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1.
Environ Int ; 185: 108521, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38508052

RESUMO

Electronic cigarettes (e-cigarettes) have rapidly gained popularity as alternatives to traditional combustible cigarettes. However, their long-term health impact remains uncertain. This study aimed to investigate the effects of chronic exposure to e-cigarette aerosol (ECA) in mice compared to conventional cigarette smoke (CS) exposure. The mice were exposed to air (control), low, medium, or high doses of ECA, or a reference CS dose orally and nasally for eight months. Various cardiovascular and pulmonary assessments have been conducted to determine the biological and prosthetic effects. Histopathological analysis was used to determine structural changes in the heart and lungs. Biological markers associated with fibrosis, inflammation, and oxidative stress were investigated. Cardiac proteomic analysis was applied to reveal the shared and unique protein expression changes in ECA and CS groups, which related to processes such as immune activation, lipid metabolism, and intracellular transport. Overall, chronic exposure to ECA led to adverse cardiovascular and pulmonary effects in mice, although they were less pronounced than those of CS exposure. This study provides evidence that e-cigarettes may be less harmful than combustible cigarettes for the long-term health of the cardiovascular and respiratory systems in mice. However, further human studies are needed to clarify the long-term health risks associated with e-cigarette use.


Assuntos
Fumar Cigarros , Sistemas Eletrônicos de Liberação de Nicotina , Animais , Humanos , Camundongos , Aerossóis/toxicidade , Pulmão , Proteômica
2.
ACS Appl Mater Interfaces ; 15(48): 55984-55990, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37993976

RESUMO

The characteristic of self-recovery holds significant implications for upholding performance stability within flexible electronic devices following the release of mechanical deformation. Herein, the dynamics of self-recovery in a buckling inorganic membrane is studied via in situ scanning probe microscopy technology. The experimental results demonstrate that the ultimate deformation ratio of the buckling BaTiO3 ferroelectric membrane is up to 88%, which is much higher than that of the buckling SrTiO3 dielectric membrane (49%). Combined with piezoresponse force microscopy and phase-field simulations, we find that ferroelectric domain transformation accompanies the whole process of buckling and self-recovery of the ferroelectric membrane, i.e., the presence of the nano-c domain not only releases part of the elastic energy of the membrane but also reduces the interface mismatch of the a/c domain, which encourages the buckling ferroelectric membrane to have excellent self-recovery properties. It is conceivable that the evolution of ferroelectric domains will play a greater role in the regulation of the mechanical properties of ferroelectric membranes and flexible devices.

3.
Biomed Pharmacother ; 165: 115105, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37399718

RESUMO

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity worldwide. Cigarette smoking, which leads to abnormalities in the airways or alveoli and persistent obstruction of the airway's flow, is a significant risk factor of COPD. Cryptotanshinone (CTS) is the active ingredient in Salvia miltiorrhiza (Danshen) and has many pharmacological properties including anti-inflammatory, antitumor, and antioxidant properties, but its impact on COPD is uncertain. In the present study, the potential effect of CTS on COPD was investigated in a modified COPD mice model induced with cigarette smoke (CS) and lipopolysaccharide (LPS) exposure. CTS significantly reversed the decline in lung function, emphysema, inflammatory cell infiltration, small airway remodeling, pulmonary pathological damage, and airway epithelial cell proliferation in CS- and LPS-exposed mice. Additionally, CTS decreased inflammatory cytokines such as tumor necrosis factor α (TNF α), interleukins IL-6 and IL-1ß, and keratinocyte chemoattractant (KC), increased the activities of superoxide dismutase (SOD), Catalase (CAT) and L-Glutathione (GSH), and repressed the expression of protein hydrolases matrix metalloprotein (MMP)- 9 and - 12 in pulmonary tissue and bronchoalveolar lavage fluid (BALF). The protective effects of CTS were also observed in human bronchial epithelial cell line BEAS-2B simulated with cigarette smoke condensate (CSC) and LPS. Mechanistically, CTS can repress the protein level of Keap1, resulting to activation of erythroid 2-related factor (Nrf2), finally alleviating COPD. In summary, the present findings demonstrated that CTS dramatically ameliorates COPD induced by CS and LPS via activating Keap1/Nrf2 pathway.


Assuntos
Fumar Cigarros , Doença Pulmonar Obstrutiva Crônica , Camundongos , Humanos , Animais , Lipopolissacarídeos/efeitos adversos , Fator 2 Relacionado a NF-E2/metabolismo , Fumar Cigarros/efeitos adversos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Pulmão , Glutationa/metabolismo
4.
BMC Public Health ; 23(1): 438, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882716

RESUMO

BACKGROUND: There is an increase in the use of cigarettes and e-cigarettes worldwide, and the similar trends may be observed in young adults. Since 2014, e-cigarettes have become the most commonly used nicotine products among young adults (Sun et al., JAMA Netw Open 4:e2118788, 2021). With the increase in e-cigarette use and the decrease in use of cigarettes and other tobacco products, however, there is limited information about Chinese smokers, e-cigarettes users and trends in cigarettes and e-cigarettes use among university students. Therefore, our objective was to investigate the using status of cigarettes, e-cigarettes and smoking behavior among the students from 7 universities in Guangzhou, China. METHODS: Students at 7 different universities in Guangzhou were investigated online in 2021 through a cross-sectional survey. A total of 10,008 students were recruited and after screening, 9361 participants were adopted in our statistics. Descriptive analysis, Chi-square analysis, and multiple logistic regression analysis were used to explore the smoking status and influencing factors. RESULTS: The average age of the 9361 university students was 22.4 years (SD = 3.6). 58.3% of participants were male. 29.8% of the participants smoked or used e-cigarettes. Among the smokers and users of e-cigarettes, 16.7% were e-cigarettes only users, 35.0% were cigarettes only users, and 48.3% were dual users. Males were more likely to smoke or use e-cigarettes. Medical students, students from prestigious Chinese universities, and students with higher levels of education were less likely. Students with unhealthy lifestyles (e.g., drinking alcohol frequently, playing video games excessively, staying up late frequently) were more likely to smoke or use e-cigarettes. Emotion can have significant impacts on both cigarettes and e-cigarettes dual users when choosing cigarettes or e-cigarettes to use. More than half of dual users said they would choose cigarettes when they were depressed and e-cigarettes when they were happy. CONCLUSION: We identified factors influencing the use of cigarettes and e-cigarettes among university students in Guangzhou, China. Gender, education level background, specialization, lifestyle habits and emotion all influenced the use of cigarettes and e-cigarettes among university students in Guangzhou, China. Male, low education level, from non-prestigious Chinese universities or vocational schools, non-medical specialization, and presence of unhealthy lifestyles were influencing factors for the use of cigarettes and e-cigarettes among university students in Guangzhou and students with these factors were more likely to smoke or use e-cigarettes. Besides, emotions can influence dual users' choice of products. This study provides more information to better understand young people's preferences for cigarettes and e-cigarettes by elucidating the characteristics of cigarettes and e-cigarettes use, as well as related influencing factors, among university students in Guangzhou. Further research involving more variables connected to the use of cigarettes and e-cigarettes will be required in our future study.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Adulto Jovem , Humanos , Masculino , Adolescente , Adulto , Feminino , Estudos Transversais , Universidades , China/epidemiologia , Estudantes , Fumar/epidemiologia
5.
Arch Toxicol ; 96(12): 3331-3347, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36173423

RESUMO

Combustible cigarettes produce many toxic substances that have been linked to diseases, such as lung cancer and chronic obstructive pulmonary disease. For those smokers unable or unwilling to quit, electronic cigarettes (e-cigarettes) could be used as an alternative to cigarettes. However, the effects and mechanisms of e-cigarette aerosol (ECA) on respiratory function have not been fully elucidated, and in vivo studies of its safety are limited compared to cigarette smoke (CS). In this article, we chose nicotine levels as dosing references and C57BL/6 mice for a 10-week subchronic inhalation toxicity study. A comprehensive set of toxicological endpoints was used to study the effect of exposure. Both CS (6 mg/kg) and ECA (6 or 12 mg/kg) inhalation had decreased the animal's lung function and increased levels of inflammation markers, along with pathological changes in the airways and lungs, with ECA displaying a relatively small effect at the same dose. Proteomic analysis of lung tissue showed greater overall protein changes by CS than that of ECA, with more severe inflammatory network perturbations. Compared with ECA, KEGG analysis of CS revealed upregulation of more inflammatory and virus-related pathways. Protein-protein interactions (PPI) showed that both ECA and CS significantly changed ribosome and complement system-related proteins in mouse lung tissue. The results support that e-cigarette aerosol is less harmful to the respiratory system than cigarette smoke at the same dose using this animal model, thus providing additional evidence for the relative safety of e-cigarettes.


Assuntos
Fumar Cigarros , Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Camundongos , Animais , Nicotina/análise , Proteômica , Camundongos Endogâmicos C57BL , Aerossóis e Gotículas Respiratórios , Produtos do Tabaco/toxicidade , Pulmão
6.
Phys Chem Chem Phys ; 22(10): 5819-5825, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32107521

RESUMO

The negative differential resistance (NDR) effect enables multilevel storage and gradual resistance modulation in resistive switching (RS) devices to be achieved. However, the poor reproducibility of NDR is the obstacle that restricts their application because the appearance of the NDR effect in RS devices is usually accidental or unstable at room temperature. In this report, we demonstrate a polarization and interfacial defect modulated NDR effect in h-LuFeO3/CoFe2O4 heterojunction-based RS devices; especially, the NDR is reproducible after hundreds of cycles at room temperature. This research provides an effective way for realizing the reproducible NDR effect in ferroelectric RS devices, and it may promote the development and application of RS devices with the NDR effect.

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