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1.
Biomedicines ; 12(2)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38397889

RESUMO

BACKGROUND: Multiple drug-delivery systems obtained by loading nanoparticles (NPs) with different drugs that have different physicochemical properties present a promising strategy to achieve synergistic effects between drugs or overcome undesired effects. This study aims to develop a new NP by loading quercetin (Que) and valproic acid (VPA) into chitosan. In this context, our study investigated the antioxidant activities of chitosan NPs loaded with single and dual drugs containing Que against oxidative stress. METHOD: The synthesis of chitosan NPs loaded with a single (Que or VPA) and dual drug (Que and VPA), the characterization of the NPs, the conducting of in vitro antioxidant activity studies, and the analysis of the cytotoxicity and antioxidant activity of the NPs in human neuroblastoma SH-SY5Y cell lines were performed. RESULT: The NP applications that protected cell viability to the greatest extent against H2O2-induced cell damage were, in order, 96 µg/mL of Que-loaded chitosan NP (77.30%, 48 h), 2 µg/mL of VPA-loaded chitosan NP (70.06%, 24 h), 96 µg/mL of blank chitosan NP (68.31%, 48 h), and 2 µg/mL of Que- and VPA-loaded chitosan NP (66.03%, 24 h). CONCLUSION: Our study establishes a successful paradigm for developing drug-loaded NPs with a uniform and homogeneous distribution of drugs into NPs. Chitosan NPs loaded with both single and dual drugs possessing antioxidant activity were successfully developed. The capability of chitosan NPs developed at the nanometer scale to sustain cell viability in SH-SY5Y cell lines implies the potential of intranasal administration of chitosan NPs for future studies, offering protective effects in central nervous system diseases.

2.
Environ Sci Pollut Res Int ; 31(2): 2466-2480, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38066275

RESUMO

Minerals such as calcium carbonate, which is prevalent in marble and limestone, are present naturally in rocks. Both physicochemical processes and microbial processes can result in the creation of calcium carbonate in nature, as is well documented. In this study, microbiologically induced calcite precipitation potential of three different Travertine-type water sources (Pamukkale Travertine Spring (PTS), Pamukkale Travertine Terraces (PTT), and Red Travertine of Karahayit (RTK)) using three different incubation media (NB, NB3, and ATCC1832) were investigated. After enrichment with ATCC1832 media, urease assays were positive for all of the microbial sources. The PTS and PTT were cultured with ATCC1832 medium for 48 h, which showed the best results for urease activity and microbial growth among other samples. Metagenome analyses indicated that PTT enriched with ATCC1832 media contains > 99% Firmicutes, while PTS enriched with ATCC1832 contains > 99% Proteobacteria at the Phylum level. Results from SEM-EDX and XRD analysis revealed that calcite and/or vaterite were the minerals that emerged from the mineralization of the PTS and PTT during incubation. The type of calcium carbonate crystals tended to change from one form to another when the incubation period extends from 72 to 120 h. Both the PTS and the PTT were able to precipitate calcite within the sand column. However, the bacteria from the PTT (26% CaCO3) outperformed those from the PTS (18% CaCO3) in terms of calcium carbonate deposition on the 21st day of incubation.


Assuntos
Carbonato de Cálcio , Areia , Carbonato de Cálcio/química , Urease , Minerais , Bactérias , Precipitação Química
3.
J Environ Manage ; 351: 119899, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159310

RESUMO

This paper proposes a novel targeted blend of machine learning (ML) based approaches for controlling wastewater treatment plant (WWTP) operation by predicting distributions of key effluent parameters of a biological nutrient removal (BNR) process. Two years of data were collected from Plajyolu wastewater treatment plant in Kocaeli, Türkiye and the effluent parameters were predicted using six machine learning algorithms to compare their performances. Based on mean absolute percentage error (MAPE) metric only, support vector regression machine (SVRM) with linear kernel method showed a good agreement for COD and BOD5, with the MAPE values of about 9% and 0.9%, respectively. Random Forest (RF) and EXtreme Gradient Boosting (XGBoost) regression were found to be the best algorithms for TN and TP effluent parameters, with the MAPE values of about 34% and 27%, respectively. Further, when the results were evaluated together according to all the performance metrics, RF, SVRM (with both linear kernel and RBF kernel), and Hybrid Regression algorithms generally made more successful predictions than Light GBM and XGBoost algorithms for all the parameters. Through this case study we demonstrated selective application of ML algorithms can be used to predict different effluent parameters more effectively. Wider implementation of this approach can potentially reduce the resource demands for active monitoring the environmental performance of WWTPs.


Assuntos
Algoritmos , Aprendizado de Máquina , Nutrientes , Máquina de Vetores de Suporte
4.
Environ Monit Assess ; 196(1): 21, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38060054

RESUMO

Dairy industry wastewater can be considered as an important source of pollution due to its high amounts and pollutant concentrations. Anaerobic treatment is seen as a suitable alternative over aerobic treatment which requires huge aeration systems. Biochemical methane potential (BMP) testing is a widely applied technique for estimating the performance of anaerobic digesters and still has no clear alternative. In the study, the biochemical methane potential change was investigated by mixing dairy wastewater with different co-substrates (cattle manure, chicken manure and slaughterhouse wastewater) at different rates. The highest biogas potential per gram of chemical oxygen demand added (CODadded) was determined as 574 mLbiogas in a mixture of 74% dairy wastewater + 2% chicken manure + 24% slaughterhouse wastewater inoculated with granular sludge. The highest methane potential was determined as 340 mLCH4 in the same co-substrate mixture inoculated with anaerobic sludge. In recent years, mathematical modeling offers an alternative to BMP tests and many different models are used for this purpose. In the study, six different mathematical models were used to simulate the BMP results, and the highest correlation coefficient in almost all mixtures ranged from 0.900 to 0.997 with the Modified Gompertz equation and Fitzhugh models.


Assuntos
Esgotos , Águas Residuárias , Animais , Bovinos , Anaerobiose , Metano , Biocombustíveis , Esterco , Reatores Biológicos , Monitoramento Ambiental
5.
J Environ Health Sci Eng ; 21(1): 123-132, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37159727

RESUMO

Fractionation of active biomass in a five-stage Bardenpho process was accomplished using an MS Excel wastewater treatment plant modeling tool based on Activated Sludge Model No. 3 extended with a bio-P module. The biomass fractions within the treatment system were predicted as autotrophs, ordinary heterotrophs, and phosphorus accumulating organisms (PAOs). Several simulations were performed in a Bardenpho process using various C/N/P ratios in primary effluent. Biomass fractionation was obtained from steady-state simulation results. The results suggest that the mass percentage of autotrophs, heterotrophs, and PAOs in active biomass range from 1.7 to 7.8%, 5.7-69.0%, and 23.2-92.6%, respectively, depending on characteristics of primary effluent. Results of principal component analysis showed that TKN/COD ratio in primary effluent determines the population of autotrophs and ordinary heterotrophs whereas PAO population is mainly a function of TP/COD ratio.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33805955

RESUMO

Although conventional biological treatment plants can remove basic pollutants, they are ineffective at removing recalcitrant pollutants. Membrane bioreactors contain promising technology and have the advantages of better effluent quality and lower sludge production compared to those of conventional biological treatment processes. In this study, the removal of pharmaceutical compounds by membrane bioreactors under different solid retention times (SRTs) was investigated. To study the effect of SRT on the removal of emerging pharmaceuticals, the levels of pharmaceuticals were measured over 96 days for the following retention times: 20, 30, and 40-day SRT. It was found that the 40-day SRT had the optimum performance in terms of the pharmaceuticals' elimination. The removal efficiencies of the chemical oxygen demand (COD) for each selected SRT were higher than 96% at steady-state conditions. The highest degradation efficiency was observed for paracetamol. Paracetamol was the most removed compound followed by ranitidine, atenolol, bezafibrate, diclofenac, and carbamazepine. The microbial community at the phylum level was also analyzed to understand the biodegradability of pharmaceuticals. It was noticed that the Proteobacteria phylum increased from 46.8% to 60.0% after 96 days with the pharmaceuticals. The Actinobacteria class, which can metabolize paracetamol, carbamazepine, and atenolol, was also increased from 9.1% to 17.9% after adding pharmaceuticals. The by-products of diclofenac, bezafibrate, and carbamazepine were observed in the effluent samples.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Biodegradação Ambiental , Reatores Biológicos , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água/análise
8.
Saudi Pharm J ; 27(6): 846-858, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31516327

RESUMO

We report the synthesis and applications of a novel N-doped graphene quantum dots (GQDs) using hydrothermal reaction between citric acid and p-aminophenol. The synthesized N-doped GQDs have been characterized physico-chemically and evaluated its antioxidant, antimicrobial, DNA binding and cleavage activities. siRNA loading studies were performed and their effects on cells were evaluated. Obtained results indicate that monodisperse solution of N-doped GQDs has been obtained with particles size ca. ∼10.9 ±â€¯1.3 nm. UV-Vis spectroscopy studies of the interactions between the N-doped GQDs and calf thymus DNA (CT-DNA) showed that the compound interact with CT-DNA via both intercalative and electrostatic binding. The DNA cleavage study showed that the N-doped GQDs cleaved DNA without any external agents. The antioxidant activity of N-doped GQDS was very active when compared to BHT. As the concentration of the compound increased, the antioxidant activity also increased. Cell viability assay demonstrated that the Ndoped GQDs showed cell viability (70%) when the concentration reached 200 µg/mL for A549 and also MDA-MB-231, 150 µg/mL for NIH-3T3 cell lines at 24 h incubation. N-doped GQDs were coated with Eudragit RS 100 and EphA2-siRNA was loaded. As a result of the studies on these formulations, it was concluded that there may be significant effects on A549 cells. The microscopy results revealed that N-doped GQDs was quickly internalized into the cell. Our novel N-doped-GQDs with siRNA are candidate for in situ tumor suppression via DNA and mRNA breakage.

9.
Environ Monit Assess ; 191(2): 60, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30631961

RESUMO

Superoxide dismutase (SOD) is one of the antioxidant defense enzymes in mussels and converts the superoxide anion into hydrogen peroxide and this enzyme is used as biomarkers of oxidative damage. As well as many topics in ecology, stable isotopes are also signature for organic and heavy metal pollution in aquatic ecosystems. This study aims to compare the stable carbon and nitrogen values of different mussel tissues and the changes on the SOD values of the same tissues in order to understand the relationship between two mechanisms of bioindicator processes of physiological response of mussel to pollution. The changes in SOD activity in the gill, hepatopancreas, and mantle tissues of Mytilus galloprovincialis with δ13C and δ15N isotopes were assessed in two locations (Kepez and Güzelyali) in Çanakkale. The SOD values of mussel samples were found as the gill > hepatopancreas > mantle collected from Kepez and the gill > hepatopancreas collected from Güzelyali. There were no significant differences among the mean SOD values of different tissues. There was enrichment both in nitrogen and carbon isotope values of hepatopancreas tissues both in Kepez and Güzelyali samples. There was a negative correlation between both isotope values and SOD values of samples. As well as SOD values, the isotopic composition of particularly hepatopancreas tissue is a good indicator for evaluation of pollution.


Assuntos
Monitoramento Ambiental/métodos , Mytilus/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biomarcadores/metabolismo , Isótopos de Carbono , Poluição Ambiental , Brânquias/química , Hepatopâncreas/química , Metais Pesados/análise , Mytilus/química , Superóxido Dismutase , Poluentes Químicos da Água/análise
10.
Clin Respir J ; 11(4): 506-513, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26260848

RESUMO

OBJECTIVES: Cognitive impairment is common among patients with obstructive sleep apnea syndrome (OSAS). In this study, we aimed to investigate the effect of continuous positive airway pressure (CPAP) therapy on serum insulin-like growth factor-1 (IGF-1) levels and cognitive functions in patients with OSAS. PATIENT/METHODS: Thirty-three patients with newly diagnosed OSAS and 17 healthy-control subjects enrolled in the study. All individuals completed the mini-mental state examination (MMSE) to evaluate cognitive function. Blood samples were taken at the end of the polysomnography in the morning and the same procedures were repeated 3 months after starting CPAP treatment. RESULTS: In the OSAS group, the baseline MMSE score was 23.5 ± 3.6, and serum IGF-1 level was 79.1 ± 36.1 ng/mL. Both values were significantly lower compared with the control group (mean MMSE score = 28.1 ± 1.4, P = 0.0001; mean serum IGF-1 level = 147.1 ± 49.1 ng/mL, P < 0.0001). Three months after CPAP treatment, OSAS patients showed a significant improvement in MMSE scores (26.5 ± 2.8, P = 0.0001) and serum IGF-1 level (129.1 ± 58.2, P = 0.0001). In contrast, baseline and third-month measurements for IGF-1 levels and MMSE scores were not significantly different in the control group. CONCLUSIONS: The results indicate that effective CPAP therapy in OSAS patients leads to significant improvement in cognitive functions and IGF-1 even in a short-term follow-up. Cognitive function assessment might be a part of evaluation in OSAS patients.


Assuntos
Cognição/fisiologia , Pressão Positiva Contínua nas Vias Aéreas/métodos , Fator de Crescimento Insulin-Like I/análise , Apneia Obstrutiva do Sono/terapia , Adulto , Índice de Massa Corporal , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Polissonografia , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico , Resultado do Tratamento
11.
Bioorg Med Chem ; 24(21): 5592-5601, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27658791

RESUMO

An amino acid based and bidentate Schiff base, (E)-methyl 2-((2-oxonaphthalen-1(2H)-ylidene)methylamino)acetate (ligand), was synthesized from the reaction of glycine-methyl ester hydrochloride with 2-hydroxy-1-naphthaldehyde. Characterization of the ligand was carried out using theoretical quantum-mechanical calculations and experimental spectroscopic methods. The molecular structure of the compound was confirmed using X-ray single-crystal data, NMR, FTIR and UV-Visible spectroscopy, which were in good agreement with the structure predicted by the theoretical calculations using density functional theory (DFT). Antimicrobial activity of the ligand was investigated for its minimum inhibitory concentration (MIC) to several bacteria and yeast cultures. UV-Visible spectroscopy studies also shown that the ligand can bind calf thymus DNA (CT-DNA) electrostatic binding. In addition, DNA cleavage study showed that the ligand cleaved DNA without the need for external agents. Energetically most favorable docked structures were obtained from the rigid molecular docking of the compound with DNA. The compound binds at the active site of the DNA proteins by weak non-covalent interactions. The colorimetric response of the ligand in DMSO to the addition of equivalent amount of anions (F-, Br-, I-, CN-, SCN-, ClO4-, HSO4-, AcO-, H2PO4-, N3- and OH-) was investigated and the ligand was shown to be sensitive to CN- anion.


Assuntos
Acetatos/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Cianetos/análise , Naftalenos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Acetatos/síntese química , Acetatos/química , Animais , Ânions/análise , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Bovinos , DNA/efeitos dos fármacos , Clivagem do DNA , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Naftalenos/síntese química , Naftalenos/química , Teoria Quântica , Eletricidade Estática , Relação Estrutura-Atividade
12.
Mol Biol Rep ; 40(11): 6189-94, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24057245

RESUMO

The aim of this study is to evaluate the role of IL28B rs12979860 polymorphism on pegylated interferon (peg IFN) and oral antiviral treatment in chronic hepatitis B (CHB) patients and to investigate the relationship between the severities of illness with this polymorphism. 74 CHB patients who are received treatment, 61 asymptomatic carriers and 40 healthy controls were recruited in this study. Genomic DNA of controls and patients were extracted from whole blood using High Pure PCR Template Preparation Kit (Roche, Mannheim, Germany) according to the manufacturer's instructions and stored at 4 °C. Genotype distribution of the IL-28B polymorphism at position -3176C/T (rs12979860) (LightMix Kit IL28B, Cat.-No. 40-0588-32 TIB MOLBIOL, Berlin, Germany) was detected by real time PCR (Roche Diagnostics, Manheim, Germany). Thirty of the patients with CHB received peg IFN-α treatment. There were no significant difference between groups by means of age, gender and IL28B rs12979860 polymorphism (p = 0.122, p = 0.07, p = 0.376 respectively). Patients with chronic hepatitis were categorized as grade and stage (minimal, moderate and severe) and then were analyzed for the polymorphism. There was no effect of IL28B -3176 C/T polymorphism on severity of illness (p = 0.293 for grade, p = 0.911 for stage). When the CHB treatment monitored in different time arrivals (beginning, 3th, 6th and 12th months of the treatment) in order to see if there was an effect on virological and biological response none of the genotypes of IL28B -3176C/T polymorphism altered peg IFN or oral antiviral treatment process. There are conflicting results about the role of IL28B rs12979860 polymorphism in CHB in the literature. In this preliminary study, we observed that IL28B rs12979860 polymorphism was not related with severity of illness and also was not effective on treatment response.


Assuntos
Hepatite B Crônica/genética , Interleucinas/genética , Polimorfismo Genético , Adulto , Idoso , Alelos , Antivirais/uso terapêutico , Feminino , Genótipo , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Humanos , Interferons , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
13.
Environ Technol ; 33(7-9): 801-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22720403

RESUMO

In this study, the electrocoagulation process was evaluated as a pretreatment process for olive mill wastewaters. Aluminium (Al) and iron (Fe) electrodes, several contact times and 0.5, 1 and 2 A currents were used to compare chemical oxygen demand (COD) removal efficiencies for each case. The optimum contact time and current were 45 minutes and 1 A, respectively, which resulted in a COD removal of 58.7% with an Al electrode. Experimental data from distinct operational conditions were used to fit a model for COD removal efficiencies. Energy consumption was also predicted. Under optimum operational conditions, the treatment cost was approximately Euro 0.13 kg(-1) CODremoved and Euro 4.41 m(-3). The results showed that the electrocoagulation process was a cost-effective method for the pretreatment of olive mill wastewaters.


Assuntos
Resíduos Industriais , Olea , Eliminação de Resíduos Líquidos/economia , Poluição da Água/prevenção & controle , Análise da Demanda Biológica de Oxigênio , Técnicas Eletroquímicas , Modelos Químicos , Eliminação de Resíduos Líquidos/métodos
14.
J Insect Physiol ; 51(4): 379-84, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15890180

RESUMO

Adult male crayfish Procambarus clarkii exist in two morphotypes. They continue to molt as adults, switching between Form Is and Form IIs. Form Is are primary reproductive types, with large chelae and spines on the ischiopodites of the third and fourth pair of walking legs. Form IIs are non-reproductive types with smaller chelae and no spines on the ischiopodites. We investigated the hormonal control of these transitions in two ways, by eyestalk ablation and by methyl farnesoate (MF) treatments. Eyestalk ablation accelerates molting and increases MF levels in the blood. MF is a hormone that regulates both reproduction and morphogenesis. MF concentrations were determined in two ways. The hemolymph samples were extracted first, then purified, using normal phase HPLC. The fractions containing MF were collected and analyzed for MF concentration, utilizing both internal and external standards by GC/MS. The other hemolymph samples were analyzed from individual animals by HPLC. The concentrations of ecdysteroids were determined by radioimmunoassay. In the control animals, 4 out of 4 untreated Form I males molted into Form II, while 6 out of 7 Form IIs molted into Form Is. Eight of 8 ablated Form Is molted into Form IIs as expected, while 5 of 5 ablated Form IIs molted into Form IIs, instead of Form Is. MF treatment of intact animals resulted in 6 of 7 Form Is becoming Form IIs and 5 of 6 Form IIs becoming Form IIs. These results were highly significant in comparison of Form I and IIs in each treatment (eyestalk intact, eyestalk ablated and eyestalk intact with MF) by a chi square analysis, P = 0.006, P < 0.0005, and P = 0.013, respectively. MF premolt blood levels suggested that Form IIs were produced in the presence of 1.3 ng/ml MF, while Form Is result from MF levels less than 0.5 ng/ml. Since both eyestalk ablation and MF treatment resulted in the failure of Form IIs becoming Form Is, it was concluded that the control of morphogenesis of primary reproductives (Form Is) depends on a low level of MF prior to the molt, while Form IIs are formed in the presence of increased levels of MF.


Assuntos
Astacoidea/crescimento & desenvolvimento , Ácidos Graxos Insaturados/fisiologia , Morfogênese/fisiologia , Animais , Astacoidea/metabolismo , Olho/metabolismo , Ácidos Graxos Insaturados/metabolismo , Masculino , Muda/fisiologia
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