Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
1.
Ann Gen Psychiatry ; 23(1): 19, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730281

RESUMO

BACKGROUND: Anxiety disorders can cause serious physical and psychological damage, so many anxiety scales have been developed internationally to measure anxiety disorders, but due to the cultural differences and cultural dependence of quality of life between Chinese and Western cultures, it is difficult to reflect the main characteristics of Chinese patients. Therefore, we developed a scale suitable for Chinese patients with anxiety disorders: the Anxiety Disorders Scale of the Quality of Life Instruments for Chronic Diseases (QLICD-AD), hoping to achieve satisfactory QOL assessments for anxiety disorders. OBJECTIVES: Items from the Anxiety Disorders Scale of the Quality of Life in Chronic Disease Instrument QLICD-AD system were analyzed using CTT and IRT to lay the groundwork for further refinement of the scale to accurately measure anxiety disorders. METHODS: 120 patients with anxiety disorder were assessed using the QLICD-AD (V2.0). Descriptive statistics, variability method, correlation coefficient method, factor analysis and Cronbach's coefficient of CTT, and graded response model (GRM) of item response theory were used to analyze the items of the scale. RESULT: CTT analysis showed that the standard deviation of each item was between 0.928 and 1.466; Pearson correlation coefficients of item-to-domain were generally greater than 0.5 and also greater than that of item-to-other domain; the Cronbach 's of the total scale was 0.931, α of each domain was between 0.706 and 0.865. IRT analysis showed that the discrimination was between 1.14 and 1.44. The difficulty parameter of all items increased with the increase of grade. But some items (GPH6,GPH8,GPS3,GSO2-GSO4,AD2,AD5) difficulty parameters were less than 4 or greater than 4. The average of information amount was between 0.022 and 0.910. CONCLUSION: Based on CTT and IRT analysis, most items of the QLICD-AD (V2.0) scale have good performance and good differentiation, but a few items still need further revision. Suggests that the QLICD-AD (V2.0) appears to be a valid measure of anxiety disorders. It may effectively improve the diagnosticity of anxiety disorders, but due to the limitations of the current sample, further validation is needed in a broader population extrapolation trial.

2.
ACS Appl Bio Mater ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701399

RESUMO

Physicochemical properties of nanoparticles, such as particle size, surface charge, and particle shape, have a significant impact on cell activities. However, the effects of surface functionalization of nanoparticles with small chemical groups on stem cell behavior and function remain understudied. Herein, we incorporated different chemical functional groups (amino, DETA, hydroxyl, phosphate, and sulfonate with charges of +9.5, + 21.7, -14.1, -25.6, and -37.7, respectively) to the surface of inorganic silica nanoparticles. To trace their effects on mesenchymal stem cells (MSCs) of rat bone marrow, these functionalized silica nanoparticles were used to encapsulate Rhodamine B fluorophore dye. We found that surface functionalization with positively charged and short-chain chemical groups facilitates cell internalization and retention of nanoparticles in MSCs. The endocytic pathway differed among functionalized nanoparticles when tested with ion-channel inhibitors. Negatively charged nanoparticles mainly use lysosomal exocytosis to exit cells, while positively charged nanoparticles can undergo endosomal escape to avoid scavenging. The cytotoxic profiles of these functionalized silica nanoparticles are still within acceptable limits and tolerable. They exerted subtle effects on the actin cytoskeleton and migration ability. Last, phosphate-functionalized nanoparticles upregulate osteogenesis-related genes and induce osteoblast-like morphology, implying that it can direct MSCs lineage specification for bone tissue engineering. Our study provides insights into the rational design of biomaterials for effective drug delivery and regenerative medicine.

3.
Sci Rep ; 14(1): 8954, 2024 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637566

RESUMO

Rheumatoid Arthritis is a more serious threatening to people and suitable for QOL measurement. A few specific QOL instruments are available without considering Chinese culture. The present study was aimed to develop and validate the Rheumatoid Arthritis Scale among the System of Quality of Life Instruments for Chronic Diseases (QLICD-RA V2.0). The data collected from 379 patients with RA was used to evaluate the psychometric properties of the scale. The reliability was evaluated by the internal consistency Cronbach's α, test-retest reliability Pearson correlation r and intra-class correlation (ICC). We evaluated the construct validity and criteria-related validity by correlation analysis and structural equation modeling. We compared the differences in scores of QLICD-RA before and after treatment and used the Standard Response Mean (SRM) to assess the responsiveness. The results showed that the internal consistency coefficient Cronbach's α values were greater than 0.70. The correlations r and ICCs were greater than 0.80. The correlation analysis and structural equation modeling confirmed good construct validity and criterion-related validity. The SRM ranges from 0.07 to 0.27 for significant domains/facets. It concluded that QLICD-RA (2.0) is a reliable and valid instrument to measure QOL among patients with RA.


Assuntos
Artrite Reumatoide , Qualidade de Vida , Humanos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Artrite Reumatoide/diagnóstico , Doença Crônica , Psicometria/métodos
4.
J Med Microbiol ; 73(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38668646

RESUMO

Background. Actinobacillus pleuropneumoniae, a member of the Pasteurellaceae family, is known for its highly infectious nature and is the primary causative agent of infectious pleuropneumonia in pigs. This disease poses a considerable threat to the global pig industry and leads to substantial economic losses due to reduced productivity, increased mortality rates, and the need for extensive veterinary care and treatment. Due to the emergence of multi-drug-resistant strains, Chinese herbal medicine is considered one of the best alternatives to antibiotics due to its unique mechanism of action and other properties. As a type of Chinese herbal medicine, Rhein has the advantages of a wide antibacterial spectrum and is less likely to develop drug resistance, which can perfectly solve the limitations of current antibacterial treatments.Methods. The killing effect of Rhein on A. pleuropneumoniae was detected by fluorescence quantification of differential expression changes of key genes, and scanning electron microscopy was used to observe the changes in A. pleuropneumoniae status after Rhein treatment. Establishing a mouse model to observe the treatment of Rhein after A. pleuropneumoniae infection.Results. Here, in this study, we found that Rhein had a good killing effect on A. pleuropneumoniae and that the MIC was 25 µg ml-1. After 3 h of action, Rhein (4×MIC) completely kills A. pleuropneumoniae and Rhein has good stability. In addition, the treatment with Rhein (1×MIC) significantly reduced the formation of bacterial biofilms. Therapeutic evaluation in a murine model showed that Rhein protects mice from A. pleuropneumoniae and relieves lung inflammation. Quantitative RT-PCR (Quantitative reverse transcription polymerase chain reaction is a molecular biology technique that combines both reverse transcription and polymerase chain reaction methods to quantitatively detect the amount of a specific RNA molecule) results showed that Rhein treatment significantly downregulated the expression of the IL-18 (Interleukin refers to a class of cytokines produced by white blood cells), TNF-α, p65 and p38 genes. Along with the downregulation of genes such as IL-18, it means that Rhein has an inhibitory effect on the expression of these genes, thereby reducing the activation of inflammatory cells and the production of inflammatory mediators. This helps reduce inflammation and protects tissue from further damage.Conclusions. This study reports the activity of Rhein against A. pleuropneumoniae and its mechanism, and reveals the ability of Rhein to treat A. pleuropneumoniae infection in mice, laying the foundation for the development of new drugs for bacterial infections.


Assuntos
Infecções por Actinobacillus , Actinobacillus pleuropneumoniae , Antraquinonas , Antibacterianos , Animais , Antraquinonas/farmacologia , Antraquinonas/uso terapêutico , Actinobacillus pleuropneumoniae/efeitos dos fármacos , Actinobacillus pleuropneumoniae/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Camundongos , Infecções por Actinobacillus/tratamento farmacológico , Infecções por Actinobacillus/microbiologia , Infecções por Actinobacillus/veterinária , Suínos , Modelos Animais de Doenças , Feminino , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Pulmão/microbiologia , Pulmão/patologia , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/microbiologia
5.
Nat Commun ; 15(1): 3201, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615046

RESUMO

Yttrium iron garnet, a material possessing ultralow magnetic damping and extraordinarily long magnon diffusion length, is the most widely studied magnetic insulator in spintronics and magnonics. Field-free electrical control of perpendicular yttrium iron garnet magnetization with considerable efficiency is highly desired for excellent device performance. Here, we demonstrate such an accomplishment with a collinear spin current, whose spin polarization and propagation direction are both perpendicular to the interface. Remarkably, the field-free magnetization switching is achieved not only with a heavy-metal-free material, Permalloy, but also with a higher efficiency as compared with a typical heavy metal, Pt. Combined with the direct and inverse effect measurements, we ascribe the collinear spin current to the anomalous spin Hall effect in Permalloy. Our findings provide a new insight into spin current generation in Permalloy and open an avenue in spintronic devices.

6.
Ear Nose Throat J ; : 1455613231223352, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229415

RESUMO

Background: Pharyngeal packs are employed to mitigate postoperative nausea and vomiting (PONV) and have become prevalent in dental and otolaryngological surgeries. However, their clinical efficacy continues to be a topic of debate. The objective of the present study was to conduct a quantitative assessment of the impact of pharyngeal packing in dental and otolaryngological surgeries through meta-analysis. Methods: We identified relevant randomized controlled trials (RCTs) through systematic searches of online databases, including PubMed, Embase, and Cochrane Central. Potential eligible studies were evaluated using the Jadad scoring system (range 0-5 points), with only high-quality RCTs (3 points or more) being included. The incidence of PONV, morbidity, and the level of throat pain were aggregated and estimated. Publication bias was evaluated using funnel plot symmetry and the Egger test. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was utilized to rate the evidence. Results: Ten high-quality RCTs comprising 1026 participants were ultimately included. Subsequent quantitative pooled estimation unveiled that the utilization of pharyngeal packing did not lead to a significant reduction in the incidence of nausea (P = .272), vomiting (P = .775), overall PONV (P = .118), or throat pain (P = .149). By contrast, the application of pharyngeal packs was found to significantly increase the level of throat pain (P = .003). No obvious publication bias was detected, and the majority of evidence was rated high or moderate. Conclusion: Based on the existing evidence, we conclude that pharyngeal packing lacks clinical benefit and is not advised for dental and otolaryngological surgeries.

7.
J Colloid Interface Sci ; 658: 610-616, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38134669

RESUMO

Air-oxidation is an effective strategy to obtain promising carbon materials from asphalt for sodium-ion batteries. However, this method would generate a vast amount of gaseous pollutant, which pose challenges for recycling. Herein, a simple, cost-effective and environmentally friendly liquid-phase oxidation method is proposed. The oxygen-containing functional groups (-NO2) are introduced into asphalt, which effectively prevents the melting of asphalt and rearrangement of carbon layers during subsequent carbonization process. As a result, a carbon material with notable disorder degree, large interlayer spacing and abundant closed pores, is prepared. The as-prepared product demonstrates an impressive initial Coulombic efficiency of 88.3 % and an enhanced specific capacity of 317.0 mA h g-1, which is 2.6 times that of the pristine product. Moreover, when assembled with a Na3.32Fe2.34(P2O7)2 cathode, the full-cell delivers a high reversible capacity of 271.7 mA h g-1 at 30 mA g-1 with superb cycle life. This study offers a novel oxidation strategy and provides a solution for producing highly disordered carbon anodes from soft carbon precursors.

8.
Chin Med J (Engl) ; 136(24): 2948-2959, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38018259

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine can induce a potent cellular and humoral immune response to protect against SARS-CoV-2 infection. However, it was unknown whether SARS-CoV-2 vaccination can induce effective natural killer (NK) cell response in people living with human immunodeficiency virus (PLWH) and healthy individuals. METHODS: Forty-seven PLWH and thirty healthy controls (HCs) inoculated with SARS-CoV-2 inactivated vaccine were enrolled from Beijing Youan Hospital in this study. The effect of SARS-CoV-2 vaccine on NK cell frequency, phenotype, and function in PLWH and HCs was evaluated by flow cytometry, and the response of NK cells to SARS-CoV-2 Omicron Spike (SARS-2-OS) protein stimulation was also evaluated. RESULTS: SARS-CoV-2 vaccine inoculation elicited activation and degranulation of NK cells in PLWH, which peaked at 2 weeks and then decreased to a minimum at 12 weeks after the third dose of vaccine. However, in vitro stimulation of the corresponding peripheral blood monocular cells from PLWH with SARS-2-OS protein did not upregulate the expression of the aforementioned markers. Additionally, the frequencies of NK cells expressing the activation markers CD25 and CD69 in PLWH were significantly lower than those in HCs at 0, 4 and 12 weeks, but the percentage of CD16 + NK cells in PLWH was significantly higher than that in HCs at 2, 4 and 12 weeks after the third dose of vaccine. Interestingly, the frequency of CD16 + NK cells was significantly negatively correlated with the proportion of CD107a + NK cells in PLWH at each time point after the third dose. Similarly, this phenomenon was also observed in HCs at 0, 2, and 4 weeks after the third dose. Finally, regardless of whether NK cells were stimulated with SARS-2-OS or not, we did not observe any differences in the expression of NK cell degranulation markers between PLWH and HCs. CONCLUSION: s:SARS-CoV-2 vaccine elicited activation and degranulation of NK cells, indicating that the inoculation of SARS-CoV-2 vaccine enhances NK cell immune response.


Assuntos
COVID-19 , Infecções por HIV , Humanos , Vacinas contra COVID-19/uso terapêutico , SARS-CoV-2 , Células Matadoras Naturais , Anticorpos Antivirais
9.
Nano Lett ; 23(17): 8171-8179, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37638840

RESUMO

Despite its important role in understanding ultrafast spin dynamics and revealing novel spin/orbit effects, the mechanism of the terahertz (THz) emission from a single ferromagnetic nanofilm upon a femtosecond laser pump still remains elusive. Recent experiments have shown exotic symmetry, which is not expected from the routinely adopted mechanism of ultrafast demagnetization. Here, by developing a bidirectional pump-THz emission spectroscopy and associated symmetry analysis method, we set a benchmark for the experimental distinction of the THz emission induced by various mechanisms. Our results unambiguously unveil a new mechanism─anomalous Nernst effect (ANE) induced THz emission due to the ultrafast temperature gradient created by a femtosecond laser. Quantitative analysis shows that the THz emission exhibits interesting thickness dependence where different mechanisms dominate at different thickness ranges. Our work not only clarifies the origin of the ferromagnetic-based THz emission but also offers a fertile platform for investigating the ultrafast optomagnetism and THz spintronics.

10.
Am Surg ; 89(12): 6147-6156, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37309604

RESUMO

OBJECTIVE: Surgery is an effective clinical approach that has been used for the treatment of gastric lymphoma. However, its specific effect on the prognosis of patients with gastric lymphoma remains largely unknown. The current meta-analysis aimed to identify the effect of surgery on the prognosis of gastric lymphoma. METHODS: We searched the MEDLINE, Embase, and Cochrane Central databases to obtain relevant studies investigating the influence of surgery on overall survival (OS) and relapse-free survival (RFS). We extracted the hazard ratios (HRs) and associated 95% confidence intervals (CIs) of each included report for pooled analysis. We assessed heterogeneity (I2 statistic) and funnel plots to select the data models and evaluate publication bias. RESULTS: Ultimately, we included 12 studies containing 26 comparisons in the current quantitative meta-analysis. The analysis revealed that surgery had no significant effect on OS (HR .83, P = .13) or RFS (HR .78, P = .08). However, subgroup analysis revealed that the effect of surgery on OS differed significantly between the surgery plus conservative therapy subgroup and the conservative therapy alone groups, with HR = .69 (P = .01). No significant publication bias was detected regarding the main outcomes. CONCLUSION: Surgery had a limited effect on the prognosis of patients with gastric lymphoma. However, the use of surgery as an additional therapy may confer potential benefits. This was an interesting research direction, and additional high-quality, large-scale randomized controlled trials should be conducted.


Assuntos
Linfoma não Hodgkin , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Prognóstico , Modelos de Riscos Proporcionais
11.
Nano Lett ; 22(23): 9389-9395, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36416790

RESUMO

2H-NbSe2 is a prototypical charge-density-wave (CDW) system, exhibiting such a symmetry-breaking quantum ground state in its bulk and down to a single-atomic-layer limit. However, how this state depends on dimensionality and what governs the dimensionality effect remain controversial. Here, we experimentally demonstrate a robust 3 × 3 CDW phase in both freestanding and substrate-supported bilayer NbSe2, far above the bulk transition temperature. We exclude environmental effects and reveal a strong temperature and thickness dependence of Raman intensity from an axially vibrating A1g phonon mode, involving Se ions. Using first-principles calculations, we show that these result from a delicate but profound competition between the intra- and interlayer bonding formed between Se-pz orbitals. Our results suggest the crucial role of Se out-of-plane displacement in driving the CDW distortion, revealing the Se-dominated dimensionality effect and establishing a new perspective on the chemical bonding and mechanical stability in layered CDW materials.

12.
Artigo em Inglês | MEDLINE | ID: mdl-36293724

RESUMO

With the rapid socioeconomic development of China, studies related to Internet use and civil servants' happiness have become a research hotspot in Chinese academia. This study empirically analysed the impact of Internet use on the happiness of Chinese civil servants using a sample of 3793 civil servants in Hunan Province, China. It showed that Internet use significantly enhanced the subjective well-being of Chinese civil servants. Furthermore, heterogeneity analysis revealed significant heterogeneity in the effect of the Internet on civil servants' happiness, which varied across civil service groups with different education and gender. Moreover, the effect of Internet use on the happiness of the male and better educated civil servant groups was more pronounced than in the female and less educated civil servant groups. Additionally, mediation analysis revealed that Internet use and the happiness of civil servants were not linear, with health having a significant mediating effect. This indicates that Internet use helps civil servants maintain good health, and thereby enhances the happiness of civil servants. In addition, we also use a propensity score matching model (PSM) to address the endogeneity problem due to sample selectivity bias. The results show that the estimates are more robust after eliminating sample selectivity bias. The effect of Internet use on civil servants' subjective well-being would be underestimated if the sample selectivity bias is not removed.


Assuntos
Felicidade , Uso da Internet , Masculino , Humanos , Feminino , Análise de Mediação , China , Povo Asiático
13.
Behav Sci (Basel) ; 12(7)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35877291

RESUMO

With societal and technological developments, mobile Internet has become the most popular and widespread means to use the Internet in China. Thus, exploring the relationship between mobile Internet use and the self-rated health and mental health of the Chinese population is of great importance. This study empirically examined the impact of mobile Internet use on residents' health using data from the China Family Panel Studies 2020 and conducted a heterogeneity analysis. The results revealed a significant negative association between mobile Internet use and the self-rated health of the population, but a significant positive association was found relative to their mental health. The results of this analysis passed a robustness test. The results of the heterogeneity analysis showed that mobile Internet use had a more significant association with the health of residents with secondary school education and university education compared to those with primary school education or below and graduate education. Furthermore, this study addresses the endogeneity problem using the propensity-score matching model, which is shown to be better at eliminating sample selectivity bias. If endogeneity is not addressed, the negative association with mobile Internet use on residents' self-rated health will be underestimated and its positive association with their mental health will be overestimated. The Chinese government should issue guidelines on the duration of Internet use, strictly regulate exaggerated and harmful content on mobile network platforms, and strengthen people's online skills through training to improve their digital literacy, especially for rural populations.

14.
Phys Rev Lett ; 128(13): 137201, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426702

RESUMO

The antiferromagnet is considered to be a promising hosting material for the next generation of magnetic storage due to its high stability and stray-field-free property. Understanding the switching properties of the antiferromagnetic (AFM) domain state is critical for developing AFM spintronics. By utilizing the magneto-optical birefringence effect, we experimentally demonstrate the switching rate of the AFM domain can be enhanced by more than 2 orders of magnitude through applying an alternating square-wave field on a single crystalline Fe/CoO bilayer. The observed extraordinary speed can be much faster than that triggered by a constant field with the same amplitude. The effect can be understood as the efficient suppression of the pinning of AFM domain walls by the strong exchange torque triggered by the reversal of the Fe magnetization, as revealed by spin dynamics simulations. Our finding opens up new opportunities to design the antiferromagnet-based spintronic devices utilizing the ferromagnet-antiferromagnet heterostructure.

15.
Nat Commun ; 13(1): 1350, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292656

RESUMO

Magnetic skyrmions are topologically nontrivial spin textures with envisioned applications in energy-efficient magnetic information storage. Toggling the presence of magnetic skyrmions via writing/deleting processes is essential for spintronics applications, which usually require the application of a magnetic field, a gate voltage or an electric current. Here we demonstrate the reversible field-free writing/deleting of skyrmions at room temperature, via hydrogen chemisorption/desorption on the surface of Ni and Co films. Supported by Monte-Carlo simulations, the skyrmion creation/annihilation is attributed to the hydrogen-induced magnetic anisotropy change on ferromagnetic surfaces. We also demonstrate the role of hydrogen and oxygen on magnetic anisotropy and skyrmion deletion on other magnetic surfaces. Our results open up new possibilities for designing skyrmionic and magneto-ionic devices.

16.
Artigo em Inglês | MEDLINE | ID: mdl-35329305

RESUMO

In the context of both rapid technological development and increasing aging, the relationship between technological development and the health of the middle-aged and older population is gradually receiving academic attention. This study empirically examined the health consequences of the Internet for the middle-aged and older population in China using data from the 2018 China Health and Retirement Longitudinal Study. The results indicated that Internet use was effective in improving the self-assessed health and chronic disease status of the middle-aged and older population. However, the effect of Internet use on the improvement of chronic disease conditions in this population was more pronounced than self-assessed health. In the heterogeneity analysis, the effect of Internet use on the health of female and middle-aged adults was more significant than that of male and older adults aged >60 years. This paper also used a propensity score matching model to eliminate the endogeneity problem caused by sample selectivity bias. The results revealed that the propensity score matching model analysis was more robust. Moreover, if sample selectivity bias was not eliminated, the effect of Internet use on the improvement of self-assessed health in the middle-aged and older population would be underestimated, whereas the effect of Internet use on the chronic disease status of the middle-aged and older adults would be overestimated.


Assuntos
Uso da Internet , Aposentadoria , Idoso , China/epidemiologia , Feminino , Nível de Saúde , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
17.
Artigo em Inglês | MEDLINE | ID: mdl-35162345

RESUMO

Given the increasing use of the Internet in China, the relationship between Internet use and population health has been receiving increased academic attention. However, the current literature has not yet reached a unified conclusion; thus, further research is very necessary. This study used the 2018 China Family Panel Studies (CFPS) data to explore the relationship between Internet use and the health of the population and to evaluate the possible heterogeneity of the association between different groups and the mediation path. This study revealed that Internet use has a positive association with the subjective health of the population. The results of the heterogeneity analysis revealed that Internet use is more significantly associated with the health of non-agricultural workers and those with higher education levels than that of agricultural workers and those with lower education levels. Further analysis revealed that health behavior is an important mediator between Internet use and population health. These results remain robust even after using propensity score matching (PSM) to eliminate sample selection bias.


Assuntos
Uso da Internet , Saúde da População , China/epidemiologia , Estudos Transversais , Comportamentos Relacionados com a Saúde , Humanos , Internet
18.
Adv Mater ; 33(23): e2005909, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33938060

RESUMO

Recent experiments show that topological surface states (TSS) in topological insulators (TI) can be exploited to manipulate magnetic ordering in ferromagnets. In principle, TSS should also exist for other topological materials, but it remains unexplored as to whether such states can also be utilized to manipulate ferromagnets. Herein, current-induced magnetization switching enabled by TSS in a non-TI topological material, namely, a topological Dirac semimetal α-Sn, is reported. The experiments use an α-Sn/Ag/CoFeB trilayer structure. The magnetization in the CoFeB layer can be switched by a charge current at room temperature, without an external magnetic field. The data show that the switching is driven by the TSS of the α-Sn layer, rather than spin-orbit coupling in the bulk of the α-Sn layer or current-produced heating. The switching efficiency is as high as in TI systems. This shows that the topological Dirac semimetal α-Sn is as promising as TI materials in terms of spintronic applications.

19.
J Orthop Surg Res ; 16(1): 150, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33610167

RESUMO

OBJECTIVE: We aimed to investigate the therapeutic effects of Moringa oleifera leaf extracts on osteogenic induction of rat bone marrow mesenchymal stem cells (BMSCs) following peroxidative damage and to explore the underlying mechanisms. METHODS: Conditioned medium was used to induce osteogenic differentiation of BMSCs, which were treated with H2O2, Moringa oleifera leaf extracts-containing serum, or the phosphatidyl inositol-3 kinase (PI3K) inhibitor wortmannin, alone or in combination. Cell viability was measured using the MTT assay. Cell cycle was assayed using flow cytometry. Expression levels of Akt, phosphorylated (p)Akt, Foxo1, and cleaved caspase-3 were analyzed using western blot analysis. The mRNA levels of osteogenesis-associated genes, including alkaline phosphatase (ALP), collagen І, osteopontin (OPN), and Runx2, were detected using qRT-PCR. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels, as well as superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and ALP activity were detected using commercially available kits. Osteogenic differentiation capability was determined using alizarin red staining. RESULTS: During osteogenic induction of rat BMSCs, H2O2 reduced cell viability and proliferation, inhibited osteogenesis, increased ROS and MDA levels, and decreased SOD and GSH-PX activity. H2O2 significantly reduced pAkt and Foxo1 expression, and increased cleaved caspase-3 levels in BMSCs. Additional treatments with Moringa oleifera leaf extracts partially reversed the H2O2-induced changes. Wortmannin partially attenuated the effects of Moringa oleifera leaf extracts on protein expression of Foxo1, pAkt, and cleaved caspase-3, as well as mRNA levels of osteogenesis-associated genes. CONCLUSION: Moringa oleifera leaf extracts ameliorate peroxidative damage and enhance osteogenic induction of rat BMSCs by activating the PI3K/Akt/Foxo1 pathway.


Assuntos
Moringa oleifera , Proteínas do Tecido Nervoso/metabolismo , Osteogênese/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Peróxido de Hidrogênio , Masculino , Células-Tronco Mesenquimais , Folhas de Planta , Ratos , Ratos Sprague-Dawley
20.
Neural Regen Res ; 16(8): 1592-1597, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33433489

RESUMO

Cerebrovascular endothelial dysfunction is involved in the progression of leukoaraiosis. Asymmetric dimethylarginine is a competitive inhibitor of nitric oxide, which is highly expressed in patients with leukoaraiosis. Dimethylarginine dimethylaminohydrolase (DDAH) is a hydrolytic enzyme that is primarily responsible for eliminating asymmetric dimethylarginine, and it plays a role in the pathogenesis of cardiovascular and cerebrovascular diseases. The DDAH2 subtype is expressed in organs rich in induced nitric oxide synthase, including the heart, the placenta, and the cerebral endothelium during cerebral ischemia, in the stress state, or under neurotoxicity. Overexpression of the DDAH2 gene can inhibit asymmetric dimethylarginine-induced peripheral circulating endothelial cell dysfunction. However, it is unknown whether this polymorphism regulates plasma asymmetric dimethylarginine levels in patients with leukoaraiosis. In this double-blind study, we recruited 46 patients with leukoaraiosis and 46 healthy, matched controls. Plasma asymmetric dimethylarginine levels were determined using enzyme-linked immunoassays. Genomic DNA was isolated from whole blood samples, and polymerase chain reaction, SmaI restriction enzyme digestion, restriction fragment length polymorphisms, and agarose electrophoresis were used to detect DDAH2 (-449 G/C) gene polymorphisms. The results revealed that 95.65% of leukoaraiosis patients had recessive genetic models (GG and CG), while 89.13% of healthy control subjects had dominant genetic models (CC and CG). There was a significant difference in the genotype composition ratio between leukoaraiosis patients and healthy controls (P = 0.0002). The frequency of G alleles in the leukoaraiosis patients (71.74%) was significantly higher than in healthy controls, whereas the frequency of C alleles was lower (χ2 = 13.9580, P = 0.0002). Furthermore, asymmetric dimethylarginine concentrations in subjects with the GG genotype were significantly higher than in subjects with the CG and CC genotypes (Kruskal-Wallis H = 24.5955, P < 0.0001). In addition, the GG genotype of DDAH2 (-449 G/C) was more common in patients with leukoaraiosis. These findings suggest that the G allele of DDAH2 (-449 G/C) is a risk factor for leukoaraiosis morbidity and is correlated with high levels of asymmetric dimethylarginine. This study was approved by the Institutional Ethics Committee of The 2nd Affiliated Hospital of Harbin Medical University of China (approval No. KY2016-177) on July 28, 2016.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA