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1.
Small ; : e2311129, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38319033

RESUMEN

Constructing concentration differences between anions and cations at the ends of an ionic conductor is an effective strategy in electricity generation for powering wearable devices. Temperature gradient or salinity gradient is the driving force behind such devices. But their corresponding power generation devices are greatly limited in actual application due to their complex structure and harsh application conditions. In this study, a novel ionic concentration gradient electric generator based on the evaporation difference of the electrolyte is proposed. The device can be constructed without the need for semipermeable membranes, and operation does not need to build a temperature difference. As a demonstration, a PVA-Na ionic hydrogel is prepared as an electrolyte for the device and achieved a thermovoltage of more than 200 mV and an energy density of 77.94 J m-2 at 323 K. Besides, the device exhibits the capability to sustain a continuous voltage output for a duration exceeding 1500 min, as well as enabling charging and discharging cycles for 100 iterations. For practical applications, a module comprising 16 sub-cells is constructed and successfully utilized to directly power a light-emitting diode. Wearable devices and their corresponding cell modules are also developed to recycle body heat.

2.
Nano Lett ; 24(9): 2912-2920, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38391386

RESUMEN

Nanozymes with peroxidase-like activity have been extensively studied for colorimetric biosensing. However, their catalytic activity and specificity still lag far behind those of natural enzymes, which significantly affects the accuracy and sensitivity of colorimetric biosensing. To address this issue, we design PdSn nanozymes with selectively enhanced peroxidase-like activity, which improves the sensitivity and accuracy of a colorimetric immunoassay. The peroxidase-like activity of PdSn nanozymes is significantly higher than that of Pd nanozymes. Theoretical calculations reveal that the p-d orbital hybridization of Pd and Sn not only results in an upward shift of the d-band center to enhance hydrogen peroxide (H2O2) adsorption but also regulates the O-O bonding strength of H2O2 to achieve selective H2O2 activation. Ultimately, the nanozyme-linked immunosorbent assay has been successfully developed to sensitively and accurately detect the prostate-specific antigen (PSA), achieving a low detection limit of 1.696 pg mL-1. This work demonstrates a promising approach for detecting PSA in a clinical diagnosis.


Asunto(s)
Técnicas Biosensibles , Peróxido de Hidrógeno , Masculino , Humanos , Antígeno Prostático Específico , Inmunoensayo/métodos , Antioxidantes , Peroxidasas , Colorimetría/métodos , Técnicas Biosensibles/métodos
3.
J AOAC Int ; 107(3): 471-478, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38407384

RESUMEN

BACKGROUND: For pathogen detection in food, there are occasions where samples cannot be processed immediately after selective enrichment or need to be reexamined days or weeks later for confirmation or retest. OBJECTIVE: This study aimed to investigate the effect of different prolonged period of storage of selective enrichments of food at 4 ± 2°C and room temperature (20-22°C) on the detection and isolation of Salmonella. METHOD: This study included two experiments involving 34 types of foods to compare the effect of 4 ± 2°C and room temperature storage on the detection of Salmonella in 204 selective enrichments (Rappaport-Vassiliadis [RV] and Tetrathionate [TT] broths) during a 42-day storage (Experiment I); and to monitor the survival of Salmonella in 300 selective enrichments (RV and TT) with different pre-enrichment broths (Lactose broth [LB] or Buffered peptone water broth [BPW]), stored at 4°C for 60 days (Experiment II). All the samples were subjected to Salmonella analysis following the FDA BAM method. RESULTS: During multiple samplings, the positive detection rate for Salmonella remained consistent through Day 42 after selective enrichment, irrespective of Salmonella serotype, storage temperature, pre-enrichment broth, or selective enrichment broth in both Experiment I and II. However, on Day 60 sampling in Experiment II, seven previously positive results turned to negatives. These data indicated that storage of RV and TT enrichments at 4 ± 2°C or room temperature for up to 42 days after selective enrichment did not compromise the detection of Salmonella in the tested food categories, regardless of Salmonella serotypes and the broths used for pre-enrichment and selective enrichment. CONCLUSIONS: At least for the food types studied in this experiment, the recovery of Salmonella from selective enrichments could be postponed for a limited period of time (e.g., <42 days) if needed without adversely affecting the test results. However, the delayed analysis of TT and RV enrichments does pose a risk of reduced detection sensitivity, as evidenced by the seven negative results on Day 60 compared to previous positives. We do not recommend or endorse delaying the analysis of TT and RV enrichments. HIGHLIGHTS: In the food matrixes investigated in this experiment, the plating and isolation of Salmonella from selective TT and RV enrichments stored at 4 ± 2°C or room temperature could be deferred for a period (up to 42 days) without any negative effect on the test results, if necessary.


Asunto(s)
Microbiología de Alimentos , Salmonella , Temperatura , Salmonella/aislamiento & purificación , Microbiología de Alimentos/métodos , Factores de Tiempo , Almacenamiento de Alimentos , Contaminación de Alimentos/análisis , Medios de Cultivo
4.
Environ Technol ; 45(10): 2045-2066, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36609215

RESUMEN

We propose a feasible and economical method of constructing biomass-based multifunctional photocatalysts with excellent adsorption performance and high photodegradation abilities toward tetracycline (TC) and methyl blue (MB) under visible light. A series of novel hybrids of porous graphitic carbon embedded with Fe2O3/Fe3O4 nanocrystals (denoted as Fe2O3/Fe3O4@C) were derived from lichen doped with different dosages of Fe3+ by calcination at 700°C under a N2 atmosphere. The Fe2O3/Fe3O4@C hybrids exhibited nanoflake-like shapes, mesoporous structures, and efficient visible light harvesting, thus indicating enhanced adsorption ability and photoactivity toward pollutants. The formed Fe2O3/Fe3O4 heterojunction improved the separation efficiency and inhibited the recombination of photogenerated carriers, whereas the carbon network improved the transfer of photogenerated electrons. Under optimised conditions, the Fe2O3/Fe3O4@C-1 hybrid demonstrated enhanced photodegradation efficiencies of 96.4% for TC and 100% for MB under visible light. In addition, electron spin resonance and trapping measurements were performed to identify active species and determine the photocatalytic mechanism toward pollutants. •O2- and •OH were the active species involved, playing critical roles in the TC and MB photodegradation processes. In addition, a bacterium test revealed that the products of TC degradation by Fe2O3/Fe3O4@C-1 showed low biological toxicity. This work provides a promising preparation strategy or biomass-based photocatalysts for application in environmental pollutant treatment.


Asunto(s)
Bencenosulfonatos , Contaminantes Ambientales , Grafito , Líquenes , Nanopartículas , Carbono , Fotólisis , Antibacterianos , Tetraciclina/química , Grafito/química , Luz , Catálisis
5.
Small ; 20(5): e2306637, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37759387

RESUMEN

Selective hydrogenation of nitrostyrenes is a great challenge due to the competitive activation of the nitro groups (─NO2 ) and carbon-carbon (C═C) double bonds. Photocatalysis has emerged as an alternative to thermocatalysis for the selective hydrogenation reaction, bypassing the precious metal costs and harsh conditions. Herein, two crystalline phases of layered ternary sulfide Cu2 WS4 , that is, body-centered tetragonal I-Cu2 WS4 nanosheets and primitive tetragonal P-Cu2 WS4 nanoflowers, are controlled synthesized by adjusting the capping agents. Remarkably, these nanostructures show visible-light-driven photocatalytic performance for selective hydrogenation of 3-nitrostyrene under mild conditions. In detail, the I-Cu2 WS4 nanosheets show excellent conversion of 3-nitrostyrene (99.9%) and high selectivity for 3-vinylaniline (98.7%) with the assistance of Na2 S as a hole scavenger. They also can achieve good hydrogenation selectivity to 3-ethylnitrobenzene (88.5%) with conversion as high as 96.3% by using N2 H4 as a proton source. Mechanism studies reveal that the photogenerated electrons and in situ generated protons from water participate in the former hydrogenation pathway, while the latter requires the photogenerated holes and in situ generated reactive oxygen species to activate the N2 H4 to form cis-N2 H2 for further reduction. The present work expands the rational synthesis of ternary sulfide nanostructures and their potential application for solar-energy-driven organic transformations.

6.
Environ Sci Pollut Res Int ; 31(4): 5013-5031, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38147259

RESUMEN

An increasing amount of sewage has been discharged into water bodies in the progression of industrialization and urbanization, causing serious water pollution. Meanwhile, the increase of nutrients in the water induces water eutrophication and rapid growth of algae. Photocatalysis is a common technique for algal inhibition and sterilization. To improve the utilization of visible light and the conversion efficiency of solar energy, more organic photocatalytic materials have been gradually developed. In addition to ultraviolet light, partial infrared light and visible light could also be used by organic photocatalysts compared with inorganic photocatalysts. Simultaneously, organic photocatalysts also exhibit favorable stability. Most organic photocatalysts can maintain a high degradation rate for algae and bacteria after several cycles. There are various organic semiconductors, mainly including small organic molecules, such as perylene diimide (PDI), porphyrin (TCPP), and new carbon materials (fullerene (C60), graphene (GO), and carbon nanotubes (CNT)), and large organic polymers, such as graphite phase carbon nitride (g-C3N4), polypyrrole (PPy), polythiophene (PTH), polyaniline (PANI), and polyimide (PI). In this review, the classification and synthesis methods of organic photocatalytic materials were elucidated. It was demonstrated that the full visible spectral response (400-750 nm) could be stimulated by modifying organic photocatalysts. Moreover, some problems were summarized based on the research status related to algae and bacteria, and corresponding suggestions were also provided for the development of organic photocatalytic materials.


Asunto(s)
Nanotubos de Carbono , Polímeros , Pirroles , Luz , Esterilización , Agua , Catálisis
7.
Bioelectrochemistry ; 156: 108630, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38147788

RESUMEN

In this work, a novel two-dimensional semiconducting metal covalent organic framework (CuTAPc-TFPP-COF) was synthesized and used as biosensing platform to construct aptasensor for trace detection of tetracycline (TC). The CuTAPc-TFPP-COF integrates the highly conjugated structure, large specific surface area, high porosity, abundant nitrogen functional groups, excellent electrochemical activity, and strong bioaffinity for aptamers, providing abundant active sites to effectively anchor aptamer strands. As a result, the CuTAPc-TFPP-COF-based aptasensor shows high sensitivity for detecting TC via specific recognition between aptamer and TC to form Apt-TC complex. An ultralow detection limit of 59.6 fM is deduced from the electrochemical impedance spectroscopy within a wide linear range of 0.1-100000 pM for TC. The CuTAPc-TFPP-COF-based aptasensor also exhibits good selectivity, reproducibility, stability, regenerability, and excellent applicability for real river water, milk, and pork samples. Therefore, the CuTAPc-TFPP-COF-based aptasensor will be promising for detecting trace harmful antibiotics residues in environmental water and food samples.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Isoindoles , Estructuras Metalorgánicas , Compuestos Organometálicos , Porfirinas , Putrescina , Antibacterianos/análisis , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Límite de Detección , Estructuras Metalorgánicas/química , Putrescina/análogos & derivados , Reproducibilidad de los Resultados , Tetraciclina , Agua
8.
J Hazard Mater ; 465: 133273, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38113729

RESUMEN

Photocatalytic technology showed significant potential for addressing the issue of cyanobacterial blooms resulting from eutrophication in bodies of water. However, the traditional powder materials were easy to agglomerate and settle, which led to the decrease of photocatalytic activity. The emergence of floating photocatalyst was important for the practical application of controlling harmful algal blooms. This study was based on the efficient powder photocatalyst bismuth oxide composite copper-metal organic framework (Bi2O3 @Cu-MOF), which was successfully loaded onto melamine sponge (MS) by sodium alginate immobilization to prepare a floating photocatalyst MS/Bi2O3 @Cu-MOF for the inactivation of Microcystis aeruginosa (M. aeruginosa) under visible light. When the capacity was 0.4 g (CA0.4), MS/Bi2O3 @Cu-MOF showed good photocatalytic activity, and the inactivation rate of M. aeruginosa reached 74.462% after 120 h. MS/Bi2O3 @Cu-MOF-CA0.4 showed a large specific surface area of 30.490 m2/g and an average pore size of 22.862 nm, belonging to mesoporous materials. After 120 h of treatment, the content of soluble protein in the MS/Bi2O3 @Cu-MOF-CA0.4 treatment group decreased to 0.365 mg/L, the content of chlorophyll a (chla) was 0.023 mg/L, the content of malondialdehyde (MDA) increased to 3.168 nmol/mgprot, and the contents of various antioxidant enzymes experienced drastic changes, first increasing and then decreasing. The photocatalytic process generated·OH and·O2-, which played key role in inactivating the algae cells. Additionally, the release of Cu2+ and adsorption of the material also contributed to the process.


Asunto(s)
Estructuras Metalorgánicas , Microcystis , Triazinas , Cobre/metabolismo , Microcystis/metabolismo , Estructuras Metalorgánicas/metabolismo , Clorofila A , Seda/metabolismo , Polvos/metabolismo , Bismuto , Floraciones de Algas Nocivas
9.
Anal Chim Acta ; 1283: 341977, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37977794

RESUMEN

Development of highly sensitive and accurate biosensors still faces a great challenge. Herein, glucose oxidase (GOx) is efficiently immobilized on the AuCu hydrogels owing to their porous structure and interfacial interaction, demonstrating enhanced catalytic activity, satisfactory stability and recyclability. Besides, by integration of AuCu@GOx and electrochromic material of Prussian blue, a sensitive and stable biosensing platform based on the excellent electrochromic property of Prussian blue and the enhanced enzyme activity of AuCu@GOx is developed, which enables the electrochemical and visual dual-mode detection of glucose. The as-constructed biosensing platform possesses a wide linear range, and good selectivity for glucose detection with a limit of detection of 0.82 µM in visual mode and 0.84 µM in electrochemical mode. This easy-to-operate biosensing platform opens a door for the practical application of the multi-mode strategy for glucose detection.


Asunto(s)
Técnicas Biosensibles , Glucosa Oxidasa , Glucosa Oxidasa/química , Enzimas Inmovilizadas/química , Glucosa , Ferrocianuros
10.
Angew Chem Int Ed Engl ; 62(50): e202312568, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-37848394

RESUMEN

A synthetic strategy based on biogenetic building blocks for the collective and divergent biomimetic synthesis of cleistoperlones A-F, a cinnamoylphloroglucinol collection discovered from Cleistocalyx operculatus, has been developed. These syntheses proceeded successfully in only six to seven steps starting from commercially available 1,3,5-benzenetriol and involving oxidative activation of stable biogenetic building blocks as a crucial step. Key features of the syntheses include a unique Michael addition/ketalization/1,6-addition/enol-keto tautomerism cascade reaction for the construction of the dihydropyrano[3,2-d]xanthene tetracyclic core of cleistoperlones A and B, and a rare inverse-electron-demand hetero-Diels-Alder cycloaddition for the establishment of benzopyran ring in cleistoperlones D-F. Moreover, cleistoperlone A exhibited significant antiviral activity against acyclovir-resistant strains of herpes simplex virus type 1 (HSV-1/Blue and HSV-1/153).


Asunto(s)
Syzygium , Biomimética , Estereoisomerismo , Reacción de Cicloadición , Antivirales/farmacología
11.
Chemosphere ; 343: 140276, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37758086

RESUMEN

Photocatalytic technology for inactivating harmful algae has shown great research potential, in previous work, a kind of non-noble metal modified TiO2 loading onto copper metal organic framework (SNP-TiO2@Cu-MOF) was proved to show high removal efficiency against Karenia mikimotoi (K. mikimotoi). However, the recovery problem of powdered photocatalysts and its potential ecological hazards were still existed. In order to solve this, this study selected four macro-floating carriers and loaded photocatalyst on their surface. The floating photocatalyst with luffa sponge and expanded perlite as carriers were prepared by hydrothermal synthesis, and the floating photocatalyst with melamine sponge and polyurethane sponge as carriers were prepared by sodium alginate fixation method. The photocatalyst was firmly supported on the carriers, and the octahedral structure of SNP-TiO2@Cu-MOF photocatalyst could be well retained by hydrothermal synthesis. The advantages of sodium alginate fixation method were simple preparation process and low cost. The specific surface area of melamine foam photocatalyst (MF-P) was the highest, 28.47 m2/g, and the algae inactivation rate was also the best, which was 98.68% in 6 h. The MF-P group showed a decrease of 81.8% in soluble protein content and 81.4% in chlorophyll-a content of K. mikimotoi after 1 h of photocatalysis, respectively. The four photocatalysts showed good recyclability, and especially in MF-P group. The inactivation efficiency was still as high as 94.12% after four experiments. The floating photocatalyst would lay the foundation for further application of photocatalytic materials for algae removal.

12.
Nat Commun ; 14(1): 5372, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37666836

RESUMEN

Diazo compounds are rare natural products possessing various biological activities. Kinamycin and lomaiviticin, two diazo natural products featured by the diazobenzofluorene core, exhibit exceptional potency as chemotherapeutic agents. Despite the extensive studies on their biosynthetic gene clusters and the assembly of their polyketide scaffolds, the formation of the characteristic diazo group remains elusive. L-Glutamylhydrazine was recently shown to be the hydrazine donor in kinamycin biosynthesis, however, the mechanism for the installation of the hydrazine group onto the kinamycin scaffold is still unclear. Here we describe an O-methyltransferase-like protein, AlpH, which is responsible for the hydrazine incorporation in kinamycin biosynthesis. AlpH catalyses a unique SAM-independent coupling of L-glutamylhydrazine and polyketide intermediate via a rare Mannich reaction in polyketide biosynthesis. Our discovery expands the catalytic diversity of O-methyltransferase-like enzymes and lays a strong foundation for the discovery and development of novel diazo natural products through genome mining and synthetic biology.


Asunto(s)
Productos Biológicos , Policétidos , Metiltransferasas/genética , Metabolismo Secundario , Catálisis
13.
Small ; 19(42): e2302600, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37322392

RESUMEN

An n-n type heterojunction comprising with CuN and BN dual active sites is synthesized via in situ growth of a conductive metal-organic framework (MOF) [Cu3 (HITP)2 ] (HITP = 2,3,6,7,10,11-hexaiminotriphenylene) on hexagonal boron nitride (h-BN) nanosheets (hereafter denoted as Cu3 (HITP)2 @h-BN) for the electrocatalytic nitrogen reduction reaction (eNRR). The optimized Cu3 (HITP)2 @h-BN shows the outstanding eNRR performance with the NH3 production of 146.2 µg h-1 mgcat -1 and the Faraday efficiency of 42.5% due to high porosity, abundant oxygen vacancies, and CuN/BN dual active sites. The construction of the n-n heterojunction efficiently modulates the state density of active metal sites toward the Fermi level, facilitating the charge transfer at the interface between the catalyst and reactant intermediates. Additionally, the pathway of NH3 production catalyzed by the Cu3 (HITP)2 @h-BN heterojunction is illustrated by in situ FT-IR spectroscopy and density functional theory calculation. This work presents an alternative approach to design advanced electrocatalysts based on conductive MOFs.

14.
J Med Chem ; 66(9): 6082-6104, 2023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37079895

RESUMEN

The prevalence of nonalcoholic steatohepatitis (NASH) is increasing rapidly worldwide, and NASH has become a serious problem for human health. Recently, the selective activation of the intestinal farnesoid X receptor (FXR) was considered as a more promising strategy for the treatment of NASH with lesser side effects due to reduced systemic exposure. Moreover, the inhibition of intestinal fatty acid binding protein 1 (FABP1) alleviated obesity and NASH by reducing dietary fatty acid uptake. In this study, the first-in-class intestinal restricted FXR and FABP1 dual-target modulator ZLY28 was discovered by comprehensive multiparameter optimization studies. The reduced systemic exposure of ZLY28 might provide better safety by decreasing the on- and off-target side effects in vivo. In NASH mice, ZLY28 exerted robust anti-NASH effects by inhibiting FABP1 and activating the FXR-FGF15 signaling pathway in the ileum. With the above attractive efficacy and preliminary safety profiles, ZLY28 is worthy of further evaluation as a novel anti-NASH agent.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Animales , Humanos , Ratones , Proteínas de Unión a Ácidos Grasos , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Obesidad , Receptores Citoplasmáticos y Nucleares/metabolismo
15.
Adv Sci (Weinh) ; 10(8): e2205786, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36683249

RESUMEN

A defect-rich 2D p-n heterojunction, Cox Ni3- x (HITP)2 /BNSs-P (HITP: 2,3,6,7,10,11-hexaiminotriphenylene), is constructed using a semiconductive metal-organic framework (MOF) and boron nanosheets (BNSs) by in situ solution plasma modification. The heterojunction is an effective catalyst for the electrocatalytic nitrogen reduction reaction (eNRR) under ambient conditions. Interface engineering and plasma-assisted defects on the p-n Cox Ni3-x (HITP)2 /BNSs-P heterojunction led to the formation of both Co-N3 and B…O dual-active sites. As a result, Cox Ni3-x (HITP)2 /BNSs-P has a high NH3 yield of 128.26 ± 2.27 µg h-1 mgcat. -1 and a Faradaic efficiency of 52.92 ± 1.83% in 0.1 m HCl solution. The catalytic mechanism for the eNRR is also studied by in situ FTIR spectra and DFT calculations. A Cox Ni3- x (HITP)2 /BNSs-P-based Zn-N2 battery achieved an unprecedented power output with a peak power density of 5.40 mW cm-2 and an energy density of 240 mA h gzn -1 in 0.1 m HCl. This study establishes an efficient strategy for the rational design, using defect and interfacial engineering, of advanced eNRR catalysts for ammonia synthesis under ambient conditions.

16.
J Hazard Mater ; 447: 130815, 2023 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-36669412

RESUMEN

Linoleic acid (LA) shows great potential in inhibiting the growth of multiple red tide microalgae by disturbing algal physio-biochemical processes. However, our knowledge on the mechanisms of algal mortality at metabolic level remains limited. Herein, the response of K. mikimotoi to LA was evaluated using metabolomics, stable isotope techniques (SIT), and physiological indicators. Results showed that 100 µg/L LA promoted the growth of K. mikimotoi, which was significantly inhibited by 500 µg/L LA, along with a significant reduction of photosynthetic pigments and a significant increase of reactive oxygen species (ROS). SIT showed that LA entered algal cells, and 56 isotopologues involved in ferroptosis, carotenoid biosynthesis, and porphyrin metabolism were identified. Non-targeted metabolomics identified 90 and 111 differential metabolites (DEMs) belonging to 11 metabolic pathways under the 500 µg/L and 100 µg/L LA exposure, respectively. Among them, 34 DEMs were detected by SIT. Metabolic pathway analysis showed that 500 µg/L LA significantly promoted ferroptosis, and significantly inhibited carotenoid biosynthesis, porphyrin metabolism, sphingolipid metabolism, and lipopolysaccharide biosynthesis, presenting changes opposite to those observed in 100 µg/L LA-treated K. mikimotoi. Overall, this study revealed the metabolic response of K. mikimotoi to LA, enriching our understanding on the allelochemical mechanism of LA on K. mikimotoi.


Asunto(s)
Dinoflagelados , Porfirinas , Ácido Linoleico/metabolismo , Ácido Linoleico/farmacología , Feromonas/metabolismo , Feromonas/farmacología , Fotosíntesis , Carotenoides/metabolismo
17.
J Hazard Mater ; 442: 130059, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36179626

RESUMEN

In this study, the SNP-TiO2@Cu-MOF composite was prepared successfully by loading non-noble metal modified TiO2 (SNP-TiO2) on the surface of copper metal organic skeleton (Cu-MOF), and compared the inactivation efficiency of different photocatalysts to Karenia mikimotoi (K. mikimotoi) under visible light. The obtained photocatalyst had the characteristic crystal faces of Cu-MOF and SNP- TiO2, and contained functional groups such as Cu-O, -COOH, N-O, P-O, etc., which indicated the structural stability of the photocatalyst. The band gap of SNP-TiO2@Cu-MOF composite was 2.82 eV, and it had great light absorption ability in visible light region. It was proved to be a mesoporous adsorption material, which had a huge specific surface area (245 m2/g). Compared with other photocatalysts, SNP-TiO2@Cu-MOF composite showed the strongest photocatalytic activity. When the concentration of composite material was set to 100 mg/L and the exposure time was 6 h, the visible light photocatalytic inactivation efficiency of K. mikimotoi was 93.75 %. By measuring various metabolic indexes of K. mikimotoi under the action of different photocatalysts for 1 h, it was confirmed that cell inactivation was due to the increased membrane permeability and degradation of photosynthetic pigments and main life proteins. This research showed that SNP-TiO2@Cu-MOF composite material was full of great potential and application prospect in controlling the outbreak of eutrophication.


Asunto(s)
Cobre , Estructuras Metalorgánicas , Cobre/química , Catálisis , Luz
18.
Front Oncol ; 13: 1342289, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38260849

RESUMEN

Objective: This study endeavored to explore the optimal treatment strategy and conduct a prognostic analysis for patients diagnosed with pT4M0 (pathologic stage T4) colon adenocarcinoma (COAD). Methods and materials: A total of 8,843 patients diagnosed with pT4M0 COAD between January 2010 and December 2015 were included in this study from the Surveillance, Epidemiology, and End Results (SEER) database. These patients were randomly divided into a training set and an internal validation set using a 7:3 ratio. Variables that demonstrated statistical significance (P<0.05) in univariate COX regression analysis or held clinical significance were incorporated into the multivariate COX regression model. Subsequently, this model was utilized to formulate a nomogram. The predictive accuracy and discriminability of the nomogram were assessed using the C-index, area under the curve (AUC), and calibration curves. Decision curve analysis (DCA) was conducted to confirm the clinical validity of the model. Results: In the entire SEER cohort, the 3-year overall survival (OS) rate (74.22% vs. 63.20%, P<0.001) and the 3-year cancer-specific survival (CSS) rate (76.25% vs. 66.98%, P<0.001) in the surgery combined with postoperative adjuvant therapy (S+ADT) group surpassed those in the surgery (S) group. Multivariate COX regression analysis of the training set unveiled correlations between age, race, N stage, serum CEA (carcinoembryonic antigen), differentiation, number of resected lymph nodes, and treatment modalities with OS and CSS. Nomograms for OS and CSS were meticulously crafted based on these variables, achieving C-indexes of 0.692 and 0.690 in the training set, respectively. The robust predictive ability of the nomogram was further affirmed through receiver operating characteristic (ROC) and calibration curves in both the training and validation sets. Conclusion: In individuals diagnosed with pT4M0 COAD, the integration of surgery with adjuvant chemoradiotherapy demonstrated a substantial extension of long-term survival. The nomogram, which incorporated key factors such as age, race, differentiation, N stage, serum CEA level, tumor size, and the number of resected lymph nodes, stood as a dependable tool for predicting OS and CSS rates. This predictive model held promise in aiding clinicians by identifying high-risk patients and facilitating the development of personalized treatment plans.

19.
RSC Adv ; 12(50): 32307-32317, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36425679

RESUMEN

A series of robust photocatalysts of mesoporous carbon nanospheres embedded with multiple cobalt active sites (Co/Co x O y @mC) have been constructed for efficient removal and photodegradation of malachite green (MG). Here, a cobalt-based polymeric-metal-organic framework (polyMOF(Co)) was constructed by using a polyether ligand containing 1,4-benzenedicarboxylic acid units. Afterward, polyMOF(Co) was calcined into a series of Co/Co x O y @mC hybrids at diverse high temperatures (400, 600, and 800 °C) under a N2 atmosphere. Therefore, Co coordination centers were transformed into various active sites such as Co, CoO, and Co3O4, which were embedded within the mesoporous carbon network derived from the polymeric skeleton. Considering the even distribution of Co-related active species and high porosity inherited from polyMOF(Co), the constructed Co/Co x O y @mC hybrid obtained at 600 °C illustrated higher removal ability (79%) with a maximum adsorption capacity of 314 mg g-1 within 120 min and better photodegradation performance (degradation rate of 95%) toward MG than those of the other photocatalysts obtained at 400 and 800 °C. Moreover, the possible photocatalytic reaction mechanisms, including the transfer behavior of charge carriers, generation of reactive species, and intermediate degradation of products, were provided. The present work showed an alternative strategy for the feasible and efficient preparation of photocatalysts based on MOFs.

20.
Front Oncol ; 12: 843250, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36387083

RESUMEN

In this study, we aim to investigate the predictive value of serum vascular endothelial growth factor (VEGF) in evaluating treatment efficacy and long-term prognosis for patients with non-surgical esophageal squamous cell carcinoma (ESCC). The patients diagnosed with ESCC by histopathology who didn't receive surgical treatment were retrospectively analyzed. Through follow-up and prognostic analysis, we explored the value of serum VEGF changes before, during, and after radiotherapy for predicting treatment efficacy, and identified important indicators to construct the predictive model. Eighty-four patients were enrolled in this study, and the objective response rate (ORR) after treatment was 75.0%. The serum VEGF before, during and after radiotherapy were 108.2 ± 38.4, 98.6 ± 20.3 and 96.9 ± 20.0pg/ml, respectively. Staging and serum VEGF during radiotherapy were the independent factors affecting the treatment efficacy of non-surgical ESCC patients (OR=0.182 and 0.959, P<0.05). The median overall survival (OS) and progression-free survival (PFS) were 24.4 and 15.8 months. The 3-year, 5-year, 10-year OS rates and PFS rates were 35.7%, 26.2%, 14.4%, and 26.2%, 22.6%, 12.3%, respectively. By performing COX regression analysis, we found that the TNM stage, changes of VEGF after radiotherapy (∆VEGF2), and endoscopic histopathological response were the independent prognostic factors for OS and PFS (P<0.05). The R2 of the constructed prediction model was 0.328 and 0.362, and the C-index was 0.697 and 0.708, respectively. The follow-up time-dependent AUC showed that the predicted AUC was stable and greater than 0.7 as the follow-up time increased. For patients with non-surgical ESCC, those with low VEGF levels during radiotherapy had better treatment efficacy, and those with significant VEGF reduction after radiotherapy had a better prognosis. In summary, our results demonstrate that it is feasible to construct a model to evaluate and predict the efficacy and prognosis of patients with non-surgical ESCC based on serum VEGF measurement.

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