Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 357
Filtrar
1.
Toxicol In Vitro ; 99: 105867, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848824

RESUMO

Pristimerin (Pris), a bioactive triterpenoid compound extracted from the Celastraceae and Hippocrateaceae families, has been reported to exhibit an anti-cancer property on various cancers. However, the effects of Pris on esophageal cancer are poorly investigated. This current study sought to explore the activity and underlying mechanism of Pris against human esophageal squamous cell carcinoma (ESCC) cells. We demonstrated that Pris showed cytotoxicity in TE-1 and TE-10 ESCC cell lines, and significantly inhibited cell viability in a concentration dependent manner. Pris induced G0/G1 phase arrest and triggered apoptosis. It was also observed that the intracellular ROS level was remarkedly increased by Pris treatment. Besides, the function of Pris mediating the activation of ER stress and the inhibition of AKT/GSK3ß signaling pathway in TE-1 and TE-10 cells was further confirmed, which resulted in cell growth inhibition. And moreover, we revealed that all of the above pathways were regulated through ROS generation. In conclusion, our findings suggested that Pris might be considered as a novel natural compound for the developing anti-cancer drug candidate for human esophageal cancer.

2.
Front Oncol ; 14: 1366079, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939341

RESUMO

Objective: To investigate the feasibility of leg wound closure and reconstruction of maxillofacial soft defect by a fusiform-designed skin paddle in fibula free flap (FFF). Methods: Fifty patients who underwent FFF for reconstruction of maxillofacial soft defect were divided into two groups. The fusiform group (20 patients) was treated using a fusiform-designed skin paddle in FFF (skin paddle width less than 2 cm), and leg wound was closed using primary suturing. Reconstruction of the maxillofacial soft defect or filling of dead space was achieved by folding the fusiform skin paddle. The conventional group (30 patients) was treated using the conventional-designed skin paddle (skin paddle width no less than 2.5 cm). The leg wound was closed using mattress suturing or skin graft, while reconstruction of the maxillofacial soft defect or filling of dead space by conventional way. The average postoperative length of hospital stay, healing time of leg wound, and post-surgical complications were recorded at least 6 months after the surgery. Results: Compared with traditional method, the fusiform-designed skin paddle reduced the average healing time of the leg wound (fusiform group: 11.05 days, conventional group: 14.77 days, P < 0.05). The average length-to-width ratio in fusiform group was significantly greater than that of in conventional group (fusiform group: 5.85, conventional group: 2.93, P < 0.05), and no difference was observed on the graft size of skin paddle between two groups (fusiform group: 23.13, conventional group: 27.13, P > 0.05). The post-surgical early complications of the leg wound in the conventional group were higher than that of in the fusiform group (fusiform group: 0%, conventional group: 6.67%), while the post-surgical late complication of the donor site between the two groups showed no case. Healing disorders of maxillofacial soft reconstruction in the conventional group were higher than that of in the fusiform group (fusiform group: 5.26%, conventional group: 20.69%). Conclusions: Fusiform-designed skin paddle for closure of the leg wound and maxillofacial soft defect is a feasible alternative to the conventional- designed skin paddle. The fusiform- designed skin paddle resulted in the less postoperative length of hospital stay, shorter healing time of leg wound and less complication.

3.
Int J Ophthalmol ; 17(3): 454-465, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721506

RESUMO

AIM: To identify disease-causative mutations in families with congenital cataract. METHODS: Two Chinese families with autosomal-dominant congenital cataract (ADCC) were recruited and underwent comprehensive eye examinations. Gene panel next-generation sequencing of common pathogenic genes of congenital cataract was performed in the proband of each family. Sanger sequencing was used to valid the candidate gene mutations and sequence the other family members for co-segregation analysis. The effect of sequence changes on protein structure and function was predicted through bioinformatics analysis. Major intrinsic protein (MIP)-wildtype and MIP-G29R plasmids were constructed and microinjected into zebrafish single-cell stage embryos. Zebrafish embryonic lens phenotypes were screened using confocal microscopy. RESULTS: A novel heterozygous mutation (c.85G>A; p.G29R) in the MIP gene was identified in the proband of one family. A known heterozygous mutation (c.97C>T; p.R33C; rs864309693) in MIP was found in the proband of another family. In-silico prediction indicated that the novel mutation might affect the MIP protein function. Zebrafish embryonic lens was uniformly transparent in both wild-type PCS2+MIP and mutant PCS2+MIP. CONCLUSION: Two missense mutations in the MIP gene in Chinese cataract families are identified, and one of which is novel. These findings expand the genetic spectrum of MIP mutations associated with cataracts. The functional studies suggest that the novel MIP mutation might not be a gain-of-function but a loss-of-function mutation.

4.
Nat Commun ; 15(1): 4416, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789426

RESUMO

Ferroelectric materials, whose electrical polarization can be switched under external stimuli, have been widely used in sensors, data storage, and energy conversion. Molecular orbital breaking can result in switchable structural and physical bistability in ferroelectric materials as traditional spatial symmetry breaking does. Differently, molecular orbital breaking interprets the phase transition mechanism from the perspective of electronics and sheds new light on manipulating the physical properties of ferroelectrics. Here, we synthesize a pair of organosilicon Schiff base ferroelectric crystals, (R)- and (S)-N-(3,5-di-tert-butylbenzylidene)-1-((triphenylsilyl)oxy)ethanamine, which show optically controlled phase transition accompanying the molecular orbital breaking. The molecular orbital breaking is manifested as the breaking and reformation of covalent bonds during the phase transition process, that is, the conversion between C = N and C-O in the enol form and C-N and C = O in the keto form. This process brings about photo-mediated bistability with multiple physical channels such as dielectric, second-harmonic generation, and ferroelectric polarization. This work further explores this newly developed mechanism of ferroelectric phase transition and highlights the significance of photo-mediated ferroelectric materials for photo-controlled smart devices and bio-sensors.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38795393

RESUMO

CONTEXT: In a clinical study, tirzepatide, a glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1 receptor agonist (GIP/GLP-1RA), provided superior glycemic control vs the GLP-1RA semaglutide. The physiologic mechanisms are incompletely understood. OBJECTIVE: To evaluate treatment effects by model-based analyses of mixed-meal tolerance test (MMTT) data. DESIGN: A 28-week double-blind, randomized, placebo-controlled trial. SETTING: Two clinical research centers in Germany. PATIENTS: Patients with type 2 diabetes treated with metformin. INTERVENTIONS: Tirzepatide 15 mg, semaglutide 1 mg, placebo. MAIN OUTCOME MEASURES: Glycemic control, model-derived ß-cell function indices including insulin secretion rate (ISR) at 7.2-mmol/L glucose (ISR7.2), ß-cell glucose (ß-CG) sensitivity, insulin sensitivity, and estimated hepatic insulin-to-glucagon ratio. RESULTS: Tirzepatide significantly reduced fasting glucose and MMTT total glucose area under the curve (AUC) vs semaglutide (P < 0.01). Incremental glucose AUC did not differ significantly between treatments; therefore, greater total glucose AUC reduction with tirzepatide was mainly attributable to greater suppression of fasting glucose. A greater reduction in total ISR AUC was achieved with tirzepatide vs semaglutide (P < 0.01), in the context of greater improvement in insulin sensitivity with tirzepatide (P < 0.01). ISR7.2 was significantly increased with tirzepatide vs semaglutide (P < 0.05), showing improved ß-CG responsiveness. MMTT-derived ß-CG sensitivity was increased but not significantly different between treatments. Both treatments reduced fasting glucagon and total glucagon AUC, with glucagon AUC significantly reduced with tirzepatide vs semaglutide (P < 0.01). The estimated hepatic insulin-to-glucagon ratio did not change substantially with either treatment. CONCLUSIONS: These results suggest that the greater glycemic control observed for tirzepatide manifests as improved fasting glucose and glucose excursion control, due to improvements in ISR, insulin sensitivity, and glucagon suppression.

6.
Int Wound J ; 21(4): e14718, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38571455

RESUMO

This study comprehensively compared the effects of laparoscopic and open radical cystectomies on postoperative wound infections and complications in patients with bladder cancer. We conducted a systematic search for relevant studies in PubMed, Embase, Google Scholar, Cochrane Library, China National Knowledge Infrastructure, and Wanfang databases, from database inception to October 2023. Two researchers independently screened the literature, extracted data, and assessed the quality based on the inclusion and exclusion criteria. Data analysis was performed using Stata 17.0 software. Overall, 16 studies involving 1427 patients with bladder cancer were included. The analysis revealed that, compared with open radical cystectomy, laparoscopic radical cystectomy significantly reduced the incidence of wound infections (odds ratio [OR] = 0.38, 95% confidence interval [CI]: 0.23-0.64, p < 0.001) and complications (OR = 0.35, 95%CI: 0.26-0.47, p < 0.001) and significantly shortened the hospital stay duration (standardised mean difference [SMD] = -1.85, 95%CI: -2.34 to -1.36, p < 0.001). Thus, this study determined that laparoscopic radical cystectomy for the treatment of bladder cancer effectively reduced the occurrence of wound infections and complications, and significantly shortened the patient's hospital stay, demonstrating notable therapeutic effectiveness worthy of clinical application.


Assuntos
Laparoscopia , Neoplasias da Bexiga Urinária , Humanos , Cistectomia/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/cirurgia , Resultado do Tratamento , Neoplasias da Bexiga Urinária/cirurgia , Laparoscopia/efeitos adversos
7.
Environ Sci Technol ; 58(15): 6835-6842, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38570313

RESUMO

Artificial ion channel membranes hold high promise in water treatment, nanofluidics, and energy conversion, but it remains a great challenge to construct such smart membranes with both reversible ion-gating capability and desirable ion selectivity. Herein, we constructed a smart MXene-based membrane via p-phenylenediamine functionalization (MLM-PPD) with highly stable and aligned two-dimensional subnanochannels, which exhibits reversible ion-gating capability and ultrahigh metal ion selectivity similar to biological ion channels. The pH-sensitive groups within the MLM-PPD channel confers excellent reversible Mg2+-gating capability with a pH-switching ratio of up to 100. The mono/divalent metal-ion selectivity up to 1243.8 and 400.9 for K+/Mg2+ and Li+/Mg2+, respectively, outperforms other reported membranes. Theoretical calculations combined with experimental results reveal that the steric hindrance and stronger PPD-ion interactions substantially enhance the energy barrier for divalent metal ions passing through the MLM-PPD, and thus leading to ultrahigh mono/divalent metal-ion selectivity. This work provides a new strategy for developing artificial-ion channel membranes with both reversible ion-gating functionality and high-ion selectivity for various applications.


Assuntos
Canais Iônicos , Metais , Nitritos , Elementos de Transição , Íons , Cátions Bivalentes , Membranas Artificiais , Concentração de Íons de Hidrogênio
9.
Chem Commun (Camb) ; 60(32): 4322-4325, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38535993

RESUMO

Here, we synthesized a series of cholesteryl-based compounds, whose phases and their transformation can be modulated by temperature and the chain length of the fluoroalkyl moieties. To our knowledge, this is the first time that the phase transition could be modulated with perfluoroalkyl tail engineering in organic single-component ferroelectric crystals.

10.
J Biomol Struct Dyn ; : 1-13, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345053

RESUMO

Pigment epithelium-derived factor (PEDF) could bind to vascular endothelial growth factor receptor 2 (VEGFR2) and inhibit its activation induced by VEGF. But how PEDF affects VEGFR2 pathway is still poorly understood. In this study, we elucidated the precise mechanism underlying the interaction between PEDF and VEGFR2, and subsequently corroborated our findings using a rat AMI model. PEDF prevented endocytosis of VE-cadherin induced by hypoxia, thereby protecting the endothelium integrity. A three-dimensional model of the VEGFR2-PEDF complex was constructed by protein-protein docking method. The results showed that the VEGFR2-PEDF complex was stable during the simulation. Hydrogen bonds, binding energy and binding modes were analyzed during molecular dynamics simulations, which indicated that hydrogen bonds and hydrophobic interactions were important for the recognition of VEGFR2 with PEDF. In addition, the results from exudation of fibrinogen suggested that PEDF inhibits vascular leakage in acute myocardial infarction and confirmed the critical role of key amino acids in the regulation of endothelial cell permeability. This observation is also supported by echocardiography studies showing that the 34mer peptide sustained cardiac function during acute myocardial infarction. Besides, PEDF and 34mer could inhibit the aggregation of myofiber in the heart and promoted the formation of a dense cell layer in cardiomyocytes, which suggested that PEDF and 34mer peptide protect against AMI-induced cardiac dysfunction. These results suggest that PEDF inhibits the phosphorylation of downstream proteins, thereby preventing vascular leakage, which provides a new therapeutic direction for the treatment of acute myocardial infarction.Communicated by Ramaswamy H. Sarma.

11.
Sci China Life Sci ; 67(2): 286-300, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37897614

RESUMO

We previously demonstrated that normal high-density lipoprotein (nHDL) can promote angiogenesis, whereas HDL from patients with coronary artery disease (dHDL) is dysfunctional and impairs angiogenesis. Autophagy plays a critical role in angiogenesis, and HDL regulates autophagy. However, it is unclear whether nHDL and dHDL regulate angiogenesis by affecting autophagy. Endothelial cells (ECs) were treated with nHDL and dHDL with or without an autophagy inhibitor. Autophagy, endothelial nitric oxide synthase (eNOS) expression, miRNA expression, nitric oxide (NO) production, superoxide anion (O2•-) generation, EC migration, and tube formation were evaluated. nHDL suppressed the expression of miR-181a-5p, which promotes autophagy and the expression of eNOS, resulting in NO production and the inhibition of O2•- generation, and ultimately increasing in EC migration and tube formation. dHDL showed opposite effects compared to nHDL and ultimately inhibited EC migration and tube formation. We found that autophagy-related protein 5 (ATG5) was a direct target of miR-181a-5p. ATG5 silencing or miR-181a-5p mimic inhibited nHDL-induced autophagy, eNOS expression, NO production, EC migration, tube formation, and enhanced O2•- generation, whereas overexpression of ATG5 or miR-181a-5p inhibitor reversed the above effects of dHDL. ATG5 expression and angiogenesis were decreased in the ischemic lower limbs of hypercholesterolemic low-density lipoprotein receptor null (LDLr-/-) mice when compared to C57BL/6 mice. ATG5 overexpression improved angiogenesis in ischemic hypercholesterolemic LDLr-/- mice. Taken together, nHDL was able to stimulate autophagy by suppressing miR-181a-5p, subsequently increasing eNOS expression, which generated NO and promoted angiogenesis. In contrast, dHDL inhibited angiogenesis, at least partially, by increasing miR-181a-5p expression, which decreased autophagy and eNOS expression, resulting in a decrease in NO production and an increase in O2•- generation. Our findings reveal a novel mechanism by which HDL affects angiogenesis by regulating autophagy and provide a therapeutic target for dHDL-impaired angiogenesis.


Assuntos
MicroRNAs , Humanos , Camundongos , Animais , MicroRNAs/metabolismo , Células Endoteliais/metabolismo , Angiogênese , Camundongos Endogâmicos C57BL , Autofagia/genética
12.
Hepatol Int ; 18(1): 4-31, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37864725

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignancies and the third leading cause of cancer-related deaths globally. Hepatic arterial infusion chemotherapy (HAIC) treatment is widely accepted as one of the alternative therapeutic modalities for HCC owing to its local control effect and low systemic toxicity. Nevertheless, although accumulating high-quality evidence has displayed the superior survival advantages of HAIC of oxaliplatin, fluorouracil, and leucovorin (HAIC-FOLFOX) compared with standard first-line treatment in different scenarios, the lack of standardization for HAIC procedure and remained controversy limited the proper and safe performance of HAIC treatment in HCC. Therefore, an expert consensus conference was held on March 2023 in Guangzhou, China to review current practices regarding HAIC treatment in patients with HCC and develop widely accepted statements and recommendations. In this article, the latest evidence of HAIC was systematically summarized and the final 22 expert recommendations were proposed, which incorporate the assessment of candidates for HAIC treatment, procedural technique details, therapeutic outcomes, the HAIC-related complications and corresponding treatments, and therapeutic scheme management.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Resultado do Tratamento , Artéria Hepática/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fluoruracila/uso terapêutico , Infusões Intra-Arteriais
13.
Food Chem ; 438: 137970, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37988934

RESUMO

Gelatin is a water-soluble protein obtained from the collagen of various animal origins (porcine, bovine, fish, donkey, horse, and deer hide) and has diverse applications in the food, pharmaceutical, and cosmetics industries. Porcine and bovine gelatins are extensively used in food and non-food products; however, their acceptance is limited due to religious prohibitions, whereas fish gelatin is accepted in all religions. In Southeast Asia, especially in China, gelatin obtained from donkey and deer skins is used in medicines. However, both sources suffer from adulteration (mixing different sources of gelatin) due to their limited availability and high cost. Unclear labeling and limited information about actual gelatin sources in gelatin-containing products cause serious concern among societies for halal and fraud authentication of gelatin sources. Therefore, authenticating gelatin sources in gelatin-based products is challenging due to close similarities between the composition differences and degradation of DNA and protein biomarkers in processed gelatin. Thus, different methods have been proposed to identify and quantify different gelatin sources in pharmaceutical and food products. To the best of our knowledge, this systematic and comprehensive review highlights different authentication techniques and their limitations in gelatin detection and quantification in various commercial products. This review also describes halal authentication and adulteration prevention strategies of various gelatin sources, mainly focussing on research gaps, challenges, and future directions in this research area.


Assuntos
Gelatina , Animais , Bovinos , Cervos , Equidae , Peixes , Alimentos , Gelatina/análise , Cavalos , Suínos
14.
Sci Total Environ ; 914: 169629, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38157906

RESUMO

High level dissolved B, which poses risks to human health, has been widely observed in geothermal water. In the Guide Basin, NW China, a series of geothermal water samples along a fault show a wide range of B contents ranging from 3.14 to 8.33 mg/L, which are higher than the WHO Guideline value equaling 2.4 mg/L in drinking water. To identify the sources and fate of B, we conduct a comprehensive analysis of hydrochemistry and stable isotopes (D, 18O and 11B) of three thermal fields representing three stages of hydrogeochemical evolution (stages I, II and III). From stage I to III, there are trends of increasing mineral dissolution, which is supported by increasing mean reservoir temperature and concentrations of conservative elements (Cl, Na, K, Li and Si). Geothermal water in stage I with meteoric origin and the lowest reservoir temperature has the highest B/Na resulting from silicate dissolution and falls on the mixing line between granitoids and cold water on the plot of δ11B versus 1/B, showing the control of silicate dissolution. However, geothermal water in stage III has lower Ca, B Sr and B/Na than that in stage II. Because of the occurrence of other processes, geothermal water in stages II and III deviates from the LMWL. Compared with geothermal water in stage I, the increased Sr/Ca and decreased B/Ca show that B are removed by both coprecipitation and vapor separation. With the aid of B isotopes, we find vapor separation dominates in stage II, whereas carbonate precipitation dominates in stage III. Overall, a combined use of three isotopes (H, O and B) and three element ratios (B/Na, B/Ca and Sr/Ca) leads to a complete understanding of B cycle and hydrogeochemical evolution in hydrothermal systems.

15.
ACS Appl Mater Interfaces ; 16(1): 1688-1704, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38110286

RESUMO

Fluorescent metal-organic frameworks (MOFs) are promising sensing materials with tunable and robust structural properties and remarkable luminescent capabilities. In this study, a novel dual-emission fluorescent metal-organic framework (EY@MOF-5) composite is synthesized by a one-pot bottle-around-ship approach. Eosin Y (EY) is encapsulated in MOF-5 to enhance its fluorescence properties and selectivity, effectively addressing typical MOF-5 limitations. EY@MOF-5 serves as a versatile dual-functional fluorescent sensor for two different analytes, daclatasvir (DCT) and nitenpyram (NTP), showing an impressive linear range of 10-200 nM and 0.1-300 µM, with detection limits of 233 pM and 65 nM, respectively. The established method is ultrafast, highly sensitive, and extremely selective for DCT and NTP detection in complex biological and food samples. Fluorescence results are compared and validated with the recommended UPLC method. Then, a smartphone-integrated sensing system is introduced for on-site, real-time, and quantitative analysis of DCT and NTP. The smartphone-assisted intelligent sensing method manifests promising results for DCT and NTP monitoring in biological and food samples, demonstrating its promising potential for the on-site detection of biologically and environmentally significant analytes.

16.
Anal Methods ; 15(44): 6009-6014, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37927098

RESUMO

Vitamin D (VD) metabolites are involved in a variety of important metabolic processes and physiological effects in organisms. Profiling of VD metabolites favors a deep understanding of the physiological role of VD. However, VD metabolites are difficult to detect due to their high chemical structural rigidity, structural similarity, and low sensitivities under liquid chromatography-tandem mass spectrometry (LC-MS). Herein, we present a chemical derivatization assisted LC-MS/MS strategy for the detection of VDs, in which 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) is employed to derivatize the conjugated diene of VD metabolites and provides sensitizing reporters for MS detection. After PTAD derivatization, the sensitivities of seven VD metabolites increased by 24-276 folds, with the limits of detection ranging from 3 to 20 pg mL-1. Using this method, we achieved a sensitive and accurate quantification of 7 VD metabolites (vitamin D2, vitamin D3, 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, 1,25-dihydroxyvitamin D2, 1,25-dihydroxyvitamin D3, and 1,24,25-trihydroxyvitamin D3) of the VD metabolic pathway in different trace biological samples, including human serum, mouse tissues (namely liver, kidney, lung, and spleen), and cells. We believe that the present method can provide a promising tool for an in-depth analysis of VD metabolism.


Assuntos
Espectrometria de Massas em Tandem , Vitamina D , Humanos , Camundongos , Animais , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Vitamina D/análise , Calcifediol/análise , Ergocalciferóis
17.
Environ Sci Pollut Res Int ; 30(58): 121929-121947, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37957496

RESUMO

Improvement in the photocatalytic selectivity is imperative for the effective and efficient utilization of catalysts. In this study, a molecularly imprinted polymer-coated iron-doped titanium dioxide (Fe-TiO2@MIP) nanocomposite was successfully synthesized by precipitation polymerization while using RB-19 as a template. The synthesized nanocomposites (Fe-TiO2@MIP and Fe-TiO2@NIP) were characterized by Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM) with energy dispersive X-ray (EDX), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-EMMETT-Teller (BET), and UV-visible spectrophotometry. The optimized binding experiments revealed a high imprinting factor of 5.0 for RB-19. The catalytic degradation efficiency and selectivity of Fe-TiO2@MIP enhanced to almost complete degradation of RB-19 from 70% for the parent Fe-TiO2 and 76% for Fe-TiO2@NIP. An outstanding degradation selectivity of RB-19 was achieved compared to other competitive dyes. Finally, the analysis of the non-degraded and degraded RB-19 by ESI-MS revealed the presence of different intermediates that fits well with the proposed degradation mechanism. The study opens new possibilities of selective photo-degradation of targeted contaminants that may ultimately lead to efficient use of photocatalysts.


Assuntos
Luz , Impressão Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Titânio/química , Catálise
18.
Chemosphere ; 342: 140136, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37699456

RESUMO

Clarifying the antibacterial mechanism of silver (Ag)-based materials is of great significance for the rational design, synthesis, and evaluation of antimicrobials. Herein, detailed description of the antibacterial mechanism of a synthesized silver deposited fullerene material (Ag(I)-C60) towards Staphylococcus aureus was surveyed from the point of view of DNA damage by ultraviolet-visible spectroscopy (UV-vis), inductively coupled plasma mass spectrometry (ICP-MS), and liquid chromatography-mass spectrometry (LC-MS). The model material, Ag(I)-C60, was prepared by liquid-liquid interfacial precipitation method, and characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermos-gravimetric analysis (TGA), and nitrogen adsorption/desorption analysis. Ultra-efficient bacteriostatic rate of Ag(I)-C60 was found to be 88.98% under light irradiation for 20 min. UV-vis measurement of the composition changes of four DNA bases showed that they changed in the presence of Ag(I)-C60 under light irradiation, suggesting Ag(I)-C60 could destroy the cells and genetic material of Staphylococcus aureus and thereby inhibit its growth and reproduction. ICP-MS analysis demonstrated the releasing behavior of Ag+ from Ag-based materials. Finally, the transformation pathway of G, A, C, and T were measured by LC-MS, demonstrating the conversion of Adenine (m/z 136.06) to 8-OH-Ade (m/z 174.04). These collective results suggested that Ag(I)-C60 was a new ultra-efficient antibacterial by slowly releasing Ag+ in water and producing a large amount of ROS under light.

19.
Environ Res ; 238(Pt 1): 117138, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37716395

RESUMO

Exploring the vegetation carbon cycle and the factors influencing vegetation carbon sequestration in areas with complex plateau-basin topography and fragile ecosystems is crucial. In this study, spatial and temporal characteristics of carbon sequestration by vegetation in Sichuan and Chongqing from 2010 to 2020 and the influencing factors were investigated through simulations of net primary productivity (NPP) using the modified Carnegie-Ames-Stanford approach (CASA) and the Thornthwaite Memorial (TM) model and using chemical equations of photochemical reactions. The results indicated that: The spatial distribution of carbon sequestration capacity (CSC) trends showed an increase in the east (the most prominent increased trend along the mountainous areas of the basin) and a decrease in the west (western Sichuan plateau). Differences exist in the impact factors of CSC in different regions. In the basin margins and mountainous areas, where the proportion of forests was high, a combination of climate change and human activities contributed to the increase in CSC. The relatively warm and humid meteorological conditions in the hinterland of the basin were more conducive to the increase in CSC, and climate change also affected the region more significantly. In contrast, in the relatively high altitude of western Sichuan, controlled human activities were the key to improving CSC. The results of the study contribute to the understanding of the basic theory of vegetation carbon cycle in areas with complex plateau-basin topography and fragile ecosystems, as well as to provide suggestions for ecological shelter construction and ecological restoration in the upper Yangtze River.


Assuntos
Sequestro de Carbono , Ecossistema , Humanos , Mudança Climática , Florestas , Atividades Humanas , China , Carbono
20.
Front Oncol ; 13: 1186674, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37427137

RESUMO

Developed in early 1980s, transarterial chemoembolization (TACE) with Lipiodol was adopted globally after large-scale randomized control trials and meta-analyses proving its effectiveness were completed. Also known as "conventional TACE" (cTACE), TACE is currently the first-line treatment for patients with unresectable intermediate stage hepatocellular carcinoma (HCC) and delivers both ischemic and cytotoxic effects to targeted tumors. Although new technology and clinical studies have contributed to a more comprehensive understanding of when and how to apply this widely-adopted therapeutic modality, some of these new findings and techniques have yet to be incorporated into a guideline appropriate for Taiwan. In addition, differences in the underlying liver pathologies and treatment practices for transcatheter embolization between Taiwan and other Asian or Western populations have not been adequately addressed, with significant variations in the cTACE protocols adopted in different parts of the world. These mainly revolve around the amount and type of chemotherapeutic agents used, the type of embolic materials, reliance on Lipiodol, and the degree of selectiveness in catheter positioning. Subsequently, interpreting and comparing results obtained from different centers in a systematic fashion remain difficult, even for experienced practitioners. To address these concerns, we convened a panel of experts specializing in different aspects of HCC treatment to devise modernized recommendations that reflect recent clinical experiences, as well as cTACE protocols which are tailored for use in Taiwan. The conclusions of this expert panel are described herein.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...