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1.
Int J Mol Sci ; 22(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34502323

RESUMO

The aim of the study was the multi-elemental analysis of aqueous humor (AH) collected from patients undergoing cataract surgery. The study included: 16 patients with age-related macular degeneration AMD (99 controls), 10 patients with retinopathy (105 controls), 61 patients with hypertension (54 controls), and 33 patients with coexisting diabetes (82 controls). The control groups were recruited from patients with a lack of co-existing disease characterizing the specified studied group. The measurements were performed by the use of inductively coupled plasma optical emission spectrometry (ICP-OES). The statistical analysis was carried out using non-parametric testing (Mann-Whitney U). The level of significance was set at p = 0.05. The data obtained revealed substantial variations in elemental composition between the test groups in comparison to the controls. However, the significant variations concerned only a few elements. The phosphorous (P) level and the ratio of P/Ca were significant in retinopathy and diabetes, whereas cobalt (0.091 ± 0.107 mg/L vs. 0.031 ± 0.075 mg/L; p = 0.004) was significant in AMD. In co-existing hypertension, the levels of tin (0.293 ± 0.409 mg/L vs. 0.152 ± 0.3 mg/L; p = 0.031), titanium (0.096 ± 0.059 mg/L vs. 0.152 ± 0.192 mg/L; p = 0.045), and ruthenium (0.035 ± 0.109 mg/L vs. 0.002 ± 0.007 mg/L; p = 0.006) varied in comparison to the controls. The study revealed inter-elemental interactions. The correlation matrices demonstrated the domination of the positive correlations, whereas negative correlations mainly concerned sodium.


Assuntos
Humor Aquoso/metabolismo , Catarata/metabolismo , Diabetes Mellitus/fisiopatologia , Retinopatia Diabética/fisiopatologia , Elementos Químicos , Hipertensão/fisiopatologia , Degeneração Macular/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Catarata/epidemiologia , Catarata/patologia , Catarata/terapia , Extração de Catarata , Feminino , Seguimentos , Humanos , Cristalino/cirurgia , Masculino , Pessoa de Meia-Idade , Polônia/epidemiologia , Prognóstico
2.
Materials (Basel) ; 13(11)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32532041

RESUMO

The cell membrane is a complex system that consists of lipids, proteins, polysaccharides, and amphiphilic phospholipids. It plays an important role in ADME processes that are responsible for the final pharmaceutical effects of xenobiotics (bioavailability, activity). To study drug-membrane interaction at the molecular level, several high-performance liquid chromatography (HPLC) membrane model systems have been proposed which are mimicking mainly its lipid character. The aim of this work was to study interactions of new synthesized antiepileptic compounds of 4-alkyl-5-(3-chlorophenyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione derivatives with Chirobiotic column containing glycoprotein ligand attached to the silica matrix. The affinity of the analytes to immobilized glycoprotein ligand was examined chromatographically in reversed-phase mode. The thermodynamics of interactions between bioactive compounds and teicoplanin was studied in terms of the van't Hoff linear relationship ln k vs. 1/T in the range of 5-45 °C. Change in enthalpy (ΔH°), change in entropy (ΔS°) and change in Gibbs free energy (ΔG°) were estimated utilizing graphical extrapolation and interpolation methods. The density functional theory (DFT) approach and docking simulations were used to get the molecular interpretation and prove the obtained experimental results. Cross-correlations of chromatographic and thermodynamic parameters with non-empirical topological and quantum chemical indices suggest that the polarizability of analytes appears to be responsible for the interactions of the tested molecules with teicoplanin and, ultimately, their retention on the column. Experimental and theoretical parameters were subjected to statistical analysis using regression models. Partial least squares (PLS) regression model showed the usefulness of the experimentally measured parameter φ0 (MeOH) to discriminate between anticonvulsant active and inactive 1,2,4-triazole-3-thione derivatives. Obtained results point out the usefulness of interaction of potential anticonvulsants with glycoprotein class of compounds to anticipate their activity.

3.
Sensors (Basel) ; 20(7)2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32235669

RESUMO

The paper presented the methodology for the construction of a soft sensor used for activated sludge bulking identification. Devising such solutions fits within the current trends and development of a smart system and infrastructure within smart cities. In order to optimize the selection of the data-mining method depending on the data collected within a wastewater treatment plant (WWTP), a number of methods were considered, including: artificial neural networks, support vector machines, random forests, boosted trees, and logistic regression. The analysis conducted sought the combinations of independent variables for which the devised soft sensor is characterized with high accuracy and at a relatively low cost of determination. With the measurement results pertaining to the quantity and quality of wastewater as well as the temperature in the activated sludge chambers, a good fit can be achieved with the boosted trees method. In order to simplify the selection of an optimal method for the identification of activated sludge bulking depending on the model requirements and the data collected within the WWTP, an original system of weight estimation was proposed, enabling a reduction in the number of independent variables in a model-quantity and quality of wastewater, operational parameters, and the cost of conducting measurements.

4.
Molecules ; 25(2)2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952277

RESUMO

Trace element distribution varies in different locations of the human brain. Several elements were found to cause various negative effects, such as neurodegeneration. In this paper, we analyzed the interactions between seven trace elements: zinc (Zn), selenium (Se), manganese (Mg), iron (Fe), copper (Cu), chromium (Cr) and cobalt (Co) in individuals with alcohol use disorder (AUD) and individuals without (control group). Brain tissue samples from 31 individuals with AUD and 31 control subjects were harvested. Inductively coupled plasma optical emission spectrometry was used for trace element determination. In the control group, there were several positive correlations between Cr, Cu, Fe and Mn. In the AUD group, positive correlations between Co and Cr, Cu, Fe, Mn, Zn were found. The majority of correlations between Zn and other elements are positive. In the studied group, Mn had strong positive correlations with Co, Cr, Cu and Fe. The strongest positive correlation found between average element concentration was between Cu and Cr. The knowledge of kinetics and metabolism of trace elements as well as the impact of alcohol on these processes is essential for understanding the pathological processes and functioning of human brain tissue.


Assuntos
Alcoolismo/patologia , Encéfalo/metabolismo , Oligoelementos/análise , Oligoelementos/metabolismo , Alcoolismo/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
5.
Molecules ; 24(22)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31739645

RESUMO

Trace elements play an important role in the pathogenesis of several serious ophthalmological disorders, such as glaucoma, age-related macular degeneration (AMD), diabetic retinopathy, cataract, etc. This study aimed to measure alterations of chemical elements' (67) levels in the aqueous humor of patients undergoing cataract surgery. The pilot study included 115 patients, (age 74 ± 7.27, female 64.35%, male 35.65%). The aqueous levels of elements were measured by the use of the inductively coupled plasma optical emission spectrometry (ICP-OES), quality controlled with certified standards. The classification of elements based on their concentration was achieved by hierarchical cluster analysis. This is the first screening study that quantifies over 60 elements which are present in the fluid from the anterior chamber of the eye of cataract patients. The obtained results can be suitable for understanding and identifying the causes that may play a role in the initiation and progression of lens opacity.


Assuntos
Humor Aquoso/química , Catarata/metabolismo , Oligoelementos/análise , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Projetos Piloto
6.
Materials (Basel) ; 12(15)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357519

RESUMO

This article analyses the connection of the two types of floors on the ground (floors on joists and self-supporting floors), with the external wall made of a hemp-lime composite for the occurrence of thermal bridges. Several factors that may affect the heat transfer in the junction were taken into account: the level of the floor on the ground, the wall thickness, the thermal conductivity of the composite, and the location of the timber frame construction. The technology of using hemp and lime is relatively new, and there is a lack of such analyses in the literature. The two-dimensional (2D) heat-transfer in the described construction joints was analyzed based on the finite-element method with the use of the THERM 7.4 software. The results were presented as averaged and linear thermal transmittance coefficients dependent on the above mentioned factors. The possibility of surface condensation was also checked. The differences in the values of the thermal transmittance of the junction between the two variants of ground floors reached around 0.13%-1.67% and the values of linear thermal transmittance factor reached approximately 2.43%-10.13%. The junctions with the highest floor level showed a decrease in the thermal transmittance value by about 3.00%-5.77% and in the linear thermal transmittance, by about 21.98%-53.83%, compared to the junctions with the lowest floor level. Calculations showed that almost all analyzed junctions are free from surface condensation causing mould growth, because the minimum temperature factors f0.25 were higher than 0.78 (except for junctions with the lowered floor levels). The junction with a floor on the timber joists showed better thermal parameters than the junction with a self-supporting floor in each of the analyzed variants. By increasing the level of floor insulation, it is possible to limit the thermal bridges and improve the thermal properties of the junction.

7.
Molecules ; 24(9)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064131

RESUMO

The aim of this research was to optimize the separation and quantitative determination of nitrites and nitrates in human saliva. HPLC with UV absorption (HPLC/DAD) using a phosphatidylcholine column (IAM.PC.DD2 Regis HPLC) was applied in this assay. Nitrates were detected directly by their absorbance at 210 nm, whereas nitrites were detected after oxidation to nitrates by potassium permanganate at acidic conditions. The kinetics of the permanganate-nitrite reaction was measured chromatographically. The calibration graph for nitrates was linear in the range of 0.5-35 µg mL-1 with a correlation coefficient of 0.9999. The limit of detection was 4.56 ng mL-1. The calibration graph for nitrites (after oxidation to nitrates) was linear in the range of 0.5-15 µg mL-1 with a correlation coefficient of 0.9972. The limit of detection was 4.21 ng mL-1. The nitrate concentrations in the saliva samples were found in the range of 8.98-18.52 µg mL-1, whereas nitrite was in the range of 3.50-5.34 µg mL-1.


Assuntos
Nitratos/análise , Nitritos/análise , Fosfatidilcolinas/química , Saliva/química , Bioensaio/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Humanos , Limite de Detecção , Oxirredução , Permanganato de Potássio/química , Reprodutibilidade dos Testes
8.
Sensors (Basel) ; 18(11)2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30441820

RESUMO

The article presents the potential application of the time domain reflectometry (TDR) technique to measure moisture transport in unsaturated porous materials. The research of the capillary uptake phenomenon in a sample of autoclaved aerated concrete (AAC) was conducted using a TDR sensor with the modified construction for non-invasive testing. In the paper the basic principles of the TDR method as a technique applied in metrology, and its potential for measurement of moisture in porous materials, including soils and porous building materials are presented. The second part of the article presents the experiment of capillary rise process in the AAC sample. Application of the custom sensor required its individual calibration, thus a unique model of regression between the readouts of apparent permittivity of the tested material and its moisture was developed. During the experiment moisture content was monitored in the sample exposed to water influence. Monitoring was conducted using the modified TDR sensor. The process was additionally measured using the standard frequency domain (FD) capacitive sensor in order to compare the readouts with traditional techniques of moisture detection. The uncertainty for testing AAC moisture, was expressed as RMSE (0.013 cm³/cm³) and expanded uncertainty (0.01⁻0.02 cm³/cm³ depending on moisture) was established along with calibration of the applied sensor. The obtained values are comparable to, or even better than, the features of the traditional invasive sensors utilizing universal calibration models. Both, the TDR and capacitive (FD) sensor enabled monitoring of capillary uptake phenomenon progress. It was noticed that at the end of the experiment the TDR readouts were 4.4% underestimated and the FD readouts were overestimated for 12.6% comparing to the reference gravimetric evaluation.

9.
Waste Manag ; 76: 652-662, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29545073

RESUMO

The main goal of this study was to investigate the co-digestion of sewage sludge and mature landfill leachate pretreated through hydrodynamic cavitation. The process efficiency was analyzed from the aspects of organics removal, biogas production, kinetics and digestate quality. Energy efficiency of the overall treatment was evaluated as well. A dose of hydrodynamically cavitated leachate of 5% v/v was used as a substrate for co-digestion with sewage sludge at a hydraulic retention time of 20 days. This improved the kinetics, biogas production and corresponding yields, as well as digestate quality. Fourier transform infrared photoacoustic spectroscopy analysis seemed to indicate that no new toxic compounds were formed with co-digestion. The investigated two-stage treatment is recommended as a safe and cost-effective method of utilizing mature leachate.


Assuntos
Esgotos/química , Poluentes Químicos da Água/análise , Biocombustíveis , Reatores Biológicos , Hidrodinâmica
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