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1.
Int. j. morphol ; 41(5): 1537-1549, oct. 2023. ilus, tab
Article Dans Anglais | LILACS | ID: biblio-1521025

Résumé

SUMMARY: Cisplatin (Cis) is an important chemotherapeutic agent used in cancer treatment. Males exposed to Cis were reported to exhibit testicular toxicity. Cis-induced testicular toxicity is mediated by oxidative stress, inflammation, testosterone inhibition and apoptosis. Accordingly, this study was conducted to evaluate the potential protective roles of infliximab (IFX), which is an anti- TNF-a agent, and of white tea (Camellia sinensis), which is known to possess antioxidant, anti-apoptotic, and anti-inflammatory effects, against Cis-induced testicular toxicity in rats. Rats were randomly assigned into five groups as follows: control group, Cisplatin (7 mg/kg) treatment group, Cisplatin (7 mg/kg) + infliximab (7 mg/kg) treatment group, cisplatin + white tea (WT) treatment group, and Cisplatin+ WT+IFX combined treatment group. In the present study, Cis exposure reduced the sperm count. It also increased testicular oxidative stress as well as the levels of inflammatory and apoptotic markers. Histopathological assays supported the biochemical findings. Treatment with IFX and/or WT restored testicular histology, preserved spermatogenesis, suppressed oxidative stress and apoptosis, and significantly ameliorated Cis-induced damage. It was concluded that white tea and infliximab could potentially serve as therapeutic options for the protection of testicular tissue against the harmful effects of Cis.


El cisplatino (Cis) es un importante agente quimioterapéutico utilizado en el tratamiento del cáncer. Se informó que los hombres expuestos a Cis exhibieron toxicidad testicular. La toxicidad testicular inducida por Cis está mediada por el estrés oxidativo, la inflamación, la inhibición de la testosterona y la apoptosis. En consecuencia, este estudio se realizó para evaluar las posibles funciones protectoras de infliximab (IFX), un agente anti-TNF-α, y del té blanco (Camellia sinensis), conocido por sus propiedades antioxidantes, antiapoptóticas y anti-TNF-α -efectos inflamatorios, contra la toxicidad testicular inducida por Cis en ratas. Cinco grupos de ratas se asignaron al azar de la siguiente manera: grupo control, grupo de tratamiento con cisplatino (7 mg/ kg), grupo de tratamiento con cisplatino (7 mg/kg) + infliximab (7 mg/kg), grupo de tratamiento con cisplatino + té blanco (WT), y grupo de tratamiento combinado Cisplatino+ WT+IFX. En el presente estudio, la exposición a Cis redujo el conteo de espermatozoides. También aumentó el estrés oxidativo testicular, así como los niveles de marcadores inflamatorios y apoptóticos. Los ensayos histopatológicos respaldaron los hallazgos bioquímicos. El tratamiento con IFX y/o WT restauró la histología testicular, preservó la espermatogénesis, suprimió el estrés oxidativo y la apoptosis, y mejoró significativamente el daño inducido por Cis. Se concluyó que el té blanco y el infliximab podrían potencialmente servir como opciones terapéuticas para la protección del tejido testicular contra los efectos nocivos de Cis.


Sujets)
Animaux , Mâle , Rats , Thé/composition chimique , Testicule/effets des médicaments et des substances chimiques , Extraits de plantes/pharmacologie , Cisplatine/toxicité , Camellia sinensis/composition chimique , Infliximab/pharmacologie , Numération des spermatozoïdes , Testicule/anatomopathologie , Immunohistochimie , Extraits de plantes/composition chimique , Facteur de nécrose tumorale alpha/antagonistes et inhibiteurs , Rat Sprague-Dawley , Apoptose , Stress oxydatif , Glutathion/analyse , Inflammation , Malonaldéhyde/analyse
2.
Arch. latinoam. nutr ; 72(3): 205-217, sept. 2022. ilus, tab, graf
Article Dans Espagnol | LILACS, LIVECS | ID: biblio-1399287

Résumé

Las catequinas del té verde (Camellia sinensis) (CTV) presentan efectos benéficos para la salud asociados a su potencial antioxidante. Por otra parte, el estrés oxidante es una de las vías de inducción de daño genotóxico. De ahí que, en la presente revisión se realizó un análisis de los efectos antigenotóxicos y genotóxicos de las CTV, haciendo énfasis en las vías implicadas en estos procesos y sus efectos en la salud. Se realizó una revisión de artículos indexados en las bases de datos de PubMed® y Science Direct® (2021) con las palabras clave "green tea" y "green tea catechins". Se delimitaron los estudios utilizando los operadores booleanos "AND", "OR" y "NOT" ("antigenotoxic", "genotoxic", "antioxidant" y "prooxidant"). En su mayoría se consideraron las publicaciones del 2016 al 2021. Se observó que los efectos benéficos en la salud de las CTV están relacionados con: a) su actividad antioxidante mediante la captura, inhibición y prevención de la formación de las especies reactivas de oxígeno; b) la regulación del sistema antioxidante endógeno; c) la activación de los mecanismos de reparación al contribuir en la eliminación del aducto 8-hidroxi-2'-desoxiguanosina; d) la inducción de apoptosis en células con daño al ADN; y e) la inhibición de la inflamación relacionada con su actividad antiapoptótica. Si bien, en algunos de los estudios se reportaron efectos genotóxicos, estos a su vez contribuyeron en la eliminación de células con daño genético, por lo que, no se puede considerar del todo a la actividad genotóxica de las CTV como perjudiciales para la salud(AU)


The green tea catechins (Camellia sinensis) (CTV) have beneficial effects for health associated with their antioxidant potential. Moreover, oxidative stress is one of the pathways for inducing genotoxic damage. Hence, in this review, an analysis of the antigenotoxic and genotoxic effects of CTV was carried out, emphasizing the pathways involved in these processes and their effects on health. A review of articles indexed in the PubMed® and ScienceDirect® (2021) databases with the keywords "green tea" and "green tea catechins" was carried out. Studies were delimited using the Boolean operators "AND", "OR" and "NOT" ("antigenotoxic", "genotoxic", "antioxidant" and "prooxidant"). For the most part, publications from 2016 to 2021 were considered. It was observed that the beneficial health effects of CTVs are related to: a) their antioxidant activity through the capture, inhibition and prevention of the formation of reactive oxygen species; b) the regulation of the endogenous antioxidant system; c) the activation of the repair mechanisms by contributing to the elimination of the 8-hydroxy-2'-deoxyguanosine adduct; d) the induction of apoptosis in cells with DNA damage; and e) the inhibition of inflammation related to its antiapoptotic activity. Although some of the studies reported genotoxic effects, these in turn contributed to the elimination of cells with genetic damage. Therefore, the genotoxic activity of CTV cannot be considered as harmful to health


Sujets)
Humains , Animaux , Thé/composition chimique , Catéchine/toxicité , Stress oxydatif/effets des médicaments et des substances chimiques , Génotoxicité , Antioxydants/toxicité , Altération de l'ADN/effets des médicaments et des substances chimiques , Espèces réactives de l'oxygène , Apoptose/effets des médicaments et des substances chimiques
3.
Chinese Journal of Biotechnology ; (12): 4731-4743, 2022.
Article Dans Chinois | WPRIM | ID: wpr-970344

Résumé

The tea beverages will be endowed with distinct aroma and taste, as well as various biologically active compounds including probiotic factors, when fermented with lactic acid bacteria (LAB). However, at present, few studies on the dynamics of flavors in tea soup at different fermentation stages were conducted. In this study, the composition of monosaccharides, aromatic components, free amino acids, and organic acids were measured, when the black tea beverages were fermented with Lactobacillus coryniformis FZU63 which was isolated from Chinese traditional kimchi. The results indicated that monosaccharides including glucose, fructose, mannose and xylose in black tea beverages are the main carbon sources for fermentation. In addition, the abundance of aromatic compounds in black tea soup are increased significantly at different fermentation stages, which endow the fermented black tea soup with fruit aroma on the basis of flowery and nutty aroma. Moreover, some bitter amino acids are reduced, whereas the content of sweet and tasty amino acids is elevated. Furthermore, the levels of lactic acid, malic acid, citric acid and other organic acids are accumulated during the fermentation. Additionally, sensory evaluation displays that black tea beverage is acquired with comprehensive high-quality after being fermented for 48 h. This study provides a theoretical basis to steer and control the flavor formation and quality of the fermented tea beverages during LAB fermentation.


Sujets)
Thé/composition chimique , Boissons/microbiologie , Camellia sinensis , Fermentation , Acides , Acides aminés , Glucose
4.
Int. j interdiscip. dent. (Print) ; 14(2): 158-161, ago. 2021. tab, graf
Article Dans Espagnol | LILACS | ID: biblio-1385206

Résumé

RESUMEN: Objetivo: Determinar la estabilidad cromática de una cerámica de feldespato monocromática utilizada en sistema CAD/CAM sometida a inmersión de diferentes soluciones de tinción. Materiales y métodos: 90 discos de cerámica feldespática monocromática, divididos en 3 grupos según solución de tinción: agua destilada, café y té. Se realizaron 3 tomas de color: el día 0, 14 y 28, con un espectrofotómetro. Para determinar la diferencia de color (ΔE*), se restó la 2da y la 1era medida para los 14 días; y la 3era y la 2da medida para los 28 días. Resultados: Los resultados se interpretaron utilizando el Índice del Departamento Nacional de Normas (NBS). La muestra inmersa en agua destilada presentó valores ΔE* 1.424 y ΔE* 1.233; la muestra en café presentó valores ΔE* 3.327 y ΔE* 3.901; la muestra inmersa en té presentó valores ΔE* 4.597 y ΔE* 5.201. Se obtuvieron diferencias significativas al comparar la estabilidad cromática en las tres soluciones de tinción a los 14 y 28 días (p<0.001). Conclusiones: Existe diferencia significativa en la estabilidad cromática de una cerámica de feldespato monocromática sometida a inmersión de diferentes soluciones de tinción. Se obtuvieron cambios de color marcados en las muestras inmersas en café y en té.


ABSTRACT: Objective: Determine the color stability of a monochromatic feldspathic ceramic used in CAD / CAM system subjected to immersion in different staining solutions. Methods and materials: 90 monochromatic feldspathic ceramic discs were divided into 3 groups according to staining solution: distilled water, coffee and tea. Three color samples were taken: on days 0, 14 and 28, with a spectrophotometer. To determine the color difference (ΔE *), the 2nd and 1st measure were subtracted for the 14 days; and the 3rd and 2nd measure for the 28 days. Results: The results were interpreted using the National Standards Department Index (NBS). The sample immersed in distilled water presented values ΔE * 1,424 and ΔE * 1,233; the sample in coffee presented values ΔE * 3,327 and ΔE * 3,901; the sample immersed in tea presented values ΔE * 4,597 and ΔE * 5,201. Significant differences were obtained when comparing the chromatic stability in the three staining solutions at 14 and 28 days (p <0.001). Conclusion: There is a significant difference in the chromatic stability of a monochromatic feldspar ceramic subjected to immersion in different staining solutions. Marked color changes were obtained in the samples immersed in coffee and tea.


Sujets)
Humains , Céramiques/composition chimique , Spectrophotométrie , Thé/composition chimique , Test de matériaux , Conception assistée par ordinateur , Café/composition chimique , Immersion
5.
Braz. arch. biol. technol ; 63: e20180413, 2020. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1132167

Résumé

Abstract: Freshly prepared apple tea wine (a combination of tea extract and apple juice) is having yeasty and dull flavour, which needs to be improved to increase the acceptability of this product. Therefore, an attempt has been made for artificial ageing of apple tea wine using different wood chips to improve its physico-chemical, sensory and antimicrobial attributes. Different types of wood chips (Quercus spp., Bombax spp. and Acacia spp.) were added respectively (2.5 g/L to the freshly prepared apple tea wine) and allowed for ageing in carboys for the six months at the room temperature. The influence of each wood species on physico-chemical, sensory and antimicrobial attributes was tested upto 6 months of storage. Storage intervals significantly affected all the physico-chemical attributes (except total sugars, volatile acidity, and antioxidant activity), whereas, the addition of wood chips affected titratable acidity, ethanol, higher alcohols, total phenols, and amino acid. Cluster analysis of the physico-chemical attributes data revealed the same and showed that storage intervals exerted more effect on the physico-chemical and antimicrobial properties of the apple tea wine rather than the wood chips. The antimicrobial activity of 6 months aged wine was low as compared to the fresh wine. Among all the wood chips, apple tea wine aged with Quercus spp. possesses a significantly higher score (according to desirability) than the wine aged with other wood chips and control. In nutshell, apple tea wine matured with Quercus spp. wood chips for 6 months were the best with improved physico-chemical and sensory attributes.


Sujets)
Humains , Thé/composition chimique , Vin/analyse , Malus/composition chimique , Jus , Antibactériens/pharmacologie , Phénomènes chimiques
6.
Int. j. morphol ; 37(4): 1325-1330, Dec. 2019. graf
Article Dans Anglais | LILACS | ID: biblio-1040132

Résumé

Impairing osteoporosis progression is a challenge, and recently the role of antioxidants has been associated to bone metabolism. Green tea extract is rich in catechins, especially epigallocatechin gallate (EGCG), which may help control osteoporosis damage in bone tissue. This investigation evaluated the efficacy of green tea ingestion containing different concentrations of EGCG in calvaria bone repair of ovariectomized rats. Wistar rats (n=15) were ovariectomized and divided into 3 groups: ovariectomized (OVX), ovariectomized + GTE 15 % EGCG (OVX/GTE15), and ovariectomized + GTE 94 % EGCG (OVX/GTE94). Green tea extract was administered by gavage in the concentration of 50 mg/kg and sham group (n=5) received water. Bone defects were performed in the calvaria 60 days after ovariectomy followed by 4 weeks until euthanasia. Bone samples were collected to perform qualitative and quantitative histological analysis of bone formation. Data obtained were submitted to normality and ANOVA statistical test for p<0.05. The mean values of neoformed bone for Sham, OVX, OVX/GTE15 and OVX/GTE94 were respectively: 21.11 ± 3.91; 19.92 ± 2.20; 33.05 ± 1.26 e 34.75 ± 0.54 (p<0.05). Results show that continuous ingestion of green tea extract immediately after ovariectomy shows positive effects in the prevention of bone loss in osteoporosis, even with low concentrations of EGCG.


La disminución en la progresión de la osteoporosis es un desafío, y recientemente el papel de los antioxidantes se ha asociado al metabolismo óseo. El extracto de té verde es rico en catequinas, especialmente el galato de epigalocatequina (EGCG), lo que puede ayudar a controlar el daño de la osteoporosis en el tejido óseo. Esta investigación evaluó la eficacia de la ingesta de té verde con diferentes concentraciones de EGCG en la reparación ósea de calvaria de ratas ovariectomizadas. Las ratas Wistar (n = 15) fueron ovariectomizadas y divididas en 3 grupos: ovariectomizadas (OVX), ovariectomizadas + GTE 15 % EGCG (OVX / GTE15), y ovariectomizadas + GTE 94 % EGCG (OVX / GTE94). El extracto de té verde se administró por sonda en una concentración de 50 mg/kg y el grupo simulado (n = 5) recibió agua. Los defectos óseos se realizaron en la calvaria 60 días después de la ovariectomía, seguido de 4 semanas hasta la eutanasia. Se obtuvieron muestras de hueso para realizar un análisis histológico cualitativo y cuantitativo de la formación ósea. Los datos obtenidos se sometieron a normalidad y prueba estadística ANOVA (p<0,05). Los valores medios de hueso neoformado para Sham, OVX, OVX / GTE15 y OVX / GTE94 fueron: 21,11 ± 3,91; 19,92 ± 2,20; 33,05 ± 1,26 y 34,75 ± 0,54 (p <0,05), respectivamente. Los resultados muestran que la ingesta continua de extracto de té verde, inmediatamente después de la ovariectomía, muestra efectos positivos en la prevención de la pérdida ósea ocurrida en la osteoporosis, incluso con concentraciones bajas de EGCG.


Sujets)
Animaux , Femelle , Rats , Thé/composition chimique , Régénération osseuse , Extraits de plantes/pharmacologie , Catéchine/analogues et dérivés , Catéchine/métabolisme , Ostéoporose/anatomopathologie , Ostéoporose/traitement médicamenteux , Extraits de plantes/usage thérapeutique , Ovariectomie , Rat Wistar
7.
Braz. j. med. biol. res ; 51(4): e6891, 2018. graf
Article Dans Anglais | LILACS | ID: biblio-889070

Résumé

Gallbladder cancer (GBC) is the most common malignancy in the biliary tract. Without effective treatment, its prognosis is notoriously poor. Tea polyphenols (TPs) have many pharmacological and health benefits, including antioxidant, anti-inflammatory, anti-tumor, anti-thrombotic, antibacterial, and vasodilatory properties. However, the anti-cancer effect of TPs in human gallbladder cancer has not yet been determined. Cell viability and colony formation assay were used to investigate the cell growth. Cell cycle and apoptosis were evaluated by flow cytometry analysis. Western blot assay was used to detect the expression of proteins related to cell cycle and apoptosis. Human tumor xenografts were used to examine the effect of TPs on gallbladder cancer cells in vivo. TPs significantly inhibited cell growth of gallbladder cancer cell lines in a dose- and time-dependent manner. Cell cycle progression in GBC cells was blocked at the S phase by TPs. TPs also induced mitochondrial-related apoptosis in GBC cells by upregulating Bax, cleaved caspase-3, and cleaved PARP expressions and downregulating Bcl-2, cyclin A, and Cdk2 expressions. The effects of TPs on GBC were further proven in vivo in a mouse xenograft model. Our study is the first to report that TPs inhibit GBC cell growth and these compounds may have potential as novel therapeutic agents for treating gallbladder cancer.


Sujets)
Humains , Antinéoplasiques d'origine végétale/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Camellia sinensis/composition chimique , Tumeurs de la vésicule biliaire/anatomopathologie , Polyphénols/pharmacologie , Phase S/effets des médicaments et des substances chimiques , Thé/composition chimique , Antinéoplasiques d'origine végétale/isolement et purification , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Tumeurs de la vésicule biliaire/traitement médicamenteux , Hétérogreffes , Polyphénols/isolement et purification
8.
Braz. oral res. (Online) ; 32: e40, 2018. tab, graf
Article Dans Anglais | LILACS | ID: biblio-889471

Résumé

Abstract This research explored the potential of Camellia sinensis-derived teas and active compounds to be used as treatments to prevent dentin wear. Human root dentin slabs were randomly assigned to 5 groups (n = 10) as follows: distilled water (DW, control), epigallocatechin-3-gallate (EGCG), theaflavin gallate derivatives (TF), commercial green tea (GT), and commercial black tea (BT). The samples were submitted to a pellicle formation and an erosive cycling model (5x/day, demineralization using 0.01 M hydrochloric acid/60 s) followed by remineralization (human stimulated saliva/60 min) for three days. The samples were treated for 5 min using the test group solutions between the erosive cycles. Dentin changes were assessed with profilometry analysis and FT-Raman spectroscopy. The data regarding wear were analyzed by ANOVA followed by Tukey's test (p < 0.05). EGCG, TF derivatives, and both regular teas significantly suppressed erosive dentin loss (38-47%, p < 0.05). No obvious changes in the Raman spectra were detected in the specimens; however, the DW group had a minor relationship of 2880/2940 cm−1. The phenolic contents in both green and black tea and the important catechins appear to have protective effects on dentin loss.


Sujets)
Humains , Biflavonoïdes/pharmacologie , Camellia sinensis/composition chimique , Catéchine/analogues et dérivés , Dentine/effets des médicaments et des substances chimiques , Acide gallique/analogues et dérivés , Thé/composition chimique , Érosion dentaire/prévention et contrôle , Catéchine/pharmacologie , Fluorures/analyse , Fluorures/pharmacologie , Acide gallique/pharmacologie , Eau/composition chimique
9.
Hig. aliment ; 31(270/271): 92-96, 29/08/2017.
Article Dans Portugais | LILACS | ID: biblio-848947

Résumé

Os Antioxidantes são substancias que retardam o aparecimento de alterações oxidativas tanto nos seres vivos como nos alimentos. Quimicamente, são compostos aromáticos que contém em sua estrutura, pelo menos, um grupamento hidroxila. Estes podem ser naturais ou sintéticos, sendo o último amplamente utilizado na indústria alimentícia como conservante. O consumo de alimentos ricos em antioxidantes, como chás, vinhos e frutos foi relacionado com a baixa incidência de doenças degenerativas. Assim, objetivou-se neste estudo investigar a atividade antioxidante de chás processados frente ao DPPH (1,1-Diphenyl-2-picryl- hydrazyl). Para tanto, selecionaram- se 05 tipos de chá processados, comercializados no comercio formal da cidade de Teresina, Piauí, Brasil. A determinação da Atividade Antioxidante Total (AAT) se deu a partir dos extratos etanólicos obtidos das amostras com leituras em espectrofotômetro a 517nm. Os resultados revelam uma distribuição da ATT nas amostras variando de 19 a 84%. Observou-se, ainda, que o Boldo do Chile registrou a maior média dentre os demais. De uma forma geral, os chás são uma boa fonte de antioxidantes.(AU)


Sujets)
Humains , Thé/composition chimique , Antioxydants/analyse , Antioxydants/usage thérapeutique , Extraits de plantes , Qualité alimentaire
10.
Electron. j. biotechnol ; 28: 87-94, July. 2017. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1015957

Résumé

Background: Inferior Tieguanyin oolong tea leaves were treated with tannase. The content and bioactivity of catechins in extracts from the treated tea leaves were investigated to assess the improvement in the quality of inferior Tieguanyin oolong tea. Results: Analysis showed that after treatment, the esterified catechin content decreased by 23.5%, whereas non-galloylated catechin and gallic acid contents increased by 15.3% and 182%, respectively. The extracts from tannase-treated tea leaves showed reduced ability to bind to BSA and decreased tea cream levels. The extracts also exhibited increased antioxidant ability to scavenge OH and DPPH radicals, increased ferric reducing power, and decreased inhibitory effects on pancreatic α-amylase and lipase activities. Conclusions: These results suggested that tannase treatment could improve the quality of inferior Tieguanyin oolong tea leaves.


Sujets)
Thé/enzymologie , Carboxylic ester hydrolases/métabolisme , Thé/métabolisme , Thé/composition chimique , Température , Catalyse , Catéchine/analyse , Feuilles de plante/enzymologie , Fermentation , Hydrolyse , Triacylglycerol lipase/antagonistes et inhibiteurs , Triacylglycerol lipase/métabolisme , Antioxydants
11.
J. appl. oral sci ; 24(3): 211-217, tab, graf
Article Dans Anglais | LILACS, BBO | ID: lil-787537

Résumé

ABSTRACT Objective Green tea extract has been advocated as a matrix metalloproteinase (MMP) inhibitor; however, its effect on bond durability to caries-affected dentin has never been reported. Thus, the aim of this in vitro study was to evaluate the effect of two MMP inhibitors (2% chlorhexidine and 2% green tea extract), applied after acid etching, on bond durability of an etch-and-rinse adhesive system to caries-affected dentin. Material and Methods Occlusal enamel was removed from third molars to expose the dentin surface, and the molars were submitted to a caries induction protocol for 15 days. After removal of infected dentin, specimens were conditioned with 37% phosphoric acid (15 seconds) and randomly divided into three groups, according to the type of dentin pretreatment (n=10): NT: no treatment; GT: 2% green tea extract; CLX: 2% chlorhexidine. The etch-and-rinse adhesive system (Adper™ Single Bond 2, 3M ESPE, St. Paul, MN, USA) was applied according to the manufacturer's instructions, and composite resin restorations were built on the dentin. After 24 hours, at 37°C, the resin-tooth blocks were sectioned perpendicularly to the adhesive interface in the form of sticks (0.8 mm2 of adhesive area) and randomly subdivided into two groups according to when they were to be submitted to microtensile bond strength (μTBS) testing: immediately or 6 months after storage in distilled water. Data were reported in MPa and submitted to two-way ANOVA for completely randomized blocks, followed by Tukey’s test (α=0.05). Results After 24 hours, there was no significant difference in the μTBS of the groups. After 6 months, the GT group had significantly higher μTBS values. Conclusion It was concluded that the application of 2% green tea extract was able to increase bond durability of the etch-and-rinse system to dentin. Neither the application of chlorhexidine nor non-treatment (NT - control) had any effect on bond strength after water storage.


Sujets)
Humains , Acides phosphoriques/composition chimique , Thé/composition chimique , Chlorhexidine/composition chimique , Caries dentaires/traitement médicamenteux , Ciments dentaires/composition chimique , Dentine/effets des médicaments et des substances chimiques , Anti-infectieux locaux/composition chimique , Propriétés de surface , Résistance à la traction , Facteurs temps , Mordançage à l'acide/méthodes , Test de matériaux , Répartition aléatoire , Reproductibilité des résultats , Analyse de variance , Collage dentaire/méthodes , Agents de collage dentinaire/composition chimique
12.
Braz. j. biol ; 76(2): 428-434, Apr.-June 2016. tab, graf
Article Dans Anglais | LILACS | ID: lil-781392

Résumé

Abstract The antioxidant and anticandidal activities of leaves obtained from Camellia sinensis by non-fermentation (green and white teas), semi-fermentation (red tea) and fermentation method (black tea) were investigated. It was evaluated the total phenolic content by Folin-Ciocalteau assay; antioxidant capacities were evaluated in vitro using DPPH and ABTS radicals, hypochlorous acid and superoxide anion scavenger assays, induced hemolysis, lipid peroxidation by conjugated diene formation and myeloperoxidase activity. Anticandidal activity was performed on three strains of Candida spp. The results showed that non-fermented teas have a higher concentration of phenolic compounds, and then presented the best inhibitory activity of AAPH-induced hemolysis, the best inhibition of conjugated diene formation and more pronounced antioxidant activity in all tests. The highest anticandidal activity was obtained from fermented tea, followed by non-fermented tea. These results indicate that the antioxidant activity demonstrated has no direct relation with the anticandidal activity.


Resumo A atividade antioxidante e antifúngica das folhas obtidas da Camellia sinensis pelos métodos de não-fermentação (chás verde e branco), semi-fermentação (chá vermelho) e fermentação (chá preto) foram investigadas. Foi avaliado o conteúdo total de compostos fenólicos pelo método de Folin-Ciocalteau; a capacidade antioxidante foi avaliada in vitro usando os radicais artificiais DPPH e ABTS, o ácido hipocloroso, ensaios do ânion superóxido, hemólise induzida, peroxidação lipídica por formação de dienos conjugados e atividade da Mieloperoxidase. A atividade antifúngica foi obtida sobre três cepas de Candida spp. Os resultados obtidos mostram que os chás não fermentados apresentam a maior concentração de compostos fenólicos e também, apresentam a melhor atividade inibitória, sobre hemólise induzida por APPH, sobre a formação de dienos conjugados e a mais pronunciada atividade antioxidante sobre todos os testes. A maior atividade antifúngica foi obtida pelo chá fermentado, seguido pelo semi-fermentado e não-fermentados. Os resultados obtidos demonstram que a atividade antioxidante observada não apresenta relação com a atividade antifúngica.


Sujets)
Feuilles de plante/composition chimique , Camellia sinensis/composition chimique , Antifongiques/pharmacologie , Antioxydants/pharmacologie , Oxydoréduction , Phénols/analyse , Thé/composition chimique , Extraits de plantes , Peroxydation lipidique , Myeloperoxidase/métabolisme , Fermentation , Hémolyse , Antifongiques/analyse , Antioxydants/analyse
13.
Braz. oral res. (Online) ; 30(1): e13, 2016. tab, graf
Article Dans Anglais | LILACS | ID: lil-768259

Résumé

Abstract The aim of this study was to evaluate the effect of green tea as a protective measure on eroded dentin. Disks of human coronary dentin were selected based on surface hardness and randomly assigned to 3 groups (n = 10): DW - distilled water, CHX - 0.2% chlorhexidine digluconate, and GT - green tea. The disks were allowed to acquire pellicle for 2 hours and were then subjected to 3 cycles per day of demineralization (C6H8O7 0.05 M, pH 3.75, 60 s), treatment (DW or CHX or GT, 5 min) and remineralization (artificial saliva, 60 min) over a period of 3 days. Changes in the dentin were determined by loss of surface hardness (%SHL) and mechanical profilometry analysis at the end of each day. Data were analyzed by two-way ANOVA followed by Tukey’s test for %SHL and profilometry (p < 0.05). Significant reductions in dentin hardness loss were observed only for the CHX group when compared to the DW group (p < 0.05). However, there was no significant difference between the CHX and GT groups (p > 0.05). A significant difference was observed between DW and GT treatments for wear and roughness measurements (p < 0.05). The green tea extract solution was able to reduce the wear and roughness caused by dentin erosion under the conditions of this study.


Sujets)
Humains , Dentine/effets des médicaments et des substances chimiques , Agents protecteurs/composition chimique , Thé/composition chimique , Érosion dentaire/prévention et contrôle , Analyse de variance , Chlorhexidine/analogues et dérivés , Chlorhexidine/composition chimique , Dureté , Matrix metalloproteinases/composition chimique , Extraits de plantes/composition chimique , Répartition aléatoire , Reproductibilité des résultats , Salive artificielle/composition chimique , Statistique non paramétrique , Propriétés de surface/effets des médicaments et des substances chimiques , Facteurs temps , Eau/composition chimique
14.
Acta cir. bras ; 30(4): 242-246, 04/2015. graf
Article Dans Anglais | LILACS | ID: lil-744278

Résumé

PURPOSE: To evaluate the anti-inflammatory and analgesic effects of green tea (Camellia sinensis) in mice. METHODS: The anti-inflammatory effect of alcoholic extracts of green tea (AE) was evaluated in a cell migration assay with four groups of six Swiss mice receiving 0.07g/Kg or 0.14g/Kg EA (treatment groups), saline (negative control) or 10mg/Kg indomethacin (positive control) by gavage. One hour later 300 µg carrageen an was administered intraperitoneally or subcutaneously. The analgesic effect was evaluated using four groups of six animals receiving 0.07g/Kg or 0.14g/Kg EA, saline or 10mg/Kg indomethacin subcutaneously, followed 30 minutes later by 1% acetic acid. RESULTS: When administered subcutaneously at either dose (0.07g/Kg and 0.14g/Kg), AE inhibited carrageenan-induced cell migration (p<0.05). However, when administered by gavage, only the latter (0.14 g/Kg) was efficient (p<0.05). AE at both doses (0.07g/Kg and 0.14g/Kg) inhibited abdominal contortions (p<0.05), but the effect was not dose-dependent. CONCLUSION: Green tea was shown to have analgesic and anti-inflammatory properties and may constitute a natural treatment option in chronic inflammatory disorders. .


Sujets)
Animaux , Mâle , Souris , Analgésiques/usage thérapeutique , Anti-inflammatoires/usage thérapeutique , Camellia sinensis/composition chimique , Phytothérapie/méthodes , Extraits de plantes/usage thérapeutique , Thé/composition chimique , Tests de migration cellulaire , Catéchine/usage thérapeutique , Perfusions sous-cutanées , Indométacine/usage thérapeutique , Inflammation/traitement médicamenteux , Reproductibilité des résultats , Facteurs temps , Résultat thérapeutique
15.
Journal of Veterinary Science ; : 135-143, 2015.
Article Dans Anglais | WPRIM | ID: wpr-44469

Résumé

Tea contains polyphenols and is one of the most popular beverages consumed worldwide. Because most tyrosinase inhibitors that regulate melanogenesis are phenol/catechol derivatives, this study investigated the inhibitory effects of Camellia sinensis water extracts (CSWEs), including black tea, green tea, and white tea extracts, on melanogenesis using immortalized melanocytes. CSWEs inhibited melanin accumulation and melanin synthesis along with tyrosinase activity in a concentration-dependent manner. These inhibitory effects were superior to those of arbutin, a well-known depigmenting agent. The anti-melanogenic activity of black (fermented) tea was higher than that of a predominant tea catecholamine, epigallocatechin gallate. CSWEs, especially black tea extract, decreased tyrosinase protein levels in a concentration-dependent manner. These results suggest that the anti-melanogenic effect of CSWEs is mediated by a decrease in both tyrosinase activity and protein expression, and may be augmented by fermentation. Thus, CSWEs could be useful skin-whitening agents in the cosmetic industry.


Sujets)
Animaux , Souris , Catéchine/analogues et dérivés , Lignée cellulaire , Mélanines/métabolisme , Mélanocytes/enzymologie , Monophenol monooxygenase/métabolisme , Extraits de plantes/pharmacologie , Feuilles de plante/composition chimique , Thé/composition chimique
16.
Arq. gastroenterol ; 51(3): 255-260, Jul-Sep/2014. tab, graf
Article Dans Anglais | LILACS | ID: lil-723856

Résumé

Objectives Panax ginseng, Camellia sinensis and bezafibrate were compared for their lipid-lowering, antioxidant and anti-inflammatory properties as potential agents to prevent nonalcoholic fatty liver disease and its progression to nonalcoholic steatohepatitis. Methods Fifty Wistar rats were randomized into five groups: G1 (feed with standard diet); G2 (feed with high-fat diet with 58% of energy from fat); G3 (high-fat diet + standardized Panax ginseng extract at 100 mg/kg/day); G4 (high-fat diet + standardized Camellia sinensis extract at 100 mg/kg/day); and G5 (high-fat diet + bezafibrate at 100 mg/kg/day), given by gavage. The animals were sacrificed eight weeks later and blood was collected for glucose, insulin, cholesterol, triglycerides, AST, ALT, alkaline phosphatase and gamma-glutamyl transferase determinations. The score system for nonalcoholic fatty liver disease was used to analyse the liver samples. Results and conclusions High-fat diet resulted in a significant increase in animal body weight, biochemical changes and enzymatic elevations. Steatosis, inflammation and hepatocellular ballooning scores were significant high in this group. The biochemical and histological variables were statistically similar in the bezafibrate group and control group. Treatment with Panax ginseng extract prevented obesity and histological features of nonalcoholic steatohepatitis (steatosis and inflammation) compared to high-fat diet. Camellia sinensis showed a less effective biochemical response, with small reduction in steatosis and inflammation but lower ballooning scores. .


Objetivos Panax ginseng, Camellia sinensis e bezafibrato foram comparados por suas propriedades hipolipemiantes, antioxidantes e anti-inflamatórias, como potenciais agentes capazes de prevenir a doença hepática gordurosa não alcoólica e sua progressão para esteato-hepatite não alcoólica. Métodos Cinqüenta ratos Wistar foram distribuídos aleatoriamente em cinco grupos: G1 (alimentados com dieta padrão); G2 (alimentados com dieta hipercalórica com 58% de energia a partir de gordura); G3 (dieta rica em gordura + extrato padronizado Panax ginseng em 100 mg / kg / dia); G4 (dieta rica em gordura + extrato de Camellia sinensis padronizado a 100 mg / kg / dia); e G5 (dieta rica em gordura + bezafibrato, a 100 mg / kg / dia), administrado via oral. Os animais foram sacrificados após oito semanas e o sangue foi coletado para determinação da glicose, insulina, colesterol, triglicérides, AST, ALT, fosfatase alcalina e gama-glutamil transferase. O sistema NAS de pontuação para doença hepática gordurosa não alcoólica foi utilizado para analisar as amostras de fígado. Resultados e conclusões A dieta hipercalórica resultou em um aumento significativo no peso corporal dos animais, associado a alterações bioquímicas e elevações enzimáticas. Os escores de esteatose, inflamação e balonização hepatocelular foram significativamente mais elevados neste grupo. As variáveis bioquímicas e histológicas foram estatisticamente semelhantes entre os grupos bezafibrato e controle. O uso do extrato do Panax ginseng esteve associado a um menor ganho de peso dos animais, em média, bem como a menores índices nos escores de esteato-hepatite (esteatose e inflamação) em comparação com o grupo apenas alimentado com dieta hipercalórica. No grupo ...


Sujets)
Animaux , Acides fibriques/administration et posologie , Stéatose hépatique non alcoolique/prévention et contrôle , Panax/composition chimique , Phytothérapie/méthodes , Thé/composition chimique , Évolution de la maladie , Répartition aléatoire , Rat Wistar
17.
Dental press j. orthod. (Impr.) ; 19(4): 114-121, Jul-Aug/2014. tab, graf
Article Dans Anglais | LILACS | ID: lil-725426

Résumé

OBJECTIVE: The aim of this in vitro study was to analyze color stability of monocrystalline and polycrystalline ceramic brackets after immersion in dye solutions. METHODS: Seven ceramic brackets of four commercial brands were tested: Two monocrystalline and two polycrystalline. The brackets were immersed in four dye solutions (coffee, red wine, Coke and black tea) and in artificial saliva for the following times: 24 hours, 7, 14 and 21 days, respectively. Color changes were measured by a spectrophotometer. Data were assessed by Multivariate Profile Analysis, Analysis of Variance (ANOVA) and Multiple Comparison Tests of means. RESULTS: There was a perceptible change of color in all ceramic brackets immersed in coffee (ΔE* Allure = 7.61, Inspire Ice = 6.09, Radiance = 6.69, Transcend = 7.44), black tea (ΔE* Allure = 6.24, Inspire Ice = 5.21, Radiance = 6.51, Transcend = 6.14) and red wine (ΔE* Allure = 6.49, Inspire Ice = 4.76, Radiance = 5.19, Transcend = 5.64), but no change was noticed in Coke and artificial saliva (ΔE < 3.7). CONCLUSION: Ceramic brackets undergo color change when exposed to solutions of coffee, black tea and red wine. However, the same crystalline structure, either monocrystalline or polycrystalline, do not follow the same or a similar pattern in color change, varying according to the bracket fabrication, which shows a lack of standardization in the manufacturing process. Coffee dye produced the most marked color changes after 21 days of immersion for most ceramic brackets evaluated. .


OBJETIVO: esse estudo objetivou analisar, in vitro, a estabilidade de cor de braquetes cerâmicos monocristalinos e policristalinos após imersão em soluções corantes. MÉTODOS: sete braquetes cerâmicos de incisivo central superior direito, de quatro marcas comerciais, foram testados: dois monocristalinos e dois policristalinos. Os braquetes foram imersos em quatro soluções corantes (café, vinho tinto, Coca-Cola e chá preto) e em saliva artificial, separadamente, nos seguintes tempos: 24 horas, 7, 14 e 21 dias. As alterações de cor foram mensuradas por espectrofotômetro de refletância. Os dados foram avaliados pela Análise de Perfis Multivariados, Análise de Variância e teste de comparação múltipla de médias. RESULTADOS: houve alteração perceptível de cor em todos os braquetes cerâmicos após 21 dias de imersão nas soluções de café (ΔE* Allure = 7,61; Inspire Ice = 6,09; Radiance = 6,69; Transcend = 7,44), chá preto (ΔE* Allure = 6,24; Inspire Ice = 5,21; Radiance = 6,51; Transcend = 6,14) e vinho tinto (ΔE* Allure = 6,49; Inspire Ice = 4,76; Radiance = 5,19; Transcend = 5,64), porém, a alteração não foi perceptível para a Coca-Cola e saliva artificial (ΔE* < 3,7). CONCLUSÃO: braquetes cerâmicos sofrem alteração de cor quando em contato com café, chá preto e vinho tinto. No entanto, os braquetes de mesma constituição cristalina, sejam monocristalinos ou policristalinos, não seguem um padrão semelhante de alteração de cor, mas variam de acordo com o fabricante, o que mostra uma falta de padronização no processo de produção desses braquetes. O café foi a solução corante que mais produziu alteração de cor após 21 dias ...


Sujets)
Humains , Céramiques/composition chimique , Matériaux dentaires/composition chimique , Brackets orthodontiques , Boissons gazeuses , Couleur , Cristallisation , Café/composition chimique , Concentration en ions d'hydrogène , Immersion , Test de matériaux , Spectrophotométrie , Propriétés de surface , Salive artificielle/composition chimique , Température , Facteurs temps , Thé/composition chimique , Vin
18.
Arch. latinoam. nutr ; 63(3): 247-253, sep. 2013. ilus, tab
Article Dans Espagnol | LILACS | ID: lil-749967

Résumé

En la literatura científica mundial, existen muchos estudios que demuestran la capacidad antimicrobiana de diferentes hierbas, incluyendo el té verde. No obstante, muchos resultados son divergentes o no comparables. También, existen en el mercado muchas formulaciones de té verde, de las cuales hay poca información respecto a su actividad. En el presente trabajo se determinó el potencial efecto antimicrobiano contra cepas de Escherichia coli, Salmonella enterica, Listeria monocytogenes, Staphylococcus aureus, Candida albicans y Aspergillus niger de 50 muestras diferentes de té verde seco y en infusión al 10%, distribuidas de manera comercial en Costa Rica. Se contrastó su actividad con la del té verde (Camellia sinensis) de origen chino. Se evaluaron diferentes solventes para preparar extractos ricos en polifenoles a partir del té verde. Los fenoles totales se determinaron mediante el método espectrofotométrico de Folin-Ciocalteu usando el ácido gálico como material de referencia. La evaluación de la capacidad antimicrobiana del extracto y las infusiones de té verde se llevó a cabo mediante el método de microplatos descrito por Breukink (2006). El etanol fue el solvente que mostró mayor eficiencia. No hubo efecto antimicrobiano de las diferentes muestras contra los microorganismos evaluados, excepto con Listeria monocytogenes, dondese evidenció un efecto inhibitorio en las concentraciones de 10,5 y 1,05 mg/mL de los extractos en el 70% de marcas analizadas y en el control. Ninguna de las infusiones evaluadas, incluyendo la del té control mostró efecto inhibitorio contra esta bacteria.


Many studies can be found in scientific literature demonstrating the antimicrobial capacity of different herbs, including green tea. Nevertheless, many results are divergent or cannot be compared. Several green tea formulations may be found in market, but there is scarce or non-information about its activity. In this work, the potential antimicrobial effect of 50 samples of dry green tea and in 10% infusion against Escherichia coli, Salmonella enterica, Listeria monocytogenes, Staphylococcus aureus, Candida albicans and Aspergillus niger distributed in the metropolitan area of Costa Rica, was determined. This activity was compared with the effect produced by Chinese origin green tea (Camellia sinensis). Different solvents were evaluated for preparing polyphenol enriched extracts from green tea samples. Total phenols were determined using the Folin-Ciocalteu spectrophotometric methodology, using galic acid as reference. Antimicrobial activity of green tea extracts and infusions was evaluated using the microplate methodology described by Breuking (2006). Ethanol was the most efficient solvent used for the polyphenol extractions. There was no antimicrobial effect of the different green tea extracts and infusions against the microorganisms evaluated, except for Listeria monocytogenes, where the extracts of 70% of samples analyzed and the control showed an inhibitory effect in the 10,5 mg/mL and 1,05 mg/L concentrations. None of the infusions tested, including the control, showed any effect against this bacteria.


Sujets)
Antibactériens/pharmacologie , Camellia sinensis/composition chimique , Tests de sensibilité microbienne , Thé/composition chimique , Antibactériens/isolement et purification , Aspergillus niger/effets des médicaments et des substances chimiques , Costa Rica , Candida albicans/effets des médicaments et des substances chimiques , Escherichia coli/effets des médicaments et des substances chimiques , Listeria monocytogenes/effets des médicaments et des substances chimiques , Salmonella enterica/effets des médicaments et des substances chimiques , Staphylococcus aureus/effets des médicaments et des substances chimiques
19.
Pakistan Journal of Pharmaceutical Sciences. 2013; 26 (3): 511-516
Dans Anglais | IMEMR | ID: emr-142611

Résumé

Being rich in polyphenolic compounds such as flavonoids, green tea is suggested to be a potential candidate for the treatment of obesity, stress, depression, Parkinson's and other disorders. Since serotonin has an important role in the pathophysiology of these disorders, present study was designed to monitor the effects of green tea in rats. Green tea extract was provided to the male Albino Wistar rats for 5 weeks, and effects on behaviors were monitored. Results show a decrease in food intake after 5th week but not before. An increase in locomotive activities of the animals was observed, as monitored in novel as well as in familiar environment. Anxiolytic effects were observed in elevated plus maze but not in light dark activity box. An increase in dopamine and serotonin turnover was observed. Our results suggest that beneficial effects of green tea drinking might be due to alteration of serotonin and/or dopamine metabolism. We thereby propose that in further experiments, green tea should be administered in animal model of learned helplessness and effects on the development of adaptation to stress should be monitored. Neurochemical estimations of catecholamine and indoleamine in these animal models of stress exposed to green tea would help in understanding the anxiolytic effects of green tea


Sujets)
Mâle , Animaux de laboratoire , Apprentissage du labyrinthe/effets des médicaments et des substances chimiques , Activité motrice/effets des médicaments et des substances chimiques , Extraits de plantes/composition chimique , Sérotonine/métabolisme , Thé/composition chimique , Rat Wistar , Dopamine/métabolisme , Consommation alimentaire/effets des médicaments et des substances chimiques , Anxiolytiques/pharmacologie , Comportement animal/effets des médicaments et des substances chimiques
20.
Arch. latinoam. nutr ; 62(4): 389-390, dic. 2012. ilus, tab
Article Dans Espagnol | LILACS | ID: lil-714894

Résumé

Volatiles from aqueous extract of peppermint commercial sachets were investigated through gas chromatography/flame ionization detection (GC/FID) and GC/mass spectrometry (MS). Samples were prepared under similar conditions as in homemade tea. Volatiles were isolated using solid phase extraction method (SPE) with Porapak Q trap followed by desorption with acetone. Estimated mean values for short and medium chain carboxylic acids (C2- C12) and ketones lay in the range of 50-64 μg kg-1 whilst aliphatic alcohols and acyclic hydrocarbons had values lower than 6 μg kg-1. The major volatiles were terpenes (275-382 μg kg-1) that reached 89 % of the total composition. A total of 16 compounds, among them dodecane, acetoin, acetol, citral, geraniol and octanoic acid have been described by the first time in peppermint tea. These findings could be attributed to the different analytical approach employed, mainly to the use of different extraction/pre-concentration techniques. Given the apparently lower proportion of terpenes in the aqueous extract it may be that the chemical properties of the peppermint essential oil are not entirely reproduced with homemade tea.


Estudo da composição da fração volátil do extrato aquoso de sachês de hortelã pimenta (Mentha piperita L.) através da extração em fase sólida. O princípio desse trabalho foi investigar a fração volátil do extrato aquoso de sachês comerciais de hortelã pimenta usando cromatografia gasosa com detectores de ionização em chama e de massas. As amostras foram preparadas em condições similares às usadas para o preparo do chá caseiro. Os compostos voláteis foram isolados via método de extração em fase sólida com adsorvente Porapak Q e eluídos com acetona. Uma estimativa dos valores médios dos ácidos carboxílicos de cadeias média e curta ficou na faixa de 50-64 μg kg-1, enquanto alcoóis alifáticos e hidrocarbonetos acíclicos tiveram valores menores do que 6 μg kg-1. Os terpenos (275-382 μg kg-1) foram os compostos majoritários alcançando 89 % dos sólidos totais. Um total de 16 compostos voláteis, entre eles, dodecano, acetoína, acetol, citral, geraniol e ácido octanóico foram descritos pela primeira vez no chá de hortelã pimenta. Esses resultados poderiam ser atribuídos aos diferentes métodos analíticos empregados, principalmente devido ao uso de diferentes técnicas de extração e pré-concentração. Em função da proporção menor de terpenos no extrato aquoso é razoável especular que as propriedades químicas do óleo essencial da hortelã pimenta não sejam totalmente reproduzidas com o consumo do chá caseiro.


Sujets)
Mentha piperita/composition chimique , Huile essentielle/analyse , Extraits de plantes/analyse , Extraction en phase solide/normes , Thé/composition chimique , Composés organiques volatils/analyse , Acides carboxyliques/analyse , Ionisation de flamme , Chromatographie gazeuse-spectrométrie de masse , Cétones/analyse , Spectrométrie de masse/normes , Feuilles de plante/composition chimique , Terpènes/analyse
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