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1.
Nature ; 629(8012): 597-602, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658762

RESUMO

Hydroformylation is an industrial process for the production of aldehydes from alkenes1,2. Regioselective hydroformylation of propene to high-value n-butanal is particularly important, owing to a wide range of bulk applications of n-butanal in the manufacture of various necessities in human daily life3. Supported rhodium (Rh) hydroformylation catalysts, which often excel in catalyst recyclability, ease of separation and adaptability for continuous-flow processes, have been greatly exploited4. Nonetheless, they usually consist of rotationally flexible and sterically unconstrained Rh hydride dicarbonyl centres, only affording limited regioselectivity to n-butanal5-8. Here we show that proper encapsulation of Rh species comprising Rh(I)-gem-dicarbonyl centres within a MEL zeolite framework allows the breaking of the above model. The optimized catalyst exhibits more than 99% regioselectivity to n-butanal and more than 99% selectivity to aldehydes at a product formation turnover frequency (TOF) of 6,500 h-1, surpassing the performance of all heterogeneous and most homogeneous catalysts developed so far. Our comprehensive studies show that the zeolite framework can act as a scaffold to steer the reaction pathway of the intermediates confined in the space between the zeolite framework and Rh centres towards the exclusive formation of n-butanal.


Assuntos
Aldeídos , Alcenos , Ródio , Zeolitas , Catálise , Ródio/química , Zeolitas/química , Alcenos/química , Aldeídos/química , Estereoisomerismo
2.
J Inflamm Res ; 16: 4833-4843, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901384

RESUMO

Introduction: Ferroptosis, a crucial type of programmed cell death, is directly linked to various cardiac disorders. However, the contribution of ferroptosis-related genes (FRGs) to Takotsubo syndrome (TTS) has not been completely understood. Purpose: The objective of this study was to investigate the relationship between the FRGs and TTS. Methods: TTS rat models were established by isoprenaline injection. Heart tissues were subsequently harvested for total RNA extraction and library construction. Transcriptome data wereobtained transcriptome data for TTS and FRGs from our laboratory, and sources such as the Ferroptosis Database (FerrDb) and the Gene Expression Omnibus Database (GEO). 57 differentially expressed FRGs (DE-FRGs) were discovered. The LASSO and SVM-RFE algorithms were employed to identify Enpp2, Pla2g6, Etv4, and Il1b as marker genes, and logistic regression was applied to construct a diagnostic model. The important genes were validated by real time PCR and the external dataset. Finally, the extent of immune infiltration was explored. Results: Among the 57 genes, there were 36 up-regulated and 21 down-regulated genes that exhibited distinct expression patterns in the TTS and healthy control samples. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that the enriched pathways were primarily associated with pathways of neurodegeneration-multiple disease, while Gene Ontology (GO) analysis revealed that these genes were primarily linked to cellular response to external stimuli, outer membrane functions, and ubiquitin protein ligase binding. After the identification of four marker genes as potentially effective biomarkers for TTS diagnosis, subsequent logistic regression modeling revealed a receiver operating characteristic curve (ROC) with an AUC of 1.0. The examination of immune cell infiltration showed significantly higher prevalence of activated CD4+ T cells, mast cells, etc., in TTS. Conclusion: Our findings support the theoretical importance of ferroptosis in TTS, highlighting Enpp2, Pla2g6, Etv4, and Il1b as potential diagnostic and therapeutic biomarkers for TTS.

3.
BMC Med Educ ; 22(1): 201, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35321704

RESUMO

OBJECTIVES: The aim of the study was to investigate the work competence of general practitioners (GPs) in the community health services (CHSs) of Shanghai, China. METHODS: A questionnaire was designed based on a previous capacity evaluation indicator system. We used a stratified and proportional cluster sampling method in this self-assessment and cross-sectional study. We collected data with the questionnaire on GPs' demographic variables and work competence including patient care ability, teaching ability, communication skill and coordination ability. Univariate analyses were performed by Mann-Whitney U test and Kolmogorov-Smirnov test. Multivariate analyses were done with generalized liner model with significant univariate factors. RESULTS: A total of 2954 GPs were sampled from 116 CHSs in Shanghai. The response rate was 99.9%. The median scores of patient care ability, teaching ability, communication skill and coordination ability were 80[70-88.75], 76[60-80] and 80[70-85] on a scale of 100, respectively. GPs who were 30-39 years old, or worked in urban CHSs, or took GP trainer's training or had teaching experience got higher scores in patient care ability. GPs who worked for 5-19 years in CHSs, or worked in CHSs with GP training program or took GP trainer's training had higher scores in teaching ability. For communication skill and coordination ability, GPs who worked in CHSs with GP standardized training program, or took GP trainer's training or had teaching experience in CHSs got higher scores. CONCLUSIONS: The work competence of GPs in CHSs of Shanghai could mainly cover daily work, but still needed more improvement in teaching ability.


Assuntos
Clínicos Gerais , Adulto , China , Serviços de Saúde Comunitária , Estudos Transversais , Clínicos Gerais/educação , Humanos , Autoavaliação (Psicologia)
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1494-9, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-30001045

RESUMO

In engineering construction, cement quality directly affects the safety of construction projects. So it is necessary that we use qualified cement in the engineering structure. It is of great signification that a method detects cement raw material rapidly to adjust the mixture ratio of raw ores to ensure the cement quality. Traditional detection method needs sampling, sample preparation and test, etc. With many procedures, the test results are seriously lagged behind the production process. This paper introduces a set of online analysis equipment to determinate elemental composition of cement powder timely based on laser induced breakdown spectroscopy. This equipment is composed of a LIBS detection system and a pneumatic system. The equipment can achieve the real-time measurement for it needn't sample preparation. Thus, it can guide cement raw material proportioning in time. In this paper, we have quantitatively analyzed the main components of Al2O3, CaO, Fe2O3, MgO and SiO2 in the cement raw materials using the full spectrum normalization method as well as the support vector machine. The corresponding maximum absolute errors were 0.34%, 0.35%, 0.07%, 0.14%, and 0.55%, respectively. Results showed that the measurement results of the newly developed LIBS equipment are in accord with those of the conventional chemical method. Furthermore, the measurement precision is in line with X-Ray fluorescence spectrometry. It is confirmed that the LIBS technique could be a prospect method for determination of elemental composition in the cement production industries.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2249-54, 2016 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-30036000

RESUMO

A laboratory cement quality analysis apparatus based on laser-induced breakdown spectroscopy (LIBS) has been developed for rapid analysis of cement composition and ratio values. In this paper, the overall structure, the optical system, the sample preparation process, as well as the spectral data analysis methods are introduced. The calibration model is established with internal standard method. A comparison as to the measurement results between LIBS and X-ray fluorescence spectrometry (XRF) has been made and being analyzed. It shows that by using the LIBS apparatus, the mean absolute error of CaO, SiO2, Al2O3, and Fe2O3 in cement raw materials is 0.46%, 0.25%, 0.13%, and 0.05%, respectively, while the mean absolute error of the ratio value such as KH, SM, and IM in cement clinker is 0.02, 0.05, and 0.04, respectively. The generated cement plasmas are verified to be in the local thermal equilibrium (LTE) condition by calculating both the plasma temperature and the electron density.

6.
J Stroke Cerebrovasc Dis ; 24(9): 1961-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26166420

RESUMO

BACKGROUND: This study aimed to assess the association between diabetes and risk of stroke recurrence (especially ischemic stroke recurrence) and to evaluate whether diabetes was an independent predictor for stroke recurrence in stroke patients with diabetes. METHODS: The relevant studies were identified through searching databases of PubMed, EMBASE, and Cochrane library. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled to evaluate the association between diabetes and risk of stroke recurrence. Funnel plot and Egger's regression tests were used to assess publication bias. All statistical analyses were conducted in Stata 12.0. RESULTS: Eighteen studies containing totally 43,899 participants were included in the meta-analysis. The results showed that stroke recurrence risk of all stroke patients with diabetes was significantly higher than those without diabetes (HR, 1.45; 95% CI, 1.32-1.59), similar results were achieved in ischemic stroke patients (HR, 1.44; 95% CI, 1.28-1.61), and there were no regional differences (Europe: HR, 1.28; 95% CI, 1.13-1.44; USA: HR, 1.89; 95% CI, 1.53-2.33; Asia: HR, 1.57, 95% CI, 1.28-1.92, respectively) and age differences (mean age <70 years: HR, 1.58; 95% CI, 1.34-1.86; mean age ≥70 years: HR, 1.27; 95% CI, 1.11-1.45, respectively). The heterogeneity of all included studies was not statistically significant, and no publication bias was observed. CONCLUSIONS: This meta-analysis shows that diabetes is an independent risk factor for stroke recurrence in stroke patients.


Assuntos
Isquemia Encefálica/etiologia , Diabetes Mellitus/fisiopatologia , Acidente Vascular Cerebral/etiologia , Isquemia Encefálica/complicações , Bases de Dados Bibliográficas/estatística & dados numéricos , Humanos , Recidiva , Fatores de Risco
7.
Cardiology ; 127(2): 96-104, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24280973

RESUMO

OBJECTIVE: To investigate correlations between hypertensive patients' knowledge of hypertension, awareness of hypertension education, self-management behaviors, and hypertension control. METHODS: Hypertensive patients from 5 community health centers in Xuhui District, Shanghai, China, were enrolled into this study. Data were collected via patient interviews and a questionnaire survey. Independent influence factors for hypertension control were identified by logistic regression analysis. RESULTS: In total, 3,328 hypertensive patients, including 1,935 females and 1,390 males with a mean age 70.6 years, were studied. The mean systolic blood pressure was 133.1 mm Hg. The mean diastolic blood pressure was 80.5 mm Hg. Hypertension was controlled in 1,050 (36.1%) patients. Independent influence factors for failed hypertension control were comorbidities, including diabetes mellitus, coronary artery disease, and stroke. Patients who knew that 'high blood pressure is related to salt intake' and were willing to receive regular health education were less likely to fail in hypertension control. Patients who visited clinics because of fear of complications and visited medical institutions other than community health centers for hypertension were more likely to fail in hypertension control. CONCLUSIONS: In Shanghai, failed hypertension control is significantly associated with chronic disease history. Limiting salt intake, receiving regular health education, and visiting community health centers for hypertension care may help control hypertension.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Hipertensão/prevenção & controle , Autocuidado/psicologia , Idoso , Conscientização , China , Feminino , Humanos , Hipertensão/psicologia , Masculino , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Comportamento de Redução do Risco , Inquéritos e Questionários , Resultado do Tratamento
8.
Zhonghua Bing Li Xue Za Zhi ; 42(8): 525-9, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24246917

RESUMO

OBJECTIVE: To investigate the relationship between colorectal adenocarcinoma with invasive micropapillary carcinoma (IMPC) component, lymphovascular invasion, and lymph node metastasis. METHODS: One hundred and thirty one cases of colorectal adenocarcinoma with invasive micropapillary carcinoma component were evaluated by H&E and immunohistochemical staining. The main pathological features, percentage of IMPC component, lymphovascular invasion, and lymph node metastasis were assessed and compared to 296 cases of conventional colorectal adenocarcinoma. RESULTS: The maximum diameter of the tumors of the IMPC group was significantly lower than the conventional group. The degree of differentiation, the lymph node metastatic rate, the average number of metastatic lymph nodes, the number of cases with lymphovascular tumor emboli were significantly higher in the IMPC group (P = 0.000). The rate of distant metastasis at operation was higher in the IMPC group (14.5%) compared to the conventional group (10.8%) even though statistical significance was not achieved (P = 0.278) . In IMPC group, as the IMPC component increased, the rate of lymph node metastasis also showed an increasing trend. The rate of lymph node metastasis were 53.0% (157/296) , 67.7% (42/62) and 85.5% (59/69) " respectively" for conventional adenocarcinoma, adenocarcinoma with ≤ 10% IMPC component and adenocarcinoma with > 10% IMPC component; the difference was statistically significant (P = 0.000). CONCLUSIONS: Compared to conventional colorectal adenocarcinomas, the colorectal carcinomas with IMPC component show a significantly higher rate of lymphovascular invasion, lymph node metastasis and distant metastasis. The percentage of IMPC component in colorectal adenocarcinoma is significantly correlated to the rate of lymph node metastasis. Therefore, presence of IMPC component and degree of tumor differentiation are predicting factors of lymph node metastasis.


Assuntos
Adenocarcinoma/patologia , Carcinoma Papilar/patologia , Neoplasias Colorretais/patologia , Adenocarcinoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD , Caderinas/metabolismo , Carcinoma Papilar/metabolismo , Neoplasias Colorretais/metabolismo , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mucina-1/metabolismo , Metástase Neoplásica , Carga Tumoral , Adulto Jovem
9.
BMC Fam Pract ; 14: 16, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23351010

RESUMO

BACKGROUND: Hypertension prevalence is high in China, while patients' levels of hypertension awareness, treatment and control are low. General practitioners' knowledge and training relating to hypertension prevention may be an important related factor. We aimed to investigate general practitioners' knowledge of hypertension prevention and potential training needs. METHODS: A questionnaire survey was conducted among all general practitioners at five community health service centers selected by convenience sampling. A total of 160 questionnaires were distributed and 147 were returned (response rate 91.9%) The questionnaire included general information; 12 subjective questions on health promotion, education and training needs; and 19 objective questions in 5 domains (epidemiology, diagnosis, treatment, referral and community management) measuring knowledge of hypertension prevention and treatment. RESULTS: The major difficulties in health education practice for general practitioners were poor patient compliance (77.6%) and lack of medical consultation time (49.0%). The average accuracy rate of hypertension prevention knowledge was 49.2%, ranging from 10.5% to 94.7%. The factors associated with accuracy rate were physician's education level (medical university vs. professional school, ß = 13.3, P = 0.003), and type of center (training base vs. community healthcare center, ß = 12.3, P < 0.0001). Most physicians (87.8%) reported being willing to attend training courses regularly and the preferred frequency was once every 2 ~ 3 months (53.5%). The preferred course was medical treatment of hypertension (82.3%) and the most favored training approach was expert lectures (80.3%). CONCLUSIONS: The knowledge level of hypertension prevention is low among general practitioners in urban settings. Physicians working in community clinics where they participate in a series of teaching, assessing and evaluating systems for hypertension prevention perform better than those in general healthcare centers who lack specific training. Continuing hypertension education is urgently needed to ensure that physicians in general practice are aware of and adhere to the national hypertension prevention guidelines.


Assuntos
Medicina Geral/educação , Clínicos Gerais , Conhecimentos, Atitudes e Prática em Saúde , Hipertensão/prevenção & controle , Padrões de Prática Médica , Adulto , China/epidemiologia , Educação Médica Continuada , Escolaridade , Feminino , Fidelidade a Diretrizes , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Educação de Pacientes como Assunto , Guias de Prática Clínica como Assunto , Inquéritos e Questionários , Adulto Jovem
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