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1.
J Colloid Interface Sci ; 645: 533-541, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37163799

RESUMO

Catalytic oxidation technology is currently considered as a feasible approach to degrade and mineralize volatile organic compounds (VOCs). However, it is still challenging to realize efficient removal of VOCs through catalytic oxidation at room temperature. In our study, a novel flow-through electrocatalytic reactor was designed, composed of porous solid-electrolyte, gas-permeable titanium sub-oxides/titanium-foam (TiSO/Ti-foam) as anode and platinum coated titanium foam (Pt/Ti-foam) as cathode. This device could oxidize nearly 100% of benzene (10 ppm) to carbon dioxide at a current density of 1.2 mA/cm2 under room temperature. More importantly, the device maintained excellent stability over 1000 h. Mechanism of benzene mineralization was discussed. Hydroxyl radicals generated on the TiSO/Ti-foam anode played a crucial role in the oxidation of benzene. This study provides a promising prototype of the electrochemical air purifier, and may find its application in domestic and industrial air pollution control.

2.
Geroscience ; 44(3): 1215-1228, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34862585

RESUMO

Long-term exercise training has been considered as an effective strategy to counteract age-related hormonal declines and minimise muscle atrophy. However, human data relating circulating hormone levels with motor nerve function are scant. The aims of the study were to explore associations between circulating sex hormone levels and motor unit (MU) characteristics in older men, including masters athletes competing in endurance and power events. Forty-three older men (mean ± SD age: 69.9 ± 4.6 years) were studied based on competitive status. The serum concentrations of dehydroepiandrosterone (DHEA), total testosterone (T) and estradiol were quantified using liquid chromatography mass spectrometry. Intramuscular electromyographic signals were recorded from vastus lateralis (VL) during 25% of maximum voluntary isometric contractions and processed to extract MU firing rate (FR), and motor unit potential (MUP) features. After adjusting for athletic status, MU FR was positively associated with DHEA levels (p = 0.019). Higher testosterone and estradiol were associated with lower MUP complexity; these relationships remained significant after adjusting for athletic status (p = 0.006 and p = 0.019, respectively). Circulating DHEA was positively associated with MU firing rate in these older men. Higher testosterone levels were associated with reduced MUP complexity, indicating reduced electrophysiological temporal dispersion, which is related to decreased differences in conduction times along axonal branches and/or MU fibres. Although evident in males only, this work highlights the potential of hormone administration as a therapeutic interventional strategy specifically targeting human motor units in older age.


Assuntos
Hormônios Esteroides Gonadais , Testosterona , Idoso , Desidroepiandrosterona , Eletromiografia/métodos , Estradiol , Humanos , Masculino
3.
Lab Invest ; 101(4): 450-462, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32829381

RESUMO

Radiomics has potential advantages in the noninvasive histopathological and molecular diagnosis of gliomas. We aimed to develop a novel image signature (IS)-based radiomics model to achieve multilayered preoperative diagnosis and prognostic stratification of gliomas. Herein, we established three separate case cohorts, consisting of 655 glioma patients, and carried out a retrospective study. Image and clinical data of three cohorts were used for training (N = 188), cross-validation (N = 411), and independent testing (N = 56) of the IS model. All tumors were segmented from magnetic resonance (MR) images by the 3D U-net, followed by extraction of high-throughput network features, which were referred to as IS. IS was then used to perform noninvasive histopathological diagnosis and molecular subtyping. Moreover, a new IS-based clustering method was applied for prognostic stratification in IDH-wild-type lower-grade glioma (IDHwt LGG) and triple-negative glioblastoma (1p19q retain/IDH wild-type/TERTp-wild-type GBM). The average accuracies of histological diagnosis and molecular subtyping were 89.8 and 86.1% in the cross-validation cohort, while these numbers reached 83.9 and 80.4% in the independent testing cohort. IS-based clustering method was demonstrated to successfully divide IDHwt LGG into two subgroups with distinct median overall survival time (48.63 vs 38.27 months respectively, P = 0.023), and two subgroups in triple-negative GBM with different median OS time (36.8 vs 18.2 months respectively, P = 0.013). Our findings demonstrate that our novel IS-based radiomics model is an effective tool to achieve noninvasive histo-molecular pathological diagnosis and prognostic stratification of gliomas. This IS model shows potential for future routine use in clinical practice.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Aprendizado Profundo , Glioma/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/patologia , Feminino , Glioma/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Prognóstico , Estudos Retrospectivos , Adulto Jovem
4.
J Biol Dyn ; 13(1): 733-748, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31532345

RESUMO

In this paper, we consider a system of delay differential equations that models the oncolytic virotherapy on solid tumours with the delay of viral infection in the presence of the innate immune response. We conduct qualitative and numerical analysis, and provide possible medical implications for our results. The system has four equilibrium solutions. Fixed point analysis indicates that increasing the burst size and infection rate of the viruses has positive contribution to the therapy. However, increasing the immune killing infection rate, the immune stimulation rate, or the immune killing virus rate may lead the treatment failed. The viral infection time delay induces backward Hopf bifurcations, which means that the therapy may fail before time delay increases passing through a Hopf bifurcation. The parameter analysis also shows how saddle-node and Hopf bifurcations occur as viral burst size and other parameters vary, which yields further insights into the dynamics of the virotherapy.


Assuntos
Imunidade Inata , Modelos Teóricos , Terapia Viral Oncolítica , Vírus Oncolíticos/fisiologia , Simulação por Computador
5.
Yao Xue Xue Bao ; 37(5): 321-5, 2002 May.
Artigo em Chinês | MEDLINE | ID: mdl-12579832

RESUMO

AIM: To observe the stability of BCG-induced insulin resistance model. METHODS: The glucose tolerance, serum glucose, FFA, insulin, triglycerides, cholesterol, TNF-alpha and ALT level were measured. The change of GDR was measured by euglycemic clamp in model rats after given i.v. BCG 2, 4 and 8 weeks. RESULTS: After 2, 4 and 8 weeks, the GIR and glucose tolerance of the animals deceased significantly. After 2, 4 and 8 weeks, BCG infusion resulted in a pronounced reduction in glucose tolerance and insulin-stimulated glucose disposal rate [GDR = GDR: (29 +/- 6) vs (13 +/- 7) mg.kg-1.min-1 2 weeks; (29 +/- 6) vs (11 +/- 7) mg.kg-1.min-1 4 weeks and (23 +/- 3) vs (16 +/- 3) mg.kg-1.min-1 8 weeks, respectively, P < 0.01]. BCG infusion resulted in a pronounced increase in the weights of the liver [(6.2 +/- 0.9) vs (8.2 +/- 1.3) g, P < 0.05] and spleens [(0.51 +/- 0.11) vs (1.4 +/- 0.4) g, P < 0.01]. The histo-pathological results showed that BCG infusion resulted severe inflammation in the livers and spleens and the ratio of beta/alpha in pancreas increased. The serum levels of triglyceride, FFA and glucose were unchanged, but the level of serum TNF-alpha [543 +/- 60) vs (759 +/- 137) pg.mL-1, P < 0.05] and insulin [(31 +/- 5) vs (36 +/- 5) mu.L-1, P > 0.05] increased. CONCLUSION: This novel model of immune insulin resistance is completely and constantly established.


Assuntos
Resistência à Insulina/imunologia , Insulina/sangue , Fator de Necrose Tumoral alfa/metabolismo , Animais , Glicemia/metabolismo , Diabetes Mellitus/metabolismo , Técnica Clamp de Glucose , Teste de Tolerância a Glucose , Injeções Intravenosas , Masculino , Mycobacterium bovis , Distribuição Aleatória , Ratos , Ratos Wistar , Baço/patologia
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