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1.
Crit Rev Food Sci Nutr ; 63(28): 9098-9110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35507474

RESUMO

Antibiotic contamination is becoming a prominent global issue. Therefore, sensitive, specific and simple technology is desirable the demand for antibiotics detection. Biosensors based on split aptamer has gradually attracted extensive attention for antibiotic detection due to its higher sensitivity, lower cost, false positive/negative avoidance and flexibility in sensor design. Although many of the reported split aptamers are antibiotics aptamers, the acquisition and mechanism of splitting is still unknow. In this review, six reported split aptamers in antibiotics are outlined, including Enrofloxacin, Kanamycin, Tetracycline, Tobramycin, Neomycin, Streptomycin, which have contributed to promote interest, awareness and thoughts into this emerging research field. The study introduced the pros and cons of split aptamers, summarized the assembly principle of split aptamer and discussed the intermolecular binding of antibiotic-aptamer complexes. In addition, the recent application of split aptamers in antibiotic detection are introduced. Split aptamers have a promising future in the design and development of biosensors for antibiotic detection in food and other field. The development of the antibiotic split aptamer meets many challenges including mechanism discovery, stability improvement and new biosensor development. It is believed that split aptamer could be a powerful molecular probe and plays an important role in aptamer biosensor.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Antibacterianos , Aptâmeros de Nucleotídeos/química , Sondas Moleculares
2.
Molecules ; 28(12)2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37375396

RESUMO

Ochratoxin A (OTA) is the most common mycotoxin and can be found in wheat, corn and other grain products. As OTA pollution in these grain products is gaining prominence as a global issue, the demand to develop OTA detection technology has attracted increasing attention. Recently, a variety of label-free fluorescence biosensors based on aptamer have been established. However, the binding mechanisms of some aptasensors are still unclear. Herein, a label-free fluorescent aptasensor employing Thioflavin T (ThT) as donor for OTA detection was constructed based on the G-quadruplex aptamer of the OTA aptamer itself. The key binding region of aptamer was revealed by using molecular docking technology. In the absence of the OTA target, ThT fluorescent dye binds with the OTA aptamer to form an aptamer/ThT complex, and results in the fluorescence intensity being obviously enhanced. In the presence of OTA, the OTA aptamer binds to OTA because of its high affinity and specificity to form an aptamer/OTA complex, and the ThT fluorescent dye is released from the OTA aptamer into the solution. Therefore, the fluorescence intensity is significantly decreased. Molecular docking results revealed that OTA is binding to the pocket-like structure and surrounded by the A29-T3 base pair and C4, T30, G6 and G7 of the aptamer. Meanwhile, this aptasensor shows good selectivity, sensitivity and an excellent recovery rate of the wheat flour spiked experiment.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Ocratoxinas , Corantes Fluorescentes/química , Simulação de Acoplamento Molecular , Farinha , Aptâmeros de Nucleotídeos/química , Triticum , Ocratoxinas/análise , Técnicas Biossensoriais/métodos , Limite de Detecção
3.
Bioprocess Biosyst Eng ; 45(10): 1693-1703, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36029348

RESUMO

In this study, a single-component high-yielding Micromonospora echinospora strain 49-92S-KL01 was constructed by deleting methyltransferase-encoding genes genK and genL. In 5-L fermentation trials, gentamicin C1a titers in the mutant strain were 3.22-fold higher than that in the parental strain (211 U/mL vs. 50 U/mL). The glycolysis pathway and tricarboxylic acid cycle fluxes were reduced by 26.8% and 26.6%, respectively, compared to the parental strain according to the metabolic flux analysis during the stationary phase, resulting in lower levels of energy supplements required for the cellular maintenance. Meanwhile, a significant enhancement in precursor (paromamine) accumulation and availability was observed in 49-92S-KL01 compared to parental strain. These results indicate that genK and genL significantly affect the synthesis of gentamicin C1a. In addition, this study provides a more rational strategy for gentamicin C1a production.


Assuntos
Micromonospora , Fermentação , Gentamicinas/metabolismo , Gentamicinas/farmacologia , Metiltransferases/genética , Micromonospora/genética , Micromonospora/metabolismo
4.
Behav Brain Funct ; 11: 6, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25888780

RESUMO

BACKGROUND: Aluminum overload can cause severe brain injury and neurodegeneration. Previous studies suggest that prostacyclin synthase (PGIS) expression and prostacyclin receptor (IP) activation are beneficial for treatment of acute traumatic and ischemic brain injury. However, the potential value of PGIS/IP signaling pathway to chronic brain injury is still unclear. In this study, we investigated the change of PGIS/IP signaling pathway and the effect of beraprost sodium (BPS) on chronic brain injury in chronic aluminum-overload rats. METHODS: Rat model of chronic cerebral injury was established by chronic intragastric administration of aluminum gluconate(Al3+ 200 mg/kg per day,5d a week for 20 weeks). The methods of ELISA, qRT-PCR and Western blotting were used to detect the PGI2 level and the PGIS and IP mRNA and protein levels in hippocampi of chronic aluminum-overload rats, respectively. Rat hippocampal superoxide dismutase (SOD) activity and malondialdehyde (MDA) content also were measured. The effects of BPS (6, 12 and 24 µg⋅kg(-1)) on brain injury in chronic aluminum-overload rats were evaluated. RESULTS: Compared with the control group, PGIS mRNA expression, PGI2 level, and the IP mRNA and protein expressions significantly increased in hippocampi of chronic aluminum-overload rats. Administration of BPS significantly improved spatial learning and memory function impairment and hippocampal neuron injury induced by chronic aluminum overload in rats. Meanwhile, administration of BPS resulted in a decrease of PGI2 level and downregulation of PGIS and IP expressions in a dose-dependent manner. Aluminum overload also caused a decrease of SOD activity and an increase of MDA content. Administration of BPS significantly blunted the decrease of SOD activity and the increase of MDA content induced by aluminum overload in rats. CONCLUSIONS: BPS has a significant neuroprotective effect on chronic brain injury induced by aluminum overload in rats. Remodeling the balance of PGIS/IP signaling pathway and inhibition of oxidative stress involve in the neuroprotective mechanism of BPS in aluminum-overload rats. The PGIS/IP signaling pathway is a potential therapeutic strategy for chronic brain injury patients.


Assuntos
Compostos de Alumínio , Anti-Inflamatórios não Esteroides/uso terapêutico , Dano Encefálico Crônico/induzido quimicamente , Dano Encefálico Crônico/prevenção & controle , Epoprostenol/análogos & derivados , Fármacos Neuroprotetores/uso terapêutico , Alumínio/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Epoprostenol/biossíntese , Epoprostenol/uso terapêutico , Gluconatos , Hipocampo/metabolismo , Hipocampo/patologia , Oxirredutases Intramoleculares/metabolismo , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/prevenção & controle , Transtornos da Memória/psicologia , Proteínas do Tecido Nervoso/biossíntese , Ratos , Ratos Sprague-Dawley , Receptores de Epoprostenol/efeitos dos fármacos , Superóxido Dismutase/metabolismo
5.
Behav Brain Funct ; 11: 8, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25888969

RESUMO

BACKGROUND: Acute and chronic brain damages including neurodegenerative diseases are a group of neuroinflammation-associated diseases characterized by cognitive function defect and progressive neuron loss. The pathophysiological procession of brain damages involves the overexpression of cyclooxygenase (COX)-2. Owing to the limited benefit to chronic brain damage and the late adverse effect of COX-2 inhibitors, the COX downstream signaling pathway has become a focus in neurological research. In order to explore the mechanism of aluminum neurotoxicity and the importance of COX2 downstream signaling pathways to chronic brain damage, the present study was designed to simultaneously observe the prostaglandin (PG) contents, and the expressions of PG synthases and PG receptors of hippocampus in a rat model induced by chronic administration of aluminium gluconate. METHODS: A rat model of chronic brain damage was established by chronic intragastric administration of aluminium gluconate (Al3+ 200 mg/kg per day, 5d a week for 20 weeks). PG contents, the expressions of PG synthases, and the expressions of PG receptors in rats were measured by ELISA, RT-PCR and Western blotting, respectively. RESULTS: Chronic aluminium gluconate administration resulted in hippocampal neuron injury and learning and memory disorders in rats. Aluminium gluconate administration also resulted in increased levels of PGE2, PGD2, TXA2, PGI2, and PGF2α in rat hippocampus. The DP1, EP2, IP, mPGES-1, EP4, PGIS and TXAS mRNA expressions, and the DP1, EP2 and IP protein expressions significantly increased in the Al-treated hippocampus, while the EP3 and FP mRNA and protein expressions and the TP mRNA expression decreased. CONCLUSIONS: The PGS/PGs/PG receptors signaling pathway in chronic aluminium gluconate-overloaded rat hippocampus is disturbed, which may be involved in the mechanism of aluminium neurotoxicity.


Assuntos
Compostos de Alumínio , Dano Encefálico Crônico/induzido quimicamente , Dano Encefálico Crônico/fisiopatologia , Ciclo-Oxigenase 2 , Hipocampo/enzimologia , Hipocampo/patologia , Síndromes Neurotóxicas/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Animais , Gluconatos , Intubação Gastrointestinal , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/fisiologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Prostaglandinas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Prostaglandina/biossíntese , Receptores de Prostaglandina/genética , Superóxido Dismutase/metabolismo
6.
Biomed Pharmacother ; 175: 116645, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729050

RESUMO

Peripheral nerve injuries (PNIs) frequently occur due to various factors, including mechanical trauma such as accidents or tool-related incidents, as well as complications arising from diseases like tumor resection. These injuries frequently result in persistent numbness, impaired motor and sensory functions, neuropathic pain, or even paralysis, which can impose a significant financial burden on patients due to outcomes that often fall short of expectations. The most frequently employed clinical treatment for PNIs involves either direct sutures of the severed ends or bridging the proximal and distal stumps using autologous nerve grafts. However, autologous nerve transplantation may result in sensory and motor functional loss at the donor site, as well as neuroma formation and scarring. Transplantation of Schwann cells/Schwann cell-like cells has emerged as a promising cellular therapy to reconstruct the microenvironment and facilitate peripheral nerve regeneration. In this review, we summarize the role of Schwann cells and recent advances in Schwann cell therapy in peripheral nerve regeneration. We summarize current techniques used in cell therapy, including cell injection, 3D-printed scaffolds for cell delivery, cell encapsulation techniques, as well as the cell types employed in experiments, experimental models, and research findings. At the end of the paper, we summarize the challenges and advantages of various cells (including ESCs, iPSCs, and BMSCs) in clinical cell therapy. Our goal is to provide the theoretical and experimental basis for future treatments targeting peripheral nerves, highlighting the potential of cell therapy and tissue engineering as invaluable resources for promoting nerve regeneration.


Assuntos
Regeneração Nervosa , Traumatismos dos Nervos Periféricos , Células de Schwann , Células de Schwann/fisiologia , Humanos , Animais , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/terapia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Nervos Periféricos/fisiologia
7.
Food Res Int ; 165: 112567, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869555

RESUMO

Globally, inflammation and metabolic disorders pose serious public health problems and are major health concerns. It has been shown that natural polyphenols are effective in the treatment of metabolic diseases, including anti-inflammation, anti-diabetes, anti-obesity, neuron-protection, and cardio-protection. NLRP3 inflammasome, which are multiprotein complexes located within the cytosol, play an important role in the innate immune system. However, aberrant activation of the NLRP3 inflammasome were discovered as essential molecular mechanisms in triggering inflammatory processes as well as implicating it in several major metabolic diseases, such as type 2 diabetes mellitus, obesity, atherosclerosis or cardiovascular disease. Recent studies indicate that natural polyphenols can inhibit NLRP3 inflammasome activation. In this review, the progress of natural polyphenols preventing inflammation and metabolic disorders via targeting NLRP3 inflammasome is systemically summarized. From the viewpoint of interfering NLRP3 inflammasome activation, the health effects of natural polyphenols are explained. Recent advances in other beneficial effects, clinical trials, and nano-delivery systems for targeting NLRP3 inflammasome are also reviewed. NLRP3 inflammasome is targeted by natural polyphenols to exert multiple health effects, which broadens the understanding of polyphenol mechanisms and provides valuable guidance to new researchers in this field.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 2 , Humanos , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Inflamação , Obesidade , Polifenóis
8.
Food Chem Toxicol ; 178: 113943, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37451596

RESUMO

Perfluorodecanoic acid (PFDA), a chemical contaminant, may casue became obesity, which makes it a public health concern. In this study, we investigated the effects of PFDA on adiposity development and hepatic lipid accumulation in mice fed with a high-fat diet (HFD). Animals were assigned to two diet treatments (low-fat and high-fat); and PFDA was administered through drinking water for 12 weeks. The contaminant promoted body weight gain and adiposity in HFD-fed mice. Moreover, HFD-fed mice exposed to PFDA had impaired glucose metabolism, inflammation and hepatic lipid accumulation compared to mice fed HFD alone. PFDA activated the expression of hepatic NLRP3 and caspase-1, and induced that of SREBP-1c expression in the liver of HFD-fed mice. PFDA exposure in HFD-fed mice significantly inhibited hepatic AMPK expression than animals fed HFD without PFDA exposure. Furthermore, MCC950, an NLRP3 inhibitor, suppressed the upregulation of NLRP3 and caspase-1 expression, and inhibited the expression of SREBP-1c and the accumulation of hepatic lipid in mice exposed to PFDA. Thus, PFDA may enhance HFD-induced adiposity and hepatic lipid accumulation through the NLRP3/caspase-1 pathway. This contaminant may be a key risk factor for obesity development in individuals consuming high-fat foods, particularly Western diet.


Assuntos
Adiposidade , Proteína 3 que Contém Domínio de Pirina da Família NLR , Masculino , Camundongos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Dieta Hiperlipídica/efeitos adversos , Caspase 1/metabolismo , Camundongos Endogâmicos C57BL , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Metabolismo dos Lipídeos , Fígado , Obesidade/induzido quimicamente , Obesidade/metabolismo , Ácidos Decanoicos
9.
J Agric Food Chem ; 71(25): 9609-9627, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37316469

RESUMO

Sarcopenia is prevalent among the older population and severely affects human health. Tea catechins may benefit for skeletal muscle performance and protect against secondary sarcopenia. However, the mechanisms underlying their antisarcopenic effect are still not fully understood. Despite initial successes in animal and early clinical trials regarding the safety and efficacy of (-)-epigallocatechin-3-gallate (EGCG), a major catechin of green tea, many challenges, problems, and unanswered questions remain. In this comprehensive review, we discuss the potential role and underlying mechanisms of EGCG in sarcopenia prevention and management. We thoroughly review the general biological activities and general effects of EGCG on skeletal muscle performance, EGCG's antisarcopenic mechanisms, and recent clinical evidence of the aforesaid effects and mechanisms. We also address safety issues and provide directions for future studies. The possible concerted actions of EGCG indicate the need for further studies on sarcopenia prevention and management in humans.


Assuntos
Catequina , Sarcopenia , Animais , Humanos , Polifenóis/farmacologia , Chá , Catequina/farmacologia , Sarcopenia/tratamento farmacológico , Sarcopenia/prevenção & controle
10.
Food Chem X ; 17: 100539, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36845513

RESUMO

The long-term storage of rice will inevitably be involved in the deterioration of edible quality, and aged rice poses a great threat to food safety and human health. The acid value can be employed as a sensitive index for the determination of rice quality and freshness. In this study, near-infrared spectra of three kinds of rice (Chinese Daohuaxiang, southern japonica rice, and late japonica rice) mixed with different proportions of aged rice were collected. The partial least squares regression (PLSR) model with different preprocessing was constructed to identify the aged rice adulteration. Meanwhile, a competitive adaptive reweighted sampling (CARS) algorithm was used to extract the optimization model of characteristic variables. The constructed CARS-PLSR model method could not only reduce greatly the number of characteristic variables required by the spectrum but also improve the identification accuracy of three kinds of aged-rice adulteration. As above, this study proposed a rapid, simple, and accurate detection method for aged-rice adulteration, providing new clues and alternatives for the quality control of commercial rice.

11.
Food Chem Toxicol ; 171: 113520, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36423729

RESUMO

Perfluorodecanoic acid (PFDA) is a toxic persistent pollutant that is extensively used in food applications, such as food packaging and cookware. Emerging evidence indicates that PFDA exposure were associated with higher plasma triglyceride concentration in human. In contrast, it is unknown how PFDA might affect adipogenesis. To explore the effects and underlying mechanisms of PFDA on lipid metabolism in this study, both HepG2 cells and 3T3-L1 differentiation model were used. The results showed that PFDA promoted the cellular triglyceride accumulation and triglyceride content in concentration-dependent manners. Furthermore, PFDA activated the NLRP3 inflammasome, which is crucial for the induction of lipogenic genes expression including fatty acid synthase (FAS), hydroxymethylglutaryl coenzyme A synthase (HMGCS), and stearoyl-CoA desaturase 1 (SCD1). Additionally, PFDA-induced adipogenesis was abolished by caspase-1 inhibitor and siNLRP3 in HepG2 cells. Moreover, after PFDA treatment, the expression of SREBP1, an important regulator of lipid metabolism, was increased, as well as its target genes, and PFDA-induced SREBP1 enhanced expression can be abolished by caspase-1 inhibitor and siNLRP3 as well. Together, these results provide to understanding of the potential health implications of exposure to PFDA on lipid accumulation, and suggest that PFDA can promote adipogenesis via an NLRP3 inflammasome-mediated SREBP1 pathway.


Assuntos
Adipogenia , Inflamassomos , Camundongos , Animais , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Células 3T3-L1 , Metabolismo dos Lipídeos , Triglicerídeos
12.
Foods ; 13(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38201045

RESUMO

In this study, the conditions for optimizing the determination of succinic semialdehyde dehydrogenase (SSADH, EC 1.2.1.79) activity in germinated Tartary buckwheat were investigated. Based on a single-factor test, the effects of temperature, pH, and succinic semialdehyde (SSA) concentration on the enzyme activity of germinated buckwheat SSADH were investigated by using the response surface method, and optimal conditions were used to study the enzymatic properties of germinated buckwheat SSADH. The results revealed that the optimum conditions for determining SSADH enzyme activity are as follows: temperature-30.8 °C, pH-8.7, and SSA concentration-0.3 mmol/L. Under these conditions, SSADH enzyme activity was measured as 346 ± 9.61 nmol/min. Furthermore, the thermal stability of SSADH was found to be superior at 25 °C, and its pH stability remained comparable at pH levels of 7.6, 8.1, and 8.6 in germinated Tartary buckwheat samples; however, a decline in stability was observed at pH 9.1. Cu2+, Co2+, and Ni2+ exhibited an activating effect on SSADH activity in germinating Tartary buckwheat, with Cu2+ having the greatest influence (p < 0.05), which was 1.21 times higher than that of the control group. Zn2+, Mn2+, and Na+ inhibited SSADH activity in germinating Tartary buckwheat, with Zn2+ showing the strongest inhibitory effect (p < 0.05). On the other hand, the Km and Vmax of SSADH for SSA in germinated Tartary buckwheat were 0.24 mmol/L and 583.24 nmol/min. The Km and Vmax of SSADH for NAD+ in germinated Tartary buckwheat were 0.64 mmol/L and 454.55 nmol/min.

13.
Front Nutr ; 9: 836112, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35284456

RESUMO

The beneficial effects of green tea polyphenols (GTPs) on D-galactose (D-Gal)-induced liver aging in male Kunming mice were investigated. For this purpose, 40 adult male Kunming mice were divided into four groups. All animals, except for the normal control and GTPs control, were intraperitoneally injected with D-galactose (D-Gal; 300 mg/kg/day for 5 days a week) for 12 consecutive weeks, and the D-Gal-treated mice were allowed free access to 0.05% GTPs (w/w) diet or normal diet for 12 consecutive weeks. Results showed that GTP administration improved the liver index and decreased transaminases and total bilirubin levels. Furthermore, GTPs significantly increased hepatic glutathione and total antioxidant levels, and the activities of superoxide dismutase, catalase, and glutathione S-transferase (GST). Furthermore, GTPs downregulated 8-hydroxy-2-deoxyguanosine, advanced glycation end products, and hepatic oxidative stress markers, such as malondialdehyde and nitric oxide. Additionally, GTPs abrogated dysregulation in hepatic Kelch-like ECH-associated protein 1 and nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target gene expression [heme oxygenase 1, NAD(P)H:quinone oxidoreductase 1, and GST] and inhibited tumor necrosis factor-α, transforming growth factor-ß, and interleukin (IL)-1ß and IL-6 in the liver of treated mice. Finally, GTPs effectively attenuated D-Gal-induced edema, vacuole formation, and inflammatory cell infiltration. In conclusion, GTPs showed antioxidant and anti-inflammatory properties in D-Gal-induced aging mice, and may be considered a natural alternative to the effects of hepatic aging.

14.
Materials (Basel) ; 15(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36079294

RESUMO

Poor mechanical properties and durability of recycled aggregate concrete (RAC) hinder its application in the construction field. In this study, pre-wetted recycled coarse aggregate was used as the internal curing material for prepared RAC with low water-to-binder ratio (W/B), aiming to improve the mechanical properties and durability. The results show that the workability decreases with increasing contents of pre-wetted recycled coarse aggregate. The variation in compressive strength of RAC with different contents of pre-wetted recycled coarse aggregate is obvious within 28 d. After 28 d, the effect of internal curing of pre-wetted recycled coarse aggregate starts to occur, causing a sustained increase in compressive strength. The sealed concrete with 50% and 75% pre-wetted recycled coarse aggregate contents presents the highest compressive strength and better internal curing effect. The pre-wetted recycled coarse aggregate decreases the relative humidity inside the concrete and effectively inhibits the development of shrinkage in the early stages. The RAC with pre-wetted recycled coarse aggregate presents little effect on the drying shrinkage. Additionally, the electric flux of RAC cured for 28 d increases from 561C to 1001C, which presents good resistance to chloride permeation. Microscopic tests indicate that the incorporation of pre-wetted recycled coarse aggregate is beneficial to the improvements of internal structure of RAC.

15.
Materials (Basel) ; 15(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36500165

RESUMO

The CO2 emissions from the cement industry and the production of waste wood chips are increasing with the rapid growth of the construction industry. In order to develop a green environmental protection building material with low thermal conductivity and up to standard mechanical properties, in this study, pine waste wood chips were mixed into cement-based materials as fine aggregate, and three different kinds of cementitious binders were used, including sulfur aluminate cement (SAC), ordinary Portland cement (OPC), and granulated blast furnace slag (GBFS), to prepare a recycled light cementitious composite material. The mechanical, thermal conductivity, shrinkage, water absorption, and pore structure of a wood chip light cementitious composite material were studied by changing the Ch/B (the mass ratio of wood chip to binder). The results showed that the strength, dry density, and thermal conductivity of the specimens decreased significantly with the increase in the Ch/B, while the shrinkage, water absorption, and pore size increased with the increase in the Ch/B. By comparing three different kinds of cementitious binders, the dry density of the material prepared with OPC was 942 kg/m3, the compressive strength of the material prepared with SAC was 13.5 MPa, and the thermal conductivity of the material prepared with slag was the lowest at 0.15 W/m/K. From the perspective of low-cost and low-carbon emissions, it was determined that the best way to prepare a light cementitious composite with waste wood chips is to use granulated blast furnace slag (GBFS) as the cementitious binder.

16.
Sci Total Environ ; 803: 150135, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34525728

RESUMO

Carbonation treatment (CT) by alkaline fly ash (FA) affects the stability of potentially toxic elements (PTEs). This study investigated the leachability and environmental risk of six PTEs contained in FA during natural and accelerated carbonation (NC, AC) using two typical leaching scenarios with distilled water (DW) and acetic acid (AA). The leaching of Pb/Cu/Cr/Ni in solidified/stabilized FA decreased due to CT in DW leaching, but the leaching of Pb/Zn/Cu/Cd increased due to CT in AA leaching. The leaching of the six PTEs (especially Pb/Cd) in AA leaching was significantly higher than that in DW leaching. CT was a promoting factor to increase the environmental risk level of PTEs in FA leachate, especially in AA leaching with H+ input. In the early stage of NC, under DW leaching tests, the environmental risk level of PTEs in FA leachate can be weakened due to the formation of carbonate minerals in the FA matrix. However, excessive NC increases the environmental risk of leached PTEs due to the decalcification of carbonate minerals. Both NC and AC increased the potential environmental risk of PTEs contained in the carbonated FA matrix. The nucleation and dissolution of carbonate minerals were interdependent with the immobilization and leaching of PTEs, which played a dominant role in the CT and leaching tests respectively. They jointly affected the occurrence behavior of PTEs in the FA matrix in CT tests and the leachability of PTEs in leaching tests. This study demonstrates that it is more scientific to evaluate the leachability of PTEs in carbonated FA according to the actual disposal scenarios.


Assuntos
Metais Pesados , Eliminação de Resíduos , Carbono , Carbonatos , Cinza de Carvão , Incineração , Metais Pesados/análise , Material Particulado , Resíduos Sólidos/análise
17.
Food Res Int ; 162(Pt A): 112008, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461234

RESUMO

This study examined the chemical compounds and bioactivity of the aqueous extract of Clitoria ternatea blue petals and investigated its beneficial effects in vivo on a mouse model of obesity and metabolic syndrome. The extract mainly contained flavonoids, and nine compounds were tentatively identified. Male C57BL/6J mice were either fed a standard diet (SD) or a high-fat, high-fructose diet (HFFD) for 16 weeks, and HFFD-fed animals were treated with 0.25%, 0.5%, and 2% (w/w) of the aqueous extract in drinking water. The aqueous extract ameliorated oxidative stress and inflammation mediators. Furthermore, the aqueous extract reduced plasma leptin, free fatty acid, low-density lipoprotein cholesterol levels and hepatic malondialdehyde content. The aqueous extract significantly reduced total cholesterol and ameliorated insulin resistance. The results demonstrated that the aqueous extract of C. ternatea blue petals contains bioactive anthocyanins that exert substantial hypolipidemic and anti-inflammatory effects by promoting reverse cholesterol transport in HFFD-fed mice.


Assuntos
Clitoria , Frutose , Masculino , Camundongos , Animais , Frutose/efeitos adversos , Antocianinas , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/prevenção & controle , Inflamação/prevenção & controle , Estresse Oxidativo , Colesterol
18.
Front Pharmacol ; 12: 755366, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737707

RESUMO

The protein Klotho can significantly delay aging, so it has attracted widespread attention. Abnormal downregulation of Klotho has been detected in several aging-related diseases, such as Alzheimer's disease, kidney injury, cancer, chronic obstructive pulmonary disease (COPD), vascular disease, muscular dystrophy and diabetes. Conversely, many exogenous and endogenous factors, several drugs, lifestyle changes and genetic manipulations were reported to exert therapeutic effects through increasing Klotho expression. In recent years, Klotho has been identified as a potential autophagy regulator. How Klotho may contribute to reversing the effects of aging and disease became clearer when it was linked to autophagy, the process in which eukaryotic cells clear away dysfunctional proteins and damaged organelles: the abovementioned diseases involve abnormal autophagy. Interestingly, growing evidence indicates that Klotho plays a dual role as inducer or inhibitor of autophagy in different physiological or pathological conditions through its influence on IGF-1/PI3K/Akt/mTOR signaling pathway, Beclin 1 expression and activity, as well as aldosterone level, which can help restore autophagy to beneficial levels. The present review examines the role of Klotho in regulating autophagy in Alzheimer's disease, kidney injury, cancer, COPD, vascular disease, muscular dystrophy and diabetes. Targeting Klotho may provide a new perspective for preventing and treating aging-related diseases.

19.
Expert Rev Gastroenterol Hepatol ; 15(8): 879-890, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34225534

RESUMO

Introduction: Hepatic stellate cells (HSCs) are essential for physiological homeostasis of the liver extracellular matrix (ECM). Excessive transdifferentiation of HSC from a quiescent to an activated phenotype contributes to disrupt this balance and can lead to liver fibrosis. Accumulating evidence has suggested that nuclear receptors (NRs) are involved in the regulation of HSC activation, proliferation, and function. Therefore, these NRs may be therapeutic targets to balance ECM homeostasis and inhibit HSC activation in liver fibrosis.Areas covered: In this review, the authors summarized the recent progress in the understanding of the regulatory role of NRs in HSCs and their potential as drug targets in liver fibrosis.Expert opinion: NRs are still potential therapy targets for inhibiting HSCs activation and liver fibrosis. However, the development of NRs agonists or antagonists to inhibit HSCs requires fully consideration of systemic effects.


Assuntos
Células Estreladas do Fígado/fisiologia , Cirrose Hepática/fisiopatologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Animais , Matriz Extracelular/fisiologia , Células Estreladas do Fígado/efeitos dos fármacos , Homeostase , Humanos , Fígado/fisiologia , Fígado/fisiopatologia , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores
20.
Materials (Basel) ; 15(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35009403

RESUMO

Due to the large amount of old hardened cement mortar attached to the surface of aggregate and the internal micro-cracks formed by the crushing process, the water absorption, apparent density, and crushing index of recycled coarse aggregate are still far behind those of natural coarse aggregate. Based on the performance requirements of different qualities of recycled coarse aggregate, the performance differences of recycled coarse aggregate before and after physical strengthening were observed. The results showed that the physical strengthening technique can remove old hardened mortar and micro powder attached to the surface of recycled coarse aggregate by mechanical action, which can effectively improve the quality of recycled coarse aggregate. The optimum calcination temperature of the recycled coarse aggregate was 400 °C and the grinding time was 20 min. The contents of the attached mortar in recycled coarse aggregates of Class I, II, and III were 7.9%, 22.8%, and 39.7%, respectively. The quality of recycled coarse aggregate was closely related to the amount of mortar attached to the surface. The higher the mortar content, the higher the water absorption, lower apparent density, and higher crushing index of the recycled coarse aggregate.

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