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1.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891864

RESUMO

According to the World Health Organization (WHO), breast cancer (BC) is the deadliest and the most common type of cancer worldwide in women. Several factors associated with BC exert their effects by modulating the state of stress. They can induce genetic mutations or alterations in cell growth, encouraging neoplastic development and the production of reactive oxygen species (ROS). ROS are able to activate many signal transduction pathways, producing an inflammatory environment that leads to the suppression of programmed cell death and the promotion of tumor proliferation, angiogenesis, and metastasis; these effects promote the development and progression of malignant neoplasms. However, cells have both non-enzymatic and enzymatic antioxidant systems that protect them by neutralizing the harmful effects of ROS. In this sense, antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), thioredoxin reductase (TrxR), and peroxiredoxin (Prx) protect the body from diseases caused by oxidative damage. In this review, we will discuss mechanisms through which some enzymatic antioxidants inhibit or promote carcinogenesis, as well as the new therapeutic proposals developed to complement traditional treatments.


Assuntos
Antioxidantes , Neoplasias da Mama , Espécies Reativas de Oxigênio , Humanos , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Peroxirredoxinas/metabolismo , Animais , Glutationa Peroxidase/metabolismo , Catalase/metabolismo , Superóxido Dismutase/metabolismo
2.
J Chem Phys ; 160(20)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38818896

RESUMO

Perovskite solar cells have demonstrated exceptional development over the past decade, but their stability remains a challenge toward the application of this technology. Several strategies have been used to address this, and the use of host-guest complexation has recently attracted more interest. However, this approach has primarily been exploited in conventional perovskite solar cells based on n-i-p architectures, while its use in inverted p-i-n devices remains unexplored. Herein, we employ representative crown ether, dibenzo-24-crown-8, for interfacial host-guest complexation in inverted perovskite solar cells based on methylammonium and methylammonium-free formamidinium-cesium halide perovskite compositions. Upon post-treatment of the perovskite films, we observed nanostructures on the surface that were associated with the reduced amount of trap states at the interface with the electron transport layer. As a result, we demonstrate improved efficiencies and operational stabilities following ISOS-D-2I and ISOS-L-2I protocols, demonstrating the viability of this approach to advance device stability.

3.
Plants (Basel) ; 13(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38475490

RESUMO

In the pursuit of identifying the novel resin glycoside modulators glucose-6-phosphatase and α-glucosidase enzymes, associated with blood sugar regulation, methanol-soluble extracts from the flowers of Ipomoea murucoides (cazahuate, Nahuatl), renowned for its abundance of glycolipids, were employed. The methanol-soluble extracts were fractionated by applying the affinity-directed method with glucose-6-phosphatase enzymes from a rat's liver and α-glucosidase enzymes from its intestines. Mass spectrometry and nuclear magnetic resonance were employed to identify the high-affinity compound as a free ligand following the release from the enzymatic complex. Gel permeation through a spin size-exclusion column allowed the separated high-affinity molecules to bind to glucose-6-phosphatase and α-glucosidase enzymes in solution, which led to the identification of some previously reported resin glycosides in the flowers of cazahuate, where a glycolipid mainly structurally related to murucoidin XIV was observed. In vitro studies demonstrated the modulating properties of resin glycosides on the glucose-6-phosphatase enzyme. Dynamic light scattering revealed conformational variations induced by resin glycosides on α-glucosidase enzyme, causing them to become more compact, akin to observations with the positive control, acarbose. These findings suggest that resin glycosides may serve as a potential source for phytotherapeutic agents with antihyperglycemic properties.

4.
Rev Invest Clin ; 76(1): 37-44, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38442374

RESUMO

Background: Osteoarthritis is a frequent rheumatic disease. Some single-nucleotide polymorphisms of the gene associated with fat mass and obesity are associated with increased body mass index and knee osteoarthritis. Objective: The objective of this study was to analyze the association of single nucleotide polymorphism rs1477196 of the fat mass and obesity gene with primary knee osteoarthritis. Methods: This observational and cross-sectional study included 347 Mexican participants. We performed the genotypification analysis with TaqMan® probe C_2031262_10 for rs1477196 (Thermo Fisher Scientific). Multivariate analysis included covariables such as age, type 2 diabetes, obesity, and postmenopause. Results: Type 2 diabetes, obesity, and postmenopause were associated with primary knee osteoarthritis in female participants. We did not find an association between rs1477196 and obesity. In the codominant and dominant genetic models, rs1477196 was significantly associated with primary knee osteoarthritis only in the female group, including in the model adjusted by other covariables (odds ratio = 2.517; 1.035-6.123; p = 0.042 and odds ratio = 2.387; 1.054-5.407; p = 0.037, respectively). The interaction between rs1477196 and obesity was significantly associated with primary knee osteoarthritis in female participants (p = 0.039 and p = 0.043). Conclusions: Our findings suggest that the rs1477196 variant of the fat and obesity mass gene may be associated with the risk of primary knee osteoarthritis in women.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato , Diabetes Mellitus Tipo 2 , Osteoartrite do Joelho , Feminino , Humanos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Estudos Transversais , México , Obesidade/epidemiologia , Obesidade/genética , Osteoartrite do Joelho/epidemiologia , Osteoartrite do Joelho/genética , Polimorfismo de Nucleotídeo Único
5.
Perinatol. reprod. hum ; 38(1): 7-11, ene.-mar. 2024. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1569377

RESUMO

Resumen Antecedentes: El incremento seminal de especies reactivas de oxígeno (ERO) se ha vinculado con la oxidación del ADN y anormalidades en la morfología espermática. La enzima 8-oxoguanina ADN glucosilasa 1 (OGG1) repara la oxidación del ADN. Sin embargo, la presencia del polimorfismo en la OGG1 que involucra cambio de citocina (C) por guanina (G), resultando la sustitución de una cisteína por una serina en el codón 326 (Ser326Cis), ha demostrado disminución en la reparación del ADN oxidado. Estudios del polimorfismo Ser326Cis en hombres españoles y asiáticos con infertilidad demostraron que el alelo G(Cis) incrementa las ERO, impactando en la infertilidad y en la teratozoospermia. Objetivo: Conocer la prevalencia del polimorfismo Ser326Cis de OGG1 en pacientes con teratozoospermia. Método: Se analizaron parámetros espermáticos y el polimorfismo Ser326Cis de OGG1 de 81 muestras de semen con teratozoospermia. Resultados: Los genotipos detectados fueron Ser326Ser(CC) 43%, Ser326Cis(CG) 41% y Cis326Cis(GG) 16%. La frecuencia del alelo G(Cis) fue de 0.4, valor mayor a la frecuencia reportada en las bases de datos disponibles para poblaciones americanas (0.21-0.29), los parámetros espermáticos no se relacionaron con el polimorfismo Ser326Cis. Conclusión: El alelo G(Cis) es un factor que contribuye a la infertilidad.


Abstract Background: The increase in seminal reactive oxygen species (ROS) has been linked to DNA oxidation and abnormalities in sperm morphology. The enzyme 8-oxoguanine DNA glycosylase 1 (OGG1) repairs DNA oxidation. However, the presence of the polymorphism in OGG1 that involves a change of cytokine (C) to guanine (G) resulting in the substitution of a cystine for serine at codon 326 (Ser326Cys) has shown a decrease in the repair of oxidized DNA. Studies of the Ser326Cys polymorphism in Spanish and Asian men with infertility demonstrated that the G(Cys) allele increases ROS, impacting infertility and teratozoospermia. Objective: To know the prevalence of the Ser326Cys polymorphism of OGG1 in patients with teratozoospermia. Method: Sperm parameters and the Ser326Cys polymorphism of OGG1 were analyzed from 81 semen samples. Results: The genotypes detected were Ser326Ser(CC) 43%, Ser326Cys(CG) 41%, and yis326Cys(GG) 16%. The frequency of the G allele (Cys) was 0.4, a value higher than the frequency reported in the databases available for American populations (0.21-0.29), the sperm parameters were not related to the Ser326Cys polymorphism. Conclusion: The G (Cys) allele is a factor that contributes to infertility.

6.
Rev. invest. clín ; 76(1): 37-44, Jan.-Feb. 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1560127

RESUMO

ABSTRACT Background: Osteoarthritis is a frequent rheumatic disease. Some single-nucleotide polymorphisms of the gene associated with fat mass and obesity are associated with increased body mass index and knee osteoarthritis. Objective: The objective of this study was to analyze the association of single nucleotide polymorphism rs1477196 of the fat mass and obesity gene with primary knee osteoarthritis. Methods: This observational and cross-sectional study included 347 Mexican participants. We performed the genotypification analysis with TaqMan® probe C_2031262_10 for rs1477196 (Thermo Fisher Scientific). Multivariate analysis included covariables such as age, type 2 diabetes, obesity, and postmenopause. Results: Type 2 diabetes, obesity, and postmenopause were associated with primary knee osteoarthritis in female participants. We did not find an association between rs1477196 and obesity. In the codominant and dominant genetic models, rs1477196 was significantly associated with primary knee osteoarthritis only in the female group, including in the model adjusted by other covariables (odds ratio = 2.517; 1.035-6.123; p = 0.042 and odds ratio = 2.387; 1.054-5.407; p = 0.037, respectively). The interaction between rs1477196 and obesity was significantly associated with primary knee osteoarthritis in female participants (p = 0.039 and p = 0.043). Conclusions: Our findings suggest that the rs1477196 variant of the fat and obesity mass gene may be associated with the risk of primary knee osteoarthritis in women.

7.
ACS Appl Mater Interfaces ; 15(48): 56547-56555, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38006332

RESUMO

In the quest for more efficient and cost-effective electrocatalytic systems, careful selection of catalysts and substrates plays a pivotal role. This study introduces an approach by synthesizing and depositing NiFe-layered double hydroxide (NiFe-LDH) catalysts on commercial AISI 304 substrates by using a low-temperature spray-coating technique. Through systematic investigations, the influence of processing conditions, such as the synthesis, ultrasonic power for having a stable nanoparticle's dispersion, and spray cycle optimization on the electrochemical and morphological properties of the coatings, is thoroughly explored. The results showcase exceptional catalytic performance, achieving an overpotential of 230 mV at 10 mA/cm2, with enhanced stability even at high current densities of 500 mA/cm2. The study highlights the significance of meticulous processing optimization and presents a scalable methodology that holds great potential for developing catalysts for oxygen evolution reactions (OER) and facilitates their integration into industrial processes.

8.
Antioxidants (Basel) ; 12(4)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37107209

RESUMO

Reduced glutathione (GSH) is the most abundant non-protein endogenous thiol. It is a ubiquitous molecule produced in most organs, but its synthesis is predominantly in the liver, the tissue in charge of storing and distributing it. GSH is involved in the detoxification of free radicals, peroxides and xenobiotics (drugs, pollutants, carcinogens, etc.), protects biological membranes from lipid peroxidation, and is an important regulator of cell homeostasis, since it participates in signaling redox, regulation of the synthesis and degradation of proteins (S-glutathionylation), signal transduction, various apoptotic processes, gene expression, cell proliferation, DNA and RNA synthesis, etc. GSH transport is a vital step in cellular homeostasis supported by the liver through providing extrahepatic organs (such as the kidney, lung, intestine, and brain, among others) with the said antioxidant. The wide range of functions within the cell in which glutathione is involved shows that glutathione's role in cellular homeostasis goes beyond being a simple antioxidant agent; therefore, the importance of this tripeptide needs to be reassessed from a broader metabolic perspective.

9.
Salud ment ; 45(6): 293-301, Nov.-Dec. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1432206

RESUMO

Abstract Introduction Among the Peruvian population, the prevalence of overweight and obesity has increased, making it one of the main public health problems. There is also conflicting evidence on the association between increased BMI and depressive symptoms in the adult population. Objective To determine the association between nutritional status (NS) and depressive symptoms (DS) in the Peruvian population. Method We conducted a secondary data analysis of the Peruvian Demographic and Family Health Survey (ENDES). We assessed the NS according to body mass index (BMI), grouped into normal weight (BMI = 18.50 - 24.99), overweight (BMI = 25.00 - 29.99), 1A obesity (BMI = 30.00 - 32.49), and 1B obesity (BMI ≥ 32.50). DS were assessed using the Patient Health Questionnaire (PHQ-9) instrument. A generalized linear model stratified by sex was constructed to calculate crude (cPRc) and adjusted (aPR) prevalence ratios. Results A total of 26,463 records of people aged 18-60 years were assessed, yielding a 6.3% prevalence of DS (≥ 10 points). Females had a higher frequency of DS than males, which increased depending on their NS: normal weight 7.8%, overweight 8.2%, 1A obesity 9.0%, and 1B obesity 12.0%. Likewise, in the multivariate analysis, women with 1B obesity reported a higher frequency of DS (aPR = 1.30; 95% CI = [1.03, 1.63]). Discussion and conclusion There is a strong association between nutritional status and depressive symptoms in Peruvian women, with obese women being more likely to have depressive symptoms.


Resumen Introducción Actualmente se ha incrementado la prevalencia de sobrepeso y obesidad en la población peruana, lo que la ha convertido en uno de los principales problemas de salud pública. Asimismo, existe evidencia contradictoria sobre la asociación entre el aumento del IMC y los síntomas depresivos en la población adulta. Objetivo Determinar la asociación entre el estado nutricional (EN) y los síntomas depresivos (SD) en la población peruana. Método Realizamos un análisis secundario de datos de la Encuesta Demográfica de Salud Familiar del Perú (ENDES). Se evaluó el EN según el índice de masa corporal (IMC), agrupándose en normopeso (IMC = 18.50 - 24.99), sobrepeso (IMC = 25.00 - 29.99), obesidad 1A (IMC = 30.0 - 32.49) y obesidad 1B (IMC ≥ 32.50). Los SD se evaluaron mediante el instrumento Patient Health Questionnaire (PHQ-9). Se construyó un modelo lineal generalizado estratificado por sexo para el cálculo de razones de prevalencias crudas (RPc) y ajustadas (RPa). Resultados Se evaluó un total de 26,463 registros de personas de entre 18 y 60 años. La prevalencia de SD (≥ 10 puntos) fue 6.3%. Las mujeres presentaron una mayor frecuencia de SD que los varones, la cual se incrementó con el EN, siendo: normopeso 7.8%, sobrepeso 8.2%, obesidad 1A 9.0% y obesidad 1B 12.0%. Asimismo, en el análisis multivariado, las mujeres con obesidad 1B reportaron una mayor frecuencia de SD (RPa = 1.30; IC 95% = [1.03, 1.63]). Discusión y conclusión Existe una gran asociación entre el estado nutricional y los síntomas depresivos en mujeres peruanas. Así, se llega a la conclusión de que las mujeres obesas tienen mayor probabilidad de presentar síntomas depresivos.

10.
Plants (Basel) ; 11(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36432893

RESUMO

Phytochemical screening of an ethanol-water extract (EWE) from the bark of Croton guatemalensis led to the isolation and identification of eight compounds, among them: five ent-clerodane diterpenoids [junceic acid (1), 6(s)-acetoxy-15,16-diepoxy-ent-cleroda-3,13(16),14-trien-20-oic acid (crotoguatenoic acid A) (2), 6(s)-hydroxyoxy-15,16-diepoxy-ent-cleroda-3,13(16),14-trien-20-oic acid (crotoguatenoic acid B) (3), formosin F (4), bartsiifolic acid (5)], and three flavonoids [rutin (6), epicatechin (7), and quercetin (8)]. Of these, 2 and 3 are reported here for the first time. Structures were established through conventional spectroscopy methods and their absolute configurations were determined by optical rotation and comparison of experimental electronic circular dichroism (ECD) and theoretical calculated ECD spectra. A suitable high performance liquid chromatography (HPLC) method for quantifying rutin (6) was developed and validated according to standard protocols. Affinity-directed fractionation was used to identify possible in vitro active compounds on α-glucosidases from Saccharomyces cerevisiae. HPLC-ESI-MS was used to identify the inhibitors as free ligands after being released from the enzymatic complex by denaturing acidic conditions. The affinity studies led to the identification of ent-clerodane diterpenoids as active compounds. In silico analysis allowed us to determine the best conformational rearrangement for the α-glucosidase inhibitors.

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