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1.
J Environ Manage ; 360: 121072, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38733851

RESUMO

Amoxicillin, a member of the penicillin family, is primarily utilized for the treatment of various bacterial infections affecting ears, nose, throat, urinary tract, and skin. Given its widespread application in medicine, agriculture, environment, and food industry, the precise and sensitive detection of amoxicillin is important. This study introduces a novel approach to developing a sensitive and selective fluorescent aptasensor relying on fluorescence resonance energy transfer (FRET) for the specific detection of amoxicillin. The carboxyfluorescein-labeled aptamer serves as a energy donor, while MXene functions as an energy acceptor, and acting as a quencher. To achieve optimal detection efficiency, a dual optimization strategy utilizing RSM-CCD and ANN-GA was used to fine-tune experimental conditions. The fluorescence measurements revealed an expansive linear range extending from 100 to 2400 ng mL-1, accompanied by an exceptionally low detection limit of 1.53 ng mL-1. Additionally, it shows an excellent selectivity towards amoxicillin over other antibiotics commonly found in water matrices. The aptasensor demonstrates good stability and reproducibility; effectiveness of the aptasensor was validated by testing in real water samples. This remarkable sensitivity and broad dynamic range affirm the efficacy aptasensor in accurately detecting varying concentrations of amoxicillin in wastewater bodies.

2.
Chemosphere ; 313: 137427, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36455660

RESUMO

The present work aims the synthesis of a novel, low cost, and environmentally friendly PANI/PVA-CuNi composite by chemical oxidative polymerization of aniline monomer and polyvinyl alcohol (PVA) as film matrix; several percentages of copper (Cu) and Nickel (Ni) were used. UV-Visible spectroscopy, FTIR, SEM-EDX, and TGA were used to characterize the nanocomposites. While PANI/PVA-CuNi nanocomposites were investigated in adsorption experiments of methylene blue (MB) under different controlled conditions (time reaction, adsorbent dosage, initial dye concentration, stirring speed, temperature, and pH of the medium) also various kinetic models were employed to evaluate the efficiency of the adsorption. The results revealed that the10 mg of PANI/PVA-Cu50Ni50 and PANI/PVA-Ni composites Catalyst removed (94% and 93% of methylene blue in 180 min respectively at 10-5 M initial concentration of dye, pH of 13, stirring speed of 150 rpm, the temperature of 301 k. the kinetics data were properly fitted with the pseudo second-order model with a correlation coefficient of 0.98262 and 0.95881 using PANI/PVA-Cu50Ni50 and PANI/PVA-Ni, respectively.


Assuntos
Álcool de Polivinil , Poluentes Químicos da Água , Álcool de Polivinil/química , Azul de Metileno/química , Poluentes Químicos da Água/química , Temperatura , Corantes/química , Adsorção , Cinética , Concentração de Íons de Hidrogênio
3.
Environ Res ; 214(Pt 3): 114026, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35977588

RESUMO

Azithromycin (AZM), an antibacterial considered one of the most consumed drugs, especially during the period against the Covid 19 pandemic, and it is one of the persistent contaminants that can be released into aquatic ecosystems. The purpose of this study is to determine the efficacy of a Fenton-like process (chlorine/iron) for the degradation of AZM in an aqueous medium by determining the impact of several factors (the initial concentration of (FeSO4, NaClO, pollutant), and the initial pH) on the degradation rate. The Response Surface Methodology (RSM) based on the Box-Wilson design as well as the Artificial Neural Network (ANN) modeling combined with a genetic algorithm (GA) approaches were used to determine the optimal levels of the selected variables and the optimal rate of degradation. The quadratic model of multi-linear regression developed indicated that the optimal conditions were a concentration of chlorine of 600 µM, the concentration of AZM is 32.8 mg/L, the mass of the catalyst FeSO4 is 3.5 mg and a pH of 2.5, these optimal values gave a predicted and experimental yield of 64.05% and 70% respectively, the lack of fit test in RSM modeling (F0 = 3.31 which is inferior to Fcritic (0.05, 10.4) = 5.96) indicates that the true regression function is not linear therefore, the ANN-GA modeling as non-linear regression indicated that the optimal conditions were a concentration of chlorine of 256 µM, the concentration of AZM is 5 mg/L, the mass of the catalyst FeSO4 is 9.5 mg and a pH of 2.8, these optimal values gave a predicted and experimental yield of 79.69% and close to 80% respectively, Furthermore, biotoxicity tests were conducted to confirm the performance of our process using bio-indicators called daphnia (Daphnia magna), which demonstrated the efficacy of the like-Fenton process after 4 h of degradation.


Assuntos
Tratamento Farmacológico da COVID-19 , Daphnia , Animais , Azitromicina/toxicidade , Cloro/toxicidade , Ecossistema , Redes Neurais de Computação , Água
4.
Chemosphere ; 291(Pt 2): 132696, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34718011

RESUMO

Increasing antimicrobial resistance has led to use of novel technologies such as nanomaterials and nanocomposites that have shown effective antimicrobial and/or antifungal activities against several gram-positive and gram-negative bacteria. There have been limited studies on antimicrobial properties of the combined polymer nanocomposites with transitional bimetallic nanoparticles such as nickel (Ni) and copper (Cu). Thus, the main objective of this study was to synthesis, characterize and investigate the antibacterial and antifungal properties of NiCu-PANI/PVA nanocomposite. The nanocomposite films with different amount of Ni and Cu salts were synthesized by chemical oxidative polymerization of polyaniline using HCl as oxidant and PVA as a stabilizer. Optical, chemical composition, and morphological characteristics as well as thermal stability were evaluated using UV-Visible, FTIR, SEM-EDX, and TGA analyses. Antimicrobial properties were then determined using the disc diffusion assay against gram-negative bacteria (i.e., Escherichia coli ATCC 25922, Klebsiella pneumonia ATCC 700603, Proteus sp.,) and gram-positive bacteria (i.e., Staphylococcus aureus ATCC 2593). Fungal plant pathogens including Aspergillus niger and Fusarium oxysporum f. sp. pisi were also evaluated for determination of antifungal activity of NiCu-PANI/PVA films. Among the synthesized films, Ni65Cu35-PANI/PVA showed excellent antibacterial activity against all the bacteria strains examined in this study. The diameters of inhibition zones for Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603, Proteus sp., and Staphylococcus aureus ATCC 2593 were 23, 23, 17, and 18 mm, respectively indicating good antibacterial activities. Additionally, NiCu-PANI/PVA, particularly the films with higher Cu intake, showed better antifungal activity against Fusarium oxysporum f. sp. pisi. However, NiCu-PANI/PVA was ineffective against Aspergillus niger.


Assuntos
Anti-Infecciosos , Nanocompostos , Compostos de Anilina , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Testes de Sensibilidade Microbiana , Estresse Oxidativo , Polimerização
5.
J Hazard Mater ; 423(Pt A): 126986, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34461534

RESUMO

Conductive crystalline polypyrrole (Cryst-PPy), Nickel-polypyrrole (Ni-PPy), and copper- polypyrole (Cu-PPy) hybrid materials were prepared using a chemical polymerization method in an aqueous solution. Part I was focused on the Chemical synthesis of Cryst-PPy powder from an organic medium. Cryst-PPy powder was successfully synthesized by chemical route from an organic medium of acetonitrile with polyethylene oxide as a stabilizing agent and oxidizing agent like potassium peroxydisulfate. The morphological study was showed the presence of spherical nanoparticles and cubic microparticles giving rise to a denser structure of PPy. In the second part, the based electrodes composites were examined in the oxidation of phenol by an electrochemical process in an alkaline medium. To follow the yield of phenol degradation at the alkaline solution, UV-visible analysis was performed at the following operating conditions: current density of 0.58 mA cm-2, phenol initial concentration of 0.150 M and for 3 h processing; the rate of phenol elimination was 56%, 38% and 28% for Cu-PPy, Ni-PPy, and pure PPy electrodes respectively. Thus, can be found that the doped Cu-PPy electrodes electrode is a new material with high electrochemical oxidation ability for phenol degradation in aqueous solutions.

6.
J Hazard Mater ; 421: 126719, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34364215

RESUMO

The photocatalytic degradation of pharmaceutical micropollutants of Penicillin G (PG) was investigated in a photoreactor at a laboratory scale. The impact of type of catalyst, pH, and initial concentration of PG were studied. Maximum removal efficiency was obtained at pH = 6.8, [ZnO]0 = 0.8 g L-1, and [PG]0 = 5 mg L-1 and reaction time of 150 min. The addition of persulfate sodium (PPS) enhanced the efficiency of the photocatalytic reaction. The efficiency of photolysis process in the presence of PPS was significantly improved to 72.72% compared to the classical photocatalysis system (56.71%). Optimum concentration of PPS to completely degraded PG was found to be 500 mg L-1. The QuEChERS extraction, GC-MS/MS method, and concentration technique showed favorable performance identification of the possible mechanism of PG degradation pathway. Toxicity of PG and its by-products were evaluated using microbioassays assessment based on nine selected bacterial strains. Results confirmed the effectiveness of the implemented system and its safe use via the bacteria Bacillus subtilis, which has illustrated significant activity. Due to the high efficiency, facility benefits, and low-cost of the suggested process, the process can be considered for the degradation of various pharmaceutical contaminants in pharmaceutical industry treatment under the optimal conditions.


Assuntos
Espectrometria de Massas em Tandem , Poluentes Químicos da Água , Catálise , Cinética , Penicilina G , Fotólise
7.
Food Chem Toxicol ; 151: 112099, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33677039

RESUMO

This article was focused on the elaboration of NiFe-Polyaniline glucose sensors via electrochemical technique. Firstly, the PANi (polyaniline) fibers were synthesized by oxidation of the monomer aniline on FTO (fluorine tin oxide) substrate. Secondly, the Nickel-Iron nanoparticles (NiFe (NPs)) were obtained by the Chronoamperometry method on the Polyaniline surface. The NiFe-PANi hybrid electrode was characterized by scanning electron microscopy (SEM), force atomic microscopy (AFM), Fourier-transformed infrared (FTIR), and X-ray diffraction (XRD). The electrochemical glucose sensing performance of the NiFe alloy nanoparticle was studied by cyclic voltammetry and amperometry. The fabricated glucose sensor Ni-Fe hybrid material exhibited many remarkable sensing performances, such as low-response time (4 s), sensitivity (1050 µA mM-1 cm-2), broad linear range (from 10 µM -1 mM), and low limit of detection (LOD) (0.5 µM, S/N = 3). The selectivity, reliability, and stability of the NiFe hybrid material for glucose oxidation were also investigated. All the results demonstrated that the NiFe-PANi/FTO hybrid electrode is very promising for application in electrochemical glucose sensing.


Assuntos
Compostos de Anilina/química , Técnicas Biossensoriais/instrumentação , Glucose/análise , Ferro/química , Nanopartículas Metálicas/química , Níquel/química , Técnicas Eletroquímicas/métodos , Limite de Detecção , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Epigenomics ; 8(11): 1459-1479, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27762633

RESUMO

AIM: The Developmental Origin of Health and Disease refers to the concept that early exposure to toxicants or nutritional imbalances during perinatal life induces changes that enhance the risk of developing noncommunicable diseases in adulthood. Patients/materials & methods: An experimental model with an adult chronic germ cell death phenotype resulting from exposure to a xenoestrogen was used. RESULTS: A reciprocal negative feedback loop involving decreased EZH2 protein level and increased miR-101 expression was identified. In vitro and in vivo knockdown of EZH2 induced an apoptotic process in germ cells through increased levels of apoptotic factors (BIM and BAD) and DNA repair alteration via topoisomerase 2B deregulation. The increased miR-101 levels were observed in the animal blood, meaning that miR-101 may be a part of a circulating mark of germ cell death. CONCLUSION: miR-101-EZH2 pathway deregulation could represent a novel pathophysiological epigenetic basis for adult germ cell disease with environmental and developmental origins.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Células Germinativas/metabolismo , MicroRNAs/metabolismo , Animais , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Morte Celular , Dano ao DNA , Epigênese Genética , Estradiol/análogos & derivados , Estradiol/farmacologia , Infertilidade Masculina/genética , Masculino , Ratos , Testículo/efeitos dos fármacos , Testículo/patologia
9.
Mutat Res Genet Toxicol Environ Mutagen ; 764-765: 46-57, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24486656

RESUMO

MiRNAs (microRNAs) are single-stranded non-coding RNAs of approximately 21-23 nucleotides in length whose main function is to inhibit gene expression by interfering with mRNA processes. MicroRNAs suppress gene expression by affecting mRNA (messenger RNAs) stability, targeting the mRNA for degradation, or both. In this review, we have examined how microRNA expression could be altered following exposure to chemicals and how they could represent appropriate tissue and more interestingly circulating biomarkers. Among the key questions before using the microRNA for evaluation of risk toxicity, it remains still to clarify how they could be causally involved in the adverse effects and how stable their changes are.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Xenobióticos/toxicidade , Animais , Biomarcadores , Expressão Gênica , Humanos , MicroRNAs/sangue , RNA Mensageiro/genética , Medição de Risco
10.
Toxicology ; 310: 29-38, 2013 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-23707492

RESUMO

Mycotoxin zearalenone (ZEN) is a cereal contaminant produced by various species of Fusarium fungi. When interacting with estrogen receptors, ZEN leads to animal fertility disturbances and other reproductive pathologies. Few data are available on the effects of perinatal exposure to ZEN, particularly in the blood-testis barrier. The aim of this study was to assess the impact of ZEN in adult rats exposed neonatally. We focused on the expression and cellular localization of major ABC transporters expressed in adult rat testis, comparing ZEN effects with those of Estradiol Benzoate (EB) neonatal exposure. Dose-dependent and long term modulations of mRNA and protein levels of Abcb1, Abcc1, Abcg2, Abcc4 and Abcc5 were observed, along with Abcc4 protein cellular delocalization. ZEN exposure of SerW3 Sertoli cells showed modulation of Abcb1, Abcc4 and Abcc5. Comparison with EB exposure showed similar modulation profiles for Abcg2 but differential modulations for Abcb1, Abcc1, Abcc4 and Abcc5 in vivo, and a similar profile for Abcb1 modulation by ZEN and EB, but differential modulation for Abcc4 and Abcc5 in vitro. ZEN and EB effects were inhibited by in vitro addition of the pure anti-estrogen ICI 182.780, suggesting the at least partial implication of ZEN estrogenic activity in these modulations. These results suggested that ZEN neonatal exposure could affect the exposure of testis to ABC transporter substrates, and negatively influence spermatogenesis and male fertility.


Assuntos
Transportadores de Cassetes de Ligação de ATP/biossíntese , Estrogênios não Esteroides/toxicidade , Testículo/efeitos dos fármacos , Zearalenona/toxicidade , Envelhecimento/efeitos dos fármacos , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos , Western Blotting , Técnicas de Cultura de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Feminino , Fulvestranto , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Testículo/metabolismo
11.
Endocrinology ; 153(4): 1936-47, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22334722

RESUMO

Different studies have pointed out that developmental exposure to environmental endocrine disruptors can induce long-term testicular germ cell death probably through epigenetic mechanisms. By using a model of early neonatal post-natal day (PND) 1 to 5 exposure of male rats to a xenoestrogen, estradiol benzoate (EB), we investigated the role of microRNA and DNA methyltransferases (DNMT) on the developmental effects of EB on the adult germ cell death process. Neonatal exposure to EB induced adult germ cell apoptosis together with a dose-dependent increase in miR-29a, miR-29b, and miR-29c expression. Increased miR-29 expression resulted in a decrease in DNMT1, DNMT3a, and DNMT3b and antiapoptotic myeloid cell leukemia sequence 1 (Mcl-1) protein levels as shown in 1) germ cells of adult rats exposed neonatally to EB and 2) in spermatogonial GC-1 transfected with miR-29. The DNMT decrease was associated with a concomitant increase in transcript levels of DNA methylation target genes, such as L1td1-1 ORF1 and ORF2, Cdkn2a, and Gstp1, in correlation with their pattern of methylation. Finally, GC-1 cell lines transfection with miR-29a, miR-29b, or miR-29c undergo apoptosis evidenced by Annexin-V expression. Together, the increased miR-29 with a subsequent reduction in DNMT and Mcl-1 protein levels may represent a basis of explanation for the adult expression of the germ cell apoptosis phenotype. These observations suggest that the increased expression of the "apoptomir" miR-29 family represents the upstream mechanism identified until now that is involved in adult germ cell apoptosis induced by a neonatal hormonal disruption.


Assuntos
Regulação para Baixo/fisiologia , Estradiol/análogos & derivados , Metiltransferases/metabolismo , MicroRNAs/fisiologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espermatócitos/efeitos dos fármacos , Espermatócitos/metabolismo , Animais , Anexina A5/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Estradiol/farmacologia , Feminino , Masculino , Modelos Animais , Proteína de Sequência 1 de Leucemia de Células Mieloides , Fenótipo , Gravidez , Ratos , Ratos Sprague-Dawley , Espermatócitos/patologia , DNA Metiltransferase 3B
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