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1.
Environ Sci Pollut Res Int ; 31(22): 32200-32211, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38644427

RESUMO

F-doped V2O5-WO3/TiO2 catalyst has been confirmed to have excellent denitration activity at low temperatures. Since the V2O5-WO3/TiO2 catalyst is a structure-sensitive catalyst, the loading order of V2O5 and WO3 may affect its denitration performance. In this paper, a series of F-doped V2O5-WO3/TiO2 catalysts with different V2O5 and WO3 loading orders were synthesized to investigate the effect of denitration performance at low temperatures. It was found that the loading orders led to significant gaps in denitration performance in the range of 120-240 °C. The results indicated loading WO3 first better utilized the oxygen vacancies on the TiF carrier promoting the generation of reduced vanadium species. In addition, loading WO3 first facilitated the dispersion of V2O5 thus enhanced the NH3 adsorption capacity of VWTiF. In situ DRIFT verified the rapid reaction between NO2, nitrate, and nitrite species and adsorbed NH3 over the VWTiF, confirming that the NH3 selective catalytic reduction (NH3-SCR) reaction over VWTiF at 240 °C proceeded by the Langmuir-Hinshelwood (L-H) mechanism. This research established the constitutive relationship between the loading order of V2O5 and WO3 and the denitration performance of the F-doped VWTi catalyst providing insights into the catalyst design process.


Assuntos
Titânio , Tungstênio , Vanádio , Tungstênio/química , Catálise , Titânio/química , Vanádio/química , Óxidos/química , Compostos de Vanádio/química , Adsorção
2.
BMC Public Health ; 24(1): 29, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166959

RESUMO

Being overweight and obese is associated with an elevated risk of developing noncommunicable diseases, which are the leading causes of mortality worldwide. It is a warning that global prevalence of overweight among university students ranges from 20 to 40%, which presents a significant public health problem. To date, there was no research conducted on medical students regarding the prevalence and associated factors of overweight and obesity in the countries of the Western Balkans (Slovenia, Croatia, Bosnia and Herzegovina, North Macedonia, and Serbia). The aim of this study was to determine the prevalence and potential demographic, socioeconomic, and health-related behavioral factors associated with overweight and obesity of medical students from Western Balkans. A cross-sectional study was conducted, surveying 2452 students from 14 medical faculties from 5 countries in the region. The prevalence of overweight was 12% and obesity was 2.3% among medical students from Western Balkans. Male gender and smoking status are significant positive predictors of overweight and obesity. Daily level of physical activity up to 1 h per day, going to preventive check-ups once a year or as a part of annual dormitory check-ups are associated with lower odds of being overweight and obese. By creating adequate public health educational programs, students can be influenced to acquire proper health-related lifestyle habits, which would lead to reducing the prevalence of overweight and obesity among the student population, as well as risk of developing noncommunicable diseases and improving the overall health of the population.


Assuntos
Doenças não Transmissíveis , Estudantes de Medicina , Masculino , Humanos , Sobrepeso/epidemiologia , Península Balcânica/epidemiologia , Prevalência , Estudos Transversais , Obesidade/epidemiologia , Índice de Massa Corporal
3.
Artigo em Inglês | MEDLINE | ID: mdl-38214820

RESUMO

Oral insulin (INS) is predicted to have the most therapeutic advantages in treating diabetes to repress hepatic glucose production through its potential to mimic the endogenous insulin pathway. Many oral insulin delivery systems have been investigated. Layered double hydroxide (LDH) as an inorganic material has been widely used in drug delivery thanks to its appealing features such as good biocompatibility, low toxicity, and excellent loading capability. However, when used in oral drug delivery, the effectiveness of LDH is limited due to the acidic degradation in the stomach. In this study, to overcome these challenges, chitosan (Chi) and alginate (Alg) dual-coated LDH nanocomposites with the loading of insulin (Alg-Chi-LDH@INS) were developed by the layered-by-layered method for oral insulin delivery with dynamic size of ~ 350.8 nm, negative charge of ~ - 13.0 mV, and dispersity index 0.228. The insulin release profile was evaluated by ultraviolet-visible spectroscopy. The drug release profiles evidenced that alginate and chitosan coating partially protect insulin release from a burst release in acidic conditions. The analysis using flow cytometry showed that chitosan coating significantly enhanced the uptake of LDH@INS by Caco-2 cells compared to unmodified LDH and free insulin. Further in the in vivo study in streptozocin-induced diabetic mice, a significant hypoglycemic effect was maintained following oral administration with great biocompatibility (~ 50% blood glucose level reduction at 4 h). This research has thus provided a potential nanocomposite system for oral delivery of insulin.

4.
Chem Biol Interact ; 383: 110676, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37586544

RESUMO

Solanesol is a tetra sesquiterpene enol with various biological activities. Modern medical studies have confirmed that solanesol has the function of lipid antioxidation and scavenges free radicals. This study aimed to investigate the protective effect of solanesol against oxidative damage induced by high glucose on human normal hepatocytes (L-02 cells) and its possible mechanism. The results showed that solanesol could effectively improve the decrease of cell viability induced by high glucose, decrease the contents of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) in the extracellular medium, increased the enzyme activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), balanced the level of reactive oxygen species (ROS) in cells, inhibited lipid peroxidation of all kinds of biological membranes, and restored mitochondrial membrane potential (MMP). In addition, Solanesol also inhibited the expression of Keap1, promoted the nuclear translocation of Nrf2 by hydrogen bonding with Nrf2, and activated the expression of downstream antioxidant factors NQO1 and HO-1. Altogether, these findings suggest that solanesol may be a potential protectant against diabetic liver injury.


Assuntos
Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Hepatócitos , Antioxidantes/farmacologia , Antioxidantes/metabolismo
5.
Int Immunopharmacol ; 123: 110779, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37582313

RESUMO

Skin wound healing is a multifaceted and intricate process involving inflammation, tissue proliferation, and scar formation, all of which are accompanied by the continuous application of mechanical forces. Mechanotransduction is the mechanism by which the skin receives and reacts to physical signals from the internal and external environment, converting them into intracellular biochemical signals. This intricate process relies on specialized proteins known as mechanotransducers, with Piezo1 being a critical mechanosensitive ion channel that plays a central role in this process. This article provides an overview of the structural characteristics of Piezo1 and summarizes its effects on corresponding cells or tissues at different stages of skin trauma, including how it regulates skin sensation and skin-related diseases. The aim is to reveal the potential diagnostic and therapeutic value of Piezo1 in skin trauma and skin-related diseases. Piezo1 has been reported to be a vital mediator of mechanosensation and transduction in various organs and tissues. Given its high expression in the skin, Piezo1, as a significant cell membrane ion channel, is essential in activating intracellular signaling cascades that trigger several cellular physiological functions, including cell migration and muscle contraction. These functions contribute to the regulation and improvement of wound healing.


Assuntos
Canais Iônicos , Mecanotransdução Celular , Membrana Celular/metabolismo , Movimento Celular , Mecanotransdução Celular/fisiologia , Transdução de Sinais , Humanos
6.
Biochem Pharmacol ; 215: 115736, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37549795

RESUMO

In the past, neuropeptide substance P (SP) was predominantly recognized as a neuroinflammatory factor, while its potent healing activity was overlooked. This paper aims to review the regulatory characteristics of neuropeptide SP in both normal and diabetic wound healing. SP actively in the regulation of wound healing-related cells directly and indirectly, exhibiting robust inflammatory properties, promoting cell proliferation and migration and restoring the activity and paracrine ability of skin cells under diabetic conditions. Furthermore, SP not only regulates healing-related cells but also orchestrates the immune environment, thereby presenting unique and promising application prospects in wound intervention. As new SP-based preparations are being explored, SP-related drugs are poised to become an effective therapeutic intervention for diabetic foot ulcers (DFU).


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/tratamento farmacológico , Substância P/farmacologia , Substância P/uso terapêutico , Cicatrização , Pele , Proliferação de Células
7.
Bone Res ; 11(1): 42, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542028

RESUMO

Low back pain (LBP) is the world's leading cause of disability and is increasing in prevalence more rapidly than any other pain condition. Intervertebral disc (IVD) degeneration and facet joint osteoarthritis (FJOA) are two common causes of LBP, and both occur more frequently in elderly women than in other populations. Moreover, osteoarthritis (OA) and OA pain, regardless of the joint, are experienced by up to twice as many women as men, and this difference is amplified during menopause. Changes in estrogen may be an important contributor to these pain states. Receptors for estrogen have been found within IVD tissue and nearby joints, highlighting the potential roles of estrogen within and surrounding the IVDs and joints. In addition, estrogen supplementation has been shown to be effective at ameliorating IVD degeneration and OA progression, indicating its potential use as a therapeutic agent for people with LBP and OA pain. This review comprehensively examines the relationship between estrogen and these pain conditions by summarizing recent preclinical and clinical findings. The potential molecular mechanisms by which estrogen may relieve LBP associated with IVD degeneration and FJOA and OA pain are discussed.

8.
Drug Discov Today ; 28(1): 103393, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36208724

RESUMO

Currently, the only practical way to treat type 1 and advanced insulin-dependent type 2 diabetes mellitus (T1/2DM) is the frequent subcutaneous injection of insulin, which is significantly different physiologically from endogenous insulin secretion from pancreatic islets and can lead to hyperinsulinemia, pain, and infection in patients with poor compliance. Hence, oral insulin delivery has been actively pursued to revolutionize the treatment of insulin-dependent diabetes. In this review, we provide an overview of recent progress in developing poly(lactic co-glycolic acid) (PLGA) nanoparticles (NPs) for oral insulin delivery. Different strategies for insulin-loaded PLGA NPs to achieve normoglycemic effects are discussed. Finally, challenges and future perspectives of PLGA NPs for oral insulin delivery are put forward.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Nanopartículas , Animais , Humanos , Insulina/uso terapêutico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/uso terapêutico , Portadores de Fármacos , Ácido Poliglicólico/uso terapêutico , Ácido Láctico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Experimental/tratamento farmacológico
9.
Artigo em Inglês | MEDLINE | ID: mdl-36498317

RESUMO

Regular physical activity (PA) has multiple beneficial effects on students' health, effectively reducing the risk of various non-communicable diseases. Various factors play a role in an individual's motivation to engage in and maintain regular PA. So far, no research dealing with the motives and barriers for regular PA among medical students has been conducted in the countries of the Western Balkans. The aim of this study was to identify the motives and barriers related to regular PA and compare them with different demographic, socioeconomic, and individual lifestyle factors among Western Balkans medical students. The research was conducted in a form of a cross-sectional study. It included 2452 medical students from 14 faculties in five countries (Slovenia, Croatia, Bosnia and Herzegovina, North Macedonia, and Serbia). The most commonly reported motive of medical students for regular PA is to feel better, followed by stress reduction, to look better, the desire to lose weight, and to control chronic disease. PA improvement motives are more frequently associated with the female gender, more advanced years of study, a normal weight, above average household income, and a non-smoking status. Faculty obligations are the most common barrier for regular PA among medical students, followed by other barriers, such as financial situation, current life situation, and health conditions. Barriers are more frequently reported by male students who are overweight or obese, who have a below average income, and are smokers. It is necessary for public health authorities to examine and take into account the perceived motives and barriers when forming activities and policies that aim at increasing the level of PA, in order to enhance the health of the student population.


Assuntos
Estudantes de Medicina , Humanos , Masculino , Feminino , Estudos Transversais , Exercício Físico , Motivação , Sérvia
10.
Int J Biol Macromol ; 209(Pt A): 83-92, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35351550

RESUMO

As a soybean oil extractive byproduct, high temperature defatted soy meal (HSM) presents great potential as a raw material for vegetable protein adhesives to replace aldehyde-based adhesives in the wood-based panel production. However, the application has been hindered by its poor cold-pressing adhesive performance. Herein, a novel HSM-based adhesive with excellent cold-pressing adhesion performance was developed based on mussel-inspired cation-π interactions. Highly reactive polyamidoamine-epichlorohydrin (PAE) and folic acid (FA) were added into an HSM-based adhesive to construct a dual-network system stabilized by strong cation-π interactions. The coacervate formed by PAE and FA served as an "internal adhesive" to bond HSM particles together, yielding high initial viscosity but easy sizing. As expected, the prepared adhesive exhibited an excellent cold-pressing bonding strength of 423 kPa, showing a 295% improvement compared to the soy protein (SP) adhesive. To improve the hot-pressing bonding strength of the adhesives, inorganic calcium carbonate (CaCO3) particles were introduced into the adhesive system to build an organic-inorganic hybrid adhesive system. The wet shear strength of the SPAE-FA-CaCO3 adhesive significantly improved from 0.63 MPa to 0.96 MPa, meeting the requirements for the practical application. This method provides a novel strategy to exploit high-performance vegetable protein-based wood adhesives.


Assuntos
Adesivos , Madeira , Adesivos/química , Cátions , Óleo de Soja , Proteínas de Soja/química , Madeira/química
11.
ACS Appl Mater Interfaces ; 13(49): 59527-59537, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34846859

RESUMO

Soy protein (SP) adhesives can resolve several problems with aldehyde-based adhesives, including formaldehyde release and excessive dependence on petroleum-based materials. Nevertheless, their development is hindered by the lack of balance between fluidity and high cold-pressing adhesive strength. A dynamically cross-linked SP adhesive with excellent fluidity and cold-pressing adhesion was developed in this study based on the polyphenol-metal ion redox-induced gelation system. SP was blended with acrylamide (AM), ammonium persulfate (APS), and the tannic acid (TA)-Fe3+ complex to prepare an adhesive gel precursor with good fluidity. In situ gelation of SP adhesive was then achieved via AM polymerization, as initiated by redox between TA and Fe3+. As expected, the prepared adhesive gel exhibited outstanding cold-pressing bonding strength (650 kPa) to the veneers compared to the neat SP adhesive, which has almost no cold-pressing bonding strength to the veneers. The TA-Fe3+ complex induced an in situ gelation system, which endowed the SP adhesive with strong cohesion; the topological entanglement of the adhesive gel in the veneers contributed to tight interfacial combinations. The TA-Fe3+ complex served not only as an accelerator of SP adhesive gelation but also as a "cross-linking core" for the cross-link SP adhesive system. The prepared SP-based adhesive also exhibited outstanding hot-pressing bonding strength and mildew resistance. The proposed polyphenol-metal ion-induced in situ gelation strategy may provide a new approach for developing advanced vegetable protein adhesives to replace aldehyde adhesives.


Assuntos
Materiais Biocompatíveis/química , Temperatura Baixa , Compostos Férricos/química , Polifenóis/química , Proteínas de Soja/química , Adesivos , Géis/química , Íons/química , Teste de Materiais , Fluidez de Membrana , Oxirredução , Tamanho da Partícula , Taninos/química
12.
ACS Appl Mater Interfaces ; 13(32): 38732-38744, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34369140

RESUMO

Soy protein (SP)-based adhesives can replace traditional aldehyde-based adhesives for the manufacturing of wood-based panels. However, developing a SP-based adhesive with excellent prepressing bonding strength, flame retardancy, and mildew resistance remains a challenge. Herein, an inorganic crystal cross-linked hybrid SP adhesive was developed inspired by the "secreting-hardening" process of the mussel adhesive protein and the organic-inorganic hybrid adhesive system of the oyster. Calcium sulfoaluminate (CSA) was introduced into the adhesive mixture of SP and acrylic acid to induce the in situ polymerization of acrylic acid to achieve adhesive gelation. The generation of the inorganic crystals by hydration of CSA not only contributed to the formation of a stable cross-linked hybrid adhesive system for strong cohesion but also provided strong interfacial adhesion between the adhesive layers and the plywood veneers. As anticipated, the prepared plywood sample bonded with the hybrid adhesive gel had an excellent prepressing bonding strength of 544 kPa, representing a significant increase compared to that of the pure SP adhesive (19 kPa). Moreover, the generated inorganic crystals endowed the adhesive with excellent mildew resistance and flame retardancy. This study provides a novel and effective strategy for the preparation of high-performance SP-based adhesives.


Assuntos
Adesivos/química , Compostos de Alumínio/química , Compostos de Cálcio/química , Ostreidae/metabolismo , Proteínas/química , Proteínas de Soja/química , Compostos de Enxofre/química , Animais
13.
J Mater Chem B ; 9(20): 4230-4240, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33998631

RESUMO

Multifunctional hydrogels that integrate stretchability, adhesion, self-healing, and antibacterial properties may find use in a variety of fields including electronic skin, wound dressings, and wearable devices; however, traditional hydrogels often exhibit short-term adhesiveness, poor mechanical properties, and a lack of antibacterial activity. Herein, a plant-inspired polyacrylamide-soybean protein isolate-pyrogallol/borax (PAM-SPI-P/B) hydrogel has been developed using a facile green method based on dynamic coordination cross-linking between pyrogallol (PG) and borax. The PG-borax dynamic bonds adjusted the network structure of the hydrogels to provide greater structural integrity to the PAM-SPI double network. This hydrogel possessed a high mechanical strength (large elongation up to 760% and compressive strength up to 1.25 MPa at 80% strain), low swelling ratio, and self-healing properties. Inspired by natural polyphenols that contain adhesive molecules, the addition of pyrogallol provided the hydrogel excellent adhesion to various hydrophilic and hydrophobic substrates. And with the inhibition of pyrogallol autoxidation due to the borax protection, the hydrogel showed repeatable and durable adhesion over 20 cycles. The obtained hydrogels also exhibited good antibacterial activities against Escherichia coli and Staphylococcus aureus because they were based on pyrogallol and borax, which have antibacterial properties. Accordingly, we envision that the PAM-SPI-P/B hydrogels have great potential for use in biomimetic tissues and biosensors.


Assuntos
Antibacterianos/farmacologia , Boratos/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , Hidrogéis/farmacologia , Pirogalol/farmacologia , Adesinas Bacterianas/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Boratos/química , Reagentes de Ligações Cruzadas/síntese química , Reagentes de Ligações Cruzadas/química , Escherichia coli/efeitos dos fármacos , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirogalol/química , Staphylococcus aureus/efeitos dos fármacos
14.
J Hazard Mater ; 415: 125612, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-33730646

RESUMO

Heavy metal ions can cause a series of hazards to environment and humans. Herein, we developed a wood-inspired nanocellulose aerogel adsorbent with excellent selective capability, superfast adsorption, and easy regeneration. The premise for the design is that the biomimetic honeycomb architecture and specific covalent bonding networks can provide the adsorbent with structural and mechanical integrity yet superfast removal of target contaminants. The as-obtained adsorbent showed the maximum adsorption capacity for Pb(II), Cu(II), Zn(II), Cd(II), and Mn(II) of 571 mg g-1, 462 mg g-1, 361 mg g-1, 263 mg g-1, and 208 mg g-1, respectively. The adsorbent could remove Pb(II) species with super-rapid speed (87% and 100% of its equilibrium uptake in 2 min and 10 min, respectively). Furthermore, the adsorption isotherm and kinetics models were in accord with the Langmuir and pseudo-second-order models, indicating that the adsorption behavior was dominated by monolayer chemisorption. The aerogel adsorbent had better affinity for Pb(II) than other coexisting ions in wastewater and could be regenerated for at least five cycles. Such a wood-inspired aerogel adsorbent holds great potential in the application of contaminant cleaning.

15.
Polymers (Basel) ; 11(10)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547025

RESUMO

It remains a great challenge to fabricate bio-based soy protein isolate (SPI) composite film with both favorable water resistance and excellent mechanical performance. In this study, waterborne epoxy emulsions (WEU), which are low-cost epoxy crosslinkers, together with mussel-inspired dopamine-decorated silk fiber (PSF), were used to synergistically improve the water resistance and mechanical properties of SPI-based film. A stable crosslinking network was generated in SPI-based films via multiple physical and chemical combinations of WEU, PSF, and soy protein matrixes, and was confirmed by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), and solid state 13C nuclear magnetic resonance (13C NMR). As expected, remarkable improvement in both water resistance and Young's modulus (up to 370%) was simultaneously achieved in SPI-based film. The fabricated SPI-based film also exhibited favorable thermostability. This study could provide a simple and environmentally friendly approach to fabricate high-performance SPI-based film composites in food packaging, food preservation, and additive carrier fields.

16.
Polymers (Basel) ; 11(6)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163610

RESUMO

Soybean meal-based adhesives are attractive potential environmentally friendly replacements for formaldehyde-based adhesives. However, the low strength and poor water resistance of soybean meal-based adhesives limit their practical application. This study was conducted to develop a natural fiber-reinforced soybean meal-based adhesive with enhanced water resistance and bonding strength. Pulp fiber (PF), poplar wood fiber (WF), and bagasse fiber (BF) were added as fillers into the soybean meal-based adhesive to enhance its performance via hydrogen bonding between the PF and the soybean meal system. The enhanced adhesive exhibited a strong crosslinking structure characterized by multi-interfacial interactions wherein PF served as a bridging ligament and released residual stress into the crosslinking network. The crosslinked structure and improved interfacial interactions were confirmed by Fourier transform infrared (FTIR) spectrophotometry, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) measurements. Plywood bonded with 4 wt % PF-containing soybean meal-based adhesive exhibited a wet shear strength (1.14 MPa) exceeding that of plywood bonded with the control group by 75.4% due to the stable crosslinking network having efficiently transformed stress and prevented the permeation of water molecules.

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