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1.
Buenos Aires; IECS; 28 jul. 2020.
Non-conventional in Spanish | LILACS, BRISA | ID: biblio-1119361

ABSTRACT

CONTEXTO CLÍNICO: La enfermedad por el Coronavirus 2019 (COVID-19), por su sigla en inglés Coronavirus Disease 2019) es una enfermedad respiratoria de humanos por un nuevo Coronovirus identificado con la sigla SARS-CoV-2. TECNOLOGÍA: La vitamina C o ácido ascórbico es una vitamina soluble en agua con una función conocida sobre la síntesis de colágeno en tejidos conectivos y actúa como antioxidante. La vitamina D no solo es un nutriente sino también una hormona, que puede sintetizarse en nuestro cuerpo con la ayuda de la luz solar. El zinc es un oligoelemento dietético y es importante para el mantenimiento y el desarrollo de las células inmunes del sistema inmunitario innato y adaptativo. La deficiencia de Zinc resulta en la disfunción de la inmunidad humoral y mediada por células y aumenta la susceptibilidad a enfermedades infecciosas. OBJETIVO: El objetivo del presente informe es evaluar la evidencia disponible acerca de la eficacia, seguridad y aspectos relacionados a las políticas de cobertura del uso de suplementos vitamínicos (Vit. C, D) y Zinc en la infección por COVID-19. MÉTODOS: Se realizó una búsqueda en las principales bases de datos bibliográficas, en buscadores genéricos de internet, financiadores de salud. Se priorizó la inclusión de revisiones sistemáticas (RS), ensayos clínicos controlados aleatorizados (ECAs), evaluaciones de tecnologías sanitarias (ETS), evaluaciones económicas, guías de práctica clínica (GPC) y recomendaciones de diferentes organizaciones de salud. RESULTADOS: Se incluyeron una RS con MA, un protocolo de RS, un estudio observacional retrospectivo y ocho recomendaciones de sociedades científicas. No se hallaron estudios que evalúen la suplementación con vitaminas C y D para la prevención o tratamiento de la infección por COVID-19. Para Zinc, se halló un solo estudio que lo utiliza combinado con tratamientos discontinuados para esta patología por alertas en su seguridad. CONCLUSIONES: No hallaron estudios que evalúen la suplementación con las vitaminas C y D, solas o combinadas con otros tratamientos, en la prevención o tratamiento de la infección por COVID-19. Tampoco se encontraron estudios preventivos que evaluén el uso de Zinc. En el caso de su uso terapéutico, evidencia de muy baja calidad no permite determinar los efectos de la suplementación con Zinc en pacientes hospitalizados por COVID-19. Aunque se desconoce el efecto preventivo en relación al COVID-19, se halló evidencia de alta calidad de estudios realizados durante la era pre- COVID-19 que muestra que, en población general, la suplementación con vitamina D reduce el riesgo de infecciones respiratorias agudas. La incertidumbre actual podría reducirse a corto o mediano plazo debido a que se encuentran en curso aproximadamente 90 estudios que evaluarán el efecto de la administración C y D, y Zinc, solas o en combinación con otros tratamientos, para la prevención o tratamiento de la infección por COVID-19.


Subject(s)
Humans , Ascorbic Acid/administration & dosage , Vitamin D/administration & dosage , Zinc/administration & dosage , Coronavirus Infections/prevention & control , Betacoronavirus/drug effects , Technology Assessment, Biomedical , Health Evaluation , Cost-Benefit Analysis
3.
Int. j. morphol ; 38(1): 48-55, Feb. 2020. graf
Article in English | LILACS | ID: biblio-1056396

ABSTRACT

This research was designed to investigate the potential protective effect of vitamin C supplementation against hepatocyte ultrastructural alterations induced by artemether (antimalarial drug) administration. Twenty-four adult male albino rats were used in this study and were divided into four groups (n=6). Group I served as a control and rats in group II administrated artemether (4 mg/kg B.W) orally for three consecutive days. Group III administered artemether plus a low dose of vitamin C (2.86 mg/kg/l water) while group IV received artemether plusa high dose of vitamin C (8.56 mg/kg). At the end of the experimental period (14 days), the harvested liver tissues were examined by transmission electron microscopy (TEM), and blood samples were assayed for biomarkers of liver injury and oxidative stress. Artemether significantly (p<0.05) augmented biomarkers of liver injury such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and oxidative stress such as superoxide dismutase (SOD), Glutathione Peroxidase (GPX), and caused degeneration and damage of the rough endoplasmic reticulum and disrupted mitochondria. The blood sinusoids were also damaged with distortion of their canaliculi. Administration of vitamin C showed improvement of liver biomarkers, and liver parenchyma, especially in a high dose of vitamin C.We concludes that vitamin C is a partial protective agent against artemether-induced liver injury.


Esta investigación fue diseñada para investigar el posible efecto protector de la vitamina C contra las alteraciones ultraestructurales de los hepatocitos, inducidas por la administración de arteméter (medicamento antipalúdico). En el estudio se utilizaron 24 ratas albinas macho adultas y se dividieron en cuatro grupos (n = 6). El grupo I fue designado como control y las ratas en el grupo II se adminstró Arteméter (4 mg / kg de peso corporal) por vía oral durante tres días consecutivos. En el grupo III se administró arteméter, además de una dosis baja de vitamina C (2,86 mg / kg / l de agua) mientras que el grupo IV recibió arteméter más una dosis alta de vitamina C (8,56 mg / kg). Al final del período experimental (14 días), los tejidos hepáticos recolectados se examinaron por microscopía electrónica de transmisión (MET), y las muestras de sangre se analizaron en busca de biomarcadores de daño hepático y estrés oxidativo. El arteméter aumentó significativamente (p <0,05) los biomarcadores de daño hepático como alanina aminotransferasa (ALT), aspartato aminotransferasa (AST) y estrés oxidativo como superóxido dismutasa (SOD), glutatión peroxidasa (GPX) y causó degeneración y daño de la retículo endoplásmico rugoso y mitocondrias alteradas. Los sinusoides sanguíneos también fueron dañados con la distorsión de sus canalículos. La administración de vitamina C mostró una mejoría de los biomarcadores hepáticos y el parénquima hepático, especialmente en una dosis alta de vitamina C. Concluimos que la vitamina C es un agente protector parcial contra la lesión hepática inducida por arteméter.


Subject(s)
Animals , Rats , Ascorbic Acid/administration & dosage , Chemical and Drug Induced Liver Injury, Chronic/drug therapy , Artemether/toxicity , Ascorbic Acid/pharmacology , Superoxide Dismutase/analysis , Biomarkers , Rats, Sprague-Dawley , Oxidative Stress/drug effects , Hepatocytes/drug effects , Hepatocytes/ultrastructure , Microscopy, Electron, Transmission , Disease Models, Animal , Hepatoprotector Drugs , Chemical and Drug Induced Liver Injury/pathology , Glutathione Peroxidase/analysis
4.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 9-17, Jan.-Feb. 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1088933

ABSTRACT

The aim of this study was to evaluate the addition of vitamin C, reduced glutathione and the association thereof to the bovine semen cryopreservation extender. The ejaculate from nine bulls were divided into four fractions, each corresponding to a treatment, namely: control group-semen diluted with Tris-yolk extender; vitamin C group-semen diluted in Tris-yolk extender supplemented with vitamin C (2.5mmol/mL); glutathione group-semen diluted in Tris-yolk extender supplemented with reduced glutathione (2.5mmol/mL) and associated group-semen diluted in Tris-yolk extender supplemented with vitamin C (1.25mmol/mL) and reduced glutathione (1.25mmol/mL). Afterwards, the semen was packed into French straws and submitted to cryopreservation using automated equipment. After cryopreservation, the semen was thawed and evaluated considering sperm motility, morphology, plasma membrane, acrosome, mitochondrial potential and oxidative stress, as well as the thermo resistance test. Extender's supplementation with the association of vitamin C and reduced glutathione showed benefic effects on sperm motility and preservation of plasma and acrosomal membranes during semen cryopreservation, being also the group that showed higher values of reactive oxygen species. Thus, the association of both antioxidants contributed to the preservation of sperm cells in every analyzed characteristic, suggesting its use on bovine semen cryopreservation.(AU)


O objetivo deste estudo foi avaliar a adição de vitamina C, glutationa reduzida e sua associação ao diluidor de criopreservação de sêmen bovino. O ejaculado de nove touros foi dividido em quatro frações, cada uma correspondendo a um tratamento, a saber: grupo controle - sêmen diluído em Tris-gema; grupo vitamina C - sêmen diluído em Tris-gema, suplementado com vitamina C (2,5mmol/mL); grupo glutationa - sêmen diluído em Tris-gema, suplementado com glutationa reduzida (2,5mmol/mL) e grupo sêmen associado - diluído em Tris-gema, suplementado com vitamina C (1,25mmol/mL) e glutationa reduzida (1,25mmol/mL ). Posteriormente, o sêmen foi envasado em palhetas francesas e submetido à criopreservação por meio de equipamento automatizado. Após a criopreservação, o sêmen foi descongelado e avaliado quanto à motilidade espermática, à morfologia, à membrana plasmática, ao acrossoma, ao potencial mitocondrial e ao estresse oxidativo, bem como pelo teste de resistência térmica. A suplementação de extensor com a associação de vitamina C e glutationa reduzida mostrou efeitos benéficos sobre a motilidade espermática e a preservação das membranas plasmática e acrossomal durante a criopreservação de sêmen, sendo também o grupo que apresentou maiores valores de espécies reativas de oxigênio. Assim, a associação de ambos os antioxidantes contribuiu para a preservação dos espermatozóides em todas as características analisadas, sugerindo sua utilização na criopreservação de sêmen bovino.(AU)


Subject(s)
Animals , Male , Cattle , Ascorbic Acid/administration & dosage , Semen Preservation/veterinary , Reactive Oxygen Species , Oxidative Stress , Glutathione
5.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 145-152, Jan.-Feb. 2020. tab
Article in English | LILACS, VETINDEX | ID: biblio-1088907

ABSTRACT

This study aimed to evaluate the addition of Vitamin C, reduced Glutathione and trolox on sperm characteristics of pork refrigerated semen. Six pigs were collected through the technique of gloved hand (10 ejaculates/animals). The semen was diluted in MR-A®. After the previous evaluations, the treatments were added: Control group: diluent only; Vitamin C Group: 200µM/mL Vitamin C; Trolox Group: 200µM/mL Trolox; Glutathione group: 2.5mM/ml Reduced glutathione. The semen was stored in thermal boxes and placed inside the refrigerator at 15oC and evaluated at D0, 12, 48, 72 hours. After 30 hours of incubation, each treatment was divided into two equal fractions and the same concentration of antioxidants was added in one of the parts. The results show that reduced glutathione supplementation preserves sperm motility after 24 hours but also has a higher percentage of acrosome intact in the presence of this antioxidant. There was no effect of adding a second dose of the antioxidants. In conclusion, the addition of reduced Glutathione to the swine semen diluent is a promising alternative for better preservation of sperm characteristics and the addition of the second dose of antioxidants during storage is detrimental to semen.(AU)


Este estudo tem como objetivo avaliar a adição da vitamina C, da glutationa reduzida e do trolox sobre características espermáticas do sêmen refrigerado de suínos. Seis cachaços foram coletados pela técnica de mão enluvada (10 coletas/animal). O sêmen foi diluído em MR-A®. Após as avaliações prévias, os tratamentos foram adicionados: grupo controle: apenas diluidor; grupo vitamina C: 200µM/mL de vitamina C; grupo trolox: 200µM/mL de trolox; grupo glutationa: 2.5mM/mL de glutationa reduzida. O sêmen foi armazenado em caixas térmicas e alocado dentro do refrigerador a 15oC e avaliado nos tempos zero, 12, 48 e 72 horas . Após 30 horas de incubação, cada tratamento foi dividido em duas frações iguais e adicionou-se a mesma concentração de antioxidantes em uma das partes. Os resultados demonstram que a suplementação de glutationa reduzida preserva a motilidade espermática após 24 horas, bem como tem maior percentual de acrossoma intacto na presença desse antioxidante. Não houve efeito ao se adicionar uma segunda dose dos antioxidantes. Em conclusão, o acréscimo da glutationa reduzida ao diluidor de sêmen suíno é uma alternativa promissora para melhor preservação das características espermáticas, e a adição da segunda dose dos antioxidantes durante o armazenamento é prejudicial ao sêmen.(AU)


Subject(s)
Animals , Male , Ascorbic Acid/administration & dosage , Semen Preservation/methods , Spermatozoa , Swine , Glutathione/administration & dosage , Semen Preservation/veterinary , Antioxidants/analysis
6.
J. appl. oral sci ; 28: e20200444, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1143142

ABSTRACT

Abstract Objective: This study evaluated the effects of local vitamin C treatment on tissue advanced glycation end products (AGE), interleukin (IL)-6, 8-hydroxy-2-deoxyguanosine (8-OHdG), and matrix metalloproteinases (MMP)-8 in tissues; serum C-terminal telopeptide fragments (CTX); and alveolar bone loss (ABL) in rats. Methodology: 35 male Sprague Dawley rats were divided equally into five groups: 1) control (C), 2) experimental periodontitis (P), 3) experimental diabetes (D), 4) experimental diabetes and experimental periodontitis (D + P), and 5) experimental diabetes-experimental periodontitis-locally applied vitamin C (D + P + LvitC). Diabetes was induced in rats with alloxan monohydrate, after which periodontitis was induced by ligature placement in the right mandibular first molar teeth for 11 days. In the treatment group, vitamin C was administered locally three times with two-days interval after ligature removal. The animals were sacrificed, and the samples were analyzed histometrically and immunohistochemically. Results: CTX, 8-OHdG, and AGE values significantly decreased in the treatment group compared to the D + P group. IL-6 and MMP-8 values decreased in the treatment group compared to the D + P group, but this is not significant. ABL was significantly reduced by the local delivery of vitamin C. Conclusion: This study reveals that vitamin C treatment may be beneficial to reduce serum CTX and gingival MMP-8 levels, oxidative stress, inflammation, and AGE accumulation in periodontal tissue. Vitamin C may be an immunomodulator and antioxidant locally applied in the treatment of periodontitis to reduce the adverse effects of diabetes in periodontal tissues.


Subject(s)
Animals , Male , Rats , Periodontitis/drug therapy , Ascorbic Acid/administration & dosage , Alveolar Bone Loss , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/drug therapy , Peptides , Interleukin-6 , Rats, Sprague-Dawley , Glycation End Products, Advanced , Oxidative Stress , Matrix Metalloproteinase 8 , Collagen Type I
7.
Rev. chil. nutr ; 46(6): 800-808, dic. 2019. tab, graf
Article in Spanish | LILACS | ID: biblio-1058144

ABSTRACT

RESUMEN La vitamina C es uno de los antioxidantes más conocidos. Su ingesta ha sido asociada a un sinnúmero de beneficios, algunos de los cuales tienen un sustento científico débil o inexistente. En esta revisión se presentan en forma resumida aspectos biológicos que determinan la homeostasis de la vitamina C y se discute la información disponible sobre sus posibles efectos benéficos y su ingesta, en diversos países con especial énfasis en algunos grupos de riesgo. También se presentan sus efectos benéficos en inflamación, cáncer y enfermedades cardiovasculares, así como su acción de inmunomodulador y regulador epigenético. Se revisan también algunas fuentes dietarias de vitamina C y los factores que influyen en su estabilidad. Terminando con un análisis general de los trabajos relacionados con conducta de vida saludable en países latinoamericanos, que reflejan los malos hábitos alimentarios y que podrían dar cuenta de una hipovitaminosis de vitamina C aún no reportada y repercutir en el desarrollo de envejecimiento precoz y enfermedades crónicas no transmisibles.


ABSTRACT Vitamin C is a well-known antioxidant. Its intake has been associated with a number of benefits, some of which lack a scientific basis. This review summarizes important biological aspects that determine vitamin C homeostasis, discusses the available information on its possible beneficial effects and its intake in various countries, with special emphasis on some risk groups. The beneficial effects of this vitamin in inflammation, cancer and cardiovascular disease are also summarized, as well as its role as immuno-modulator and epigenetic regulator. Dietary sources of vitamin C and the factors that influence its stability are also presented. Finally, an overview of the research conducted on healthy lifestyles in Latin-American countries are presented. This research summarized provides evidence of poor eating habits, which could account for a vitamin C hypovitaminosis not yet reported that could be associated with unhealthy ageing and the development of non-transmissible chronic diseases.


Subject(s)
Humans , Ascorbic Acid/administration & dosage , Antioxidants/administration & dosage , Ascorbic Acid/chemistry , Homeostasis , Antioxidants/chemistry
8.
Rev. bras. cir. cardiovasc ; 34(5): 517-524, Sept.-Oct. 2019. tab
Article in English | LILACS | ID: biblio-1042055

ABSTRACT

Abstract Objective: To evaluate the effect of high-dose vitamin C on cardiac reperfusion injury and plasma levels of creatine kinase-muscle/brain (CK-MB), troponin I, and lactate dehydrogenase (LDH) in patients undergoing coronary artery bypass grafting (CABG). Methods: This is a double-blind randomized clinical trial study. Fifty patients (50-80 years old) who had CABG surgery were selected. The intervention group received 5 g of intravenous vitamin C before anesthesia induction and 5 g of vitamin C in cardioplegic solution. The control group received the same amount of placebo (normal saline). Arterial blood samples were taken to determine the serum levels of CK-MB, troponin I, and LDH enzymes. Left ventricular ejection fraction was measured and hemodynamic parameters were recorded at intervals. Results: High doses of vitamin C in the treatment group led to improvement of ventricular function (ejection fraction [EF]) and low Intensive Care Unit (ICU) stay. The cardiac enzymes level in the vitamin C group was lower than in the control group. These changes were not significant between the groups in different time intervals (anesthesia induction, end of bypass, 6 h after surgery, and 24 h after surgery) for CK-MB, LDH, and troponin I. Hemodynamic parameters, hematocrit, potassium, urinary output, blood transfusion, arrhythmia, and inotropic support showed no significant difference between the groups. Conclusion: Vitamin C has significantly improved the patients' ventricular function (EF) 72 h after surgery and reduced the length of ICU stay. No significant changes in cardiac biomarkers, including CK-MB, troponin I, and LDH, were seen over time in each group. IRCT code: IRCT2016053019470N33


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Aged, 80 and over , Ascorbic Acid/administration & dosage , Myocardial Reperfusion Injury/prevention & control , Coronary Artery Bypass/methods , Antioxidants/administration & dosage , Arrhythmias, Cardiac/prevention & control , Time Factors , Biomarkers/blood , Myocardial Reperfusion Injury/blood , Double-Blind Method , Reproducibility of Results , Ventricular Function/drug effects , Treatment Outcome , Statistics, Nonparametric , Troponin I/blood , Creatine Kinase, BB Form/blood , Creatine Kinase, MM Form/blood , Hemodynamics/drug effects , Intensive Care Units , L-Lactate Dehydrogenase/blood
9.
Braz. arch. biol. technol ; 62: e19180520, 2019. tab, graf
Article in English | LILACS | ID: biblio-1055388

ABSTRACT

Abstract An experiment was conducted to evaluate the performance of suckling piglets subjected to oral administration of citrus extracts (CE). Twenty sows were used with ten sucking piglets on average initial weight of 1.26 kg (± 0.32) for 21 days. The experimental design was a randomized complete block design with two treatments: Negative Control (without antimicrobials) and Citrus Extracts (ascorbic acid + flavonoids, oral administration of 0.3 mg kg of BW via pigdoser) with ten repetitions each. The number of live-born piglets in females PO5 was 21% higher than in PO3 sows. Sows where piglets received CE showed a 10% higher (P <0.05) feed intake in the last week of lactation. From 8 to 21 days, the feed conversion of NC sows was 23 and 38% lower (P <0.05) than sows where piglets received CE. Piglet mortality was 13.4% in NC group and 3.9% in CE group in a single dose on the third day of life. The villous length in the duodenum was 24% higher (P <0.01) in piglets receiving CE. The administration of CE increased 19% (P = 0.02) the villous length of the ileum region of suckling piglets. Frequency of normal feces was higher (P<0.05) in piglets CE group. Oral administration of CE containing flavonoids and ascorbic acid to suckling piglets not improves the piglet growth. However, it alters the gut morphology, and reduces the frequency of diarrhea during suckling period. Parity order interferes on feed intake, feed conversion of sows and performance of litters.


Subject(s)
Animals , Infant , Ascorbic Acid/administration & dosage , Swine , Flavonoids/administration & dosage , Gastrointestinal Microbiome/drug effects
10.
Braz. j. med. biol. res ; 52(9): e8290, 2019. graf
Article in English | LILACS | ID: biblio-1019570

ABSTRACT

Tendon rupture is a very frequent accident involving average people and high-performance athletes. Clinical studies describe tendon recovery as a painful and slow process involving different biochemical and histological events. Ascorbic acid (AA) is a potent antioxidant as well as an important cofactor for collagen synthesis. In the current study, we evaluated if local treatment with AA is able to promote tendon repair in tenotomized rats. Animals were submitted to Achilles tendon rupture followed by surgical suture. Control and AA groups received in loco injection of saline solution (0.9% NaCl) and 30 mM AA, respectively. Histological and functional recovery of Achilles tendon tissue was evaluated at 7, 14, and 21 days post-surgery. Hematoxylin/eosin staining and collagen fluorescence analysis showed intense disarrangement of tendon tissue in the saline group. Tenotomized animals also showed hypercellularity in tendon tissue compared with non-tenotomized animals. The Achilles functional index (AFI) showed a significant decrease of tendon functionality in tenotomized animals at 7, 14, and 21 days post-surgery. AA accelerated tissue organization and the recovery of function of the Achilles tendons. The beneficial effect of AA treatment was also observed in the organization of the collagen network. Data presented in the current work showed that in loco treatment with AA accelerated the recovery of injured Achilles tendon post-surgery.


Subject(s)
Animals , Male , Rats , Ascorbic Acid/administration & dosage , Achilles Tendon/drug effects , Tendon Injuries/surgery , Collagen/drug effects , Achilles Tendon/injuries , Achilles Tendon/pathology , Wound Healing/drug effects , Collagen/physiology , Rats, Wistar , Recovery of Function/drug effects , Disease Models, Animal , Tenotomy
11.
Medwave ; 18(4): e7236, 2018.
Article in English, Spanish | LILACS | ID: biblio-912336

ABSTRACT

INTRODUCCIÓN: El resfrío común es una enfermedad muy frecuente. Existe la creencia que el consumo de vitamina C previene su aparición, pero la real eficacia de esta medida es controvertida. MÉTODOS: Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, reanalizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES Identificamos ocho revisiones sistemáticas que en conjunto incluyen 45 estudios primarios, de los cuales 31 corresponden a ensayos aleatorizados. Concluimos que el consumo de vitamina C no previene la aparición del resfrío común.


INTRODUCTION: The common cold is one of the most common diseases. It is generally believed that the consumption of vitamin C prevents its appearance, but the actual efficacy of this measure is controversial. METHODS: To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified eight systematic reviews including 45 studies overall, of which 31 were randomized trials. We concluded the consumption of vitamin C does not prevent the incidence of common cold.


Subject(s)
Humans , Ascorbic Acid/administration & dosage , Common Cold/prevention & control , Antioxidants/administration & dosage , Randomized Controlled Trials as Topic , Databases, Factual , Treatment Outcome , Common Cold/epidemiology
12.
Braz. j. otorhinolaryngol. (Impr.) ; 83(5): 541-545, Sept.-Oct. 2017. tab, graf
Article in English | LILACS | ID: biblio-889311

ABSTRACT

Abstract Introduction: The ethiopathogenesis of tympanosclerosis has not been completely under- stood yet. Recent studies have shown that free oxygen radicals are important in the formation of tympanosclerosis. Melatonin and Vitamin C are known to be a powerful antioxidant, interacts directly with Reactive Oxygen Species and controls free radical-mediated tissue damage. Objective: To demonstrate the possible preventative effects of melatonin and Vitamin C on tympanosclerosis in rats by using histopathology and determination of total antioxidant status total antioxidant status. Methods: Standard myringotomy and standard injury were performed in the middle ear of 24 rats. The animals were divided into three groups: Group 1 received melatonin, Group 2 received vitamin C, and Group 3 received saline solution. Results: The mean values of total antioxidant status were similar in the all study groups before the treatment period. The mean values of total antioxidant status were significantly higher in the melatonin and vitamin C groups compared to control group but vitamin C with melatonin groups were similar after the treatment period (p < 0.001). Minimum and maximum wall thicknesses were lower in the melatonin and vitamin C groups compared to the control group but the differences were insignificant. Conclusion: Melatonin increases total antioxidant status level and might have some effect on tympanosclerosis that develops after myringotomy.


Resumo Introdução: A etiopatogênese da timpanoesclerose (TE) não foi ainda totalmente esclarecida. Estudos recentes têm demonstrado que os radicais livres de oxigênio são importantes na formação de TE. Melatonina e vitamina C são conhecidas por serem poderosos antioxidantes, interagir diretamente com espécies reativas de oxigênio (ROS) e controlar danos em tecidos mediados por radicais livres. Objetivo: Demonstrar os possíveis efeitos preventivos da melatonina e da vitamina C na TE em ratos com histopatologia e determinação da capacidade antioxidante total (CAT). Método: Miringotomias padronizadas foram feitas na orelha média de 24 ratos. Os animais foram divididos em três grupos: o Grupo 1 recebeu melatonina, o Grupo 2 vitamina C e o grupo 3 solução salina. Resultados: Os valores médios de CAT foram semelhantes em todos os grupos de estudo antes do período de tratamento. Os valores médios de CAT foram significativamente maiores nos grupos que receberam melatonina e vitamina C em comparação com o grupo de controle, mas os grupos vitamina C e melatonina foram semelhantes após o período de tratamento (p < 0,001). As espessuras mínimas e máximas de parede foram menores nos grupos melatonina e vitamina C, em comparação com o grupo controle, mas as diferenças não foram significativas. Conclusão: A melatonina aumenta os níveis de CAT e pode ter algum efeito sobre a TE que se desenvolve após a miringotomia.


Subject(s)
Animals , Male , Rats , Ascorbic Acid/administration & dosage , Vitamins/administration & dosage , Myringosclerosis/drug therapy , Melatonin/administration & dosage , Antioxidants/administration & dosage , Tympanic Membrane/drug effects , Rats, Wistar , Disease Models, Animal , Myringosclerosis/pathology
13.
Electron. j. biotechnol ; 25: 1-8, ene. 2017. graf, ilus
Article in English | LILACS | ID: biblio-1008175

ABSTRACT

Background: Ascorbic acid (Asc) is one of the most abundant antioxidants and it serves as a major contributor to protect plants against oxidative damage. Plants use two enzymes that participate in the metabolic recycling of Asc. One of these two enzymes is dehydroascorbate reductase (DHAR). It directly regenerates Asc from its oxidized state and thus prevents Asc from being irreversibly hydrolyzed to 2, 3-diketogulonic acid. This study aimed to examine whether over-expression of DHAR leads to an enhanced oxidative stress tolerance in tobacco plants. Results: In this study, we functionally characterized a novel JcDHAR gene from Jatropha curcas and found via quantitative RT-PCR analysis that JcDHAR can be induced with H2O2, salt and PEG stresses. The DHAR activities of transgenic tobacco plants increased from 2.0 to 5.3 fold compared to wild-type plants. As a result, the transgenic plants displayed enhanced tolerance to oxidative stress. Conclusions: Our results indicate that JcDHAR expression can effectively enhance the tolerance to oxidative stress in plants.


Subject(s)
Oxidoreductases/metabolism , Ascorbic Acid/administration & dosage , Tobacco/enzymology , Plants, Genetically Modified/enzymology , Antioxidants/administration & dosage , Oxidoreductases/isolation & purification , Oxidoreductases/genetics , Ascorbic Acid/metabolism , Stress, Physiological , Tobacco/drug effects , Blotting, Western , Plants, Genetically Modified/drug effects , Reactive Oxygen Species , Oxidative Stress , Reverse Transcriptase Polymerase Chain Reaction , Salt Tolerance , Antioxidants/metabolism
14.
Rev. bras. anestesiol ; 66(1): 29-36, Jan.-Feb. 2016. graf
Article in Portuguese | LILACS | ID: lil-773481

ABSTRACT

BACKGROUND: Intra-articular injections of local anesthetics are commonly used to enhance post-operative analgesia following orthopedic surgery as arthroscopic surgeries. Nevertheless, recent reports of severe complications due to the use of intra-articular local anesthetic have raised concerns. OBJECTIVES: The study aims to assess use of vitamin C in reducing adverse effects of the most commonly employed anesthetics - ropivacaine, bupivacaine and lidocaine - on human chondrocytes. METHODS: The chondrocyte viability following exposure to 0.5% bupivacaine or 0.75% ropivacaine or 1.0% lidocaine and/or vitamin C at doses 125, 250 and 500 µM was determined by LIVE/DEAD assay and annexin V staining. Expression levels of caspases 3 and 9 were assessed using antibodies by Western blotting. Flow cytometry was performed to analyze the generation of reactive oxygen species. RESULTS: On exposure to the local anesthetics, chondrotoxicity was found in the order ropivacaine < bupivacaine < lidocaine. Vitamin C effectively improved the reduced chondrocyte viability and decreased the raised apoptosis levels following exposure to anesthesia. At higher doses, vitamin C was found efficient in reducing the generation of reactive oxygen species and as well down-regulate the expressions of caspases 3 and 9. CONCLUSIONS: Vitamin C was observed to effectively protect chondrocytes against the toxic insult of local anesthetics ropivacaine, bupivacaine and lidocaine.


JUSTIFICATIVA: Injeções de anestésicos locais por via intra-articular são comumente usadas para melhorar a analgesia no período pós-operatório de cirurgia ortopédica como artroscopia. No entanto, relatos recentes de complicações graves devido ao uso de anestésico local por via intra-articular causou preocupações. OBJETIVOS: O objetivo do estudo foi avaliar o uso de vitamina C para reduzir os efeitos adversos dos anestésicos mais comumente usados (ropivocaína, bupivacaína e lidocaína) sobre condrócitos humanos. MÉTODOS: A viabilidade dos condrócitos após a exposição à bupivacaína a 0,5% ou ropivacaína a 0,75% ou lidocaína a 1,0% e/ou vitamina C em doses de 125, 250 e 500 µM foi determinada pelo ensaio Vivo/Morto e coloração com anexina V. Os níveis de expressão das caspases 3 e 9 foram avaliados com o uso de anticorpos pela técnica Western blotting. Citometria de fluxo foi feita para analisar a geração de espécies reativas ao oxigênio. RESULTADOS: Na exposição aos anestésicos locais, condrotoxicidade foi encontrada na seguinte ordem: ropivacaína < bupivacaína < lidocaína. A vitamina C efetivamente melhorou a redução da viabilidade dos condrócitos e diminuiu os níveis elevados de apoptose após a exposição à anestesia. Em doses mais altas, a vitamina C foi eficiente para reduzir a geração de espécies reativas ao oxigênio e assim regular negativamente a expressão das caspases 3 e 9. CONCLUSÕES: Observamos que a vitamina C foi eficaz na proteção dos condrócitos contra a agressão tóxica dos anestésicos locais ropivacaína, bupivacaína e lidocaína.


Subject(s)
Humans , Ascorbic Acid/pharmacology , Reactive Oxygen Species/metabolism , Chondrocytes/drug effects , Anesthetics, Local/toxicity , Ascorbic Acid/administration & dosage , Bupivacaine/toxicity , Down-Regulation/drug effects , Cells, Cultured , Apoptosis/drug effects , Chondrocytes/pathology , Dose-Response Relationship, Drug , Caspase 3/genetics , Caspase 9/genetics , Flow Cytometry , Ropivacaine , Amides/toxicity , Lidocaine/toxicity , Antioxidants/administration & dosage , Antioxidants/pharmacology
15.
São Paulo; s.n; 2016. 92 p. ilus, tab, graf. (BR).
Thesis in Portuguese | LILACS, BBO | ID: biblio-867989

ABSTRACT

Membranas celulares (MCs; Cell Sheets), constituídas por células-tronco (CTs), são autodestacáveis da placa de cultivo, e sem subcultivos geram grande quantidade de células que podem ser transplantadas de maneira mais próxima da fisiologia celular, mantendo-se as ligaçُões celulares e a matriz extracelular produzidas em cultura. O Ácido ascórbico ou vitamina C (VC) tem efeito indutor da formação destas MCs, aumentando a longevidade e tempo de indiferenciação das CTs. A similaridade observada entre respostas biológicas da VC em MCs e aquelas da Laserfototerapia (LFT) sobre células e tecidos, nos levou à hipótese de que estas terapias poderiam se complementar melhorando o prognóstico de futura aplicação clínica dessas MCs em regenerações tecidos de interesse odontológico. Para testar essa hipótese, LFT e VC foram aplicadas associadas ou não na indução de MCs de células-tronco da polpa dentária humana (hDPSCs). Para tanto, hDPSCs descongeladas, que expressaram níveis típicos de marcadores de superfície de células-tronco mesenquimais, foram plaqueadas em placas de 6 poços (5x104 células por poço). Vinte e quatro horas depois do plaqueamento as culturas foram submetidas aos tratamentos dos grupos experimentais: Controle: hDPSCs em P3 cultivadas com meio clonogênico; Senescente: hDPSCs em P27 cultivadas com meio clonogênico; VC: P3 cultivadas com meio clonogênico acrescido de VC (20µg/ml); Laser: P3 cultivadas com meio clonogênico e submetido à LFT (contato e pontual - 5 pontos / poço, 660 nm, 20 mW, 0,028 cm², 0,71 W/cm², 7 segundos, 5 J/cm², 0,14 J por ponto, 48 horas de intervalo) e Laser+VC: P3 cultivadas com meio clonogênico acrescido de VC e submetido


à LFT. Em 24 horas, 7 e 13 dias as hDPSCs dos diferentes grupos experimentais foram observadas macro e microscopicamente, e atividade da enzima telomerase foi avaliada por PCR-TRAP, complementado por ELISA. Para a avaliação da expressão de genes relacionados à natureza e indiferenciação (Mitofilina e Oct 4) e à longevidade (fase catalíca da enzima telomerase - hTERT); bem como à senescência das células do grupo senescente (­­ß-galactosidase), as hDPSCs de todos os grupos experimentais foram submetidas ao RT-qPCR As hDPSCs foram capazes de formar MCs somente nos grupos VC e Laser+VC (100%), entre 10 e 13 dias. As MCs do grupo Laser+VC apresentaram maior facilidade na manipulação. Atividade de Telomerase nas hDPSCs foi observada somente em 24 horas (Controle e LFT) e em 7 dias (VC e Laser+VC). Os marcadores de indiferenciação (Oct 4) e mesenquimal (mitofilina), bem como a hTERT foram expressos nas hDPSCs de todos os grupos experimentais. O Oct4 e o hTERT, em 7 dias, apresentaram expressões significativamente maiores nos grupos VC e Laser+VC em comparação com os demais (p < 0,0001, p = 0,0009, respectivamente). A expressão da mitofilina foi significativamente maior no grupo Laser+VC, em 7 dias (p =0,033). A técnica de obtenção de MCs de hDPSCs por essa metodologia foi considerada adequada para ser testada em procedimentos regenerativos. A LFT quando associada à VC não interferiu na formação das MCs, nem na manutenção da longevidade e indiferenciação das hDPSCs. Adicionalmente, a LFT melhorou a manipulação das MCs. Assim sendo, a associação de VC e LFT na indução de MCs parece promissora para futura utilização de MCs na odontologia regenerativa.


Cell Sheets, consisting of stem cells (SCs) are self detachable from the cultivation plate, and with no subcultivation can generate large amount of cells. The cell sheets can be transplanted closer to cell physiology environment by keeping the cell connections and the extracellular matrix produced in culture. Ascorbic acid or Vitamin C (VC) has inductive effect on cell sheet formation, increasing the longevity and the stemness of the cell for long period of time. The similarity between biological responses of VC in cell sheets and those of Laserphototherapy (LPT, Laser) on cells and tissues led us to hypothesize that these therapies could improve the prognosis of future clinical application of these cell sheets in regeneration of dental tissues. To test this hypothesis, LPT and VC were applied, associated or not, to induce human dental pulp stem cells (hDPSCs). Therefore, hDPSCs, which expressed typical levels of mesenchymal stem cell surface markers, were plated in 6-well plates (5x104 cells per well). Twenty-four hours later they were subjected to the treatment of experimental groups: Control: hDPSCs in P3 cultured with regular medium; Senescent: hDPSCs in P27 cultured with regular medium; VC: P3 cultured with regular medium supplemented with VC (20 ?g/ml); Laser: P3 cultures with regular medium and submitted to LPT (punctual and contact mode-5 points / well, 660 nm, 20 mW, 0.028 cm², 0.71 W/cm²,


7 sec, 5 J/cm², 0.14 J per point, 48 hours-intervals) and Laser+VC: P3 cultured with regular medium supplemented with VC and submitted to LPT Within 24 hours, 7 and 13 days the hDPSCs of the different experimental groups were observed macroscopically and microscopically, and the telomerase enzyme activity was assessed by PCR-TRAP, complemented by ELISA. To evaluate the expression of genes related to the nature and differentiation (Mitofilina and Oct 4), longevity (catalytic phase of telomerase-hTERT enzyme), and the senescence of the senescent group cells (?-galactosidase), the hDPSCs of all experimental groups were subjected to RT-qPCR. The RT-qPCR data were compared by ANOVA complemented by the Tukey's test (p <= 0.05). The hDPSCs were able to form cell sheets only in the VC and Laser+VC groups (100%). Additionally, the cell sheets of the Laser+VC group presented easier handling...


Subject(s)
Humans , Male , Female , Ascorbic Acid/administration & dosage , Ascorbic Acid/adverse effects , Stem Cells/classification , Lasers/adverse effects , Lasers , Cell Membrane/classification , Cell Membrane/genetics , Cell Membrane/metabolism , Regeneration , Stem Cells
17.
Gut and Liver ; : 237-243, 2016.
Article in English | WPRIM | ID: wpr-193423

ABSTRACT

BACKGROUND/AIMS: The aims of this study were to compare the bowel-cleansing efficacy, patient affinity for the preparation solution, and mucosal injury between a split dose of poly-ethylene glycol (SD-PEG) and low-volume PEG plus ascorbic acid (LV-PEG+Asc) in outpatient scheduled colonoscopies. METHODS: Of the 319 patients, 160 were enrolled for SD-PEG, and 159 for LV-PEG+Asc. The bowel-cleansing efficacy was rated according to the Ottawa bowel preparation scale. Patient affinity for the preparation solution was assessed using a questionnaire. All mucosal injuries observed during colonoscopy were biopsied and histopathologically reviewed. RESULTS: There was no significant difference in bowel cleansing between the groups. The LV-PEG+Asc group reported better patient acceptance and preference. There were no significant differences in the incidence or characteristics of the mucosal injuries between the two groups. CONCLUSIONS: Compared with SD-PEG, LV-PEG+Asc exhibited equivalent bowel-cleansing efficacy and resulted in improved patient acceptance and preference. There was no significant difference in mucosal injury between SD-PEG and LV-PEG+Asc. Thus, the LV-PEG+Asc preparation could be used more effectively and easily for routine colonoscopies without risking significant mucosal injury.


Subject(s)
Adult , Ascorbic Acid/administration & dosage , Cathartics/administration & dosage , Colonoscopy/methods , Drug Therapy, Combination , Female , Humans , Intestinal Mucosa/drug effects , Male , Middle Aged , Patient Compliance , Patient Satisfaction , Polyethylene Glycols/administration & dosage , Preoperative Care/adverse effects , Surveys and Questionnaires , Vitamins/administration & dosage
18.
Rev. Inst. Med. Trop. Säo Paulo ; 57(3): 245-250, May-Jun/2015. tab
Article in English | LILACS | ID: lil-752591

ABSTRACT

Introduction: In order to examine the effectiveness of vitamin C (ascorbic acid) in combating the oxidative insult caused by Trypanosoma cruzi during the development of the chronic phase of Chagas disease, Swiss mice were infected intraperitoneally with 5.0 × 104 trypomastigotes of T. cruzi QM1strain. Methods: Mice were given supplements of two different doses of vitamin C for 180 days. Levels of lipid oxidation (as indicated by thiobarbituric acid reactive substances-TBARS), total peroxide, vitamin C, and reduced glutathione were measured in the plasma, TBARS, total peroxide and vitamin C were measured in the myocardium and histopathologic analysis was undertaken in heart, colon and skeletal muscle. Results: Animals that received a dose equivalent to 500 mg of vitamin C daily showed increased production of ROS in plasma and myocardium and a greater degree of inflammation and necrosis in skeletal muscles than those that received a lower dose or no vitamin C whatsoever. Conclusion: Although some research has shown the antioxidant effect of vitamin C, the results showed that animals subject to a 500 mg dose of vitamin C showed greater tissue damage in the chronic phase of Chagas disease, probably due to the paradoxical actions of the substance, which in this pathology, will have acted as a pro-oxidant or pro-inflammatory. .


Introdução: Para verificar a eficácia da vitamina C em combater o insulto oxidativo causado pelo Trypanosoma cruzi durante a evolução da fase crônica da doença de Chagas, camundongos Swiss foram previamente infectados via intraperitoneal com 5.0 × 104 tripomastigotas da cepa QM1 de T. cruzi. Métodos: Camundongos foram suplementados com duas diferentes doses de vitamina C por 180 dias. Foram mensurados os níveis de peroxidação lipídica (indicado por substâncias reativas ao ácido tiobarbitúrico-TBARS), peróxido total, vitamina C, e glutationa reduzida no plasma e TBARS, peróxido total e vitamina C no miocárdio, e foi realizado o estudo histopatológico em coração, cólon e músculo esquelético. Resultados: Animais que receberam diariamente uma dosagem equivalente a 500 mg de vitamina C apresentaram aumento na produção de ROS e RNS no plasma e no miocárdio e maior grau de inflamação e necrose em músculo esquelético em comparação àqueles que receberam doses menores ou nenhuma vitamina C. Conclusão: Embora muitas pesquisas tenham mostrado o efeito antioxidante da vitamina C, nossos resultados mostraram que os animais que foram expostos a 500 mg de vitamina C apresentaram maior dano tecidual na fase crônica da doença de Chagas, provavelmente devido a ações paradoxais desta substância, onde nesta patologia, poderá agir como pró-oxidante ou pró-inflamatória. .


Subject(s)
Animals , Male , Mice , Antioxidants/administration & dosage , Ascorbic Acid/administration & dosage , Chagas Disease/drug therapy , Dietary Supplements , Biomarkers/blood , Chromatography, High Pressure Liquid , Chronic Disease , Chagas Disease/blood , Chagas Disease/pathology , Disease Models, Animal , Dose-Response Relationship, Drug , Glutathione/blood , Lipid Peroxidation , Nitric Oxide/blood , Peroxidase/blood , Thiobarbituric Acid Reactive Substances
19.
Rev. Assoc. Med. Bras. (1992) ; 61(3): 227-233, May-Jun/2015. tab
Article in English | LILACS | ID: lil-753166

ABSTRACT

Summary Objective: it is broadly accepted, but little explored, that obese children practice less physical activity and eat more. This study has the objective of comparing feeding habits and physical activity between eutrophic and overweight/obese children and adolescents. Methods: 126 students with ages ranging from 6 to 18 years were evaluated. Eutrophic and overweight/obese students were compared according to calorie intake, macro and micronutrients, prevalence of physical inactivity and ingestion of micronutrients. Results: differences were observed in the amount of calories ingested per unit of BMI (eutrophic, 97.6, and overweight/obese, 70.5, p=0.0061), as well as in calcium intake (eutrophic, 546.2, and overweight/obese, 440.7, p=0.0366). Both groups presented sedentarism, as well as a high prevalence of micronutrient intake deficiency, especially calcium and vitamins A, E, and C, but with no difference observed between eutrophic and overweight/obese subjects. Conclusion: energy and macronutrients consumption, as well as physical activity, were similar between eutrophic and overweight/obese. Calcium intake was lower in the overweight/obese group and the ingestion of vitamin C was lower in the eutrophic group. These results demonstrate the importance of considering all etiologic factors that may lead to obesity, so that new strategies for prevention and control may be added to traditional interventions. .


Resumo Objetivos: considera-se, em geral, que crianças obesas praticam menos atividade física e consomem mais alimentos, mas esse aspecto tem sido muito pouco explorado. O presente estudo objetivou comparar a alimentação e o padrão de atividade física de crianças e adolescentes eutróficos e portadores de sobrepeso/obesidade. Métodos: 126 estudantes com idades entre 6 e 18 anos foram avaliados por meio de antropometria, registro alimentar e grau de atividade física. Eutróficos e portadores de sobrepeso/obesidade foram comparados de acordo com a ingestão de calorias, macro e micronutrientes e de acordo com as prevalências de inatividade física e de ingestão deficiente de micronutrientes. Resultados: observou-se diferença na quantidade de calorias ingeridas por unidade de IMC (eutróficos 97,6 [92,2 - 112,5] e sobrepeso/obesidade 70,5 [72,2 - 90,8], p = 0,0061) e na ingestão de cálcio (eutróficos 546,2 [517,2 - 673,9] e sobrepeso/obesidade 440,7 [404,4 - 523,4], p = 0,0366). Os dois grupos apresentaram sedentarismo e elevada prevalência de deficiência na ingestão de micronutrientes, especialmente cálcio e vitaminas A, E e C, mas sem diferença entre eutróficos e portadores de sobrepeso/obesidade. Conclusões: consumo de energia e de macronutrientes e grau de atividade física foram semelhantes, quando comparados indivíduos eutróficos com portadores de sobrepeso/obesidade. O consumo de cálcio foi menor no grupo sobrepeso/obesidade e o de vitamina C menor no grupo eutróficos. Esses resultados mostram a importância de considerar todos os fatores etiológicos que podem levar à obesidade a fim de que possam associar-se novas estratégias de prevenção e controle às intervenções tradicionais. .


Subject(s)
Adolescent , Child , Female , Humans , Male , Feeding Behavior , Motor Activity , Micronutrients/administration & dosage , Overweight/etiology , Ascorbic Acid/administration & dosage , Body Mass Index , Cross-Sectional Studies , Calcium, Dietary/administration & dosage , Energy Intake , Life Style , Nutritional Status , Obesity/etiology , Sedentary Behavior , Surveys and Questionnaires
20.
Yonsei Medical Journal ; : 1449-1452, 2015.
Article in English | WPRIM | ID: wpr-39969

ABSTRACT

We report a case of regression of multiple pulmonary metastases, which originated from hepatocellular carcinoma after treatment with intravenous administration of high-dose vitamin C. A 74-year-old woman presented to the clinic for her cancer-related symptoms such as general weakness and anorexia. After undergoing initial transarterial chemoembolization (TACE), local recurrence with multiple pulmonary metastases was found. She refused further conventional therapy, including sorafenib tosylate (Nexavar). She did receive high doses of vitamin C (70 g), which were administered into a peripheral vein twice a week for 10 months, and multiple pulmonary metastases were observed to have completely regressed. She then underwent subsequent TACE, resulting in remission of her primary hepatocellular carcinoma.


Subject(s)
Aged , Antineoplastic Agents/administration & dosage , Ascorbic Acid/administration & dosage , Carcinoma, Hepatocellular/drug therapy , Chemoembolization, Therapeutic , Combined Modality Therapy , Female , Humans , Liver Neoplasms/pathology , Lung Neoplasms/drug therapy , Neoplasm Recurrence, Local , Niacinamide/analogs & derivatives , Phenylurea Compounds/therapeutic use , Treatment Outcome
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