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1.
Occup Environ Med ; 80(5): 260-267, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36972977

RESUMO

BACKGROUND: We previously found that occupational exposure to diesel engine exhaust (DEE) was associated with alterations to 19 biomarkers that potentially reflect the mechanisms of carcinogenesis. Whether DEE is associated with biological alterations at concentrations under existing or recommended occupational exposure limits (OELs) is unclear. METHODS: In a cross-sectional study of 54 factory workers exposed long-term to DEE and 55 unexposed controls, we reanalysed the 19 previously identified biomarkers. Multivariable linear regression was used to compare biomarker levels between DEE-exposed versus unexposed subjects and to assess elemental carbon (EC) exposure-response relationships, adjusted for age and smoking status. We analysed each biomarker at EC concentrations below the US Mine Safety and Health Administration (MSHA) OEL (<106 µg/m3), below the European Union (EU) OEL (<50 µg/m3) and below the American Conference of Governmental Industrial Hygienists (ACGIH) recommendation (<20 µg/m3). RESULTS: Below the MSHA OEL, 17 biomarkers were altered between DEE-exposed workers and unexposed controls. Below the EU OEL, DEE-exposed workers had elevated lymphocytes (p=9E-03, false discovery rate (FDR)=0.04), CD4+ count (p=0.02, FDR=0.05), CD8+ count (p=5E-03, FDR=0.03) and miR-92a-3p (p=0.02, FDR=0.05), and nasal turbinate gene expression (first principal component: p=1E-06, FDR=2E-05), as well as decreased C-reactive protein (p=0.02, FDR=0.05), macrophage inflammatory protein-1ß (p=0.04, FDR=0.09), miR-423-3p (p=0.04, FDR=0.09) and miR-122-5p (p=2E-03, FDR=0.02). Even at EC concentrations under the ACGIH recommendation, we found some evidence of exposure-response relationships for miR-423-3p (ptrend=0.01, FDR=0.19) and gene expression (ptrend=0.02, FDR=0.19). CONCLUSIONS: DEE exposure under existing or recommended OELs may be associated with biomarkers reflective of cancer-related processes, including inflammatory/immune response.


Assuntos
Poluentes Ocupacionais do Ar , MicroRNAs , Exposição Ocupacional , Humanos , Emissões de Veículos/análise , Poluentes Ocupacionais do Ar/efeitos adversos , Poluentes Ocupacionais do Ar/análise , Estudos Transversais , União Europeia , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Biomarcadores/análise
2.
Herz ; 48(1): 64-71, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34981128

RESUMO

BACKGROUND: The aim of this study was to investigate the effects of thin-cap fibroatheromas (TCFAs) on stent neointimal coverage at the 9­month follow-up after EXCEL stent implantation assessed by optical coherence tomography (OCT). METHODS: A total of 93 patients with non-ST elevation acute coronary syndrome (NSTEACS) who underwent EXCEL stent implantation were prospectively enrolled in the study and divided into a TCFA group (n = 47) and a non-TCFA group (n = 46) according to whether EXCEL stents covered the TCFAs. A TCFA was defined as a plaque with lipid content in more than one quadrant and fibrous cap thickness measuring less than 65 µm. The effect of TCFAs on stent neointimal coverage at the 9­month follow-up after stent implantation was evaluated by OCT. The primary study endpoints were the incidence of neointimal uncoverage and stent malapposition. RESULTS: At the 9­month follow-up, the minimal lumen diameter of the TCFA group tended to be smaller (2.8 ± 0.8 vs. 2.1 ± 0.8, p = 0.08) and the diameter of stenosis in the TCFA group tended to be larger (15.1 ± 10.3% vs. 26.3 ± 15.1%, p = 0.08) than those in the non-TCFA group. The mean intimal thickness of the TCFA group was significantly lower than that of the non-TCFA group (67.2 ± 35.5 vs. 145.1 ± 48.7, p < 0.001). The uncovered struts (10.1 ± 9.7 vs. 4.8 ± 4.3, p = 0.05) and malapposed struts (2.1 ± 4.7 vs. 0.3 ± 0.5, p = 0.003) in the TCFA group were more significant than those in the non-TCFA group. Multivariate analysis showed that TCFAs and lesion types were independent predictors of incomplete neointimal coverage (p < 0.05), and lesion types were independent predictors of stent malapposition (p < 0.05). CONCLUSION: In patients with NSTEACS, TCFAs delayed endothelium coverage at 9 months after stent implantation, and TCFAs were independent predictors of incomplete neointimal coverage of the stent.


Assuntos
Síndrome Coronariana Aguda , Aterosclerose , Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento , Stents , Neointima/diagnóstico por imagem , Neointima/patologia , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/cirurgia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia
3.
Int J Mol Sci ; 24(3)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36768624

RESUMO

Flame-retardant cycloaliphatic epoxy systems have long been studied; however, the research suffers from slow and unsatisfactory advances. In this work, we synthesized a kind of phosphorus-containing difunctional cycloaliphatic epoxide (called BCEP). Then, triglycidyl isocyanurate (TGIC) was mixed with BCEP to achieve epoxy systems that are rich in phosphorus and nitrogen elements, which were cured with 4-methylhexahydrobenzene anhydride (MeHHPA) to obtain a series of flame-retardant epoxy resins. Curing behaviors, flame retardancy, thermal behaviors, dielectric performance, and the chemical degradation behaviors of the cured epoxy system were investigated. BCEP-TGIC systems showed a high curing activity, and they can be efficiently cured, in which the incorporation of TGIC decreased the curing activity of the resin. As the ratio of BCEP and TGIC was 1:3, the cured resin (BCEP1-TGIC3) showed a relatively good flame retardancy with a limiting oxygen index value of 25.2%. In the cone calorimeter test, they presented a longer time to ignition and a lower heat release than the commercially available cycloaliphatic epoxy resins (ERL-4221). BCEP-TGIC systems presented good thermal stability, as the addition of TGIC delayed the thermal weight loss of the resin. BCEP1-TGIC3 had high dielectric performance and outperformed ERL-4221 over a frequency range of 1 HZ to 1 MHz. BCEP1-TGIC3 could achieve degradation under mild conditions in an alkali methanol/water solution. Benefiting from the advances, BCEP-TGIC systems have potential applications as electronic packaging materials in electrical and electronic fields.


Assuntos
Resinas Epóxi , Retardadores de Chama , Álcalis , Anidridos , Eletrônica , Fósforo , Resinas Vegetais
4.
Knowl Inf Syst ; 65(6): 2699-2729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035130

RESUMO

Spatial data are ubiquitous, massively collected, and widely used to support critical decision-making in many societal domains, including public health (e.g., COVID-19 pandemic control), agricultural crop monitoring, transportation, etc. While recent advances in machine learning and deep learning offer new promising ways to mine such rich datasets (e.g., satellite imagery, COVID statistics), spatial heterogeneity-an intrinsic characteristic embedded in spatial data-poses a major challenge as data distributions or generative processes often vary across space at different scales, with their spatial extents unknown. Recent studies (e.g., SVANN, spatial ensemble) targeting this difficult problem either require a known space-partitioning as the input, or can only support very limited number of partitions or classes (e.g., two) due to the decrease in training data size and the complexity of analysis. To address these limitations, we propose a model-agnostic framework to automatically transform a deep learning model into a spatial-heterogeneity-aware architecture, where the learning of arbitrary space partitionings is guided by a learning-engaged generalization of multivariate scan statistic and parameters are shared based on spatial relationships. Moreover, we propose a spatial moderator to generalize learned space partitionings to new test regions. Finally, we extend the framework by integrating meta-learning-based training strategies into both spatial transformation and moderation to enhance knowledge sharing and adaptation among different processes. Experiment results on real-world datasets show that the framework can effectively capture flexibly shaped heterogeneous footprints and substantially improve prediction performances.

5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 47(4): 424-427, 2023 Jul 30.
Artigo em Zh | MEDLINE | ID: mdl-37580294

RESUMO

Continuous glucose monitoring (CGM) technology developed rapidly in recent years, and new products came out all the time. Nowadays, CGM plays an important role in diabetes management and has been recommended by various guideline all over the world. CGM equipment classification, progress on glucose sensor technology, and the new application and expansion of CGM technology in the field of diabetes and non-diabetes were briefly introduced in the study.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Glicemia , Automonitorização da Glicemia , Tecnologia
6.
Int J Mol Sci ; 23(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35682666

RESUMO

Metformin is still being investigated due to its potential use as a therapeutic agent for managing overweight or obesity. However, the underlying mechanisms are not fully understood. Inhibiting the adipogenesis of adipocyte precursors may be a new therapeutic opportunity for obesity treatments. It is still not fully elucidated whether adipogenesis is also involved in the weight loss mechanisms by metformin. We therefore used adipose-derived stem cells (ADSCs) from inguinal and epididymal fat pads to investigate the effects and mechanisms of metformin on adipogenesis in vitro. Our results demonstrate the similar effect of metformin inhibition on lipid accumulation, lipid droplets fusion, and growth in adipose-derived stem cells from epididymal fat pads (Epi-ADSCs) and adipose-derived stem cells from inguinal fat pads (Ing-ADSCs) cultures. We identified that cell death-inducing DFFA-like effector c (Cidec), Perilipin1, and ras-related protein 8a (Rab8a) expression increased ADSCs differentiation. In addition, we found that metformin inhibits lipid droplets fusion and growth by decreasing the expression of Cidec, Perilipin1, and Rab8a. Activation of AMPK pathway signaling in part involves metformin inhibition on Cidec, Perilipin1, and Rab8a expression. Collectively, our study reveals that metformin inhibits lipid storage, fusion, and growth of lipid droplets via reduction in Cidec and its regulatory factors in ADSCs cultures. Our study supports the development of clinical trials on metformin-based therapy for patients with overweight and obesity.


Assuntos
Gotículas Lipídicas , Metformina , Adipócitos/metabolismo , Adipogenia , Tecido Adiposo/metabolismo , Animais , Humanos , Gotículas Lipídicas/metabolismo , Lipídeos , Metformina/metabolismo , Metformina/farmacologia , Obesidade/metabolismo , Sobrepeso/metabolismo , Proteínas/metabolismo , Ratos , Células-Tronco/metabolismo
7.
Occup Environ Med ; 78(11): 823-828, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34039759

RESUMO

BACKGROUND: Millions of workers worldwide are exposed to diesel engine exhaust (DEE), a known genotoxic carcinogen. Alu retroelements are repetitive DNA sequences that can multiply and compromise genomic stability. There is some evidence linking altered Alu repeats to cancer and elevated mortality risks. However, whether Alu repeats are influenced by environmental pollutants is unexplored. In an occupational setting with high DEE exposure levels, we investigated associations with Alu repeat copy number. METHODS: A cross-sectional study of 54 male DEE-exposed workers from an engine testing facility and a comparison group of 55 male unexposed controls was conducted in China. Personal air samples were assessed for elemental carbon, a DEE surrogate, using NIOSH Method 5040. Quantitative PCR (qPCR) was used to measure Alu repeat copy number relative to albumin (Alb) single-gene copy number in leucocyte DNA. The unitless Alu/Alb ratio reflects the average quantity of Alu repeats per cell. Linear regression models adjusted for age and smoking status were used to estimate relations between DEE-exposed workers versus unexposed controls, DEE tertiles (6.1-39.0, 39.1-54.5 and 54.6-107.7 µg/m3) and Alu/Alb ratio. RESULTS: DEE-exposed workers had a higher average Alu/Alb ratio than the unexposed controls (p=0.03). Further, we found a positive exposure-response relationship (p=0.02). The Alu/Alb ratio was highest among workers exposed to the top tertile of DEE versus the unexposed controls (1.12±0.08 SD vs 1.06±0.07 SD, p=0.01). CONCLUSION: Our findings suggest that DEE exposure may contribute to genomic instability. Further investigations of environmental pollutants, Alu copy number and carcinogenesis are warranted.


Assuntos
Poluentes Ocupacionais do Ar/análise , Elementos Alu , Exposição Ocupacional/efeitos adversos , Emissões de Veículos/análise , Adulto , Carbono/análise , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Retroelementos , Fumar
8.
Int J Qual Health Care ; 31(7): 568-574, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30388240

RESUMO

QUALITY PROBLEM OR ISSUE: Chinese medical institutions need clinical guidelines to improve healthcare quality. Unfamiliarity with clinical methodology and procedures leads to poor quality. INITIAL ASSESSMENT: This study examined 327 clinical guidelines made in China during the period of 2006-10 and found these clinical guidelines have many problems in terms of guideline making procedures-compliant process, conflicts of interest disclosure. CHOICE OF SOLUTION: Chinese Medical Association organized a working group in 2014 to make a national [Guideline for Clinical Guidelines Constitution/Amendment] and invited multidiscipline experts to prove its possibility. IMPLEMENTATION: Experts investigated and reviewed numerous domestic and foreign published literature within the past 2 years, concluded that a clinical guideline should have following seven components: I. Objective; II. General Principle; III. Procedure and Methodology; IV. Confirmation, Publication and Dissemination; V. Update and Amendment; VI. Implementation and Outcome Validation; VII. Reference. EVALUATION: The [Guideline for Clinical Guidelines Constitution/Amendment] will improve the quality of Chinese clinical guidelines and regulate applications, as well as outcome evaluations of clinical guidelines in China. LESSONS LEARNED: Standardized methodology and procedures are important for constituting high-quality clinical guidelines.


Assuntos
Guias de Prática Clínica como Assunto/normas , China
9.
Lab Invest ; 98(7): 871-882, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29497174

RESUMO

Hepatocellular carcinoma (HCC) is one of the most lethal malignancies due to its high frequency of metastasis via the epithelial-mesenchymal transition (EMT) pathway. Hepatic stimulator substance (HSS) can protect hepatocytes from injury and promote liver growth. Recent studies indicated that HSS expression is increased in HCC tissues; however, whether HSS expression is potentially associated with HCC metastasis, particularly through the EMT pathway, remains largely unknown. In this study, the relationship between HSS expression and HCC metastasis was investigated in clinical samples of HCC. Meanwhile, the regulation of HCC metastasis and EMT progression by HSS were also analyzed in both in vitro and in vivo models. The results showed that the expression of 23 kDa HSS was significantly decreased among HCC tissues with angioinvasion. A decrease in HSS predicted poor prognosis with a lower survival rate. Furthermore, the growth of xenograft tumors after inoculating MHCC97H-HSS-shRNA (HCC) cells into nude mice was notably accelerated compared to those inoculated with HSS-expressing cells. Further analysis revealed that knockdown of HSS expression in both MHCC97H and HepG2 cells could enhance the migration of these HCC cells. Concurrently, interference of HSS expression by shRNA promoted conversion of morphologically epithelial-like HCC cells into mesenchymal-like cells, together with downregulations of epithelial markers (such as E-cadherin and zonula occludens-1) and upregulation of mesenchymal-like makers (such as α-SMA, ß-catenin, and fibronectin). Furthermore, it was demonstrated that, as well as promoting EMT, HSS-shRNA induced the phosphorylation of extracellular signal-regulated kinase (ERK) and elevated the expression of the EMT-related transcription factor Snail. Specific inhibition of HSS-shRNA-induced ERK phosphorylation by PD98059 attenuated HCC cell migration in a dose-dependent manner. In conclusion, we demonstrated that downregulation of HSS expression contributes to HCC metastasis partially through the ERK-activated EMT pathway.


Assuntos
Carcinoma Hepatocelular/metabolismo , Transição Epitelial-Mesenquimal/genética , Neoplasias Hepáticas/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Peptídeos/genética , Peptídeos/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Transição Epitelial-Mesenquimal/fisiologia , Feminino , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Peptídeos/química , Peptídeos/fisiologia
10.
Carcinogenesis ; 38(11): 1104-1111, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-28968774

RESUMO

The relationship between diesel engine exhaust (DEE), a known lung carcinogen, and immune/inflammatory markers that have been prospectively associated with lung cancer risk is not well understood. To provide insight into these associations, we conducted a cross-sectional molecular epidemiology study of 54 males highly occupationally exposed to DEE and 55 unexposed male controls from representative workplaces in China. We measured plasma levels of 64 immune/inflammatory markers in all subjects using Luminex bead-based assays, and compared our findings to those from a nested case-control study of these markers and lung cancer risk, which had been conducted among never-smoking women in Shanghai using the same multiplex panels. Levels of nine markers that were associated with lung cancer risk in the Shanghai study were altered in DEE-exposed workers in the same direction as the lung cancer associations. Among these, associations with the levels of CRP (ß= -0.53; P = 0.01) and CCL15/MIP-1D (ß = 0.20; P = 0.02) were observed in workers exposed to DEE and with increasing elemental carbon exposure levels (Ptrends <0.05) in multivariable linear regression models. Levels of a third marker positively associated with an increased lung cancer risk, CCL2/MCP-1, were higher among DEE-exposed workers compared with controls in never and former smokers, but not in current smokers (Pinteraction = 0.01). The immunological differences in these markers in DEE-exposed workers are consistent with associations observed for lung cancer risk in a prospective study of Chinese women and may provide some insight into the mechanistic processes by which DEE causes lung cancer.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Biomarcadores/metabolismo , Gasolina/efeitos adversos , Inflamação/metabolismo , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/metabolismo , Exposição Ocupacional/efeitos adversos , Adulto , Carcinógenos , Estudos de Casos e Controles , China , Estudos Transversais , Humanos , Inflamação/induzido quimicamente , Pulmão/metabolismo , Masculino , Epidemiologia Molecular/métodos , Estudos Prospectivos , Medição de Risco , Emissões de Veículos
11.
Lab Invest ; 97(12): 1400-1411, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28825695

RESUMO

Hepatocellular carcinoma (HCC) is highly chemoresistant and therefore challenges both physicians and patients. Augmenter of liver regeneration (ALR), previously also known as 'hepatic stimulator substance', is reported to inhibit the epithelial-mesenchymal transition (EMT) in HCC, one of the frequent events that occur in cancer metastasis, suggesting that ALR is involved in HCC. In this study, we report for the first time that the transfection of ALR enhances the antitumor effect of chemotherapy with doxorubicin, a typical anticancer drug, on HCC in vitro and in vivo. The efflux of doxorubicin from ALR-transfected HCC cells is efficiently suppressed. This implies the intracellular retention of doxorubicin in tumor cells, which is at least partly attributable to the effective inhibition of ABCB1 and ABCG2 transporter expression in ALR-expressing cells. The downregulation of ALR expression by short hairpin RNA diminishes the antitumor effect of ALR. We further demonstrate that ALR inhibits the AKT/Snail signaling pathway, resulting in the downregulation of ABCB1 and ABCG2 expression. In conclusion, our results suggest that ALR is a potential chemotherapeutic agent against HCC.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Redutases do Citocromo , Doxorrubicina/farmacologia , Neoplasias Hepáticas/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/análise , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/análise , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Animais , Redutases do Citocromo/genética , Redutases do Citocromo/metabolismo , Redutases do Citocromo/farmacologia , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Oxirredutases atuantes sobre Doadores de Grupo Enxofre , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Occup Environ Med ; 73(2): 83-90, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26491144

RESUMO

OBJECTIVES: Diesel engine exhaust (DEE) is a ubiquitous environmental pollutant and is carcinogenic to humans. To seek early and sensitive biomarkers for prediction of adverse health effects, we analysed the components of DEE particles, and examined the genetic and oxidative damages in DEE-exposed workers. METHODS: 101 male diesel engine testing workers who were constantly exposed to DEE and 106 matched controls were enrolled in the present study. The components of DEE were analysed, including fine particulate matter (PM2.5), element carbon (EC), nitrogen dioxide (NO2), sulfur dioxide (SO2) and polycyclic aromatic hydrocarbons (PAHs). Postshift urine samples were collected and analysed for 1-hydroxypyrene (1-OHP), an internal exposure marker for DEE. Levels of DNA strand breaks and oxidised purines, defined as formamidopyrimidine-DNA glycosylase (FPG) sites in leucocytes, were measured by medium throughput Comet assay. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) was also used to determine the level of oxidative stress. RESULTS: We found higher levels of PM2.5, EC, NO2, SO2 and PAHs in the diesel engine testing workshop and significantly higher urinary 1-OHP concentrations in exposed subjects (p<0.001). Compared with controls, the levels of parameters in normal Comet and FPG-Comet assay were all significantly higher in DEE-exposed workers (p<0.001), and in a dose-dependent and time-dependent manner. There were no significant differences between DEE-exposed workers and controls in regard to leucocyte FPG sensitive sites and urinary 8-OHdG levels. CONCLUSIONS: These findings suggest that DEE exposure mainly induces DNA damage, which might be used as an early biomarker for risk assessment of DEE exposure.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Poluição do Ar/efeitos adversos , Dano ao DNA , Exposição Ocupacional/efeitos adversos , Pirenos/urina , Emissões de Veículos/análise , Trabalho , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Poluentes Ocupacionais do Ar/análise , Poluição do Ar/análise , Biomarcadores/metabolismo , Carbono/efeitos adversos , Carbono/análise , Ensaio Cometa , DNA-Formamidopirimidina Glicosilase/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Humanos , Masculino , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Estresse Oxidativo , Material Particulado/efeitos adversos , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Risco , Dióxido de Enxofre/efeitos adversos , Dióxido de Enxofre/análise , Adulto Jovem
13.
J Opt Soc Am A Opt Image Sci Vis ; 33(11): 2256-2263, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27857446

RESUMO

It has been proved that localized approximation (LA) is the most efficient way to evaluate the beam shape coefficients (BSCs) in generalized Lorenz-Mie theory. The BSCs are usually expressed in the form of multiple summations of an infinite series of terms, which is cumbersome to calculate, and the infinite series is frequently slowly convergent. In this paper, we present a compact expression of the BSCs for an elliptical Gaussian beam based on the LA that is more convenient and efficient for numerical computations. A comparison with the integral LA is made, showing the reliability, stability, and efficiency of the presented formulation.

14.
BMC Med Inform Decis Mak ; 16 Suppl 2: 70, 2016 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-27459962

RESUMO

BACKGROUND: Epileptic seizure is a serious health problem in the world and there is a huge population suffering from it every year. If an algorithm could automatically detect seizures and deliver the patient therapy or notify the hospital, that would be of great assistance. Analyzing the scalp electroencephalogram (EEG) is the most common way to detect the onset of a seizure. In this paper, we proposed the context-learning based EEG analysis for seizure detection (Context-EEG) algorithm. METHODS: The proposed method aims at extracting both the hidden inherent features within EEG fragments and the temporal features from EEG contexts. First, we segment the EEG signals into EEG fragments of fixed length. Second, we learn the hidden inherent features from each fragment with a sparse auto-encoder and thus the dimensionality of the original data is reduced. Third, we translate each EEG fragment to an EEG word so that a continuous EEG signal is converted to a sequence of EEG words. Fourth, by analyzing the context information of EEG words, we learn the temporal features for EEG signals. And finally, we concatenate the hidden features and the temporal features together to train a binary classifier which can be used to detect the onset of an epileptic sezure. RESULTS: 4302 EEG fragments from four different patients are used to train and test our model. An error rate of 22.93 % is achieved by our model as a general, non-patient specific seizure detector. The error rate of our model is averagely 16.7 % lower than the other baseline models. Receiver operating characteristics (ROC curve) and area under curve (AUC) confirm the effectiveness of our model. Furthermore, we discuss the extracted features and how to reconstruct the original data based on the extracted features, as well as the parameter sensitivity. CONCLUSIONS: Given a EEG fragment, by extracting high-quality features (the hidden inherent features and temporal features) from the EEG signals, our Context-EEG model is able to detect the onset of a seizure with high accuracy in real time.


Assuntos
Eletroencefalografia/métodos , Epilepsia/diagnóstico , Aprendizado de Máquina , Modelos Neurológicos , Processamento de Sinais Assistido por Computador , Humanos
15.
Occup Environ Med ; 72(5): 354-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25673341

RESUMO

BACKGROUND: The International Agency for Research on Cancer recently classified diesel engine exhaust (DEE) as a Group I carcinogen based largely on its association with lung cancer. However, the exposure-response relationship is still a subject of debate and the underlying mechanism by which DEE causes lung cancer in humans is not well understood. METHODS: We conducted a cross-sectional molecular epidemiology study in a diesel engine truck testing facility of 54 workers exposed to a wide range of DEE (ie, elemental carbon air levels, median range: 49.7, 6.1-107.7 µg/m(3)) and 55 unexposed comparable controls. RESULTS: The total lymphocyte count (p=0.00044) and three of the four major lymphocyte subsets (ie, CD4+ T cells (p=0.00019), CD8+ T cells (p=0.0058) and B cells (p=0.017)) were higher in exposed versus control workers and findings were highly consistent when stratified by smoking status. In addition, there was evidence of an exposure-response relationship between elemental carbon and these end points (ptrends<0.05), and CD4+ T cell levels were significantly higher in the lowest tertile of DEE exposed workers compared to controls (p=0.012). CONCLUSIONS: Our results suggest that DEE exposure is associated with higher levels of cells that play a key role in the inflammatory process, which is increasingly being recognised as contributing to the aetiology of lung cancer. IMPACT: This study provides new insights into the underlying mechanism of DEE carcinogenicity.


Assuntos
Poluentes Ocupacionais do Ar , Linfócitos B/metabolismo , Neoplasias Pulmonares/etiologia , Subpopulações de Linfócitos/metabolismo , Exposição Ocupacional/efeitos adversos , Linfócitos T/metabolismo , Emissões de Veículos , Adulto , Poluentes Ocupacionais do Ar/análise , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Carbono/análise , Carcinógenos/análise , Estudos Transversais , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Neoplasias Pulmonares/metabolismo , Pessoa de Meia-Idade , Veículos Automotores , Exposição Ocupacional/análise , Medição de Risco , Emissões de Veículos/análise
16.
J Org Chem ; 79(14): 6480-9, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24949892

RESUMO

A series of symmetrical donor-acceptor-donor (D-A-D) chromophores bearing various electron-withdrawing groups, such as quinoxaline (Qx), benzo[g]quinoxaline (BQ), phenazine (Pz), benzo[b]phenazine (BP), thieno[3,4-b]pyrazine (TP), and thieno[3,4-b]quinoxaline (TQ), has been designed and synthesized. Intramolecular charge transfer (ICT) interactions can be found for all the chromophores due to the electron-withdrawing properties of the two imine nitrogens in the pyrazine ring and the electron-donating properties of the other two amine nitrogens in the two triphenylamines. Upon the fusion of either benzene or thiophene ring on the pyrazine acceptor unit, the ICT interactions are strengthened, which results in the bathochromically shifted ICT band. Moreover, the thiophene ring is superior to the benzene ring in enlarging the ICT interaction and expanding the absorption spectrum. Typically, when a thiophene ring is fused on the Qx unit in DQxD, a near-infrared dye is realized in simple chromophore DTQD, which displays the maximum absorption wavelength at 716 nm with the threshold over 900 nm. This is probably due to the enhanced charge density on the acceptor moiety and better orbital overlap, as revealed by theoretical calculation. These results suggest that extending the conjugation of a pyrazine acceptor in an orthogonal direction to the D-A-D backbone can dramatically improve the ICT interactions.

17.
Part Fibre Toxicol ; 11: 73, 2014 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-25497989

RESUMO

BACKGROUND: Although major concerns exist regarding the potential consequences of human exposures to nanoscale carbon black (CB) particles, limited human toxicological data is currently available. The purpose of this study was to evaluate if nanoscale CB particles could be responsible, at least partially, for the altered lung function and inflammation observed in CB workers exposed to nanoscale CB particles. METHODS: Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Brunauer-Emmett-Teller were used to characterize CB. Eighty-one CB-exposed male workers and 104 non-exposed male workers were recruited. The pulmonary function test was performed and pro-inflammatory cytokines were evaluated. To further assess the deposition and pulmonary damage induced by CB nanoparticles, male BALB/c mice were exposed to CB for 6 hours per day for 7 or 14 days. The deposition of CB and the pathological changes of the lung tissue in mice were evaluated by paraffin sections and TEM. The cytokines levels in serum and lung tissue of mice were evaluated by ELISA and immunohistochemical staining (IHC). RESULTS: SEM and TEM images showed that the CB particles were 30 to 50 nm in size. In the CB workplace, the concentration of CB was 14.90 mg/m³. Among these CB particles, 50.77% were less than 0.523 micrometer, and 99.55% were less than 2.5 micrometer in aerodynamic diameter. The reduction of lung function parameters including FEV1%, FEV/FVC, MMF%, and PEF% in CB workers was observed, and the IL-1ß, IL-6, IL-8, MIP-1beta, and TNF- alpha had 2.86-, 6.85-, 1.49-, 3.35-, and 4.87-folds increase in serum of CB workers, respectively. In mice exposed to the aerosol CB, particles were deposited in the lung. The alveolar wall thickened and a large amount of inflammatory cells were observed in lung tissues after CB exposure. IL-6 and IL-8 levels were increased in both serum and lung homogenate. CONCLUSIONS: The data strongly suggests that nanoscale CB particles could be responsible for the lung function reduction and pro-inflammatory cytokines secretion in CB workers. These results, therefore, provide the first evidence of a link between human exposure to CB and long-term pulmonary effects.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Citocinas/sangue , Exposição por Inalação/efeitos adversos , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Pneumonia/induzido quimicamente , Fuligem/toxicidade , Adulto , Poluentes Ocupacionais do Ar/química , Poluição do Ar em Ambientes Fechados/efeitos adversos , Animais , Câmaras de Exposição Atmosférica , Indústria Química , China , Citocinas/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/fisiopatologia , Pulmão/ultraestrutura , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Doenças Profissionais/metabolismo , Doenças Profissionais/patologia , Doenças Profissionais/fisiopatologia , Tamanho da Partícula , Pneumonia/metabolismo , Pneumonia/patologia , Pneumonia/fisiopatologia , Poli-Inos/síntese química , Embalagem de Produtos , Distribuição Aleatória , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/fisiopatologia , Mucosa Respiratória/ultraestrutura , Fuligem/administração & dosagem , Fuligem/química , Testes de Toxicidade Subaguda , Recursos Humanos
18.
Wei Sheng Yan Jiu ; 43(2): 193-7, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-24868967

RESUMO

OBJECTIVE: To investigate the roles of p53 in the interaction of p21, cyclin D1 and CDK4 in human embryonic lung fibroblasts (HELFs) induced by benzo (a) pyrene. METHODS: p53-H group (cells transfected with p53 small interference RNA plasmid, p53 siRNA) and HELF/CMV group (cells transfected with CMV vector) were treated with 2 micromol/L B [a] P for 24 h, and HELF/CMV + PFT-alpha group (HELF/CMV cells were treated with p53 chemical inhibitor, Pifithrin-alpha) was treated with 2 micromol/L B [a] P and 20 micromol/L PFT-alpha for 24 h. The above three groups set up control groups, respectively. Western blot assay was used to check the levels of p53, phosphorylated p53 at 20 site (p53-ser20), p21, cyclin D1 and CDK4. Immunoprecipitation assay was used to investigate the roles of p53 in the interaction of p21, cyclin D1 and CDK4. RESULTS: After inhibition of p53 using PFT-alpha or siRNA, the high levels of p53, p53-ser 20 and p21 induced by B [a] P were markedly decreased. The change of cyclin D1 level was not obsevered and the level CDK4 was free of B [a] P. The combination of p21 and CDK 4 was increased after HELFs exposed to B [a] P, which can not be observed after inhibition p53. The combination of p21 and cyclin D1 was increased with or without the expression of p53 after HELFs exposed to B [a] P. The combination of cyclin D1 and CDK 4 was not affected by B [a] P. CONCLUSION: p53 can affect the combination of p21 and CDK4 in HELFs induced by B [a] P.


Assuntos
Benzo(a)pireno/toxicidade , Proteínas de Ciclo Celular , Inibidor de Quinase Dependente de Ciclina p21 , Proteína Supressora de Tumor p53 , Benzotiazóis , Ciclo Celular , Ciclina D1 , Quinase 4 Dependente de Ciclina , Fibroblastos , Humanos , Pulmão , RNA Interferente Pequeno , Tolueno/análogos & derivados , Transfecção
19.
Wei Sheng Yan Jiu ; 43(2): 198-202, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-24868968

RESUMO

OBJECTIVE: To investigate the roles of ceruloplasmin (Cp) in JNK/ERK/ AP-1 cell signaling pathway change in human embryonic lung fibroblasts (HELFs) induced by silica. METHODS: Cp stimulated HELFs in different time points (before 1 h, accompanied with or after 1 h of silica-adding). HELFs were divided into these groups: control group, silica(100 microg/ml for 24 h) group, Cp (30 microg/ml for 24 h) group and silica plus Cp (100 microg/ml silica plus 30 microg/ml Cp) group. DN-JNK cells and DN-ERK cells (cells were transfected with dominant negative mutant plasmid) contained these groups: control group, silica group, silica plus Cp group. MTT assay was used to detect the effects of Cp on silica-induced cell proliferation. Western blot assay was performed to detect the levels of JNK, ERK, c-Jun, c-Fos and their phosphorylated levels. RESULTS: Cp promoted cell proliferation induced by silica when silica stimulated HELFs 1 h then adding to Cp. Cp significantly increased silica-induced the high levels of JNK, ERK and phosphorylated JNK (p-JNK), p-ERK, p-c-Jun and p-c-fos protein. After inhibition of JNK or ERK, silica-and-Cp-induced cell proliferation was markedly decreased. When suppressing JNK protein, the increased levels of p-JNK, p-c-Jun and p-c-fos protein was not observed. The high levels of p-ERK, p-c-Jun and p-c-fos protein were decreased when inhibiting ERK protein. CONCLUSION: Cp could further strengthen silica-induced cell proliferation by JNK/c-Jun/c-Fos and ERK/c-Jun cell signaling pathway.


Assuntos
Ceruloplasmina/fisiologia , Sistema de Sinalização das MAP Quinases , Transdução de Sinais , Dióxido de Silício/toxicidade , Comunicação Celular , Proliferação de Células , Células Cultivadas , Fibroblastos , Humanos , Pulmão , Oxirredução , Fosforilação , Proteínas Proto-Oncogênicas c-fos , Fator de Transcrição AP-1
20.
Wei Sheng Yan Jiu ; 43(3): 378-81, 404, 2014 May.
Artigo em Zh | MEDLINE | ID: mdl-24964613

RESUMO

OBJECTIVE: To explore the roles of ceruloplasmin (Cp) in histone modifications in human embryonic lung fibroblasts (HELFs) induced silica and the effects of phosphatase and tension homolog deleted on chromosome ten (PTEN) in this process. METHODS: HELFs were exposed to different concentrations of silica (50, 100, 200 microg/ ml) or Cp (10, 20, 30 microg/ml) for 24 h, and the level of protein lysine acetylation, of histone H2, H3 and H4 acetylation and histone H3 methylation were checked by werstern blot assay. HELFs and cells transfected with PTEN shRNA (PT) were treated with 200 microg/ml silica for 1 h, then added 30 microg/ml Cp for 24 h. Acetylation levels of protein lysine, histone H2, H3, H4 and methylation level of histone H3 were detected by werstern blot assay. RESULTS: Silica could induce the high level of protein lysine acetylation and acetyl-histone H2B (lys5/12), acetyl-histone H3 (lys9/14), acetyl-histone H4 (lys12) and the low level of methyl-histone (arg2), which could be reversed by Cp, in no exception for acetyl-histone H2B (lys5/12). Cp couldn't reverse histone modifications induced by silica when inhibited PTEN. CONCLUSION: Cp could reverse silica-induced the change of histone acetylation and histone methylation, and PTEN involved in this process.


Assuntos
Ceruloplasmina , PTEN Fosfo-Hidrolase , Dióxido de Silício/farmacologia , Acetilação , Fibroblastos , Histonas , Humanos , Lisina , Metilação , Oxirredução , Proteínas
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