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1.
BMC Infect Dis ; 24(1): 980, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285332

RESUMO

BACKGROUND: Cystic echinococcosis (CE) is prevalent in livestock farming regions around the world. However, it remains relatively rare compared to other infectious diseases. CE typically affects the liver, lungs, brain, and kidneys. Spinal and pleural wall involvement is exceedingly rare. We report a unique case of intradural and pleural wall CE in a young male, successfully treated with surgery and postoperative medication. CASE PRESENTATION: A 19-year-old Tibetan male from the Qinghai-Tibet Plateau was diagnosed with intradural and pleural wall CE through imaging, serology, and surgical pathology. According to the Dew/Braithwaite & Lees (BL) classification, his condition was an exceptionally rare form of spinal echinococcosis, compounded by an even rarer pleural wall involvement. Prompt surgical intervention and postoperative medication resulted in significant improvement in spinal cord compression symptoms. CONCLUSIONS: This case highlights the diagnostic and therapeutic challenges of rare CE locations. MRI proved superior to CT in diagnosing bony cystic echinococcosis. Early surgical intervention combined with medication facilitates spinal cord function recovery, providing valuable insights for managing similar cases.


Assuntos
Equinococose , Humanos , Masculino , Equinococose/cirurgia , Equinococose/diagnóstico por imagem , Equinococose/diagnóstico , Equinococose/tratamento farmacológico , Adulto Jovem , Imageamento por Ressonância Magnética , Pleura/patologia , Pleura/diagnóstico por imagem , Pleura/cirurgia , Tomografia Computadorizada por Raios X , Tibet , Compressão da Medula Espinal/cirurgia , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/parasitologia
2.
Foods ; 13(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38890947

RESUMO

This study aimed to investigate the efficacy of supercritical CO2 (SC-CO2) extraction in enhancing the extraction rate, purity, and antioxidant activity of Indocalamus latifolius (Keng) McClure (Poaceae) leaf terpenoids (ILLTs). Crude extracts obtained from leaves were subjected to qualitative and quantitative analyses, revealing neophytadiene, phytol, ß-sitosterol, ß-amyrone, squalene, and friedelin as the primary terpenoid constituents, identified through gas chromatography-mass spectrometry (GC-MS). Compared with steam distillation extraction (SD), simultaneous distillation extraction (SDE), ultra-high pressure-assisted n-hexane extraction (UHPE-Hex), ultra-high pressure-assisted ethanol extraction (UHPE-EtOH), ultrasound-assisted n-hexane extraction (UE-Hex), and ultrasound-assisted ethanol extraction (UE-EtOH), SC-CO2 exhibited a superior ILLT extraction rate, purity, and antioxidant activity. Scanning electron microscopy (SEM) observations of the residues further revealed more severe damage to both the residues and their cell walls after SC-CO2 extraction. Under optimal parameters (4.5 h, 26 MPa, 39 °C, and 20% ethyl alcohol), the ILLT extraction rate with SC-CO2 reached 1.44 ± 0.12 mg/g, which was significantly higher than the rates obtained by the other six methods. The subsequent separation and purification using WelFlash C18-l, BUCHI-C18, and Sephadex LH-20 led to an increase in the purity of the six terpenoid components from 12.91% to 93.34%. Furthermore, the ILLTs demonstrated cytotoxicity against HepG2 cells with an IC50 value of 148.93 ± 9.93 µg/mL. Additionally, with increasing concentrations, the ILLTs exhibited an enhanced cellular antioxidant status, as evidenced by reductions in both reactive oxygen species (ROS) and malondialdehyde (MDA) levels.

3.
J Sci Food Agric ; 104(12): 7536-7549, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38747177

RESUMO

BACKGROUND: To improve phytol bioavailability, a novel method of magnetic stirring and high-pressure homogenization (HPH) combination was used to prepare zein/fucoidan-coated phytol nanoliposomes (P-NL-ZF). The characterization, the simulated in vitro digestion, and the antioxidant activity of these phytol nanoliposomes from the different processes have been studied. RESULTS: Based on the results of dynamic light scattering (DLS) and gas chromatography-mass spectrometer (GC-MS) analysis, P-NL-ZF prepared through the combination of magnetic stirring and HPH exhibited superior encapsulation efficiency at 76.19% and demonstrated exceptional physicochemical stability under a series of conditions, including storage, pH, and ionic in comparison to single method. It was further confirmed that P-NL-ZF by magnetic stirring and HPH displayed a uniform distribution and regular shape through transmission electron microscopy (TEM). Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) analysis showed that electrostatic interactions and hydrogen bonding were the primary driving forces for the formation of composite nanoliposomes. Additionally, an in vitro digestion study revealed that multilayer composite nanoliposomes displayed significant and favorable slow-release properties (58.21%) under gastrointestinal conditions compared with traditional nanoliposomes (82.36%) and free phytol (89.73%). The assessments of chemical and cell-based antioxidant activities demonstrated that the coating of zein/fucoidan on phytol nanoliposomes resulted in enhanced effectiveness in scavenging activity of ABTS free radical and hydroxyl radical and mitigating oxidative damage to HepG2 cells. CONCLUSION: Based on our studies, the promising delivery carrier of zein/fucoidan-coated nanoliposomes is contributed to the encapsulation of hydrophobic natural products and enhancement of their biological activity. © 2024 Society of Chemical Industry.


Assuntos
Antioxidantes , Lipossomos , Nanopartículas , Fitol , Zeína , Antioxidantes/química , Antioxidantes/farmacologia , Lipossomos/química , Zeína/química , Fitol/química , Nanopartículas/química , Humanos , Tamanho da Partícula , Estabilidade de Medicamentos , Composição de Medicamentos/métodos , Polissacarídeos/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos
4.
Environ Sci Process Impacts ; 25(1): 66-74, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36504232

RESUMO

Organic compounds are capable of generating hydroxyl radicals (˙OH) through their excited triplet states in natural water. It is of significance to reveal the underlying mechanism of the generation and obtain the generation quantum yield of ˙OH from organic compounds for better understanding of its involvement in indirect photochemical processes in the environment. In this study, the ˙OH quantum yields (Φ˙OH) of 20 organic compounds were determined by photochemical experiments. The calculated Φ˙OH values for the selected organic compounds vary from (1.2 ± 0.39) × 10-5 to (7.2 ± 0.16) × 10-4. A quantitative structure-activity relationship (QSAR) model for log Φ˙OH was developed and the established model was proven to have a proper goodness of fit, robustness, and predictive ability. The QSAR model was successfully used to predict the Φ˙OH value of organic pollutants. Mechanistic interpretation showed that the electron distribution and the electronegativity of organic compounds are the most important factors that determine the generation of ˙OH. The results are helpful for understanding the generation mechanism of ˙OH from organic compounds and also provide insights into the generation of ˙OH from dissolved organic matter in natural water.


Assuntos
Radical Hidroxila , Poluentes Químicos da Água , Radical Hidroxila/química , Relação Quantitativa Estrutura-Atividade , Compostos Orgânicos , Água/química , Processos Fotoquímicos , Poluentes Químicos da Água/análise
5.
Environ Pollut ; 260: 114101, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32084701

RESUMO

The conductive polyurethane/polypyrrole/graphene (CPU/PPy/Gr) particle electrode was prepared by an in-situ oxidative polymerization method and used as particle electrodes to degrade levofloxacin (LEV) in a three-dimensional electrode reactor. The prepared CPU/PPy/Gr electrode was characterized systematically and the effects of initial pH, initial LEV concentration, aeration volume, voltage, and electrolyte concentration on the degradation efficiency were investigated. Results showed that more than 90% LEV was degraded and the energy consumption was 20.12 kWh/g LEV under conditions of pH 7, 6 V voltage, 2.0 L/min aeration volume, 20 mg/L initial LEV concentration, and 7 mM concentration of electrolyte (Na2SO4). A possible electrochemical oxidation pathway of LEV by the CPU/PPy/Gr electrode was proposed. In addition, the biotoxicity of LEV and its oxidation products was calculated using ECOSAR (Ecological Structure Activity Relationships) program in EPISuite. Toxicity evaluation using luminescent bacteria showed that the toxicities of some intermediates were higher than the parent compound. But the toxicity of degradation processes for LEV was effective decreasing. A possible reactive mechanism in the three-dimensional reactor was also recommended. In brief, the prepared CPU/PPy/Gr particle electrode constitutes an insight into the promising practical application in the wastewater treatment.


Assuntos
Grafite , Levofloxacino/química , Poliuretanos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Eletrodos , Polímeros , Pirróis
6.
Sci Total Environ ; 712: 136450, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31931195

RESUMO

Singlet oxygen (1O2) is capable of degrading organic contaminants and inducing cell damage and inactivation of viruses. It is mainly generated through the interaction of dissolved oxygen with excited triplet states of dissolved organic matter (DOM) in natural waters. The present study aims at revealing the underlying mechanism of 1O2 generation and providing a potential tool for predicting the quantum yield of 1O2 (Φ1O2) generation from DOM by constructing a quantitative structure-activity relationship (QSAR) model. The determined Φ1O2 values for the selected DOM-analogs range from (0.54 ± 0.23) × 10-2 to (62.03 ± 2.97) × 10-2. A QSAR model was constructed and was proved to have satisfactory goodness-of-fit and robustness. The QSAR model was successfully used to predict the Φ1O2 of Suwannee River fulvic acid. Mechanistic interpretation of the descriptors in the model showed that hydrophobicity, molecular complexity and the presence of carbonyl groups in DOM play crucial roles in the generation of 1O2 from DOM. The presence of other heteroatoms besides O, such as N and S, also affects the generation of 1O2. The results of this study provide valuable insights into the generation of 1O2 from DOM in sunlit natural waters.

7.
Chemosphere ; 235: 900-907, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31299703

RESUMO

Effluent organic matter (EfOM), which is composed of background natural organic matter (NOM), soluble microbial degradation products, and trace amounts of organic pollutants, can play an important role in the photodegradation of emerging pollutants in the effluent. In this study, the impact of organic pollutants, using fenofibrate acid (FNFA) as a representative, on the photodegradation of emerging contaminants, using bezafibrate (BZF) as a representative, in effluents was investigated. It is found that BZF undergo fast degradation in the presence of FNFA although BZF is recalcitrant to degradation under simulated sunlight irradiation. The promotional effect of FNFA is due to the generation of singlet oxygen (1O2) and hydrated electrons (e-aq). Based on the structures of the identified intermediates, 1O2 initiated oxidation and e-aq initiated reduction reactions were the main photodegradation pathways of BZF in the effluents. The toxicity of the main photodegradation intermediates for BZF and FNFA was higher than that of the parent compounds, and the acute toxicity increased during simulated sunlight irradiation. The results demonstrated that trace amounts of organic compounds in EfOM can play an important role in sensitizing the photodegradation of some emerging pollutants in the effluent.


Assuntos
Bezafibrato/química , Fenofibrato/química , Fotólise , Poluentes Químicos da Água/análise , Oxirredução , Oxigênio Singlete/química , Luz Solar
8.
Bioresour Technol ; 290: 121751, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31301571

RESUMO

The removal of antibiotics from wastewater has attracted much attention. In this research, an intimately coupled autarkical electrosorption (ES)-microbial fuel cell (MFC) system was developed for real-time removal of the antibiotic oxytetracycline (OTC) from wastewater. The removal efficiency was founded to be up to 98.8% at an OTC concentration of 2 mg/L with 3 g/L sodium acetate (NaAC) as co-substrate and 3 MFCs as power supply. The removal efficiencies increased in the ES unit and decreased in the MFC unit with increasing treating time. The adsorption of OTC on activated carbon fibers (ACFs) in the ES unit proceeds via chemical adsorption resulting from electrostatic attraction and cation exchange. The OTC degradation pathways in the MFC unit were proposed by identifying the intermediates with HPLC-MS/MS. The ACFs in the ES unit were proven to be recyclable and the coupled ES-MFC system is applicable for the removal of antibiotics from wastewater.


Assuntos
Fontes de Energia Bioelétrica , Oxitetraciclina , Eletricidade , Espectrometria de Massas em Tandem , Águas Residuárias
9.
Environ Sci Process Impacts ; 21(1): 155-162, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30620012

RESUMO

Estuarine waters of variable compositions are sinks for many micropollutants. The varying water properties can impact the photodegradation of organic pollutants. In this study, the combined effects of dissolved organic matter (DOM), pH, ionic strength, and halides on the photodegradation of the model organic pollutant oxytetracycline (OTC) were investigated. Suwannee River natural organic matter (SRNOM) was used as a representative DOM. The results showed that the observed photolysis rate constant (kobs) of OTC increased rapidly upon increase of pH. SRNOM induced a 11.0-17.9% decrease of the kobs for OTC. In the presence of SRNOM, the ionic strength and specific halide effects promote OTC photodegradation with a 39.2-84.2% and 7.1-28.8% increase of the kobs, respectively. The effects of SRNOM, ionic strength and halides on OTC photodegradation are pH-dependent. Direct photolysis half-lives (t1/2) of OTC were estimated in view of the more important role of direct photolysis compared to indirect photolysis. The estimated t1/2 values decreased from 187.4-206.6 d to 34.4-36.6 d as the pH increases in the Yellow River estuarine region. The results of this research demonstrate that the photodegradation rate of OTC increases rapidly in the gradient from river water to marine water in estuarine regions.


Assuntos
Oxitetraciclina/química , Poluentes Químicos da Água/química , Estuários , Concentração de Íons de Hidrogênio , Concentração Osmolar , Oxitetraciclina/análise , Oxitetraciclina/efeitos da radiação , Fotólise , Rios/química , Raios Ultravioleta , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/efeitos da radiação
10.
J Hazard Mater ; 358: 216-221, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29990809

RESUMO

Pharmaceuticals are a group of ubiquitous emerging pollutants, many of which have been shown to undergo efficient photolysis in the environment. Photochemically produced reactive intermediates (PPRIs) sensitized by the pharmaceuticals in sunlit natural waters may induce photodegradation of coexisting compounds. In this study, the roles of coexisting contaminants on the phototransformation of pharmaceuticals were unveiled with the fibrate drugs gemfibrozil (GMF), fenofibrate (FNF), and fenofibric acid (FNFA) as model compounds. GMF undergoes initial concentration dependent photodegradation due to the involvement of singlet oxygen (1O2) initiated self-sensitized photolysis, and undergoes pH dependent photodegradation due to dissociation and hydroxyl radical (OH) generation. The decarboxylated intermediates of GMF and coexisting FNFA significantly accelerated the photodegradation of GMF. The promotional effects of the decarboxylated intermediates are attributed to generation of PPRIs, e.g. 1O2, superoxide (O2-), that subsequently react with GMF. Besides, FNFA can also promote the photodegradation of GMF through the electron transfer reaction from ground state GMF to excited state FNFA, leading to the formation of decarboxylated intermediates. The formed intermediates can subsequently also facilitate GMF photodegradation. The results presented here provided valuable novel insights into the effects of coexisting contaminants on the photodegradation of pharmaceuticals in polluted waters.


Assuntos
Fenofibrato/análogos & derivados , Genfibrozila/análise , Luz , Preparações Farmacêuticas/análise , Fotólise , Poluentes Químicos da Água/análise , China , Fenofibrato/análise , Fenofibrato/efeitos da radiação , Genfibrozila/efeitos da radiação , Concentração de Íons de Hidrogênio , Modelos Teóricos , Estrutura Molecular , Preparações Farmacêuticas/efeitos da radiação , Rios/química , Poluentes Químicos da Água/efeitos da radiação
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