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1.
Curr Nutr Rep ; 12(1): 141-150, 2023 03.
Article in English | MEDLINE | ID: mdl-36692807

ABSTRACT

PURPOSE OF REVIEW: Oxidative stress is related to the pathogenesis of several chronic diseases, including inflammatory processes. Free radicals excess increase not only oxidative stress but also genomic instability. Polyphenols are non-enzymatic antioxidants that act as a defense barrier against free radicals and non-radical oxidants. The purpose of this article was to review published articles relating dietary polyphenols contained in grape seed proanthocyanidin extracts with its potential for reversing DNA damage. RECENT FINDINGS: Proanthocyanidin components exert pleiotropic actions having several biological, biochemical, and significant pharmacological effects and showed the ability to reduce cytotoxicity and genotoxicity. Grape seed proanthocyanidin extracts showed the ability to reduce cytotoxicity and genotoxicity through the comet assay and the micronucleus technique.


Subject(s)
Grape Seed Extract , Neoplasms , Vitis , Humans , Grape Seed Extract/pharmacology , Free Radicals , DNA Damage , Neoplasms/prevention & control , Polyphenols/pharmacology , Inflammation
2.
ACS Appl Mater Interfaces ; 13(51): 61139-61153, 2021 Dec 29.
Article in English | MEDLINE | ID: mdl-34915700

ABSTRACT

Comprehensive electrochemical and operando Raman studies are performed to investigate the electrochemical stability window (ESW) of supercapacitors filled with normal (salt-in-water) and highly concentrated (water-in-salt, WiSE) electrolytes. Impedance and chronoamperometric experiments are employed and combined with cyclic voltammetry to correctly define the ESW for a WiSE-based device. The total absence of water-splitting resulted in phase angles close to -90° in the impedance data. It is verified that a 17 m NaClO4 electrolyte avoids the water-splitting up to 1.8 V. Furthermore, Raman studies under dynamic and static polarization conditions corroborate the existence of a solvent blocking interface (SBI), which inhibits the occurrence of water-splitting. Also, the reversible nature of the charge-storage process is assessed as a function of the applied voltage. At extreme polarization, the SBI structure is disrupted, thus allowing the occurrence of water-splitting and anionic (ClO4-) intercalation between the graphene sheets.

3.
Article in English | MEDLINE | ID: mdl-34200547

ABSTRACT

Pesticides have been considered as potential chemical mutagens; however, little is known about toxic and genotoxic effects during pesticide application in Zamora-Jacona, Michoacan State in Mexico. This study sought to determine DNA damage and cholinesterase activities inhibitions in 54 agricultural workers exposed to complex mixtures of pesticides vs. control group (26 individuals) using Comet assay in peripheral whole blood, micronucleus (MN) test in oral mucosa cells, Cytokinesis-blocked MN assay in lymphocytes (L-CBMNcyt) and measuring AChE and BChE activities in whole blood and plasma samples, respectively. Exposed subjects demonstrated significantly elevated levels of primary (Comet assay: tail intensity, tail length, tail moment, Olive tail moment) and permanent DNA damage (MN assay: in blood/buccal cells; frequencies of nuclear buds, binucleated cells, cells with condensed chromatin, karyorrhexis, pyknosis, and karyolysis). However, inhibition of cholinesterase activities (AChE and BChE) was not observed in the workers. Confounding factors including sex, age, BMI, working exposure period, protection level, smoking habit (cigarettes per day units), alcohol consumption (weekly), medication, were considered in the analysis. These combined techniques demonstrated usefulness in the health hazards risks pesticide exposure assessment and suggested the need for periodic monitoring together with the education and the training of occupational workers for the safe application of potentially harmful pesticides.


Subject(s)
Occupational Exposure , Pesticides , Cholinesterases , Comet Assay , Cytogenetic Analysis , DNA Damage , Humans , Lymphocytes , Mexico , Micronucleus Tests , Mouth Mucosa , Occupational Exposure/adverse effects , Occupational Exposure/analysis , Pesticides/toxicity
4.
Pharm Biol ; 55(1): 2005-2014, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28738722

ABSTRACT

CONTEXT: Indigofera suffruticosa Miller (Fabaceae) and I. truxillensis Kunth produce compounds, such as isatin (ISA) and indirubin (IRN), which possess antitumour properties. Their effects in mammalian cells are still not very well understood. OBJECTIVE: We evaluated the activities of ISA and/or IRN on cell viability and apoptosis in vitro, their genotoxic potentials in vitro and in vivo, and the IRN- and ISA-induced expression of ERCC1 or BAX genes. MATERIALS AND METHODS: HeLa and/or CHO-K1 cell lines were tested (3 or 24 h) in the MTT, Trypan blue exclusion, acridine orange/ethidium bromide, cytokinesis-blocked micronucleus (CBMN) and comet (36, 24 and 72 h) tests after treatment with IRN (0.1 to 200 µM) or ISA (0.5 to 50 µM). Gene expression was measured by RT-qPCR in HeLa cells. Swiss albino mice received IRN (3, 4 or 24 h) by gavage (50, 100 and 150 mg/kg determined from the LD50 - 1 g/kg b.w.) and submitted to comet assay in vivo. RESULTS: IRN reduced the viability of CHO-K1 (24 h; 5 to 200 µM) and HeLa cells (10 to 200 µM), and was antiproliferative in the CBMN test (CHO-K1: 0.5 to 10 µM; HeLa: 5 and 10 µM). The drug did not induce apoptosis, micronucleus neither altered gene expression. IRN and ISA were genotoxic for HeLa cells (3 and 24 h) at all doses tested. IRN (100 and 150 mg/kg) also induced genotoxicity in vivo (4 h). CONCLUSION: IRN and ISA have properties that make them candidates as chemotherapeutics for further pharmacological investigations.


Subject(s)
DNA Damage/physiology , DNA-Binding Proteins/biosynthesis , Endonucleases/biosynthesis , Isatin/pharmacology , Mutagenesis/physiology , bcl-2-Associated X Protein/biosynthesis , Animals , Antibiotics, Antineoplastic/isolation & purification , Antibiotics, Antineoplastic/pharmacology , CHO Cells , Cell Survival/drug effects , Cell Survival/physiology , Cricetinae , Cricetulus , DNA Damage/drug effects , DNA-Binding Proteins/genetics , Dose-Response Relationship, Drug , Endonucleases/genetics , Female , Gene Expression , HeLa Cells , Humans , Indoles/isolation & purification , Indoles/pharmacology , Isatin/isolation & purification , Male , Mice , Mutagenesis/drug effects , Plant Components, Aerial , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , bcl-2-Associated X Protein/genetics
5.
Biota Neotrop. (Online, Ed. ingl.) ; 16(1): e20150028, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: biblio-951073

ABSTRACT

Studies of the genus Pinnularia Ehrenb. are only incipient in central-western Brazil, especially in Goiás. Only 20 of the 170 taxa known from Brazil were recorded in this state until now. A taxonomic study of Pinnularia from Lago dos Tigres (Tocantins-Araguaia River Basin) recorded 20 specific and infraspecific taxa, distributed in 17 species, including P. instabilis whose lectotype is designated here. Only P. meridiana var. meridiana was previously recorded in aquatic systems of the state. Eighteen taxa are newly recorded for Goiás, and one is the first record in Brazil. The Pinnularia flora from Lago dos Tigres contains nine taxa in common with the Amazon River Basin flora, and seven other taxa that occur elsewhere in the Paraná River Basin.


O gênero Pinnularia Ehrenb. é incipientemente estudado na região Centro-Oeste brasileira, especialmente em Goiás. Somente 20 de 170 táxons conhecidos no Brasil foram registrados nesse estado até agora. Nesse estudo, objetivou-se a realização de estudos taxonômicos de Pinnularia do Lago dos Tigres (Bacia Tocantins-Araguaia). Vinte táxons em nível específico e infraespecífico, distribuídos em 17 espécies, foram observados e caracterizados aqui, incluindo P. instabilis cujo lectótipo foi designado aqui. Somente P. meridiana var. meridiana foi primeiramente registrada em sistemas aquáticos do estado. Dezoito táxons constituíram citações pioneiras para o estado de Goiás e um foi o primeiro registro de ocorrência para o Brasil. A flora de Pinnularia do Lago dos Tigres apresentou nove táxons comuns com a Bacia Amazônica e outras sete foram comuns è Bacia do Paraná.

6.
Food Chem Toxicol ; 65: 233-41, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24394490

ABSTRACT

In vitro effects of flurochloridone (FLC) and its formulations Twin Pack Gold® [25% active ingredient (a.i.)] and Rainbow® (25% a.i.) were evaluated in HepG2 cells. Whereas cytokinesis-blocked micronucleus cytome (CBMN-cyt) and single-cell gel electrophoresis (SCGE) assays were employed for genotoxicity, MTT, neutral red, and apoptosis detections were used for cytotoxicity evaluation. Activities were tested within the concentration range of 0.25-15µg/ml FLC. Results demonstrated that neither FLC nor Rainbow® was able to induce MNs. On the other hand, 5µg/ml Twin Pack Gold® only increased MN frequency. Furthermore, 10 and 15µg/ml of both formulations resulted in cellular cytotoxicity demonstrated by alterations in the nuclear division index and cellular death. A marked increase in the genetic damage index was observed after treatment with all compounds. SCGE assay appeared to be more sensitive bioassay for detecting primary DNA strand breaks at lower concentrations of FLC than did MN. Our results reveal that FLC and its two formulations trigger apoptosis on HepG2 cells. The results represent the first experimental evidence of the in vitro apoptogenic role exerted on mammalian cells by FLC and the FLC-based formulations Rainbow® and Twin Pack Gold®, at least on HepG2 cells.


Subject(s)
Apoptosis/drug effects , DNA Damage , Herbicides/toxicity , Pyrrolidinones/toxicity , Comet Assay , Hep G2 Cells , Humans
7.
Article in English | MEDLINE | ID: mdl-24316526

ABSTRACT

Human serum albumin (HSA) is the most abundant protein in plasma. Cys34, the only free Cys residue, is the predominant plasma thiol and a relevant sacrificial antioxidant. Both in vivo circulating HSA and pharmaceutical preparations are heterogeneous with respect to the oxidation state of Cys34. In this work, we developed an external pH gradient chromatofocusing procedure that allows the analysis of the oxidation status of HSA in human plasma and biopharmaceutical products based on the different apparent isoelectric points and chemical properties of the redox isoforms. Specifically, reduced-mercury blocked HSA (HSA-SHg(+)), HSA with Cys34 oxidized to sulfenic acid (HSA-SOH) and HSA oxidized to sulfinate anion (HSA-SO2(-)) can be separated with resolutions of 1.4 and 3.1 (first and last pair) and hence quantified and purified. In addition, an N-terminally degraded isoform (HSA3-585) in different redox states can be resolved as well. Confirmation of the identity of the chromatofocusing isolated isoforms was achieved by high resolution whole protein MS. It is proposed that the chromatofocusing procedure can be used to produce more exact and complete descriptions of the redox status of HSA in vivo and in vitro. Finally, the scalability capabilities of the chromatofocusing procedure allow for the preparation of highly pure standards of several redox isoforms of HSA.


Subject(s)
Chromatography, High Pressure Liquid/methods , Serum Albumin/chemistry , Serum Albumin/isolation & purification , Aged , Humans , Hydrogen-Ion Concentration , Isoelectric Point , Male , Middle Aged , Protein Isoforms/analysis , Protein Isoforms/chemistry , Protein Isoforms/isolation & purification , Serum Albumin/analysis
8.
Food Chem Toxicol ; 62: 777-81, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24144947

ABSTRACT

The in vitro effects of S-metolachlor and its formulation Twin Pack Gold(®) (96% a.i.) were evaluated in human hepatoma (HepG2) cells. Cytokinesis-blocked micronucleus cytome (CBMN-cyt) and MTT assays as well as Neutral Red uptake were employed for genotoxicity and cytotoxicity evaluation. Activities were tested within the concentration range of 0.25-15 µg/ml S-metolachlor for 24h of exposure. Both compounds rendered a minor reduction in the NDI although not reaching statistical significance. Results demonstrated that the S-metolachlor was not able to induce MNs. On the other hand, 0.5-6 µg/ml Twin Pack Gold(®) increased the frequency of MNs. When cytotoxicity was estimated, S-metolachlor was not able to induce either a reduction of lysosomal or mitochondrial activity. Contrarily, whereas 1-15 µg/ml Twin Pack Gold(®) induced a significant reduction of mitochondrial activity, all tested concentrations of the formulated product induced a significant decrease of lysosomal performance as a function of the concentration of the S-metolachlor-based formulation titrated into cultures. Genotoxicity and cytotoxicity differences obtained with pure S-metolachlor and the commercial S-metolachlor-based formulation indicate that the latter may contain additional unsafe xenobiotics and support the concept of the importance of evaluating not only the active principle but also the commercial formulation when estimating the real hazard from agrochemicals.


Subject(s)
Acetamides/toxicity , Acetamides/administration & dosage , Dose-Response Relationship, Drug , Hep G2 Cells/drug effects , Humans , Lysosomes/drug effects , Micronucleus Tests , Mitochondria/drug effects , Toxicity Tests
9.
Rev. otorrinolaringol. cir. cabeza cuello ; 71(3): 197-202, dic. 2011. ilus, tab
Article in Spanish | LILACS | ID: lil-612120

ABSTRACT

Introducción: La obstrucción del lumen de las colleras es un evento infrecuente, pero que anula la efectividad del dispositivo en la ventilación del oído medio. Existen múltiples opciones de tratamiento tópico para esta situación clínica, sin embargo, los reportes en la literatura al respecto presentan resultados contradictorios. Objetivos: Analizar la efectividad de distintos tratamientos tópicos para destapar una collera ocluida con coágulo de sangre. Material y método: Modelo experimental ex vivo, 184 tubos de ventilación obstruidos con coágulo de sangre. Tratamiento tópico, 8 grupos experimentales (agua oxigenada 3 por ciento, ácido acético 5 por ciento, ciprofloxacino 0,3 por ciento, vinagre de mesa, heparina, mezcla de H2O2/acetato 1:1, suero fisiológico 0.9 por ciento) y 2 grupos control (sin tratamiento). Revisión de permeabilidad de lumen de colleras a los 3, 7 y 10 días. Resultados: El agua oxigenada (H2O2) resulta ser el tratamiento más efectivo (88 por ciento y 92 por ciento de efectividad a los 7 y 10 días). Ciprofloxacino, vinagre de mesa, suero fisiológico y heparina son inefectivos, sin diferencias significativas con grupo control. Ciprofloxacino y suero fisiológico sedimentan más, e incluso tapan colleras previamente permeables. Conclusiones: H2O2 es un tratamiento seguro, efectivo y económico para destapar colleras obstruidas con coágulos de sangre.


Introduction: Blocked tympanostomy tubes (TT) are an uncommon event, but avoids the effectiveness of this device in middle ear ventilation. Many topical treatment options are available for this clinical situation, however, reports in literature show conflicting results. Aim: Analyze the effectiveness of various topical treatments to open blood clot blocked TT. Material and Method: Ex vivo experimental model. 184 blood clot blocked TT. Topical treatment, 8 experimental groups (3 percent hydrogen peroxide, 5 percent acetic acid, 0,3 percent ciprofloxacin, vinegar, heparin, mixture 1:1 H2O2/acetate, 0.9 percent saline) and 2 control group (no treatment). Review of tube permeability at 3, 7 and 10 days of treatment. Results: H2O2 is the most effective treatment (88 percent & 92 percent effectiveness at 7 & 10 days). Ciprofloxacin, vinegar, saline and heparin are ineffective, with no statistical differences with control group. Ciprofloxacin and saline even blocked previously opened TT. Conclusions: H2O2 is a safe, effective and economic treatment to clear blood clot blocked TT.


Subject(s)
Humans , Anti-Infective Agents, Local/administration & dosage , Hydrogen Peroxide/administration & dosage , Thrombosis/drug therapy , Middle Ear Ventilation/adverse effects , Administration, Topical , Postoperative Complications , Prosthesis Failure , Models, Anatomic , Ear, Middle/surgery , Middle Ear Ventilation/instrumentation
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