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1.
Food Funct ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967438

RESUMO

The stability of bioactive peptides under various food processing conditions is the basis for their use in industrial manufacturing. This study aimed to identify natural ACE inhibitors with excellent stability and investigate their physicochemical properties and putative molecular mechanisms. Five novel ACE inhibitory peptides (QDPLFPL, FPGVSPF, SPAQLLPF, LVPYRP, and WYWPQ) were isolated and identified using RP-HPLC and Nano LC-MS/MS with foxtail millet protein hydrolysates as the raw material. These peptides are non-toxic and exhibit strong ACE inhibitory activity in vitro (IC50 values between 0.13 mg mL-1 and 0.56 mg mL-1). In addition to QDPLFPL, FPGVSPF, SPAQLLPF, LVPYRP, and WYWPQ have excellent human intestinal absorption. Compared to FPGVSPF and SPAQLLPF, the stable helical structure of LVPYRP and WYWPQ allows them to maintain high stability under conditions that mimic gastrointestinal digestion and various food processing (temperatures, pH, sucrose, NaCl, citric acid, sodium benzoate, Cu2+, Zn2+, K+, Mg2+, Ca2+). The results of molecular docking and molecular dynamics simulation suggest that LVPYRP has greater stability and binding capacity to ACE than WYWPQ. LVPYRP might attach to the active pockets (S1, S2, and S1') of ACE via hydrogen bonds and hydrophobic interactions, then compete with Zn2+ in ACE to demonstrate its ACE inhibitory activity. The binding of LVPYRP to ACE enhances the rearrangement of ACE's active structural domains, with electrostatic and polar solvation energy contributing the most energy to the binding. Our findings suggested that LVPYRP derived from foxtail millet protein hydrolysates has the potential to be incorporated into functional foods to provide antihypertensive benefits.

2.
Research (Wash D C) ; 7: 0391, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887277

RESUMO

Dipeptidyl peptidase-IV (DPP-4) enzyme inhibitors are a promising category of diabetes medications. Bioactive peptides, particularly those derived from bovine milk proteins, play crucial roles in inhibiting the DPP-4 enzyme. This study describes a comprehensive strategy for DPP-4 inhibitory peptide discovery and validation that combines machine learning and virtual proteolysis techniques. Five machine learning models, including GBDT, XGBoost, LightGBM, CatBoost, and RF, were trained. Notably, LightGBM demonstrated superior performance with an AUC value of 0.92 ± 0.01. Subsequently, LightGBM was employed to forecast the DPP-4 inhibitory potential of peptides generated through virtual proteolysis of milk proteins. Through a series of in silico screening process and in vitro experiments, GPVRGPF and HPHPHL were found to exhibit good DPP-4 inhibitory activity. Molecular docking and molecular dynamics simulations further confirmed the inhibitory mechanisms of these peptides. Through retracing the virtual proteolysis steps, it was found that GPVRGPF can be obtained from ß-casein through enzymatic hydrolysis by chymotrypsin, while HPHPHL can be obtained from κ-casein through enzymatic hydrolysis by stem bromelain or papain. In summary, the integration of machine learning and virtual proteolysis techniques can aid in the preliminary determination of key hydrolysis parameters and facilitate the efficient screening of bioactive peptides.

3.
Carbohydr Polym ; 339: 122209, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823899

RESUMO

The escalating global health concern arises from chronic wounds induced by bacterial infections, posing a significant threat to individuals. Consequently, an imperative exist for the development of hydrogel dressings to facilitate prompt wound monitoring and efficacious wound management. To this end, pH-sensitive bromothymol blue (BTB) and pH-responsive drug tetracycline hydrochloride (TH) were introduced into the polysaccharide-based hydrogel to realize the integration of wound monitoring and controlled treatment. Polysaccharide-based hydrogels were formed via a Schiff base reaction by cross-linking carboxymethyl chitosan (CMCS) on an oxidized sodium alginate (OSA) skeleton. BTB was used as a pH indicator to monitor wound infection through visual color changes visually. TH could be dynamically released through the pH response of the Schiff base bond to provide effective treatment and long-term antibacterial activity for chronically infected wounds. In addition, introducing polylactic acid nanofibers (PLA) enhanced the mechanical properties of hydrogels. The multifunctional hydrogel has excellent mechanical, self-healing, injectable, antibacterial properties and biocompatibility. Furthermore, the multifaceted hydrogel dressing under consideration exhibits noteworthy capabilities in fostering the healing process of chronically infected wounds. Consequently, the research contributes novel perspectives towards the advancement of intelligent and expeditious bacterial infection monitoring and dynamic treatment platforms.


Assuntos
Alginatos , Antibacterianos , Bandagens , Quitosana , Hidrogéis , Nanofibras , Cicatrização , Nanofibras/química , Hidrogéis/química , Hidrogéis/farmacologia , Cicatrização/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Concentração de Íons de Hidrogênio , Quitosana/química , Quitosana/análogos & derivados , Quitosana/farmacologia , Alginatos/química , Animais , Staphylococcus aureus/efeitos dos fármacos , Tetraciclina/química , Tetraciclina/farmacologia , Camundongos , Infecção dos Ferimentos/tratamento farmacológico , Polissacarídeos/química , Escherichia coli/efeitos dos fármacos , Bases de Schiff/química , Testes de Sensibilidade Microbiana , Humanos
4.
J Mater Chem B ; 12(8): 2042-2053, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38315081

RESUMO

Designing wound dressings necessitates the crucial considerations of maintaining a moist environment and implementing effective bacterial control. Furthermore, developing a three-dimensional framework emulating the extracellular matrix (ECM) confers advantages in fostering cellular migration and proliferation. Inspired by this, hydrogel/nanofiber composites have been demonstrated as promising materials for wound dressings. The composites also overcome the disadvantages of poor mechanical properties and rapid release of traditional pure hydrogels. In this study, we constructed a calcium alginate hydrogel/polylactic acid nanofiber (CAH/PLANF) composite with an interpenetrated network. Additionally, the synthesis of zeolitic imidazolate framework-8 (ZIF-8) incorporated into the composite system endowed the system with enhanced mechanical properties and photodynamic antibacterial attributes. The obtained composite patch (ZIF-8@CAH/PLANF) exhibited excellent swelling, strong mechanical properties, low cytotoxicity, and durable photodynamic antibacterial effect with an antibacterial efficacy of higher than 99.99%. Finally, bacterial infection and wound healing properties were investigated in vivo, and the ZIF-8@CAH/PLANF patch was proven to have the ability to fight infection and accelerate wound healing.


Assuntos
Nanofibras , Zeolitas , Hidrogéis/farmacologia , Cicatrização , Antibacterianos/farmacologia
5.
Int J Biol Macromol ; 254(Pt 1): 127725, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287585

RESUMO

Resistant starch (RS) has been extensively studied because of its beneficial effects on gut microbiota. In this study, four RSs obtained through various preparation processes were utilized for in vitro fermentation, and their structural characteristics before and after fermentation were determined using chromatography, Fourier infrared spectroscopy, and scanning electron microscopy (SEM). It was observed that these RSs can be classified into two categories based on their fermentation and structural features. The autoclaving RS (ARS) and extruding RS (ERS) were classified as Class I Microbiome Community (MC-I), characterized by a higher proportion of butyrate and its producers, including unclassified_g_Megasphaera and Megasphaera elsdenii. While microwaving RS (MRS) and ultrasound RS (URS) belonged to Class II Microbiome Community (MC-II), marked by a higher proportion of acetate and its producer, Bifidobacterium pseudocatenulatum DSM 20438. MC-I had a lower molecular weight, shorter chain length, more chains with degree of polymerization (DP) 36-100, and a more ordered structure than MC-II. Furthermore, SEM observations revealed distinct degradation patterns between MC-I and MC-II, which may be attributed to their surface structural characteristics. These findings imply that the preparation methods employed for RS can determine its multilevel structural characteristics, and consequently influence its physiological properties.


Assuntos
Microbioma Gastrointestinal , Microbiota , Fermentação , Amido Resistente/metabolismo , Amido/química , Fezes/microbiologia , Ácidos Graxos Voláteis/metabolismo
6.
Nutrients ; 15(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37836470

RESUMO

The efficacy and mechanism of highland barley in the treatment of atherosclerosis have received little attention. Herein, we aimed to explore whether highland barley supplementation can prevent atherosclerosis progression and improve gut microbiota disorder in apolipoprotein E knockout (ApoE-/-) mice. Male ApoE-/- mice were fed a high-fat diet with whole-grain highland barley (WHB) or refined highland barley for 18 weeks. WHB substantially inhibited the formation of atherosclerotic plaques, reduced serum tumor necrosis factor-α, and downregulated the expression of NLRP3 in the aorta. Furthermore, the 16S rRNA analysis revealed that highland barley supplementation helped to restore the dysregulation of the gut microbiota, as evidenced by an increase in the relative abundance of specific beneficial bacteria known for their anti-inflammatory properties, such as Lachnospiraceae, Lactobacillus, Muribaculaceae, and Bifidobacterium. Highland barley supplementation might alleviate atherosclerotic plaque formation by modulating the NLRP3 inflammasome pathway and the synthesis of anti-inflammatory metabolites by the gut microbiota.


Assuntos
Aterosclerose , Microbioma Gastrointestinal , Hordeum , Placa Aterosclerótica , Masculino , Animais , Camundongos , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , RNA Ribossômico 16S , Aterosclerose/metabolismo , Anti-Inflamatórios/uso terapêutico , Apolipoproteínas E/genética , Camundongos Endogâmicos C57BL , Dieta Hiperlipídica/efeitos adversos
7.
Mater Horiz ; 10(11): 5161-5176, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37712534

RESUMO

Solar-driven desalination (SDD) is a promising technology for addressing water scarcity. However, how to overcome the trade-off between water transportation and heat supply of the evaporator to achieve a high evaporation rate and good salt tolerance simultaneously remains a challenge. Here, a novel all-in-one multi-functional SDD evaporator undergoing gradient heating is used. This evaporator incorporates a hydrophilic PDA (polydopamine)@CNT(carbon nanotube)/PVA (polyvinyl alcohol) aerogel with vertically aligned structures as the water evaporation layer, enabling rapid water transportation. Surrounding the evaporation layer, there is a photothermal hydrophobic CCP (cotton/CNT/polydimethylsiloxane) film that serves as the heating layer, enhancing the heat supply to the evaporation layer. This innovative design strikes a favorable balance between water transportation and heat supply, facilitating high evaporation rates and good salt tolerance simultaneously, while also maximizing electricity generation. Due to the wettability difference between the evaporation layer (PVA aerogel) and heating layer (CCP film), a record stable temperature gradient of nearly 70 °C was formed between the CCP film and the PVA aerogel under 1 sun irradiation, so that heat on the high-temperature CCP film was continuously transferred to the low-temperature aerogel through its thermal conductive network, leading to a high evaporation rate of 6.96 kg m-2 h-1 under 1 sun irradiation in 5.0 wt% sodium chloride (NaCl) brine (higher than the world average seawater salinity (3.5 wt%)). Meanwhile, high flux directional flow of brine generated 130 mV stable voltage and 120 µA circuit current. Furthermore, the evaporator illustrates good stability for consecutive 7 days of testing and shows industry-leading comprehensive performance of SDD in actual use. More importantly, it was tested in real Bohai seawater under weak natural light, and fresh water generated can meet the recommended daily intake of water for 2.6 households and the simultaneously generated voltage reaches above 60 mV. In addition, the evaporator exhibits good adsorption capacity for heavy metals and dye molecules. This simple and universal solar evaporation structure is suitable for the assembly of gradient thermal structures for most solar thermal materials reported in the literature, which provides a new route for maximizing the use of solar energy for freshwater and electricity generation.

8.
Gels ; 9(9)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37754375

RESUMO

Hydrogels are widely used in wound dressings due to their moisturizing properties and biocompatibility. However, traditional hydrogel dressings cannot monitor wounds and provide accurate treatment. Recent advancements focus on hydrogel dressings with integrated monitoring and treatment functions, using sensors or intelligent materials to detect changes in the wound microenvironment. These dressings enable responsive treatment to promote wound healing. They can carry out responsive dynamic treatment in time to effectively promote wound healing. However, there is still a lack of comprehensive reviews of hydrogel wound dressings that incorporate both wound micro-environment monitoring and treatment functions. Therefore, this review categorizes hydrogel dressings according to wound types and examines their current status, progress, challenges, and future trends. It discusses various wound types, including infected wounds, burns, and diabetic and pressure ulcers, and explores the wound healing process. The review presents hydrogel dressings that monitor wound conditions and provide tailored treatment, such as pH-sensitive, temperature-sensitive, glucose-sensitive, pressure-sensitive, and nano-composite hydrogel dressings. Challenges include developing dressings that meet the standards of excellent biocompatibility, improving monitoring accuracy and sensitivity, and overcoming obstacles to production and commercialization. Furthermore, it provides the current status, progress, challenges, and future trends in this field, aiming to give a clear view of its past, present, and future.

9.
Food Chem ; 418: 135980, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36989644

RESUMO

Nutraceuticals which are abundant in foods have attracted much attention due to their bioactive activities of anti-obesity, anti-hyperlipidemia and anti-atherosclerosis. Unfortunately, the poor bioavailability severely undermines their envisioned benefits. Therefore, there is an urgent need to develop suitable delivery systems to promote the benefits of their biological activity. Targeted drug delivery system (TDDS) is a novel drug delivery system that can selectively concentrate drugs on targets in the body, improve the bioavailability of agents and reduce side effects. This emerging drug delivery system provides a new strategy for the treatment of obesity with nutraceuticals and would be a promising alternative to be widely used in the food field. This review summarizes the recent studies on the application in the targeted delivery of nutraceuticals for treating obesity and its related complications, especially the available receptors and their corresponding ligands for TDDS and the evaluation methods of the targeting ability.


Assuntos
Suplementos Nutricionais , Obesidade , Humanos , Obesidade/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos
10.
Food Chem ; 404(Pt B): 134690, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36323032

RESUMO

As a potential and effective substitute for the drugs of antihypertension, the food-derived antihypertensive peptides have arisen great interest in scholars recently. However, the traditional screening methods for antihypertensive peptides are at considerable expense and laborious, which blocks the exploration of available antihypertensive peptides. In our study, we reported the use of a protein-specific deep learning model called ProtBERT to screen for antihypertensive peptides. Compared to other deep learning models, ProrBERT reached the highest the area under the receiver operating characteristic curve (AUC) value of 0.9785. In addition, we used ProtBERT to screen candidate peptides in soybean protein isolate (SPI), followed by molecular docking and in vitro validation, and eventually found that peptides LVPFGW (IC50 = 20.63 µM), VSFPVL (2.57 µM), and VLPF (5.78 µM) demonstrated the good antihypertensive activity. Deep learning such as ProtBERT will be a useful tool for the rapid screening and identification of antihypertensive peptides.


Assuntos
Anti-Hipertensivos , Aprendizado Profundo , Anti-Hipertensivos/química , Proteínas de Soja , Inibidores da Enzima Conversora de Angiotensina/química , Simulação de Acoplamento Molecular , Peptídeos/farmacologia , Peptídeos/química
11.
Nutrients ; 14(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36297020

RESUMO

Capsaicin is a pungent alkaloid abundantly present in peppers with outstanding biological activities, including the anti-atherosclerosis effect. Previous studies revealed that gut microbiota played an important role in the beneficial effects of capsaicin, but whether it is essential for the anti-atherosclerosis effect of capsaicin is unclear. This study evaluated the anti-atherosclerosis effect of capsaicin in ApoE-/- mice and further explored the role of depleting gut microbiota in the improvement of atherosclerosis. The results showed that capsaicin administration could prevent the development of atherosclerosis and improve serum lipids and inflammation, while antibiotic intervention abolished the alleviation of atherosclerosis by capsaicin. In addition, capsaicin administration could significantly increase the abundance of Turicibacter, Odoribacter, and Ileibacterium in feces, and decrease the abundance of deoxycholic acid, cholic acid, hypoxanthine, and stercobilin in cecal content. Our study provides evidence that gut microbiota plays a critical role in the anti-atherosclerosis effect of capsaicin.


Assuntos
Aterosclerose , Capsaicina , Microbioma Gastrointestinal , Animais , Camundongos , Antibacterianos/farmacologia , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Aterosclerose/microbiologia , Capsaicina/farmacologia , Ácido Cólico , Ácido Desoxicólico , Dieta Hiperlipídica/efeitos adversos , Hipoxantinas , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE
12.
Front Nutr ; 9: 918696, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782919

RESUMO

Adzuki bean is widely consumed in East Asia. Although the positive effects of its biologically active ingredients on obesity have been confirmed, the role of whole cooked adzuki bean in preventing obesity and the relationship between the effects and gut microbiota remain unclear. Mice were fed either a low-fat diet (LFD) or high-fat diet (HFD) with or without 15% cooked adzuki bean for 12 weeks. Cooked adzuki bean significantly inhibited weight gain and hepatic steatosis, reduced high levels of serum triacylglycerol (TG), alanine aminotransferase (ALT), and aspartate aminotransferase (AST), and alleviated systemic inflammation and metabolic endotoxemia in mice fed a HFD. Importantly, cooked adzuki bean regulated gut microbiota composition, decreased the abundance of lipopolysaccharide (LPS)-producing bacteria (Desulfovibrionaceae,Helicobacter,and Bilophila), and HFD-dependent taxa (Deferribacteraceae, Ruminiclostridium_9, Ruminiclostridium, Mucispirillum, Oscillibacter, Enterorhabdus, Tyzzerella, Anaerotruncus, Intestinimonas, unclassified_f_Ruminococcaceae, Ruminiclostridium_5, and Ruminococcaceae), and enriched Muribaculaceae, norank_f_Muribaculaceae, Anaeroplasma, Lachnospiraceae_NK4A136_group, and Lachnospiraceae to alleviate inflammation and metabolic disorders induced by HFD. These findings provide new evidence for understanding the anti-obesity effect of cooked adzuki bean.

13.
Polymers (Basel) ; 14(12)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35746080

RESUMO

Recently, MnO2-coated polymeric filters have shown promising performance in room-temperature formaldehyde abatement. However, a commonly known concern of MnO2/polymer composites is either MnO2 crystal encapsulation or weak adhesion. This work reports a low-cost high-throughput and green strategy to produce binder-free MnO2-nonwoven composite air filters. The production approach is energy saving and environmentally friendly, which combines MnO2 crystal coating on bicomponent polyolefin spunbond nonwovens and subsequent heat immobilizing of crystals, followed by the removal of weakly bonded MnO2. The binder-free MnO2-nonwoven composites show firm catalyst-fiber adhesion, a gradient porous structure, and excellent formaldehyde removal capability (94.5% ± 0.4%) at room temperature, and the reaction rate constant is 0.040 min-1. In contrast to the MnO2-nonwoven composites containing organic binders, the HCHO removal of binder-free filters increased by over 4%. This study proposes an alternative solution in producing catalyst/fabric composite filters for formaldehyde removal.

14.
Nutrients ; 13(8)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34444794

RESUMO

Although studies have examined the association between habitual consumption of sugar- (SSBs) and artificially sweetened beverages (ASBs) and health outcomes, the results are inconclusive. Here, we conducted a dose-response meta-analysis of prospective cohort studies in order to summarize the relationship between SSBs and ASBs consumption and risk of type 2 diabetes (T2D), cardiovascular diseases (CVDs), and all-cause mortality. All relevant articles were systematically searched in PubMed, Embase, and Ovid databases until 20 June 2020. Thirty-four studies met the inclusion criteria and were eligible for analysis. Summary relative risks (RRs) and 95% confidence intervals (95% CI) were estimated using random effects or fixed-effects model for highest versus lowest intake categories, as well as for linear and non-linear relationships. With each additional SSB and ASB serving per day, the risk increased by 27% (RR: 1.27, 95%CI: 1.15-1.41, I2 = 80.8%) and 13% (95%CI: 1.03-1.25, I2 = 78.7%) for T2D, 9% (RR: 1.09, 95%CI: 1.07-1.12, I2 = 42.7%) and 8% (RR: 1.08, 95%CI: 1.04-1.11, I2 = 45.5%) for CVDs, and 10% (RR: 1.10, 95%CI: 0.97-1.26, I2 = 86.3%) and 7% (RR: 1.07, 95%CI: 0.91-1.25, I2 = 76.9%) for all-cause mortality. Linear relationships were found for SSBs with T2D and CVDs. Non-linear relationships were found for ASBs with T2D, CVDs, and all-cause mortality and for SSBs with all-cause mortality. The findings from the current meta-analysis indicate that increased consumption of SSBs and ASBs is associated with the risk of T2D, CVDs, and all-cause mortality.


Assuntos
Bebidas Adoçadas Artificialmente/efeitos adversos , Doenças Cardiovasculares/complicações , Diabetes Mellitus Tipo 2/complicações , Açúcares/efeitos adversos , Doenças Cardiovasculares/mortalidade , Estudos de Coortes , Bases de Dados Factuais , Diabetes Mellitus Tipo 2/mortalidade , Humanos , Fatores de Risco , Bebidas Adoçadas com Açúcar , Edulcorantes
15.
J Colloid Interface Sci ; 603: 243-251, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34186401

RESUMO

Inadequate water-stability and antibacterial activity limit the biomedical application of polyvinyl alcohol (PVA)-based membranes in moist environments. In this work, we propose a strategy to improve the water-stability of PVA membranes via metal complexation and heat treatment. We report a simple routine where the zirconium-based UiO-66-NH2 metal-organic frameworks (MOFs) are nucleated as a layer on the surface of PVA nanofibrous membranes (UiO-66-NH2@PVA NFMs). We find that the chemical modification of membranes increases their hydrophilicity and adds on mechanical support for the brittle UiO-66-NH2 MOFs. Additionally, we demonstrate the application of UiO-66-NH2 MOFs as drug carriers for antibacterial drug, levofloxacin (LV). The active drug component is preloaded during the one-step nucleation process. The obtained LV loaded UiO-66-NH2@PVA NFMs (LV@UiO-66-NH2@PVA) are shown to be bactericidal with the efficiency > 99.9% at 100 µg/mL against two bacterial species, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Compared with the commercially available gauzes, the UiO-66-NH2@PVA and LV@UiO-66-NH2@PVA treatments will significantly improve the wound healing process. Animal studies show that the LV@UiO-66-NH2@PVA will effectively offer a safe alternative solution for the patients to protect against bacterial infections, demonstrating the potential application of MOF-based NFMs as wound dressing agents.


Assuntos
Estruturas Metalorgânicas , Nanofibras , Animais , Antibacterianos/farmacologia , Escherichia coli , Humanos , Álcool de Polivinil , Staphylococcus aureus , Água , Cicatrização , Zircônio
16.
Materials (Basel) ; 13(21)2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33114665

RESUMO

Electret melt-blown nonwovens are widely used for air purification due to their low pressure drop and high filtration efficiency. However, the charge stability could be affected by the ambient temperature and humidity, reducing the filtration efficiency, resulting in the electret melt blown filter not providing effective protection. Herein, we used corona charge to prepare electret melt-blown nonwovens and systematically studied the effects of different temperature and humidity on the structure, morphology, filtration performance, and surface potential within 24 h. The effect of treatment temperature and humidity on pressure drop was minimal because the fiber morphology and web structure of melt-blown nonwovens were not damaged. When the treatment temperature was lower than 70 °C, the effect on the filtration efficiency of the sample was small, but when the temperature increased to 90 or 110 °C, the filtration efficiency decreased significantly with the increase of the treatment time, and the surface potential also declined similarly. In conclusion, high temperatures will lead to charge escape and reduce the electrostatic adsorption effect. Furthermore, at the same temperature, increasing relative humidity can accelerate the charge release and make the filtration efficiency drop more. After the sample was treated at 110 °C and 90% relative humidity for 24 h, the filtration efficiency decreased from 95.49% to 38.16% at a flow rate of 14.16 cm s-1, and the surface potential dropped to the lowest value of -1.01 kV. This result shows that all links of electret melt-blown filter material from raw material to final use should be avoided in high temperature and high humidity conditions to ensure the protection effect.

17.
Nutrients ; 12(3)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197411

RESUMO

Hypertension is the most crucial single contributor to global burden of disease and mortality, while weight loss as a non-pharmacological strategy is recommended to reduce blood pressure. This study aims to examine the association between visceral adipose index (VAI) and hypertension in Chinese adults. Data were collected from the China Health and Nutrition Survey (CHNS), consisting of 8374 apparently healthy participants aged ≥18 years in the 2009 CHNS for cross-sectional analysis, and 4275 participants at entry from 2009 to 2011 for cohort analysis. Height, weight, waist circumference, blood pressure (BP), and blood lipid were measured. Information of population characteristics, smoking status, alcohol consumption, physical activity, and diet were determined by validated questionnaire. Higher VAI scores were significantly associated with higher BP levels and higher risk of hypertension after adjustment with potential confounders (all p-trend < 0.001). The adjusted hazard ratio of hypertension was 1.526 (95%CI: 1.194, 1.952; p-trend < 0.01) for participants in the highest quartile of VAI scores when compared with those in the lowest quartile after adjustment for age, physical activity, antihypertensive medication, total energy intake, salt intake, and other major lifestyle factors. VAI scores were significantly, longitudinally associated with hypertension development among apparently healthy Chinese adults.


Assuntos
Inquéritos Epidemiológicos , Hipertensão/complicações , Hipertensão/epidemiologia , Gordura Intra-Abdominal , Adulto , China/epidemiologia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino
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