Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
1.
Sci Total Environ ; 927: 172149, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569970

RESUMO

Metalloid co-contamination such as arsenic (As) and antimony (Sb) in soils has posed a significant threat to ecological balance and human well-being. In this study, a novel magnetic graphene-loaded biochar gel (FeBG) was developed, and its remediation potential for the reclamation of AsSb spoiled soil was assessed through a six-month soil incubation experiment. Results showed that the incorporation of iron substances and graphene imparted FeBG with enhanced surface characteristics, such as the formation of a new FeO bond and an enlarged surface area compared to the pristine biochar (BC) (80.5 m2 g-1 vs 57.4 m2 g-1). Application of FeBG significantly decreased Na2HPO4-extractable concentration of As in soils by 9.9 %, whilst BC addition had a non-significant influence on As availability, compared to the control. Additionally, both BC (8.2 %) and FeBG (16.4 %) treatments decreased the Na2HPO4-extractable concentration of Sb in soils. The enhanced immobilization efficiency of FeBG for As/Sb could be attributed to FeBG-induced electrostatic attraction, complexation (Fe-O(H)-As/Sb), and π-π electron donor-acceptor coordination mechanisms. Additionally, the FeBG application boosted the activities of sucrase (9.6 %) and leucine aminopeptidase (7.7 %), compared to the control. PLS-PM analysis revealed a significant negative impact of soil physicochemical properties on the availability of As (ß = -0.611, P < 0.01) and Sb (ß = -0.848, P < 0.001) in soils, in which Sb availability subsequently led to a suppression in soil enzyme activities (ß = -0.514, P < 0.01). Overall, the novel FeBG could be a potential amendment for the simultaneous stabilization of As/Sb and the improvement of soil quality in contaminated soils.


Assuntos
Antimônio , Arsênio , Carvão Vegetal , Recuperação e Remediação Ambiental , Grafite , Mineração , Poluentes do Solo , Antimônio/química , Antimônio/análise , Grafite/química , Carvão Vegetal/química , Poluentes do Solo/análise , Arsênio/análise , Recuperação e Remediação Ambiental/métodos , Solo/química
2.
J Hazard Mater ; 469: 133937, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38460259

RESUMO

This study examined the effectiveness of pristine biochar (BC) and Fe-functionalized biochar (FBC) in remediating As-Sb co-contaminated soil, and revealed the resulting impact on soil enzymatic activities and bacterial communities. Results from incubation experiments showed that the 1.5% FBC treatment reduced the bioavailable As and Sb concentration by 13.5% and 27.1%, respectively, in compared to the control, and reduced the proportion of specifically adsorbed and amorphous Fe-Mn oxide-bound metal(loid) fractions in the treated soil. Among the BC treatments, only the 1.5% BC treatment resulted in a reduction of bioavailable As by 11.7% and Sb by 21.4%. The 0.5% BC treatment showed no significant difference. The FBC achieved high As/Sb immobilization efficiency through Fe-induced electrostatic attraction, π-π electron donor-acceptor coordination, and complexation (Fe-O(H)-As/Sb) mechanisms. Additionally, the 1.5% FBC treatment led to a 108.2% and 367.4% increase in the activities of N-acetyl-ß-glucosaminidase and urease in soils, respectively, compared to the control. Furthermore, it significantly increased the abundance of Proteobacteria (15.2%), Actinobacteriota (37.0%), Chloroflexi (21.4%), and Gemmatimonadota (43.6%) at the phylum level. Co-occurrence network analysis showed that FBC was better than BC in increasing the complexity of bacterial communities. Partial least squares path modeling further indicated that the addition of biochar treatments can affect soil enzyme activities by altering soil bacterial composition. This study suggests that FBC application offers advantages in simultaneous As and Sb immobilization and restructuring the bacterial community composition in metal(loid)-contaminated soil.


Assuntos
Arsênio , Poluentes do Solo , Antimônio , Arsênio/análise , Poluentes do Solo/análise , Carvão Vegetal , Bactérias , Solo
3.
J Food Sci ; 89(3): 1567-1581, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38343291

RESUMO

The study aimed to purify and characterize antioxidant peptides from chicken blood hemoglobin hydrolysate. The fraction M2  (< 3 KDa) with the strongest antioxidant activity was isolated by ultrafiltration, and its DPPH (1,1-diphenyl-2-picryl-hydrazyl radical) free radical scavenging rate, ABTS [2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate)] free radical scavenging rate, and iron ion chelation activity were 82.91%, 77.49%, and 80.99%, respectively. After in vitro digestion, the antioxidant capacity of chicken blood hydrolysate was significantly higher than that before digestion (p < 0.05). M2 exhibited the strongest antioxidant activity after stomach digestion, with a DPPH radical scavenging rate and iron ion chelating power of 82.91% and 79.61%, respectively. Component A was purified from M2 by Sephadex G-25 gel chromatography. The peptide sequences were identified by LC-MS/MS from fraction A, and four peptides, AEDKKLIQ (944.54 Da), APAPAAK (625.36 Da), LSDLHAHKL (1033.57 Da), and LSNLHAYNL (1044.54 Da) were synthesized using the solid-phase peptide method, among which APAPAAK was a novel antioxidant peptide. Molecular docking was used to simulate the binding of these four peptides to the key active site of Keap1 via hydrogen bonding. This study suggests that chicken blood may provide a new natural source of antioxidant peptides.


Assuntos
Antioxidantes , Galinhas , Animais , Antioxidantes/química , Proteína 1 Associada a ECH Semelhante a Kelch , Cromatografia Líquida , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2 , Espectrometria de Massas em Tandem , Peptídeos/química , Radicais Livres , Hemoglobinas , Digestão , Ferro
4.
Mol Cells ; 47(1): 100004, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38376482

RESUMO

Insulin is essential for maintaining normoglycemia and is predominantly secreted in response to glucose stimulation by ß-cells. Incretin hormones, such as glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide, also stimulate insulin secretion. However, as obesity and type 2 diabetes worsen, glucose-dependent insulinotropic polypeptide loses its insulinotropic efficacy, whereas GLP-1 receptor (GLP-1R) agonists continue to be effective owing to its signaling switch from Gs to Gq. Herein, we demonstrated that endoplasmic reticulum (ER) stress induced a transition from Gs to Gq in GLP-1R signaling in mouse islets. Intriguingly, chemical chaperones known to alleviate ER stress, such as 4-PBA and TUDCA, enforced GLP-1R's Gq utilization rather than reversing GLP-1R's signaling switch induced by ER stress or obese and diabetic conditions. In addition, the activation of X-box binding protein 1 (XBP1) or activating transcription factor 6 (ATF6), 2 key ER stress-associated signaling (unfolded protein response) factors, promoted Gs utilization in GLP-1R signaling, whereas Gq employment by ER stress was unaffected by XBP1 or ATF6 activation. Our study revealed that ER stress and its associated signaling events alter GLP-1R's signaling, which can be used in type 2 diabetes treatment.


Assuntos
Estresse do Retículo Endoplasmático , Receptor do Peptídeo Semelhante ao Glucagon 1 , Ilhotas Pancreáticas , Resposta a Proteínas não Dobradas , Animais , Camundongos , Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Glucose , Insulina
5.
Korean J Physiol Pharmacol ; 28(1): 31-38, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38154962

RESUMO

As in type 1 diabetes, the loss of pancreatic ß-cells leads to insulin deficiency and the subsequent development of hyperglycemia. Exercise has been proposed as a viable remedy for hyperglycemia. Lithium, which has been used as a treatment for bipolar disorder, has also been shown to improve glucose homeostasis under the conditions of obesity and type 2 diabetes by enhancing the effects of exercise on the skeletal muscles. In this study, we demonstrated that unlike in obesity and type 2 diabetic conditions, under the condition of insulin-deficient type 1 diabetes, lithium administration attenuated pancreatic a-cell mass without altering insulin-secreting ß-cell mass, implying a selective impact on glucagon production. Additionally, we also documented that lithium downregulated the hepatic gluconeogenic program by decreasing G6Pase protein levels and upregulating AMPK activity. These findings suggest that lithium's effect on glucose metabolism in type 1 diabetes is mediated through a different mechanism than those associated with exerciseinduced metabolic changes in the muscle. Therefore, our research presents the novel therapeutic potential of lithium in the treatment of type 1 diabetes, which can be utilized along with insulin and independently of exercise.

6.
Nat Commun ; 14(1): 8407, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110399

RESUMO

Studying complex relaxation behaviors is of critical importance for understanding the nature of glasses. Here we report a Kovacs-like memory effect in glasses, manifested by non-monotonic stress relaxation during two-step high-to-low strains stimulations. During the stress relaxation process, if the strain jumps from a higher state to a lower state, the stress does not continue to decrease, but increases first and then decreases. The memory effect becomes stronger when the atomic motions become highly collective with a large activation energy, e.g. the strain in the first stage is larger, the temperature is higher, and the stimulation is longer. The physical origin of the stress memory effect is studied based on the relaxation kinetics and the in-situ synchrotron X-ray experiments. The stress memory effect is probably a universal phenomenon in different types of glasses.

7.
Environ Pollut ; 337: 122637, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37769707

RESUMO

Sorption and oxidation are two potential pathways for the decontamination of trivalent antimony (Sb(III))-bearing water, using iron (Fe)-modified biochar (FeBC). Here we investigated the sorption and oxidation behavior of FeBC for Sb(III) in aqueous solutions. Results revealed that Sb(III) removal by FeBC was significantly improved showing the maximum Sb(III) sorption (64.0 mg g-1). Density functional theory (DFT) calculations indicated that magnetite (Fe3O4) in FeBC offered a sorption energy of -0.22 eV, which is 5 times that of non-modified biochar. With the addition of peroxymonosulfate (PMS), the sorption of Sb(III) on FeBC was 7 times higher than that on BC, indicating the sorption capacity of FeBC for Sb(III) could be substantially increased by adding oxidizing agents. Electrochemical analysis showed that Fe modification imparted FeBC higher electron-donating capacity than that of BC (0.045 v. s. 0.023 mmol e- (g biochar)-1), which might be the reason for the strong Sb(III) oxidation (63.6%) on the surface of FeBC. This study provides new information that is key for the development of effective biochar-based composite materials for the removal of Sb(III) from drinking water and wastewater. The findings from this study have important implications for protecting human health and agriculture.


Assuntos
Ferro , Poluentes Químicos da Água , Humanos , Ferro/análise , Antimônio/análise , Elétrons , Adsorção , Carvão Vegetal , Água , Estresse Oxidativo , Poluentes Químicos da Água/análise
8.
Europace ; 25(11)2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37757839

RESUMO

AIMS: While numerous studies have demonstrated favourable safety and efficacy of the excimer laser sheath for transvenous lead extraction (TLE) in smaller cohorts, comprehensive large-scale investigations with contemporary data remain scarce. This study aims to evaluate the safety and performance of laser-assisted TLE through a meta-analysis of contemporary data. METHODS AND RESULTS: A systematic literature search was conducted to identify articles that assessed the safety and performance of the spectranetics laser sheath (SLS) II and GlideLight Excimer laser sheaths in TLE procedures between 1 April 2016 and 31 March 2021. Safety outcomes included procedure-related death and major/minor complications. Performance outcomes included procedural and clinical success rates. A random-effects, inverse-variance-weighting meta-analysis was performed to obtain the weighted average of the evaluated outcomes. In total, 17 articles were identified and evaluated, including 1729 patients with 2887 leads. Each patient, on average, had 2.3 ± 0.3 leads with a dwell time of 7.9 ± 3.0 years. The TLE procedural successes rate was 96.8% [1440/1505; 95% CI: (94.9-98.2%)] per patient and 96.3% [1447/1501; 95% CI: (94.8-97.4%)] per lead, and the clinical success rate per patient was 98.3% [989/1010, 95% CI: (97.4-99.0%)]. The procedure-related death rate was 0.08% [7/1729, 95% CI: (0.00%, 0.34%)], with major and minor complication rates of 1.9% [41/1729; 95% CI: (1.2-2.8%)] and 1.9% [58/1729; 95% CI: (0.8-3.6%)], respectively. CONCLUSION: This meta-analysis demonstrated that excimer laser sheath-assisted TLE has high success and low procedural mortality rates. It provides clinicians with a reliable and valuable resource for extracting indwelling cardiac leads which require advanced extraction techniques.


Assuntos
Remoção de Dispositivo , Humanos , Remoção de Dispositivo/efeitos adversos , Remoção de Dispositivo/métodos , Lasers de Excimer/efeitos adversos , Marca-Passo Artificial , Estudos Retrospectivos , Resultado do Tratamento
9.
Am J Physiol Endocrinol Metab ; 325(5): E448-E465, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37729023

RESUMO

Pancreatic ß-cell dysfunction and eventual loss are key steps in the progression of type 2 diabetes (T2D). Endoplasmic reticulum (ER) stress responses, especially those mediated by the protein kinase RNA-like ER kinase and activating transcription factor 4 (PERK-ATF4) pathway, have been implicated in promoting these ß-cell pathologies. However, the exact molecular events surrounding the role of the PERK-ATF4 pathway in ß-cell dysfunction remain unknown. Here, we report our discovery that ATF4 promotes the expression of PDE4D, which disrupts ß-cell function via a downregulation of cAMP signaling. We found that ß-cell-specific transgenic expression of ATF4 led to early ß-cell dysfunction and loss, a phenotype that resembles accelerated T2D. Expression of ATF4, rather than C/EBP homologous protein (CHOP), promoted PDE4D expression, reduced cAMP signaling, and attenuated responses to incretins and elevated glucose. Furthermore, we found that ß-cells of leptin receptor-deficient diabetic (db/db) mice had elevated nuclear localization of ATF4 and PDE4D expression, accompanied by impaired ß-cell function. Accordingly, pharmacological inhibition of the ATF4 pathway attenuated PDE4D expression in the islets and promoted incretin-simulated glucose tolerance and insulin secretion in db/db mice. Finally, we found that inhibiting PDE4 activity with selective pharmacological inhibitors improved ß-cell function in both db/db mice and ß-cell-specific ATF4 transgenic mice. In summary, our results indicate that ER stress causes ß-cell failure via ATF4-mediated PDE4D production, suggesting the ATF4-PDE4D pathway could be a therapeutic target for protecting ß-cell function during the progression of T2D.NEW & NOTEWORTHY Endoplasmic reticulum stress has been implied to cause multiple ß-cell pathologies during the progression of type 2 diabetes (T2D). However, the precise molecular events underlying this remain unknown. Here, we discovered that elevated ATF4 activity, which was seen in T2D ß cells, attenuated ß-cell proliferation and impaired insulin secretion via PDE4D-mediated downregulation of cAMP signaling. Additionally, we demonstrated that pharmacological inhibition of the ATF4 pathway or PDE4D activity alleviated ß-cell dysfunction, suggesting its therapeutic usefulness against T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Camundongos , Animais , Apoptose , Incretinas/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/metabolismo , Estresse do Retículo Endoplasmático/genética , Glucose/metabolismo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , eIF-2 Quinase/metabolismo
10.
Proc Natl Acad Sci U S A ; 120(20): e2302776120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155861

RESUMO

Nonexponential relaxations are universal characteristics for glassy materials. There is a well-known hypothesis that nonexponential relaxation peaks are composed of a series of exponential events, which have not been verified. In this Letter, we discover the exponential relaxation events during the recovery process using a high-precision nanocalorimetry, which are universal for metallic glasses and organic glasses. The relaxation peaks can be well fitted by the exponential Debye function with a single activation energy. The activation energy covers a broad range from α relaxation to ß relaxation and even the fast γ/ß' relaxation. We obtain the complete spectrum of the exponential relaxation peaks over a wide temperature range from 0.63Tg to 1.03Tg, which provides solid evidence that nonexponential relaxation peaks can be decomposed into exponential relaxation units. Furthermore, the contribution of different relaxation modes in the nonequilibrium enthalpy space is measured. These results open a door for developing the thermodynamics of nonequilibrium physics and for precisely modulating the properties of glasses by controlling the relaxation modes.

11.
Environ Int ; 176: 107989, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37245444

RESUMO

Sustainable management of ever-increasing organic biowaste and arable soil contamination by potentially toxic elements are of concern from both environmental and agricultural perspectives. To tackle the waste issue of crawfish shells and simultaneously minimize the threat of arsenic (As) and lead (Pb) to human health, a pot trial was conducted using chitin (CT), crawfish shell biochar (CSB), crawfish shell powder (CSP), and CT-CSB composite to compare their remediation efficiencies in As/Pb co-contaminated soil. Results demonstrated that addition of all amendments decreased Pb bioavailability, with the greatest effect observed for the CT-CSB treatment. Application of CSP and CSB increased the soil available As concentration, while significant decreases were observed in the CT and CT-CSB treatments. Meanwhile, CT addition was the most effective in enhancing the soil enzyme activities including acid phosphatase, α-glucosidase, N-acetyl-ß-glucosaminidase, and cellobiohydrolase, whereas CSB-containing treatments suppressed the activities of most enzymes. The amendments altered the bacterial abundance and composition in soil. For instance, compared to the control, all treatments increased Chitinophagaceae abundance by 2.6-4.7%. The relative abundance of Comamonadaceae decreased by 1.6% in the CSB treatment, while 2.1% increase of Comamonadaceae was noted in the CT-CSB treatment. Redundancy and correlation analyses (at the family level) indicated that the changes in bacterial community structure were linked to bulk density, water content, and As/Pb availability of soils. Partial least squares path modeling further indicated that soil chemical property (i.e., pH, dissolved organic carbon, and cation exchange capacity) was the strongest predictor of As/Pb availability in soils following amendment application. Overall, CT-CSB could be a potentially effective amendment for simultaneously immobilizing As and Pb and restoring soil ecological functions in contaminated arable soils.


Assuntos
Arsênio , Metais Pesados , Poluentes do Solo , Humanos , Arsênio/análise , Chumbo/análise , Disponibilidade Biológica , Quitina , Rizosfera , Metais Pesados/análise , Carvão Vegetal/química , Solo/química , Bactérias , Poluentes do Solo/análise , Cádmio/análise
12.
Environ Pollut ; 317: 120847, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36496064

RESUMO

The combined effects of graphene and biochar for enhanced adsorption of organic pollutants have not been demonstrated yet. Therefore, the mechanisms of graphene-modified biochar synthesis and its application to adsorption of contaminants remain unclear. In this study, the effect of flake-size graphene on biochar modification and its bisphenol S (BPS) adsorption performance was explored for the first time. Three sizes of graphene oxide were used as the precursor to prepare graphene/biochar composites using pyrolysis. It was found that the graphene with a small flake size was interspersed in the macropores of biochar, while the biochar was completely or mostly wrapped by the large-sized graphene sheet, which effectively prevented the agglomeration and pore blockage of biochar. Large-flake graphene oxide modified biochar (LGB) showed the highest adsorption capacity towards BPS, exhibiting 2.8 times higher adsorption than pristine biochar. Density functional theory (DFT) calculation suggested that the maximum diffusion barrier of O atoms in graphene coated cellulose (most frequently used biochar representative) could be reduced significantly (∼46%) at pyrolysis temperature of 873 K. Taking the advantage of small amount of graphene and enhanced adsorption performance, LGB could be a promising adsorbent for the removal of certain organic pollutants from wastewater and is conducive for the development of high-valued biochar modification.


Assuntos
Poluentes Ambientais , Grafite , Poluentes Químicos da Água , Adsorção , Água , Carvão Vegetal , Poluentes Químicos da Água/análise , Cinética
13.
JAMA Netw Open ; 5(12): e2248159, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36542378

RESUMO

Importance: Despite historically high rates of use, most inferior vena cava (IVC) filters are not retrieved. The US Food and Drug Administration safety communications recommended retrieval when the IVC filter is no longer indicated out of concern for filter-related complications. However, failure rates are high when using standard techniques for retrieval of long-dwelling filters, and until recently, there have been no devices approved for retrieval of embedded IVC filters. Objective: To evaluate the safety and success of excimer laser sheath-assisted retrieval of embedded IVC filters. Design, Setting, and Participants: A retrospective, multicenter, clinical cohort study of excimer laser sheath-assisted IVC filter retrievals from 7 US sites was conducted between March 1, 2012, and February 28, 2021, among 265 patients who underwent IVC filter retrieval using the laser. Patients were substratified between a high-volume single center and a multicenter data set. A blinded physician committee adjudicated reported complications and their association with use of the laser. Exposures: Retrieval of IVC filters using excimer laser sheath. Main Outcomes and Measures: The primary safety end point was device-related major complication rate (Society of Interventional Radiology categories C to F, which included any adverse event associated with morbidity or disability that increases the level of care, results in hospital admission, or substantially lengthens the hospital stay). The primary success end point was technical success of IVC filter retrieval. The primary end points were compared with literature-derived, meta-analysis-suggested target performance goals. Results: The single-center experience included 139 participants (mean [SD] age, 52 [16] years; 78 female participants [56.1%]), and the multicenter experience included 126 participants (mean [SD] age, 52 [16] years; 75 female participants [59.5%]). The device-related major complication rate was 2.9% (4 of 139; 95% CI, 0.8%-7.2%; P = .001) for the single-center experience and 4.0% (5 of 126; 95% CI, 1.3%-9.0%; P = .01) for the multicenter experience, both of which were significantly lower than the primary safety performance goal (10%). No major complications were considered to be definitively associated with use of the laser. The technical success rate was 95.7% (133 of 139; 95% CI, 90.8%-98.4%; P = .007) for the single-center experience and 95.2% (120 of 126; 95% CI, 89.9%-98.2%; P = .02) for the multicenter experience, both of which were significantly higher than the primary performance goal (89.4%). Conclusions and Relevance: This cohort study demonstrated high technical success and low complication rates of excimer laser sheath-assisted retrieval of embedded IVC filters in centers with variable case volume and experience, which suggests a wide applicability of the technique with proper training. The excimer laser sheath offers physicians a valuable tool for retrieval of challenging embedded IVC filters.


Assuntos
Lasers de Excimer , Filtros de Veia Cava , Humanos , Feminino , Pessoa de Meia-Idade , Lasers de Excimer/uso terapêutico , Estudos de Coortes , Estudos Retrospectivos , Remoção de Dispositivo/efeitos adversos , Remoção de Dispositivo/métodos , Estudos Multicêntricos como Assunto
14.
Environ Pollut ; 310: 119819, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35870525

RESUMO

Garden pruning waste is becoming a problem that intensifies the garbage siege. It is of great significance to purify polluted water using biochar prepared from garden pruning waste. Herein, the interaction mechanism between BPS and oriental plane tree biochar (TBC) with different surface functional groups was investigated by adsorption experiments, spectroscopic analysis and theoretical calculations. Adsorption kinetics and isotherm of BPS on TBC can be satisfactorily fitted into pseudo-second-order kinetic and Langmuir models, respectively. A rapid adsorption kinetic toward BPS was achieved by TBC in 15 min. As compared with TBC prepared at low temperature (300 °C) (LTBC), the maximum adsorption capacity of TBC prepared at high temperature (600 °C) (HTBC) can be significantly improved from 46.7 mg g-1 to 72.9 mg g-1. Besides, the microstructure and surface functional groups of HTBC were characterized using SEM, BET-N2, and XPS analysis. According to density functional theory (DFT) theoretical calculations, the higher adsorption energy of HTBC for BPS was mainly attributed to π-π interaction rather than hydrogen bonding, which was further supported by the analysis of FTIR and Raman spectra as well as the adsorption thermodynamic parameters. These findings suggested that by improving π-π interaction through high pyrolysis temperature, BPS could be removed and adsorbed by biochar with high efficacy, cost-efficiency, easy availability, and carbon-negative in nature, contributing to global carbon neutrality.


Assuntos
Árvores , Poluentes Químicos da Água , Adsorção , Carbono , Carvão Vegetal , Cinética , Fenóis , Sulfonas , Termodinâmica
15.
Chin J Physiol ; 65(2): 72-79, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35488672

RESUMO

Buyang Huanwu decoction (BYHWD), a classical prescription for ischemic stroke, has been reported to promote angiogenesis after focal ischemia. However, the mechanisms of the contribution of BYHWD on angiogenesis are still unclear. Connexin 43 (Cx43) played important roles in the functions of neurogliovascular unit. Therefore, the aim of this study was to explore the potential role of Cx43 in angiogenesis of the ischemic brain after BYHWD treatment. Middle cerebral artery occlusion (MCAO) was used to establish the model of focal ischemia. BYHWD was administrated intragastrically twice a day after MCAO with or without Gap26 (a specific Cx43 inhibitor). Western blot, neurological deficits, immunofluorescent staining, and Evans blue dye were used to confirm the role of Cx43 in angiogenesis after BYHWD treatment. The expression levels of total Cx43 and phosphorylated Cx43 were upregulated by BYHWD and peaked at 7 days post MCAO. Inhibition of Cx43 with Gap26 significantly attenuated the protective role of BYHWD in neurological behavior. BYHWD treatment promoted angiogenesis demonstrated by increased microvascular density, upregulated vascular endothelial growth factor (VEGF), and angiopoietin-1 (Ang-1), while inhibition of Cx43 with Gap26 attenuated these effects of BYHWD. In addition, Gap26 inhibited the beneficial effect of BYHWD on blood-brain barrier (BBB) integrity. These results suggested that Cx43 mediated the angiogenesis of BYHWD via VEGF and Ang-1 after focal ischemic stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Angiopoietina-1 , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Conexina 43 , Medicamentos de Ervas Chinesas , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
J Hazard Mater ; 425: 127971, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-34894506

RESUMO

Contamination of aquatic systems by antimony (Sb) is a worldwide issue due to its risks to eco-environment and human health. Batch sorption experiments were conducted to assess the equilibrium, kinetics and thermodynamics of antimonite [Sb(III)] sorption by pristine biochar (BC) and chitosan-loaded biochar (CHBC) derived from branches of Ficus microcarpa. Results showed the successful loading of chitosan onto biochar surface, exhibiting more functional groups (e.g., CO, -NH2, and -OH). Langmuir model well described the Sb(III) sorption isotherm experimental data, and the maximum sorption capacity of Sb(III) by CH1BC (biochar loaded with chitosan at a ratio of 1:1) was 168 mg g-1, whereas for the BC it was only 10 mg g-1. X-ray photoelectron spectroscopy demonstrated that CH1BC oxidized 86% of Sb(III) to Sb(V), while BC oxidized 71% of Sb(III). Density functional theory calculations suggested that the synergistic effect of exogenous hydroxyl and inherent carbonyl contributed to the enhanced removal efficiency of Sb(III) by CHBC. Key mechanisms for Sb(III) sorption onto CHBCs included electrostatic interaction, chelation, surface complexation, π-π interaction, and hydrogen bonding. Overall, this study implies that CHBC can be a new, viable sorbent for the removal of Sb(III) from aquatic systems aiding their safe and sustainable management.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Antimônio , Carvão Vegetal , Humanos , Cinética , Poluentes Químicos da Água/análise
17.
Front Psychol ; 12: 741065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721216

RESUMO

Background: Online review, as an important way of electronic word-of-mouth (eWOM) communication, plays an important role in e-commerce. However, few studies have examined the dark side of online reviews and their effect on consumers' purchase intentions. Information inconsistency is one of the dark sides that plays a critical role in influencing consumers' purchase intentions through online reviews. Methods: Using a 2*2 between-subject design that explores the main effects of the type of information inconsistency (vertical- vs. horizontal-attribute inconsistency) on purchase intention and the moderating effect of product type (search vs. experience product). Results: This study examines whether and how the type of information inconsistency between online recommendations and reviews influences consumer purchase decision-making. Conclusions: The findings show that vertical-attribute inconsistency leads to a lower purchase intention for search products; moreover, both vertical- and horizontal-attribute inconsistencies have no significant effect on purchase intention for experience products.

18.
Cell Rep ; 36(6): 109523, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34380032

RESUMO

Correct positioning of T cells within infected tissues is critical for T cell activation and pathogen control. Upon tissue entry, effector T cells must efficiently locate antigen-presenting cells (APC) for peripheral activation. We reveal that tissue entry and initial peripheral activation of Th1 effector T cells are tightly linked to perivascular positioning of chemokine-expressing APCs. Dermal inflammation induces tissue-wide de novo generation of discrete perivascular CXCL10+ cell clusters, enriched for CD11c+MHC-II+ monocyte-derived dendritic cells. These chemokine clusters are "hotspots" for both Th1 extravasation and activation in the inflamed skin. CXCR3-dependent Th1 localization to the cluster micro-environment prolongs T-APC interactions and boosts function. Both the frequency and range of these clusters are enhanced via a T helper 1 (Th1)-intrinsic, interferon-gamma (IFNγ)-dependent positive-feedback loop. Thus, the perivascular CXCL10+ clusters act as initial peripheral activation niches, optimizing controlled activation broadly throughout the tissue by coupling Th1 tissue entry with enhanced opportunities for Th1-APC encounter.


Assuntos
Células Apresentadoras de Antígenos/metabolismo , Quimiocina CXCL10/metabolismo , Ativação Linfocitária/imunologia , Células Th1/imunologia , Animais , Antígenos/metabolismo , Antígenos CD/metabolismo , Agregação Celular , Orelha/patologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Inflamação/patologia , Interferon gama , Camundongos , Camundongos Transgênicos , Receptores CXCR3/metabolismo , Pele/patologia
19.
New Phytol ; 230(5): 2029-2046, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33595857

RESUMO

Calcium-dependent protein kinases (CDPKs) play vital roles in metabolic regulations and stimuli responses in plants. However, little is known about their function in grapevine. Here, we report that VpCDPK9 and VpCDPK13, two paralogous CDPKs from Vitis pseudoreticulata accession Baihe-35-1, appear to positively regulate powdery mildew resistance. The transcription of them in leaves of 'Baihe-35-1' were differentially induced upon powdery mildew infection. Overexpression of VpCDPK9-YFP or VpCDPK13-YFP in the V. vinifera susceptible cultivar Thompson Seedless resulted in enhanced resistance to powdery mildew (YFP, yellow fluorescent protein). This might be due to elevation of SA and ethylene production, and excess accumulation of H2 O2 and callose in penetrated epidermal cells and/or the mesophyll cells underneath. Ectopic expression of VpCDPK9-YFP in Arabidopsis resulted in varied degrees of reduced stature, pre-mature senescence and enhanced powdery mildew resistance. However, these phenotypes were abolished in VpCDPK9-YFP transgenic lines impaired in SA signaling (pad4sid2) or ethylene signaling (ein2). Moreover, both of VpCDPK9 and VpCDPK13 were found to interact with and potentially phosphorylate VpMAPK3, VpMAPK6, VpACS1 and VpACS2 in vivo (ACS, 1-aminocyclopropane-1-carboxylic acid (ACC) synthase; MAPK, mitogen-activated protein kinase). These results suggest that VpCDPK9 and VpCDPK13 contribute to powdery mildew resistance via positively regulating SA and ethylene signaling in grapevine.


Assuntos
Arabidopsis , Ascomicetos , Vitis , Arabidopsis/genética , China , Resistência à Doença/genética , Doenças das Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Proteínas Quinases/genética , Vitis/genética
20.
Neurophotonics ; 7(1): 015004, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32042853

RESUMO

Significance: Cortically implanted microelectrode arrays provide a direct interface with neuronal populations and are used to restore movement capabilities and provide sensory feedback to patients with paralysis or amputation. Penetrating electrodes experience high rates of signal degradation within the first year that limit effectiveness and lead to eventual device failure. Aim: To assess vascular and neuronal changes over time in mice with implanted electrodes and examine the contribution of the brain tissue response to electrode performance. Approach: We used a multimodal approach combining in vivo electrophysiology and subcellular-level optical imaging. Results: At acute timescales, we observed structural damage from the mechanical trauma of electrode insertion, evidenced by severed dendrites in the electrode path and local hypofluorescence. Superficial vessel growth and remodeling occurred within the first few weeks in both electrode-implanted and window-only animals, but the deeper capillary growth evident in window-only animals was suppressed in electrode-implanted animals. After longer implantation periods, there was evidence of degeneration of transected dendrites superficial to the electrode path and localized neuronal cell body loss, along with deep vascular velocity changes near the electrode. Total spike rate (SR) across all animals reached a peak between 3 and 9 months postimplantation, then decreased. The local field potential signal remained relatively constant for up to 6 months, particularly in the high-gamma band, indicating long-term electrode viability and neuronal functioning at further distances from the electrode, but it showed a reduction in some animals at later time points. Most importantly, we found that progressive high-gamma and SR reductions both correlate positively with localized cell loss and decreasing capillary density within 100 µ m of the electrode. Conclusions: This multifaceted approach provided a more comprehensive picture of the ongoing biological response at the brain-electrode interface than can be achieved with postmortem histology alone and established a real-time relationship between electrophysiology and tissue damage.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...