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1.
Proc Natl Acad Sci U S A ; 120(10): e2206619120, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36848552

RESUMO

Selective oxidation of methane to organic oxygenates over metal-organic frameworks (MOFs) catalysts at low temperature is a challenging topic in the field of C1 chemistry because of the inferior stability of MOFs. Modifying the surface of Cu-BTC via hydrophobic polydimethylsiloxane (PDMS) at 235 °C under vacuum not only can dramatically improve its catalytic cycle stability in a liquid phase but also generate coordinatively unsaturated Cu(I) sites, which significantly enhances the catalytic activity of Cu-BTC catalyst. The results of spectroscopy characterizations and theoretical calculation proved that the coordinatively unsaturated Cu(I) sites made H2O2 dissociative into •OH, which formed Cu(II)-O active species by combining with coordinatively unsaturated Cu(I) sites for activating the C-H bond of methane. The high productivity of C1 oxygenates (CH3OH and CH3OOH) of 10.67 mmol gcat.-1h-1 with super high selectivity of 99.6% to C1 oxygenates was achieved over Cu-BTC-P-235 catalyst, and the catalyst possessed excellent reusability.

2.
Anal Biochem ; 688: 115472, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38266666

RESUMO

Due to the late detection of stomach cancer, this cancer usually causes high mortality. The development of an electrochemical genosensor to measure microRNA 106b (miR-106b), as a gastric cancer biomarker, is the aim of this effort. In this regard, first, 1,3,5-benzenetricarboxylate (BTC) metal-organic frameworks (Zn-BTC MOF) were self-assembled on the glassy carbon electrode and then the probe (ssDNA) was immobilized on it. The morphology Zn-BTC MOF was characterized by SEM, FT-IR, Raman and X-Ray techniques. Zn-BTC MOF as a biosensor substrate has strong interaction with ssDNA. Quantitative measurement of miR-106b was performed by electrochemical impedance spectroscopy (EIS). To perform this measurement, the difference of the charge transfer resistances (ΔRct) of Nyquist plots of the ssDNA probe modified electrode before and after hybridization with miR-106b was obtained and used as an analytical signal. Using the suggested genosensor, it is possible to measure miR-106b in the concentration range of 1.0 fM to 1.0 µM with a detection limit of 0.65 fM under optimal conditions. Moreover, at the genosensor surface, miR-106b can be detected from a non-complementary and a single base mismatch sequence. Also, the genosensor was used to assess miR-106b in a human serum sample and obtained satisfactory results.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Neoplasias Gástricas , Humanos , Biomarcadores Tumorais/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Espectroscopia de Infravermelho com Transformada de Fourier , Técnicas Biossensoriais/métodos , DNA de Cadeia Simples/genética , MicroRNAs/genética , Zinco , Técnicas Eletroquímicas/métodos , Limite de Detecção
3.
Environ Sci Technol ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39324746

RESUMO

Emissions of volatile organic compounds (VOCs) threaten both the environment and human health. To realize the elimination of VOCs, Ru/CeO2 catalysts have been intensively investigated and applied. Although it has been widely acknowledged that the catalytic performance of platinum group metal catalysts was highly determined by their dispersion and coordination environment, the most reactive structures on Ru/CeO2 catalysts for VOCs oxidation are still ambiguous. In this work, starting from Ce-BTC (BTC = 1,3,5-benzenetricarboxylic acid) materials, atomically dispersed Ru catalysts and agglomerated Ru catalysts were successfully created via one-step hydrothermal method (Ru-CeO2-BTC) and conventional incipient wetness impregnation method (Ru/CeO2-BTC), respectively. In a typical model reaction of C3H6 oxidation, atomically dispersed Ruδ+ species with the formation of abundant Ru-O-Ce linkages on Ru-CeO2-BTC were found to perform much better than agglomerated RuOx species on Ru/CeO2-BTC. Further characterizations and mechanism study disclosed that Ru-CeO2-BTC catalyst with atomically dispersed Ru ions and more superior low temperature redox performance compared to Ru/CeO2-BTC could better facilitate the adsorption/activation of C3H6 and the decomposition/desorption of intermediates, thus exhibiting superior C3H6 oxidation activity. This work elucidated the reactive sites on Ru/CeO2 catalysts in the C3H6 oxidation reaction and provided insightful guidance for designing efficient Ru/CeO2 catalysts to eliminate VOCs.

4.
Future Oncol ; 20(16): 1069-1077, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38214149

RESUMO

Mouse double minute 2 homolog (MDM2) is a key negative regulator of the tumor suppressor p53. Blocking the MDM2-p53 interaction, and restoring p53 function, is therefore a potential therapeutic strategy in MDM2-amplified, TP53 wild-type tumors. MDM2 is amplified in several tumor types, including biliary tract cancer (BTC), pancreatic ductal adenocarcinoma (PDAC), lung adenocarcinoma and bladder cancer, all of which have limited treatment options and poor patient outcomes. Brigimadlin (BI 907828) is a highly potent MDM2-p53 antagonist that has shown promising activity in preclinical and early-phase clinical studies. This manuscript describes the rationale and design of an ongoing phase IIa/IIb Brightline-2 trial evaluating brigimadlin as second-line treatment for patients with advanced/metastatic BTC, PDAC, lung adenocarcinoma, or bladder cancer.


Brightline-2: a phase IIa/IIb trial of brigimadlin (BI 907828) in advanced BTC, PDAC, or other solid tumorsIn some types of cancer, including cancers of the bile duct, pancreas, bladder and lung, the number of copies of a gene called MDM2 is abnormally increased (MDM2 amplification). MDM2 usually regulates p53, a protein that stops cancer cells from growing uncontrollably. When MDM2 is amplified, the cell makes too much of the MDM2 protein, which prevents p53 from stopping cancer growth. Blocking the interaction between MDM2 and p53 may allow p53 to do its job again and stop cancer cells from growing.Brightline-2 is a clinical trial that is currently in progress. This trial is assessing the efficacy and safety of an investigational drug, brigimadlin (or BI 907828), in patients with selected advanced or metastatic cancers. To be included, patients must have advanced biliary tract cancer, pancreatic ductal adenocarcinoma, bladder cancer, or lung adenocarcinoma. The tumor must show amplification of MDM2 when tested by a laboratory. Patients will take a 45 mg tablet of brigimadlin by mouth, once every 3 weeks. In this trial, researchers are investigating the ability of the drug to shrink tumors, the side effects of the drug, and the impact of the drug on a patients' quality of life.The goal of this trial is to assess the potential of brigimadlin as a new treatment option for patients with advanced biliary tract cancer, pancreatic ductal adenocarcinoma, bladder cancer, or lung adenocarcinoma.Clinical Trial Registration: NCT05512377 (ClinicalTrials.gov).


Assuntos
Neoplasias do Sistema Biliar , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Proteína Supressora de Tumor p53 , Feminino , Humanos , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/mortalidade , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/mortalidade
5.
Environ Res ; 249: 118473, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354892

RESUMO

The development of a catalyst with a consistent and clearly defined crystal structure is crucial for establishing an efficient catalytic performance system. This study focuses on catalyzing the reduction of nitroarenes to amino-derivatives in an aquatic environment at ambient temperature, employing metallic (Au) and bimetallic (Au-Pd or Au-Ag) nanoparticles loaded on a Ce-BTC metal-organic framework using a facile sol-immobilization approach. Diverse analytical instruments, comprising SEM, TEM, XRD, FT-IR, XPS, TGA, and N2 isotherm, have been utilized to characterize the synthesized catalysts. Among the catalysts that were fabricated, Au-Pd@Ce-BTC displayed the maximum catalytic efficacy, offering a rate constant (kapp) of 0.5841 min-1, conversion percentages reaching 99.7%, and a KAF of 116.8 min-1g-1. Moreover, it exhibited remarkable recyclability over five consecutive cycles. This catalyst offers the advantages of operating under ambient reaction conditions and exhibiting tolerance to a broad range of substrates containing various functional moieties. The mechanistic understanding of nitroarene reduction and the factors contributing to the superior activity of Au-Pd/Ce-BTC are explored through spectroscopic and porosity analyses. Spectroscopic measurements indicate that the elevated Auo and Pdo/Pd2+ ratio, increased surface area, and the synergistic collaboration of the bimetallic NPs are key factors contributing to the heightened activity of Au-Pd/Ce-BTC. These findings hold significant appeal from both an industrial and academic standpoint.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Catálise , Ouro/química , Estruturas Metalorgânicas/química , Oxirredução , Paládio/química , Cério/química , Poluentes Químicos da Água/química
6.
Environ Res ; 256: 119229, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38797465

RESUMO

There has been significant attention on the efficient degradation of pollutants in wastewater using metal-organic frameworks (MOFs) photocatalytic methods over the past decade. Herein, we examined the elimination of two different types of water-contaminating dyes, specifically cationic dye methylene blue (MB) and anionic dye methyl orange (MO), through the application of bimetal Cu/Ni-BTC@SiO2 MOF as high performance photocatalyst. The bimetal Cu/Ni-BTC@SiO2 photocatalyst was synthesized and characterized by XRD, FTIR, SEM, TEM, TGA, BET, DRS, and VSM techniques. The examination of the impact of different operational factors on the elimination of pollutants involved a comprehensive analysis of variables including the photocatalyst type, initial pollutant concentration, quantity of photocatalyst, and pH levels. The highest removal efficiency for MO and MB dyes by the photocatalyst was found to be 98 and 71%, respectively, within 60 min. In the fifth reaction stage, degradation efficiency for MO and MB was 76 and 56% respectively. Kinetic investigations demonstrated that, in the context of the uptake of MB and MO dyes, the interparticle diffusion, and pseudo-second-order models emerged as possessing the most robust correlation coefficients with the experimental data, registering values of 0.988 and 0.961, respectively. The examination of isotherms reveals that the isotherm models proposed by BET, and Anderson (V) demonstrate the highest level of conformity with the empirical data for the decomposition of MB and MO dyes, correspondingly. The TOC levels decreased significantly from 51 to 14 and 47 to 3 mg/L for MB and MO dyes, indicating the effective mineralization process using Cu/Ni-BTC@SiO2.


Assuntos
Cobre , Azul de Metileno , Dióxido de Silício , Poluentes Químicos da Água , Cobre/química , Cobre/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Dióxido de Silício/química , Azul de Metileno/química , Compostos Azo/química , Corantes/química , Níquel/química , Níquel/análise , Catálise , Cinética
7.
Molecules ; 29(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38731608

RESUMO

In this paper, Cu-BTC derived mesoporous CuS nanomaterial (m-CuS) was synthesized via a two-step process involving carbonization and sulfidation of Cu-BTC for colorimetric glutathione detection. The Cu-BTC was constructed by 1,3,5-benzenetri-carboxylic acid (H3BTC) and Cu2+ ions. The obtained m-CuS showed a large specific surface area (55.751 m2/g), pore volume (0.153 cm3/g), and pore diameter (15.380 nm). In addition, the synthesized m-CuS exhibited high peroxidase-like activity and could catalyze oxidation of the colorless substrate 3,3',5,5'-tetramethylbenzidine to a blue product. Peroxidase-like activity mechanism studies using terephthalic acid as a fluorescent probe proved that m-CuS assists H2O2 decomposition to reactive oxygen species, which are responsible for TMB oxidation. However, the catalytic activity of m-CuS for the oxidation of TMB by H2O2 could be potently inhibited in the presence of glutathione. Based on this phenomenon, the colorimetric detection of glutathione was demonstrated with good selectivity and high sensitivity. The linear range was 1-20 µM and 20-300 µM with a detection limit of 0.1 µM. The m-CuS showing good stability and robust peroxidase catalytic activity was applied for the detection of glutathione in human urine samples.


Assuntos
Colorimetria , Cobre , Glutationa , Peróxido de Hidrogênio , Nanoestruturas , Glutationa/análise , Glutationa/química , Colorimetria/métodos , Cobre/química , Nanoestruturas/química , Catálise , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Porosidade , Oxirredução , Ácidos Ftálicos/química , Humanos , Benzidinas/química , Limite de Detecção
8.
J Environ Sci (China) ; 138: 482-495, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135414

RESUMO

In this work, the phosphomolybdate (HPMo) modification strategy was applied to improve the N2 selectivity of MnCo-BTC@SiO2 catalyst for the selective catalytic reduction of NOx, and further, the mechanism of HPMo modification on enhanced catalytic performance was explored. Among MnCo-BTC@SiO2-x catalysts with different HPMo concentrations, MnCo-BTC@SiO2-0.75 catalyst exhibited not only the highest NH3-SCR performance (∼95% at 200-300°C) but also the best N2 selectivity (exceed 80% at 100-300°C) due to the appropriate redox capacity, greater surface acidity. X-ray photoelectron spectrometer (XPS) and temperature programmed reduction of H2 (H2-TPR) results showed that the modification with HPMo reduced the oxidation-reduction performance of the catalyst due to electron transfer from Mo5+ to Mn4+/Mn3+ and prevent the excessive oxidation of ammonia adsorption species. NH3 temperature-programmed desorption of (NH3-TPD) results showed that the modification with HPMo could significantly improve the surface acidity and NH3 adsorption, which enhance the catalytic activity and N2 selectivity. In-situ diffused reflectance infrared Fourier transform spectroscopy (in-situ DRIFTS) revealed that modification with HPMo increased significantly the amount of adsorbed NH3 species on the Bronsted acid site and CB/CL, it suppressed the production of N2O by inhibiting the production of NH species, the deep dehydrogenation of ammonia adsorption species. This study provided a simple design strategy for the catalyst to improve the low-temperature catalytic performance and N2 selectivity.


Assuntos
Amônia , Dióxido de Silício , Amônia/química , Oxirredução , Temperatura , Temperatura Baixa , Catálise
9.
J Fluoresc ; 33(2): 613-629, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36469207

RESUMO

A facile bottom up synthesis technique is opted for the preparation of novel composite SnO2@Zn-BTC. This synthesized composite is fully characterized by Fourier Transform Infrared (FTIR) Spectroscopy, Powder X-Ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS), and Elemental mapping techniques. Optical analysis was performed using UV-Visible absorption spectroscopy and fluorescence studies. Further this composite was utilized for the first time as a photocatalyst for methylene blue (MB) dye degradation under sunlight irradiation. This photocatalyst shows degradation efficiency of 89% within 100 min of exposure of sunlight. In addition to that, the synthesized composite can be utilized as a fluorescence probe for detection of NACs via 'turn-off" quenching response. This composite is extremely sensitive towards 3-NA in aqueous medium with quenching efficiency of 75.42%, which is highest quenching rate till reported. There occurs no interference for detecting 3-NA in the presence of other NACs. The linear fitting of the Stern-Volmer plot for 3-NA shows large quenching constant (KSV) of 0.0115 ppb-1 with correlation coefficient R2 = 0.9943 proves higher sensitivity of composite in sensing process. The outstanding sensitivity of composite for 3-NA is certified by the low detection limit (LOD) of 25 ppb (0.18 µM). Photoinduced Electron Transfer (PET) and Fluorescence Resonance Energy Transfer (FRET) are the mechanisms used for clarification of quenching response of PL intensity by NACs via density functional theory (DFT) calculations and extent spectral overlap, respectively. Hence, synthesized composite is verified as multi-component system to act as excellent photocatalyst as well as fluorescent sensor.

10.
Environ Res ; 237(Pt 2): 117023, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657601

RESUMO

Erythromycin, a commonly used macrolide antibiotic, plays a crucial role in both human medicine and animal husbandry. However, its abuse has led to residual presence in the environment, with problems such as the emergence of resistant bacteria and enrichment of resistance genes. These issues pose significant risks to human health. Thus far, there are no effective, environmentally friendly methods to manage this problem. Enzymes can specifically degrade erythromycin without causing other problems, but their unrecyclability and environmental vulnerability hinder large-scale application. Enzyme immobilization may help to solve these problems. This study used Cu-BTC, a synthetic metal-organic framework, to immobilize the erythromycin-degrading enzyme EreB. The loading temperature and enzyme quantity were optimized. The Cu-BTC and EreB@Cu-BTC were characterized by various methods to confirm the preparation of Cu-BTC and immobilization of EreB. The maximum enzyme loading capacity was 66.5 mg g-1. In terms of enzymatic properties, immobilized EreB had improved heat (25-45 °C) and alkaline (6.5-10) tolerance, along with greater affinity between the enzyme and its substrate; Km decreased from 438.49 to 372.30 mM. Recycling was also achieved; after 10 cycles, 57.12% of the enzyme activity was maintained. After composite degradation, the antibacterial activity of erythromycin-containing wastewater was examined; the results showed that the novel composite could completely inactivate erythromycin. In summary, Cu-BTC was an ideal carrier for immobilization of the enzyme EreB, and the EreB@Cu-BTC composite has good prospects for the treatment of erythromycin-containing wastewater.

11.
Molecules ; 28(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37375292

RESUMO

CNTs/Fe-BTC composite materials were synthesized with the one-step solvothermal method. MWCNTs and SWCNTs were incorporated in situ during synthesis. The composite materials were characterized by different analytical techniques and used in the CO2-photocatalytic reduction to value-added products and clean fuels. In the incorporation of CNTs into Fe-BTC, better physical-chemical and optical properties were observed compared to Fe-BTC pristine. SEM images showed that CNTs were incorporated into the porous structure of Fe-BTC, indicating the synergy between them. Fe-BTC pristine showed to be selective to ethanol and methanol; although, it was more selective to ethanol. However, the incorporation of small amounts of CNTs into Fe-BTC not only showed higher production rates but changes in the selectivity compared with the Fe-BTC pristine were also observed. It is important to mention that the incorporation of CNTs into MOF Fe-BTC allowed for increasing the mobility of electrons, decreasing the recombination of charge carriers (electron/hole), and increasing the photocatalytic activity. In both reaction systems (batch and continuous), composite materials showed to be selective towards methanol and ethanol; however, in the continuous system, lower production rates were observed due to the decrease in the residence time compared to the batch system. Therefore, these composite materials are very promising systems to convert CO2 to clean fuels that could replace fossil fuels soon.

12.
Molecules ; 28(14)2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37513315

RESUMO

With the growing population, industrialization, and agriculture, water contamination not only affects people but entire ecosystems. Metal-organic frameworks (MOFs), because of their large surface area and porosity, show great potential as adsorbents for removing pollutants, such as heavy metals, from contaminated water. The current research aims at examining copper (II) benzene-1,3,5-tricarboxylate (Cu-BTC) MOFs and understanding the mechanism for their adsorption of Pb(II) from aqueous solution. The Cu-BTC samples were characterized using FTIR and XRD, and their surface area and porosity were determined based on N2 adsorption isotherms. The concentration of Pb(II) in the solutions was measured using atomic absorption spectroscopy (AAS). Both kinetic and equilibrium adsorption data were collected and then analyzed using numerical models. The analyses led to the findings that the limiting steps in the adsorption of Pb(II) on Cu-BTC are (a) pore diffusion of Pb(II) and (b) the availability of the active sites on Cu-BTC MOFs. It was further revealed that the former step is more dominant in the adsorption of Pb(II) when the lead concentration is low. The latter step, which is directly proportional to the surface areas of the MOFs, affects the adsorption to a greater extent when the lead concentration is high. The results also show that adsorption of Pb(II) ions on Cu-BTC is mainly a multi-layer heterogeneous process.

13.
Molecules ; 28(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36985688

RESUMO

Gas-phase infiltration of the carbonylchloridogold(I), Au(CO)Cl precursor into the pores of HKUST-1 ([Cu3(BTC)2(H2O)2], Cu-BTC) SURMOFs (surface-mounted metal-organic frameworks; BTC = benzene-1,3,5-tricarboxylate) leads to Au(CO)Cl decomposition within the MOF through hydrolysis with the aqua ligands on Cu. Small Aux clusters with an average atom number of x ≈ 5 are formed in the medium-sized pores of the HKUST-1 matrix. These gold nanoclusters are homogeneously distributed and crystallographically ordered, which was supported by simulations of the powder X-ray diffractometric characterization. Aux@HKUST-1 was further characterized by scanning electron microscopy (SEM) and infrared reflection absorption (IRRA) as well as Raman spectroscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectroscopy (ICP-OES).

14.
Dev Dyn ; 251(1): 75-94, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34773433

RESUMO

BACKGROUND: Progressive maturation of growth plate chondrocytes drives long bone growth during endochondral ossification. Signals from the epidermal growth factor receptor (EGFR), and from bone morphogenetic protein-2 (BMP2), are required for normal chondrocyte maturation. Here, we investigated cross-talk between EGFR and BMP2 signals in developing and adult growth plates. RESULTS: Using in vivo mouse models of conditional cartilage-targeted EGFR or BMP2 loss, we show that canonical BMP signal activation is increased in the hypertrophic chondrocytes of EGFR-deficient growth plates; whereas EGFR signal activation is increased in the reserve, prehypertrophic and hypertrophic chondrocytes of BMP2-deficient growth plates. EGFR-deficient chondrocytes displayed increased BMP signal activation in vitro, accompanied by increased expression of IHH, COL10A1, and RUNX2. Hypertrophic differentiation and BMP signal activation were suppressed in normal chondrocyte cultures treated with the EGFR ligand betacellulin, effects that were partially blocked by simultaneous treatment with BMP2 or a chemical EGFR antagonist. CONCLUSIONS: Cross-talk between EGFR and BMP2 signals occurs during chondrocyte maturation. In the reserve and prehypertrophic zones, BMP2 signals unilaterally suppress EGFR activity; in the hypertrophic zone, EGFR and BMP2 signals repress each other. This cross-talk may play a role in regulating chondrocyte maturation in developing and adult growth plates.


Assuntos
Proteína Morfogenética Óssea 2 , Condrócitos , Receptores ErbB , Osteogênese , Animais , Proteína Morfogenética Óssea 2/metabolismo , Diferenciação Celular , Condrócitos/metabolismo , Condrogênese , Receptores ErbB/metabolismo , Lâmina de Crescimento , Camundongos
15.
Environ Monit Assess ; 195(9): 1056, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37592149

RESUMO

The recovery of organophosphate pesticides (OPPs) from aqueous solutions is imperative considering their agricultural and environmental implications. Among various mitigation approaches used for OPPs' removal, adsorption offers many advantageous features for OPPs abatement owing to its benign nature, cost-effective processing, and non-requirement of excessive equipment. This research describes the adsorptive removal of three organophosphate pesticides (OPPs) namely chlorpyrifos (CPF), methyl parathion (MP), and malathion (MAL) by HKUST-1 (HKUST = Hong Kong University of Science and Technology) metal-organic framework (MOF). The synthesis of HKUST-1 MOFs was confirmed by various spectroscopic and microscopic techniques. The adsorption kinetics was systematically investigated by varying three parameters to include solution pH, contact time, and initial pesticide concentration. Among all the three pesticides, HKUST-1 showed enhanced removal of CPF in terms of pH, resulting in an adsorption capacity of 1.82 mg·g-1. However, under the effect of contact time at 60 min, the adsorption capacity of HKUST-1 for PM, MAL, and CPF were computed to be 1.83, 1.79, and 0.44 mg·g-1, respectively. Besides, HKUST-1 showed a remarkable performance towards adsorptive removal of MAL (14.01 mg·g-1 at 10 mg·L-1 concentration) with linear increase in adsorption capacity as the function of initial pesticide concentration. The MOFs were also able to retain ca. 50% of their adsorption efficiency over the course of five cycles of adsorptive removal of CP. In the future, a comprehensive data table showing the performance of various MOFs against various OPPs can be constructed on the basis of parameters used in this study.


Assuntos
Clorpirifos , Inseticidas , Estruturas Metalorgânicas , Praguicidas , Adsorção , Monitoramento Ambiental , Malation , Compostos Organofosforados
16.
Medicina (Kaunas) ; 59(2)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36837499

RESUMO

Background and Objectives: Metformin has been found to potentially reduce the risk and improve the prognosis of a variety of tumors, but these findings remain controversial in biliary tract cancer (BTC). Therefore, this systematic review and meta-analysis was conducted to investigate the association between metformin and BTC. Materials and Methods: Two independent researchers comprehensively searched PubMed, Embase, the Cochrane Library, and Web of Science for eligible studies published from their inception to 31 March 2022. Comparisons of risk, overall survival (OS), and disease-free survival (DFS) for patients with BTC were selected as the endpoints of interest and pooled by random or fixed-effects models. Results: Eleven studies with a total of 24,788,738 participants were eligible for this analysis. The overall pooled effects showed no significant differences in biliary tract cancer risk (hazard ratio (HR) = 0.82, 95% confidence interval (CI): 0.50-1.35, p = 0.436), OS (HR = 0.88, 95% CI: 0.74-1.04, p = 0.135), or DFS (HR = 1.03, 95% CI: 0.79-1.34, p = 0.829) between metformin users and non-users. When restricting participants to those with diabetes, a similar negative result was found, demonstrating that metformin use was not significantly associated with a lower risk of developing BTC compared with a lack of metformin use (HR = 0.65, 95% CI: 0.39-1.07, p = 0.089); notably, the included studies exhibited significant heterogeneity in the selection of participants and the definition of metformin users. Conclusions: Metformin may not be able to reduce the risk of BTC and improve prognosis in certain populations. Based on the limited quantity and quality of the included studies, the present results should be interpreted within their limitations, and further studies are warranted to determine the optimal timing, dose, duration, and scenario of metformin administration.


Assuntos
Neoplasias do Sistema Biliar , Diabetes Mellitus , Metformina , Humanos , Hipoglicemiantes , Prognóstico , Neoplasias do Sistema Biliar/patologia
17.
Contemp Oncol (Pozn) ; 27(2): 65-70, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37794990

RESUMO

Introduction: The geriatric nutritional risk index (GNRI) is an index of nutritional status associated with clinical outcomes in various cancers; however, its prognostic value in biliary tract cancer (BTC) remains to be elucidated. This retrospective study aimed to investigate the association between preoperative GNRI and long-term prognosis of patients with BTC undergoing surgical resection. Material and methods: A total of 213 patients were included. The relationships between GNRI and clinicopathological variables, including inflammatory markers such as C-reactive protein (CRP) and neutrophil-to-lympho-cyte ratio, were analysed. The impact of GNRI on overall survival (OS) and relapse-free survival (RFS) was investigated by Kaplan-Meier curves and Cox proportional hazards models. Results: Applying a GNRI cut-off of 98, the low-GNRI group comprised 135 patients (63%). The low-GNRI group had elevated carbohydrate antigen 19-9 and CRP levels, high rates of preoperative biliary stenting, lymph node metastases, and perineural invasion, and a lower rate of R0 resection than the high-GNRI group. Both OS and RFS in the low-GNRI group were significantly lower. In multivariate analysis, low GNRI was a significant predictor of poor OS (hazard ratio [HR], 1.731; 95% CI: 1.111-2.696; p = 0.015) and RFS (HR, 1.900; 95% CI: 1.231-2.931; p = 0.004), independently of inflammatory and tumour markers, as well as of pathological features. Conclusions: Preoperative GNRI may be an easily accessible predictor of poor prognosis in patients with BTC undergoing surgical resection.

18.
BMC Plant Biol ; 22(1): 544, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36434510

RESUMO

Calcareous soil contains many problems such as the lack of sources of major and minor elements that are useful for plant growth and development. Plant extracts and nanoparticles are very popular as biostimulants in plant production. Here, the effect of aqueous, non-aqueous and alcoholic oat extracts on the growth, biochemical response of oats leaves and grains grown in experimental fields under new reclamation lands were studied. Moreover, different oat extracts were a pathway through the copper-dependent metal-organic framework (MOFs) to separate bioactive molecules from extracts such as salicylic acid, anthraquinone, and triacylglycerol. Additionally, the separated molecules incorporated in Cu-BTC MOFs and oats extracts missed active molecules were spray applied on oat plants. The results showed that the treated plants showed stimulatory responses in growth and physiology. The treatments improved plant growth and biomass, enhanced total protein, water-soluble carbohydrates, free phenolic compounds content in oat leaves, photosynthesis, and chlorophyll contents. The treatments also improved the level of vitamins E and K, phenolic compounds, and avenanthramides C in the oat grains. Moreover, the treatments showed an improvement in the yield of oats (grain and straw) using water and alcoholic oat extracts in which the active molecules were missed. Our findings demonstrate that Cu-BTC and oats extracts can act as a biostimulant to enhance the biological and chemical properties of oats and increase the yield in calcareous soils. The cytotoxicity study of oats (produced from AE, c@Cu-BTC, and AE-c treatments) was conducted using Vero Cell lines. The anticancer activities of different oat grains were carried out using MCF 7cell lines. The results show that the grains produced from the AE, c@Cu-BTC, and AE-c treatments possessed 94.3, 72.3, and 100% activity towards the cancer cell line. Removal of growth inhibitors from spray solutions increases grain yield and anticancer activity.


Assuntos
Avena , Solo , Avena/metabolismo , Solo/química , Grão Comestível/química , Sementes , Fenóis/metabolismo
19.
J Biol Inorg Chem ; 27(1): 81-87, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34716792

RESUMO

Antibacterial materials are an essential part of modern life and many efforts have been made to find a new and effective type of them. In this study, chlorhexidine (CHX) was loaded on Cu-BTC metal-organic framework (MOF), that both of them are known to have antibacterial properties. The antibacterial properties of Cu-BTC, CHX and CHX@Cu-BTC were investigated against Gram-positive and Gram-negative bacteria. Agar well-diffusion method and MIC test showed that CHX@Cu-BTC has high antibacterial activity. Characterization methods, such as FT-IR, XRD, N2 adsorption-desorption isotherm, TGA, SEM, EDX, TEM and zeta potential, were employed to characterize their structures. Cu-BTC MOF nanoparticles were synthesized and used as nanoporous carriers for chlorhexidine. The loading was about 10%, which was absorbed into the pores. Antibacterial activity was investigated against Gram-negative and Gram-positive bacteria by Agar well diffusion method and MIC (minimal inhibitory concentration) assay. The CHX@Cu-BTC had synergistic antibacterial activity of Cu-BTC and chlorhexidine.


Assuntos
Estruturas Metalorgânicas , Nanoporos , Antibacterianos/química , Antibacterianos/farmacologia , Clorexidina/farmacologia , Cobre/química , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Anal Bioanal Chem ; 414(17): 4809-4819, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35583681

RESUMO

Fractionation of essential oils is technically challenging due to enormous scaffold diversities and structural complexities as well as difficulties in the implementation of the fractionation in the gas phase. Packing beads with multi-dimensional hierarchical nanostructures have been developed herein to pack fractional columns for atmospheric distillations. Activated alumina beads were coated with a porous TiO2 thin film. Growth of Cu-BTC (benzene-1,3,5-tricarboxylate) crystals in resultant porous surfaces leads to the generation of new nanopores and increased metal centers for differential coordination with diverse components of essential oils. The TiO2 thin film is not only an integral part of the composites but also induces the oriented growth of Cu-BTC metal organic framework (MOF) crystals through coordinative interactions. These Al2O3@TiO2@Cu-BTC MOF beads show very strong absorptive capability for major components of essential oils, except for a single cyclic ether eucalyptol with steric hindrances. The eucalyptol was fractionated by using the column packed with those modified alumina beads from raw materials of Artemisia argyi, and Rosmarinus officinalis with high purities up to 96% and 93%, respectively.


Assuntos
Estruturas Metalorgânicas , Óleos Voláteis , Óxido de Alumínio , Eucaliptol , Estruturas Metalorgânicas/química , Óleos de Plantas , Porosidade , Titânio
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