/sangue , Proteoma/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Adulto , Idoso , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Serial de Proteínas , Proteoma/química , Reprodutibilidade dos Testes
10.
Se Pu ; 22(3): 228-30, 2004 May.
Artigo em Chinês | MEDLINE | ID: mdl-15712903

RESUMO

A gas chromatography-mass spectrometry (GC/MS) analytical method for three anorectics drugs, fenfluramine, diethylpropion and mazindol, illegally adulterated in slimming foods has been developed. They can be simultaneously identified and quantified. The samples were extracted with chloroform, and then separated by GC with an HP-5MS GC capillary column. The temperature programming was started at 70 degrees C. The temperature was held at this temperature for 2 min and then increased at 10 degrees C/min to 280 degrees C. The completely separated peaks were identified by MS with a quadrupole mass filter and quantitated in selected ion monitoring mode. Compared with the NIST98 library, the matching qualities of the drugs in foods were all over 90%. The calibration curves of the drugs were excellent with correlation coefficients between 0.9991 and 0.9999, and relative standard deviations between 1.6% and 2.2%. The recoveries were between 96.0% and 102.4%. The results demonstrated that this method is suitable for the identification and quantitation of these anorectics drugs in slimming foods.


Assuntos
Depressores do Apetite/análise , Dieta Redutora , Dietilpropiona/análise , Fenfluramina/análise , Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Mazindol/análise , Depressores do Apetite/química , Clorofórmio/química , Dietilpropiona/química , Fenfluramina/química , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Mazindol/química , Extração em Fase Sólida/métodos
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