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1.
BMC Public Health ; 22(1): 1789, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131316

RESUMO

BACKGROUND: As the number of older people is rapidly growing, prevention, screening, and treatment of mental health problems (including anxiety and depression) in this population increasingly become a heavy burden to individuals, families, and even the whole society. The Kessler-6 screening measure (K6) is an efficient and effective instrument for general mental health problems. However, few studies have examined its measurement invariance across time, which is particularly important in longitudinal studies, such as exploring developmental trajectories of non-specific psychological distress and evaluating the effects of certain interventions. METHODS: The current study investigated the factor structure and the longitudinal measurement invariance of the K6 among a national representative elder sample of China. Longitudinal data in two survey waves (the year 2010, and the year 2014) from the China Family Panel Studies were drawn for secondary data analysis. A total of 3845 participants aged 60 years old and above (52.2% male, mean age = 66.99 years, SD = 5.93 years) responded to both waves of the survey. RESULTS: A comparison of four existing models with confirmatory factor analysis supported a two-factor solution of the K6. A series of multi-group confirmatory factor analyses further indicated that the K6 held strict longitudinal measurement invariance across time. Additionally, the internal consistency indices across time and the stability coefficients over time were acceptable. CONCLUSIONS: The findings further confirmed the psychometric defensibility of the K6 when used in the old Chinese population. The longitudinal measurement invariance justified comparisons of psychological distress scores among different measurement time points.


Assuntos
Estresse Psicológico , Idoso , China/epidemiologia , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Estresse Psicológico/psicologia , Inquéritos e Questionários
2.
Biochem Biophys Res Commun ; 579: 40-46, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34583194

RESUMO

Protein tyrosine phosphatase 1B (PTP1B) is a member of the phosphotyrosine phosphatase family and plays an important role in the signal transduction of diabetes. Inhibition of PTP1B activity can increase insulin sensitivity and reduce blood sugar levels. Therefore, it is urgent to find compounds with novel structures that can inhibit PTP1B. This study designed imidazolidine-2,4-dione derivatives through the computer-aided drug design (CADD) strategy, and the Comp#10 showed outstanding inhibitory ability. (IC50 = 2.07 µM) and selectivity. The inhibitory mechanism at molecular level of Comp#10 on PTP1B was studied by molecular dynamics simulation. The results show that the catalytic region of PTP1B protein is more stable, which makes the catalytic sites unsuitable for exposure. Interestingly, the most obvious changes in the interaction between residues in the P-loop region (such as: His214, Cys215, and Ser216). In short, this study reported for the first time that imidazolidine-2,4-dione derivatives as novel PTP1B inhibitors had good inhibitory activity and selectivity, providing new ideas for the development of small molecule PTP1B inhibitors.


Assuntos
Imidazolidinas/síntese química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Algoritmos , Domínio Catalítico , Química Farmacêutica/métodos , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos , Humanos , Imidazolidinas/química , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Software
3.
BMC Geriatr ; 20(1): 361, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32962656

RESUMO

BACKGROUND: The aging population increases rapidly across the world. Timely and effective screening of their mental-health problems is important to individuals, families, and the whole society. The Kessler-6 screening measure (K6) is a very popular instrument for non-specific psychological distress. However, few studies have focused on the psychometric properties of this instrument in the older population. METHODS: The present study employed Mokken scale analysis to evaluate its dimensionality and structure. This study also used differential item functioning (DIF) to examine whether the same structure existed across sex in a national representative sample of old Chinese people. Data were drawn from a public data set, the 2010 China Family Panel Studies (CFPS2010), and responses from a total of 6450 participants aged 60 years old and above (3136 males and 3314 females) were included in the final analysis. RESULTS: Mokken scale analysis supported the unidimensional structure of the K6. Differential item functioning (DIF) analysis revealed that two of the six items ("Hopeless" and "Everything was an effort") were marked for DIF based on the Chi-square. However, their impacts were negligible in terms of McFadden's pseudo R2. CONCLUSIONS: The K6 demonstrates adequate psychometric properties in the old Chinese population. The sum of all six items can be used as an indicator of non-specific psychological distress. Differences in the indicator across sex should be considered as a real difference in psychological distress between the female and the male.


Assuntos
Povo Asiático , Escalas de Graduação Psiquiátrica/normas , Estresse Psicológico/diagnóstico , Inquéritos e Questionários/normas , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , China/epidemiologia , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Estresse Psicológico/etnologia , Estresse Psicológico/psicologia
4.
Phys Chem Chem Phys ; 21(11): 6186-6197, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30828707

RESUMO

The hydrogen vacancy (VH) is the most common point defect that may lead to optical damage of potassium dihydrogen phosphate (KDP) and its analog ammonium dihydrogen phosphate (ADP), further limiting their practical application in high-power laser systems. In this work, we have grown KDP and ADP crystals by using a rapid growth method, and investigated the physical origin of the different stability of VH as well as the defect-induced electronic structure and optical absorption in KDP and ADP crystals. The inclusion of van der Waals correction to density functional theory calculations is found to have little influence on VH energetics of KDP whereas it largely reduces the charge transition level ε(+/-) of VH by >2 eV in ADP. It is found that hydrogen vacancies mainly contribute to the redshift of the measured absorption edges of both KDP and ADP crystals. Owing to the varied lattice environments and locations, the VH defects exhibit different stability, and electronic and optical properties in KDP and ADP crystals. Notably, the extra optical absorption caused by the positively-charged VH in KDP could be largely reduced by decreasing the defect concentration, whereas ADP exhibits defect-location dependence - the optical damage center of the VH in the NH4+ group could not be eliminated because of electron capture of its neighboring N atoms. The calculation results help us to better understand the origin of laser damage in KDP and ADP crystals.

5.
Appl Opt ; 57(2): 356-361, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29328185

RESUMO

An optical fiber humidity sensor based on an optical Fabry-Perot interferometer is proposed and experimentally demonstrated. The sensor is constructed by a short section of hollow-core fiber coated with a polyimide (PI) film. Taking advantage of the direct response of the PI film, a sensitivity of up to 1.309 nm/%RH can be achieved in the humidity change range from 40% RH to 80% RH. The temperature sensitivity is measured to be 43.57 pm/°C when the temperature changes from 25°C to 55°C. Because of its simple structure, fast response time, convenient production, and good reproducibility, the proposed sensor will be competitive in the field of cultural relic humidity monitoring and pharmaceutical storage.

6.
Chem Pharm Bull (Tokyo) ; 66(4): 358-362, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29607900

RESUMO

Acetohydroxy acid synthase (AHAS; EC 2.2.1.6, also referred to as acetolactate synthase, ALS) has been considered as an attractive target for the design of herbicides. In this work, an optimized pyrazole sulfonamide base scaffold was designed and introduced to derive novel potential AHAS inhibitors by introducing a pyrazole ring in flucarbazone. The results of in vivo herbicidal activity evaluation indicates compound 3b has the most potent activity with rape root length inhibition values of 81% at 100 mg/L, and exhibited the best inhibitory ability against Arabidopsis thaliana AHAS. With molecular docking, compound 3b insert into Arabidopsis thaliana AHAS stably by an H-bond with Arg377 and cation-π interactions with Arg377, Trp574, Tyr579. This study suggests that compound 3b may serve as a potential AHAS inhibitor which can be used as a novel herbicides and provides valuable clues for the further design and optimization of AHAS inhibitors.


Assuntos
Acetolactato Sintase/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Acetolactato Sintase/metabolismo , Arabidopsis/enzimologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química
7.
Bioorg Med Chem ; 24(19): 4652-4659, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27515719

RESUMO

Mitogen activated protein kinase (MAPK) signal transduction pathway has been proved to play an important role in tumorigenesis and cancer development. MEK inhibitor has been demonstrated significant clinical benefit for blocking MAPK pathway activation and possibly could block reactivation of the MAPK pathway at the time of BRAF inhibitor resistance. Twenty N-(benzyloxy)-1,3-diphenyl-1H-pyrazole-4-carboxamide derivatives have been designed and synthesized as MEK inhibitors, and their biological activities were evaluated. Among these compounds, compound 7b showed the most potent inhibitory activity with IC50 of 91nM for MEK1 and GI50 value of 0.26µM for A549 cells. The SAR analysis and docking simulation were performed to provide crucial pharmacophore clues that could be used in further structure optimization.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , MAP Quinase Quinase 1/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/química , Pirazóis/farmacologia , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Relação Quantitativa Estrutura-Atividade
8.
Chem Pharm Bull (Tokyo) ; 64(12): 1755-1762, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27725363

RESUMO

Acetylcholinesterase (AChE) is a key enzyme which present in the central nervous system of living organisms. Organophosphorus pesticides (OPs) that serve as insecticides are AChE inhibitors which have been used widely in agriculture. A series of novel OPs containing pyrazole moiety have been designed and synthesized. The biological evaluation indicated compound 4e appeared 81% larvicidal activity against Plutella xylostella at the concentration of 0.1 mg/L and the inhibition of AChE by compound 4e was distinctly enhanced with the increasing doses. Molecular docking of compound 4e into the three dimensional X-ray structure of the Drosophila melanogaster AChE (DmAChE, PDB code: 1QO9) was carried out utilizating the Discovery Studio (DS), the binding model revealed that the title structure was tightly embedded in the binding sites of DmAChE. Therefore, we suggest that compound 4e may serve as a novel AChE inhibitor that can be utilized as a new insecticidal drug.


Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Organofosfonatos/química , Organofosfonatos/farmacologia , Pirazóis/química , Pirazóis/farmacologia , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Inseticidas/síntese química , Inseticidas/química , Simulação de Acoplamento Molecular , Mariposas/enzimologia , Organofosfonatos/síntese química , Relação Estrutura-Atividade
9.
Opt Express ; 23(18): 23401-13, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26368441

RESUMO

Noncritical phase matching (NCPM) fourth-harmonic-generation (FHG) experiments were conducted on different deuterium content DKDP crystals by adjusting crystal temperature to generate 266 nm deep UV laser. Specially, near room temperature NCPM is realized in extremely high deuterium content DKDP crystal at 38.6 °C, which is the lowest temperature to the best of our knowledge. NCPM temperature of DKDP crystals in 60-100% deuterium content range and 1050-1070 nm wavelength range are determined by a linear relationship according to the experimental and calculated results. Angular tuning properties are independent with deuterium content in medium and higher deuterium content DKDP crystals. All of these results will provide good references for future FHG applications of 1 µm laser with DKDP crystals.

10.
J Comp Eff Res ; 13(5): e230085, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38567965

RESUMO

Aim: The first objective is to compare the performance of two-stage residual inclusion (2SRI), two-stage least square (2SLS) with the multivariable generalized linear model (GLM) in terms of the reducing unmeasured confounding bias. The second objective is to demonstrate the ability of 2SRI and 2SPS in alleviating unmeasured confounding when noncollapsibility exists. Materials & methods: This study comprises a simulation study and an empirical example from a real-world UK population health dataset (Clinical Practice Research Datalink). The instrumental variable (IV) used is based on physicians' prescribing preferences (defined by prescribing history). Results: The percent bias of 2SRI in terms of treatment effect estimates to be lower than GLM and 2SPS and was less than 15% in most scenarios. Further, 2SRI was found to be robust to mild noncollapsibility with the percent bias less than 50%. As the level of unmeasured confounding increased, the ability to alleviate the noncollapsibility decreased. Strong IVs tended to be more robust to noncollapsibility than weak IVs. Conclusion: 2SRI tends to be less biased than GLM and 2SPS in terms of estimating treatment effect. It can be robust to noncollapsibility in the case of the mild unmeasured confounding effect.


Assuntos
Fatores de Confusão Epidemiológicos , Padrões de Prática Médica , Humanos , Padrões de Prática Médica/estatística & dados numéricos , Viés , Modelos Lineares , Análise dos Mínimos Quadrados , Reino Unido , Simulação por Computador
11.
J Comp Eff Res ; 13(5): e230044, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38567966

RESUMO

Aim: This simulation study is to assess the utility of physician's prescribing preference (PPP) as an instrumental variable for moderate and smaller sample sizes. Materials & methods: We designed a simulation study to imitate a comparative effectiveness research under different sample sizes. We compare the performance of instrumental variable (IV) and non-IV approaches using two-stage least squares (2SLS) and ordinary least squares (OLS) methods, respectively. Further, we test the performance of different forms of proxies for PPP as an IV. Results: The percent bias of 2SLS is around approximately 20%, while the percent bias of OLS is close to 60%. The sample size is not associated with the level of bias for the PPP IV approach. Conclusion: Irrespective of sample size, the PPP IV approach leads to less biased estimates of treatment effectiveness than OLS adjusting for known confounding only. Particularly for smaller sample sizes, we recommend constructing PPP from long prescribing histories to improve statistical power.


Assuntos
Pesquisa Comparativa da Efetividade , Simulação por Computador , Padrões de Prática Médica , Humanos , Pesquisa Comparativa da Efetividade/métodos , Tamanho da Amostra , Padrões de Prática Médica/estatística & dados numéricos , Análise dos Mínimos Quadrados , Viés
12.
Drug Alcohol Rev ; 43(5): 1183-1193, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38653552

RESUMO

INTRODUCTION: We assessed the prevalence of prescribing of certain medications for alcohol dependence and the extent of any inequalities in receiving prescriptions for individuals with such a diagnosis. Further, we compared the effectiveness of two of the most prescribed medications (acamprosate and disulfiram) for alcohol dependence and assessed whether there is inequality in prescribing either of them. METHODS: We used a nationwide dataset on prescriptions and hospitalisations in Scotland, UK (N = 19,748). We calculated the percentage of patients receiving alcohol dependence prescriptions after discharge, both overall and by socio-economic groups. Binary logistic regressions were used to assess the odds of receiving any alcohol-dependence prescription and the comparative odds of receiving acamprosate or disulfiram. Comparative effectiveness in avoiding future alcohol-related hospitalisations (N = 11,239) was assessed using Cox modelling with statistical adjustment for potential confounding. RESULTS: Upto 7% of hospitalised individuals for alcohol use disorder received prescriptions for alcohol dependence after being discharged. Least deprived socio-economic groups had relatively more individuals receiving prescriptions. Inequalities in prescribing for alcohol dependence existed, especially across sex and comorbidities: males had 12% (odds ratio [OR] 0.88, 95% confidence interval [CI] 0.81-0.96) and those with a history of mental health hospitalisations had 10% (OR 0.90, 95% CI 0.82-0.98) lower odds of receiving prescriptions after an alcohol-related hospitalisation. Prescribing disulfiram was superior to prescribing acamprosate in preventing alcohol-related hospitalisations (hazard ratio ranged between 0.60 and 0.81 across analyses). Disulfiram was relatively less likely prescribed to those from more deprived areas. DISCUSSION AND CONCLUSIONS: Inequalities in prescribing for alcohol dependence exists in Scotland with lower prescribing to men and disulfiram prescribed more to those from least deprived areas.


Assuntos
Acamprosato , Dissuasores de Álcool , Alcoolismo , Dissulfiram , Taurina , Humanos , Masculino , Acamprosato/uso terapêutico , Dissulfiram/uso terapêutico , Feminino , Alcoolismo/tratamento farmacológico , Alcoolismo/epidemiologia , Dissuasores de Álcool/uso terapêutico , Adulto , Pessoa de Meia-Idade , Taurina/uso terapêutico , Taurina/análogos & derivados , Escócia/epidemiologia , Estudos de Coortes , Fatores Socioeconômicos , Hospitalização/estatística & dados numéricos , Adulto Jovem , Disparidades em Assistência à Saúde , Reino Unido/epidemiologia , Idoso , Resultado do Tratamento
13.
Int J Ment Health Addict ; : 1-16, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37363757

RESUMO

In 2018, Scotland introduced a minimum unit price (MUP) for alcohol to reduce alcohol-related harms. We aimed to study the association between MUP introduction and the volume of prescriptions to treat alcohol dependence, and volume of new patients receiving such prescriptions. We also examined whether effects varied across different socio-economic groups. A controlled interrupted time series was used to examine variations of our two outcomes. The same prescriptions in England and prescriptions for methadone in Scotland were used as controls. There was no evidence of an association between MUP implementation and the volume of prescriptions for alcohol dependence (immediate change: 2.74%, 95% CI: -0.068 0.014; slope change: 0% 95%CI: -0.001 0.000). A small, significant increase in slope in number of new patients receiving prescriptions was observed (0.2% 95%CI: 0.001 0.003). However, no significant results were confirmed after robustness checks. We found also no variation across different socioeconomic groups. Supplementary Information: The online version contains supplementary material available at 10.1007/s11469-023-01070-6.

14.
Psychol Rep ; 110(1): 263-75, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22489392

RESUMO

The present study used a sample of Chinese adolescents and validated a short-form of the Egna Minnen Beträffande Uppfostran: One's Memories of Upbringing (s-EMBU) assessing perceived parental rearing styles. A Chinese revision of the s-EMBU by the authors was administered to a total of 779 high school students, ages 11 to 19 years. Exploratory factor analysis with half of the sample yielded a three-factor solution of Rejection, Emotional Warmth, and Overprotection, accounting for 47.1% of the total variance onthe father form and 48.8% of the total variance on the mother form. Then, confirmatory factor analysis indicated a good fit of the three-factor model to the data in the other half of the sample. The three subscales consisted of 6, 6, and 7 items, respectively. Scores on these subscales had Cronbach alphas ranging from .71 to .81, indicating adequate internal consistency. These psychometric properties suggest its applicability for research with Chinese adolescents.


Assuntos
Educação Infantil/psicologia , Relações Pais-Filho , Poder Familiar/psicologia , Inquéritos e Questionários , Adolescente , Adulto , Atitude , Criança , China , Análise Fatorial , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Adulto Jovem
15.
J Clin Epidemiol ; 148: 74-80, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35447357

RESUMO

OBJECTIVES: To review comparative effectiveness research (CER) using physician's prescribing preference as an instrumental variable (PPP IV) in pharmacoepidemiology and to review methodological studies that use simulation to evaluate the performance of PPP IV in CER. STUDY DESIGN AND SETTING: We conducted a review of CER using PPP IV and studies evaluating the use of PPP IV by using simulation methods. We searched Ovid, PubMed, and Google Scholar databases from 2005 to 2020. RESULTS: We identified six simulation studies and 18 CER studies. The simulation studies explored the most suitable ways for using PPP IV in different settings (outcome types, sample size, and the prevalence of outcomes) which can be useful guidance for using PPP IV in CER. The CER studies identified show heterogeneity in terms of validation assumptions, estimation methods, and sample size. Not all applied studies used the methodological insights from the simulation studies. However, they all concluded that PPP is a valid IV. CONCLUSION: Future CER should consider a range of methodological issues to improve the validity of findings when using PPP IV. Specifically, studies should consider the impact of a different choice of statistical methods, forms of proxy for measuring preference, time-varying exposures, and the type of outcome.


Assuntos
Pesquisa Comparativa da Efetividade , Médicos , Humanos , Padrões de Prática Médica , Farmacoepidemiologia/métodos , Simulação por Computador
16.
Behav Sci (Basel) ; 12(12)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36546959

RESUMO

Previous studies have explored the differences in moral judgments under normal situations and acute stress using the Trier Social Stress Test (TSST). The present study examined whether anticipatory stress (i.e., induced by an anticipated speech) could elicit similar effects and further explored the mediation of emotional responses between acute stress and moral judgments with a process-dissociation approach. Fifty-three undergraduate students (20 males and 33 females) were randomly assigned to the stress and control groups. In the first stage, they were instructed to prepare a public speech (the stress group) or just recall events during the previous vacation (the control group). In the second stage, they reported emotional valence and arousal for each moral dilemma in a set of 12 moral dilemmas, followed by judgments on moral acceptability of the agent's action. The manipulation check confirmed that anticipatory stress was reliably induced, as indicated in both self-reported and physiological data. The traditional dilemma analysis revealed that participants in the stress group would make fewer utilitarian judgments than those in the control group. The process dissociation (PD) analyses further revealed that the stress group exhibited higher deontological inclinations than the control group, but no significant differences in utilitarian inclinations. Emotional valence played a mediating role in the association between stress and deontological inclinations. To sum up, our study extended the investigation of the relationship between acute stress and moral judgment to anticipatory stress, clarified its distinct impact on deontological and utilitarian inclinations, and revealed the mediating effect of emotional valence.

17.
Light Sci Appl ; 11(1): 241, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906198

RESUMO

In this review, we introduce the progress in the growth of large-aperture DKDP crystals and some aspects of crystal quality including determination of deuterium content, homogeneity of deuterium distribution, residual strains, nonlinear absorption, and laser-induced damage resistance for its application in high power laser system. Large-aperture high-quality DKDP crystal with deuteration level of 70% has been successfully grown by the traditional method, which can fabricate the large single-crystal optics with the size exceeding 400 mm. Neutron diffraction technique is an efficient method to research the deuterium content and 3D residual strains in single crystals. More efforts have been paid in the processes of purity of raw materials, continuous filtration technology, thermal annealing and laser conditioning for increasing the laser-induced damage threshold (LIDT) and these processes enable the currently grown crystals to meet the specifications of the laser system for inertial confinement fusion (ICF), although the laser damage mechanism and laser conditioning mechanism are still not well understood. The advancements on growth of large-aperture high-quality DKDP crystal would support the development of ICF in China.

18.
J Mater Chem B ; 9(1): 80-84, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33313613

RESUMO

Specific and expeditious identification and enrichment of target proteins in living cells is often a challenging task. The hexahistidine (6His) tag is frequently used to label artificially engineered proteins produced in prokaryotic or eukaryotic cells. Utilizing the interaction between 6His-tag and nitrilotriacetic acid (NTA) mediated by divalent metal ions (Ni2+, Cu2+, Zn2+ or Co2+), we designed and synthesized a series of Nap-G/Biotin/ANA-FFpYGK-NTA probes that, assisted by alkaline phosphatase (ALP), self-assemble into nanofibers. The probe consists of an NTA group that specifically binds to 6His-tag, an FFpY group that promotes self-assembly facilitated by ALP, and a hydrophobic (Nap-G/ANA/Biotin) capping group for various applications. We demonstrate that the ANA-FFpYGK-NTA(Ni2+) nanofibers are fit for real-time tracking of His-tagged protein in living cells, and the Biotin-FFpYGK-NTA(Ni2+) nanofibers are for isolating His-tagged proteins and other proteins that they interact with.


Assuntos
Quelantes/metabolismo , Citoplasma/metabolismo , Histidina/metabolismo , Nanofibras , Ácido Nitrilotriacético/metabolismo , Oligopeptídeos/metabolismo , Quelantes/análise , Citoplasma/química , Corantes Fluorescentes/análise , Corantes Fluorescentes/metabolismo , Histidina/análise , Humanos , Células MCF-7 , Nanofibras/análise , Ácido Nitrilotriacético/análise , Oligopeptídeos/análise
19.
Chem Commun (Camb) ; 57(6): 797-800, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33355564

RESUMO

Caspase-3/8 are key members of the cysteine-aspartyl protease family with pivotal roles in apoptosis. We have designed and synthesized self-assembling probes, Nap-GFFpYDEVD-AFC and Nap-GFFpYIETD-AFC, with fluorescence 'turn-on' properties for real-time monitoring of Caspase-3/8 activity in living cells.


Assuntos
Caspase 3/análise , Caspase 8/análise , Ensaios Enzimáticos/métodos , Corantes Fluorescentes/química , Nanofibras/química , Caspase 3/metabolismo , Caspase 8/metabolismo , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Microscopia Confocal , Estrutura Molecular , Fatores de Tempo
20.
Nat Commun ; 12(1): 2587, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972537

RESUMO

Host cells use several anti-bacterial pathways to defend against pathogens. Here, using a uropathogenic Escherichia coli (UPEC) infection model, we demonstrate that bacterial infection upregulates RhoB, which subsequently promotes intracellular bacteria clearance by inducing LC3 lipidation and autophagosome formation. RhoB binds with Beclin 1 through its residues at 118 to 140 and the Beclin 1 CCD domain, with RhoB Arg133 being the key binding residue. Binding of RhoB to Beclin 1 enhances the Hsp90-Beclin 1 interaction, preventing Beclin 1 degradation. RhoB also directly interacts with Hsp90, maintaining RhoB levels. UPEC infections increase RhoB, Beclin 1 and LC3 levels in bladder epithelium in vivo, whereas Beclin 1 and LC3 levels as well as UPEC clearance are substantially reduced in RhoB+/- and RhoB-/- mice upon infection. We conclude that when stimulated by UPEC infections, host cells promote UPEC clearance through the RhoB-Beclin 1-HSP90 complex, indicating RhoB may be a useful target when developing UPEC treatment strategies.


Assuntos
Autofagossomos/metabolismo , Proteína Beclina-1/metabolismo , Infecções por Escherichia coli/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Infecções Urinárias/metabolismo , Escherichia coli Uropatogênica/crescimento & desenvolvimento , Proteína rhoB de Ligação ao GTP/metabolismo , Animais , Autofagossomos/genética , Autofagossomos/ultraestrutura , Proteína Beclina-1/genética , Linhagem Celular , Epitélio/metabolismo , Epitélio/microbiologia , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Feminino , Técnicas de Silenciamento de Genes , Proteínas de Choque Térmico HSP90/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/metabolismo , Ligação Proteica , Estabilidade Proteica , RNA Interferente Pequeno , Proteínas Recombinantes , Bexiga Urinária/metabolismo , Bexiga Urinária/microbiologia , Infecções Urinárias/genética , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/patogenicidade , Proteína rhoB de Ligação ao GTP/genética
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