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1.
Aging Clin Exp Res ; 36(1): 79, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38520484

RESUMO

BACKGROUND: Cardiometabolic multimorbidity (CM) has been found to be associated with higher mortality and functional limitations. However, few studies have investigated the longitudinal association between CM and disability in the Chinese population and whether these associations vary by smoking status. METHODS: The study included 16,754 participants from four waves (2011, 2013, 2015, and 2018) of China Health and Retirement Longitudinal Study (CHARLS) (mean age: 59, female: 51%). CM was assesed at baseline and defined as having two or more of diabetes, stroke, or heart disease. Disability was repeatedly measured by summing the number of impaired activities of daily living (ADL) and instrumental activities of daily living (IADL) during the 7-year follow-up. Linear mixed-effects model was used to determine the association of CM and trajectories of disability and to assess the modification effect of smoking status in these associations. RESULTS: Participants with CM at baseline had a faster progression of disability compared to those without CM (CM: ß = 0.13, 95% CI: 0.05 to 0.21). Current smokers with CM developed disability faster than their counterparts (Pinteraction for smoking=0.011). In addition, there was a significant association between CM and the annual change of disability in current smokers (ß = 0.34, 95% CI: 0.17 to 0.50) while no such association was observed in current non-smokers (ß = 0.08, 95% CI: -0.02 to 0.17). CONCLUSION: CM was associated with more a rapid disability progression. Notably, being current smokers may amplify the adverse effects of CM on disability progression.


Assuntos
Cardiopatias , Multimorbidade , Humanos , Feminino , Atividades Cotidianas , Estudos Longitudinais , Fumar/efeitos adversos , Fumar/epidemiologia , China/epidemiologia
2.
J Am Chem Soc ; 145(31): 17164-17175, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37440344

RESUMO

One of the hallmarks of multicomponent metal-organic frameworks (MOFs) is to finely tune their active centers to achieve product selectivity. In particular, obtaining bimetallic MOF hollow structures with precisely tailored redox centers under the same topology is still challenging despite a recent surge of such efforts. Herein, we present an engineering strategy named "cluster labilization" to generate hierarchically porous MOF composites with hollow structures and tunable active centers. By partially replacing zirconium with cerium in the hexanuclear clusters of UiO-66, unevenly distributed yolk-shell structures (YSS) were formed. Through acid treatment or annealing of the YSS precursor, single-shell hollow structures (SSHS) or double-shell hollow structures (DSHS) can be obtained, respectively. The active centers in SSHS and DSHS differ in their species, valence, and spatial locations. More importantly, YSS, SSHS, and DSHS with distinct active centers and microenvironments exhibit tunable catalytic activity, reversed selectivity, and high stability in the tandem reaction and the photoreaction.

3.
Eur J Nucl Med Mol Imaging ; 50(7): 2100-2113, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36807768

RESUMO

PURPOSE: Extradomain B of fibronectin (EDB-FN) is a promising diagnostic and therapeutic biomarker for thyroid cancer (TC). Here, we identified a high-affinity EDB-FN targeted peptide named EDBp (AVRTSAD) and developed three EDBp-based probes, Cy5-PEG4-EDBp(Cy5-EDBp), [18F]-NOTA-PEG4-EDBp([18F]-EDBp), and [177Lu]-DOTA-PEG4-EDBp ([177Lu]-EDBp), for the surgical navigation, radionuclide imaging, and therapy of TC. METHODS: Based on the previously identified EDB-FN targeted peptide ZD2, the optimized EDB-FN targeted peptide EDBp was identified by using the alanine scan strategy. Three EDBp-based probes, Cy5-EDBp, [18F]-EDBp, and [177Lu]-EDBp, were developed for fluorescence imaging, positron emission tomography (PET) imaging, and radiotherapy in TC tumor-bearing mice, respectively. Additionally, [18F]-EDBp was evaluated in two TC patients. RESULTS: The binding affinity of EDBp to the EDB fragment protein (Kd = 14.4 ± 1.4 nM, n = 3) was approximately 336-fold greater than that of the ZD2 (Kd = 4839.7 ± 361.7 nM, n = 3). Fluorescence imaging with Cy5-EDBp facilitated the complete removal of TC tumors. [18F]-EDBp PET imaging clearly delineated TC tumors, with high tumor uptake (16.43 ± 1.008%ID/g, n = 6, at 1-h postinjection). Radiotherapy with [177Lu]-EDBp inhibited tumor growth and prolonged survival in TC tumor-bearing mice (survival time of different treatment groups: saline vs. EDBp vs. ABRAXANE vs. [177Lu]-EDBp = 8.00 d vs. 8.00 d vs. 11.67 d vs. 22.33 d, ***p < 0.001). Importantly, the first-in-human evaluation of [18F]-EDBp demonstrated that it had specific targeting properties (SUVmax value of 3.6) and safety. CONCLUSION: Cy5-EDBp, [18F]-EDBp, and [177Lu]-EDBp are promising candidates for the surgical navigation, radionuclide imaging, and radionuclide therapy of TC, respectively.


Assuntos
Cirurgia Assistida por Computador , Neoplasias da Glândula Tireoide , Humanos , Animais , Camundongos , Fibronectinas/metabolismo , Tomografia por Emissão de Pósitrons , Peptídeos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/terapia , Linhagem Celular Tumoral
4.
Artigo em Inglês | MEDLINE | ID: mdl-37914976

RESUMO

PURPOSE: Prostate-specific membrane antigen (PSMA) is a promising diagnostic biomarker for prostate cancer (PCa). NYM016, a novel small-molecule PSMA-targeted fluorescence probe for the surgical navigation of PCa, was designed in this work. Furthermore, the potential of the PET agent [68Ga]Ga-NYM016 for the radionuclide imaging of PCa was evaluated. METHODS: NYM016 was designed with the near-infrared fluorescent group Cyanine 7 (Cy7) and the chelating group NOTA. The radioactive probe [68Ga]Ga-NYM016 was designed and synthesized on the basis of NYM016. The abovementioned probes were assessed in PSMA-positive xenograft-bearing models and patients diagnosed with PCa. RESULTS: NYM016 obviously aggregated in the tumor site of the mouse model, and its fluorescence intensity was stable within 24 h. NYM016 was well-tolerated, and no adverse events were found in the clinical study. Moreover, it was also observed in the excised lesions from the patient with PCa, and its fluorescence aggregated at the same site where PSMA was highly expressed. In addition, the PSMA xenograft demonstrated intense [68Ga]Ga-NYM016 uptake at 2.5 min after injection. At 3 h after injection, [68Ga]Ga-NYM016 uptake by the PSMA xenograft gradually increased to 6.40 ± 0.19%ID/g, which was higher that by the blocked and negative groups (2.28 ± 0.07%ID/g, P < 0.05; 2.28 ± 0.22%ID/g, P < 0.05). In the clinical study, [68Ga]Ga-NYM016 was well-tolerated and no adverse events were observed. Substantial accumulation was observed in primary and metastatic lesions in a patient with recurrence with the maximum standardized uptake value of 18.93. Meanwhile, negative [68Ga]Ga-NYM016 uptake was observed at the prostate site of a patient with prostatitis. CONCLUSION: The novel fluorescence probe NYM016 and the radioactive tracer [68Ga]Ga-NYM016 are promising candidates for the surgical navigation and radionuclide imaging of PCa, respectively. TRIAL REGISTRATION: The clinical evaluation of this study was registered at Clinicaltrial.gov (NCT05623878) on 21 Dec, 2022.

5.
Mol Pharm ; 20(8): 4277-4284, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37463487

RESUMO

Integrin α6 has been considered a promising biomarker, is overexpressed in many tumors, and plays a vital role in tumor formation, recurrence, and metastasis. In this study, we identified a novel high-affinity integrin α6-targeted peptide named RD2 (Arg-Trp-Tyr-Asp-PEG4)2-Lys-Lys and developed a 18F-radiolabeled peptide tracer ([18F]-AlF-NOTA-RD2) and evaluated its potential application in positron emission tomography (PET) imaging of pancreatic cancer. [18F]-AlF-NOTA-RD2 was produced using GMP (Good Manufacturing Practice of Medical Products)-compliant automatic radiosynthesis on a single GE FASTLab2 cassette-type synthesis module. The stability of [18F]-AlF-NOTA-RD2 was analyzed in phosphate-buffered saline (PBS) and fetal bovine serum (FBS). The cell uptake assay of the tracer was assessed using PANC-1 cells. In addition, small-animal PET imaging and biodistribution studies of [18F]-AlF-NOTA-RD2 were performed in pancreatic cancer subcutaneous tumor-bearing mice. The PET tracer [18F]-AlF-NOTA-RD2 was obtained with a radiochemical yield of 23.7 ± 4.7%, radiochemical purity of >99%, and molar activity of 165.7 ± 59.1 GBq/µmol. [18F]-AlF-NOTA-RD2 exhibited good in vitro stability in PBS and FBS. LogP octanol water value for the tracer was -2.28 ± 0.05 (n = 3). The binding affinity of RD2 to the integrin α6 protein (Kd = 0.13 ± 3.65 µM, n = 3) was significantly higher than that of the RWY (CRWYDENAC) (Kd = 6.97 ± 1.44 µM, n = 3). Small-animal PET imaging and biodistribution also revealed that [18F]-AlF-NOTA-RD2 displayed rapid and good tumor uptake and lower liver background uptake in PANC-1 tumor-bearing mice. [18F]-AlF-NOTA-RD2 showed significant radioactivity accumulation in tumors and was successfully blocked by NOTA-RD2. Compared with [18F]-FDG, [18F]-AlF-NOTA-RD2 PET imaging and biodistribution studies in PANC-1 xenograft tumor-bearing mice confirmed a good tumor-to-muscle ratio (8.69 ± 2.03 vs 1.41 ± 0.23, respectively) at 0.5 h and (2.99 ± 3.02 vs 1.43 ± 0.17, respectively) at 1 h post injection. Autoradiography of human pancreatic cancer tumor tissues further confirmed high accumulation of [18F]-AlF-NOTA-RD2. In summary, we developed an optimized integrin α6-targeted imaging tracer and obtained high radioactivity products with a cassette-type synthesis module; moreover, the tracer exhibited good binding affinity with integrin α6 and good target specificity for PANC-1 cells in xenograft pancreatic tumor-bearing mice, demonstrating its promising application as a noninvasive PET radiotracer of integrin α6 expression in pancreatic cancer.


Assuntos
Compostos Heterocíclicos com 1 Anel , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Integrina alfa6 , Distribuição Tecidual , Radioisótopos de Flúor , Linhagem Celular Tumoral , Tomografia por Emissão de Pósitrons/métodos , Peptídeos , Fluordesoxiglucose F18 , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas
6.
Eur J Oral Sci ; 131(3): e12928, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36931874

RESUMO

In this study, the synergistic effect of glutaraldehyde-cross-linking and remineralization on the strength and durability of resin-dentin bonds was investigated. Dentin surfaces were etched with 35% phosphoric acid. The control specimens were bonded with Adper Single Bond 2 using wet bonding without pretreatment. The experimental specimens were pretreated with 5% (v/v) glutaraldehyde solution for 3 min and placed in a remineralizing solution for 0, 12, and 24 h, followed by dry bonding. After performing composite build-ups on the specimens, they were longitudinally sectioned, immediately, and after aging for 3 h with sodium hypochlorite (NaOCl), to evaluate microtensile bond strength (µTBS). The cross-linked specimens exhibited µTBS values comparable with those of the control group, but the µTBS decreased significantly after NaOCl aging. The cross-linked dentin remineralized for 24 h exhibited an increase in µTBS. After aging in NaOCl, the µTBS of the specimens remineralized for 24 h did not decrease and was significantly higher than for the other experimental groups. Cross-linking with dry bonding maintained µTBS in specimens before aging in NaOCl, but the bonding durability was compromised. Remineralization of cross-linked dentin for 24 h followed by dry bonding increased the immediate µTBS and improved bond durability. Therefore, combining cross-linking with remineralization of collagen fibrils progressively increased resistance to degradation, improving bond durability.


Assuntos
Colagem Dentária , Adesivos Dentinários , Adesivos Dentinários/química , Glutaral/farmacologia , Cimentos de Resina/química , Teste de Materiais , Colágeno , Dentina , Resistência à Tração
7.
Lipids Health Dis ; 22(1): 38, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36906544

RESUMO

BACKGROUND: There is limited longitudinal evidence supporting the association between the hypertriglyceridemic-waist (HTGW) phenotype and hyperuricemia. This study aimed to examine the longitudinal relationship between hyperuricemia and the HTGW phenotype among males and females. METHODS: A total of 5562 hyperuricemia-free participants aged 45 or over from the China Health and Retirement Longitudinal Study (mean age: 59.0) were followed for 4 years. The HTGW phenotype was defined as having elevated triglyceride levels and enlarged waist circumference (cutoffs for males: 2.0 mmol/L and 90 cm; females: 1.5 mmol/L and 85 cm). Hyperuricemia was determined by uric acid cutoffs (males: 7 mg/dl; females: 6 mg/dl. Multivariate logistic regression models were used to assess the association between the HTGW phenotype and hyperuricemia. The joint effect of the HTGW phenotype and sex on hyperuricemia was quantified, and the multiplicative interaction was assessed. RESULTS: During the four-year follow-up, 549 (9.9%) incident hyperuricemia cases were ascertained. Compared with those with normal levels of triglycerides and waist circumference, participants with the HTGW phenotype had the highest risk of hyperuricemia (OR: 2.67; 95% CI: 1.95 to 3.66), followed by an OR of 1.96 (95% CI: 1.40 to 2.74) for only higher triglyceride levels and 1.39 (95% CI: 1.03 to 1.86) for only greater waist circumference. The association between HTGW and hyperuricemia was more prominent among females (OR = 2.36; 95% CI: 1.77 to 3.15) than males (OR = 1.29; 95% CI: 0.82 to 2.04), with evidence of a multiplicative interaction (P = 0.006). CONCLUSIONS: Middle-aged and older females with the HTGW phenotype may at the highest risk of hyperuricemia. Future hyperuricemia prevention interventions should be primarily targeted for females with the HTGW phenotype.


Assuntos
Cintura Hipertrigliceridêmica , Masculino , Feminino , Humanos , Estudos Longitudinais , Cintura Hipertrigliceridêmica/complicações , Fenótipo , Triglicerídeos , Modelos Logísticos , Fatores de Risco , Circunferência da Cintura
8.
Chem Soc Rev ; 51(19): 8378-8405, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36112107

RESUMO

Developing hierarchical ordered systems is challenging. Using organo-macrocycles to construct metal-organic frameworks (MOFs) and porous coordination cages (PCCs) provides an efficient way to obtain hierarchical assemblies. Macrocycles, such as crown ethers, cyclodextrins, calixarenes, cucurbiturils, and pillararenes, can be incorporated within MOFs/PCCs and they also endow the resultant composites with enhanced properties and functionalities. This review summarizes recent developments of organo-macrocycle-containing hierarchical MOFs/PCCs, emphasizing applications and structure-property relationships of these hierarchically porous materials. This review provides insights for future research on hierarchical self-assembly using macrocycles as building blocks and functional ligands to extend the applications of the composites.


Assuntos
Calixarenos , Éteres de Coroa , Ciclodextrinas , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Porosidade
9.
BMC Cancer ; 22(1): 216, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35227236

RESUMO

OBJECTIVE: Neuroblastoma is a common extracranial solid tumor of childhood. Recently, multiple treatments have been practiced including Iodine-131-metaiodobenzylguanidine radiation (131I-MIBG) therapy. However, the outcomes of efficacy and safety vary greatly among different studies. The aim of this meta-analysis is to evaluate the efficacy and safety of 131I-MIBG in the treatment of neuroblastoma and to provide evidence and hints for clinical decision-making. METHODS: Medline, EMBASE database and the Cochrane Library were searched for relevant studies. Eligible studies utilizing 131I-MIBG in the treatment of neuroblastoma were included. The pooled outcomes (response rates, adverse events rates, survival rates) were calculated using either a random-effects model or a fixed-effects model considering of the heterogeneity. RESULTS: A total of 26 clinical trials including 883 patients were analyzed. The pooled rates of objective response, stable disease, progressive disease, and minor response of 131I-MIBG monotherapy were 39%, 31%, 22% and 15%, respectively. The pooled objective response rate of 131I-MIBG in combination with other therapies was 28%. The pooled 1-year survival and 5-year survival rates were 64% and 32%. The pooled occurrence rates of thrombocytopenia and neutropenia in MIBG monotherapy studies were 53% and 58%. In the studies of 131I-MIBG combined with other therapies, the pooled occurrence rates of thrombocytopenia and neutropenia were 79% and 78%. CONCLUSION: 131I-MIBG treatment alone or in combination of other therapies is effective on clinical outcomes in the treatment of neuroblastoma, individualized 131I-MIBG is recommended on a clinical basis.


Assuntos
3-Iodobenzilguanidina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Neuroblastoma/tratamento farmacológico , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Tumores Neuroendócrinos/tratamento farmacológico , Neutropenia/induzido quimicamente , Taxa de Sobrevida , Resultado do Tratamento
10.
Inorg Chem ; 61(8): 3412-3419, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35171582

RESUMO

In this work, novel metal-organic framework/polyimide (MOF/PI) composite films possessing dielectric properties were synthesized via a solution blending method. UiO-66 and UiO-66-NH2 nanoparticles were first prepared by a hydrothermal method and added into PI to obtain the composite films. Compared with pure PI, the dielectric properties of the MOF/PI composites were substantially enhanced. The amine functionalization gave UiO-66-NH2/PI composite films better dielectric properties in comparison with UiO-66/PI composite films because of improved interaction between PI and UiO-66-NH2. It showed that the dielectric constant of the PI composite film containing 20 wt% UiO-66-NH2 is 8.8 at 102 Hz, which was approximately 2.5 times that of the pure PI (3.5 at 102 Hz). The dielectric loss of the composite film was less than 0.034. Moreover, the breakdown strength of 20 wt% UiO-66-NH2/PI composite films was found to be 208 kV/mm. We describe this new perspective for the preparation of high-performance polymer-based dielectric materials and their application as electrical materials.

11.
Aging Clin Exp Res ; 34(8): 1893-1900, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35524107

RESUMO

BACKGROUND: Healthy aging index (HAI) could predict adverse health consequences including mortality and disability independent of age and comorbidity. We investigated the role of HAI on trajectories of disability throughout later life based on a nationally representative sample. METHODS: We examined 1733 participants aged over 60 years from the China Health and Retirement Longitudinal Study (CHARLS) followed for 7 years/4 waves repeatedly. Systolic blood pressure [SBP], cognitive function, cystatin C, peak expiratory flow [PEF], and fasting glucose were categorized using tertile or clinical reference range, and scored as 0 (healthiest), 1 (less healthy) and 2 (least healthy) respectively to further generate HAI summary scores (range 0-10). Disability was defined as the sum of impaired activities of daily living (ADL) and instrumental activities of daily living (IADL). We used linear mixed-effects model to study the association between HAI and trajectories of disability. RESULTS: A total of 10.5% of participants represented in the healthiest group and 22.5% ended up as the least healthy. After adjusting for all potential confounders, disability progression was significantly faster (ß = 0.27, 95% CI 0.11-0.42) in the least healthy group when comparing with the healthiest. CONCLUSION: Our findings suggest that HAI is associated with disability progression among adults aged over 60 years old. It might be beneficial for future interventions to specifically target older adults with high HAI scores as a means of reducing disability.


Assuntos
Pessoas com Deficiência , Envelhecimento Saudável , Atividades Cotidianas , Idoso , China/epidemiologia , Estudos de Coortes , Avaliação da Deficiência , Humanos , Estudos Longitudinais
12.
Ecotoxicol Environ Saf ; 228: 112918, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34773846

RESUMO

Ambient particulate matter <2.5 µm (PM2.5) has been identified as a critical risk factor in chronic obstructive pulmonary disease (COPD) exacerbation, but therapies for this condition are limited. Effective-component compatibility of Bufei Yishen formula (ECC-BYF) exhibits beneficial efficacy on COPD rats. However, its effect on PM2.5-aggravated COPD rats are considered to be uncertain. In this study, we used an established PM2.5-aggravated COPD rat model in vivo to evaluate the protective effect of ECC-BYF, and focused on its antioxidative role in PM2.5-stimulated bronchial epithelial cells via regulating microRNA (miR)-155/ forkhead box class O3a (FOXO3a) pathway. As expected, PM2.5-aggravated COPD rats showed a reduction of lung function, persistent lung inflammation, and remodeling of lung tissue. In comparison, ECC-BYF administration significantly enhanced lung function, alleviated alveolar destruction, inflammatory cell infiltration, mucus hypersecretion, and collagen deposition, along with diminishing inflammatory cytokine production and oxidative stress. Furthermore, ECC-BYF pretreatment markedly decreased the fluorescence intensity of reactive oxygen species (ROS) in PM2.5-induced human bronchial epithelial (Beas-2B) cells and primary mouse tracheal epithelial cells (MTECs), as well as reversing the imbalance between oxidants and antioxidants in Beas-2B. Meanwhile, ECC-BYF elevated FOXO3a while inhibiting miR-155 expression dose -dependently. In vitro transfection of miR-155 mimic into Beas-2B significantly decreased FOXO3a protein expression, accompanied by the reduced superoxide dismutase 2 (SOD2) and catalase (CAT) expressions, thus eliminating the protective effect of ECC-BYF on PM2.5-evoked oxidative stress. Nonethless, FOXO3a overexpression could partially restore the antioxidative effect of ECC-BYF. In conclusion, ECC-BYF can protect pre-existing COPD against PM2.5 contamination by exerting a profound antioxidative influence via regulating miR-155/FOXO3a signaling.

13.
Inorg Chem ; 59(1): 695-704, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31815448

RESUMO

Following the principle of a topology guide, a zirconium MOF (PCN-207) based on the H4TPTA ligand (tetramethyl(4,4',4″,4‴-(pyrazine-2,3,5,6-tetrayl))tetrabenzoic acid) with C2 symmetry and an 8-connected Zr6(µ3-OH)8(OH)8]8+ cluster with D4h symmetry has been synthesized. PCN-206 can also be obtained by modulating the benzoic acid usage to change the flexibility of the H4TPTA ligand. The unique positions of 8-connected Zr6 clusters in the flu and scu networks and the flexibility of the tetratopic primary linker enable the precise insertion of fumarate (FA), 1,4-benzenedicarboxylic acid (H2BDC), and even 2,6-naphthalenedicarboxylic acid (H2NDC) in a one-pot reaction. Auxiliary linkers are used to generate new MOF structures or topologies or to split the pore spaces, which may significantly change the porosity and chemical and physical properties of scaffold MOFs. The results provide a successful strategy for the rational design of multicomponent Zr-MOFs. Because of differences in composition and configuration between structures, PCN-207 shows the highest separation capability of light hydrocarbons; moreover, PCN-206 exhibits the highest adsorption capacity of 2,4-D and DCF among MOFs at present.

14.
Mediators Inflamm ; 2020: 4260204, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32454790

RESUMO

Particulate matter with an aerodynamic diameter equal or less than 2.5 micrometers (PM2.5) is associated with the development of chronic obstructive pulmonary disease (COPD). The mechanisms by which PM2.5 accelerates disease progression in COPD are poorly understood. In this study, we aimed to investigate the effect of PM2.5 on lung injury in rats with hallmark features of COPD. Cardinal features of human COPD were induced in a rat model by repeated cigarette smoke inhalation and bacterial infection for 8 weeks. Then, from week 9 to week 16, some of these rats with COPD were subjected to real-time concentrated atmospheric PM2.5. Lung function, pathology, inflammatory cytokines, oxidative stress, and mucus and collagen production were measured. As expected, the COPD rats had developed emphysema, inflammation, and deterioration in lung function. PM2.5 exposure resulted in greater lung function decline and histopathological changes, as reflected by increased Mucin (MUC) 5ac, MUC5b, Collagen I, Collagen III, and the profibrotic cytokine α-smooth muscle-actin (SMA), transforming growth factor- (TGF-) ß1 in lung tissues. PM2.5 also aggravated inflammation, increasing neutrophils and eosinophils in bronchoalveolar lavage fluid (BALF) and cytokines including Interleukin- (IL-) 1ß, granulocyte-macrophage colony-stimulating factor (GM-CSF), and IL-4. The likely mechanism is through oxidative stress as antioxidants levels were decreased, whereas oxidants were increased, indicating a detrimental shift in the oxidant-antioxidant balance. Altogether, these results suggest that PM2.5 exposure could promote the development of COPD by impairing lung function and exacerbating pulmonary injury, and the potential mechanisms are related to inflammatory response and oxidative stress.


Assuntos
Poluição do Ar/efeitos adversos , Estresse Oxidativo , Tamanho da Partícula , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Animais , Líquido da Lavagem Broncoalveolar , Colágeno/química , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Inflamação , Pulmão/patologia , Masculino , Material Particulado , Ratos , Ratos Sprague-Dawley , Fatores de Risco , Fumaça
15.
Sensors (Basel) ; 19(19)2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31561420

RESUMO

A commercially available microtiter plate reader was applied as a high-throughput counterpart of ultraviolet-visible (UV-Vis) spectrophotometer to identify the producing location of extra virgin olive oils (EVOOs). Multiplicative scatter correction and the first derivative was used to denoise the UV-Vis spectra and eliminate the effects of background drift. The spectra were analyzed using chemometrics methods including the principal component analysis (PCA) and the partial least squares-discriminant analysis (PLS-DA). The PLS-DA model on full spectra using 5 latent variables showed a classification accuracy of 97.92% by cross-validation. The overall results demonstrated that the use of a UV-Vis spectrophotometer based on the microtiter plate reader combined with chemometrics can be applied to the quality assessment of EVOOs. It is demonstrated that the microtiter plate reader can be a high-throughput tool in the quality assessment of food ingredients.

16.
Entropy (Basel) ; 21(4)2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33267114

RESUMO

In recent years, a new method of fault diagnosis, named variational mode decomposition (VMD), has been widely used in industrial production, but the decomposition accuracy of VMD is determined by two parameters, which are respectively the decomposition layer number k and the penalty factor α, if the parameters are not properly selected, there will be over-decomposition or under-decomposition. In order to find an approach to determine the parameters adaptively, a method to optimize VMD by using the immune fruit fly optimization algorithm (IFOA) is proposed in this paper. In this method, permutation entropy is used as the fitness function, firstly, the immune fruit fly optimization algorithm is used to search the combined parameters of k and α in VMD, searching for the best combination parameters of k and α by iteration, and then uses the combined parameters to perform VMD, finally, the center frequency is determined through frequency spectrum analysis. The method mentioned is applied to the fault extraction of a simulated signal and a measured signal of a wind turbine gearbox, and the fault frequency is successfully extracted. Using ensemble empirical mode decomposition (EEMD) and singular spectrum decomposition (SSD) to compare with the proposed method, which validated feasibility of the proposed method.

17.
Sensors (Basel) ; 19(1)2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30586921

RESUMO

Under the strong noise environment, the composite fault signal of gearbox is weak, which makes it difficult to extract fault features. For this problem, based on noise-assisted method, we propose a novel method called Modified Singular Spectrum Decomposition (MSSD). Singular Spectrum Decomposition (SSD) has many advantages such as high decomposition precision and strong ability to restrain mode mixing, etc. However, the ability of SSD to extract a weak signal is not ideal, the decomposition results usually contain a lot of redundant noise and mode mixing caused by intermittency, which is also a troubling problem. In order to improve the decomposition efficiency and make up for the defects of SSD, the new method MSSD adds an adaptive and particular noise in every SSD decomposition stage for each trial, and in addition, whenever the input signal is decomposed to obtain an intrinsic module function (IMF), a unique residual is obtained. After multiple decomposition, the average value of the residual is used as input to the next stage, until the residual cannot continue to decompose, which means that the residual component has, at most, one extreme value. Finally, analyzing simulated signals to explain the advantages of MSSD compared to ensemble empirical mode decomposition (EEMD) and complete ensemble local mean decomposition with adaptive noise (CEEMDAN). In order to further prove the effectiveness of MSSD, this new method, MSSD, is applied to the fault diagnosis of an engineering gearbox test stand in an actual engineer project case. The final results show that MSSD can extract more fault feature information, and mode mixing has been improved and suffers less interference compared to SSD.

18.
ISA Trans ; 150: 311-321, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38729908

RESUMO

Unsupervised domain adaptation has been extensively researched in rotating-machinery cross-domain fault diagnosis. A multi-source domain adaptive network based on local kernelized higher-order moment matching is constructed in this research for rotating-machinery fault diagnosis. Firstly, a multi-branch network is designed to map each source-target pair to a domain-specific shared space and to extract domain-invariant features using domain adversarial thought. Then, a local kernelized higher-order moment matching algorithm is proposed to perform fine-grained matching in shared category subspace. Finally, a feature fusion strategy based on the local domain distribution deviation is applied to synthesize the output features of multiple classifiers to obtain diagnostic results. The experimental validation of two-branch and three-branch networks on two public datasets is carried out and average diagnostic accuracies both exceed 99%. The results demonstrate the effectiveness and superiority of the approach.

19.
J Affect Disord ; 359: 196-205, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38777265

RESUMO

BACKGROUND: This study examines the extent to which depressive symptoms mediate the link between childhood friendship (CF) and physical function among middle-aged and older adults in China. METHODS: China Health and Retirement Longitudinal Study (CHARLS) data were used; specifically, CHARLS life history survey (conducted from June 1-December 31, 2014) and follow-up health survey (conducted from July 1-September 30, 2015) data were used. The Sobel test, Bootstrap test and multivariable logistic regression were performed to examine the mediating role of depressive symptoms (measured by the 10-item Center for Epidemiologic Studies Depression Scale) in the association between CF (measured by a standardized retrospective questionnaire) and physical function, which was measured by basic activities of daily living (BADL) disability, instrumental activities of daily living (IADL) disability, and grip strength. RESULTS: A total of 12,170 participants aged 45 years or older were included in this cross-sectional study. After controlling for covariates, low-quality CF was associated with an increased prevalence of BADL disability (OR = 1.18; 95 % CI = 1.05-1.32), IADL disability (OR = 1.25; 95 % CI = 1.12-1.40), and low grip strength (OR = 1.21; 95 % CI = 1.09-1.34). The proportion of the mediating effect of depressive symptoms was 48 % for CF and BADL, 40 % for CF and IADL, and 11 % for CF and grip strength. Depressive symptoms and worse CF have a joint effect on BADL disability (OR = 3.30; 95 % CI = 2.82-3.85), IADL disability (OR = 3.52; 95 % CI = 3.03-4.09), and low grip strength (OR = 1.65; 95 % CI = 1.43-1.92). LIMITATIONS: Not all potential confounding factors (such as childhood behavioural problems, genetic factors, and memory function) were measured in the analysis, and there may have been recall bias in the retrospective collection of CF data. CONCLUSIONS: Individuals with high-quality CF were more likely to have a decreased prevalence of impaired physical function in later life. Depressive symptoms acted as a mediator associated with the development of CF.


Assuntos
Atividades Cotidianas , Depressão , Amigos , Humanos , Masculino , Feminino , China/epidemiologia , Estudos Longitudinais , Depressão/epidemiologia , Idoso , Pessoa de Meia-Idade , Estudos Transversais , Amigos/psicologia , Aposentadoria/estatística & dados numéricos , Aposentadoria/psicologia , Força da Mão , Prevalência
20.
Nanoscale ; 16(3): 1406-1414, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38165953

RESUMO

Itinerant ferromagnetism at room temperature is a key factor for spin transport and manipulation. Here, we report the realization of near-room temperature itinerant ferromagnetism in Co doped Fe5GeTe2 thin flakes. The ferromagnetic transition temperature TC (∼323 K-337 K) is almost unchanged when the thickness is as low as 12 nm and is still about 284 K at 2 nm (bilayer thickness). Theoretical calculations further indicate that the ferromagnetism persists in monolayer Fe4CoGeTe2. In addition to the robust ferromagnetism down to the ultrathin limit, Fe4CoGeTe2 exhibits an unusual temperature- and thickness-dependent intrinsic anomalous Hall effect. We propose that it could be ascribed to the dependence of the band structure on thickness that changes the Berry curvature near the Fermi energy level subtly. The near-room temperature ferromagnetism and tunable anomalous Hall effect in atomically thin Fe4CoGeTe2 provide opportunities to understand the exotic transport properties of two-dimensional van der Waals magnetic materials and explore their potential applications in spintronics.

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