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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.
Comput Biol Med ; 170: 107917, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228030

RESUMO

In standard hospital blood tests, the traditional process requires doctors to manually isolate leukocytes from microscopic images of patients' blood using microscopes. These isolated leukocytes are then categorized via automatic leukocyte classifiers to determine the proportion and volume of different types of leukocytes present in the blood samples, aiding disease diagnosis. This methodology is not only time-consuming and labor-intensive, but it also has a high propensity for errors due to factors such as image quality and environmental conditions, which could potentially lead to incorrect subsequent classifications and misdiagnosis. Contemporary leukocyte detection methods exhibit limitations in dealing with images with fewer leukocyte features and the disparity in scale among different leukocytes, leading to unsatisfactory results in most instances. To address these issues, this paper proposes an innovative method of leukocyte detection: the Multi-level Feature Fusion and Deformable Self-attention DETR (MFDS-DETR). To tackle the issue of leukocyte scale disparity, we designed the High-level Screening-feature Fusion Pyramid (HS-FPN), enabling multi-level fusion. This model uses high-level features as weights to filter low-level feature information via a channel attention module and then merges the screened information with the high-level features, thus enhancing the model's feature expression capability. Further, we address the issue of leukocyte feature scarcity by incorporating a multi-scale deformable self-attention module in the encoder and using the self-attention and cross-deformable attention mechanisms in the decoder, which aids in the extraction of the global features of the leukocyte feature maps. The effectiveness, superiority, and generalizability of the proposed MFDS-DETR method are confirmed through comparisons with other cutting-edge leukocyte detection models using the private WBCDD, public LISC and BCCD datasets. Our source code and private WBCCD dataset are available at https://github.com/JustlfC03/MFDS-DETR.


Assuntos
Doenças Hematológicas , Trabalho de Parto , Piperazinas , Humanos , Gravidez , Feminino , Leucócitos , Hospitais
3.
Front Toxicol ; 5: 1232040, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37731664

RESUMO

Electronic cigarettes have become increasingly popular, but the results of previous studies on electronic cigarette exposure in animals have been equivocal. This study aimed to evaluate the effects of electronic cigarette smoke (ECS) and cigarette smoke (CS) on lung function and pulmonary inflammation in mice to investigate whether electronic cigarettes are safer when compared to cigarettes. 32 specific pathogen-free BALB/c male mice were randomly grouped and exposed to fresh air (control), mint-flavored ECS (ECS1, 6 mg/kg), cheese-flavored ECS (ECS2, 6 mg/kg), and CS (6 mg/kg). After 3 weeks exposure to ECS or CS, we measured lung function (PIF and Penh) and blood oxygen saturation. The levels of TNF-α and IL-6 in the bronchoalveolar lavage fluid (BALF) and serum were measured using ELISA. HE staining was performed to observe the pathological changes in the lung tissues. The levels of IL-6 in BALF and serum, and TNF-α in BALF, were elevated similarly in the ECS and CS groups compared to the control group. Significant elevation was observed in serum TNF-α levels in the CS group. The total count of cells in BALF were increased after ECS1 exposure and CS exposure. PIF and oxygen saturation decreased, and Penh increased markedly in the CS group but not in the ECS groups. Compared with the ECS groups, mice in the CS group had widened lung tissue septa and increased inflammatory cell infiltration. However, we did not detect significant differences between mint-flavored and cheese-flavored e-cigarettes in our study. Overall, our findings suggested that both ECS and CS impair lung function and histopathology while promoting inflammation. In contrast, ECS has a less negative impact than CS.

4.
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 , Nicotiana/efeitos adversos , Glutationa/metabolismo
5.
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
6.
Environ Pollut ; 290: 118002, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34419862

RESUMO

The influence of intercalated anions on the structure and composition of green rusts supplies a theoretical possibility for the investigation of the structural modification of FeII/FeIII (oxyhydr)oxide materials. ß-Cyclodextrin was intercalated into the mixed-valent iron-based hydroxide layers to synthesize new green rust materials (ß-CD GRs), pursuing high-capacity uraniumVI (UVI) sorption. The molar ratios of FeII to FeIII and the molar ratios of ß-CD GR to FeII + FeIII had a significant effect on the synthesis of ß-CD GRs. The synthesis process was further optimized by the quadric predictor and desirability function in a central composite design in combination. Both strong acidity and alkalinity were harmful to the adsorption of ß-CD GRs towards UVI. The pseudo-first-order kinetic model and Langmuir isotherm model were appropriate in fitting the whole adsorption process. The maximum monolayer adsorption capacity of ß-CD GRs was 2548.61 mg/g. The presence of mimic groundwater constituents explicitly deteriorated the interaction between ß-CD GR and UVI species. Nanoscale nodules and particles were formed on the ß-CD GR after the adsorption experiments. The peaks at 1159 and 609 cm-1 vanished with the band at 1103 cm-1 being left-shifted to 1117 cm-1 in the FTIR spectra of ß-CD GR during the heterogeneous process. The intercalation of ß-CD brought obvious enhancement of UVI species sorption to the GR material, which was combinedly driven by several reaction pathways and different from the unmodified GRs.


Assuntos
Urânio , beta-Ciclodextrinas , Adsorção , Compostos Férricos , Ferro , Cinética
7.
Opt Express ; 28(7): 9123-9135, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32225525

RESUMO

This work investigates the excitation of dense comb-like enhanced leaky mode resonance (eLMR) in tilted fiber Bragg grating (TFBG) integrated with indium tin oxide (ITO) nanocoating. The ITO overlay leads to a large reduction in mode loss and a great increase of propagation length for s-polarized leaky modes, which means the leaky modes become guided. The guidance of leaky modes enhances significantly the interaction with the core guided mode, which leads to the generation of strong dense comb-like eLMR. The results show that the ultra-narrow eLMR bands present promising sensing performance with an extended measurement range and provide advantages of high Q measurement over the case of surface plasmon resonance (SPR) and lossy mode resonance (LMR). The similarities and differences between the eLMR and SPR and LMR are also discussed. This study offers new opportunities to develop eLMR-based multifunctional fiber-optic devices with high performance.

8.
J Opt Soc Am A Opt Image Sci Vis ; 35(3): 397-405, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29522041

RESUMO

This work presents a sensitive refractive index sensor based on the dual resonance of an excessively tilted long period fiber grating (Ex-TLPFG). The Ex-TLPFG is tuned to couple the guided core mode with only the polarization-degenerate cladding mode LP1,l, which consists of TE/TM0,l and HE2,l vector modes. It is found that the p-polarized LP1,lp mode exhibits a higher sensitivity than that of the s-polarized LP1,ls mode. An optimized sensitivity as high as 12182.9 nm/RIU is achieved for the p-polarized LP1,2p mode at the low refractive index region by tuning the initial resonance condition. The sensing performance is also evaluated through the power measurement method for a single resonance band. It is demonstrated that the improved sensitivity in this work for diameter-reduced Ex-TLPFG is much higher than that for the conventional LPFG based devices, which makes this sensing platform very attractive for a variety of index sensing applications.

9.
J Opt Soc Am A Opt Image Sci Vis ; 35(2): 200-209, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29400874

RESUMO

A novel structure from motion (SfM) pipeline that combines point features and line features together is presented in this paper. Line segments usually are more difficult to handle than points in SfM due to the instability of their end points and the property of being unconstrained by epipolar geometry. Our proposed method first implements a very robust and efficient line segment matching by applying homography and optical flow tracking. Global homography and multiple homography schemes are combined to get a better effect. By virtue of sampling lines, line matching is converted to point matching. A unified global SfM pipeline is then available for both lines and points. In the end, the proposed method is evaluated through various datasets. The result shows that our line-based SfM can generate accurate 3D models with lines and give meaningful representation for a man-made environment.

10.
ISA Trans ; 69: 281-295, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28390653

RESUMO

For industrial processes, the state estimation plays a key role in various applications, such as process monitoring and model based control. Although the particle filter (PF) is able to deal with nonlinear and non-Gaussian processes, it rarely considers the influence of measurements with gross errors, such as outliers, biases and drifts. Nevertheless, measurements of dynamical systems are often influenced by different types of gross errors. This paper proposes a robust PF approach, in which gross error identification is used to estimate magnitudes of gross error. The gross errors can be removed or compensated so that a feasible set of particle sampling can contain the true states of the system. The proposed robust PF approach is implemented on a complex nonlinear dynamic system, the free radical polymerization of styrene. The application results show that the proposed approach is an appealing alternative to solving PF estimation problems with measurements containing gross errors.

11.
Opt Express ; 23(6): 8051-60, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25837143

RESUMO

An algorithm for calculating the field distribution of a high numerical aperture Fresnel zone plate (FZP) in stratified media is presented, which is based on the vector angular spectrum method. The diffraction problem of FZP is solved for the case of a multilayer film with planar interfaces perpendicular to the optical axis. The solution is obtained in a rigorous mathematical manner and it satisfies the homogeneous wave equations. The electric strength vector of the transmitted and reflected field in the multilayer media is obtained for any polarized beam normally incident onto a binary phase circular FZP. For radially-, azimuthally- and linearly-polarized beam, the electric field in the focal region can be simplified as double or single integral, which can be readily used for numerical computation.

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