Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.022
Filtrar
1.
J Colloid Interface Sci ; 677(Pt A): 189-197, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38871628

RESUMO

The utilization of a cost-free sacrificial agent is a novel approach to significantly enhance the efficiency of photocatalytic hydrogen (H2) production by water splitting. Wastewater contains various organic pollutants, which have the potential to be used as hole sacrificial agents to promote H2 production. Our studies on different pollutants reveals that not all pollutants can effectively promote H2 production. However, when using the same pollutants, not all photocatalysts achieved a higher H2 evolution rate than pure water. Only when the primary oxidizing active species of the photocatalyst are •OH radicals, which are generated by photogenerated holes, and when the pollutants are easily attacked and degraded by •OH radicals, can the production of H2 be effectively promoted. It is noteworthy that the porous brookite TiO2 photocatalyst exhibits a significantly higher H2 evolution rate in Reactive Red X-3B and Congo Red, reaching as high as 26.46 mmol⋅g-1⋅h-1 and 32.85 mmol⋅g-1 ⋅h-1, respectively, which is 2-3 times greater than that observed in pure water and is 10 times greater than most reported studies. The great significance of this work lies in the potential for efficient H2 production through the utilization of wastewater.

2.
J Colloid Interface Sci ; 678(Pt C): 1036-1047, 2025 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-39332122

RESUMO

To improve the low energy density, low conductivity, and poor cycling stability of NiCo2S4 in supercapacitors, a two-step hydrothermal method was used to prepare a composite material of NiCo2S4 and carbon nanosheets (NiCo2S4/CNs). The electrochemical tests revealed a high specific capacitance of 1576 F g-1 at 1 A/g for the composite, and the NiCo2S4/CNs//AC asymmetric supercapacitor showed a energy density of 49.7 Wh kg-1 at 818 W kg-1. This study confirmed the phase transformation of NiCo2S4 during charge/discharge in alkaline solution through ex-situ X-ray diffraction (ex-situ XRD) for the first time, and proposed a potential reaction pathway. Moreover, Density Functional Theory (DFT) confirmed that the NiCo2S4/CNs heterostructure enhances OH- adsorption/desorption on Ni and Co active sites and improves electronic conductivity. In conclusion, this study advances the application of transition metal sulfide in high-performance energy storage.

3.
J Colloid Interface Sci ; 678(Pt A): 130-140, 2025 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-39182387

RESUMO

In the field of energy storage, supercapacitors have received extensive attention in recent years. However, achieving the expected electrochemical performance and energy density of supercapacitors is still a huge challenge. The design and synthesis of binder-free composite electrode with core-shell structure is an effective strategy to improve the electrochemical performance of supercapacitors. In this paper, a heterogeneous core-shell structured and binder-free electrode material MgCo2O4@Ni(OH)2 (MCO@NH) grown on nickel foam (NF) is prepared by a simple hydrothermal and oil bath method. The unique core-shell structure makes the MCO@NH have a large specific surface area, which provides abundant active sites for ion transport and storage, thereby improving the electrochemical performance. The MCO@NH/NF nanocomposite demonstrates a high specific capacitance (Cs) of 1583 F g-1 at 1 A/g. A solid-state asymmetric supercapacitor (ASC) assembled with MCO@NH/NF and active carbon (AC) exhibits excellent energy density (45 Wh kg-1 at 457.5 W kg-1) and outstanding capacitance (89.51 %) and coulombic efficiency (97.8 %) after 12,000 cycles, evidencing its good operation stability and potential practical applications. Therefore, the prepared core-shell MCO@NH/NF electrode can be a promising candidate for energy storage devices.

4.
J Environ Sci (China) ; 147: 451-461, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003061

RESUMO

Ketoprofen (KET), as a non-steroidal anti-inflammatory drug frequently detected in aqueous environments, is a threat to human health due to its accumulation and low biodegradability, which requires the transformation and degradation of KET in aqueous environments. In this paper, the reaction process of ozone-initiated KET degradation in water was investigated using density functional theory (DFT) method at the M06-2X/6-311++g(3df,2p)//M06-2X/6-31+g(d,p) level. The detailed reaction path of KET ozonation is proposed. The thermodynamic results show that ozone-initiated KET degradation is feasible. Under ultraviolet irradiation, the reaction of ozone with water can also produce OH radicals (HO·) that can react with KET. The degradation reaction of KET caused by HO· was further studied. The kinetic calculation illustrates that the reaction rate (1.99 × 10-1 (mol/L)-1 sec-1) of KET ozonation is relatively slow, but the reaction rate of HO· reaction is relatively high, which can further improve the degradation efficiency. On this basis, the effects of pollutant concentration, ozone concentration, natural organic matter, and pH value on degradation efficiency under UV/O3 process were analyzed. The ozonolysis reaction of KET is not sensitive to pH and is basically unaffected. Finally, the toxicity prediction of oxidation compounds produced by degradation reaction indicates that most of the degradation products are harmless, and a few products containing benzene rings are still toxic and have to be concerned. This study serves as a theoretical basis for analyzing the migration and transformation process of anti-inflammatory compounds in the water environment.


Assuntos
Cetoprofeno , Ozônio , Poluentes Químicos da Água , Cetoprofeno/química , Ozônio/química , Poluentes Químicos da Água/química , Cinética , Anti-Inflamatórios não Esteroides/química , Modelos Químicos , Purificação da Água/métodos
5.
J Environ Sci (China) ; 149: 465-475, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181659

RESUMO

VOCs (Volatile organic compounds) exert a vital role in ozone and secondary organic aerosol production, necessitating investigations into their concentration, chemical characteristics, and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric pollution. From July to October 2020, online monitoring was conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and reactivity. Additionally, the PMF (positive matrix factorization) method was utilized to identify the VOCs sources. Results indicated that the TVOCs (total VOCs) concentration was (96.7 ± 63.4 µg/m3), with alkanes exhibiting the highest concentration of (36.1 ± 26.4 µg/m3), followed by OVOCs (16.4 ± 14.4 µg/m3). The key active components were alkenes and aromatics, among which xylene, propylene, toluene, propionaldehyde, acetaldehyde, ethylene, and styrene played crucial roles as reactive species. The sources derived from PMF analysis encompassed vehicle emissions, solvent and coating sources, combustion sources, industrial emissions sources, as well as plant sources, the contribution of which were 37.80%, 27.93%, 16.57%, 15.24%, and 2.46%, respectively. Hence, reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/análise , China , Emissões de Veículos/análise , Cidades , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/prevenção & controle , Poluição do Ar/análise
6.
J Colloid Interface Sci ; 677(Pt B): 551-559, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39154447

RESUMO

Attributing to the advantages of intrinsic safety, high energy density, and good omnidirectional flexibility, fiber-shaped aqueous zinc ions batteries (FAZIBs), serving as energy supply devices, have multitude applications in flexible and wearable electronic devices. However, the detachment of active materials caused by bending stress generated during flexing process limits their practical application severely. To address the above issue, an effective integrated strategy employing microcracked activated cobalt hydroxide [A-Co(OH)2] cathode with protective coating of poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate) (PEDOT:PSS) was proposed in this work to enhance the cyclic and bending performances of FAZIBs. The microcracked A-Co(OH)2 cathode relieves stress concentration under bending conditions, while the PEDOT:PSS coating is responsible to maintain the structural integrity and prevents the detachment of A-Co(OH)2. The FAZIBs based on a gel electrolyte achieved a high energy density (173.5 Wh·kg-1) at a power density 90 W·kg-1 and a bending durability (94.4 % capacity retention after 500 cycles) as a consequence of the synergistic effect of microcracked A-Co(OH)2 cathode and the PEDOT:PSS coating. This work will offer a new approach for devising high-performance FAZIBs and promote the development of highly flexible and stable fiber-shaped batteries.

7.
J Colloid Interface Sci ; 677(Pt B): 780-794, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39173511

RESUMO

A new CeCO3OH@(hexagonal/cubic phases-CdS) (CeCO3OH@(H/C-CdS)) composite catalyst was facilely synthesized by a simple microinjection titration-stirring method, in which CdS nanoparticles were dispersed on the surface of CeCO3OH nanolines. The optimal conditions for the preparation of composite catalysts with high photocatalytic performance were determined by single-factor experiments and response surface experiments. Under these conditions, the degradation rate of 30 mL 2.000 g/L rhodamine B (Rh B) by CeCO3OH@(H/C-CdS) in a photocatalytic reaction for 1 h at 25 °C was up to 86.81 % and its degradation rate in a photocatalytic reaction for 150 min was up to 99.62 %. The degradation rate could be maintained above 80 % even after six times recycling. Especially, the photocatalytic degradation efficiency of 2.000 g/L Rh B on the composite catalyst under sunlight and at room temperature for 30 min reached 97.66 %. Meanwhile, the large size of CeCO3OH considerably alleviated the agglomeration of CdS, providing more adsorption and active sites for visible light-mediated degradation of Rh B. Importantly, the Z-scheme charge transfer realized by CdS and CeCO3OH enhanced the efficient separation of photogenerated electrons and holes, and successfully inhibited the recombination of photogenerated electrons with holes. At the same time, owing to the low energy band difference between the two phases of CdS, charge was transferred between the hexagonal and cubic phases, leaving more effective photogenerated charge to participate in the degradation of Rh B. The synergism of the heterophase junction and heterojunction and the presence of oxygen and sulfur vacancies considerably enhanced the degradation performance of the catalyst. Thus, this study provides a new strategy for the modification and enhanced visible-light catalysis performance of CdS-based catalysts.

8.
J Environ Manage ; 370: 122729, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369533

RESUMO

Elevated levels of total hardness in drinking water can readily result in scaling, which poses a threat to both the safety of water quality and the convenience of its use. While there is a wealth of research on the removal of calcium hardness, there is a dearth of studies focusing on the removal of magnesium hardness. In light of this, the present study employs modified induced crystallization softening (MICS) to delineate the removal pathways and mechanisms of magnesium hardness, and to investigate viable methods for its enhancement and application. Our research has determined that magnesium hardness can be effectively removed from water through the MICS, with the dosage of softening agents (NaOH) being a significant factor that influences this removal, whereas the fixed bed height within the fluidized bed exerts minimal impact on the process. In the low-dose stage (less than 250 mg/L), when the pH is below 10.0, up to 20% of magnesium hardness can be removed, predominantly through the crystallization of (Ca0.936Mg0.064)CO3. As the dosage increases to the moderate stage (250-400 mg/L), the conversion of excess bicarbonate (HCO3-) to carbonate (CO32-) in the water hinders further removal of magnesium hardness. In the high-dose stage (exceeding 400 mg/L), when the pH rises above 10.5, the removal rate of magnesium hardness can be enhanced to over 75%, with the crystallization of Mg(OH)2 being the primary removal mechanism. Density functional theory calculations, along with molecular dynamics simulations of cohesive energy and bond energy, substantiate the feasibility of the identified magnesium removal pathways. The addition of coagulants (FeCl3) and an decrease in the up-flow velocity can further augment the removal efficiency of magnesium hardness by promoting the crystallinity of Mg(OH)2 during the high-dose stage (exceeding 400 mg/L). In practical engineering applications, the strategic control of softening agent dosages enables the achievement of varying levels of magnesium hardness removal, tailored to specific water quality requirements.

9.
Med Phys ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39382851

RESUMO

BACKGROUND: In carbon ion radiotherapy, accurate measurement of the three-dimensional (3D) absorbed dose distribution is critical for effectively targeting tumors. Although micellar gel dosimeters exhibit considerable potential for measuring 3D absorbed dose distributions, few studies have focused on radiotherapy using carbon ion beams. PURPOSE: This study investigated the applicability of the surfactant hydrogel dosimeter (SHD), a micellar gel dosimeter, to measuring a 3D dose absorbed through carbon ion beam irradiation. METHODS: A cubic target region of 34 mm per side was established at a depth of 46 mm below the upper surface of an SHD specimen. Scanning irradiation was performed using a pencil beam of carbon ions at the Ion-beam Radiation Oncology Center in Kanagawa ("i-ROCK"), Japan, under irradiation conditions set by the treatment planning system ("Monaco for Carbon", Ver. 5.20, Elekta AB, Sweden) to create a spread-out Bragg peak within the target. The physical dose was set to 10 Gy at the isocenter, situated at the center of the target. The SHD responsiveness was measured twice using optical computed tomography (CT) ("Vista 15", Modus Medical Devices, Canada) for three irradiated specimens, and six types of measured optical attenuation coefficient (OAC) were obtained. To assess whether the OAC represented the absorbed dose expected in the treatment plan, we compared the relative distribution of the OAC and that of the absorbed dose. Relative fraction (RF) was used to measure the difference between the relative value of the OAC and that of the absorbed dose. Moreover, the distribution of OH radical (•OH) concentration obtained by Monte Carlo simulation ("PHITS" ver. 3.24 JAEA, Japan) and that of the OAC were compared. RESULTS: In the direction of beam travel, the relative distribution of the OAC was lower than that of the absorbed dose. This discrepancy could be attributed to a decrease in the concentration of •OH produced by irradiation owing to the recombination reaction, which does not accurately reflect the absorbed dose. By contrast, the distributions in the plane perpendicular to the beam travel were consistent. The RF increased from ± 3% to ± 13% along the beam travel direction. The small RF in the plane perpendicular to the beam travel could be attributed to the constant distribution of linear energy transfer, regardless of the irradiation position, and the generation of radicals proportionally to the absorbed dose. The increase in RF along the beam travel direction was ascribed to ring artifacts in the irradiated region. CONCLUSION: The measurement of the absorbed dose distribution in the beam travel direction should be improved. The observed discrepancy is attributed to the reduced reactivity of the SHD due to a high liner energy transfer near the Bragg peak. However, the absorbed dose distribution can be effectively evaluated in the plane perpendicular to the direction of beam travel.

10.
J Int Soc Sports Nutr ; 21(1): 2410426, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39350604

RESUMO

BACKGROUND: Vitamin D is associated with vascular function; however, the impact of different vitamin D levels on vascular elasticity following prolonged exercise remains uncertain. The primary objective of this study was to investigate the association of vitamin D levels with changes in peripheral pulse wave velocity (pPWV) and the magnitude of acute post-exercise hypotension (PEH) following prolonged endurance exercise in healthy young men. METHODS: All the participants were divided into two groups: the 25-hydroxyvitamin D (25(OH)D) sufficiency group (25(OH)D ≧50 nmol/L) and the deficiency group (25(OH)D < 50 nmol/L). A cardiopulmonary exercise test for maximal oxygen uptake (V.O2max) was performed on the graded cycling. The prolonged exercise was set at 60% V.O2max for 120 min of continuous riding on a stationary bicycle. The pPWV and blood pressure were measured at baseline and 0, 15, 30, 45, 60 min after prolonged endurance exercise. RESULTS: Post hoc analysis revealed that the vitamin D sufficient group had a greater magnitude of PEH than the deficiency group at post-45 min. Multiple linear regression analyses showed a significant correlation between 25(OH)D and both pPWV (p = 0.036) and PEH (p = 0.007), after adjusting for V.O2max, weight, height, and physical activity. In addition, the 25(OH)D deficiency group also had higher pPWV at post-15 min (5.41 ± 0.93 vs 4.84 ± 0.75 m/s), post-30 min (5.30 ± 0.77 vs 4.87 ± 0.50 m/s), post-45 min (5.56 ± 0.93 vs 5.05 ± 0.68 m/s) than the sufficiency group. CONCLUSIONS: There was a positive correlation between 25(OH)D levels and systolic PEH following prolonged endurance exercise. Individuals with sufficient 25(OH)D status may have better vascular elasticity and more efficient blood pressure regulation during exercise.


Assuntos
Resistência Física , Hipotensão Pós-Exercício , Análise de Onda de Pulso , Rigidez Vascular , Deficiência de Vitamina D , Vitamina D , Humanos , Masculino , Rigidez Vascular/fisiologia , Deficiência de Vitamina D/complicações , Adulto Jovem , Vitamina D/sangue , Vitamina D/análogos & derivados , Resistência Física/fisiologia , Hipotensão Pós-Exercício/fisiopatologia , Hipotensão Pós-Exercício/etiologia , Pressão Sanguínea , Teste de Esforço , Adulto , Exercício Físico/fisiologia , Consumo de Oxigênio
11.
Public Health Nutr ; 27(1): e224, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39465641

RESUMO

OBJECTIVE: This systematic review and meta-analysis examined the evidence for a potential relationship between vitamin D status and vitamin D supplementation on immune function biomarkers and prevention of acute respiratory tract infections (ARTI) in dark-skinned individuals. DESIGN: Six databases were searched (inception to December 2021) for randomised controlled trials (RCT) and observational studies. A narrative synthesis and random-effects meta-analysis were used to synthesise the findings. SETTING: Not applicable. PARTICIPANTS: Ethnic groups other than white, with or without a white comparator. RESULTS: After duplicates were removed, 2077 articles were identified for screening. A total of eighteen studies (n 36 707), including seven RCT and 11 observational studies, met the inclusion criteria, and three RCT (n 5778) provided sufficient data of high enough quality to be included in a meta-analysis. An inverse association between vitamin D status and at least one inflammatory biomarker in black adults was found in three studies, and vitamin D status was inversely associated with ARTI incidence in black and Indigenous groups in two studies. There was no significant effect of vitamin D supplementation on differences in ARTI incidence in ethnic minority groups (OR, 1·40; 95 % CI: 0·70, 2·79; P = 0·34), nor African American (OR, 1·77; 95 % CI: 0·51, 6·19; P = 0·37) or Asian/Pacific (OR, 1·08; 95 % CI: 0·77, 2·68; P = 0·66) subgroups. CONCLUSIONS: There is a lack of conclusive evidence supporting an association between vitamin D status and immune function or ARTI incidence in dark-skinned individuals. Further RCT in diverse ethnic populations are urgently needed.


Assuntos
Suplementos Nutricionais , Infecções Respiratórias , Vitamina D , Humanos , Infecções Respiratórias/prevenção & controle , Vitamina D/sangue , Vitamina D/administração & dosagem , Deficiência de Vitamina D/sangue , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Pigmentação da Pele/efeitos dos fármacos , Ensaios Clínicos Controlados Aleatórios como Assunto , Idoso , Biomarcadores/sangue , Etnicidade/estatística & dados numéricos , Doença Aguda
12.
Int J Mol Sci ; 25(20)2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39456696

RESUMO

Despite the recent development of improved methods of treating melanoma such as targeted therapy, immunotherapy or combined treatment, the number of new cases worldwide is increasing. It is well known that active metabolites of vitamin D3 and lumisterol (L3) exert photoprotective and antiproliferative effects on the skin, while UV radiation is a major environmental risk factor for melanoma. Thus, many natural metabolites and synthetic analogs of steroidal and secosteroidal molecules have been tested on various cancer cells and in animal models. In this study, we tested the anti-melanoma properties of several natural derivatives of vitamin D3 and L3 in comparison to 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). A significant decrease in melanoma cell proliferation and cell mobility was observed for selected derivatives, with (25R)-27-hydroxyL3 showing the highest potency (lowest IC50) in A375 cells but lower potency in SK-MEL-28 cells, whereas the parent L3 failed to inhibit proliferation. The efficacy (% inhibition) by 1,24,25(OH)3D3 and 1,25(OH)2D3 were similar in both cell types. 1,25(OH)2D3 showed higher potency than 1,24,25(OH)3D3 in SK-MEL-28 cells, but lower potency in A375 cells for the inhibition of proliferation. As for 1,25(OH)2D3, but not the other derivatives tested, treatment of melanoma cells with 1,24,25(OH)3D3 markedly increased the expression of CYP24A1, enhanced translocation of the vitamin D receptor (VDR) from the cytoplasm to the nucleus and also decreased the expression of the proliferation marker Ki67. The effects of the other compounds tested were weaker and occurred only under certain conditions. Our data indicate that 1,24,25(OH)3D3, which has undergone the first step in 1,25(OH)2D3 inactivation by being hydroxylated at C24, still shows anti-melanoma properties, displaying higher potency than 1,25(OH)2D3 in SK-MEL-28 cells. Furthermore, hydroxylation increases the potency of some of the lumisterol hydroxy-derivatives, as in contrast to L3, (25R)-27(OH)L3 effectively inhibits proliferation and migration of the human malignant melanoma cell line A375.


Assuntos
Antineoplásicos , Proliferação de Células , Melanoma , Vitamina D , Humanos , Melanoma/metabolismo , Melanoma/tratamento farmacológico , Melanoma/patologia , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Vitamina D/farmacologia , Vitamina D/análogos & derivados , Receptores de Calcitriol/metabolismo , Movimento Celular/efeitos dos fármacos , Colecalciferol/farmacologia , Colecalciferol/análogos & derivados , Vitamina D3 24-Hidroxilase/metabolismo , Vitamina D3 24-Hidroxilase/genética , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
13.
Int J Mol Sci ; 25(20)2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39457047

RESUMO

Clinical trial results indicate that statin therapy aimed at normalising the lipid profile can prevent and reduce the risk of cardiovascular events. Both LDL and HDL consist of several subfractions, with only the smallest and densest subfractions being the most atherogenic. We examine the effect of Atorvastatin treatment not only on basic lipid profile parameters but also atherogenic lipoprotein subfractions and 25(OH)D levels in patients after the first acute myocardial infarction. The study population had not previously received lipid-lowering medications. Serum 25(OH)D concentration was determined by direct competitive immunochemiluminescent assays. Lipoprotein subfractions, including VLDL, IDL-C, IDL-B, and IDL-A, as well as LDL1, LDL2 (large LDL), and LDL3-7 (sdLDL), were measured in serum (Lipoprint® system). Almost all patients had 25(OH)D deficiency. Atorvastatin primarily reduced strongly atherogenic sdLDL and decreased the less atherogenic large LDL subfractions. A statistically significant reduction in VLDL cholesterol and IDL fractions was also observed. Analysing LDL subfractions provides a more detailed insight into lipid metabolism and enables the identification of patients with a more atherogenic phenotype. LDL subfractions may thus become not only more accurate prognostic biomarkers but also targets for lipid-lowering therapy. Vitamin D deficiency is associated with atherogenic dyslipidaemia, particularly high levels of sdLDL.


Assuntos
Atorvastatina , Lipoproteínas LDL , Infarto do Miocárdio , Vitamina D , Humanos , Atorvastatina/uso terapêutico , Masculino , Vitamina D/sangue , Pessoa de Meia-Idade , Feminino , Infarto do Miocárdio/sangue , Infarto do Miocárdio/tratamento farmacológico , Idoso , Lipoproteínas LDL/sangue
14.
Front Med (Lausanne) ; 11: 1431170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39444820

RESUMO

Purpose: This study aimed to assess the causal relationships between vitamin D levels and ocular disorders. Methods: Independent genetic variables were obtained from genome-wide association studies (GWAS) and publicly available databases. The summary statistics for 25-hydroxyvitamin D (25(OH)D) were obtained from two large-scale GWAS studies, with sample sizes of 324,105 and 417,580 European individuals. The genetic variants of myopia, primary open angle glaucoma (POAG), anterior iridocyclitis, senile cataract, diabetic retinopathy (DR), retinal vein occlusion (RVO), wet age-related macular degeneration (WAMD) and optic neuritis were extracted from the latest release of FinnGen consortium, which contains genome data from Finnish participants. Subsequently, Mendelian randomization (MR) analyses were conducted to obtain effect estimates. Additionally, we performed multivariable MR analysis and mediation analysis to validate the results. Results: In the discovery dataset, genetically predicted vitamin D concentration was found to be causally associated with an increased risk of WAMD, (odd ratio (OR) = 1.35, 95% confidence interval (CI) = 1.09-1.67, P IVW = 0.005). However, no causal effects of genetically predisposed vitamin D levels on the risk of most types of ocular disorders were observed. Reverse MR revealed no causal relationships between the ocular diseases and vitamin D concentrations. The MR analyses of the validation dataset yielded consistent results. Additionally, the causal effect of vitamin D levels on the risk of WAMD remained significant after adjusting for potential confounders in the multivariable MR analysis (OR = 1.86, 95% CI = 1.26-2.73, P IVW = 0.002). Conclusion: Our MR analysis results provide robust evidence of a causal relationship between genetically predicted 25(OH)D levels and an increased risk of WAMD in European population. These findings offer important insights into the management and control of ocular disorders.

15.
Environ Sci Technol ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39445870

RESUMO

Monoterpenes, the second most abundant biogenic volatile organic compounds globally, are crucial in forming secondary organic aerosols, making their oxidation mechanisms vital for addressing climate change and air pollution. This study utilized cyclohexene as a surrogate to explore first-generation products from its ozonolysis through laboratory experiments and mechanistic modeling. We employed proton transfer reaction mass spectrometry with NH4+ ion sources (NH4+-CIMS) and a custom-built OH calibration source to quantify organic peroxy radicals (RO2) and closed-shell species. Under near-real atmospheric conditions in a Potential Aerosol Mass-Oxidation Flow Reactor, we identified 30 ozonolysis products, expanding previous data sets of low-oxygen compounds. Combined with simulations based on the Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere and relevant literature, our results revealed that OH dominates over ozone in cyclohexene oxidation at typical atmospheric oxidant levels with H-abstraction contributing 30% of initial RO2 radicals. Highly oxidized molecules primarily arise from RO2 autoxidation initiated by ozone, and at least 15% of ozone oxidation products follow the overlooked nonvinyl hydroperoxides pathway. Gaps remain especially in understanding RO2 cross-reactions, and the structural complexity of monoterpenes further complicates research. As emissions decrease and afforestation increases, understanding these mechanisms becomes increasingly critical.

16.
Prim Care Diabetes ; 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39448331

RESUMO

BACKGROUND: Immigrants from the Middle East (ME) have a higher prevalence of type 2 diabetes (T2D) compared to the native-born Swedish population. In individuals free from T2D, ME immigrants are more insulin resistant and have lower levels of adjusted insulin secretion (Disposition index, DIo) compared to Swedish-born individuals. The ethnic differences are not fully explained by traditional risk factors. This has raised the question as to whether hormonal factors other than insulin are involved, contributing to higher T2D risk in ME immigrants. AIMS: In ME immigrants at high risk of developing T2D, we aimed to study the effect of a randomized culturally adapted lifestyle intervention on the levels of Vitamin D (25(OH)D), insulin-like growth factor 1 (IGF-1), Pro-neurotensin (Pro-NT) and Adiponectin. Furthermore, we aimed to study if the effect of the intervention was associated to these hormones, or if a direct effect of the intervention remained after accounting for these. METHODS: In this culturally adapted randomized controlled trial of four months duration, eligible ME immigrants at high risk of developing T2D identified in the MEDIM cohort were invited to participate. The intervention group (N= 35) received a culturally adapted lifestyle intervention program consisting of seven group sessions and cooking classes. The control group (N= 32) were given treatment as usual with oral and written information to improve their lifestyle habits. Using mixed models' linear regression analysis, the changes in the levels of 25(OH)D, IGF-1, Adiponectin and Pro-NT were assessed by comparing the groups and we further studied the effects of the changes on insulin action and secretion. RESULTS: The adjusted levels of 25(OH)D significantly increased in the intervention group compared to the control group (ß for the effect of the intervention on 25(OH)D: 0.061, 95 % CI 0.009-0.113, P = 0.023). The increase in insulin sensitivity index (ISI) observed in the intervention compared to the control group was altered after adjusting for 25(OH)D: 0.129, 95 % CI -0.016-0.274, P = 0.078). IGF-1, Adiponectin and Pro-NT did not significantly influence the change over time concerning insulin secretion. CONCLUSION: Lifestyle intervention increases the adjusted levels of 25(OH)D. Moreover, the effect of the lifestyle intervention on insulin action and secretion was altered when adjusting for 25(OH)D.

17.
ACS Sens ; 9(10): 5445-5453, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39364916

RESUMO

Cardiovascular disease (CVD) is a chronic disease characterized by the accumulation of lipids and fibrous tissue within the arterial walls, potentially leading to vascular obstruction and an increased risk of heart disease and stroke. Hydroxyl radicals play a significant role in the formation and progression of CVD as they can instigate lipid peroxidation, resulting in cellular damage and inflammatory responses. However, precisely detecting hydroxyl radicals in CVD lesions presents significant challenges due to their high reactivity and short lifespan. Herein, we present the development and application of a novel activatable optical probe, Cy-OH-LP, designed to detect hydroxyl radicals in lipid-rich environments specifically. Built on the Cy7 molecular skeleton, Cy-OH-LP exhibits near-infrared absorption and fluorescence characteristics, and its specific response to hydroxyl radicals enables a turn-on signal in both photoacoustic and fluorescence spectra. The probe demonstrated excellent selectivity and stability in various tests. Furthermore, Cy-OH-LP was successfully applied in an in vivo model to detect hydroxyl radicals in mouse models, providing a potential tool for diagnosing and monitoring AS. The biosafety of Cy-OH-LP was also verified, showing low cytotoxicity and no significant organ damage in mice. The findings suggest that Cy-OH-LP is a promising tool for the specific detection of hydroxyl radicals in lipid-rich environments, providing new possibilities for research and clinical applications in the field of oxidative stress-related diseases.


Assuntos
Radical Hidroxila , Técnicas Fotoacústicas , Animais , Radical Hidroxila/análise , Radical Hidroxila/química , Radical Hidroxila/metabolismo , Técnicas Fotoacústicas/métodos , Humanos , Camundongos , Corantes Fluorescentes/química , Carbocianinas/química , Doenças Cardiovasculares , Masculino
18.
Biology (Basel) ; 13(10)2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39452065

RESUMO

Metagenomic binning is a crucial step in metagenomic research. It can aggregate the genome sequences belonging to the same microbial species into independent bins. Most existing methods ignore the semantic information of contigs and lack effective processing of tetranucleotide frequency, resulting in insufficient and complex feature information extracted for binning and poor binning results. To address the above problems, we propose CedtBin, a metagenomic binning method based on contig embedding and decomposed tetranucleotide frequency. First, the improved BERT model is used to learn the contigs to obtain their embedding representation. Secondly, the tetranucleotide frequencies are decomposed using a non-negative matrix factorization (NMF) algorithm. After that, the two features are spliced and input into the clustering algorithm for binning. Considering the sensitivity of the DBSCAN clustering algorithm to input parameters, in order to solve the drawbacks of manual parameter input, we also propose an Annoy-DBSCAN algorithm that can adaptively determine the parameters of the DBSCAN algorithm. This algorithm uses Approximate Nearest Neighbors Oh Yeah (Annoy) and combines it with a grid search strategy to find the optimal parameters of the DBSCAN algorithm. On simulated and real datasets, CedtBin achieves better binning results than mainstream methods and can reconstruct more genomes, indicating that the proposed method is effective.

19.
Biology (Basel) ; 13(10)2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39452140

RESUMO

The interaction of the SARS-CoV-2 spike protein with membrane-bound angiotensin-converting enzyme-2 (ACE-2) receptors in epithelial cells facilitates viral entry into human cells. Despite this, ACE-2 exerts significant protective effects against coronaviruses by neutralizing viruses in circulation and mitigating inflammation. While SARS-CoV-2 reduces ACE-2 expression, vitamin D increases it, counteracting the virus's harmful effects. Vitamin D's beneficial actions are mediated through complex molecular mechanisms involving innate and adaptive immune systems. Meanwhile, vitamin D status [25(OH)D concentration] is inversely correlated with severity, complications, and mortality rates from COVID-19. This study explores mechanisms through which vitamin D inhibits SARS-CoV-2 replication, including the suppression of transcription enzymes, reduced inflammation and oxidative stress, and increased expression of neutralizing antibodies and antimicrobial peptides. Both hypovitaminosis D and SARS-CoV-2 elevate renin levels, the rate-limiting step in the renin-angiotensin-aldosterone system (RAS); it increases ACE-1 but reduces ACE-2 expression. This imbalance leads to elevated levels of the pro-inflammatory, pro-coagulatory, and vasoconstricting peptide angiotensin-II (Ang-II), leading to widespread inflammation. It also causes increased membrane permeability, allowing fluid and viruses to infiltrate soft tissues, lungs, and the vascular system. In contrast, sufficient vitamin D levels suppress renin expression, reducing RAS activity, lowering ACE-1, and increasing ACE-2 levels. ACE-2 cleaves Ang-II to generate Ang(1-7), a vasodilatory, anti-inflammatory, and anti-thrombotic peptide that mitigates oxidative stress and counteracts the harmful effects of SARS-CoV-2. Excess ACE-2 molecules spill into the bloodstream as soluble receptors, neutralizing and facilitating the destruction of the virus. These combined mechanisms reduce viral replication, load, and spread. Hence, vitamin D facilitates rapid recovery and minimizes transmission to others. Overall, vitamin D enhances the immune response and counteracts the pathological effects of SARS-CoV-2. Additionally, data suggests that widely used anti-hypertensive agents-angiotensin receptor blockers and ACE inhibitors-may lessen the adverse impacts of SARS-CoV-2, although they are less potent than vitamin D.

20.
Int J Biol Macromol ; 282(Pt 1): 136759, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39454899

RESUMO

Two thermochromic poplar-based composites, TPC-1 and TPC-2, were fabricated using a crystal violet lactone (CVL)/lactic acid/myristyl alcohol ternary mixture. The mass ratios for TPC-1 and TPC-2 were 10: 3: 200 and 10: 80: 200, respectively. TPC-1 exhibits a common thermochromic property, reversibly changing color from blue to the natural hue of poplar within the temperature range of 28-48 °C. In contrast, TPC-2 demonstrates a novel thermochromic behavior, shifting from light blue to dark blue within the range of 30-52 °C. This work elucidates the correlations between the distinctive mass ratios in the ternary mixtures, the resulting CVL structures, and the consequent thermochromic properties. The blue TPC-1 exhibits an open lactone ring with a HO-C=O in its CVL structure. Similarly, the light-blue TPC-2 displays an open lactone ring with a HO-C=O. However, the dark-blue TPC-2 features an open lactone ring with a HO-C=O and a C-O-C. TPC-2 is a ternary mixture encapsulated with a poplar-based cellulose/lignin/SiO2 framework. This integrated framework chemically interacts with the ternary mixture, enhancing phase-changing properties, heat-saving capabilities and mechanical properties of TPC-2. Consequently, TPC-2 is a promising candidate for applications as a temperature-responsive, thermal energy-storing, and structural material in building interiors.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA