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1.
Microbiol Res ; 267: 127251, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36423546

RESUMO

Microorganisms degrade microplastics, but their potential is still not fully exploited, e.g., due to inadequate selection of microorganisms. We developed an effective selection method of microorganisms capable of polyethylene (PE) and polypropylene (PP) degradation and assessed the scale of polymer degradation by microbial populations. We isolated seven bacterial strains (three Priestia megaterium strains, Klebsiella pneumoniae, Pseudomonas fluorescens, Enterobacter ludwigii, Chryseobacterium sp.) and seven fungal strains (four Fusarium spp., two Lecanicillium spp. and Trichoderma sp.) with PE degradation potential, as well as seven bacterial strains (five Serratia marcescens and two Enterobacter spp.) and six fungal strains (four Aspergillus spp., Fusarium oxysporum and Penicillium granulatum) with PP degradation ability. Scanning electron microscopy (SEM) analysis confirmed the presence of a biofilm and revealed surface changes in both PE and PP pellets, but the greatest changes (microcracks and corrugations) were observed for PP incubated with bacteria. Fourier transform infrared (FTIR) spectroscopy confirmed the structural changes on the studied polymer surfaces. In conclusion, the isolation of plastic-degrading bacteria and fungi from waste landfills represents an effective strategy for the collection of microorganisms with high potential for PE and PP degradation. The bacteria and fungi revealed better potential for PP degradation and PE degradation, respectively.


Assuntos
Polietileno , Polipropilenos , Polietileno/química , Polietileno/metabolismo , Polipropilenos/metabolismo , Plásticos/metabolismo , Biodegradação Ambiental , Fungos/metabolismo
2.
Molecules ; 27(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36080242

RESUMO

The profiling and quantification of potentially toxic elements (PTEs) in honey from Poland was the main aim of this work. Due to the differences in botanical and geographical origin, 33 honey samples from various parts of Poland have been tested and compared to 12 samples taken from other countries, such as Australia, Bulgaria, Italy, Germany, Portugal, Romania and Turkey. The studied elements in honey samples were: As, Be, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, V and Zn. In most cases, the analyzed samples of honey were characterized by the moderate values of analyzed PTEs. Only a few samples contained higher concentrations of copper and manganese were noted. The presence of cadmium and lead in the level below the background equivalent concentrations was measured in the tested samples.


Assuntos
Mel , Metais Pesados , Oligoelementos , Cádmio/análise , Cobre , Monitoramento Ambiental , Mel/análise , Manganês , Metais Pesados/análise , Oligoelementos/análise
3.
Molecules ; 27(15)2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-35956972

RESUMO

Bladder cancer is one of most common types of cancer diagnosed in the genitourinary tract. Typical tests are costly and characterized by low sensitivity, which contributes to a growing interest in volatile biomarkers. Head space solid phase microextraction (SPME) was applied for the extraction of volatile organic compounds from urine samples, and gas chromatography time of flight mass spectrometry (GC×GC TOF MS) was used for the separation and detection of urinary volatiles. A cohort of 40 adult patients with bladder cancer and 57 healthy persons was recruited. Different VOC profiles were obtained for urine samples taken from each group. Twelvecompounds were found only in the samples from theBC group.The proposed candidate biomarkers are butyrolactone; 2-methoxyphenol; 3-methoxy-5-methylphenol; 1-(2,6,6-trimethylcyclohexa-1,3-dien-1-yl)-2-buten-1-one; nootkatone and 1-(2,6,6-trimethyl-1-cyclohexenyl)-2-buten-1-one.Since most of the studies published in the field are proving the potential of VOCs detected in urine samples for the screening and discrimination of patients with bladder cancer from healthy, but rarely presenting the identity of proposed biomarkers, our study represents a novel approach.


Assuntos
Neoplasias da Bexiga Urinária , Compostos Orgânicos Voláteis , Adulto , Biomarcadores , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Doenças Raras , Microextração em Fase Sólida/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Compostos Orgânicos Voláteis/análise
4.
Toxics ; 10(7)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35878263

RESUMO

Imidacloprid (IMI) is an extensively used neonicotinoid insecticide whose occurrence in the environment is a worldwide problem. Its sorption/transport properties are recognized as one of the key knowledge gaps hindering policymaking regarding its international routine monitoring in soils. Therefore, we studied IMI transport behaviour in Croatian Mediterranean soils using column experiments. Breakthrough curves were analysed using the two-site adsorption model and compared against dimethoate (DIM). Transport parameters were correlated to soil physicochemical properties. The results indicate that IMI shows a high degree of preference for soil organic matter over any other soil constituent. For IMI, the clay did not exhibit any sorption activity, while hematite did act as an active sorbent. Contrarily, hematite increased the leachability of DIM by blocking the active sorption sites on clay platelets. Both hematite and clay sorption acted as type-2 (i.e., rate-limiting) sites. In all soils, IMI exhibited lower short-term leachability than DIM. Combined with a body of data concerning other aspects of IMI environmental behaviour, the results indicate that the risk of accumulation of IMI in the soil is greater than the risk of contamination by leaching. Thus, continuous monitoring of IMI in soils should be incorporated into future soil health protection programs.

5.
Environ Monit Assess ; 193(10): 668, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34553268

RESUMO

Microplastics and nanoplastics have a range of impacts on the aquatic environment and present major challenges to their mitigation and management. Their transport and fate depend on their composition, form, and the characteristics of the receiving environment. We explore the spatial and temporal dynamics of plastic particles in the world's second-largest hypersaline lake, combining information from microscopic, thermal gravimetric, and fractional methods. Studies on microplastic and nanoplastic pollution in these important environments are scarce, and there is limited understanding of their dynamics and fate. Our results for Urmia Lake (Iran) in 2016 and 2019 show a discrepancy in the composition and quantity of microplastics measured in river tributaries to the lake and the lake itself, suggesting an active microplastic sink. Potential sink mechanisms in hypersaline lakes are explored. The present study indicates that microplastics have different transport mechanisms and fate in these extreme environments, compared to lake and ocean environments.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Lagos , Plásticos , Poluentes Químicos da Água/análise
6.
Int J Mol Sci ; 21(24)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352705

RESUMO

The aim of this study was to investigate isolated ß-lactoglobulin (ß-LG) from the whey protein isolate (WPI) solution using the column chromatography with SP Sephadex. The physicochemical characterization (self-association, the pH stability in various salt solutions, the identification of oligomeric forms) of the protein obtained have been carried out. The electrophoretically pure ß-LG fraction was obtained at pH 4.8. The fraction was characterized by the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/TOF MS) technique. The use of the HCCA matrix indicated the presence of oligomeric ß-LG forms, while the SA and DHB matrices enabled the differentiation of A and B isoforms in the sample. The impact of sodium chloride, potassium chloride, ammonium sulfate, and sodium citrate in dispersion medium on ß-LG electrophoretic stability in solution was also studied. Type of the dispersion medium led to the changes in the isoelectric point of protein. Sodium citrate stabilizes protein in comparison to ammonium sulfate. Additionally, the potential of capillary electrophoresis (CE) with UV detection using bare fused capillary to monitor ß-LG oligomerization was discussed. Obtained CE data were further compared by the asymmetric flow field flow fractionation coupled with the multi-angle light scattering detector (AF4-MALS). It was shown that the ß-LG is a monomer at pH 3.0, dimer at pH 7.0. At pH 5.0 (near the isoelectric point), oligomers with structures from dimeric to octameric are formed. However, the appearance of the oligomers equilibrium is dependent on the concentration of protein. The higher quantity of protein leads to the formation of the octamer. The far UV circular dichroism (CD) spectra carried out at pH 3.0, 5.0, and 7.0 confirmed that ß-sheet conformation is dominant at pH 3.0, 5.0, while at pH 7.0, this conformation is approximately in the same quantity as α-helix and random structures.


Assuntos
Eletroforese Capilar/métodos , Lactoglobulinas/química , Lactoglobulinas/isolamento & purificação , Espectrometria de Massas/métodos , Multimerização Proteica , Proteínas do Soro do Leite/química , Animais , Bovinos , Concentração de Íons de Hidrogênio , Lactoglobulinas/metabolismo
7.
Int J Occup Med Environ Health ; 33(2): 125-136, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-31942874

RESUMO

OBJECTIVES: This study analyzed the prevalence of new psychoactive substance (NPS) use in the analyzed group and compared demographic features and psychoactive substance profiles between the 2 subgroups (NPS users, non-NPS users). The secondary measure was used to determine the prevalence of psychiatric comorbidities in study group and to compare demographic features and psychoactive substance profiles between 2 subgroups (the F11-19 only diagnosed group and the F11-19 group with psychiatric comorbidities according to ICD-10). MATERIAL AND METHODS: A 12-month retrospective cross-sectional analysis of medical records compiled for adult psychiatric patients who had been admitted to the Regional Psychiatric Hospital in Olsztyn, Poland, in October 1, 2016 - September 30, 2017 was conducted. After analyzing the available medical records, 157 cases were included and analyzed. Data for the study were collected in a specially designed monitoring card from discharge reports, including data from psychiatric examinations, especially anamnesis. RESULTS: The most commonly declared psychoactive substances were amphetamine (AMF) - 54% and cannabinoids - 46%. The prevalence of NPS use in the study group was 34%. Inpatients taking NPS, as compared with non-NPS users, were younger and more often admitted to hospital through the Emergency Department. It was also found that NPS users more often took AMF or cannabinoids, and less frequently benzodiazepines (BDZ) or opioids. However, the taking of AMF, cannabinoids and BDZ was also age-dependent. CONCLUSIONS: The prevalence of psychiatric comorbidities in the study group was 9%. Inpatients with psychiatric comorbidities were older and took BDZ significantly more often than AMF. In addition, NPS use affects different groups, including a specific group as the analyzed sample, which shows a similar NPS use profile as different groups described in the literature. Int J Occup Med Environ Health. 2020;33(2):125-36.


Assuntos
Pacientes Internados/psicologia , Pacientes Internados/estatística & dados numéricos , Transtornos Mentais/induzido quimicamente , Psicotrópicos , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adulto , Comorbidade , Estudos Transversais , Usuários de Drogas/psicologia , Usuários de Drogas/estatística & dados numéricos , Feminino , Hospitais Psiquiátricos , Humanos , Masculino , Transtornos Mentais/epidemiologia , Polônia/epidemiologia , Prevalência , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
8.
J Sep Sci ; 43(3): 671-680, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31670460

RESUMO

Saponins in plant extracts were indirectly determined by estimation of the content of sapogenins. The first step of determination is extraction with high efficiency. One conventional extraction technique (maceration) and two modern ones (accelerated solvent extraction and supercritical fluid extraction) were compared. Methanol and ethanol were used as solvents or co-solvents. The results were supported by statistical analysis. Saponins were extracted from leaves, roots, and sprouts of Medicago sativa. Acid hydrolysis, purification, and determination by high-performance liquid chromatography with evaporative light scattering detector were used. The content of sapogenins was the highest in the roots. Smaller amounts of sapogenins were found in sprouts and the smallest ones in leaves. The main ingredient was medicagenic acid with mean concentration of 621.8 µg/g in roots, 456.7 µg/g in sprouts, and 471.3 µg/g in leaf extract. The highest content of sapogenins in extract was obtained after maceration with methanol; however, this method is nonselective in relation to biologically active compounds. Due to the possibility of using the obtained extracts with sapogenins in the cosmetic or pharmaceutical industry, the selection of extraction techniques and solvents is a very important aspect. Additionally, the chosen technique should be considered eco-friendly and consistent with the assumptions of "green chemistry."


Assuntos
Fermentação , Medicago sativa/química , Sapogeninas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia com Fluido Supercrítico , Sapogeninas/química , Solventes/química
9.
J Tissue Eng Regen Med ; 14(2): 334-346, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31825159

RESUMO

Keratin is a cytoskeletal scaffolding protein essential for wound healing and tissue recovery. The aim of the study was to evaluate the potential role of insoluble fur keratin-derived powder containing silver nanoparticles (FKDP-AgNP) in the allogenic full-thickness surgical skin wound model in diabetic mice. The scanning electron microscopy image evidenced that the keratin surface is covered by a single layer of silver nanoparticles. Data obtained from dynamic light scattering and micellar electrokinetic chromatography showed three fractions of silver nanoparticles with an average diameter of 130, 22.5, and 5 nm. Microbiologic results revealed that the designed insoluble FKDP-AgNP dressing to some extent inhibit the growth of Escherichia coli and Staphylococcus aureus. In vitro assays showed that the FKDP-AgNP dressing did not inhibit fibroblast growth or induce hemolysis. In vivo studies using a diabetic mice model confirmed biocompatible properties of the insoluble keratin dressings. FKDP-AgNP significantly accelerated wound closure and epithelization at Days 5 and 8 (p < .05) when compared with controls. Histological examination of the inflammatory response documented that FKDP-AgNP-treated wounds contained predominantly macrophages, whereas their untreated variants showed mixed cell infiltrates rich in neutrophils. Wound inflammatory response based on macrophages favors tissue remodeling and healing. In conclusion, the investigated FKDP-AgNP dressing consisting of an insoluble fraction of keratin, which is biocompatible, significantly accelerated wound healing in a diabetic mouse model.


Assuntos
Bandagens , Materiais Biocompatíveis/química , Diabetes Mellitus Experimental/metabolismo , Queratinas/química , Nanopartículas Metálicas/química , Prata/química , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Coloides/química , Citocinas/metabolismo , Escherichia coli , Inflamação , Cinética , Luz , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Transdução de Sinais , Pele/patologia , Staphylococcus aureus
10.
Lung Cancer ; 135: 123-129, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31446984

RESUMO

OBJECTIVE: Evaluation of the potential of combined multivariate chemometric methods for seeking markers of lung cancer. METHODS: Statistical methods such as Mann-Whitney U test, discriminant function analysis (DFA), factor analysis (FA) and artificial neural network (ANN) were applied to evaluate the obtained data from GC/MS analysis of exhaled breath. RESULTS: The total number of compounds identified by GC/MS in human breath was equal to 88. The statistical analysis indicates seven analytes which have the highest discriminatory power. Cross validation of the obtained model shows that the sensitivity was 80% and the specificity was 91.23%, while for the test group the sensitivity and specificity were both 86.36%. CONCLUSION: The application of combined statistical methods allowed to reduce the number of compounds to significant ones and indicates them as markers of lung cancer.


Assuntos
Biomarcadores Tumorais , Expiração , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Compostos Orgânicos Voláteis/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes Respiratórios , Análise Discriminante , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Curva ROC , Compostos Orgânicos Voláteis/metabolismo
11.
Environ Sci Pollut Res Int ; 26(30): 30988-30999, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31452126

RESUMO

Polychlorinated biphenyls (PCBs) in breast milk has been determined. Therefore, it was necessary to develop and adapt an analytical method to analyze PCB compounds. The whole procedure was applied to 31 breast milk samples, which were collected from Polish mothers. The QuEChERS method was optimized as a fast and cheap sample preparation method. The procedure allowed us to obtain recovery values between 96.46% and 119.98% with acceptable relative standard deviations (3.36-12.71%). Gas chromatography with mass spectrometry (GC-MS) was used for final determination. The method was validated using parameters such as linearity, limit of detection and quantification, intra-day precision, and reproducibility. The mean concentration of ∑iPCBs in this study was 30.94 ng/g of lipid. Assigned daily intake of PCBs was lower than the tolerable daily intake, which shows that the analyzed milk is safe to the infants. However, the monitoring of PCBs in milk is still important, and the QuEChERS method with GC-MS can be an effective tool for tracking organic impurities in breast milk.


Assuntos
Fracionamento Químico/métodos , Leite Humano/química , Bifenilos Policlorados/análise , Poluentes Ambientais/análise , Feminino , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Limite de Detecção , Polônia , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos
12.
Chemosphere ; 237: 124442, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31369900

RESUMO

Present studies facilitated testing the hypothesis that sediment fraction <20 µm contains different amounts of REEs. The potentially bioavailable rare earth elements (REEs) were determined in the following fractions of the surface sediments of the Vistula River: <5 µm, 5-10 µm, 10-20 µm, and total <20 µm. The attempt was made to fractionate the sediment by self-adjustable split-flow transport-thin fractionation channel operating in the full depletion mode (SPLITT-FFD-SA), which is a new concept and so far unused method for such purposes. All three fractions were separated in the expected particle size ranges. The collected fractions were analyzed with the laser diffraction particle size analyzer and the inductively coupled plasma - mass spectrometer (ICP-MS) to determine the size and the elemental composition. ∑REEs in the Vistula sediments declined from 123.41, through 112.59 to 95.22 mg kg-1 in fractions: 10-20 µm, 5-10 µm, <5 µm, respectively. Eleven, out of sixteen REEs, showed statistically significant declining trend in REEs content, with decreasing particle sizes of sediment fractions. Particularly exceptional was Er, whose content in <5 µm fraction was by 12-20% higher than in larger size fractions. Rare earth elements of the Vistula sediments are considerably enriched in the light rare earth elements (LREEs) relative to the heavy rare earth elements (HREEs), with the LREEs/HREEs ratio declining from 4.01 (10-20 µm) to 3.599 (<5 µm). The sequence of mass weighted REEs content in <20 µm size fraction was as follows: Ce > La > Nd > Y > Sc > Pr > Sm > Gd > Dy > Er > Yb > Eu > Tb > Ho > Tm > Lu.


Assuntos
Sedimentos Geológicos/química , Metais Terras Raras/análise , Rios/química , Peso Molecular , Tamanho da Partícula
13.
Chromatographia ; 81(8): 1213-1218, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30220732

RESUMO

Asymmetrical flow field-flow fractionation (AF4) and hollow-fiber flow field-flow fractionation (HF5) are techniques widely used in analytical, industrial and biological analyses. The main problem in all AF4 and HF5 analyses is sample loss due to analyte-membrane interactions. In this work the impact of liquid carrier composition on latex nanoparticles (NPs) separation in water and two different concentrations of NH4NO3 was studied. In AF4, a constant trend of decreasing the size of 60 and 121.9 nm particles induced by the ionic strength of the carrier liquid has been observed. In contrast, an agglomeration effect of the biggest 356 nm particles was observed when increasing ionic strength, which induced a significant drop of recovery to 35%. H5F provides better resolution and intensified peaks of NPs, but careful optimisation of system parameters is mandatory to obtain good separation.

14.
Environ Sci Pollut Res Int ; 25(29): 29734-29751, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30145758

RESUMO

Modeling (MONERIS) studies allowed calculation of nitrogen (N) and phosphorus (P) emission into the Vistula and Oder basins (Poland), and facilitated estimation of N and P retention in these catchments in 1995-2015. In the discussion of results, data of other authors were used in order to get an insight into N (1880-2015) and P emission (1955-2015) into the Oder basin. Population growth and agricultural intensification were responsible for respective 5.3-fold and 3.5-fold increase in N and P emission into the Oder basin, with the maximum (135,000 tons N year-1; 14,000 tons P year-1) observed at the turn of the 1980s/1990s. Pro-ecological activities during the economic transition period (since 1989) covered various sectors of the economy including agriculture, environmental protection related to, e.g., construction of a large number of waste water treatment plants (WWTPs). Consequently, in 1985-2015, the emission into the Oder basin decreased from the abovementioned maxima to 94,000 tons N year-1 and to 5000 tons P year-1, whereas in 1995-2015, the emission into the Vistula basin decreased from 170,000 to 140,000 tons N year-1 and from 14,200 to 10,600 tons P year-1. In 1995-2015, groundwater, tile drainage, and WWTPs played a key role in N emission, while erosion, overland flow, WWTPs, and urban areas played a predominant role in P emission. The relative shares of nutrient emission pathways in overall N and P emission were considerably changing over time. Extreme weather conditions have a great impact on increased (floods) or decreased (droughts) nutrient emission; particularly, N emission is susceptible to variable weather conditions. In total, approximately 91,000 tons of N and 7600 tons of P were retained annually in the river basins.


Assuntos
Monitoramento Ambiental/métodos , Modelos Teóricos , Nitrogênio/análise , Fósforo/análise , Rios/química , Poluentes Químicos da Água/análise , Agricultura , Sistemas de Informação Geográfica , Água Subterrânea/química , Polônia , Águas Residuárias/química , Purificação da Água/métodos
15.
Anal Bioanal Chem ; 410(11): 2837-2847, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29616293

RESUMO

Asymmetric flow field-flow fractionation coupled with use of ultraviolet-visible, multiangle light scattering (MALLS), and dynamic light scattering (DLS) detectors was used for separation and characterization of biologically synthesized silver composites in two liquid compositions. Moreover, to supplement the DLS/MALLS information, various complementary techniques such as transmission electron spectroscopy, Fourier transform infrared spectroscopy, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) were used. The hydrodynamic diameter and the radius of gyration of silver composites were slightly larger than the sizes obtained by transmission electron microscopy (TEM). Moreover, the TEM results revealed the presence of silver clusters and even several morphologies, including multitwinned. Additionally, MALDI-TOF MS examination showed that the particles have an uncommon cluster structure. It can be described as being composed of two or more silver clusters. The organic surface of the nanoparticles can modify their dispersion. We demonstrated that the variation of the silver surface coating directly influenced the migration rate of biologically synthesized silver composites. Moreover, this study proves that the fractionation mechanism of silver biocolloids relies not only on the particle size but also on the type and mass of the surface coatings. Because silver nanoparticles typically have size-dependent cytotoxicity, this behavior is particularly relevant for biomedical applications. Graphical abstract Workflow for asymmetric flow field-flow fractionation of natural biologically synthesized silver nanocomposites.


Assuntos
Fracionamento por Campo e Fluxo/métodos , Nanopartículas Metálicas/química , Prata/química , Biomimética , Difusão Dinâmica da Luz/métodos , Hidrodinâmica , Nanopartículas Metálicas/ultraestrutura , Nanotecnologia , Tamanho da Partícula , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier
16.
J Chromatogr A ; 1552: 67-72, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29673764

RESUMO

The article contains a description of both the mathematical modeling of particles separation in self-adjustable channel for Split Flow Thin Cell Fractionation (SPLITT), and the channel design concept. The channel is designed to work in full feed depletion mode (FFD-SPLITT). By using different diameters of outlets, the channel has the ability to self-adjust the flow rates at the outlets. Moreover, in order to increase the throughput of the sample only one splitter, positioned at the end of the separation cell, was used. Channel construction, which is based on the SPLITT cell developed by J.C. Giddings, has an innovative approach. All the parameters affecting the separation are automatically tuned through modification of the channel structure, and that in turn stems from mathematical model based on fluid mechanics.


Assuntos
Modelos Teóricos , Cromatografia/métodos , Tamanho da Partícula
17.
Anal Bioanal Chem ; 410(5): 1571-1582, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29368148

RESUMO

Endometrial cancer is one of the most commonly diagnosed cancers in women. The search for factors that contribute to the development of cancer cells in reproductive organs should involve the detection of xenoestrogens, in particular zearalenone (ZEA) and its metabolites. Xenoestrogens are endocrine disruptors-ZEA and its metabolites are structurally similar to estrogens (macrocyclic lactone ring) and show high affinity for estrogen receptors. This study proposes a new method for the preparation of samples of human tissues with endometrial cancer by the use of the QuEChERS technique. Analytical parameters such as centrifugation temperature, extraction solvent, and adsorbents were modified to obtain satisfactory recovery for ZEA (R = 82.6%, RSD = 2.9%) and one of its metabolites, α-zearalenol (R = 50.1%, RSD = 3.2%). High-performance liquid chromatography (HPLC) with fluorescence detection and tandem mass spectrometry (LC-QTOF-MS) were used for the identification and quantitative determination of the analyzed compounds. The developed procedure was applied for analyses of human tissues with endometrial cancer. The presence of α-zearalenol was detected in 47 out of the 61 examined tissue samples. Graphical Abstract Methodology for isolation and identification of zearalenone and its major metabolites.


Assuntos
Neoplasias do Endométrio/química , Zearalenona/química , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Espectrometria de Massas em Tandem/métodos
18.
PLoS One ; 12(8): e0184034, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28859143

RESUMO

Squamous cell carcinoma of the skin is the second most common cutaneous malignancy. Despite various available treatment methods and advances in noninvasive diagnostic techniques, the incidence of metastatic cutaneous squamous cell carcinoma is rising. Deficiency in effective preventive or treatment methods of transformed keratinocytes leads to necessity of searching for new anticancer agents. The present study aims to evaluate the possibility of using wool hydrolysates as such agents. Commercially available compounds such as 5-fluorouracil, ingenol mebutate, diclofenac sodium salt were also used in this study. The process of wool degradation was based on chemical pre-activation and enzymatic digestion of wool. The effect of mentioned compounds on cell viability of squamous carcinoma cell line and healthy keratinocytes was evaluated. The obtained data show a significantly stronger effect of selected wool hydrolysates compared to commercial compounds (p<0.05) on viability of cells. The wool hydrolysates decreased squamous cell carcinoma cells viability by up to 67% comparing to untreated cells. These results indicate bioactive properties of wool hydrolysates, which affect the viability of squamous carcinoma cells and decrease their number. We hypothesize that these agents may be used topically for treatment of transformed keratinocytes in actinic keratosis and invasive squamous skin cancer in humans.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Hidrolisados de Proteína/química , Neoplasias Cutâneas/tratamento farmacológico , Lã/química , Animais , Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Diclofenaco/farmacologia , Diterpenos/farmacologia , Fluoruracila/farmacologia , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/patologia , Hidrolisados de Proteína/farmacologia , Neoplasias Cutâneas/patologia
19.
J Sep Sci ; 40(21): 4152-4159, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28859247

RESUMO

The surface excess adsorption isotherms of water, acetonitrile, and methanol from binary hydro-organic mobile phases were investigated on nine home-made stationary phases with chemically bonded amino acids, dipeptides, and tripeptides using the dynamic minor disturbance method. The stationary phases were modified by the following amino acids: glycine, alanine, phenylalanine, leucine, and aspartic acid. We investigated the influence of the type of immobilized amino acids, in particular their different side chains, on the solvent adsorption. The interpretation of solvation phenomena shows significant accumulation of investigated solvents on the adsorbent surface according to their hydrophilic or hydrophobic properties. Moreover, the accumulated amount was dependent on the length and type of amino acid sequences bonded to the silica surface. Stationary phases with bonded amino acids and peptides show stronger water and acetonitrile adsorption in contrast to the stationary phase modified with aminopropyl groups-a support for the synthesis. The comparison of water and acetonitrile adsorption as well as a data obtained with the two-site adsorption model reveal and confirm the heterogeneity of chemically bonded phases. As a consequence of performed investigations, the classification of tested stationary phases for the potential usage in particular high-performance liquid chromatography mode was also accomplished.


Assuntos
Aminoácidos/química , Peptídeos/química , Dióxido de Silício , Adsorção , Cromatografia Líquida de Alta Pressão , Solventes
20.
J AOAC Int ; 100(6): 1681-1693, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28791945

RESUMO

Medicago sativa L. (M. sativa) is a source of many valuable secondary metabolites. Extraction yield and the concentration of phenolics, flavonoids, and saponins, as well as antioxidant potential were determined in extracts from different parts of M. sativa obtained using extraction methods such as maceration, ultrasound-assisted extraction (UAE), accelerated solvent extraction (ASE), and supercritical fluid extraction (SFE). The concentrations of the listed groups of compounds were spectrophotometrically determined and confirmed by HPLC-MS. The results showed that ASE of flowers with 70% ethanol (EtOH) provided the highest yield of extraction (47.5 ± 4.0%), whereas the lowest yield was obtained in stems (4.0 ± 0.2%). The 70% EtOH extract from flowers showed the highest phenolic content [48.4 ± 4.6 mg gallic acid equivalents/g dry matter (DM)], as well as the highest antioxidant activity. The highest total flavonoid content (139.0 ± 7.1 mg rutin equivalents/g DM) was observed in the extract from leaves obtained through SFE. This extract was also especially rich in saponins [622.2 ± 30.3 mg oleanolic acid equivalents (OAE)/g DM]. However, the lowest compound content was observed in maceration extracts from stems (54.6 ± 27.0 mg OAE/g DM). The results suggest that EtOH extracts from alfalfa flowers and SFE extracts from M. satvia leaves, especially, may serve as potential sources of natural antioxidants for nutraceuticals, food additives, and cosmetic ingredients.


Assuntos
Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fracionamento Químico/métodos , Medicago sativa/química , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico , Etanol/química , Flavonoides/análise , Flores/química , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/química , Saponinas/análise , Saponinas/isolamento & purificação , Sementes/química , Solventes , Ultrassom/métodos
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