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1.
Huan Jing Ke Xue ; 45(2): 1185-1195, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471955

RESUMO

Microplastics are an emerging contaminant that can persist in the environment for extended periods, posing risks to ecological systems. Recently, microplastic pollution has emerged as a major global environmental problem. In order to ensure accurate and scientific evaluation of the ecological risks associated with microplastic pollution, it is of paramount importance to improve the simplicity and reliability of microplastic identification, systematically analyze the pollution characteristics of microplastics in various environmental media, and clarify their environmental impacts. Machine learning technology has gained widespread attention in microplastic research by learning and analyzing large volumes of data to establish result evaluation or prediction models. The use of machine learning can enhance the automation and identification efficiency of visual and spectral identification of microplastics, provide scientific support for tracing the sources of microplastic pollution, and help reveal the complex environmental effects of microplastics. This review provides a summary of the application characteristics and limitations of machine learning in the aforementioned areas by reviewing the progress made in research that employs machine learning technology in microplastic identification and environmental risk assessment. Furthermore, the findings of the review will provide suggestions and prospects for the development and application of machine learning in related areas.

2.
RSC Adv ; 14(5): 3611-3616, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38264269

RESUMO

Typical small organic dyes exhibit excellent UV absorption capabilities and are commonly used as additives to shield plastic films from photoaging. However, their tendency to decompose easily and migrate rapidly within a polymer matrix limits their service life. Herein we prepared g-C3N4 nanosheets and fabricated g-C3N4/PBAT films to investigate the effects of g-C3N4 on UV shielding and plasticizing of a biodegradable PBAT film. Photophysical characterizations revealed that an improved UV light barrier performance was achieved on g-C3N4/PBAT films compared to pure PBAT. Furthermore, the photoaging results show that g-C3N4 can stably exist in the PBAT matrix, enabling the aged g-C3N4/PBAT films to maintain their effective UV shielding ability, whereas the aged benzophenone (UV-0)/PBAT film shows a substantial decrease in UV light absorption due to the photodecomposition of UV-0. Additionally, g-C3N4 acted as a reinforcing material for PBAT, as evidenced by the approximately 1.5-fold increase in longitudinal tear strength and 1.6-fold increase in tensile strength of g-C3N4/PBAT films compared to pure PBAT. Remarkably, even after 100 hours of photoaging, the aged g-C3N4/PBAT films retained their favorable mechanical properties. This study highlights the potential of g-C3N4 as a new type of UV shield additive for future practical applications in protecting biodegradable plastic from photoaging.

3.
J Colloid Interface Sci ; 650(Pt A): 193-202, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37402325

RESUMO

Solar-driven electrochemical NO3- reduction reaction (NO3-RR) is a clean and sustainable strategy that can convert pollutant NO3- in wastewater to value-added NH3. In recent years, cobalt oxides-based catalysts have shown their intrinsic catalytic properties toward NO3-RR but still have room for improvement through catalyst design. Coupling metal oxides with noble metal has been demonstrated to improve electrochemical catalytic efficiency. Here, we use Au species to tune the surface structure of Co3O4 and improve the efficiency of NO3-RR to NH3. The obtained Au nanocrystals-Co3O4 catalyst exhibited an onset potential of 0.54 V vs RHE, NH3 yield rate of 27.86 µg/h·cm2, and Faradaic efficiency (FE) of 83.1% at 0.437 V vs RHE in an H-cell, which is much higher than Au small species (Au clusters or single atoms)-Co3O4 (15.12 µg/h·cm2) and pure Co3O4 (11.38 µg/h·cm2), respectively. Combined experiments with theory calculations, we attributed the enhanced performance of Au nanocrystals-Co3O4 to the reduced energy barrier of *NO hydrogenation to the *NHO and suppression of HER, which originated from the charge transfer from Au to Co3O4. Using an amorphous silicon triple-junction (a-Si TJ) as the solar cell and an anion exchange membrane electrolyzer (AME), an unassisted solar-driven NO3-RR to NH3 prototype was realized with a yield rate of 4.65 mg/h and FE of 92.1%.

4.
Polymers (Basel) ; 14(7)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35406307

RESUMO

Poly-(butylene adipate-co-terephthalate) (PBAT) has become one of the most prevalent biodegradable plastic film materials owing to its good degradability, mechanical properties, and processability. However, the degradation time of this material was too fast and the functional period was short, which limited its application. Herein, three new tropolone-based UV absorbers (UVA-1C, UVA-4C and UVA-6C) were rationally designed and blended into PBAT. The PBAT/UVA films that formed were used against UV aging and prolonged the functional period of PBAT film. The three new absorbers were synthesized by bridging two tropolones using three different organic chains with different flexibility. Among them, the UVA-6C showed the strongest UV absorbance at around 238 nm and 320 nm. Consequently, the PBAT/UVA-6C film showed an extended validity period of 240 h in the Xenon lamp aging machine and a prolonged functional period of 8 d during the field application test when compared to pure PBAT. More importantly, a 7.8% increase in the maize yield was obtained under PBAT/UVA-6C film relative to pure PBAT film. Obviously, the novel prepared UVA-6C compound is a good candidate for UV absorption in PBAT, which makes PBAT/UVA-6C film more advantageous over pure PBAT in practical applications as biodegradable agricultural film.

5.
Sci Rep ; 11(1): 3366, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33564010

RESUMO

In the present work, Ag@AgCl-reinforced cellulose composites with enhanced antibacterial and photocatalytic degradation properties were successfully synthesized via oil bath heating method. During the process, zinc chloride (ZnCl2) solution was used as both Cl- resource to form AgCl and the solvent to dissolve cellulose. The samples were synthesized with different temperatures, times, and concentrations of ZnCl2 solution. The morphology, microstructure and phase of the as-prepared samples were analyzed with X-ray powder diffraction (XRD), fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), photocatalytic activity studies and inhibition zone experiments. Results showed that dye solution could be completely degraded by the materials in 1 h, and higher concentrations of ZnCl2 solution favored for larger inhibition zones (higher to 10.8 mm). This synthetic strategy displayed here offers more possibilities to high value-added applications of cellulose.

6.
Carbohydr Polym ; 253: 117170, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278964

RESUMO

Microwave-assisted hydrolysis has been widely studied for cellulose fiber isolation, but the influence of reaction conditions and the microwave non-thermal effect are not well clarified. In this study, a series of well-designed experiments were carried out to measure the effects of reaction conditions including temperature, duration and alkali concentration. Compared to the other parameters, temperature was more relevant to the cellulose content in fiber. It could reach the maximum purity of 90.66 % when the temperature was up to 140 °C. Moreover, the existence of non-thermal effect of microwave has been confirmed through extensive determination and characterization of the fibers obtained from parallel controlled experiments conducted with or without microwave assistance. Approximately 50 %-75 % reduction in reaction time or 67 % of that in chemical costs would be realized under microwave with respect to traditional heating hydrolysis. Therefore, this work provides both deep insight and efficiency strategy into the microwave-assisted cellulose isolation.

7.
BMJ Open ; 6(11): e012175, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27852711

RESUMO

INTRODUCTION: Whether adding percutaneous transluminal angioplasty and stenting (PTAS) to background medical treatment is effective for decreasing the incidence of stroke or death in patients with symptomatic intracranial atherosclerosis (ICAS) is still controversial. We perform a randomised controlled trial to examine the effectiveness and safety of an improved PTAS procedure for patients with ICAS. METHODS AND ANALYSIS: A randomised controlled trial will be conducted in three hospitals in China. Eligible patients with ICAS will be randomly assigned to receive medication treatment (MT) plus PTAS or MT alone. The MT will be initiated immediately after randomisation, while the PTAS will be performed when patients report relief of alarm symptoms defined as sudden weakness or numbness. All patients will be followed up at 30 days, 3 and 12 months after randomisation. The primary end point will be the incidence of stroke or death at 30 days after randomisation. Secondary outcomes will be the incidence of ischaemic stroke in the territory of stenosis arteries, the incidence of in-stent restenosis, the Chinese version of the modified Rankin Scale and the Chinese version of the Stroke-Specific Quality of Life (CSQoL). ETHICS AND DISSEMINATION: The study protocol is approved by institutional review boards in participating hospitals (reference number FZ20160003, 180PLA20160101 and 476PLA2016007). The results of this study will be disseminated to patients, physicians and policymakers through publication in a peer-reviewed journal or presentations in conferences. It is anticipated that the results of this study will improve the quality of the current PTAS procedure and guide clinical decision-making for patients with ICAS. TRIAL REGISTRATION NUMBER: NCT02689037.


Assuntos
Angioplastia , Arteriosclerose Intracraniana/cirurgia , Stents , Acidente Vascular Cerebral/prevenção & controle , Adulto , Idoso , China , Tomada de Decisão Clínica , Protocolos Clínicos , Constrição Patológica/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida
8.
J Chromatogr Sci ; 53(8): 1265-73, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25657289

RESUMO

A rapid sensitive analytical method was established and validated to investigate levistolide A in rat plasma by liquid chromatography-tandem mass spectrometry operated in the positive ion mode. Levistilide A (LA) and internal standard (IS) andrographolide (AD), mixed with the plasma sample, were separated on a reversed phase Spursil™ C18 5 µm column. The precursor/product transitions (m/z) were 398.5/381.3 for LA and (m/z) 368.0/351.1 for AD. The calibration curve was linear over the range from 5 to 1,250 ng/mL for oral administration and 10-4,000 for intravenous administration with a correlation coefficient (r) ≥0.9993. The lower limit of quantification was 5 ng/mL for LA in plasma. The inter- and intra-day accuracy and precision were less than ±15% of the relative standard deviation. In this study, the developed method is successfully applied to the comparative pharmacokinetic study of LA in rats after oral administration of LA alone, Rhizoma Chuanxiong, and Danggui-Shaoyao-San along with the bioavailability study of LA in rats. Our study shows that low bioavailability (7.5%) is observed after oral administration of LA. Traditional formula compatibility of Danggui-Shaoyao-San could significantly enhance LA bioavailability compared with LA alone and Rhizoma Chuanxiong.


Assuntos
Benzofuranos/sangue , Benzofuranos/farmacocinética , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Benzofuranos/química , Medicamentos de Ervas Chinesas , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Rejuvenation Res ; 18(2): 111-27, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25482164

RESUMO

This study explored the curative effect and underlying mechanisms of a traditional Chinese medicine compound prescription, Bushen-Yizhi formula (BSYZ), in ibotenic acid (IBO)-induced rats. Morris water maze and novel object recognition tests showed that BSYZ significantly improved spatial and object memory. Brain immunohistochemistry staining showed that BSYZ significantly up-regulated expression of choline acetyltransferase (ChAT) and nerve growth factor (NGF) in the hippocampus and cortex. The protein tyrosine kinase high-affinity receptor TrkA was slightly increased in the hippocampus and cortex, and significantly enhanced in the nucleus basalis of Meynert (NBM) after BSYZ intervention. The immunoreactivity of the p75 low-affinity receptor in BSYZ-treated rats was significantly strengthened in the cortex. Similar expression trends of nerve growth factor (NGF), TrkA, and p75 mRNA were observed in the hippocampus and cortex. Additionally, BSYZ reversed IBO-induced disorders of acetylcholine (ACh) levels, ChAT, and cholinesterase (ChE) in the cortex, which was consistent with the changes in mRNA levels of ChAT and acetylcholinesterase (AChE). Expression of ChAT and AChE proteins and mRNA in the hippocampus was up-regulated, whereas the apoptosis-relative protein cleaved caspase-3 was decreased after administration of BSYZ. Moreover, changes in cell death were confirmed by histological morphology. Thus, the results indicated that the BSYZ formula could ameliorate memory impairments in IBO-induced rats, and it exerted its therapeutic action probably by modulating cholinergic pathways, NGF signaling, and anti-apoptosis. Overall, it is suggested that the BSYZ formula might be a potential therapeutic approach for the treatment of Alzheimer's disease (AD) and other cholinergic impairment-related diseases.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Fibras Colinérgicas/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Cognição/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Ácido Ibotênico , Nootrópicos/farmacologia , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Fibras Colinérgicas/metabolismo , Colinesterases/metabolismo , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/psicologia , Modelos Animais de Doenças , Aprendizagem em Labirinto/efeitos dos fármacos , Fator de Crescimento Neural/metabolismo , Proteínas do Tecido Nervoso , Ratos Sprague-Dawley , Receptor trkA/metabolismo , Receptores de Fatores de Crescimento , Receptores de Fator de Crescimento Neural/metabolismo , Reconhecimento Psicológico/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Fatores de Tempo
10.
Int J Mol Med ; 34(2): 429-39, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24919922

RESUMO

Bushen­Yizhi formula (BSYZ), a traditional Chinese medicine formula consisting of six herbs has been reported to possess a neuroprotective effect. The present study aimed to investigate the effects of BSYZ on learning and memory abilities, as well as oxidative stress and neuronal apoptosis in the hippocampus of scopolamine (SCOP)­induced senescence in mice, in order to reveal whether BSYZ is a potential therapeutic agent for Alzheimer's disease (AD). A high­performance liquid chromatography (HPLC) fingerprint was applied to provide a chemical profile of BSYZ. Extracts of BSYZ were orally administered to mice with SCOP­induced memory impairment for two weeks. The learning and memory abilities were determined by the Morris water maze test. The oxidant stress­related indices, such as activity of superoxide dismutase (SOD) and levels of glutathione (GSH) and malondialdehyde (MDA) were examined in hippocampus of SCOP­treated mice. The cell death ratio was assessed by TUNEL staining, while apoptotic­related proteins including Bcl­2 and Bax were determined by immuno-fluorescent staining and western blot analysis. Caspase­3 was determined by western blot analysis. Consequently, a chromatographic condition, which was conducted at 35˚C with a flow rate of 0.8 ml/min on the Gemini C18 column with mobile phase of acetonitrile and water­phosphoric acid (100:0.1, v/v), was established to yield common fingerprint chromatography under 203 nm with a similarity index of 0.986 within 10 batches of BSYZ samples. BSYZ at a dose of 2.92 g/kg significantly improved the cognitive ability, restored the abnormal activity of SOD and increased the levels of MDA and GSH induced by SCOP. Moreover, the neural apoptosis in the hippocampus of SCOP­treated mice was reversed by BSYZ by regulating the expression of Bcl­2, Bax and caspase­3. The results demonstrated that BSYZ had neuroprotective effects in SCOP­induced senescence in mice by ameliorating oxidative stress and neuronal apoptosis in the brain, supporting its potential in AD treatment.


Assuntos
Transtornos Cognitivos/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Envelhecimento/efeitos dos fármacos , Envelhecimento/patologia , Animais , Apoptose/efeitos dos fármacos , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/patologia , Humanos , Camundongos , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Escopolamina/toxicidade
11.
Int J Mol Med ; 33(3): 543-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24378397

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease that is characterized by the accumulation of senile plaque and neurofibrilary tangle formation in the brain, including the cerebral cortex and hippocampus. Nowadays, the first-line treatment for AD is the application of acetylcholinesterase inhibitors. However, acetylcholinesterase inhibitors are basically anti-symptomatic for a limited aspect of AD pathology and are associated with serious side-effects. With the advantage of multiple targets, pathways and systems, Chinese herbal compounds hold promising potential for the development of drugs for the treatment of AD. Over the past few years, with the development of Chinese herbal compounds and in vitro pharmacological studies, cell-based disease models are one of the main methods used to screen Chinese herbal compounds for potential efficacy. Testing the efficacy of possible anti-Alzheimer's disease drugs and the development of new drugs are hindered by the lack of objective high-throughput screening methods. Currently, the assessment of the effects of drugs is usually made by MTT assays, involving laborious, subjective, low-throughput methods. Herein, we suggest a novel application for a real-time cell monitoring device (xCELLigence) that can simply and objectively assess the effective composition of Chinese herbal compounds by assessing amyloid-ß peptide Aß1-42-induced apoptosis in PC12 cells. We detected the proliferation and motility of the cells using a fully automated high-throughput and real-time system. We quantitatively assessed cell motility and determined the real-time IC50 values of various anti-AD drugs that intervene in several developmental stages of Aß1-42-induced apoptosis in PC12 cells, Then, we identified the optimal time phase by curative efficacy. Our data indicate that this technique may aid in the discovery and development of novel anti-Alzheimer's disease drugs. It is possible to utilize a similar technique to measure changes in electrical impedance as cells attach and spread in a culture dish covered with a gold microelectrode array that covers approximately 80% of the area on the bottom of a well. As cells attach and spread on the electrode surface, it leads to an increase in electrical impedance of 9-12. The impedance is displayed as a dimensionless para-meter termed the cell index, which is directly proportional to the total area of tissue culture well that is covered by the cells. Hence, the cell index can be used to monitor cell adhesion, spreading, morphological variation and cell density.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Ensaios de Triagem em Larga Escala , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Avaliação de Medicamentos/métodos , Impedância Elétrica , Células PC12 , Fragmentos de Peptídeos/química , Ratos
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