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1.
Sci Total Environ ; 954: 176415, 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39312972

RESUMEN

Inhaled dose is crucial for accurately assessing exposure to air pollution, determined by pollutant concentration and minute ventilation (VE). However, the VE predictive models and its application to assess the health effects of air pollution are still lacking. In this study, we developed VE predictive models using machine learning techniques, utilizing data obtained from eighty participants who underwent a laboratory cardiopulmonary exercise test (CPET). VE predictive models were developed using generalized additive model (GAM), random forest model (RF) and extreme gradient boosting (XGBoost) and analyzed for explanation of input variables. The Random Forest model, cross-validated, exhibited outstanding performance with an R2 of 0.986 and a MAE of 1.816 L/min. The median difference between the measured VE and the predicted VE was 0.18 L/min, and the median difference between the black carbon (BC) inhaled dose based on predicted VE and measured VE was 0.02 ng. Employing explainable machine learning, the results showed that metabolic equivalent (METs), heart rate, and body weight are the three top important variables, emphasizing the significance of incorporating METs variables when constructing VE models. Through multiple linear regression models and an adjusted stratified analysis model, the significant adverse association between BC concentration and inhaled dose on diastolic blood pressure (DBP) was only observed in female. The disparity in the effect of BC inhaled dose compared to BC concentration on DBP reached up to 115 %. This study is the first to explore the ability of different machine learning algorithms to construct VE prediction models and directly apply the models to assess health effects of an example pollutant. This study contributes to the accurate assessment of air pollution exposure leveraging wearable devices, an approach useful for environmental epidemiology studies.

2.
ACS Nano ; 18(34): 23537-23552, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39133543

RESUMEN

Numerous small biomolecules exist in the human body and play roles in various biological and pathological processes. Small molecules are believed not to induce intrafibrillar mineralization alone. They are required to work in synergy with noncollagenous proteins (NCPs) and their analogs, e.g. polyelectrolytes, for inducing intrafibrillar mineralization, as the polymer-induced liquid-like precursor (PILP) process has been well-documented. In this study, we demonstrate that small charged molecules alone, such as sodium tripolyphosphate, sodium citrate, and (3-aminopropyl) triethoxysilane, could directly mediate fibrillar mineralization. We propose that small charged molecules might be immobilized in collagen fibrils to form the polyelectrolyte-like collagen complex (PLCC) via hydrogen bonds. The PLCC could attract CaP precursors along with calcium and phosphate ions for inducing mineralization without any polyelectrolyte additives. The small charged molecule-mediated mineralization process was evidenced by Cryo-TEM, AFM, SEM, FTIR, ICP-OES, etc., as the PLCC exhibited both characteristic features of collagen fibrils and polyelectrolyte with increased charges, hydrophilicity, and density. This might hint at one mechanism of pathological biomineralization, especially for understanding the ectopic calcification process.


Asunto(s)
Citrato de Sodio , Citrato de Sodio/química , Citrato de Sodio/metabolismo , Animales , Humanos , Citratos/química , Colágeno/química , Colágeno/metabolismo , Calcinosis/metabolismo , Calcinosis/patología , Propilaminas/química
3.
Nat Commun ; 15(1): 6688, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107273

RESUMEN

Human society is facing increasingly serious problems of environmental pollution and energy shortage, and up to now, achieving high NH3-SCR activity at ultra-low temperatures (<150 °C) remains challenging for the V-based catalysts with V content below 2%. In this study, the monoatomic V-based catalyst under the weak current-assisted strategy can completely convert NOx into N2 at ultra-low temperature with V content of 1.36%, which shows the preeminent turnover frequencies (TOF145 °C = 1.97×10-3 s-1). The improvement of catalytic performance is mainly attributed to the enhancement catalysis of weak current (ECWC) rather than electric field, which significantly reduce the energy consumption of the catalytic system by more than 90%. The further mechanism research for the ECWC based on a series of weak current-assisted characterization means and DFT calculations confirms that migrated electrons mainly concentrate around the V single atoms and increase the proportion of antibonding orbitals, which make the V-O chemical bond weaker (electron scissors effect) and thus accelerate oxygen circulation. The novel current-assisted catalysis in the present work can potentially apply to other environmental and energy fields.

4.
BMC Oral Health ; 24(1): 541, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38720320

RESUMEN

BACKGROUND: Widespread exposure to phthalates may raise the probability of various diseases. However, the association of phthalate metabolites with periodontitis remains unclear. METHODS: Totally 3402 participants from the National Health and Nutrition Examination Survey (NHANES) 2009 to 2014 cycles were enrolled in the cross-sectional investigation. We utilized weighted logistic regression to evaluate the association of ten phthalate metabolites with periodontitis. Restricted cubic spline analysis was applied to investigate potential nonlinear relationships. RESULTS: The weighted prevalence of periodontitis in the study was 42.37%. A one standard deviation (SD) rise in log-transformed levels of mono-2-ethyl-5-carboxypenty phthalate (MECPP), mono-n-butyl phthalate (MnBP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-isobutyl phthalate (MiBP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono-benzyl phthalate (MBzP) was associated with higher odds of periodontitis, with odds ratios (95% confidence intervals) of 1.08 (1.02-1.14), 1.07 (1.02-1.11), 1.10 (1.05-1.15), 1.05 (1.01-1.09), 1.09 (1.04-1.14), and 1.08 (1.03-1.13), respectively. Individuals with the highest quartile concentrations of MECPP, MnBP, MEHHP, MEOHP, and MBzP were associated with 32%, 20%, 30%, 25%, and 26% increased odds of periodontitis, respectively, compared to those with the lowest quartile. Additionally, mono-(3-carboxypropyl) phthalate (MCPP) demonstrated an interesting inverted J-shaped relationship with periodontitis. CONCLUSIONS: The findings indicate an association of certain phthalate metabolites with periodontitis among US adults.


Asunto(s)
Encuestas Nutricionales , Periodontitis , Ácidos Ftálicos , Humanos , Ácidos Ftálicos/metabolismo , Femenino , Estudios Transversales , Masculino , Adulto , Periodontitis/epidemiología , Periodontitis/metabolismo , Persona de Mediana Edad , Estados Unidos/epidemiología , Prevalencia , Adulto Joven
5.
Eco Environ Health ; 3(2): 202-207, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38655004

RESUMEN

Air pollution is a major contributor to the global disease burden, especially affecting respiratory and cardiovascular health. However, physical activity is associated with improved lung function, a slower decline in lung function, and lower mortality. The public is more likely to be exposed to air pollution during outdoor physical activity. However, studies on how long-term and short-term exposure to air pollution interacts with physical activity yield inconsistent results, and the thresholds for air pollution and physical activity remain unclear. Thus, more studies are needed to provide sufficient evidence to guide the public to safely engage in outdoor physical activity when exposed to air pollution.

6.
Int J Biol Macromol ; 258(Pt 1): 128803, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38104685

RESUMEN

Insoluble dietary fiber (IDF) has been characterized to prevent chronic diseases and improve gastrointestinal health, and it has been added to 3D printing plant-based meats (PM) to enhance texture and increase nutritional properties. Therefore, the aim of this study was to investigate the effects of IDF on 3D printing properties and molecular interactions of soy protein isolate (SPI) - wheat gluten (WG) PM. Without the participation of IDF, PM appeared to collapse. When the IDF concentration increased from 0 to 10 %, PM displayed good printing properties, water holding capacity, tensile strength, and elongation at break were increased. Tensile strength and elongation at break reached a maximum at 10 % IDF, and clearly similar results were found for texture attribute indices such as hardness, gumminess, chewiness, and cohesiveness after cooking. All printing inks exhibited shear-thinning behavior and solid-like viscoelasticity, but the structural recovery properties of 3D-printed PM deteriorated when the IDF content was over 10 %. Intermolecular forces indicated that the addition of IDF enhanced the disulfide bonds so that 10 % IDF presented better printing properties. These results indicated the potential for developing PM with dietary fiber functionality through 3D printing technology.


Asunto(s)
Proteínas de Soja , Triticum , Proteínas de Soja/química , Triticum/química , Glútenes/química , Fibras de la Dieta , Carne
7.
J Hazard Mater ; 459: 132209, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37567137

RESUMEN

It is essential to develop the catalyst for NH3-SCR with excellent performance at ultra-low temperature (≤150 °C), and resource recycling is another important part of environmental protection. Based on the principle of environmental friendliness, the LiMn2O4, one of the waste battery cathode materials, was successfully modified into a novel high-value catalyst for ultra-low temperature NH3-SCR through hydrogen ion exchange and two-dimensional vanadic oxide modification. The optimized LiMn2O4-0.5V-10H catalyst performed the best balance of NOx conversion and N2 selectivity, with activity reaching 96 % at 150 °C and N2 selectivity exceeding 70 % at ultra-low temperature. Due to the unique three-dimensional network structural characteristics of LiMn2O4 spinel, hydrogen exchange could exchange Li+ from the lattice and increase surface acidity; and a small amount of two-dimensional vanadic oxide loading could appropriately regulate redox ability and increase acidic sites. The in-situ DRIFTS results still showed that the L-H and E-R mechanisms coexisted during the reaction. Moreover, combining first-principles calculations and in-situ DRIFTS, the dual modification of H and V could enhance the adsorption of NH3 on the surface of LiMn2O4 but weaken the adsorption of NO, and promote the decomposition of nitrites while inhibit the formation of surface nitrate species, which was the core reason for the improvement of N2 selectivity. The modification mode in this work was simple and inexpensive, which provided a new idea for the high-value utilization of waste batteries and the design of NOx purification catalyst at ultra-low temperature.

8.
Int J Nanomedicine ; 18: 3727-3744, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37441084

RESUMEN

Background: In chronic periodontitis, exosomes transport various informative substances between osteoclasts and osteoblasts in alveolar bone. Herein, we aimed to investigate the effect of exosomal micro-ribonucleic acid (miRNA/miR)-5134-5p derived from osteoclasts on osteoblastic proliferation and differentiation and the development of periodontitis in vivo and in vitro. Methods: The effects of OC-Exos on the proliferation and differentiation of osteoblasts were identified by Real-time quantitative reverse polymerase chain reaction (qRT-PCR), Western blot(WB), alkaline phosphatase(ALP) staining, etc. Exosomal miRNA expression was analyzed by sequencing. The sites of miRNA action were predicted through TargetScan and tested by double luciferase assay. After transfecting miR-5134-5p mimic/inhibitor into osteoblasts, we measured the proliferation and differentiation of osteoblasts by ALP staining and WB, etc. Furthermore, OC-Exos were injected into the gingival sulcus at the ligation site. Inflammation was observed by Hematoxylin-eosin (H&E) staining, the expression of inflammatory factors were detected by qRT-PCR, the resorption of alveolar bone was observed by Micro CT. Results: Osteoblastic proliferation and differentiation were negatively regulated by OC-Exos in vitro. miRNA sequencing analysis revealed that miR-5134-5p expression was significantly elevated in OC-Exos, which also increased in osteoblasts following OC-Exo intervention. The dual-luciferase assay revealed that miR-5134-5p and Janus kinase 2 (JAK2) had binding sites. miR-5134-5p-mimics could upregulate miR-5134-5p expression in osteoblasts while downregulating Runt-related transcription factor 2(Runx2), phosphorylated-JAK2 (p-JAK2), and phosphorylated-signal transducer and activator of transcription 3 (p-STAT3) expression and inhibited osteogenic differentiation. However, miR-5134-5p-inhibitor had the opposite effect. In vivo, the OC-Exo group demonstrated morphological disruption of periodontal tissue, massive inflammatory cell infiltration, upregulation of inflammatory factors mRNA expression, a significant decrease in BV/TV, and an increase in the cementoenamel junction and alveolar bone crest distance. Conclusion: Osteoclast-derived exosomal miR-5134-5p inhibits osteoblastic proliferation and differentiation via the JAK2/STAT3 pathway. OC-Exos exacerbate periodontal tissue inflammation and accelerate alveolar bone resorption in mice with experimental periodontitis.


Asunto(s)
MicroARNs , Periodontitis , Ratones , Animales , Osteogénesis/genética , Osteoclastos/metabolismo , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , MicroARNs/metabolismo , Diferenciación Celular , Osteoblastos , Periodontitis/genética , Inflamación/metabolismo , Homeostasis , Luciferasas/metabolismo
9.
ACS Biomater Sci Eng ; 9(4): 1961-1975, 2023 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-36942823

RESUMEN

Periodontal tissue regeneration is a major challenge in tissue engineering due to its regenerated environment complexity. It aims to regenerate not only the supporting alveolar bone and cementum around teeth but also the key connecting periodontal ligament. Herein, a constructed aligned porous hydrogel scaffold carrying cells based on chitosan (CHI) and oxidized chondroitin sulfate (OCS) treated with a freeze-casting technique was fabricated, which aimed to induce the arrangement of periodontal tissue regeneration. The microscopic morphology and physical and chemical properties of the hydrogel scaffold were evaluated. The biocompatibilities with periodontal ligament stem cells (PDLSCs) or gingival-derived mesenchymal stem cells (GMSCs) were verified, respectively, by Live/Dead staining and CCK8 in vitro. Furthermore, the regeneration effect of the aligned porous hydrogel scaffold combined with PDLSCs and GMSCs was evaluated in vivo. The biocompatibility experiments showed no statistical significance between the hydrogel culture group and blank control (P > 0.05). In a rat periodontal defect model, PDLSC and GMSC hydrogel experimental groups showed more pronounced bone tissue repair than the blank control (P < 0.05) in micro-CT. In addition, there was more tissue repair (P < 0.05) of PDLSC and GMSC hydrogel groups from histological staining images. Higher expressions of OPN, Runx-2, and COL-I were detected in both of the above groups via immunohistochemistry staining. More importantly, the group with the aligned porous hydrogel induced more order periodontal ligament formation than that with the ordinary hydrogel in Masson's trichrome analysis. Collectively, it is expected to promote periodontal tissue regeneration utilizing an aligned porous hydrogel scaffold combined with PDLSCs and GMSCs (CHI-OCS-PDLSC/GMSC composite), which provides an alternative possibility for clinical application.


Asunto(s)
Células Madre Mesenquimatosas , Ligamento Periodontal , Ratas , Animales , Ligamento Periodontal/metabolismo , Ligamento Periodontal/patología , Porosidad , Andamios del Tejido/química , Materiales Biocompatibles/farmacología , Células Madre , Células Madre Mesenquimatosas/metabolismo , Hidrogeles/farmacología , Hidrogeles/metabolismo
10.
Environ Sci Pollut Res Int ; 30(15): 43690-43701, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36658317

RESUMEN

The trade-off between the potentially detrimental effects of fine particulate matter (PM2.5) and the benefits of physical activity (PA) is unclear. We aimed to explore the independent and interaction effects between long-term PM2.5 exposure and PA on blood pressure (BP) and hypertension. A total of 8704 adults (≥45 years) without hypertension at baseline in a nationwide cohort of the China Health and Retirement Longitudinal Study (CHARLS) were followed from 2011 to 2015. The participants were selected using a four-stage, stratified, and cluster sampling procedure. The annual PM2.5 concentrations at the residential address were estimated from a two-stage machine learning model with a 10 km × 10 km resolution. A standard questionnaire collected information on PA and potential confounders, and metabolic equivalents (MET·h/wk), which combined frequency, intensity, and duration information, were used to assess PA levels. We adopted mixed-effects regression models to explore the independent and interaction effects between long-term PM2.5 exposure and PA on BP and risk of hypertension. Systolic blood pressure (SBP) decreased by -0.84 mmHg (95% CI: -1.34, -0.34) per an IQR (interquartile range, 175.5 MET·h/wk) increase in PA, and diastolic blood pressure (DBP) decreased by -0.42 mmHg (95% CI: -0.76, -0.07). Each IQR (36.1 µg/m3) increment in PM2.5 was associated with 0.48 mmHg (95% CI: -0.24, 1.20) in SBP and -0.02 mmHg (95% CI: -0.44, 0.39) in DBP. PM2.5 showed an elevated effect with risks of hypertension (odds ratio, OR = 1.01; 95% CI: 1.00, 1.03), while PA showed the inverse result (OR = 0.98; 95% CI: 0.97, 0.99). Interaction analyses indicated PA maintained the beneficial effects on BP, but the negative association was attenuated, accompanied by the increase of PM2.5. PA decreased the BP and hypertension risks, while PM2.5 showed the opposite results. PM2.5 attenuated the beneficial effects of PA on BP and modified the association between PA and the risk of hypertension.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Hipertensión , Adulto , Humanos , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Estudios Longitudinales , Contaminación del Aire/análisis , Exposición a Riesgos Ambientales/análisis , Presión Sanguínea , Ejercicio Físico , China
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