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1.
J Food Biochem ; 46(12): e14458, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36265159

RESUMEN

The phenolics are the main bioactive substances of Huangshan Gongju, a famous chrysanthemum of China, but their digestive characteristics are still unknown. To explore the digestive properties of Huangshan Gongju phenolics, the flower was extracted and subjected to simulated digestions, and their phenolic profile and activity were analyzed. The results indicated that the total phenolics content and antioxidant activity of the extract varied with the simulated digestion steps, and they generally decreased in the oral and small intestine digestions but increased in the gastric digestion, and high correlations were detected between the total phenolics content and antioxidant activity (0.873 < r < 0.979, p < .01). The change of phenolic profile during the simulated digestions was similar to that of total phenolics content, and six individual phenolics were identified and quantified, and three of them, including chlorogenic acid, apigenin-7-O-rutinoside, and apigenin-7-O-6″-acetylglucoside showed higher recovery (>64.29%), implying they may be the main functional phenolics of Huangshan Gongju. PRACTICAL APPLICATIONS: This study proved that most phenolics in Huangshan Gongju were relatively stable during digestion. The finding may guarantee the application of Huangshan Gongju in the field of functional foods.


Asunto(s)
Antioxidantes , Chrysanthemum , Fenoles , Extractos Vegetales , Digestión
2.
Cell Metab ; 34(3): 396-407.e6, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35235774

RESUMEN

We conducted a double-blinded phase I clinical trial to establish whether nicotinamide adenine dinucleotide (NAD) replenishment therapy, via oral intake of nicotinamide riboside (NR), is safe, augments cerebral NAD levels, and impacts cerebral metabolism in Parkinson's disease (PD). Thirty newly diagnosed, treatment-naive patients received 1,000 mg NR or placebo for 30 days. NR treatment was well tolerated and led to a significant, but variable, increase in cerebral NAD levels-measured by 31phosphorous magnetic resonance spectroscopy-and related metabolites in the cerebrospinal fluid. NR recipients showing increased brain NAD levels exhibited altered cerebral metabolism, measured by 18fluoro-deoxyglucose positron emission tomography, and this was associated with mild clinical improvement. NR augmented the NAD metabolome and induced transcriptional upregulation of processes related to mitochondrial, lysosomal, and proteasomal function in blood cells and/or skeletal muscle. Furthermore, NR decreased the levels of inflammatory cytokines in serum and cerebrospinal fluid. Our findings nominate NR as a potential neuroprotective therapy for PD, warranting further investigation in larger trials.


Asunto(s)
NAD , Enfermedad de Parkinson , Suplementos Dietéticos , Humanos , NAD/metabolismo , Niacinamida/análogos & derivados , Niacinamida/farmacología , Niacinamida/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Compuestos de Piridinio/uso terapéutico
3.
Food Chem ; 360: 130017, 2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-33984566

RESUMEN

With an aim to prepare the functional chocolate, corn oil was used as the base oil and ß-sitosterol was combined with oryzanol/stearic acid/lecithin to prepare respective oleogels (GO, SO, and LO). Oleogels (12%) were prepared by adding compound oleogelators at different ratios [GO-2:3, SO-1:4, and LO-4:1 (w/w)] in corn oil. The microstructure, interaction, thermodynamic, crystalline, and rheological behavior of formulated oleogels were studied by microscopic observation, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and rotational rheometer, respectively. The results showed that GO had the strongest gel forming ability and the densest gel crystallization network. Moreover, chocolate prepared with GO (cocoa butter and oleogels-1:1) had the similar texture, crystal structure, rheological, and sensory properties to that of dark chocolate. This study provides the possibility for the wider application of oleogel prepared with lower saturated and trans-fatty acids in the chocolate industry.


Asunto(s)
Chocolate , Lecitinas/química , Ácidos Esteáricos/química , Rastreo Diferencial de Calorimetría , Cristalización , Compuestos Orgánicos/química , Reología , Difracción de Rayos X
4.
Food Chem Toxicol ; 147: 111875, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33227389

RESUMEN

Huangshan Gongju was extracted with organic solvents (ethanol, methanol and acetone) of different concentrations (0-90%), and the extracts' phenolic content and antioxidant activity, as well as the correlations between them were examined. With the increasing concentration of organic solvent, the total phenolic compound (TPC) increased continuously and met its maximum at 70% acetone, whereas the total flavonoid compound (TFC) and most individual phenolics met their maximums at 70% ethanol. Similar changes occurred to the antioxidant activity, including DPPH and ABTS scavenging activities, and their maximums were respectively found at 50% acetone and 70% ethanol. The antioxidant activity correlated strongly with TPC/TFC (r > 0.954, p < 0.01) and individual phenolics (r > 0.886, p < 0.05), and the strongest correlations between them were mainly given by luteolin-7-O-glucoside (r > 0.975, p < 0.001). These results suggested that high content organic solvent (50-70%) was beneficial to obtain Huangshan Gongju extracts of higher phenolic content and antioxidant activity, and 70% ethanol may be the promising solvent. Besides, phenolics were found to be the main antioxidants of Huangshan Gongju extracts, and flavonoids especially luteolin-7-O-glucoside may play more important roles in the antioxidant activity.


Asunto(s)
Antioxidantes/farmacología , Asteraceae/química , Fenoles/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antioxidantes/química , Solventes/química
5.
Food Chem Toxicol ; 135: 110941, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31697970

RESUMEN

Bamboo leaves soups were subjected to in vitro digestion (including separated oral, gastric and small intestinal digestions, and complete digestion containing above three stages), and their phenolics and antioxidant activities were determined. Compared to control groups, total phenolic content (TPC) in treated groups (including undigested and digested groups) increased at gastric digestion stage but decreased at other digestion stages, and the decrease in small intestinal digestion stage (19.97%) was nearly the same with that in complete digestion stage (19.39%). The antioxidant activity in digested groups almost changed accordingly to their TPC but with no significant difference (p > 0.05) as compared with undigested groups; similar results were found in four main individual phenolics including cryptochlorogenic acid, chlorogenic acid, neochlorogenic acid and isoorientin, and their contents were negatively correlated to the pH value of digestion buffers (-0.68 < r < -0.80, p < 0.01). These results indicated that the change of phenolic content and antioxidant activity in digested bamboo leaves soups mainly resulted from the pH of digestion buffers rather than digestive enzymes. In addition, the decrease of phenolics may mainly occur at small intestinal digestion stage where the pH value is the highest in the digestive system.


Asunto(s)
Digestión , Depuradores de Radicales Libres/química , Fenoles/química , Extractos Vegetales/química , Hojas de la Planta/química , Poaceae/química , Depuradores de Radicales Libres/análisis , Fenoles/análisis , Extractos Vegetales/análisis
6.
Heliyon ; 5(12): e02853, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31872106

RESUMEN

The fruits of Gardenia jasminoides Ellis are folk medicines in China and their major components are geniposide and water soluble pigment crocins. This study compared the chemical profiles and free radical scavenging activities of two Zhizi species from five provinces of China, including Jiangxi, Anhui, Hunan, Sichuan and Henan. The results showed that Jiangxi Zhizi contained higher levels of volatiles (71.84%), crocins (20.38 mg/g), geniposide (31.36 mg/g) and flavonoids (84.42 µg quercetin/mg) than four other Zhizi fruits; whereas Hunan Zhizi provided higher total phenolics (33.81 µg catechin/mg) and ABTS/DPPH radical scavenging activities. These findings implied that Jiangxi Zhizi would be suitable for extraction of gardenia yellow and geniposide, as well as preparation of essential oil. This information may provide valuable guidance for application of Zhizi fruits to biomedicine industry in China.

7.
Food Chem Toxicol ; 119: 375-379, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29425934

RESUMEN

Phenolic acids and flavonoids in bamboo leaves are of great importance for their functional attributes, but they can hardly be separated simultaneously. In this study, zirconia was prepared and applied as a potential absorbent for simultaneous separation of these phenolic compounds. Three phenolic acids (neochlorogenic acid, chlorogenic acid and cryptochlorogenic acid) and two flavonoids (isoorientin and orientin) were isolated at the same time. The influence of bamboo leaves extraction conditions, zirconia calcination temperatures, desorption conditions and absorption/desorption dynamics on the separation were further investigated. When zirconia-400 (calcined at 400 °C) was treated with 70% ethanol extract of bamboo leaves for 40 min followed by desorption with 70% acetic acid solution for 60 min, the recovery of three chlorogenic acids and two flavonoids was about 65%. To conclude, the concise method developed here may provide a new way for simultaneous separation of phenolic acids and flavonoids from various plants.


Asunto(s)
Bambusa/química , Ácido Clorogénico/química , Ácido Clorogénico/aislamiento & purificación , Flavonoides/aislamiento & purificación , Extractos Vegetales/química , Hojas de la Planta/química , Circonio/química , Cromatografía Líquida de Alta Presión , Hidroxibenzoatos/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray
8.
J Food Drug Anal ; 26(1): 100-106, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29389544

RESUMEN

Zirconium phosphate (ZrP) was prepared and employed to separate strictinin-rich tea polyphenol from Chinese green tea extracts. The influences of ZrP calcination temperatures, green tea extraction conditions, and the amounts of ZrP on the isolation of strictinin-rich tea polyphenol were evaluated; the absorption and desorption dynamics of strictinin on ZrP were also determined. Our results revealed that the HPLC content of strictinin increased from 4.96% in 70% ethanol extract of green tea to 58.2% in isolated strictinin-rich tea polyphenol obtained by ZrP-900 (ZrP calcined at 900°C). Furthermore, the suitable time for both strictinin absorption and desorption was 4 hours at 37°C. The method developed here consisted of easy steps such as ZrP absorption, water washing, and 0.4% phosphoric acid solution desorption, which may facilitate the detection and isolation of strictinin from different samples.


Asunto(s)
Fenoles/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Polifenoles/química , Polifenoles/aislamiento & purificación , Té/química , Circonio , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Espectrometría de Masas , Estructura Molecular , Circonio/química
9.
Int J Biol Macromol ; 112: 22-32, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29374565

RESUMEN

In this work we described the rheological properties of polysaccharides (HBSS, CHSS, DASS, CASS) sequentially extracted from onion (Allium cepa L.). Four onion polysaccharides (ACLPs) solutions resulted into significant differences on their rheological properties. ACLPs solutions showed non-Newtonian shear-thinning behavior over the range of 0.5-2.5%. At concentration of 1%, the apparent viscosity of CHSS was observed to be the highest. The apparent viscosity of ACLPs solutions decreased with the acidic pH (4.0) or alkaline pH (10.0) which was further declined at higher temperature (90 °C). After the addition of various salts, ACLPs had apparent differences on apparent viscosity. The G' (storage modulus) and G″ (loss modulus) of ACLP solutions were increased with increasing oscillation frequency. Moreover, the crossover value of oscillation frequency gradually decreased with increasing concentration of ACLPs. Our results exhibited that among the ACLPs, CHSS can be used as supplements in the food industry as thickening agent, gelling agent and stabilizer.


Asunto(s)
Cebollas/química , Polisacáridos/aislamiento & purificación , Reología , Industria de Alimentos , Concentración de Iones de Hidrógeno , Polisacáridos/química , Temperatura , Viscosidad
10.
Int J Biol Macromol ; 111: 92-101, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29305215

RESUMEN

We investigated the antioxidant and antimicrobial potential of sequentially extracted onion polysaccharide fractions namely HBSS, CHSS, DASS and CASS. The different antioxidant assays indicated that ACLPs exhibited potentially appreciable antioxidant activity in a dose-dependent manner. Among all the fractions, CHSS rendered the highest antioxidant action towards ABTS radical cations (97.52%), Fe2+ chelating (98.94%) and superoxide anion radical scavenging (76.27%). Whereas, HBSS possessed the highest potential for DPPH radicals (93.68%), hydroxyl radicals (65.12%) as well as for reducing power (0.559). CASS exhibited the highest lipid peroxidation inhibition (86.43%), while, DASS showed the best ß-carotene bleaching inhibition (92.26%). Furthermore, regardless of the bacterial strain, DASS represented the strongest antibacterial activity on the basis of largest inhibition zone, the lowest minimal inhibitory concentration and maximum inhibition of bacterial growth in liquid medium. Overall results indicated that ACLPs hold a promise as potential natural antioxidant additives and antimicrobial agents for formulating the functional foods with potential applications in the medical and food industries.


Asunto(s)
Antibacterianos/química , Antioxidantes/química , Cebollas/química , Polisacáridos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/farmacología , Polisacáridos/aislamiento & purificación
11.
Int J Biol Macromol ; 105(Pt 1): 1192-1201, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28757419

RESUMEN

Onion polysaccharides (ACLP) were sequentially extracted with four different solvents (hot buffer, chelating agent, dilute alkaline and concentrated alkaline) and obtained four fractions, named as HBSS, CHSS, DASS and CASS, respectively. The present studies characterized the ACLP concerning its physicochemical and functional properties. Monosaccharides analysis revealed that mannose (81.68%) was the dominant sugar in HBSS and galactose (67.59%) was the most in CASS. Similarly, CHSS and DASS possessed mannose and galactose as major sugar, which were 25.80% and 31.37%, 20.33% and 33.96%, respectively. The obtained molecular weight of ACLPs were 7.702×103 (HBSS), 4.690×103 (CHSS), 4.943×103 (DASS) and 1.390×103kDa (CASS). CASS resulted in the strongest solubility, fat-binding capacity, foam capacity and foam stability whereas, HBSS showed the highest thermal stability. DASS showed the best hygroscopicity and the best moisture retention was obtained by CHSS. Subsequently, the emulsifying activity and emulsifying stability were the highest for HBSS and the longest for of CASS, respectively. The rheological properties of CHSS exhibited the largest viscosity. Our results indicated that all factions could be considered as functional polysaccharides according to their respective characteristics, which have vast potential in food production.


Asunto(s)
Fenómenos Químicos , Cebollas/química , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Manipulación de Alimentos , Calidad de los Alimentos , Peso Molecular , Monosacáridos/análisis , Reología , Factores de Tiempo
12.
Phytochem Anal ; 27(3-4): 153-7, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27313152

RESUMEN

INTRODUCTION: 5-O-Galloylquinic acid from green tea and other plants is attracting increasing attention for its antioxidant and antileishmanial bioactivities. It is always isolated using a silica column, a Sephadex column and high-performance liquid chromatography (HPLC) methods, which are either laborious or instrument dependent. OBJECTIVE: To develop a new method to easily separate 5-O-galloylquinic acid. METHODOLOGY: Mesoporous zirconium phosphate (m-ZrP) was prepared to conveniently separate 5-O-galloylquinic acid from Chinese green tea extract, and the target compound was easily obtained by simple steps of adsorption, washing and desorption. The effects of the green tea extraction conditions, extract concentrations, and m-ZrP adsorption/desorption dynamics on the 5-O-galloylquinic acid separation were evaluated. RESULTS: 5-O-Galloylquinic acid that was separated from a 70% ethanol extract of green tea was of moderate HPLC purity (92%) and recovery (88%), and an increased non-specific binding of epigallocatechin gallate (EGCG) on m-ZrP was observed in the diluted tea extract. The times for maximal adsorption of 5-O-galloylquinic acid in 70% ethanol extract and maximal desorption of 5-O-galloylquinic acid in 0.4% phosphoric acid solution were confirmed as 7 h and 5 h, respectively. CONCLUSION: A facile method to separate 5-O-galloylquinic acid from Chinese green tea extract using m-ZrP was established. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Antioxidantes/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Ácido Quínico/aislamiento & purificación , Té/química , Circonio/química , Adsorción , Antioxidantes/química , Catequina/análogos & derivados , Catequina/química , Catequina/aislamiento & purificación , Fraccionamiento Químico , Estructura Molecular , Extractos Vegetales/química , Ácido Quínico/química
13.
Int J Cancer ; 139(4): 928-37, 2016 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-27038145

RESUMEN

The purpose of our study was to test the hypothesis that sorafenib-related dermatologic adverse events (AEs) as an early biomarker can predict the long-term outcomes following the combination therapy of transarterial chemoembolization (TACE) plus sorafenib (TACE-S). The intermediate-stage hepatocellular carcinoma patients who received either TACE-S or TACE-alone treatment were consecutively included into analysis. In the TACE-S group, patients with ≥ grade 2 dermatologic AEs within the first month of sorafenib initiation were defined as responders; whereas those with < grade 2 were defined as nonresponders. In the TACE-S group, the median overall survival (OS) of the responders was significantly longer than that of nonresponders (28.9 months vs. 16.8 months, respectively; p = 0.004). Multivariate analysis demonstrated that nonresponders were significantly associated with an increased risk of death compared with responders (HR = 1.9; 95% confidence Interval-CI: 1.3-2.7; p = 0.001). The survival analysis showed that the median OS was 27.9 months (95% CI: 25.0-30.8) among responders treated with TACE-S vs.18.3 months (95% CI: 14.5-22.1) among those who received TACE-alone (p = 0.046). The median time to progression was 13.1 months (95% CI: 4.4-21.8) in the TACE-S group, a duration that was significantly longer than that in the TACE-alone group [5 months (95% CI: 6.4-13.3), p = 0.014]. This study demonstrated that sorafenib-related dermatologic AEs are clinical biomarkers to identify responders from all of the patients for TACE-S therapy. Sorafenib-related dermatologic AEs, clinical biomarkers, can predict the efficacy of TACE-S in future randomized controlled trials.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica , Neoplasias Hepáticas/terapia , Niacinamida/análogos & derivados , Compuestos de Fenilurea/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/mortalidad , Quimioembolización Terapéutica/efectos adversos , Quimioembolización Terapéutica/métodos , Progresión de la Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Niacinamida/administración & dosificación , Niacinamida/efectos adversos , Compuestos de Fenilurea/efectos adversos , Pronóstico , Estudios Retrospectivos , Sorafenib , Resultado del Tratamiento , Adulto Joven
14.
Neuroimage ; 63(4): 1827-32, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22951259

RESUMEN

Changes in regional brain activity can be observed following global normalization procedures to reduce variability in the data. In particular, spurious regional differences may appear when scans from patients with low global activity are compared to those from healthy subjects. It has thus been suggested that the consistent increases in subcortical activity that characterize the abnormal Parkinson's disease-related metabolic covariance pattern (PDRP) are artifacts of global normalization, and that similar topographies can be identified in scans from healthy subjects with varying global activity. To address this issue, we examined the effects of experimental reductions in global metabolic activity on PDRP expression. Ten healthy subjects underwent ¹8F-fluorodeoxyglucose PET in wakefulness and following sleep induction. In all subjects, the global metabolic rate (GMR) declined with sleep (mean -34%, range: -17 to -56%), exceeding the test-retest differences of the measure (p<0.001). By contrast, sleep-wake differences in PDRP expression did not differ from test-retest differences, and did not correlate (R²=0.04) with concurrent declines in global metabolic activity. Indeed, despite significant GMR reductions in sleep, PDRP values remained within the normal range. Likewise, voxel weights on the principal component patterns resulting from combined analysis of the sleep and wake scans did not correlate (R²<0.07) with the corresponding regional loadings on the PDRP topography. In aggregate, the data demonstrate that abnormal PDRP expression is not induced by reductions in global activity. Moreover, significant declines in GMR are not associated with the appearance of PDRP-like spatial topographies.


Asunto(s)
Encéfalo/patología , Red Nerviosa/patología , Enfermedad de Parkinson/patología , Adulto , Anciano , Análisis de Varianza , Encéfalo/diagnóstico por imagen , Química Encefálica/fisiología , Causalidad , Cerebelo/diagnóstico por imagen , Cerebelo/metabolismo , Cerebelo/patología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Interpretación Estadística de Datos , Femenino , Fluorodesoxiglucosa F18 , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/metabolismo , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/metabolismo , Tomografía de Emisión de Positrones , Análisis de Componente Principal , Radiofármacos , Sueño/fisiología , Tálamo/diagnóstico por imagen , Tálamo/metabolismo , Tálamo/patología
15.
J Cereb Blood Flow Metab ; 32(4): 633-42, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22126913

RESUMEN

Parkinson's disease (PD) is associated with a characteristic regional metabolic covariance pattern that is modulated by treatment. To determine whether a homologous metabolic pattern is also present in nonhuman primate models of parkinsonism, 11 adult macaque monkeys with parkinsonism secondary to chronic systemic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 12 age-matched healthy animals were scanned with [(18)F]fluorodeoxyglucose (FDG) positron emission tomography (PET). A subgroup comprising five parkinsonian and six control animals was used to identify a parkinsonism-related pattern (PRP). For validation, analogous topographies were derived from other subsets of parkinsonian and control animals. The PRP topography was characterized by metabolic increases in putamen/pallidum, thalamus, pons, and sensorimotor cortex, as well as reductions in the posterior parietal-occipital region. Pattern expression was significantly elevated in parkinsonian relative to healthy animals (P<0.00001). Parkinsonism-related topographies identified in the other derivation sets were very similar, with significant pairwise correlations of region weights (r>0.88; P<0.0001) and subject scores (r>0.74; P<0.01). Moreover, pattern expression in parkinsonian animals correlated with motor ratings (r>0.71; P<0.05). Thus, homologous parkinsonism-related metabolic networks are demonstrable in PD patients and in monkeys with experimental parkinsonism. Network quantification may provide a useful biomarker for the evaluation of new therapeutic agents in preclinical models of PD.


Asunto(s)
Trastornos Parkinsonianos/metabolismo , Putamen/metabolismo , Tálamo/metabolismo , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/efectos adversos , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Animales , Modelos Animales de Enfermedad , Dopaminérgicos/efectos adversos , Dopaminérgicos/farmacología , Femenino , Humanos , Macaca , Masculino , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/patología , Putamen/patología , Tálamo/patología
16.
Neuroimage ; 31(1): 301-7, 2006 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-16466936

RESUMEN

Deep brain stimulation of the subthalamic nucleus (STN DBS) has become an accepted tool for the treatment of Parkinson's disease (PD). Although the precise mechanism of action of this intervention is unknown, its effectiveness has been attributed to the modulation of pathological network activity. We examined this notion using positron emission tomography (PET) to quantify stimulation-induced changes in the expression of a PD-related covariance pattern (PDRP) of regional metabolism. These metabolic changes were also compared with those observed in a similar cohort of patients undergoing STN lesioning. We found that PDRP activity declined significantly (P < 0.02) with STN stimulation. The degree of network modulation with DBS did not differ from that measured following lesioning (P = 0.58). Statistical parametric mapping (SPM) revealed that metabolic reductions in the internal globus pallidus (GPi) and caudal midbrain were common to both STN interventions (P < 0.01), although declines in GPi were more pronounced with lesion. By contrast, elevations in posterior parietal metabolism were common to the two procedures, albeit more pronounced with stimulation. These findings indicate that suppression of abnormal network activity is a feature of both STN stimulation and lesioning. Nonetheless, these two interventions may differ metabolically at a regional level.


Asunto(s)
Estimulación Encefálica Profunda , Metabolismo Energético/fisiología , Procesamiento de Imagen Asistido por Computador , Red Nerviosa/fisiopatología , Enfermedad de Parkinson/rehabilitación , Tomografía de Emisión de Positrones , Núcleo Subtalámico/fisiopatología , Anciano , Análisis de Varianza , Glucemia/metabolismo , Mapeo Encefálico , Cerebelo/diagnóstico por imagen , Cerebelo/fisiopatología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiopatología , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/fisiopatología , Femenino , Fluorodesoxiglucosa F18 , Globo Pálido/diagnóstico por imagen , Globo Pálido/fisiopatología , Giro del Cíngulo/diagnóstico por imagen , Giro del Cíngulo/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/fisiopatología , Núcleo Subtalámico/diagnóstico por imagen , Tálamo/diagnóstico por imagen , Tálamo/fisiopatología
17.
Neurology ; 62(10): 1879-81, 2004 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-15159501

RESUMEN

Posthypoxic myoclonus (PHM) is a syndrome of action and intention myoclonus that occurs in some patients who survive a cardiac arrest. Using PET and statistical parametric mapping, the authors observed a significant bilateral increase in glucose metabolism in the ventrolateral thalamus and pontine tegmentum in patients relative to controls. Interventions such as deep brain stimulation that interrupt networks that involve these structures may be useful in patients with severe PHM.


Asunto(s)
Encéfalo/metabolismo , Paro Cardíaco/complicaciones , Hipoxia Encefálica/complicaciones , Mioclonía/etiología , Adulto , Vías Aferentes/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Vías Eferentes/diagnóstico por imagen , Femenino , Fluorodesoxiglucosa F18 , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Movimiento , Mioclonía/diagnóstico por imagen , Mioclonía/metabolismo , Mioclonía/patología , Radiofármacos , Tegmento Mesencefálico/diagnóstico por imagen , Tegmento Mesencefálico/metabolismo , Tegmento Mesencefálico/patología , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/metabolismo , Lóbulo Temporal/patología , Tálamo/diagnóstico por imagen , Tálamo/metabolismo , Tálamo/patología , Tomografía Computarizada de Emisión
18.
Neuroimage ; 21(4): 1497-507, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15050574

RESUMEN

In this study, we tested the hypotheses that (1) the acquisition of sequential information is related to the integrity of dopaminergic input to the caudate nucleus; and (2) the integrity of dopaminergic input to the caudate nucleus correlates significantly with brain activation during sequence acquisition. Twelve early stage Parkinson's disease (PD) patients and six age-matched healthy volunteers were scanned using a dual tracer PET imaging design. All subjects were scanned with [(18)F]fluoropropyl-betaCIT (FPCIT) to measure striatal dopamine transporter (DAT) binding and with [(15)O]water to assess activation during a sequence learning task where movements were made to a repeating sequence of eight targets. Caudate and putamen DAT binding in the PD cohort was reduced by 15% and 43%, respectively. In PD, caudate DAT binding correlated with target acquisition (R = 0.57, P < 0.05), while putamen DAT binding did not correlate with performance. In volunteers, caudate DAT binding correlated with learning-related activation (P < 0.05, corrected for multiple comparisons) in the left dorsolateral and ventral prefrontal cortices, the anterior cingulate and premotor regions, and the right cerebellum. A significant correlation with caudate DAT binding was additionally detected in the right anteromedial thalamus, extending into the rostral midbrain. By contrast, in the PD cohort, most of these regional relationships were lost: Only ventral and dorsolateral prefrontal cortex activation correlated with caudate dopaminergic tone. Our findings suggest that sequence learning is normally associated with tight coupling between dopaminergic input to the caudate and thalamo-cortical functional activity. Despite minimal reductions in nigro-caudate input, PD patients demonstrate a loss of this coupling early in the disease.


Asunto(s)
Nivel de Alerta/fisiología , Núcleo Caudado/diagnóstico por imagen , Cuerpo Estriado/diagnóstico por imagen , Dopamina/fisiología , Interpretación de Imagen Asistida por Computador , Glicoproteínas de Membrana , Proteínas de Transporte de Membrana/fisiología , Proteínas del Tejido Nervioso/fisiología , Enfermedad de Parkinson/diagnóstico por imagen , Aprendizaje Seriado/fisiología , Tomografía Computarizada de Emisión , Anciano , Mapeo Encefálico , Núcleo Caudado/fisiopatología , Cerebelo/diagnóstico por imagen , Cerebelo/fisiopatología , Cuerpo Estriado/fisiopatología , Dominancia Cerebral/fisiología , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Femenino , Radioisótopos de Flúor , Humanos , Cinestesia/fisiología , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Enfermedad de Parkinson/fisiopatología , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiopatología , Desempeño Psicomotor/fisiología , Putamen/diagnóstico por imagen , Putamen/fisiopatología , Tálamo/diagnóstico por imagen , Tálamo/fisiopatología , Tropanos
19.
Neuroimage ; 21(2): 608-15, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14980563

RESUMEN

We used (15)O-labeled water (H(2)(15)O) positron emission tomography (PET) to study eight Parkinson's disease (PD) patients with unilateral ventral intermediate (Vim) thalamic nucleus deep brain stimulation (DBS) for severe tremor. Triaxial accelerometry (TRIAX) was used during imaging to obtain on-line measures of tremor characteristics. Regional cerebral blood flow (rCBF) scans together with TRIAX recordings were collected in three stimulation conditions (OFF, MID, and ON, corresponding, respectively, to 0%, 50%, and 100% reductions in mean accelerometry signal). Statistical Parametric Mapping (SPM99) revealed significant rCBF reductions during stimulation in the ipsilateral sensorimotor cortex (SMC) and the contralateral cerebellum, as well as concurrent increases in the ipsilateral ventral thalamus (P < 0.05, corrected). Covariate analysis of rCBF with physiological tremor characteristics revealed that tremor acceleration correlated positively with changes in the SMC and supplementary motor cortex ipsilaterally (P < 0.05, uncorrected), and negatively with changes in the ipsilateral cuneus (P < 0.05, corrected). After removing tremor acceleration effects, changes in tremor frequency correlated negatively with changes in the contralateral dentate nucleus and pons (P < 0.05, uncorrected). Our results suggest that Vim DBS for PD tremor modulates the activity of cerebello-thalamo-cortical pathways. Specific tremor characteristics relate to activity in different nodes of this system.


Asunto(s)
Terapia por Estimulación Eléctrica , Procesamiento de Imagen Asistido por Computador , Enfermedad de Parkinson/terapia , Tomografía Computarizada de Emisión , Temblor/terapia , Núcleos Talámicos Ventrales/fisiopatología , Anciano , Mapeo Encefálico , Núcleos Cerebelosos/diagnóstico por imagen , Núcleos Cerebelosos/fisiopatología , Dominancia Cerebral/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Corteza Motora/diagnóstico por imagen , Corteza Motora/fisiopatología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/fisiopatología , Puente/diagnóstico por imagen , Puente/fisiopatología , Flujo Sanguíneo Regional/fisiología , Corteza Somatosensorial/diagnóstico por imagen , Corteza Somatosensorial/fisiopatología , Temblor/fisiopatología , Núcleos Talámicos Ventrales/diagnóstico por imagen
20.
Ann Neurol ; 52(2): 144-52, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12210783

RESUMEN

We used (15)O-labeled water and positron emission tomography to assess the effect of deep brain stimulation of the internal globus pallidus on motor sequence learning in Parkinson's disease. Seven right-handed patients were scanned on and off stimulation while they were performing a motor sequence learning task and a kinematically matched motor execution reference task. The scans were performed after a 12-hour medication washout. Stimulation parameters were adjusted for maximal motor improvement; experimental task parameters were held constant across stimulation conditions. Internal globus pallidus stimulation improved motor ratings by 37% (p < 0.01). During the sequence learning task, stimulation improved performance as measured by several correct anticipatory movements (p < 0.01) and by verbal report (p < 0.001). Concurrent positron emission tomography imaging during learning demonstrated significant (p < 0.01) increases in brain activation with stimulation in the left dorsolateral prefrontal cortex, bilaterally in premotor cortex, and in posterior parietal and occipital association areas. Stimulation did not affect the activity of these regions during the performance of the motor execution reference task. These findings suggest that internal globus pallidus deep brain stimulation can enhance the activity of prefrontal cortico-striato-pallidothalamic loops and related transcortical pathways. Improved sequence learning with stimulation may be directly related to these functional changes.


Asunto(s)
Encéfalo/fisiopatología , Terapia por Estimulación Eléctrica , Globo Pálido/fisiopatología , Aprendizaje/fisiología , Actividad Motora/fisiología , Trastornos Parkinsonianos/fisiopatología , Trastornos Parkinsonianos/terapia , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Femenino , Globo Pálido/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Trastornos Parkinsonianos/diagnóstico por imagen , Trastornos Parkinsonianos/psicología , Tomografía Computarizada de Emisión
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