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1.
Eur Rev Med Pharmacol Sci ; 25(4): 1974-1981, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33660808

RESUMO

OBJECTIVE: The pathogenesis of acute lung injury (ALI) is complicated, the condition is developing rapidly, and the mortality rate is high. It is a common acute and critical illness in clinic. Here, we aimed to demonstrate the function and molecular mechanism of microRNA-147b (miR-147b) in ALI. MATERIALS AND METHODS: MiR-147b mimic or miR-147b inhibitor was transfected into A549 cells to upregulate or downregulate miR-147b. The inflammatory response of A549 cells was observed by measuring the levels of inflammatory cytokines (TNF-α, IL-6, IL-1ß) and chemokines (CCL2, CCL4) by enzyme-linked immunosorbent assay (ELISA) assay. The detection of apoptosis in A549 cells relies on Cell Counting Kit-8 (CCK-8) assay, caspase-3 activity assay, and flow cytometry. Quantitative Real Time-Polymerase Chain Reaction (RT-PCR) and Western blot were employed to detect the expression of miRNA and protein. RESULTS: MiR-147b was downregulated in lipopolysaccharide (LPS)-induced ALI rats and LPS-treated A549 cells. Upregulation of miR-147b markedly suppressed LPS-induced inflammation and apoptosis of A549 cells, which was manifested by the reduction of inflammatory cytokines (TNF-α, IL-6, IL-1ß) and chemokines (CCL2, CCL4), the reduction of LDH contents, the increase of cell viability, and the decrease of caspase-3 activity and apoptosis rate of A549 cells. The downregulation of miR-147b further induced inflammation and apoptosis of A549 cells caused by LPS, which was alleviated by inhibition of p38 MAPK pathway. CONCLUSIONS: Taken together, miR-147b was downregulated in ALI, and the overexpression of miR-147b inhibited LPS-induced inflammation and apoptosis in A549 cells via inhibition of p38 MAPK signaling pathway.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Apoptose , Inflamação/metabolismo , MicroRNAs/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Células A549 , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/patologia , Animais , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Lipopolissacarídeos , Masculino , MicroRNAs/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Células Tumorais Cultivadas
2.
Phys Rev Lett ; 123(25): 257202, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31922781

RESUMO

We introduce a new approach of materials design for terahertz magnonics making use of quantum confinement of terahertz magnons in layered ferromagnets. We show that in atomically designed multilayers composed of alternating atomic layers of ferromagnetic metals one can efficiently excite different magnon modes associated with the quantum confinement in the third dimension, i.e., the direction perpendicular to the layers. We demonstrate experimentally that the magnonic band structure of these systems can be tuned by changing the material combination and the number of atomic layers. We realize the idea of opening band gaps, with a size of up to several tens of millielectronvolts, between different terahertz magnon bands and thereby report on the first step toward the realization of atomic-scale magnonic crystals.

3.
Zhonghua Jie He He Hu Xi Za Zhi ; 41(12): 954-958, 2018 Dec 12.
Artigo em Chinês | MEDLINE | ID: mdl-30522193

RESUMO

Objective: To explore the signal pathway of M2-type polarization induced by Mycobacterium tuberculosis (MTB)-specific peptide E7. Methods: Monocyte-macrophages were divided into blank control group, M1 positive stimulus group [co-stimulated with lipopolysaccharide and gamma interferon (IFN-γ)], M2 positive group(co-stimulated with IL-4 and IL-13), and E7 experimental group (with MTB-specificity polypeptide E7 stimulated). The expression of M1 type markers CD(16), IL-6, TNF-α and M2 type markers CD(163), CD(206), IL-10 were detected at 12, 18, 24 and 36 h. Furthermore, peroxisome proliferators-activated receptors-γ (PPAR-γ) blocker was used in the blank control group, M2-positive stimulus group and E7 experimental stimulus group. T test was used to compare the expression of PPAR-γ and CD(163) before and after the addition of blockers. Results: Compared with the positive control group and the blank control group, the expression of TNF-α in the E7 experimental group gradually reached the peak when macrophages were stimulated for 18 h(the relative expression was 20.02), and then the expression of TNF-α gradually decreased and the expression of CD(163) increased. The expression of CD(163) peaked at 24 h (the relative expression was 2.44). After adding the inhibitor, the expression of PPAR-γ in E7 stimulation group was lower than before blocking (before blocking 0.94±0.06, after blocking 0.69±0.09, P=0.028). CD(163) expression level was significantly lower than that before blocking (before blocking 3.95±0.61, after blocking 2.87±0.20, P=0.047). Conclusion: The MTB-specific peptide E7 induced differentiation of macrophages into M2 type, a process that may be involving PPAR-γ in just another kinase-signal transducer and activator of transcription pathway.


Assuntos
Macrófagos , Monócitos , Mycobacterium tuberculosis , Humanos , Interferon gama , Transdução de Sinais
4.
Artigo em Chinês | MEDLINE | ID: mdl-29081121

RESUMO

Objective: To investigate the reproductive health status of female workers in a railway system and possible influencing factors. Methods: From January to June, 2016, a cross-sectional epidemiological investigation was performed to collect 2 165 female workers aged 17-55 years. A women's health questionnaire was used to collect the data on their occupation and health, and their reproductive health status was analyzed. Results: The female workers exposed to occupational hazards had significantly higher incidence rates of gynecological diseases, abnormal menstruation, and infertility than those not exposed to such hazards (χ(2)=32.29, 12.42, and 4.23, respectively, all P<0.05) . There were significant differences in the incidence rates of gynecological diseases, abnormal menstruation, adverse pregnancy outcomes, and pregnancy complications between the female workers with different working forms and states (χ(2)=17.19, 23.03, 200.65, and 21.28, respectively, all P<0.05) . There were significant differences in the incidence rates of gynecological diseases, abnormal menstruation, and pregnancy complications between the female workers with different behavioral habits (χ(2)=15.65, 36.23, and 25.35, respectively, all P<0.05) . The logistic regression analysis showed that exposure to occupational hazards, married state, medium-grade professional title or above, work in shifts, sitting for a long time, standing for a long time, and video operation were risk factors for gynecological diseases, and the prevalence rate of gynecological diseases increased with age. Exposure to occupational hazards, night shifts, staying up late, and sitting for a long time were risk factors for abnormal menstruation. Exposure to occupational hazards was a risk factor for infertility. Medium-grade professional title or above was a risk factor for adverse pregnancy outcomes. Married state, medium-grade professional title or above, standing for a long time, and high mobility in job form and state were risk factors for pregnancy complications. Conclusion: Exposure to occupational hazards, job form and state, and unhealthy behavioral habits may affect reproductive health status in female workers in the railway system.


Assuntos
Nível de Saúde , Exposição Ocupacional , Saúde Ocupacional , Ferrovias , Saúde Reprodutiva , Mulheres Trabalhadoras , Adolescente , Adulto , China , Estudos Transversais , Feminino , Doenças dos Genitais Femininos/epidemiologia , Humanos , Incidência , Menstruação/fisiologia , Pessoa de Meia-Idade , Ocupações , Gravidez , Complicações na Gravidez/epidemiologia , Inquéritos e Questionários , Adulto Jovem
5.
Phys Rev Lett ; 118(12): 127203, 2017 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-28388202

RESUMO

When an ordered spin system of a given dimensionality undergoes a second order phase transition, the dependence of the order parameter, i.e., magnetization on temperature, can be well described by thermal excitations of elementary collective spin excitations (magnons). However, the behavior of magnons themselves, as a function of temperature and across the transition temperature T_{C}, is an unknown issue. Utilizing spin-polarized high resolution electron energy loss spectroscopy, we monitor the high-energy (terahertz) magnons, excited in an ultrathin ferromagnet, as a function of temperature. We show that the magnons' energy and lifetime decrease with temperature. The temperature-induced renormalization of the magnons' energy and lifetime depends on the wave vector. We provide quantitative results on the temperature-induced damping and discuss the possible mechanism, e.g., multimagnon scattering. A careful investigation of physical quantities determining the magnons' propagation indicates that terahertz magnons sustain their propagating character even at temperatures far above T_{C}.

6.
Phys Rev Lett ; 119(26): 267201, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29328716

RESUMO

Quantum confinement permits the existence of multiple terahertz magnon modes in atomically engineered ultrathin magnetic films and multilayers. By means of spin-polarized high-resolution electron energy-loss spectroscopy, we report on the direct experimental detection of all exchange-dominated terahertz confined magnon modes in a 3 ML Co film. We demonstrate that, by tuning the structural and magnetic properties of the Co film, through its epitaxial growth on different surfaces, e.g., Ir(001), Cu(001), and Pt(111), one can achieve entirely different in-plane magnon dispersions, characterized by positive and negative group velocities. Our first-principles calculations show that spin-dependent many-body correlation effects in Co films play an important role in the determination of the energies of confined magnon modes. Our results suggest a pathway towards the engineering of the group velocity of confined ultrafast magnons.

7.
Genet Mol Res ; 15(3)2016 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-27706637

RESUMO

Colorectal cancer (CRC) is a multi-factorial disease, and genetic background may contribute to its etiology. Single nucleotide polymorphisms (SNPs) in microRNAs (miRNAs) may be used as specific markers of predisposition for CRC diagnosis and prevention. In this review, we summarize and discuss recent publications evaluating the roles of miRNA SNPs in CRC. A meta-analysis was also carried out to assess the association between the five most frequently studied miRNA SNPs and CRC risk. No relationship was established between this disease and the three SNPs rs11614913, rs2910164, and rs3746444 in miR-196a-2, miR-146a, and miR-499, respectively. However, polymorphisms of miR-149 (rs2292832; CT vs TT: odds ratio [OR] = 0.816, 95% confidence interval [CI] = 0.691-0.963; CC+CT vs TT: OR = 0.834, 95%CI = 0.715-0.972) and pre-miR-27a (rs895819; GG vs AA: OR = 1.534, 95%CI = 1.148-2.049; GG+AG vs AA: OR = 1.324, 95%CI = 1.066-1.645) were found to be associated with CRC in our analysis. In conclusion, the SNPs rs2292832 in miR-149 and rs895819 in pre-miR-27a were associated with CRC susceptibility, whereas rs11614913, rs2910164, and rs3746444 in miR-196a-2, miR-146a, and miR-499, respectively, were not. Further studies should be carried out to validate these findings.


Assuntos
Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Predisposição Genética para Doença , Haplótipos , Humanos , Razão de Chances , Fatores de Risco
8.
Genet Mol Res ; 14(3): 10087-95, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26345946

RESUMO

We investigated the effects of hepatitis B virus (HBV) S/C double gene loci antisense locked nucleic acid on replication and expression of HBV in hepatitis transgenic mice. HBV mice (N = 30) were randomly divided into five groups of six mice: 5% glucose solution control, empty liposome control, single-target S, single-target C, and dual-target SC groups. An antisense locked nucleic acid fragment was injected into the mice. Serum HBsAg, serum HBV DNA, HBV C-mRNA expression in liver tissue, HbsAg and HbcAg expression in hepatocytes, serum albumin, alanine transaminase (ALT), urea nitrogen, and creatinine were detected. Liver and kidney sections were examined for the effects of antisense locked nucleic acid. The expression of HBsAg was markedly inhibited; the inhibition rates of the S, C, and SC target groups were 36.63, 31.50, and 54.87%, respectively; the replication of HBV DNA was also inhibited: 23.97, 21.13, and 35.83%, respectively. After injection at 1, 3, and 5 days, the corresponding rates for HBsAg inhibition were 14.40, 25.61, and 31.33%, and for HBV DNA inhibition they were 11.04, 19.24, and 24.13%. Compared with the control group, the differences in serum albumin, ALT, urea nitrogen, and creatinine in each group were not statistically significant, and the number of HbsAg- and HBcAg-positive cells in the mouse liver was significantly reduced. The liver and kidney tissues were normal. The gene therapy had significant inhibitory effects on the replication and expression of HBV in transgenic mice, and double-gene targeting was better than single-gene targeting.


Assuntos
DNA Antissenso/genética , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B/genética , Hepatite B/virologia , Animais , DNA Antissenso/administração & dosagem , DNA Antissenso/toxicidade , Modelos Animais de Doenças , Regulação Viral da Expressão Gênica , Hepatite B/sangue , Hepatite B/patologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Humanos , Testes de Função Renal , Testes de Função Hepática , Camundongos , Camundongos Transgênicos , RNA Mensageiro/genética , Carga Viral , Replicação Viral/genética
9.
Genet Mol Res ; 14(2): 5445-51, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-26125740

RESUMO

The aim of this study was to investigate the effects of inhibition of the hepatitis B virus (HBV) S gene by polypurine region locked nucleic acid on viral replication in cells. We designed and synthesized a locked nucleic acid, phosphorothioate oligonucleotides, unmodified oligonucleotides, and unrelated control sequence for the hepatitis B virus S gene polypurine region. HepG2.2.15 cells were transfected by cationic liposome, and fluorescence quantitative polymerase chain reaction technology (PCR) and time-resolved fluoroimmunoassay technology was utilized to monitor the content of HBV DNA, HbsAg, and HBeAg at 2, 4, 6, 8 and 10 days post-transfection. The effects on cell metabolism were detected by four methyl thiazolyl tetrazolium assay. The locked nucleic acid had an obvious effect on HBV DNA replication and HBsAg and HBeAg expression in a dose and time dependent man-ner. The inhibition rates were 52.14, 57.48, and 29.63% after 6 days, respectively. The locked nucleic acid had no significant effect on cell metabolism. The HBV S gene polypurine region locked nucleic acid could effectively inhibit the replication of HBV in vitro, and could provide an effective target for the treatment of HBV and a theoretical and experimental basis for anti-gene therapy.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Oligonucleotídeos/genética , Proteínas do Envelope Viral/biossíntese , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Replicação do DNA/efeitos dos fármacos , DNA Viral/genética , Regulação Viral da Expressão Gênica , Terapia Genética , Células Hep G2 , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Oligonucleotídeos/administração & dosagem , Proteínas do Envelope Viral/antagonistas & inibidores , Proteínas do Envelope Viral/genética
10.
Nat Commun ; 6: 6126, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25625857

RESUMO

The main idea behind magnonics is to use the elementary magnetic excitations (magnons) for information transfer and processing. One of the main challenges, hindering the application of ultrafast terahertz magnons in magnonics, has been the short lifetime of these excitations in metallic ferromagnets. Here, we demonstrate that the engineering of the electronic structure of a ferromagnetic metal, by reducing its dimensionality and changing its chemical composition, opens a possibility to strongly suppress the relaxation channels of terahertz magnons and thereby enhance the magnons' lifetime. For the first time, we report on the long-lived terahertz magnons excited in ultrathin metallic alloy films. On the basis of the first-principles calculations, we explain the microscopic nature of the long lifetime being a consequence of the peculiar electronic hybridizations of the species. We further demonstrate a way of tailoring magnon energies (frequencies) by varying the chemical composition of the film.

11.
Clin Exp Dermatol ; 38(8): 836-44, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24252077

RESUMO

BACKGROUND: Evidence has suggested that tumour necrosis factor (TNF)-α may be involved in the aetiology of psoriasis, but the underlying association of the TNF-α polymorphisms -238G/A (rs361525) and -308G/A (rs1800629) with the risk of psoriasis is still unconfirmed. AIM: This meta-analysis was performed to determine whether the TNF-α -238G/A and -308G/A polymorphisms are associated with susceptibility to psoriasis. METHODS: Eligible studies were identified by searching PubMed, EMBASE, CNKI (China National Knowledge Infrastructure), CBM (Chinese biomedical literature database) and WANFANG databases within a range of published years from 1990 to August 2012. The odds ratio (OR) and 95% confidence interval (CI) were used to assess the different associations. RESULTS: In total, 17 studies with 2847 cases and 2222 controls were found for -238G/A and 20 studies with 2975 cases and 2243 controls for -308G/A. The pooled results showed an overall increased risk of psoriasis for the -238G/A polymorphism (OR = 2.06, 95% CI = 1.45-2.94, P < 0.001 for AA/GA vs. GG) and a reduced psoriasis risk with the -308G/A polymorphism (OR = 0.68, 95% CI = 0.59-0.79, P < 0.001 for AA/GA vs. GG). This association was only present in early-onset psoriasis (OR = 3.68, 95% CI = 2.17-6.24, P < 0.001 for -238G/A; OR = 0.56, 95% CI = 0.43-0.72, P < 0.001 for -308G/A), whereas there was no association (OR = 0.98, 95% CI = 0.56-1.70, P = 0.92 for -238G/A) or a unreliable association (OR = 0.66, 95% CI = 0.46-0.94, P = 0.02 for -308G/A) in late-onset psoriasis. CONCLUSIONS: This meta-analysis suggests that the TNF-α -238 and -308 promoter polymorphisms may play different roles in conferring susceptibility to psoriasis. Functional and well-designed studies should be conducted to confirm these results.


Assuntos
Polimorfismo Genético , Psoríase/genética , Fator de Necrose Tumoral alfa/genética , Povo Asiático/genética , Predisposição Genética para Doença , Humanos , Razão de Chances , Regiões Promotoras Genéticas/genética , População Branca/genética
12.
Nat Nanotechnol ; 8(11): 853-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24056902

RESUMO

The fundamental interactions between magnetic moments at interfaces have an important impact on the properties of layered magnetic structures. Hence, a direct probing of these interactions is highly desirable for understanding a wide range of phenomena in low-dimensional solids. Here we propose a method for probing the magnetic exchange interaction at buried interfaces using spin-polarized electrons and taking advantage of the collective nature of elementary magnetic excitations (magnons). We demonstrate that, for the case of weak coupling at the interface, the low-energy magnon mode is mainly localized at the interface. Because this mode has the longest lifetime of the modes and has a finite spectral weight across the layers on top, it can be probed by electrons. A comparison of experimental data and first-principles calculations leads to the determination of the interface exchange parameters. This method may help the development of spectroscopy of buried magnetic interfaces.

13.
Phys Rev Lett ; 109(20): 207201, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23215520

RESUMO

We present a combined experimental and theoretical study of the interplay between the atomic structure and the magnon excitations in low dimensional ferromagnets. Two monolayer thick Fe films on W(110) with and without a Au buffer layer are investigated. Our experiments show that adding the Au layer leads to a significant softening of the magnons. First-principles calculations confirm the experimental results revealing a strong dependency of exchange interactions on the atomic structure. It is observed that the intralayer exchange interactions increase with increasing distance between Fe layers. This unusual relationship is attributed to the complexity of the electronic structure and the contribution of different orbitals to the hybridization and exchange interaction. Our results suggest a way of tailoring magnetic excitations in low-dimensional magnetic structures.

14.
Phys Rev Lett ; 105(17): 176602, 2010 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-21231064

RESUMO

We report that Bi2Se3 thin films can be epitaxially grown on SrTiO3 substrates, which allow for very large tunablity in carrier density with a back gate. The observed low field magnetoconductivity due to weak antilocalization (WAL) has a very weak gate-voltage dependence unless the electron density is reduced to very low values. Such a transition in WAL is correlated with unusual changes in longitudinal and Hall resistivities. Our results suggest a much suppressed bulk conductivity at large negative gate voltages and a possible role of surface states in the WAL phenomena.

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