Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
2.
Metab Brain Dis ; 37(4): 1155-1161, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35275349

RESUMO

Maple Syrup Urine Disease (MSUD) is an autosomal recessive inherited disorder caused by a deficiency in the activity of the branched-chain alpha-ketoacid dehydrogenase complex leading to the accumulation of branched-chain amino acids (BCAA) leucine, isoleucine, and valine and their respective branched-chain α-ketoacids and corresponding hydroxy acids. Considering that Danio rerio, known as zebrafish, has been widely used as an experimental model in several research areas because it has favorable characteristics that complement other experimental models, this study aimed to evaluate oxidative stress parameters in zebrafish exposed to high levels of leucine (2 mM and 5 mM), in a model similar of MSUD. Twenty-four hours after exposure, the animals were euthanized, and the brain content dissected for analysis of oxidative stress parameters: thiobarbituric acid reactive substances (TBARS), 2',7'-dichlorofluorescein oxidation assay (DCF); content of sulfhydryl, and superoxide dismutase (SOD) and catalase (CAT) activities. Animals exposed to 2 mM and 5 mM leucine showed an increase in the measurement of TBARS and decreased sulfhydryl content. There were no significant changes in DCF oxidation. In addition, animals exposed to 2 mM and 5 mM leucine were found to have decreased SOD activity and increased CAT activity. Based on these results, exposure of zebrafish to high doses of leucine can act as a promising animal model for MSUD, providing a better understanding of the toxicity profile of leucine exposure and its use in future investigations and strategies related to the pathophysiology of MSUD.


Assuntos
Doença da Urina de Xarope de Bordo , Peixe-Zebra , Animais , Antioxidantes/farmacologia , Encéfalo/metabolismo , Leucina/metabolismo , Leucina/farmacologia , Doença da Urina de Xarope de Bordo/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Peixe-Zebra/metabolismo
4.
Metab Brain Dis ; 36(2): 247-254, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33098071

RESUMO

Maple Syrup Urine Disease (MSUD) is an autosomal recessive inherited disorder that affects the activity of the branched-chainα-keto acid dehydrogenase complex (BCDK). This deficiency on BCDK complex results in the accumulation of branched-chain amino acids (BCAA) leucine, isoleucine, valine, and their corresponding α-keto acids. Epigenetic changes can negatively affect the metabolism of BCAA. These changes are catalyzed by the epigenetic regulatory enzymes, e.g., DNA methyltransferase (DNMT), histone deacetylases (HDAC), and histone acetyltransferases (HAT). However, the impacts of BCAA administration on the activity of epigenetic regulatory enzymes in the brain of MSUD patients are still unknown. In this study, we aimed to demonstrate the impact of BCAA administration on the activity of DNMT, HDAC, and HAT in the brain structures of infant rats, an animal model of MSUD. For that, we administered a BCAA pool to infant rats for 21 days. We demonstrated that BCAA administration significantly increased the DNMT and HDAC activities in the hippocampus and striatum, but not in the cerebral cortex of MSUD infant rats. A positive correlation was observed between HDAC and DNMT activities in the hippocampus and striatum of animals exposed to BCAA injections. Our results showed that the BCAA administration could modulate epigenetic regulatory enzymes, mainly DNMT and HDAC, in the brains of infant rats. Therefore, we suggest that the increase in the activity of DNMT and HDAC in the hippocampus and striatum could partially explain the neurological impairments presented in animal models of MSUD.


Assuntos
Aminoácidos de Cadeia Ramificada/administração & dosagem , Córtex Cerebral/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Doença da Urina de Xarope de Bordo/metabolismo , Animais , Córtex Cerebral/metabolismo , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Masculino , Ratos , Ratos Wistar
5.
Hortic Res ; 7: 22, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32140231

RESUMO

Photooxidative stress, when combined with elevated temperatures, triggers various defense mechanisms leading to physiological, biochemical, and morphological changes in fruit tissue. Furthermore, during sun damage, apple fruit undergo textural changes characterized by high flesh firmness compared to unexposed fruit. Fuji and Royal Gala apples were suddenly exposed to sunlight on the tree and then sampled for up to 29 days. Cell wall components and lignin biosynthetic pathway analyses were carried out on the fruit tissue. At harvest, Fuji apples with different sun exposure levels, such as exposed to direct sunlight (Exp), shaded (Non-Exp), and with severe sun damage (Sev), were also characterized. In fruit suddenly exposed to sunlight, the expression levels of phenylpropanoid-related genes, phenylalanine ammonia lyase (MdPAL), chalcone synthase (MdCHS), and flavanone-3-hydroxylase (MdF3H), were upregulated in the skin and flesh of Exp and Sev. Exposure had little effect on the lignin-related genes caffeic acid O-methyltransferase 1 (MdCOMT1) and cinnamyl alcohol dehydrogenase (MdCAD) in the skin; however, the expression of these genes was highly induced in the flesh of Exp and Sev in both cultivars. Lignin deposition increased significantly in skin with sun injury (Sev); in flesh, this increase occurred late during the stress treatment. Additionally, the ethylene biosynthesis genes 1-aminocyclopropane-1-carboxylate synthase (MdACS) and 1-aminocyclopropane-1-carboxylate oxidase (MdACO) were highly expressed in the skin and flesh tissues but were more upregulated in Sev than in Exp during the time-course experiment, which paralleled the induction of the phenylpropanoid pathway and lignin accumulation. At harvest, flesh from Sev fruit exhibited higher firmness than that from Non-Exp and Exp fruit, although no differences were observed in the alcohol-insoluble residues (AIR) among groups. The fractionation of cell wall polymers revealed an increase in the uronic acid contents of the water-soluble pectin fraction (WSF) in Exp and Sev tissues compared to Non-Exp tissues, while the other pectin-rich fractions, that is, CDTA-soluble (CSF) and Na2CO3-soluble (NSF), were increased only in Sev. The amount of hemicellulose and cellulose did not differ among fruit conditions. These findings suggest that increases in the flesh firmness of apples can be promoted by photooxidative stress, which is associated with the induction of lignin accumulation in the skin and flesh of stressed fruit, with the involvement of stress phytohormones such as ethylene.

6.
J Sci Food Agric ; 99(5): 2556-2564, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30393859

RESUMO

BACKGROUND: Fruit and vegetable processing can often alter and damage antioxidants. Phenolic compounds, which are major antioxidants in these products, can suffer dissociation and changes in their concentration. Quince is an excellent source of antioxidants, with health-improving potential for consumers. The phenolic profile (by ultra-high-performance liquid chromatography-mass spectrometry) and quality attributes (pH, soluble solids, acidity, water activity) were determined for processed quince products (fresh fruit puree, cooked puree and dried bars), in addition to the effect of puree cooking time (5, 10, 15 and 20 min). RESULTS: Soluble solids in purees averaged 14.4 °Brix and increased to 75 °Brix in bars, as did titratable acidity, reaching 1.5 g malic acid kg-1 fresh weight after 20 min of cooking at 120 °C. Quercetin, p-coumaric acid and trans-cinnamic acid were predominant in fresh fruit puree. Thermal processing significantly increased the concentration of p-coumaric acid, trans-cinnamic acid, apigenin and quercetin, and decreased gallic acid. This increase was 242%, on average, for all of them when comparing fresh fruit puree with bars on a fresh weight basis, demonstrating their concentration throughout the dehydration process during bar production. CONCLUSION: Although a minimum puree cooking time of 5 min was sufficient to obtain the highest concentration of most phenolics, p-coumaric acid showed a higher concentration after 20 min of cooking. © 2018 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Fenóis/química , Rosaceae/química , Lanches , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Sementes/química
7.
Bol. latinoam. Caribe plantas med. aromát ; 17(1): 36-52, ene. 2018. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-915054

RESUMO

A comparative study of antioxidant properties, platelet antiaggregation activity and transcriptional analysis of flavonoid biosynthesis genes were performed in Fragaria x ananassa, F. vesca and F. chiloensis subsp chiloensis f. chiloensis and f. patagonica. Furthermore, differences in flavonoid content were found by UHPLC-MS. The highest free radical scavenging activity by DPPH assay was observed in F. chiloensis f. chiloensis, meanwhile, F. vesca presented the highest antioxidant capacity by FRAP. Biosynthetic flavonoids- related transcripts were higher abundant in F. x ananassa and lower in F. vesca. Additionally, all strawberry extracts showed antiaggregant effect (1 mg mL-1), but F. vesca and F. chiloensis subsp. chiloensis f. patagonica were still active at lower concentration. This study suggests that platelet antiaggregation effect of different strawberries could be due to isoflavones and flavonoids precursors in addition to anthocyanins. Results could usefully to take decisions in future breeding programs to improve the content of healthy compounds in strawberry fruits.


Se realizó un estudio comparativo de propiedades antioxidantes, actividad de antiagregacion plaquetaria, análisis transcripcional de genes de biosíntesis de flavonoides y contenido de estos en Fragaria x ananassa, F. vesca and F. chiloensis subsp chiloensis f. chiloensis and f. patagonica. La mayor actividad removedora de radicales libres por DPPH se observó en F. chiloensis f. chiloensis, mientras F. vesca presentó la mayor capacidad antioxidante mediante FRAP. Transcritos relacionados con biosíntesis de flavonoides fueron mas abundantes en F. x ananassa y menores en F. vesca. Adicionalmente, todos los extractos de frutillas mostraron efectos antiagregante (1 mg mL-1), pero F. vesca and F. chiloensis subsp. chiloensis f. patagonica fueron activos a concentraciones menores. Este estudio sugiere que efectos de antiagregación plaquetaria en distintas frutillas podría deberse a isoflavonas y precursores de flavonoides además de antocianinas. Los resultados podrían ser útiles en programas de mejoramiento genético para mejorar el contenido de compuestos saludables en frutilla.


Assuntos
Extratos Vegetais/química , Fragaria/química , Antioxidantes/química , Flavonoides/análise , Flavonoides/genética , Flavonoides/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Extratos Vegetais/farmacologia , Expressão Gênica , Sequestradores de Radicais Livres , Cromatografia Líquida de Alta Pressão/métodos , Recuperação de Fluorescência Após Fotodegradação , Reação em Cadeia da Polimerase em Tempo Real , Antioxidantes/farmacologia
8.
Rev. peru. med. exp. salud publica ; 34(4): 660-665, oct.-dic. 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-902959

RESUMO

RESUMEN El tratamiento empírico para la infección urinaria se ve complicado frente a la presencia de multirresistencia y de betalactamasas de espectro extendido (BLEE). El objetivo del estudio fue describir los patrones de resistencia antibiótica de cepas de Escherichia coli aisladas en urocultivos y los factores clínico-epidemiológicos asociados a la presencia de BLEE en un grupo pediátrico y adulto. Se recolectaron durante 14 meses, 353 cepas provenientes de Emergencia y Hospitalización del Hospital Cayetano Heredia, 45,9% fueron cepas multirresistentes. La incidencia de BLEE en población pediátrica fue 16,3% vs. 31,1% en la adulta, el 63,6% provenía de pacientes ambulatorios. La presencia de BLEE se asoció con encontrarse hospitalizado en pediatría, así cómo al uso de pañal y vejiga neurogénica en adultos. Estos factores deben considerarse al momento de elegir un tratamiento antibiótico. Asimismo, es necesario implementar programas de reporte epidemiológico y modelos de prevención de factores de riesgo.


ABSTRACT The empirical treatment of urinary infections is complicated by the presence of multiresistance and resistance to extendedspectrum beta-lactamases (ESBLs). The objective of this study was to describe the patterns of antibiotic resistance of Escherichia coli strains isolated from urine cultures and the clinical-epidemiological factors associated with the presence of ESBLs in a pediatric and an adult group. A total of 353 strains were collected from the Emergency and Hospitalization Sector of the Cayetano Heredia Hospital over 14 months, and 45.9% of the isolated strains were multiresistant. The rate of resistance to ESBLs in the pediatric and adult population was 16.3% and 31.1%, respectively, and 63.6% of the resistant strains were isolated from outpatients. The presence of ESBLs was associated with hospitalization in pediatrics, use of diapers, and the presence of neurogenic bladder in adults. These factors should be considered in selection of an antibiotic treatment. Moreover, epidemiological reporting programs and models should be implemented for reduction of risk factors.


Assuntos
Adulto , Feminino , Humanos , Masculino , Infecções Urinárias/microbiologia , Infecções Urinárias/tratamento farmacológico , beta-Lactamases/fisiologia , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Urina/microbiologia , Estudos Transversais , Escherichia coli/isolamento & purificação
9.
Front Plant Sci ; 8: 2129, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29491868

RESUMO

Sun-related physiological disorders such as sun damage on apples (Malus domestica Borkh) are caused by cumulative photooxidative and heat stress during their growing season triggering morphological, physiological, and biochemical changes in fruit tissues not only while it is on the tree but also after it has been harvested. The objective of the work was to establish the interaction of auxin (indole-3-acetic acid; IAA), abscisic acid (ABA), jasmonic acid (JA), salicylic acid (SA), and ethylene (ET) and its precursor ACC (free and conjugated, MACC) during development of sun-injury-related disorders pre- and post-harvest on apples. Peel tissue was extracted from fruit growing under different sun exposures (Non-exposed, NE; Exposed, EX) and with sun injury symptoms (Moderate, Mod). Sampling was carried out every 15 days from 75 days after full bloom (DAFB) until 120 days post-harvest in cold storage (1°C, > 90%RH). Concentrations of IAA, ABA, JA, SA, were determined using UHPLC mass spectrometry, and ET and ACC (free and conjugated MACC) using gas chromatography. IAA was found not to be related directly to sun injury development, but it decreased 60% in sun exposed tissue, and during fruit development. ABA, JA, SA, and ethylene concentrations were significantly higher (P ≤ 0.05) in Mod tissue, but their concentration, except for ethylene, were not affected by sun exposure. ACC and MACC concentrations increased until 105 DAFB in all sun exposure categories. During post-harvest, ethylene climacteric peak was delayed on EX compared to Mod. ABA and SA concentrations remained stable throughout storage in both tissue. JA dramatically increased post-harvest in both EX and Mod tissue, and orchards, confirming its role in low temperature tolerance. The results suggest that ABA, JA, and SA together with ethylene are modulating some of the abiotic stress defense responses on sun-exposed fruit during photooxidative and heat stress on the tree.

10.
Rev Peru Med Exp Salud Publica ; 34(4): 660-665, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-29364420

RESUMO

The empirical treatment of urinary infections is complicated by the presence of multiresistance and resistance to extendedspectrum beta-lactamases (ESBLs). The objective of this study was to describe the patterns of antibiotic resistance of Escherichia coli strains isolated from urine cultures and the clinical-epidemiological factors associated with the presence of ESBLs in a pediatric and an adult group. A total of 353 strains were collected from the Emergency and Hospitalization Sector of the Cayetano Heredia Hospital over 14 months, and 45.9% of the isolated strains were multiresistant. The rate of resistance to ESBLs in the pediatric and adult population was 16.3% and 31.1%, respectively, and 63.6% of the resistant strains were isolated from outpatients. The presence of ESBLs was associated with hospitalization in pediatrics, use of diapers, and the presence of neurogenic bladder in adults. These factors should be considered in selection of an antibiotic treatment. Moreover, epidemiological reporting programs and models should be implemented for reduction of risk factors.


El tratamiento empírico para la infección urinaria se ve complicado frente a la presencia de multirresistencia y de betalactamasas de espectro extendido (BLEE). El objetivo del estudio fue describir los patrones de resistencia antibiótica de cepas de Escherichia coli aisladas en urocultivos y los factores clínico-epidemiológicos asociados a la presencia de BLEE en un grupo pediátrico y adulto. Se recolectaron durante 14 meses, 353 cepas provenientes de Emergencia y Hospitalización del Hospital Cayetano Heredia, 45,9% fueron cepas multirresistentes. La incidencia de BLEE en población pediátrica fue 16,3% vs. 31,1% en la adulta, el 63,6% provenía de pacientes ambulatorios. La presencia de BLEE se asoció con encontrarse hospitalizado en pediatría, así cómo al uso de pañal y vejiga neurogénica en adultos. Estos factores deben considerarse al momento de elegir un tratamiento antibiótico. Asimismo, es necesario implementar programas de reporte epidemiológico y modelos de prevención de factores de riesgo.


Assuntos
Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia , beta-Lactamases/fisiologia , Adulto , Estudos Transversais , Escherichia coli/isolamento & purificação , Feminino , Humanos , Masculino , Urina/microbiologia
11.
Genome Announc ; 4(5)2016 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-27738043

RESUMO

Avian coronavirus is the causative agent of infectious bronchitis in chickens, leading to multisystemic disease that might be controlled if adequate vaccine strains are used. This paper reports the first complete genome sequence of a Brazil type of this virus (27,615 nucleotides [nt]) isolated from the kidneys of a chicken.

12.
J Food Sci ; 81(3): C569-77, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26799705

RESUMO

Strawberry and kiwi leathers were used to develop a new healthy and preservative-free fruit snack for new markets. Fruit puree was dehydrated at 60 °C for 20 h and subjected to accelerated storage. Soluble solids, titratable acidity, pH, water activity (aw ), total phenolic (TP), antioxidant activity (AOA) and capacity (ORAC), and color change (browning index) were measured in leathers, cooked, and fresh purees. An untrained panel was used to evaluate consumer acceptability. Soluble solids of fresh purees were 11.24 to 13.04 °Brix, whereas pH was 3.46 to 3.39. Leathers presented an aw of 0.59 to 0.67, and a moisture content of 21 kg water/100 kg. BI decreased in both leathers over accelerated storage period. TP and AOA were higher (P ≤ 0.05) in strawberry formulations. ORAC decreased 57% in strawberry and 65% in kiwi leathers when compared to fruit puree. TP and AOA increased in strawberries during storage. Strawberry and Kiwi leathers may be a feasible new, natural, high antioxidant, and healthy snack for the Chilean and other world markets, such as Europe, particularly the strawberry leather, which was preferred by untrained panelists.


Assuntos
Actinidia/química , Antioxidantes/farmacologia , Análise de Alimentos , Armazenamento de Alimentos , Fragaria/química , Frutas/química , Fenóis/farmacologia , Animais , Antioxidantes/análise , Chile , Cor , Dessecação , Dieta , Europa (Continente) , Humanos , Concentração de Íons de Hidrogênio , Fenóis/análise , Extratos Vegetais/farmacologia , Lanches , Temperatura , Água
13.
Arch. venez. pueric. pediatr ; 74(1): 16-22, mar. 2011. tab
Artigo em Espanhol | LILACS | ID: lil-659165

RESUMO

Las parasitosis intestinales son aún un problema de salud pública que requiere atención de los organismos la salud. Determinar la frecuencia de parasitosis intestinales y características epidemiológicas en niños de 1 a 12 años que acudieron al Ambulatorio Urbano Tipo II “Laura Labellarte”. Se realizó un estudio descriptivo de corte transversal, con muestra no probabilística por conveniencia, constituida por 139 niños. Previo consentimiento informado se realizó una entrevista, un examen de heces directo y concentrado y método de Graham. Los datos se procesaron en el Programa EPI-INFO 2007. Se calcularon porcentajes y proporciones, Chi cuadrado y test de Fisher con intervalo de confianza de 95%. Se encontró parasitado 49,6%, sin predilección por edad ni sexo. Se identificó Blastocystis hominis (43,5%), Enterobius vermicularis (39,1%), Giardia lamblia (33,3%), Entamoeba histolytica (10,1%) y Ascaris lumbricoides (1,4%). Se encontró comensales en 15%. El mayor número de parasitados se observó en quienes tenían inadecuadas disposición de excretas (71%), conservación de los alimentos (57,1%), calidad del agua de consumo (53,8%) y frecuencia de recolección de basura (50%), así como en los sintomáticos (51,3%), siendo más frecuente el dolor abdominal (66,7%). Se demostró asociación de vectores con Blastocystis hominis, moscas con Giardia lamblia y roedores con todos los agentes hallados. La elevada frecuencia de parasitos intestinales, especialmente Blastocystis hominis, con predominio entre quienes viven con fallas en la disposición de excretas, conservación de alimentos y la calidad del agua para consumo, demuestran la persistencia de las parasitosis intestinales como problema de salud pública


The intestinal parasitisms are still a problem of public health that requires attention of health organisms. To determine the frequency of intestinal parasitism and epidemiological characteristics in children 1 to 12 years old that attended the “Laura Labellarte” Urban Type II Ambulatory. A cross-sectional descriptive study was performed, with a nonprobabilistic by convenience sample, constituted by 139 children. With a previous informed consent, parents were interviewed and a direct and concentrate fecal analysis and a Graham´s test were performed. The data was processed in EPI-INFO 2007 Program. Percentage, proportions, Chi square and Fisher`s test with confidence interval of 95% were calculated. 49,6% of patients were parasited, with no predilection by age or sex. Blastocystis hominis (43,5%), Enterobius vermicularis (39,1%), Giardia lamblia (33,3%), Entamoeba histolytica (10,1%) and Ascaris lumbricoides (1,4%) were identified. The greater number of parasited patients was observed in those who had inadequate disposition of feces (71%), food storage (57,1%), quality of drinking water (53,8%) and garbage collection (50%) as well as in symptomatic children (51,3%). The most frequent symptom was abdominal pain (66,7%). Association of vectors with Blastocystis hominis, flies with Giardia lamblia and rodents with all causal agents was demonstrated. The high intestinal parasitisms frequency, especially Blastocystis hominis, with predominance among those who live with faults in feces disposition, foods storage and quality of drinking water, demonstrates the persistence of intestinal parasitisms as a public health problem


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Blastocystis , Meio Ambiente , Insetos Vetores , Enteropatias Parasitárias/epidemiologia , Higiene , Saúde Pública
14.
J Psychiatr Res ; 45(2): 220-4, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20576277

RESUMO

The disruption of glycogen synthase kinase 3-beta (GSK3B) homeostasis has implications in the pathophysiology of neuropsychiatric disorders, namely Alzheimer's disease (AD). GSK3B activity is increased within the AD brain, favoring the hyperphosphorylation of microtubule-associated protein Tau and the formation of neurofibrillary tangles. Such abnormality has also been detected in leukocytes of patients with cognitive disorders. The aim of the present study was to determine the expression of total and phosphorylated GSK3B at protein level in platelets of older adults with varying degrees of cognitive impairment, and to compare GSK3B activity in patients with AD, mild cognitive impairment (MCI) and healthy controls. Sixty-nine older adults were included (24 patients with mild to moderate AD, 22 patients with amnestic MCI and 23 elderly controls). The expression of platelet GSK3B (total- and Ser-9 phosphorylated GSK3B) was determined by Western blot. GSK3B activity was indirectly assessed by means of the proportion between phospho-GSK3B to total GSK3B (GSK3B ratio), the former representing the inactive form of the enzyme. Ser-9 phosphorylated GSK3B was significantly reduced in patients with MCI and AD as compared to controls (p=0.04). Platelet GSK3B ratio was significantly decreased in patients with MCI and AD (p=0.04), and positively correlated with scores on memory tests (r=0.298, p=0.01). In conclusion, we corroborate previous evidence of increased GSK activity in peripheral tissues of patients with MCI and AD, and further propose that platelet GSK may be an alternative peripheral biomarker of this abnormality, provided samples are adequately handled in order to preclude platelet activation.


Assuntos
Doença de Alzheimer/sangue , Plaquetas/enzimologia , Transtornos Cognitivos/sangue , Quinase 3 da Glicogênio Sintase/sangue , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Glicogênio Sintase Quinase 3 beta , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Serina/metabolismo
15.
J Exp Bot ; 57(9): 1933-47, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16698820

RESUMO

Photo-oxidative stress was imposed under natural solar radiation on exposed and shaded sections of detached fruit of immature green tomato (Lycopersicon esculentum Miller = Solanum lycopersicum L.) mutants (anthocyanin absent, beta-carotene, Delta, and high pigment-1) and their nearly isogenic parents ('Ailsa Craig' and 'Rutgers'). After 5 h exposure to high solar irradiance, either with or without ultraviolet (UV) radiation, surface colour changes, pigment composition, photosynthetic efficiency, antioxidant metabolites and enzyme activities, and selected flavonoids and antioxidant proteins in exocarp tissue were evaluated. The imposed photo-oxidative stress reproduced the symptoms observed on attached fruit. Both high temperature and solar irradiance caused fruit surface discoloration with faster degradation of chlorophyll (Chl) than carotenoids (Car), leading to an increase in the Car/Chl ratio. Surface bleaching was mostly caused by visible light, whereas elevated temperatures were mostly responsible for the inactivation of photosynthesis, measured as decreased F(v)/F(m). Ascorbate, glutathione, and total soluble protein concentrations decreased in the exocarp as the duration of exposure increased. Specific activities of superoxide dismutase, ascorbate peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase (MDHAR), glutathione reductase (GR), and catalase increased with exposure, suggesting that these proteins were conserved during the imposed stress. GR protein expression remained stable during the imposed stress, whereas, MDHAR protein expression increased. Quercetin and kaempferol concentrations increased rapidly upon exposure, but not to UV radiation, suggesting rapid photo-protection in response to visible light; however, naringenin synthesis was not induced. The apparent increased tolerance of hp-1 fruit is discussed.


Assuntos
Frutas/efeitos da radiação , Solanum lycopersicum/efeitos da radiação , Luz Solar , Aclimatação , Antioxidantes/metabolismo , Antioxidantes/efeitos da radiação , Meio Ambiente , Flavonoides/metabolismo , Flavonoides/efeitos da radiação , Frutas/genética , Frutas/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Mutação , Fotossíntese/efeitos da radiação , Pigmentação/efeitos da radiação
16.
J Agric Food Chem ; 53(24): 9536-43, 2005 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-16302774

RESUMO

Flavonoids have been studied extensively because they offer great potential health benefits. In this study, enzymatic hydrolysis of glycosylated quercetin, kaempferol, and naringin was used to obtain their sugar-free aglycones. The investigation also employed a validated HPLC method to obtain the chiral disposition of the aglycone naringenin enantiomers. These analyses were conducted on exocarp, mesocarp, and seed cavity tissues of field-grown tomato (Lycopersicon esculentum Mill.) mutants (anthocyanin absent, atroviolacea, and high pigment-1) and their nearly isogenic parent (cv. Ailsa Craig) at immature green, "breaker", and red ripe maturity stages. Concentrations of all flavonoids using enzymatic hydrolysis were significantly higher than previously reported concentrations using acid hydrolysis. Presumably, this occurred due to a more specific and rapid hydrolysis of the glycoside moiety by the beta-glucosidase enzyme. The glycoside S-naringin was the predominant enantiomer in all fruit tissues, although the aglycones free R- and S-naringenin were detected in both exocarp and mesocarp. Whereas there was significantly more quercetin than kaempferol in exocarp tissue, they were present in about equal concentrations in the mesocarp. Quercetin concentrations were higher in the exocarp and mesocarp of immature green and breaker fruit of the high pigment-1 mutant than in the other genotypes, supporting the observed photoprotection and potential health benefits of the high pigment-1 tomato genotype.


Assuntos
Flavonoides/análise , Frutas/química , Genótipo , Solanum lycopersicum/química , Solanum lycopersicum/genética , Enzimas , Flavanonas/análise , Concentração de Íons de Hidrogênio , Hidrólise , Quempferóis/análise , Mutação , Quercetina/análise , beta-Glucosidase/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA