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1.
Molecules ; 29(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38930823

RESUMO

Propolis is a resinous bee product with a very complex composition, which is dependent upon the plant sources that bees visit. Due to the promising antimicrobial activities of red Brazilian propolis, it is paramount to identify the compounds responsible for it, which, in most of the cases, are not commercially available. The aim of this study was to develop a quick and clean preparative-scale methodology for preparing fractions of red propolis directly from a complex crude ethanol extract by combining the extractive capacity of counter-current chromatography (CCC) with preparative HPLC. The CCC method development included step gradient elution for the removal of waxes (which can bind to and block HPLC columns), sample injection in a single solvent to improve stationary phase stability, and a change in the mobile phase flow pattern, resulting in the loading of 2.5 g of the Brazilian red propolis crude extract on a 912.5 mL Midi CCC column. Three compounds were subsequently isolated from the concentrated fractions by preparative HPLC and identified by NMR and high-resolution MS: red pigment, retusapurpurin A; the isoflavan 3(R)-7-O-methylvestitol; and the prenylated benzophenone isomers xanthochymol/isoxanthochymol. These compounds are markers of red propolis that contribute to its therapeutic properties, and the amount isolated allows for further biological activities testing and for their use as chromatographic standards.


Assuntos
Distribuição Contracorrente , Própole , Própole/química , Distribuição Contracorrente/métodos , Cromatografia Líquida de Alta Pressão , Brasil , Animais , Fracionamento Químico/métodos , Abelhas/química
2.
J Environ Manage ; 328: 116971, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36516708

RESUMO

For the in-situ remediation of the contaminated subsurface environment, the injection of nutrients and microorganisms changes chemical and physical conditions, which control the delivery and immobilization of microorganisms. We investigated the injection strategy for effective bacterial delivery in a bioaugmentation scheme by controlling ionic strength (IS) and pore-water velocity (v). A set of bacterial transport tests was conducted using the saturated sand column to mimic the saturated subsurface environment. The effectiveness of the injection strategies was evaluated by applying solutions with different ionic strengths into the sand column with different pore-water velocities. The deposition and delivery of bacteria through the sand column were analyzed using the first-order deposition model. The deposition and delivery of bacteria injected by various strategies were numerically simulated considering the variable deposition rate. The breakthrough curves from column experiments revealed that the bacterial deposition on the sand surface was increased by an increase in the ionic strength and by a decrease in the pore-water velocities. The rates of bacterial deposition (k1) on sand could be determined as a function of ionic strength and pore-water velocity, and it was applicable to simulate the delivery of bacteria under dynamic groundwater conditions. The numerical case study considering various injection strategies showed that the nutrient concentration controlled the bacterial delivery to the target area more significantly than the injection flow rate. Injection of bacterial solution with lower nutrient concentration could be increased the deposited bacterial concentration at the target point (Stp) by 6.2-7.1 times higher. Short pulse injection with a high injection rate decreased Stp by 67-78%. The efficiency of bacterial delivery (Ed) could be increased three times higher by lowering nutrient concentration in the injection solution. The process of evaluating the efficiency of bacterial delivery could be a prominent approach to determining the injection strategy for in-situ remediation considering variable conditions of a contaminated site.


Assuntos
Areia , Água , Água/química , Concentração Osmolar , Porosidade , Dióxido de Silício
3.
Int J Hyperthermia ; 32(2): 132-43, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26758242

RESUMO

OBJECTIVES: The objective of this study was to identify an injection strategy leading to repeatable nanoparticle deposition patterns in tumours and to quantify volumetric heat generation rate distribution based on micro-CT Hounsfield unit (HU) in magnetic nanoparticle hyperthermia. METHODS: In vivo animal experiments were performed on graft prostatic cancer (PC3) tumours in immunodeficient mice to investigate whether lowering ferrofluid infusion rate improves control of the distribution of magnetic nanoparticles in tumour tissue. Nanoparticle distribution volume obtained from micro-CT scan was used to evaluate spreading of the nanoparticles from the injection site in tumours. Heating experiments were performed to quantify relationships among micro-CT HU values, local nanoparticle concentrations in the tumours, and the ferrofluid-induced volumetric heat generation rate (q(MNH)) when nanoparticles were subject to an alternating magnetic field. RESULTS: An infusion rate of 3 µL/min was identified to result in the most repeatable nanoparticle distribution in PC3 tumours. Linear relationships have been obtained to first convert micro-CT greyscale values to HU values, then to local nanoparticle concentrations, and finally to nanoparticle-induced q(MNH) values. The total energy deposition rate in tumours was calculated and the observed similarity in total energy deposition rates in all three infusion rate groups suggests improvement in minimising nanoparticle leakage from the tumours. The results of this study demonstrate that micro-CT generated q(MNH) distribution and tumour physical models improve predicting capability of heat transfer simulation for designing reliable treatment protocols using magnetic nanoparticle hyperthermia.


Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita/administração & dosagem , Neoplasias/metabolismo , Neoplasias/terapia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Injeções , Nanopartículas de Magnetita/uso terapêutico , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/diagnóstico por imagem , Microtomografia por Raio-X
4.
J Therm Biol ; 62(Pt B): 129-137, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27888926

RESUMO

OBJECTIVES: The objective is to design heating protocols to completely damage PC3 tumors after a single magnetic nanoparticle hyperthermia session with minimal collateral thermal damage, based on microCT image generated tumor and mouse models. METHODS: Tumor geometries and volumetric heat generation rate distributions that are generated from microCT scans in our previous study are imported into COMSOL 4.3® multiphysics for heat transfer simulations and heating protocol design using the Arrhenius damage model. Then, parametric studies are performed to evaluate how significantly the infusion rate affects the protocol design and its resulted collateral thermal damage. RESULTS: The simulated temperature field in the generated tumor geometry and volumetric heat generation rate distribution are reasonable and correlates well with the amount of the total thermal energy deposited into the tumors. The time needed for complete thermal damage is determined to be approximately 12min or 25min if one uses the Arrhenius integral Ω equal to 1 or 4 as the damage threshold, when the infusion rate is 3µL/min. The heating time increases 26% or 91% in the higher infusion rate groups of 4 or 5µL/min, respectively. Collateral thermal damage to the surrounding tissue is also assessed. Although the two larger infusion rate groups can still cause thermal damage to the entire tumor, the collateral thermal damage would have exceeded the design criterion of 5%, while the assessment criterion is acceptable only in the infusion rate group of 3µL/min. Based on the results of this study, we identify an injection strategy and heating protocols to be implemented in future animal experiments to evaluate treatment efficacy for model validation.


Assuntos
Hipertermia Induzida/métodos , Nanopartículas de Magnetita/uso terapêutico , Modelos Biológicos , Neoplasias/terapia , Temperatura , Microtomografia por Raio-X/métodos , Animais , Linhagem Celular Tumoral , Simulação por Computador , Modelos Animais de Doenças , Calefação/métodos , Temperatura Alta , Humanos , Hipertermia Induzida/instrumentação , Camundongos
5.
Dermatol Ther (Heidelb) ; 14(6): 1671-1682, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38824483

RESUMO

INTRODUCTION: Recent advancements in androgenetic alopecia (AGA) treatment have highlighted the efficacy of botulinum toxin (BoNT). However, inconsistencies in injection sites and depths warrant attention. It remains unclear which injection strategy is most beneficial for patients. METHODS: This split-scalp randomized controlled trial divided each enrolled participant's scalp along the midline: one side was randomized to receive intramuscular BoNT injections in the surrounding muscles, while the other side received intradermal BoNT injections directly into the balding areas. This study evaluated the impact of treatment on hair density and diameter through trichoscopic examinations conducted at baseline and 12 weeks post treatment. Additionally, assessments of pain and overall safety were integrated into the study protocol. RESULTS: Twenty-nine patients completed the study, with significant improvements in hair density observed in the intramuscular injection group compared to the intradermal group (p < 0.001). Both groups exhibited increases in hair diameter, but no significant difference was found between the two methods (p = 0.433). Pain evaluation revealed that intradermal injections in balding areas were more painful than intramuscular injections (p = 0.036), with no severe adverse reactions reported except for a single case of alopecia areata following injection. CONCLUSION: Our research revealed that both BoNT injection strategies enhanced hair diameter 12 weeks post-treatment, with intramuscular injections significantly improving hair density more effectively. Despite the promising outcomes, the variability in patient responses underscores the necessity for personalized approaches and further research to refine injection protocols for optimized efficacy and safety. TRIAL REGISTRATION NUMBER: ChiCTR2400080190.

6.
Natl Sci Rev ; 11(8): nwae238, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39131923

RESUMO

Rechargeable magnesium batteries (RMBs) have received increased attention due to their high volumetric capacity and safety. Nevertheless, the sluggish diffusion kinetics of highly polarized Mg2+ in host lattices severely hinders the development of RMBs. Herein, we report an electron injection strategy for modulating the Mo 4d-orbital splitting manner and first fabricate a dual-phase MoO2.8F0.2/MoO2.4F0.6 heterostructure to accelerate Mg2+ diffusion. The electron injection strategy triggers weak Jahn-Teller distortion in MoO6 octahedra and reorganization of the Mo 4d-orbital, leading to a partial phase transition from orthorhombic phase MoO2.8F0.2 to cubic phase MoO2.4F0.6. As a result, the designed heterostructure generates a built-in electric field, simultaneously improving its electronic conductivity and ionic diffusivity by at least one order of magnitude compared to MoO2.8F0.2 and MoO2.4F0.6. Importantly, the assembled MoO2.8F0.2/MoO2.4F0.6//Mg full cell exhibits a remarkable reversible capacity of 172.5 mAh g-1 at 0.1 A g-1, pushing forward the orbital-scale manipulation for high-performance RMBs.

7.
Med Eng Phys ; 113: 103965, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36966004

RESUMO

Effects of injection rate and tumor physiology on the diffusion of magnetic nano-particles (MNPs) and temperature profile during magnetic hyperthermia are investigated in this work. The study considers three injection rates (2.5 µL/min, 10 µL/min, and 40 µL/min), and two MNP diffusion coefficients (10-9 m2/s and 10-11 m2/s). The simulation of this physics has been done on 3D tumor surrounded by healthy tissue. Transient MNP distribution in tissue is evaluated using Darcy's flow model and the MNP transport (convection-diffusion) equation. The temperature profile in the tumor model is computed by solving Penne's bioheat transfer equation (PBHTE). Results show tumors with high collagen content (with low MNP diffusivity) are more restrictive towards MNP transport than tumors having low collagen content. Thus, tumors with low MNP diffusivity need a higher injection rate to increase the homogeneity of MNP concentration as well as temperature profile during thermo-therapy. Results also show that, MNP fluid injected with a higher injection rate produces a more uniform MNP concentration up to greater depth than the lower injection rate.


Assuntos
Hipertermia Induzida , Neoplasias , Nanopartículas , Humanos , Difusão , Fenômenos Magnéticos
8.
Front Chem ; 10: 1020484, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277337

RESUMO

Inorganic perovskites have been recognized as highly potent materials for the display and medical industries due to their outstanding features. However, there haven't been many reports on their implications as a photocatalyst for the removal of heavy metals. Photocatalysis has been regarded as a significant approach for the removal of pollutants because of its great sustainability, improved efficiency, and reduced energy consumption. Here, we applied inorganic cesium lead halides (Br and I) with zinc oxide heterostructure as a photocatalyst for the first time. The heterostructure has been synthesized by the traditional hot injection strategy and its photocatalytic activity was systematically investigated. Interestingly, the CsPbX3/ZnO heterostructure as a photocatalyst has a homogeneous geometry and possesses an excellent degradation efficiency of over 50% under xenon UV-Visible light. The CsPbX3/ZnO catalyst carries superior oxidation/reduction properties and ionic conductivity due to the synergistic photogenerated charge carrier and interaction between CsPbX3 and ZnO. The recycling experiment showed the good stability of the catalysts. These findings suggest that inorganic lead halide heterostructure has the potential to be used for heavy metal degradation and water pollution removal catalysts.

9.
Environ Pollut ; 255(Pt 2): 113260, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31622808

RESUMO

Emissions from ships at berth are small compared to the total ship emissions; however, they are one of the main contributors to pollutants in the air of densely-populated areas, consequently heavily affecting public health. This is due to auxiliary marine engines being used to generate electric power and steam for heating and providing services. The present study has been conducted on an engine representative of a marine auxiliary, which was a heavy duty, six-cylinder, turbocharged and after-cooled engine with a high pressure common rail injection system. Engine performance and emission characterisations during cold start are the focus of this paper, since cold start is significantly influential. Three tested fuels were used, including the reference diesel and two IMO (International Maritime Organization) compliant spiked fuels. The research engine was operated at a constant speed and 25% load condition after 12 h cooled soak. Results show that during cold start, significant heat generated from combustion is used to heat the engine block, coolant and lubricant. During the first minute, compared to the second minute, emissions of particle number (PN), carbon monoxide (CO), particulate matter (PM), and nitrogen oxides (NOx) were approximately 10, 4, 2 and 1.5 times higher, respectively. The engine control unit (ECU) plays a vital role in reducing engine emissions by changing the engine injection strategy based on the engine coolant temperature. IMO-compliant fuels, which were higher viscosity fuels associated with high sulphur content, resulted in an engine emission increase during cold start. It should be taken into account that auxiliary marine diesel engines, working at partial load conditions during cold start, contribute considerably to emissions in coastal areas. It demonstrates a need to implement practical measures, such as engine pre-heating, to obtain both environmental and public health advantages in coastal areas.


Assuntos
Automóveis , Temperatura Baixa , Gasolina/análise , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , Óxidos de Nitrogênio/análise , Material Particulado/análise , Navios , Enxofre/análise , Temperatura
10.
Anal Chim Acta ; 1063: 99-109, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30967192

RESUMO

The ability of LC-MS/MS for high coverage metabolite analysis lags behind the requirements of global metabolomics. The introduction of chemical derivatizations could significantly extend the ability of LC-MS/MS with enhanced MS response and improved LC separation, which has been serving as a promising quantitative tool for metabolomic analysis. However, as one specific derivatization reagent usually targets to a certain moiety, only a single chemical-group-based submetabolome could be analyzed in one injection. Therefore, the coverage of detected metabolites by derivatization-based LC-MS/MS is largely limited. To overcome this technical obstacle of derivatization-based LC-MS and increase submetabolome coverage, we proposed an extendable all-in-one injection LC-MS/MS strategy. 5-dimethylamino-naphthalene-1-sulfonyl chloride (Dns-Cl)/5-diethylamino-naphthalene-1-sulfonyl chloride (Dens-Cl) and 5-dimethylamino-naphthalene-1-sulfonyl piperazine (Dns-PP)/5-diethylamino-naphthalene-1-sulfonyl piperazine (Dens-PP) were used as twins labeling reagents for amino/phenol and carboxyl submetabolomes, respectively. "Series Mode" and "Parallel Mode" were proposed and investigated using eight representative standards with the consideration of interaction between different derivatization systems, time-consumption, and extendability. As a result, we found that "Series Mode" led to yield reduction, while "Parallel Mode" gave identical results with those of individual derivatization. Finally, a "Parallel Mode" was chosen to develop an extendable all-in-one injection twin derivatization LC-MS/MS strategy to quantify eighty metabolites assigned to five classes of microbial metabolites, including polyamines, amino acids, indole derivatives, bile acids, and free fatty acids. This well-validated method quantified 67 metabolites absolutely and discovered additional 40 differential metabolites compared with the untargeted method in rat serum from irinotecan (CPT-11)-induced gastrointestinal toxicity model.


Assuntos
Metabolômica/instrumentação , Metabolômica/métodos , Aminoácidos/sangue , Aminoácidos/metabolismo , Animais , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/metabolismo , Cromatografia Líquida , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos não Esterificados/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Indóis/sangue , Indóis/metabolismo , Irinotecano/toxicidade , Poliaminas/sangue , Poliaminas/metabolismo , Ratos , Espectrometria de Massas em Tandem
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