Showing papers by "Mauro Serafini published in 2000"

Inhibition of human LDL lipid peroxidation by phenol-rich beverages and their impact on plasma total antioxidant capacity in humans.

Abstract: Mounting evidence shows that phenol-rich beverages exert strong antioxidant activity. However, in vivo evidence has produced conflicting results. In the present study, we studied the impact of the ingestion of 300 mL of black and green tea, alcohol-free red wine, alcohol-free white wine, or water on plasma total antioxidant capacity in five healthy volunteers. Red wine has the highest content of phenolics (3.63 ± 0.48 g QE/L), followed by green tea (2.82 ± 0.07 g QE/L), black tea (1.37 ± 0.15 g QE/L), and white wine (0.31 ± 0.01 g QE/L). Plasma total antioxidant capacity values of subjects who drank green tea rose at 30 min (P < 0.05). After black tea and red wine ingestion, the peaks were at 50 min (P < 0.05 and P < 0.01, respectively). No changes were observed in the control and white wine groups. Red wine and green tea were the most efficient in protecting low density lipoprotein from oxidation driven by peroxyl and ferril radicals, respectively. Phenol-rich beverages are a natural source of antioxidants; however, the phenolic content alone cannot be considered an index of their in vivo antioxidant activity.

Dietary antioxidant intake and the risk of cardia cancer and noncardia cancer of the intestinal and diffuse types: a population-based case-control study in Sweden

Abstract: In spite of diverging incidence trends, subsite, and subtype-specific gastric cancer data on the association with dietary antioxidants are sparse. We aimed to test whether the apparent protective effect of antioxidants is mainly confined to noncardia (distal) cancer of the intestinal subtype, to which most of the incidence decline in gastric cancer has been ascribed. In a Swedish study base (total population 1.3 million), we interviewed 567 cases uniformly classified to subsite (cardia vs. noncardia) and subtype (intestinal vs. diffuse), and 1165 population-based controls, frequency matched for age and sex. Serologic data on H. pylori status was available for a subset of 542 individuals. Ascorbic acid (vitamin C) was inversely associated with all subsites and subtypes of gastric cancer in a significant dose-response manner (all p<0.05), with risk reductions between 40% and 60%. beta-carotene was also strongly and negatively associated with risk, particularly with the intestinal type. The associations with alpha-tocopherol (vitamin E) were less clear. The highest parallel intake of all three antioxidants (quartiles 4), compared to those with the lowest parallel intakes (quartiles 1), was associated with a 70% lower risk of developing noncardia cancer (OR 0.3, 95% CI 0.1-0.9). Our results suggest that antioxidants might be especially beneficial among subjects at increased risk for gastric cancer such as smokers and those infected by H. pylori. We conclude that a high intake of antioxidants, as a consequence of high consumption of fruit and vegetables, may lower the risk not only for gastric cancer of the intestinal type, but also for diffuse type adenocarcinoma and cardia cancer.

Bis-iridoid glucosides from Abelia chinensis.

Abstract: Seven bis-iridoid glucosides have been isolated from Abelia chinensis and were characterized by having a secoiridoid residue as unit A esterifying a C10-iridoid or a δ-lactone iridoid as unit B. Among these, compounds 1−3 are new and correspond to 7-O-acetyllaciniatoside IV, 7-O-acetyllaciniatoside V, and 7-O-acetylabelioside B, respectively. The structures of 1−3 were elucidated by spectral methods.

Localizzazione cerebrale funzionale delle aree del linguaggio per mezzo di un compito di decisione lessicale

Abstract: La metodica di risonanza magnetica funzionale (fMRI) permette di esplorare le funzioni cognitive in vivo sull'uomo in modo non invasivo. In questo studio presentiamo i primi risultati di un progetto volto alla localizzazione delle aree cerebrali del linguaggio a scopo clinico per la valutazione prechirurgica e per il controllo riabilitativo di pazienti cerebrolesi. Sono stati studiati 10 soggetti sani destrimani e un paziente cerebroleso sinistro. E stata valutata la differenza di segnale di risonanza registrato con sequenza ecoplanare gradient-echo sensibile al segnale T2* comparando volumi cerebrali acquisiti in blocchi di 30 secondi. I soggetti eseguivano alternativamente un compito di decisione lessicale o un compito di decisione grafemica. I risultati dei dati ottenuti dai pazienti di controllo indicano una elevata sensibilita del test mettendo in evidenza tutte le aree note coinvolte nelle funzione linguistiche. L'analisi dei dati ottenuti dal paziente cerebroleso suggeriscono che il protocollo di s...

Aree corticali di rappresentazione bilaterale dei movimenti della mano

Abstract: Gli studi funzionali con PET e fMRI hanno dimostrato zone di attivazione nella corteccia motorio-sensoriale primaria ipsilaterale, che appare spazialmente piu estesa nell'emisfero dominante durante il movimento delle dita.Questo studio analizza la presenza e la distribuzione spaziale controlaterale, bilaterale ed ipsilaterale della rappresentazione motoria di entrambi gli emisferi con RM ecoplanare.L'esame RM funzionale ha dimostrato differenti popolazioni neuronali con caratteristiche funzioni specifiche in zone anatomicamente definite. Non si e osservata rappresentazione del movimento puramente monolaterale; la componente ipsilaterale di attivazione corticale sembra riflettere una popolazione neuronale attivata durante movimenti sia della mano destra che sinistra, con estensione maggiore nell'emisfero dominante.Questa popolazione bilaterale e presumibilmente coinvolta nella pianificazione del movimento. Una popolazione secondaria, attivata solo durante il movimento controlaterale, e stata identificata i...