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1.
BMC Med Inform Decis Mak ; 24(1): 17, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225576

RESUMO

BACKGROUND: Heart failure is a syndrome with complex clinical manifestations. Due to increasing population aging, heart failure has become a major medical problem worldwide. In this study, we used the MIMIC-III public database to extract the temporal and spatial characteristics of electrocardiogram (ECG) signals from patients with heart failure. METHODS: We developed a NYHA functional classification model for heart failure based on a deep learning method. We introduced an integrating attention mechanism based on the CNN-LSTM-SE model, segmenting the ECG signal into 2 to 20 s long segments. Ablation experiments showed that the 12 s ECG signal segments could be used with the proposed deep learning model for superior classification of heart failure. RESULTS: The accuracy, positive predictive value, sensitivity, and specificity of the NYHA functional classification method were 99.09, 98.9855, 99.033, and 99.649%, respectively. CONCLUSIONS: The comprehensive performance of this model exceeds similar methods and can be used to assist in clinical medical diagnoses.


Assuntos
Aprendizado Profundo , Insuficiência Cardíaca , Humanos , Arritmias Cardíacas/diagnóstico , Eletrocardiografia/métodos , Insuficiência Cardíaca/diagnóstico , Bases de Dados Factuais , Algoritmos
2.
Arch Orthop Trauma Surg ; 143(7): 4099-4109, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36183274

RESUMO

INTRODUCTION: Posterolateral approach has been advocated for the treatment of ankle fractures involving the posterior malleolus and satisfactory results were demonstrated in several studies. The Bartonicek classification based on 3-dimensional CT scanning was commonly used for treatment recommendation of posterior malleolar fracture (PMF). The aim of this retrospective study was to evaluate the clinical effect of the posterolateral approach for the treatment of PMF and present outcomes of patients with different types of Bartonicek classification. METHOD: We retrospectively reviewed the clinical outcomes of 72 patients with ankle fractures involving posterior malleolus (PM) from January 2016 to December 2018. Posterior malleolus fractures (PMFs) were all directly reduced and fixed by a posterolateral approach using lag screws and/or buttress plates. AOFAS score and VAS pain score were used as the primary functional outcome measures. The radiographic evaluation included the quality of the reduction and Kellgren-Lawrence (KL) osteoarthritis classification. According to the CT-based Bartonicek classification, all patients were classified into three groups: 42 type II, 18 type III and 12 type IV. Bartonicek type II patients were further divided into subtype IIa 19 cases, subtype IIb 16 cases and subtype IIc 7 cases. The radiological and functional outcomes were analyzed among different types and subtypes of Bartonicek classification. RESULTS: Sixty-eight patients (94.5%) achieved good or excellent reduction of PMF after surgery. The mean AOFAS score was 81.35 ± 6.15 at 6 months and 90.56 ± 4.98 at the final follow-up, respectively. The VAS score was 6.62 ± 1.03 one week after surgery, and 1.20 ± 0.92 at the final follow-up. Radiological evaluation at the final follow-up showed that primary bone union was achieved in all patients and 65 patients (88.9%) got no (KL grade 0) or just doubtable (KL grade 1) post-traumatic osteoarthritis. AOFAS scores decreased significantly with the severity of Bartonicek classification at 6 month (p < 0.001) and final follow-up (p < 0.05), while there was no statistical difference of VAS pain score among different types of Bartonicek classification. Reduction quality and the presence of osteoarthritis was not correlated to Bartonicek classification either. Besides, AOFAS scores at the final follow-up were statistically different among three subtypes of Bartonicek type II fractures (p < 0.05), and Bartonicek subtype IIa fractures had the highest AOFAS scores as 93 ± 4.99. Presence and severity of osteoarthritis was lower in patients with subtype IIa PMF compared to other subtype groups, this finding was statistically significant (p < 0.05). CONCLUSION: The posterolateral approach could achieve good clinical outcomes in the treatment of posterior malleolus fracture. Patients with a Bartonicek type II fracture had a better functional outcome measured by the AOFAS score compared to other types. Bartonicek type IIa fractures got a higher AOFAS score and a lower incidence of osteoarthritis at the final follow-up than the other two subtypes. Classification of PMFs according to the Bartonicek classification was reliable.


Assuntos
Fraturas do Tornozelo , Osteoartrite , Humanos , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Estudos Retrospectivos , Fixação Interna de Fraturas/métodos , Articulação do Tornozelo/cirurgia , Dor , Resultado do Tratamento
3.
Environ Res ; 212(Pt D): 113498, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35613629

RESUMO

Exposure to polycyclic aromatic hydrocarbons (PAHs) has been associated with systemic inflammation, yet what mechanisms regulate PAHs' inflammatory effects are less understood. This study evaluated the change of arachidonic acid (ARA) metabolites and inflammatory biomarkers in response to increased exposure to PAHs among 26 non-smoking healthy travelers from Los Angeles to Beijing. Traveling from Los Angeles to Beijing significantly increased urinary metabolites of dibenzofuran (800%), fluorene (568%), phenanthrene (277%), and pyrene (176%), accompanied with increased C-reactive protein, fibrinogen, IL-8, and IL-10, and decreased MCP-1, sCD40L, and sCD62P levels in the blood. Meanwhile, the travel increased the levels of ARA lipoxygenase metabolites that were positively associated with a panel of pro-inflammatory biomarkers. Concentrations of cytochrome P450 metabolite were also increased in Beijing and were negatively associated with sCD62P levels. In contrast, concentrations of ARA cyclooxygenase metabolites were decreased in Beijing and were negatively associated with anti-inflammatory IL-10 levels. Changes in both inflammatory biomarkers and ARA metabolites were reversed 4-7 weeks after participants returned to Los Angeles and were associated with urinary PAH metabolites, but not with other exposures such as secondhand smoke, stress, or diet. These results suggested possible roles of ARA metabolic alteration in PAHs-associated inflammatory effects.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Ácido Araquidônico , Biomarcadores/urina , Monitoramento Ambiental/métodos , Humanos , Interleucina-10 , Hidrocarbonetos Policíclicos Aromáticos/urina
4.
BMC Ophthalmol ; 21(1): 187, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33892678

RESUMO

BACKGROUND: Myopic maculopathy (MM) is one of the major causes of visual impairment and irreversible blindness in eyes with pathologic myopia (PM). However, the classification of each type of lesion associated with MM has not been determined. Recently, a new MM classification system, known as the ATN grading and classification system, was proposed; it is based on the fundus photographs and optical coherence tomography (OCT) images and includes three variable components: atrophy (A), traction (T), and neovascularization (N). This study aimed to perform an independent evaluation of interobserver and intraobserver agreement for the recently developed ATN grading system for MM. METHODS: This was a retrospective study. Fundus photographs and OCT images of 125 patients (226 eyes) with various MMs were evaluated and classified using the ATN grading of the new MM classification system by four blinded and independent evaluators (2 attending ophthalmologists and 2 ophthalmic residents). All cases were randomly re-evaluated by the same observers after an interval of 6 weeks. The kappa coefficient (κ) and 95% confidence interval (CI) were used to determine the interobserver and intraobserver agreement. RESULTS: The interobserver agreement was substantial when considering the maculopathy type (A, T, and N). The weighted Fleiss κ values for each MM type (A, T, and N) were 0.651 (95% CI: 0.602-0.700), 0.734 (95% CI: 0.689-0.779), and 0.702 (95% CI: 0.649-0.755), respectively. The interobserver agreement when considering the subtypes was good or excellent, except for stages A1, A2, and N1, in which the weighted κ value was less than 0.6, with moderate agreement. The intraobserver agreement of types and subtypes was excellent, with κ > 0.8. No significant differences were observed between the attending ophthalmologists and residents for interobserver reliability or intraobserver reproducibility. CONCLUSIONS: The ATN classification allows an adequate agreement among ophthalmologists with different qualifications and by the same observer on separate occasions. Future prospective studies should further evaluate whether this classification can be better implemented in clinical decision-making and disease progression assessments.


Assuntos
Degeneração Macular , Miopia , Humanos , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos
5.
Circulation ; 140(24): 1995-2004, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31744317

RESUMO

BACKGROUND: Exposure to air pollution increases cardiovascular morbidity and mortality. Preventing chronic cardiovascular diseases caused by air pollution relies on detecting the early effects of pollutants on the risk of cardiovascular disease development, which is limited by the lack of sensitive biomarkers. We have previously identified promising biomarkers in experimental animals but comparable evidence in humans is lacking. METHODS: Air pollution is substantially worse in Beijing than in Los Angeles. We collected urine and blood samples from 26 nonsmoking, healthy adult residents of Los Angeles (mean age, 23.8 years; 14 women) before, during, and after spending 10 weeks in Beijing during the summers of 2014 and 2015. We assessed a panel of circulating biomarkers indicative of lipid peroxidation and inflammation. Personal exposure to polycyclic aromatic hydrocarbons (PAHs), a group of combustion-originated air pollutants, was assessed by urinary PAH metabolite levels. RESULTS: Urinary concentrations of 4 PAH metabolites were 176% (95% CI, 103% to 276%) to 800% (95% CI, 509% to 1780%) greater in Beijing than in Los Angeles. Concentrations of 6 lipid peroxidation biomarkers were also increased in Beijing, among which 5-, 12-, and 15-hydroxyeicosatetraenoic acid and 9- and 13-hydroxyoctadecadienoic acid levels reached statistical significance (false discovery rate <5%), but not 8-isoprostane (20.8%; 95% CI, -5.0% to 53.6%). The antioxidative activities of paraoxonase (-9.8%; 95% CI, -14.0% to -5.3%) and arylesterase (-14.5%; 95% CI, -22.3% to -5.8%) were lower and proinflammatory C-reactive protein (101%; 95% CI, 3.3% to 291%) and fibrinogen (48.3%; 95% CI, 4.9% to 110%) concentrations were higher in Beijing. Changes in all these biomarkers were reversed, at least partially, after study participants returned to Los Angeles. Changes in most outcomes were associated with urinary PAH metabolites (P<0.05). CONCLUSIONS: Traveling from a less-polluted to a more-polluted city induces systemic pro-oxidative and proinflammatory effects. Changes in the levels of 5-, 12-, and 15-hydroxyeicosatetraenoic acid and 9- and 13-hydroxyoctadecadienoic acid as well as paraoxonase and arylesterase activities in the blood, in association with exposures to PAH metabolites, might have important implications in preventive medicine as indicators of increased cardiovascular risk caused by air pollution exposure.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Biomarcadores/sangue , Inflamação/etiologia , Material Particulado/análise , Adulto , Pequim , Proteína C-Reativa/metabolismo , Exposição Ambiental/análise , Feminino , Humanos , Los Angeles , Masculino , Estresse Oxidativo/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/análise , Adulto Jovem
6.
Arterioscler Thromb Vasc Biol ; 39(9): 1776-1786, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31340670

RESUMO

OBJECTIVE: Air pollution is associated with increased cardiovascular morbidity and mortality, as well as dyslipidemia and metabolic syndrome. Our goal was to dissect the mechanisms involved. Approach and Results: We assessed the effects of exposure to air pollution on lipid metabolism in mice through assessment of plasma lipids and lipoproteins, oxidized fatty acids 9-HODE (9-hydroxyoctadecadienoic) and 13-HODE (13-hydroxyoctadecadienoic), lipid, and carbohydrate metabolism. Findings were corroborated, and mechanisms were further assessed in HepG2 hepatocytes in culture. ApoE knockout mice exposed to inhaled diesel exhaust (DE, 6 h/d, 5 days/wk for 16 weeks) exhibited elevated plasma cholesterol and triglyceride levels, increased hepatic triglyceride content, and higher hepatic levels of 9-HODE and 13-HODE, as compared to control mice exposed to filtered air. A direct effect of DE exposure on hepatocytes was demonstrated by treatment of HepG2 cells with a methanol extract of DE particles followed by loading with oleic acid. As observed in vivo, this led to increased triglyceride content and significant downregulation of ACAD9 mRNA expression. Treatment of HepG2 cells with DE particles and oleic acid did not alter de novo lipogenesis but inhibited total, mitochondrial, and ATP-linked oxygen consumption rate, indicative of mitochondrial dysfunction. Treatment of isolated mitochondria, prepared from mouse liver, with DE particles and oleic acid also inhibited mitochondrial complex activity and ß-oxidation. CONCLUSIONS: DE exposure leads to dyslipidemia and liver steatosis in ApoE knockout mice, likely due to mitochondrial dysfunction and decreased lipid catabolism.


Assuntos
Fígado Gorduroso/induzido quimicamente , Hiperlipidemias/induzido quimicamente , Mitocôndrias/metabolismo , Emissões de Veículos/toxicidade , Animais , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Triglicerídeos/metabolismo
7.
J Biol Chem ; 292(3): 1112-1121, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-27986811

RESUMO

Eph receptors, the largest subfamily of transmembrane tyrosine kinase receptors, have been increasingly implicated in various physiologic and pathologic processes, and the roles of the Eph family members during tumorigenesis have recently attracted growing attentions. In the present study, we explored the function of EphB3, one member of Eph family, in papillary thyroid cancer (PTC). We found that the expression of EphB3 was significantly elevated in PTC. Either overexpression of EphB3 or activation of EphB3 by EfnB1-Fc/EfnB2-Fc stimulated in vitro migration of PTC cells. In contrast, siRNA-mediated knockdown of EphB3 or EphB3-Fc treatment, which only blocked EphB3-mediated forward signaling, inhibited migration and metastasis of PTC cells. A mechanism study revealed that EphB3 knockdown led to suppressed activity of Rac1 and enhanced activity of RhoA. Moreover, we found that Vav2, an important regulator of Rho family GTPases, was activated by EphB3 in a kinase-dependent manner. Altogether, our work suggested that EphB3 acted as a tumor promoter in PTC by increasing the in vitro migration as well as the in vivo metastasis of PTC cells through regulating the activities of Vav2 and Rho GTPases in a kinase-dependent manner.


Assuntos
Carcinoma/metabolismo , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-vav/metabolismo , Receptor EphB3/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Carcinoma/genética , Carcinoma/patologia , Carcinoma Papilar , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Metástase Neoplásica , Proteínas Proto-Oncogênicas c-vav/genética , Receptor EphB3/genética , Transdução de Sinais/genética , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Proteínas rac1 de Ligação ao GTP/genética
8.
Neuroimage ; 180(Pt B): 609-618, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29223740

RESUMO

Most neuroscience cognitive experiments involve repeated presentations of various stimuli across several minutes or a few hours. It has been observed that brain responses, even to the same stimulus, evolve over the course of the experiment. These changes in brain activation and connectivity are believed to be associated with learning and/or habituation. In this paper, we present two general approaches to modeling dynamic brain connectivity using electroencephalograms (EEGs) recorded across replicated trials in an experiment. The first approach is the Markovian regime-switching vector autoregressive model (MS-VAR) which treats EEGs as realizations of an underlying brain process that switches between different states both within a trial and across trials in the entire experiment. The second is the slowly evolutionary locally stationary process (SEv-LSP) which characterizes the observed EEGs as a mixture of oscillatory activities at various frequency bands. The SEv-LSP model captures the dynamic nature of the amplitudes of the band-oscillations and cross-correlations between them. The MS-VAR model is able to capture abrupt changes in the dynamics while the SEv-LSP directly gives interpretable results. Moreover, it is nonparametric and hence does not suffer from model misspecification. For both of these models, time-evolving connectivity metrics in the frequency domain are derived from the model parameters for both functional and effective connectivity. We illustrate these two models for estimating cross-trial connectivity in selective attention using EEG data from an oddball paradigm auditory experiment where the goal is to characterize the evolution of brain responses to target stimuli and to standard tones presented randomly throughout the entire experiment. The results suggest dynamic changes in connectivity patterns over trials with inter-subject variability.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Modelos Neurológicos , Modelos Estatísticos , Eletroencefalografia/métodos , Análise de Fourier , Humanos , Cadeias de Markov , Rede Nervosa/fisiologia , Vias Neurais/fisiologia
9.
Anticancer Drugs ; 29(6): 491-502, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29683800

RESUMO

The main aim of this study was to establish a novel paclitaxel (PTX)-resistant human gastric carcinoma cell line and to investigate its biological significance. A cell line, MGC803/PTX, was established by gradually increasing PTX density on the basis of MGC803 over a period of 10 months. In addition, a pair of resistant cell lines (SW620 and SW620/PTX) were added to further explain the resistant mechanism of PTX. The drug resistance index and stability of MGC803/PTX cells were detected using the Cell Counting Kit-8 method. The morphological features were observed using inverted microscopy. Apoptosis was measured by flow cytometry (FCM) and Hoechst 33258 fluorescence staining. The distribution of the cell cycle was determined by FCM, and protein expressions of P-gp, Bcl-2, Bax, and PARP were detected by western blot analysis. When characterizing the resistance in vitro, we found that MGC803/PTX cells were 10.3-fold more resistant to PTX compared with MGC803 cells. In addition, MGC803/PTX cells showed cross-resistance to 5-fluorouracil and adriamycin. FCM and Hoechst 33258 fluorescence staining indicated that MGC803/PTX cells had a significantly lower percentage of apoptotic cells after treatment with PTX compared with MGC803 cells. Other differences between parental cells and resistant cells included morphology, proliferation rate, doubling time, cell cycle distribution, and colony-formation rate. Western blot analysis indicated that P-gp, Bcl-2, and PARP protein were more abundant in MGC803/PTX and SW620/PTX cells compared with MGC803 and SW620 cells, whereas Bax protein levels were lower in resistant cells. Furthermore, MGC803/PTX cells showed obvious resistance to PTX in vivo. To our knowledge, this is the first report on the establishment of a PTX-resistant MGC803 cell line, which is an important tool to explore the resistance of anticancer drugs and to overcome tumor drug resistance.


Assuntos
Linhagem Celular Tumoral , Paclitaxel/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Distribuição Aleatória , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Part Fibre Toxicol ; 13(1): 26, 2016 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-27221567

RESUMO

BACKGROUND: Exposures to ambient particulate matter (PM) are associated with increased morbidity and mortality. PM2.5 (<2.5 µm) and ozone exposures have been shown to associate with carotid intima media thickness in humans. Animal studies support a causal relationship between air pollution and atherosclerosis and identified adverse PM effects on HDL functionality. We aimed to determine whether brief exposures to PM2.5 and/or ozone could induce effects on HDL anti-oxidant and anti-inflammatory capacity in humans. METHODS: Subjects were exposed to fine concentrated ambient fine particles (CAP) with PM2.5 targeted at 150 µg/m(3), ozone targeted at 240 µg/m(3) (120 ppb), PM2.5 plus ozone targeted at similar concentrations, and filtered air (FA) for 2 h, on 4 different occasions, at least two weeks apart, in a randomized, crossover study. Blood was obtained before exposures (baseline), 1 h after and 20 h after exposures. Plasma HDL anti-oxidant/anti-inflammatory capacity and paraoxonase activity were determined. HDL anti-oxidant/anti-inflammatory capacity was assessed by a cell-free fluorescent assay and expressed in units of a HDL oxidant index (HOI). Changes in HOI (ΔHOI) were calculated as the difference in HOI from baseline to 1 h after or 20 h after exposures. RESULTS: There was a trend towards bigger ΔHOI between PM2.5 and FA 1 h after exposures (p = 0.18) but not 20 h after. This trend became significant (p <0.05) when baseline HOI was lower (<1.5 or <2.0), indicating decreased HDL anti-oxidant/anti-inflammatory capacity shortly after the exposures. There were no significant effects of ozone alone or in combination with PM2.5 on the change in HOI at both time points. The change in HOI due to PM2.5 showed a positive trend with particle mass concentration (p = 0.078) and significantly associated with the slope of systolic blood pressure during exposures (p = 0.005). CONCLUSIONS: Brief exposures to concentrated PM2.5 elicited swift effects on HDL anti-oxidant/anti-inflammatory functionality, which could indicate a potential mechanism for how particulate air pollution induces harmful cardiovascular effects.


Assuntos
Poluição do Ar/efeitos adversos , Doenças Cardiovasculares/etiologia , Lipoproteínas HDL/sangue , Modelos Biológicos , Ozônio/toxicidade , Material Particulado/toxicidade , Saúde da População Urbana , Adulto , Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/imunologia , Estudos de Coortes , Estudos Cross-Over , Feminino , Humanos , Exposição por Inalação/efeitos adversos , Masculino , Oxidantes/química , Oxidantes/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Material Particulado/química , Risco , Método Simples-Cego , Adulto Jovem
12.
J Mater Sci Mater Med ; 26(1): 5348, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25578702

RESUMO

Novel water-soluble fullerene-glycine derivatives were synthesized by means of simple organic chemistry. They are completely soluble in water, yielding a clear brown solution. The products were characterized by fourier transform infrared (FTIR), ultraviolet-visible spectroscopy (UV-Vis), (1)H NMR, (13)C NMR, thermogravimetric analyses (TGA), and scanning electron microscopy (SEM). The assembly behavior of water-soluble fullerene-glycine derivatives was investigated by SEM. The results show that the fullerene-glycine derivatives create morphology that is sphere-like. The cytotoxicity to cancer cell lines of the fullerene-glycine derivatives was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and flow cytometry. The results show that fullerene-glycine derivatives exhibit mortality and apoptosis of the cells which increased with the increase of fullerene-glycine derivative concentration. The cytotoxicity mechanism of fullerene-glycine derivatives was investigated for the first time. Novel water-soluble fullerene-glycine derivatives were synthesized by means of simple organic chemistry. The products were characterized by FTIR, UV-Vis, (1)H NMR, (13)C NMR, TGA, and SEM. The bioactivities of fullerene-glycine derivative materials have been tested, and the results show that compared with the fullerene complex, the fullerene-glycine derivative materials exhibit mortality and apoptosis of the cells which increased with the increase of fullerene-glycine derivative concentration. SEM images showed the macrostructure of fullerene-glycine derivative materials was spheres.


Assuntos
Fulerenos/química , Glicina/química , Neoplasias/terapia , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Carbono/química , Linhagem Celular Tumoral , Desenho de Fármacos , Citometria de Fluxo , Glicina/síntese química , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Nanoestruturas/química , Solubilidade , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Água/química
13.
Arterioscler Thromb Vasc Biol ; 33(6): 1153-61, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23559632

RESUMO

OBJECTIVE: To evaluate whether exposure to air pollutants induces oxidative modifications of plasma lipoproteins, resulting in alteration of the protective capacities of high-density lipoproteins (HDLs). APPROACH AND RESULTS: We exposed apolipoprotein E-deficient mice to diesel exhaust (DE) at ≈ 250 µg/m(3) for 2 weeks, filtered air (FA) for 2 weeks, or DE for 2 weeks, followed by FA for 1 week (DE+FA). DE led to enhanced lipid peroxidation in the brochoalveolar lavage fluid that was accompanied by effects on HDL functionality. HDL antioxidant capacity was assessed by an assay that evaluated the ability of HDL to inhibit low-density lipoprotein oxidation estimated by 2',7'-dichlorofluorescein fluorescence. HDL from DE-exposed mice exhibited 23,053 ± 2844 relative fluorescence units, higher than FA-exposed mice (10,282 ± 1135 relative fluorescence units, P<0.001) but similar to the HDL from DE+FA-exposed mice (22,448 ± 3115 relative fluorescence units). DE effects on HDL antioxidant capacity were negatively correlated with paraoxonase enzymatic activity, but positively correlated with levels of plasma 8-isoprostanes, 12-hydroxyeicosatetraenoic acid, 13-hydroxyoctadecadienoic acid, liver malondialdehyde, and accompanied by perturbed HDL anti-inflammatory capacity and activation of the 5-lipoxygenase pathway in the liver. CONCLUSIONS: DE emissions induced systemic pro-oxidant effects that led to the development of dysfunctional HDL. This may be one of the mechanisms by which air pollution contributes to enhanced atherosclerosis.


Assuntos
Araquidonato 5-Lipoxigenase/metabolismo , Exposição por Inalação/efeitos adversos , Peroxidação de Lipídeos , Lipoproteínas HDL/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/metabolismo , Apolipoproteínas E/deficiência , Araquidonato 5-Lipoxigenase/genética , Arildialquilfosfatase/metabolismo , Modelos Animais de Doenças , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos , Distribuição Aleatória , Valores de Referência , Transdução de Sinais , Emissões de Veículos
14.
Inhal Toxicol ; 26(14): 861-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25472476

RESUMO

CONTEXT: Smoking is associated with increased fibrinogen and decreased paraoxonase (PON) activity, markers of inflammation and oxidative stress, in patients with coronary artery disease. OBJECTIVE: We tested the hypothesis that the adverse effect of smoking on these biomarkers of inflammation and oxidative stress would be detectable in otherwise healthy young female habitual smokers. MATERIALS AND METHODS: Thirty-eight young women participated in the study (n = 20 habitual smokers, n = 18 non-smokers). Fibrinogen, PON-1 activity and HDL oxidant index (HOI) were measured. RESULTS: Mean values of fibrinogen, PON-1 activity and log HOI were not different between the groups. Importantly, however, decreased PON-1 activity (rs = -0.51, p = 0.03) and increased fibrinogen (rs = 0.49, p = 0.04) were significantly correlated with increasing number of cigarettes smoked per day in habitual smokers. DISCUSSION AND CONCLUSION: Cigarette smoking is associated with a dose-dependent adverse effect on PON-1 activity and fibrinogen in young women, which may have implications for future cardiovascular risk.


Assuntos
Arildialquilfosfatase/metabolismo , Fibrinogênio/metabolismo , Fumar/efeitos adversos , Adulto , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/patologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Relação Dose-Resposta a Droga , Feminino , Humanos , Estresse Oxidativo/efeitos dos fármacos , Fatores de Risco , Adulto Jovem
15.
Inhal Toxicol ; 26(1): 23-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24417404

RESUMO

CONTEXT: High-density lipoprotein (HDL) particles perform numerous vascular-protective functions. Animal studies demonstrate that exposure to fine or ultrafine particulate matter (PM) can promote HDL dysfunction. However, the impact of PM on humans remains unknown. OBJECTIVE: We aimed to determine the effect of exposure to coarse concentrated ambient particles (CAP) on several metrics of HDL function in healthy humans. METHODS: Thirty-two adults (25.9 ± 6.6 years) were exposed to coarse CAP [76.2 ± 51.5 µg·m(-3)] in a rural location and filtered air (FA) for 2 h in a randomized double-blind crossover study. Venous blood collected 2- and 20-h post-exposures was measured for HDL-mediated efflux of [(3)H]-cholesterol from cells and 20-h exposures for HDL anti-oxidant capacity by a fluorescent assay and paraoxonase activity. The changes [median (first, third quartiles)] between exposures among 29 subjects with available results were compared by matched Wilcoxon tests. RESULTS: HDL-mediated cholesterol efflux capacity did not differ between exposures at either time point [16.60% (15.17, 19.19) 2-h post-CAP versus 17.56% (13.43, 20.98) post-FA, p = 0.768 and 14.90% (12.47, 19.15) 20-h post-CAP versus 17.75% (13.22, 23.95) post-FA, p = 0.216]. HOI [0.26 (0.24, 0.35) versus 0.28 (0.25, 0.40), p = 0.198] and paraoxonase activity [0.54 (0.39, 0.82) versus 0.60 µmol·min(-1 )ml plasma(-1) (0.40, 0.85), p = 0.137] did not differ 20-h post-CAP versus FA, respectively. CONCLUSIONS: Brief inhalation of coarse PM from a rural location did not acutely impair several facets of HDL functionality. Whether coarse PM derived from urban sites, fine particles or longer term PM exposures can promote HDL dysfunction warrant future investigations.


Assuntos
Poluentes Atmosféricos/toxicidade , Lipoproteínas HDL/sangue , Material Particulado/toxicidade , Adolescente , Adulto , Poluição do Ar/efeitos adversos , Animais , Arildialquilfosfatase/sangue , Linhagem Celular Tumoral , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Lipoproteínas HDL/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Tamanho da Partícula , População Rural , Adulto Jovem
16.
Int J Biol Macromol ; 257(Pt 1): 128605, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061508

RESUMO

Co-fermentation of multiple substrates has emerged as the most effective method to improve the yield of bioproducts. Herein, sustainable rubberwood enzymatic hydrolysates (RWH) were co-fermented by Aureobasidium pullulans to produce poly(ß-L-malic acid) (PMA), and RWH + glucose/xylose was also investigated as co-substrates. Owing to low inhibitor concentration and abundant natural nitrogen source content of RWH, a high PMA yield of 0.45 g/g and a productivity of 0.32 g/L/h were obtained by RWH substrate fermentation. After optimization, PMA yields following the fermentation of RWH + glucose and RWH + xylose reached 59.92 g/L and 53.71 g/L, respectively, which were 52 % and 36 % higher than that after the fermentation of RWH. RWH + glucose more significantly affected the correlation between PMA yield and substrate concentration than RWH + xylose. The results demonstrated that the co-fermentation of RWH co-substrate is a promising method for the synthesis of bioproducts.


Assuntos
Aureobasidium , Polímeros , Xilose , Fermentação , Polímeros/metabolismo , Malatos , Glucose
17.
Adv Sci (Weinh) ; : e2404272, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953411

RESUMO

The phenomenon of flexoelectricity, wherein mechanical deformation induces alterations in the electron configuration of metal oxides, has emerged as a promising avenue for regulating electron transport. Leveraging this mechanism, stress sensing can be optimized through precise modulation of electron transport. In this study, the electron transport in 2D ultra-smooth In2O3 crystals is modulated via flexoelectricity. By subjecting cubic In2O3 (c-In2O3) crystals to significant strain gradients using an atomic force microscope (AFM) tip, the crystal symmetry is broken, resulting in the separation of positive and negative charge centers. Upon applying nano-scale stress up to 100 nN, the output voltage and power values reach their maximum, e.g. 2.2 mV and 0.2 pW, respectively. The flexoelectric coefficient and flexocoupling coefficient of c-In2O3 are determined as ≈0.49 nC m-1 and 0.4 V, respectively. More importantly, the sensitivity of the nano-stress sensor upon c-In2O3 flexoelectric effect reaches 20 nN, which is four to six orders smaller than that fabricated with other low dimensional materials based on the piezoresistive, capacitive, and piezoelectric effect. Such a deformation-induced polarization modulates the band structure of c-In2O3, significantly reducing the Schottky barrier height (SBH), thereby regulating its electron transport. This finding highlights the potential of flexoelectricity in enabling high-performance nano-stress sensing through precise control of electron transport.

18.
Artigo em Inglês | MEDLINE | ID: mdl-39143699

RESUMO

This study emphasizes the innovative application of FePt and Cu core-shell nanostructures with increased lattice microstrain, coupled with Au single-atom catalysis, in significantly enhancing •OH generation for catalytic tumor therapy. The combination of core-shell with increased lattice microstrain and single-atom structures introduces an unexpected boost in hydroxyl radical (•OH) production, representing a pivotal advancement in strategies for enhancing reactive oxygen species. The creation of a core-shell structure, FePt@Cu, showcases a synergistic effect in •OH generation that surpasses the combined effects of FePt and Cu individually. Incorporating atomic Au with FePt@Cu/Au further enhances •OH production. Both FePt@Cu and FePt@Cu/Au structures boost the O2 → H2O2 → •OH reaction pathway and catalyze Fenton-like reactions. This enhancement is underpinned by DFT theoretical calculations revealing a reduced O2 adsorption energy and energy barrier, facilitated by lattice mismatch and the unique catalytic activity of single-atom Au. Notably, the FePt@Cu/Au structure demonstrates remarkable efficacy in tumor suppression and exhibits biodegradable properties, allowing for rapid excretion from the body. This dual attribute underscores its potential as a highly effective and safe cancer therapeutic agent.

19.
Circ Res ; 109(5): e27-41, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21737788

RESUMO

RATIONALE: Oxidized palmitoyl arachidonyl phosphatidylcholine (Ox-PAPC) accumulates in atherosclerotic lesions, is proatherogenic, and influences the expression of more than 1000 genes in endothelial cells. OBJECTIVE: To elucidate the major pathways involved in Ox-PAPC action, we conducted a systems analysis of endothelial cell gene expression after exposure to Ox-PAPC. METHODS AND RESULTS: We used the variable responses of primary endothelial cells from 149 individuals exposed to Ox-PAPC to construct a network that consisted of 11 groups of genes, or modules. Modules were enriched for a broad range of Gene Ontology pathways, some of which have not been identified previously as major Ox-PAPC targets. Further validating our method of network construction, modules were consistent with relationships established by cell biology studies of Ox-PAPC effects on endothelial cells. This network provides novel hypotheses about molecular interactions, as well as candidate molecular regulators of inflammation and atherosclerosis. We validated several hypotheses based on network connections and genomic association. Our network analysis predicted that the hub gene CHAC1 (cation transport regulator homolog 1) was regulated by the ATF4 (activating transcription factor 4) arm of the unfolded protein response pathway, and here we showed that ATF4 directly activates an element in the CHAC1 promoter. We showed that variation in basal levels of heme oxygenase 1 (HMOX1) contribute to the response to Ox-PAPC, consistent with its position as a hub in our network. We also identified G-protein-coupled receptor 39 (GPR39) as a regulator of HMOX1 levels and showed that it modulates the promoter activity of HMOX1. We further showed that OKL38/OSGN1 (oxidative stress-induced growth inhibitor), the hub gene in the blue module, is a key regulator of both inflammatory and antiinflammatory molecules. CONCLUSIONS: Our systems genetics approach has provided a broad view of the pathways involved in the response of endothelial cells to Ox-PAPC and also identified novel regulatory mechanisms.


Assuntos
Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Redes Reguladoras de Genes/fisiologia , Heme Oxigenase-1/fisiologia , Fosfatidilcolinas/fisiologia , Adulto , Aterosclerose/enzimologia , Aterosclerose/genética , Aterosclerose/patologia , Células Cultivadas , Endotélio Vascular/enzimologia , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes/genética , Humanos , Fosfatidilcolinas/genética
20.
Analyst ; 138(19): 5576-9, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-23912180

RESUMO

A new multisignaling molecular probe DFDB was designed for the selective detection of Zn(2+). DFDB can be synthesized by a simple one-step reaction in high yield. Theoretical calculation suggests a novel sandwich structure of the DFDB·Zn(2+) complex.

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