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3.
Zhonghua Yi Xue Za Zhi ; 97(32): 2528-2532, 2017 Aug 22.
Artigo em Chinês | MEDLINE | ID: mdl-28835062

RESUMO

Objective: To explore the effects of chronic intermittent hypoxia (CIH) on left ventricular myocardial contractibility in a rabbit model of obstructive sleep apnea (OSA). Methods: Based on random number table, twenty-four rabbits were randomly divided into three groups: operation, sham, and control groups, each with 8 rabbits. The rabbit model for OSA in operation group was established by repeatedly closing the airway and then reopening it. Upper airway obstructions were conducted on rabbits every day, which were alternately closed for 15 s and then reopened for 75 s in a 90 s-long cycle, for 8 h each day over 3 months. The sham rabbits were subjected to the same surgical procedure but no airway obstructions were applied. The control animals were subjected to no intervention. The blood pressure, left ventricular function parameters were assessed before and after the experiment. And the relative expressions of myosin heavy chain α/ß (α-MHC and ß-MHC) mRNAs in myocardium were observed for all rabbits by real time fluorescent quantitative polymerase chain reaction 3 months later. Results: After 3 months, all rabbits in the operation group manifested sleepiness and the blood pressure rose gradually [(114.25±4.20) vs (93.88±2.10) mmHg, P<0.01]. Compared with the sham operation and the control groups, the left ventricular end-systolic volume [(6.05±1.62) vs (2.83±0.49) and (2.74±0.32) ml, P<0.001] and the left ventricular end-diastolic volume [(1.61±0.78) vs (0.83±0.13) and (0.82±0.10) ml] in operation group were obviously higher, the left ventricular ejection fraction [(63.9±4.2) % vs (74.3±2.5) % and (75.8±3.8) %], left ventricular fractional shortening [(32.2±2.1) % vs (41.8±1.8) % and (42.1±1.8) %] and stroke volume [(1.46±0.13) vs (1.93±0.21) and (1.98±0.24) ml/s] were decreased (all P<0.001). Besides, the maximal rate of the increase of left ventricular pressure [(4 154±360) vs (6 802±492) and (6 759±206) mmHg/s], the maximal rate of the decrease of left ventricular pressure [(4 994±621) vs (6 330±314) and (6 591±225) mmHg/s] in the operation group decreased markedly, left ventricular end diastolic pressure (LVEDP) increased [(6.5±1.6) vs (3.3±0.8) and (3.2±0.9) mmHg] (all P<0.001). The relative expression of α-MHC mRNA in left ventricular myocardial tissue was lower and the relative expression of ß-MHC mRNA was higher in operation group than those in the sham operation and the control groups (P<0.05). There were no significant difference in the relevant indicators of cardiac function, and in the relative expressions of α-MHC mRNA and the ß-MHC mRNA between the control group and the sham operation group (P>0.05). Conclusions: Repeated intermittent hypoxia can induce hypertension and myocardial contractibility damage in OSA model rabbit simulating upper airway obstruction.


Assuntos
Miocárdio , Apneia Obstrutiva do Sono , Animais , Pressão Sanguínea , Ventrículos do Coração , Hipóxia , Coelhos , Função Ventricular Esquerda
4.
Beijing Da Xue Xue Bao Yi Xue Ban ; 49(3): 383-387, 2017 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-28628136

RESUMO

OBJECTIVE: To investigate the effect of equol on the proliferation of colom cancer cells and to explore the mechanisms. METHODS: Colon cancer cells (DLD1,HCT15,COLO205,LOVO,SW480) were incubated, the cell proliferation was identified by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell proliferation assay. Reverse transcription PCR and Western blot were used to measure the mRNA and the protein expression of estrogen receptor and nuclear factor (erythroid-derived 2)-like 2 (Nrf2)in the colon cancer cells, respectively. Moreover, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell proliferation assay was used to investigate the effect of estrogen receptor(ER) inhibitor,ERα agonist, and estrogen receptor ERßagonist on the cell proliferation. RESULTS: ERα was faintly expressed in the DLD-1 and HCT-15 cells. However, ERß expression in DLD1, HCT15, COLO205, LOVO, and SW480 colon cancer cells. Different concentrations of equol (0, 0.5, 1, 5, 10 µmol/L) significantly inhibited the growth of HCT-15 cell with the expression of ERα and ERß.More-over, different concentrations of equol (0, 0.5, 1, 5, 10 µmol/L) significantly inhibited the growth of LOVO, and SW480 cells with the ERß expression in a dose-dependent manner as demonstrated with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell proliferation assay. mRNA expressions of ERα and ERß in HCT-15 were stimulated significantly. Western blotting proved that the protein expressions of ERα and ERß increased with the increasing of equol dose. Moreover we found significant difference of Nrf2 protein expression in HCT-15 cell stimulated by different concentrationss of equol. After the similation of estrogen receptor inhibitor, ERα agonist, or ERß agonist, we found that only dif-ferent concentrations of ERß agonist(0, 1, 10, 100, 1 000, 10 000 nmol/L) significantly inhibited the growth of HCT-15, LOVO, and SW480 in adose-dependent manner. Estrogen receptor inhibitor and ERα agonistdid not present significant effect on the cell proliferation of HCT-15, LOVO, and SW480. CONCLUSION: Equol inhibited the colon cancer cell proliferation by its estrogenic activities and antioxidant activities.


Assuntos
Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , Equol/farmacologia , Receptor beta de Estrogênio , Fitoestrógenos/farmacologia , Receptor alfa de Estrogênio , Humanos , RNA Mensageiro/metabolismo , Receptores de Estrogênio
5.
Artigo em Inglês | MEDLINE | ID: mdl-28320722

RESUMO

This study further evaluated the in vitro and in vivo anti-Helicobacter pylori activities and potential underlying mechanism of patchouli alcohol (PA), a tricyclic sesquiterpene. In the in vitro assay, the capacities of PA to inhibit and kill H. pylori were tested on three standard strains at different pH values and on 12 clinical isolates. The effects of PA on H. pylori adhesion (and its alpA, alpB, and babA genes), motility (and its flaA and flaB genes), ultrastructure, and flagellation were investigated. Moreover, the H. pylori resistance to and postantibiotic effect (PAE) of PA were determined. Furthermore, the in vivo effects of PA on H. pylori eradication and gastritis were examined. Results showed that MICs of PA against three standard strains (pH 5.3 to 9) and 12 clinical isolates were 25 to 75 and 12.5 to 50 µg/ml, respectively. The killing kinetics of PA were time and concentration dependent, and its minimal bactericidal concentrations (MBCs) were 25 to 75 µg/ml. In addition, H. pylori adhesion, motility, ultrastructure, and flagellation were significantly suppressed. PA also remarkably inhibited the expression of adhesion genes (alpA and alpB) and motility genes (flaA and flaB). Furthermore, PA treatment caused a longer PAE and less bacterial resistance than clarithromycin and metronidazole. The in vivo study showed that PA can effectively eradicate H. pylori, inhibit gastritis, and suppress the expression of inflammatory mediators (COX-2, interleukin 1ß, tumor necrosis factor alpha, and inducible nitric oxide synthase [iNOS]). In conclusion, PA can efficiently kill H. pylori, interfere with its infection process, and attenuate gastritis with less bacterial resistance, making it a potential candidate for new drug development.


Assuntos
Antibacterianos/farmacologia , Gastrite/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Sesquiterpenos/farmacologia , Adesinas Bacterianas/biossíntese , Adesinas Bacterianas/genética , Animais , Aderência Bacteriana/efeitos dos fármacos , Proteínas da Membrana Bacteriana Externa/biossíntese , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Claritromicina/farmacologia , Feminino , Flagelina/biossíntese , Flagelina/genética , Gastrite/microbiologia , Expressão Gênica/efeitos dos fármacos , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Hidroliases/biossíntese , Hidroliases/genética , Inflamação/tratamento farmacológico , Inflamação/microbiologia , Masculino , Metronidazol/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Oxirredutases/biossíntese , Oxirredutases/genética
6.
Clin Exp Dermatol ; 42(1): 21-29, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27735067

RESUMO

BACKGROUND: There are conflicting reports on the correlation between vitiligo and the levels of either superoxide dismutase (SOD) or malondialdehyde (MDA). AIM: To clarify the association between vitiligo and SOD or MDA. METHODS: Relevant published articles were searched according to our eligibility criteria. A meta-analysis was conducted to pool estimates of the standardized mean difference (SMD) with 95% CI. RESULTS: Patients with either the active or stable vitiligo had higher levels of both SOD (stable: SMD = 1.61, 95% CI 0.66-2.56, P = 0.001; active: SMD = 2.56, 95% CI 1.13-3.99, P < 0.001) and MDA (stable: SMD = 2.70, 95% CI 1.81-3.59, P < 0.001; active: SMD = 3.50, 95% CI 2.29-4.71, P < 0.001), compared with healthy controls. CONCLUSIONS: This meta-analysis showed a significant association between vitiligo and high levels of both SOD and MDA.


Assuntos
Malondialdeído/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Vitiligo/metabolismo , Humanos
7.
Clin Exp Dermatol ; 40(6): 682-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25917572

RESUMO

BACKGROUND: Tumour necrosis factor (TNF)-α is considered to play a central role in the pathogenesis of acne. AIM: To estimate the association between the TNF-α 308G>A polymorphism and the pathogenesis of acne. METHODS: A literature search of the PubMed and CNKI databases from inception to December 2013 was conducted. Meta-analyses were performed, and the OR and 95% CI calculated. The strength of association was assessed under five genetic models: allele (A vs. G), dominant (AA+AG vs. GG), recessive (AA vs. GG+AG), homozygous (AA vs. GG), and heterozygous (AA vs. AG). RESULTS: Seven case-control studies were included, with a total of 987 patients with acne and 1078 healthy controls. The meta-analysis result showed a significant association between TNF-α 308G>A and the pathogenesis of acne under the recessive (OR = 3.13, 95% CI 1.67-5.86, P < 0.001), homozygous (OR = 3.03, 95% CI 1.63-5.63, P < 0.001) and heterozygous (OR = 3.16, 95% CI 1.61-6.20, P < 0.001) models. The subgroup analysis showed a significant association with male sex (recessive: OR = 3.77, 95% CI 1.26-11.25, P = 0.02, homozygous: OR = 3.25, 95% CI 1.03-10.22, P = 0.04) and severe acne (recessive: OR = 4.62, 95% CI 1.73-12.34, P < 0.01; homozygous: OR = 3.41, 95% CI 1.18-9.89, P = 0.02). CONCLUSION: Our findings indicate that genotype AA of TNF-α 308G>A may contribute to the pathogenesis of acne. Thus, detection of the TNF-α 308G>A polymorphism may be a promising biomarker for the early detection of acne.


Assuntos
Acne Vulgar/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/genética , Alelos , Estudos de Casos e Controles , Genótipo , Humanos , Fatores de Risco
8.
Clin Exp Dermatol ; 40(7): 794-803, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25788285

RESUMO

BACKGROUND: It has been reported that polymorphisms of the vitamin D receptor gene (VDR) such as ApaI or BsmI may affect the risk of vitiligo. However, the results have been inconsistent. AIM: To evaluate the association between two common polymorphisms (ApaI and BsmI) in the VDR gene and the susceptibility to vitiligo. METHODS: The PubMed, Cochrane Library and China National Knowledge Infrastructure (CNKI) databases were searched, and OR with 95% CI was calculated. The strength of association and vitiligo risk was assessed under five genetic models: allele, dominant, recessive, homozygous and heterozygous. RESULTS: Six relevant studies were identified, including five studies that assessed the ApaI polymorphism and four the BsmI polymorphism (some overlapped). The meta-analysis results indicated that either the ApaI or the BsmI gene polymorphism may increase the risk of vitiligo in East Asian populations (aa + Aa vs. AA: OR = 1.40, 95% CI 1.01-1.96, P < 0.05; bb vs. Bb + BB: OR = 1.32, 95% CI 1.09-1.59, P < 0.01). No publication bias was detected in this meta-analysis. CONCLUSION: The current meta-analysis suggests that the ApaI a allele or BsmI bb genotype are associated with the risk of vitiligo in East Asian populations. Thus, these polymorphisms could be potential biomarkers for early detection of vitiligo.


Assuntos
Desoxirribonucleases de Sítio Específico do Tipo II/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Vitiligo/genética , Alelos , Povo Asiático/genética , China , Estudos de Associação Genética , Genótipo , Humanos , Fatores de Risco
9.
Sheng Wu Gong Cheng Xue Bao ; 16(4): 469-73, 2000 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-11051821

RESUMO

The mutants of Q20L and G247D of glucose isomerase (GI) were constructed by in vitro site-directed mutagenesis of GI gene with double-primersmethod. The recombinant plasmids pTKD-GIQ20L and pTKD-GIG247D were expressed in E. coli K38 strain. The comparison experiments of mutant enzymes with wild-type GI showed that: (1) the optimum temperature of GIQ20L was decreased by 5 degrees C. Its thermostability was only 78% half-time of the wild type. But its substrate affinity was enhanced. (2) The specific-activity of GIG247D was increased by 33%, and the optimum pH was lowered by 0.6 unit. However, the thermostability of GIG247D was decreased. We supposed, based on the above facts and 0.19 nm resolution crystal structure of SM33GI, that Gln20 locates between alpha 0-helix and alpha 1-helix, the substitution of hydrophobic side chain of Leu for hydrophilic side chain of Gln may enhance the hydrophobic interaction of the molecular surface, leading to the decrease of the stability and thermostability of GIQ20L. Gly247 which is the last amino acid of a beta-sheet from 242 to 247 residues locates in the active core of GI. After replacement, Asp247 which has strong negative electricity may change the electrostatic distribution and influence the charge transfer processes of the active core. So the specific-activity of GIG247D was increased. The introduced charge could alter the pKa of dissociable groups and make the optimum pH lower. In addition, the side chain of Asp247 seems to be very crowded in the surrounding space conformation and is easy to exclude with the other side chains, therefore influences the stability of beta-sheet. Furthermore, Asp247 is in the vicinity of the interface of subunits, so it could interfere with the stability of the interaction between subunits. Thus, the GIG247D decreased the thermostability of SM33GI. The higher enzyme activity and the lower optimum pH will be very useful for industrial production of GI.


Assuntos
Aldose-Cetose Isomerases/química , Aldose-Cetose Isomerases/fisiologia , Estabilidade Enzimática , Temperatura Alta , Concentração de Íons de Hidrogênio , Modelos Moleculares , Mutagênese Sítio-Dirigida , Relação Estrutura-Atividade
10.
Biomed Chromatogr ; 9(3): 155-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7655306

RESUMO

A gas chromatography method using steam as the carrier gas was established for the determination of salicylic acid in plasma. A 0.5 mL plasma sample was mixed with 0.5 mL of 6N HCl and then extracted with 2 mL of dichloromethane. The dichloromethane was evaporated to dryness and the residue was redissolved in 0.5 mL of water and then analysed by gas chromatography using steam as the carrying gas. The result was calculated by external standardization.


Assuntos
Cromatografia Gasosa/métodos , Salicilatos/sangue , Ionização de Chama , Reprodutibilidade dos Testes , Ácido Salicílico , Vapor
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