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1.
Cardiology ; 148(2): 161-172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36958302

RESUMO

INTRODUCTION: Pulmonary hypertension due to left heart failure (PH-LHF) is a disease with high prevalence and 3-year mortality rates. Consequently, timely identification of patients with high mortality risk is critical. This study aimed to build a nomogram for predicting 3-year mortality and screening high-risk PH-LHF patients. METHODS: This nomogram was developed on a training cohort of 175 patients with PH-LHF diagnosed by right heart catheterization. Multivariate Cox regression was used to identify independent predictors and develop this nomogram. The median total points obtained from the nomogram were used as a cutoff point, and patients were classified into low- and high-risk groups. The concordance index (C-index) and calibration curve were utilized to ascertain the predictive accuracy and discriminative ability of the nomogram. External validation was performed using a validation cohort of 77 PH-LHF patients from other centers. RESULTS: Multivariate Cox regression showed that the New York Heart Association Functional classification (NYHA FC), uric acid level, and mean pulmonary arterial pressure were all independent predictors and incorporated into the nomogram. The nomogram showed good discrimination (C-index of 0.756; 95% CI: 0.688-0.854) and good calibration. The Kaplan-Meier survival analysis showed that patients in the high-risk group had worse survival (p < 0.001). In the external validation, the nomogram showed both good discrimination (C-index of 0.738; 95% CI: 0.591-0.846) and calibration. CONCLUSION: The nomogram had a good performance in predicting 3-year mortality and can effectively identify high-risk patients. The nomogram may help to reduce the mortality of PH-LHF.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Humanos , Nomogramas , Estudos Retrospectivos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Sistema de Registros
2.
Ergonomics ; 66(12): 2212-2222, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36940236

RESUMO

We investigated the prevalence of work-related musculoskeletal symptoms (WMSs) among medical staff and evaluated the associations of different levels of adverse ergonomic factors with WMSs. A total of 6099 Chinese medical staff were asked to complete a self-reported questionnaire to assess the prevalence and risk factors of WMSs from June 2018 to December 2020. A prevalence rate of 57.5% was observed for WMSs among overall medical staffs, which mainly affected the neck (41.7%) and shoulder (33.5%). 'Keeping sitting for long hours very frequently' (OR = 1.26, 95% CI: 1.04, 1.53) was positively associated with WMSs in doctors, while 'keeping sitting for long hours occasionally' (OR = 0.91, 95% CI: 0.85, 0.97) was identified as a protective factor of WMSs in nurses. The associations of adverse ergonomic factors, organisational factors, and environmental factors with WMSs were different among medical staff in different positions.Practitioner summary: We conducted a multi-city study concerning the risk factors of WMSs by carrying out a face-to-face one-to-multiple questionnaire survey among medical staff in China. As a risk factor of WMSs in medical staff, adverse ergonomic factors should be paid more attention by the standard setting department and policy makers.Abbreviations: WMSDs: work-related musculoskeletal disorders; WMSs: work-related musculoskeletal symptoms; MSDs: musculoskeletal disorders; NMQ: Nordic Musculoskeletal Questionnaires; DMQ: Dutch Musculoskeletal Questionnaires; NIOSH: National Institute for Occupational Safety and Health; ORs: odds ratios.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Humanos , Estudos Transversais , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Ergonomia , Inquéritos e Questionários , Fatores de Risco , Corpo Clínico , China/epidemiologia , Prevalência
3.
J Am Chem Soc ; 144(33): 15286-15294, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35796412

RESUMO

Single-molecule white-light emission (SMWLE) has many advantages in practical applications; however, the fabrication of SMWLE from nonconjugated luminescent polymers, namely, clusteroluminogens (CLgens), is still a big challenge. Herein, the first example of linear nonconjugated polyesters with SMWLE is reported. Twenty-four kinds of nonconjugated aliphatic polyesters with tunable clusteroluminescence (CL) colors and efficiency were synthesized by the copolymerization of six epoxides and four anhydrides. Experimental and calculation results prove that, at the primary structure level, the balance of structural flexibility and rigidity via adjusting the side-chain length significantly enhances the efficiency of CL without wavelength change. However, altering the chemical structures of the monomer from succinic anhydride to trans-maleic anhydride (MA), cis-MA, and citraconic anhydride (CA), secondary structures of these polyesters change from helix to straight and folding sheet accompanied by gradually red-shifted CL from 460 to 570 nm due to the increase in through-space n-π* interactions, as demonstrated by the computational and experimental results. Then, pure SMWLE with CIE coordination (0.30, 0.32) based on overlapped short-wavelength and long-wavelength CL is achieved in CA-based polyesters. This work not only provides further insights into the emission mechanism of CL but also provides a new strategy to manipulate the properties of CL by regulating the hierarchical structures of CLgens.


Assuntos
Anidridos Maleicos , Poliésteres , Anidridos/química , Anidridos Maleicos/química , Poliésteres/química , Polimerização , Polímeros/química
4.
Biomacromolecules ; 23(12): 5239-5252, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36354756

RESUMO

Multistimuli-responsive conductive hydrogels have been appealing candidates for multifunctional ionic skin. However, the fabrication of the multistimuli-responsive conductive hydrogels with satisfactory mechanical property to meet the practical applications is still a great challenge. In this study, a novel poly(N-isopropylacrylamide-co-sodium acrylate)/alginate/hectorite clay Laponite XLS (PNIPAM-SA/ALG/XLS) double cross-linked hydrogel with excellent mechanical property, self-recovery ability, temperature/pH-responsive ability, and strain/temperature-sensitive conductivity was fabricated. The PNSAX hydrogel possessed a moderate tensile strength of 290 kPa at a large elongation rate of 1120% and an excellent compression strength of 2.72 MPa at 90%. The hydrogel also possessed excellent mechanical repeatability and self-recovery ability. Thus, the hydrogel could withstand repetitive deformations for long time periods. Additionally, the hydrogel could change its transparency and volume once at a temperature of 44 °C and change its volume at different pHs. Thus, the visual temperature/pH-responsive ability allowed the hydrogel to qualitatively harvest environmental information. Moreover, the hydrogel possessed an excellent conductivity of 0.43 S/m, and the hydrogel could transform large/subtle deformation and temperature information into electrical signal change. Thus, the ultrafast strain/temperature-sensitive conductivity allowed the hydrogel to quantitatively detect large/small-scale human motions as well as environmental temperature. A cytotoxicity test confirmed the good cytocompatibility. Taken together, the hydrogel was suitable for human motion detecting and environmental information harvesting for long time periods. Therefore, the hydrogel has a great application potential as a multifunctional ionic skin and smart sensor.


Assuntos
Hidrogéis , Pele , Humanos , Condutividade Elétrica , Íons , Temperatura
5.
BMC Cardiovasc Disord ; 22(1): 56, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35172722

RESUMO

BACKGROUND: There is no generally accepted comprehensive risk prediction model cooperating risk factors associated with heart failure and pulmonary hemodynamics for patients with pulmonary hypertension due to left heart disease (PH-LHD). We aimed to explore outcome correlates and evaluate incremental prognostic value of pulmonary hemodynamics for risk prediction in PH-LHD. METHODS: Consecutive patients with chronic heart failure undergoing right heart catheterization were prospectively enrolled. The primary endpoint was all-cause mortality. Individual variable selection was performed by machine learning methods. Cox proportional hazards models were conducted to identify the association between variables and mortality. Incremental value of hemodynamics was evaluated based on the Seattle heart failure model (SHFM) and Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) scores. RESULTS: A total of 276 PH-LHD patients were enrolled, with a median follow-up time of 34.7 months. By L1-penalized regression model and random forest approach, diastolic pressure gradient (DPG) and mixed venous oxygen saturation (SvO2) were the hemodynamic predictors most strongly associated with mortality (coefficient: 0.0255 and -0.0176, respectively), with consistent significance after adjusted for SHFM [DPG: HR 1.067, 95% CI 1.024-1.113, P = 0.022; SvO2: HR 0.969, 95% CI 0.953-0.985, P = 0.002] or MAGGIC (DPG: HR 1.069, 95% CI 1.026-1.114, P = 0.011; SvO2: HR 0.970, 95% CI 0.954-0.986, P = 0.004) scores. The inclusion of DPG and SvO2 improved risk prediction compared with using SHFM [net classification improvement (NRI): 0.468 (0.161-0.752); integrated discriminatory index (IDI): 0.092 (0.035-0.171); likelihood ratio test: P < 0.001] or MAGGIC [NRI: 0.298 (0.106-0.615); IDI: 0.084 (0.033-0.151); likelihood ratio: P < 0.001] scores alone. CONCLUSION: In PH-LHD, pulmonary hemodynamics can provide incremental prognostic value for risk prediction. CLINICAL TRIAL REGISTRATION: NCT02164526 at https://clinicaltrials.gov .


Assuntos
Insuficiência Cardíaca/complicações , Hemodinâmica , Hipertensão Pulmonar/etiologia , Circulação Pulmonar , Idoso , Cateterismo Cardíaco , China , Doença Crônica , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/mortalidade , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo
6.
Int J Mol Sci ; 23(13)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35806347

RESUMO

In this work, we report the fabrication and functional demonstration of a kind of dually responsive nanoparticles (NPs) as a potential drug delivery vector. The pH value, corresponding to the acidic microenvironment at the tumor site, and mannitol, to the extracellular trigger agent, were employed as the dually responsive factors. The function of dual responses was achieved by breaking the dynamic covalent bonds between phenylboronic acid (PBA) groups and diols at low pH value (pH 5.0) and/or under the administration of mannitol, which triggered the decomposition of the complex NPs and the concomitant release of anticancer drug of doxorubicin (DOX) loaded inside the NPs. The NPs were composed of modified chitosan (PQCS) with quaternary ammonium and PBA groups on the side chains, heparin (Hep), and poly(vinyl alcohol) (PVA), in which quaternary ammonium groups offer the positive charge for the cell-internalization of NPs, PBA groups serve for the formation of dynamic bonds in responding to pH change and mannitol addition, PVA furnishes the NPs with diol groups for the interaction with PBA groups and the formation of dynamic NPS, and Hep plays the roles of reducing the cytotoxicity of highly positively-charged chitosan and forming of complex NPs for DOX up-loading. A three-step fabrication process of drug-loaded NPs was described, and the characterization results were comprehensively demonstrated. The sustained drug release from the drug-loaded NPs displayed obvious pH and mannitol dependence. More specifically, the cumulative DOX release was increased more than 1.5-fold at pH 5.0 with 20 mg mL-1 mannitol. Furthermore, the nanoparticles were manifested with effective antitumor efficient and apparently enhanced cytotoxicity in response to the acidic pH value and/or mannitol.


Assuntos
Compostos de Amônio , Quitosana , Nanopartículas , Quitosana/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Manitol , Nanopartículas/química
7.
Med Sci Monit ; 25: 9517-9523, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31834876

RESUMO

BACKGROUND A retrospective study of data from a prospective clinical registry was conducted to evaluate the prognostic role of serum calprotectin in patients with diabetes who underwent percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). MATERIAL AND METHODS Data were retrieved for 273 patients with diabetes mellitus who underwent PCI for primary ACS in a single center. Serum calprotectin levels were measured before PCI. Baseline clinical data included the Global Registry of Acute Coronary Events (GRACE) risk score for ACS. All patients underwent regular follow-up for major adverse cardiovascular events (MACE) during 12 months after PCI, including target vessel revascularization (TVR), defined as the need for an unplanned repeat PCI or coronary artery procedure. The predictive value of serum calprotectin for MACE was analyzed by using univariate and multivariate analysis and receiver operating characteristic (ROC) curve analysis. RESULTS At the final follow-up, 47 of the 273 patients studies experienced MACE. Optimal cutoff values for serum calprotectin levels predictive for MACE stratified patients into a high calprotectin group and a low calprotectin group. The incidence of MACE and TVR in the high calprotectin group was significantly greater than in the low calprotectin group (21.9% vs. 11.5%; P=0.02). Multivariate analysis, adjusted for confounders, showed that the serum level of calprotectin was an independent risk factor for MACE (HR, 1.56; 95% CI, 1.08-4.62; P=0.01). CONCLUSIONS In patients with diabetes and the co-morbidity of ACS, a high serum level of calprotectin was associated with a significantly increased risk for MACE following PCI.


Assuntos
Síndrome Coronariana Aguda/terapia , Diabetes Mellitus/sangue , Complexo Antígeno L1 Leucocitário/sangue , Intervenção Coronária Percutânea/métodos , Síndrome Coronariana Aguda/sangue , Idoso , Complicações do Diabetes/sangue , Diabetes Mellitus/metabolismo , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/sangue , Infarto do Miocárdio/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Prognóstico , Curva ROC , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
8.
Chemistry ; 23(12): 2802-2810, 2017 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-27778405

RESUMO

In this study, a uniform complex dual micelle bearing a gadolinium-substituted polyoxometalate core, a hydrophobic middle, and a biocompatible organic shell, which exhibits a uniform size and definite molecular weight and chemical composition, is constructed through a simple two-step process for use as a fluorescence and magnetic resonance imaging (MRI) contrast agent. A paramagnetic polyoxometalate cluster, K13 [Gd(ß2 -SiW11 O39 )2 ], is first encapsulated with a cationic 3-generation dendron (D-3) bearing triethylene glycol monomethyl ether terminal groups through ionic substitution. The formed electrostatic complex, (D-3)13 [Gd(ß2 -SiW11 O39 )2 ] (D-GdSiW), which displays an ambivalent micellar structure, is then demonstrated to act as a suitable carrier for the uptake of cationic fluorescent dyes, forming a loaded complex. The dye-loaded complex D-GdSiW-D is thus proven to display high relaxivity as a contrast agent, maintaining its structural stability under physiological conditions with low cell cytotoxicity. Confocal laser scanning microscopic observation also demonstrates the fluorescence imaging property of the prepared complex upon consumption by MCF-7 cells. Both in vivo fluorescence imaging and MRI further confirm that the complex micelle with dual micellar structure may be a suitable liver-specific contrast agent for clinical diagnosis.

9.
Faraday Discuss ; 196: 245-253, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27900385

RESUMO

A tetraphenylbenzene (TPB) cored luminophore of TPB-AC with aggregation-enhanced emission characteristics was designed and synthesized. TPB-AC could be potentially applied for the fabrication of high performance organic light-emitting diodes (OLEDs) with blue light emission.

10.
RNA Biol ; 13(1): 98-108, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26618242

RESUMO

Antisense Noncoding RNA in the INK4 Locus (ANRIL) is the prime candidate gene at Chr9p21, the well-defined genetic risk locus associated with multiple human diseases including coronary artery disease (CAD), while little is known regarding its role in the pathological processes. Endothelial dysfunction triggers atherosclerotic processes that are causatively linked to CAD. To evaluate the function of ANRIL in human endothelial cells (ECs), we examined ANRIL expression under pathological stimuli and found ANRIL was markedly induced by pro-inflammatory factors. Loss-of-function and chromatin immunoprecipitation approaches revealed that NF-κB mediates TNF-α induced ANRIL expression. RNA sequencing revealed that ANRIL silencing dysregulated expression of inflammatory genes including IL6 and IL8 under TNF-α treatment. We explored the regulatory mechanism of ANRIL on IL6/8 and found that Yin Yang 1 (YY1), an ANRIL binding transcriptional factor revealed by RNA immunoprecipitation, was required for IL6/8 expression under TNF-α treatment. YY1 was enriched at promoter loci of IL6/8 and ANRIL silencing impaired the enrichment, indicating a cooperation between ANRIL and YY1 in the regulation of inflammatory genes. For the first time, we establish the connection between ANRIL and NF-κB pathway and show that ANRIL regulates inflammatory responses through binding with YY1. The newly identified TNF-α-NF-κB-ANRIL/YY1-IL6/8 pathway enhances understanding of the etiology of CAD and provides potential therapeutic target for treatment of CAD.


Assuntos
Células Endoteliais/imunologia , NF-kappa B/genética , RNA Longo não Codificante/genética , Fator de Necrose Tumoral alfa/farmacologia , Fator de Transcrição YY1/genética , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Interleucina-6/genética , Interleucina-8/genética , Regiões Promotoras Genéticas , Transdução de Sinais/efeitos dos fármacos
11.
Artigo em Zh | MEDLINE | ID: mdl-24428987

RESUMO

OBJECTIVE: To investigate the role of calcium activated-potassium channels (KCa) in the injury to rat alveolar macrophages induced by quartz. METHODS: The experiments were conducted on a rat alveolar macrophage cell line (NR8383) in vitro, where crystal silica (100 üg/ml) and amorphous silica (100 üg/ml) were used as the test substances and the cells without any treatment as negative controls. At first the effects of two kinds of quartz were compared. Then KCa special inhibitors (Paxilline for BK, Tram-34 for IK, Apamin for SK) were added in different doses to the in vitro test system with 100 üg/ml crystal quartz as matrix, to observe the function of such channels. Cell viability, lactate dehydrogenase (LDH), interleukin-1ß (IL-1ß) and tumor necrosis factor-a (TNF-α) were tested. RESULTS: Comparing to the negative control group, cell viability reduced, LDH leakage, IL-1ß and TNF-α release increased significantly in the amorphous quartz group, furthermore, the effects by crystal quartz were much more serious than those by amorphous quartz, with a statistical significance (P < 0.01). Comparing to the crystal quartz group, IK blockers (Tram-34) led to increase in cell viability significantly, with a statistical significance (P < 0.01); all the KCa specific blockers (Paxilline, Tram-34, Apamin) could reduce LDH leakage and IL-1ß release, with a statistical significance (P < 0.05); meanwhile, BK and IK blockers (Paxilline,Tram-34) were able to reduce TNF-α release,with a statistical significance (P < 0.05).Reduction of IL-1ß and TNF-α by Tram-34 was dose-dependent, but not so in the other two blockers. CONCLUSION: Blocking calcium-activated potassium channels (KCa) could reduce cell membrane damage as well as IL-1ß and TNF-α release induced by crystal quartz in the rat alveolar macrophages cell line in vitro, which might serve as a signal in the early regulation of inflammatory responses by quartz.


Assuntos
Macrófagos Alveolares/metabolismo , Canais de Potássio Cálcio-Ativados/metabolismo , Quartzo/toxicidade , Animais , Cálcio/metabolismo , Linhagem Celular , Interleucina-1beta/metabolismo , Macrófagos Alveolares/citologia , Ratos , Fator de Necrose Tumoral alfa/metabolismo
12.
Chem Commun (Camb) ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400031

RESUMO

A fluorescence method has been successfully constructed to accurately measure the D/L-Arb configuration content in optical isomers, and its application in ion detection has been expanded, which has greater sensitivity and universality than the circular dichroism (CD) method. It also promotes the study of the emission mechanism of nonconventional luminogens.

13.
Work ; 75(4): 1467-1476, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36565089

RESUMO

BACKGROUND: Parachutists are generally recognized as a "high-risk" group among military personnel. However, the findings came mostly from data analysis without soldiers as subjects. OBJECTIVE: This study aimed to investigate the injury prevalence in Chinese paratroopers on-site and determine the relationship between injury and risk factors encountered during parachuting and land-based training. METHODS: This study consisted of a field study with questionnaire and an experiment on muscle load during the simulated training exercise of platform jumping with surface electromyography (EMG), in which 7230 paratroopers and 38 soldiers were involved respectively. Chi-square test was used for the injury rate analysis, ANOVA and t-test for comparison of EMG data, and logistic regression for the analysis of multiple factors. Taking both intensity and time into consideration, jump-years (J-yrs) was used as a complex indicator for exposure to parachuting. Either injury per 1000 jumps or injured persons per 100 soldiers were calculated as injury prevalence. RESULTS: The overall injury rate among Chinese parachutists was found to be 13.9 injuries per 1000 parachute jumps and 24.5% based on personnel. The person-based injury rate increased with the exposure level significantly (χ2 = 142.06, 2-sided, P < 0.05; trend test also significantly). Among the identified risk factors the uneven terrain was ranked as the most important one by logistic analysis. The EMG amplitude in MVE% increased with the platform height of all the 8 measured muscles and even reached 100% in 4 muscles, showing a high impact at landing. In addition, some characteristics of parachuting injury were also revealed by the injury type and site analysis. CONCLUSION: A dose-response relationship between parachuting and injury was observed significantly in the survey of Chinese paratroopers. Their injury rate was found to be relatively higher than the reported internationally. Landing impact as a critical point for injury seemed to be proved by the investigation and also the experiment with EMG measurement. It is suggested for future studies, to use the person-based injury rate, landing studied in work physiology and with consideration of different landing skills.


Assuntos
Aviação , Militares , Humanos , População do Leste Asiático , Fatores de Risco
14.
Macromol Rapid Commun ; 33(18): 1584-9, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22764123

RESUMO

Tetraphenylethylene (TPE)-substituted poly(allylamine hydrochloride) (PAH-g-TPE) is synthesized by a Schiff base reaction between PAH and TPE-CHO. The PAH-g-TPE forms micelles in water at pH 6, which are further transformed into pure TPE-CHO nanoparticles (NPs) with a diameter of ≈300 nm after incubation in a solution of low pH value. In contrast, only amorphous precipitates are obtained when TPE-CHO methanol solution is incubated in water. The aggregation-induced emission feature of the TPE molecule is completely retained in the TPE NPs, which can be internalized into cells and show blue fluorescence. Formation mechanism of the TPE NPs is proposed by taking into account the guidance effect of linear and charged PAH molecules, and the propeller-stacking manner between the TPE-CHO molecules.


Assuntos
Etilenos/química , Nanopartículas/química , Polímeros/química , Tamanho da Partícula , Polímeros/síntese química
15.
Macromol Rapid Commun ; 33(16): 1356-61, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22605624

RESUMO

The 1,3-dipolar cycloaddition of azides and active internal alkynes has been well studied, but is rarely utilized as a tool for polymer preparation. In this work, an efficient polymerization route is developed. Polycycloaddition of diazide (4) and bis(benzoylethynyl)-benzenes and -butane (3) at elevated temperature has produced the first examples of soluble 1,4,5-trisubstituted polytriazoles PI with satisfactory molecular weights (M(w) up to 16 400) in excellent yields (up to 98.6%). All the obtained polymers are thermally stable, losing merely 5% of their weights at temperatures higher than 367 °C. They exhibit higher refractive indices than some commercial plastics and can be crosslinked upon UV irradiation to generate a 3D photopattern with high resolution. The metal-free feature of such a methodology offers a facile tool to prepare functional materials free from the contamination of metal species.


Assuntos
Alcinos/química , Azidas/química , Polímeros/síntese química , Estrutura Molecular , Polimerização , Polímeros/química
16.
Ann Occup Hyg ; 56(4): 401-12, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22228144

RESUMO

In China, dust samplers were originally designed to collect 'total dust' for a short term during production, which is different from the widely adopted sampling strategy for dust. With the aim to provide the conversion factor from Chinese total dust to US and German respirable dust and to look at the influences on conversion factors from environment, production, and instruments, a comparative field study on the dust concentration measurements by different sampling methods was carried out in the same Chinese industries as in the 1989-1990 study and in some other factories. A supplemental experiment was also conducted in a wind tunnel. Dust concentration was measured with a parallel sampling strategy by using the following samplers: 10-mm nylon cyclone for US respirable dust (AR), FSP-Berufsgenossenschaftliches Institut für Arbeitssicherheit (BIA) cyclone for German respirable dust (GR), and samplers for Chinese total dust (CT). Totally, 1434 samples were collected (269 AR, 198 GR, and 967 CT), from which 429 matched sample pairs (249 pairs of AR/CT, 180 GR/CT) were available to calculate conversion ratios. Industry- and job-based conversion factors are presented in this study. The conversion factor of AR/CT was 0.38 for tungsten mines, 0.19 for copper/iron mines, 0.65 for tin mines, and 0.20 for pottery industry, while the factor of GR/CT was 0.69 for tungsten, 0.37 for copper/iron, and 0.52 for pottery. In the job category, AR/CT factors varied from 0.16 to 0.96 and GR/CT from 0.12 to 0.72. For the industries studied in 1988-1989, the AR/CT and GR/CT factors were 0.29 and 0.45, respectively. Both factors were definitely influenced by production, CT dust concentration, sample gain, and variation of dust concentration. Moreover, the respirable dust concentration by FSP-BIA was significantly higher than that by 10-mm cyclones, 63.27-73.10% more as showed also by the wind tunnel experiment. Meanwhile, the GR/CT ratio was significantly larger than the AR/CT in every industry or job with only few exceptions. The GR/CT estimates should be considered as independent ones. Following these results, there is a need to use 'ideal samplers' (consistent with the internationally accepted respirable fraction) in practice and to assess the existent samplers in order to homogenize the exposure data situation.


Assuntos
Poluentes Ocupacionais do Ar/análise , Poeira/análise , Monitoramento Ambiental/métodos , Exposição Ocupacional/análise , China , Monitoramento Ambiental/instrumentação , Humanos , Indústrias , Local de Trabalho/normas
17.
J Huazhong Univ Sci Technolog Med Sci ; 32(4): 630-636, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22886983

RESUMO

There are actually no sufficient data for lifting technique assessment. A laboratory study was undertaken to determine the effect of 3 regular lifting techniques on erector muscle activation, cardiovascular strain and subjective response. Thirty student volunteers participated in the study, and were required to lift a weight with different techniques. Stoop-, squat-, semi-squat-lifting resulted in 3, 2 and 1 time of the highest percentage of the maximum voluntary electrical activation (MVE%) respectively. In the same order, the lowest median frequency (MF) existed 1, 1 and 2 times. Muscle fatigue was 4 times in squat, 36 in semi-squat and 43 in stoop lifting. Heart rate was the highest in squat and lowest in stoop respectively, with a middle level in semi-squat lifting. It may be recommended to adopt mainly the semi-squat technique for daily lifting works. For heavy lifting, it should use the squat technique. Stoop lifting may also be used alternatively but for light things.


Assuntos
Fenômenos Biomecânicos/fisiologia , Remoção , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
18.
Front Cardiovasc Med ; 9: 908215, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35983183

RESUMO

Background: Pulmonary hypertension due to left heart failure (PH-LHF) is currently the most common form of pulmonary hypertension (PH) encountered in clinical practice. Despite significant advances that have improved our understanding of PH-LHF over the past two decades, the mortality is still high in recent decades. This study aimed to describe the prevalence and survival of patients with PH-LHF, and explored the potential risk factors which may predict the prognosis of PH-LHF. Methods: A retrospective analysis of a prospective cohort study of left heart failure (LHF) patients who underwent right heart catheterization (RHC) between January 2013 and November 2016 was performed. The endpoint was all-cause mortality. Follow-ups were performed every 6 months ± 2 weeks. Results: A total of 480 patients with LHF were enrolled, with 215 (44.8%) having PH-LHF. The proportion of PH-LHF was significantly lower in coronary artery disease (CAD) group than without CAD (41.3 vs. 57.8%, p = 0.003). However, multivariable logistic regression analysis revealed that CAD was not associated with PH-LHF (Adjusted OR: 1.055, 95% CI: 0.576 - 1.935, p = 0.862). 75 of 215 (34.9%) patients with PH-LHF died during a median follow-up period of 84.6 months. The 1-, 3-, 5-, and 8-year survival rates of all PH-LHF patients were 94.3, 76.9, 65.8, and 60.2%, respectively. New York Heart Association Functional Class (NYHA FC), hemoglobin, and systolic pulmonary artery pressure (sPAP) were associated with mortality of PH-LHF in multivariate Cox analysis. Conclusion: PH is commonly identified in patients with LHF, with a prevalence of approximately 45%. The mortality is still high in patients with PH-LHF. NYHA FC, hemoglobin, and sPAP are independent risk predictors of mortality for PH-LHF. These findings may be useful for risk stratification in future clinical trial enrollment.

19.
Front Cardiovasc Med ; 9: 983803, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035936

RESUMO

Background: Patients with left heart failure (LHF) are often associated with the development of pulmonary hypertension (PH) which leads to an increased risk of death. Recently, the diagnostic standard for PH has changed from mean pulmonary arterial pressure (mPAP) ≥25 mmHg to >20 mmHg. Nonetheless, the effect of borderline PH (mPAP: 21-24 mmHg) on the prognosis of LHF patients is unclear. This study aimed to investigate the relationship between borderline PH and 3-year clinical outcomes in LHF patients. Methods: A retrospective analysis of a prospective cohort study was done for LHF patients who underwent right heart catheterization (RHC) between January 2013 and November 2016. The primary outcome was all-cause mortality; the secondary outcome was rehospitalization. Results: Among 344 patients, 62.5% were identified with a proportion of PH (mPAP ≥ 25), 10.8% with borderline PH (21-24), and 26.7% with non-PH (≤20), respectively. Multivariable Cox analysis revealed that borderline PH patients had a higher adjusted mortality risk (HR = 3.822; 95% CI: 1.043-13.999; p = 0.043) than non-PH patients. When mPAP was treated as a continuous variable, the hazard ratio for death increased progressively with increasing mPAP starting at 20 mmHg (HR = 1.006; 95% CI: 1.001-1.012). There was no statistically significant difference in adjusted rehospitalization between borderline PH and non-PH patients (HR = 1.599; 95% CI: 0.833-3.067; p = 0.158). Conclusions: Borderline PH is independently related to increased 3-year mortality in LHF patients. Future research is needed to evaluate whether more close monitoring, and managing with an intensifier improves clinical outcomes in borderline PH caused by LHF. Clinical trials registration: www.clinicaltrials.gov NCT02164526.

20.
Chin Med J (Engl) ; 135(15): 1837-1845, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-36195993

RESUMO

BACKGROUND: Coronary artery disease (CAD) is the commonest cause of heart failure (HF), whereas pulmonary hypertension (PH) has not been established or reported in this patient population. Therefore, we assessed the prevalence, risk factors, and survival in CAD-associated HF (CAD-HF) complicated with PH. METHODS: Symptomatic CAD-HF patients were continuously enrolled in this prospective, multicenter registry study. Echocardiography, coronary arteriography, left and right heart catheterization (RHC), and other baseline clinical data were recorded. Patients were followed up and their survival was recorded. RESULTS: One hundred and eighty-two CAD-HF patients were enrolled, including 142 with HF with a preserved ejection fraction (heart failure with preserved ejection fraction [HFpEF]; left ventricular ejection fraction [LVEF] ≥50%) and 40 with a reduced ejection fraction (heart failure with reduced ejection fraction [HFrEF]; LVEF < 50%). PH was diagnosed with RHC in 77.5% of patients. Patients with PH showed worse hemodynamic parameters and higher mortality. HFrEF-PH patients had worse survival than HFpEF-PH patients. CAD-HF patients with an enlarged left ventricular end-diastolic diameter and reduced hemoglobin were at higher risk of PH. Nitrate treatment reduced the risk of PH. Elevated creatinine and mean pulmonary arterial pressure (mPAP), diastolic pressure gradient (DPG) ≥7 mmHg, and previous myocardial infarction (MI) entailed a higher risk of mortality in CAD-HF patients with PH. CONCLUSIONS: PH is common in CAD-HF and worsens the hemodynamics and survival in these patients. Left ventricle enlargement and anemia increase the risk of PH in CAD-HF. Patients may benefit from nitrate medications. Renal impairment, elevated mPAP, DPG ≥7 mmHg, and previous MI are strong predictors of mortality in CAD-HF-PH patients. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02164526.


Assuntos
Doença da Artéria Coronariana , Insuficiência Cardíaca , Hipertensão Pulmonar , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/epidemiologia , Creatinina , Insuficiência Cardíaca/complicações , Humanos , Hipertensão Pulmonar/complicações , Nitratos , Prevalência , Prognóstico , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Volume Sistólico , Função Ventricular Esquerda
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