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1.
Psychosom Med ; 83(4): 380-386, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33790199

RESUMO

OBJECTIVE: Primary care physicians (PCPs) play a key role in responding to the COVID-19 epidemic. The objective of this study was to explore the influencing factors associated with self-reported psychological distress among a sample of PCPs in China in relation to COVID-19. METHODS: An online survey was distributed to a sample of PCPs in Chengdu city between February 10 and February 13, 2020. The survey consisted of three sections: demographic characteristics, COVID-19-related questions, and the General Health Questionnaire-12 (GHQ-12). After 5 months, a follow-up survey investigating the change of the GHQ-12 was conducted. RESULTS: A total of 712 PCPs completed the baseline survey (11.8% of those invited), 55.6% were female and 74.4% were aged between 30 and 49 years. High levels of psychological distress (GHQ-12 ≥3) were observed in 29.2% and were associated with low preparedness, high work impact, working with infected residents, personal life impact, and concerns, as well as older age and being married (p values < .05). Logistic regression analysis showed that psychological distress was associated with low preparedness (odds ratio [OR] = 0.91, 95% confidence interval [CI] = 0.87-0.96), high work impact (OR = 1.11, 95% CI = 1.03-1.20), personal life impact (OR = 1.12, 95% CI = 1.07-1.17), and safety-related concerns (OR = 1.09, 95% CI = 1.02-1.16). At the 5-month assessment point, high psychological distress was less frequent (21.8%). CONCLUSIONS: COVID-19 has resulted in high levels of distress in approximately 30% of PCPs in China. Factors associated with high psychological distress levels include low preparedness and high levels of work impact, personal life impact, and concerns. These findings highlight the importance of enhancing psychological health throughout the course of infectious pandemics.


Assuntos
COVID-19/psicologia , Estresse Ocupacional/etiologia , Médicos de Atenção Primária/psicologia , Angústia Psicológica , Adulto , COVID-19/epidemiologia , China/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estresse Ocupacional/epidemiologia , Pandemias/estatística & dados numéricos , Médicos de Atenção Primária/estatística & dados numéricos , Fatores de Risco , Inquéritos e Questionários
2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 33(2): 362-7, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-29708674

RESUMO

Diffusion tensor imaging(DTI)is a rapid development technology in recent years of magnetic resonance imaging.The diffusion tensor interpolation is a very important procedure in DTI image processing.The traditional spectral quaternion interpolation method revises the direction of the interpolation tensor and can preserve tensors anisotropy,but the method does not revise the size of tensors.The present study puts forward an improved spectral quaternion interpolation method on the basis of traditional spectral quaternion interpolation.Firstly,we decomposed diffusion tensors with the direction of tensors being represented by quaternion.Then we revised the size and direction of the tensor respectively according to different situations.Finally,we acquired the tensor of interpolation point by calculating the weighted average.We compared the improved method with the spectral quaternion method and the Log-Euclidean method by the simulation data and the real data.The results showed that the improved method could not only keep the monotonicity of the fractional anisotropy(FA)and the determinant of tensors,but also preserve the tensor anisotropy at the same time.In conclusion,the improved method provides a kind of important interpolation method for diffusion tensor image processing.


Assuntos
Imagem de Tensor de Difusão , Anisotropia , Imagem de Difusão por Ressonância Magnética , Humanos , Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador
4.
Eur J Med Chem ; 276: 116635, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38964258

RESUMO

Fifteen betulonic/betulinic acid conjugated with nucleoside derivatives were synthesized to enhance antitumor potency and water solubility. Among these, the methylated betulonic acid-azidothymidine compound (8c) exhibited a broad-spectrum of antitumor activity against three tested tumor cell lines, including SMMC-7721 (IC50 = 5.02 µM), KYSE-150 (IC50 = 5.68 µM), and SW620 (IC50 = 4.61 µM) and along with lower toxicity (TC50 > 100 µM) estimated by zebrafish embryos assay. Compared to betulinic acid (<0.05 µg/mL), compound 8c showed approximately 40-fold higher water solubility (1.98 µg/mL). In SMMC-7721 cells, compound 8c induced autophagy and apoptosis as its concentration increased. Transcriptomic sequencing analysis was used to understand the potential impacts of the underlying mechanism of 8c on SMMC-7721 cells. Transcriptomic studies indicated that compound 8c could activate autophagy by inhibiting the PI3K/AKT pathway in SMMC-7721 cells. Furthermore, in the xenograft mice study, compound 8c significantly slowed down the tumor growth, as potent as paclitaxel treated group. In conclusion, methylated betulonic acid-azidothymidine compound (8c) not only increases water solubility, but also enhances the potency against hepatocellular carcinoma cells by inducing autophagy and apoptosis, and suppressing the PI3K/Akt/mTOR signaling pathway.

5.
Polymers (Basel) ; 15(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37376350

RESUMO

In this study, Sylgard 184 silicone rubber (SylSR) matrix composites with shear thickening fluid (STF) microcapsules (SylSR/STF) were fabricated. Their mechanical behaviors were characterized by dynamic thermo-mechanical analysis (DMA) and quasi-static compression. Their damping properties increased with the addition ofSTF into the SR in DMA tests and the SylSR/STF composites presented decreased stiffness and an obvious positive strain rate effect in the quasi-static compression test. Moreover, the impact resistance behavior of the SylSR/STF composites was tested by the drop hammer impact test. The addition of STF enhanced the impact protective performance of silicone rubber, and the impact resistance increased with the increase of STF content, which should be ascribed to the shear thickening and energy absorption of STF microcapsules in the composites. Meanwhile, in another matrix, hot vulcanized silicone rubber (HTVSR) with a mechanical strength higher than Sylgard 184, the impact resistance capacity of its composite with STF (HTVSR/STF) was also examined by the drop hammer impact test. It is interesting to note that the strength of the SR matrix obviously influenced the enhancement effect of STF on the impact resistance of SR. The stronger the strength of SR, the better the effect of STF on improving the impact protective performance of SR. This study not only provides a new method for packaging STF and improving the impact resistance behavior of SR, but is also beneficial for the design of STF-related protective functional materials and structures.

6.
Neuropsychiatr Dis Treat ; 19: 2149-2169, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37867932

RESUMO

Background: Subthreshold depression (StD) is considered to be the "precursor" stage of major depressive disorder (MDD), which could cause higher risk of suicide, disease burden and functional impairment. There have been various non-pharmacological interventions for StD. However, the comparison of their effectiveness still lacks sufficient evidence. We performed a systematic review and network meta-analysis to evaluate and rank the efficacy of multiple non-pharmacological interventions targeting StD. Methods: We conducted a thorough search across various databases including PubMed, Medline, Embase, Web of Science and PsycINFO from inception to December 2022. All included studies were randomized controlled trials (RCTs) of non-pharmacological interventions for patients with StD compared with control group (CG). Several universal scales for measuring depression severity were used as efficacy outcomes. The surface under the cumulative ranking curve (SUCRA) was used to separately rank each intervention using the "Stata 17.0" software. Results: A total of thirty-six trials were included, involving twenty-eight interventions and 7417 participants. The research found that most non-pharmacological interventions were superior to controls for StD. In each outcome evaluation by different scales for measuring depression, psychotherapy always ranked first in terms of treatment effectiveness, especially Problem-solving Therapy (PST), Behavioral Activation Therapy (BAT), Cognitive Behavioral Therapy (CBT)/Internet-based CBT (I-CBT)/Telephone-based CBT (T-CBT). Since different groups could not be directly compared, the total optimal intervention could not be determined. Conclusion: Here, we show that psychotherapy may be the better choice for the treatment of StD. This study provides some evidence on StD management selection for clinical workers. However, to establish its intervention effect more conclusively, the content, format and operators of psychotherapy still require extensive exploration to conduct more effective, convenient and cost-effective implementation in primary healthcare. Notably, further research is also urgently needed to find the biological and neural mechanisms of StD by examining whether psychotherapy alters neuroplasticity in patients with StD.

7.
RSC Adv ; 13(41): 28371-28381, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37766932

RESUMO

Thermal kinetic parameters are important for establishing the relationship between the aging process, time, and temperature, which would help predict the thermal aging lifetime and stability in the application of polymer materials. We developed a multi-channel in situ detecting device, which provided an efficient method for IR spectrum measurement. The thermal aging process of polyvinyl butyral (PVB) at several constant temperatures (100 °C, 110 °C, 120 °C, 135 °C, and 150 °C) had been studied by the multi-channel in situ infrared reaction device. The kinetic parameters (Eα) were calculated from the absorbance intensity of -C-O-, -C[double bond, length as m-dash]O, -CH3, and -OH. The -OH proved to be the active site of PVB during thermal aging, and a possible thermal aging mechanism of PVB was proposed. We proved the method using a combination of a multi-channel in situ reaction device and FTIR was suitable to study the aging mechanism and kinetics of polymers.

8.
J Hepatobiliary Pancreat Sci ; 28(5): 397-408, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32897643

RESUMO

BACKGROUND/PURPOSE: Delayed gastric emptying (DGE) is one of the most common complications after pancreaticoduodenectomy (PD). The aim of the present meta-analysis was to evaluate the effect of Billroth-II(B-II) versus Roux-en-Y (R-Y) reconstruction for gastrojejunostomy on DGE after PD. METHODS: A systematic literature search was performed using the electronic database MEDLINE (via PubMed and OVID), EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) of the Cochrane Library to select pertinent randomized controlled trials (RCTs) on this topic from January 1990 to January 2020. The primary outcome was identified as postoperative DGE. Subgroup analysis was established to compare the incidence of grade B and C DGE. Software Revman 5.3 was used for the statistical analysis, summary statistics were calculated using fixed effect model or random effect model. RESULTS: Five RCTs including a total of 612 patients were eligible for this meta-analysis. The incidence of grade B and C DGE was significantly lower with the B-II reconstruction than with the R-Y reconstruction (8.0% vs. 14.8%, OR = 0.49, 95% CI: 0.26-0.95, P = 0.03) and the B-II reconstruction took a shorter operation time (WMD=-7.18, 95% CI: [-13.09, -1.27], P = 0,02). No statistically significant difference was found between the two reconstruction methods in terms of the incidence of postoperative pancreatic fistula (POPF), bile leak, intra-abdominal abscess, postoperative pneumonia and the length of postoperative hospital stay. CONCLUSIONS: B-II reconstruction after PD has a lower incidence of grade B and C DGE and shorter operation time compared with R-Y reconstruction.


Assuntos
Derivação Gástrica , Gastroparesia , Anastomose em-Y de Roux/efeitos adversos , Derivação Gástrica/efeitos adversos , Esvaziamento Gástrico , Gastroenterostomia/efeitos adversos , Gastroparesia/epidemiologia , Gastroparesia/etiologia , Humanos , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 240: 118577, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32574988

RESUMO

The thermal decomposition process of 2,6-diamino-3,5-dinitropyrazine-1-oxide(LLM-105)under several constant temperatures (100 °C, 115 °C, 130 °C, and 145 °C) have been studied by a multi-channel in-situ reaction system. Almost 1000 spectra were obtained within 24 days by Fourier-transform infrared spectroscopy (FT-IR). The thermal decomposition activation energies (Eα) of C-NH2 and C-NO2 in LLM-105 were calculated by the Arrhenius equation to be 89.65 and 145.09 kJ mol-1, respectively. The thermal decomposition process of LLM-105 under long-term constant temperature is divided into two paths: intramolecular H-transfer and C-NO2 partition. It is feasible to study the aging process of materials using a combination of a multi-channel in-situ reaction system and FT-IR, which can effectively monitor the evolution of structure.

10.
Materials (Basel) ; 11(10)2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30340381

RESUMO

Coalbed methane (CBM) is a kind of unconventional gas. CBM often contains a great deal of air when it comes out of the well. So, it must be condensed and purified before it can be applied. In this paper, raw clinoptilolite (Cp) was treated with grinding, gravimetric concentration, and ion-exchange using different aqueous solutions of salts. Then, the modified Cp powder was prepared into particles as adsorbents. Then, the adsorbents were used for nitrogen/methane separation in pressure swing adsorption (PSA) at the same condition of 0.2 MPa and 298 K. Research results indicated that there were micropores and lots of mesopores in the Cp, and the pores were mainly slit holes formed by sheet stacking. The adsorbents of NH4-Cp, Cs-Cp, and Cu-Cp showed good equilibrium selectivity for CH4, and the equilibrium separation factors of CH4 and N2 were 2.56, 2.31, and 1.95, respectively. The adsorbents of Na-Cp and Ag-Cp showed good equilibrium selectivity for N2, and the equilibrium separation factors of N2 and CH4 were 7.25 and 6.53, respectively. Consequently, the adsorbent of Na-Cp was suitable for nitrogen/methane mixture separation, which could make the concentration of methane concentrated from 19.7% to 30.72%.

11.
Front Chem ; 6: 633, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619837

RESUMO

Clinoptilolite is a widely distributed tectosilicate, mainly composed of Al2O3, SiO2 with exchangeable cations such as Ca, K, Mg, and Na. In this research, raw clinoptilolite was ground, gravimetrically concentrated and ion-exchanged using different concentrations of NaCl solution. Then the modified clinoptilolite powder was formulated into particles as adsorbents. The adsorbents were applied to CH4 separation in coal bed gas. The raw and modified clinoptilolites were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), atomic emission spectrometer (ICP-AES), Fourier transform infrared spectrometer (FTIR), and Brunauer Emmett Teller (BET) specific surface area. The CH4 absorptivity by raw and modified clinoptilolites was evaluated using pressure swing adsorption (PSA) to assess the CH4 separation ability. The results indicated that the ion-exchanged clinoptilolite using 0.2 mol/L NaCl solution was found to be promising for the kinetic PSA separation of CH4/N2, giving a better absorptivity for CH4 separation under different influence factors. Based on the simulated static experiments, it was indicated that both CH4 and N2 were capable of diffusing into clinoptilolite while N2 adsorption by clinoptilolite was excellent. The experiment results also indicated that ion-exchanged clinoptilolite using a 0.2 mol/L NaCl solution was the optimal adsorbent for separating CH4/N2 at the low pressure condition. From the simulated dynamic experiments, the ion-exchanged clinoptilolite using a 0.2 mol/L NaCl solution as a potential sorbent in kinetic PSA processes for N2/CH4 separation, exhibited the best performance at 648 K under 0.2 MPa within 28 min, in comparison to the raw clinoptilolite and clinoptilolite under other modification conditions. In the next phase of research, the modified clinoptilolite will be tested for CH4 separation in real coal bed gas.

12.
Protein Pept Lett ; 24(6): 489-494, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28260502

RESUMO

BACKGROUND: BAFF and APRIL are members of TNF superfamily. They play vital roles in the pathogenesis of autoimmune diseases. BCMA, a receptor, shows higher affinity for APRIL than for BAFF. Previous studies found that ligand binding specificity of BCMA may be determined by sequence outside DxL motif. OBJECTIVE: Investigate the contribution of a segment outside the DxL motif of BCMA for binding with ligands. METHOD: In this study, the conservative region of BCMA was divided into two segments: BCMA1 (NEYFDSLLHACIPC), a segment of the DXL motif and BCMA2 (QLRCSSNTPPLT), a segment outside of the DXL motif. Two peptides corresponding to the two segments were synthesized and their contribution to the ligands binding were detected by competitive ELISA. BCMA1-Fc fusion protein was also constructed, purified and analyzed by indirect and competitive ELISA. RESULTS: BCMA2 had no inhibiting effect on the interaction of BCMA-Fc and BCMA1-Fc with BAFF, but, it inhibited 22.5% and 15.2% of the interaction of BCMA-Fc and BCMA1-Fc with mAPRIL respectively. The binding rates of BCMA1-Fc for BAFF were 91.7%, but 80.6% for mAPRIL, suggesting that BCMA1-Fc without BCMA2, bound BAFF well and less efficiently to mAPRIL. CONCLUSION: These results suggest that BCMA2 outside of the conservative DxL motif of BCMA may play an important role in the binding selectivity to its ligands.


Assuntos
Fator Ativador de Células B/genética , Antígeno de Maturação de Linfócitos B/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Motivos de Aminoácidos , Fator Ativador de Células B/química , Antígeno de Maturação de Linfócitos B/química , Sequência Conservada/genética , Ensaio de Imunoadsorção Enzimática , Humanos , Ligantes , Ligação Proteica , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/química
13.
Ultrason Sonochem ; 21(4): 1349-57, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24613468

RESUMO

To improve the safety of sensitive explosive HMX while maintaining explosion performance, a moderately powerful but insensitive explosive TATB was used to coat HMX microparticles via a facile ultrasonic method. By using Estane as surface modifier and nano-sized TATB as the shell layer, the HMX@TATB core-shell microparticles with a monodisperse size and compact shell structure were successfully constructed. Both scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) results confirmed the formation of perfect core-shell structured composites. Based on a systematic and comparative study of the effect of experimental conditions, a possible formation mechanism of core-shell structure was proposed in detail. Moreover, the perfect core-shell HMX@TATB microparticles exhibited a unique thermal behavior and significantly improved mechanical sensitivity compared with that of the physical mixture.

14.
Huan Jing Ke Xue ; 27(8): 1603-7, 2006 Aug.
Artigo em Zh | MEDLINE | ID: mdl-17111619

RESUMO

Some organic matter that have aromatic structure similar as humic acid are selected to conduct chlorination test, determined the formation of HAAs and THMs of tested matters, researched the relationship of the chemical structure of DBPFP with DBPs formation characteristics. The results indicated that: (1) The sequence of HAAs formation activity is p-Hydroxybenzoic acid > p-Aminoacetophenone > o-Benzenediol > m-Benzenediol; and THMs' s is m-Benzenediol > p-Aminoacetophenone > 2-Hydroxy-p-aminoacetophenone > p-Hydroxybenzoic acid. (2) The sequence of earlier chlorination reaction rate of HAAs is m-Benzenediol > p-Aminoacetophenone > p-Hydroxybenzoic acid > o-Benzenediol; and THMs' s is p-Hydroxybenzoic acid > 2-Hydroxy-p-aminoacetophenone > m-Benzenediol > p-Aminoacetophenone. (3) The substances that having the substituent group structure of para and ortho position are mostly format HAAs, and one's of having meta position are mostly format THMs. (4) On the benzene ring, hydroxyl group has the highest activity of forming DBPs, and the second is ketone group; amino-group is play a part of auxiliary forming para, ortho or meta position structure mainly; aldehyde and carboxyl group are inert function group; the function of methyl group is remain to be determined.


Assuntos
Compostos Clorados/química , Cloro/química , Hidrocarbonetos Aromáticos/química , Hidrocarbonetos Halogenados/química , Ácido Acético/análise , Ácido Acético/química , Compostos Clorados/análise , Desinfetantes/química , Monitoramento Ambiental , Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos Halogenados/análise , Estrutura Molecular , Trialometanos/análise , Trialometanos/química , Purificação da Água
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