1,721,180 research outputs found
Giuseppe Moscati (1880-1927): a holistic approach to medicine
No full textGiuseppe Moscati was a physician, medical school professor and a pioneer in the field of biochemistry and Italian studies on diabetes. He was declared a Catholic saint in 1987. In order to respond better to both the physical and spiritual needs of his patients, he developed his own holistic approach to healthcare involving meticulous drug regimens, meditation and discipline
Hydroxyl free radical production in iron-cysteine solutions and protection by zinc
No full textHydroxyl radicals (OH−) can be formed on incubation of an oxygenated solution of ferrous sulphate and cysteine. This has been demonstrated by esr using the spin trap DMPO (5,5-dimethyl-1-pyrroline-1-oxide), catalase, and the radical scavengers ethanol and propan-2-ol. Hydroxyl radicals are not formed when excess zinc sulphate is present. These results provide support for the pro-oxidant action of iron and cysteine and a possible protective role for zinc
NITROXIDE RADICALS, THEIR USE AS METABOLIC PROBES IN BIOLOGICAL MODEL SYSTEMS - AN OVERVIEW
No full textThe concept of using a probe, sensitive to the environment, termed >>reporter group>reporter group>reporter group<< was later dismissed and the term spin label or spin probe preferred. The facile synthesis and the multiplicity of compounds which have been coupled to the nitroxide moiety has allowed the development of a number of applications including molecular mobility of proteins and lipids in membranes, study of the enzyme active site and DNA synthesis, measurement of electrical potential, measurement of pH, temperature and oxygen gradients across membranes and, more recently, as contrast agents in magnetic resonance imaging and electron paramagnetic resonance imaging. The overview, by no means comprehensive of the complete literature, aims to give an insight view of nitroxide applications as metabolic probes in the field of biomedical studies reporting methodologies and trying to give a critical view of the procedures and methodologies used
Il Progetto della Facoltà di Medicina e Chirurgia della Università di Modena e Reggio Emilia "Le Cure Primarie nel CDL in Medicina e Chirurgia"
No full textViene descritto il Progetto Didattico realizzato nel CDL in Medicina e Chirurgia della Università di Modena e Reggio Emilia allo scopo di sviluppare una formazione di base nell'area delle Cure Primarie, come auspicato dal DM 28.11.2000. Sono descritte le caratteristiche generali del Corso in termini di finalità, obiettivi formativi, modalità didattiche, docenti, setting formativi e aspetti organizzativi. Viene focalizzata l'attenzione sul carattere di "Corso Integrato" che il Progetto viene ad assumere, essendo basato sulla collaborazione fra Docenti Universitari e Professionisti di Azienda USL, compresi i medici di medicina generale. Viene focalizzata l'attenzione anche sulla "Didattica teorico-pratica" basata su seminari integrati fra Docenti Universitari e Professionisti aziendali e didattica tutoriale negli ambulatori dei mmg e in altri setting delle CP
SPIN-TRAPPING OF ALCOHOL-DERIVED RADICALS IN MICROSOMES AND RECONSTITUTED SYSTEMS BY ELECTRON-SPIN-RESONANCE
No full text*Alcohols metabolism; *Cytochrome P 450 Enzyme System metabolism; *Electron Spin Resonance Spectroscopy methods; *Microsomes, Liver metabolism; *Spin LabelsAlcohols analysis; Cytochrome P 450 Enzyme System antagonists and inhibitors; Free Radicals analysis; Indicators and Reagents; NADP metabolism; Nitrogen Oxides; Oxidation Reduction; Rats ; Rats, Sprague Dawley; Rats, Wistaranalysis; metabolism; antagonists and inhibitors; methodsCAS: 0; 0; 0; 0; 0; 0; 53 59 8; 9035 51
Generation of N-tert-butyl-alpha-phenylnitrone radical adducts in iron breakdown of tert-butyl-hydroperoxide
No full textESR spectroscopy coupled to the spin trapping technique was used to evaluate the generation of radical species arising from the ferrous ion induced decomposition of tert-butyl hydroperoxide ('BuOOH) in methylene chloride. We report here that N-tert-butyl-alpha-phenylnitrone (PEN) can trap peroxyl radicals generated in the ferrous ion induced breakdown of high concentration of 'BuOOH (1M) at room temperature, the radical adduct being stable under the light. The peroxyl radical formation was demonstrated by direct ESR measurements at 77K. In contrast, alkoxyl and methyl radicals were trapped only in the presence of low hydroperoxide concentration (1mM). In order to measure the hyperfine splitting constants (hfsc) of the PEN-methyl adduct spectra were obtained in the presence of diphenylamine (DPA) or 2,6-di-tert-butyl-4-methylphenol (BHT), which quenched the alkoxyl radical. For this latter radical, the hfsc were calculated by computer simulation. A mechanism for a direct interaction between DPA and the alkoxyl radical is presented. DPA quenched the peroxyl radical in the reaction of high hydroperoxide concentrations, with the concomitant generation of a DPA nitrogen-based radical
α-Tocopherol amplifies benzoyl peroxide free radical decomposition in a chemical system
No full textBenzoyl peroxide is commonly used in the treatment of acne, even though some adverse effects have been reported, probably mediated by the formation of peroxide-derived free radicals and the depletion of antioxidants. In the present work we have studied, in a chemical system, the effect of a-tocopherol on benzoyl peroxide radical decomposition to analyse the presence of an interaction between these two compounds, leading to an enhanced peroxide-cytotoxicity, as we have previously reported. Under our experimental conditions alpha-tocopherol strongly amplified the peroxide free radical decomposition occurring either in the presence or in the absence of UV irradiation, and lead to the formation of an unknown radical species in addition to benzoyloxy, phenyl and tocopheroxyl free radicals. The results of this study show that the enhancement of benzoyl peroxide toxicity in cells exposed simultaneously to this peroxide and alpha-tocopherol, is likely due to the generation of the detected radical species
Intracellular chromium reduction
No full textTwo steps are involved in the uptake of Cr(VI): (1) the diffusion of the anion CrO2−4 through a facilitated transport system, presumably the non-specific anion carrier and (2) the intracellular reduction of Cr(VI) to Cr(III). The intracellular reduction of Cr(VI), keeping the cytoplasmic concentration of Cr(VI) low, facilitates accumulation of chromate from extracellular medium into the cell. In the present paper, a direct demonstration of intracellular chromium reduction is provided by means of electron paramagnetic (spin) resonance (EPR) spectroscopy. Incubation of metabolically active rat thymocytes with chromate originates a signal which can be attributed to a paramagnetic species of chromium, Cr(V) or Cr(III). The EPR signal is originated by intracellular reduction of chromium since: (1) it is observed only when cells are incubated with chromate, (2) it is present even after extensive washings of the cells in a chromium-free medium; (3) it is abolished when cells are incubated with drugs able to reduce the glutathione pool, i.e., diethylmaleate or phorone; and (4) it is abolished when cells are incubated in the presence of a specific inhibitor of the anion carrier, 4-acetamido-4′-isothiocyanatostilbene-2-2′-disulfonic acid
Free Radicals, Nitric Oxide, and Inflammation: Molecular, Biochemical and Clinical Aspects
No full textInflammation is the local response of a complex organism to an injury that serves as a mechanism initiating the elimination of noxious agents and of damaged tissues. It is now well understood that damaging mechanisms at the basis of very common human pathologies, such as atherosclerosis, neurodegenerative diseases, and cancer, i.e. the most common human pathologies are driven by the inflammatory process. Free radicals, and the very special free radical nitric oxide, are playing a relevant role in the pathogenesis of inflammation. The initial chapters introduce to the general knowledge necessary to understand the inflammatory process and the role played by free radical and oxidative stress. The interplay between inflammatory molecules and cell signaling is also dealt with in depth. A second part is dedicated to nitric oxide, redox regulation and antioxidant function in inflammation. The final chapters are devoted to diseases where inflammation plays the dominant role: septic shock, end-stage renal disease, neurodegenerative, ischemic and lung diseases. This book, while not covering the whole gamut of the massive literature on inflammation and human diseases, gives an updated and concise view on the major issues concerning the pivotal role of inflammation in so many different human pathologies. At the same time it gives directions for future paths of research leading to a control of the pathologic process
Mismatch Repair Gene Deficiency and Genetic Anticipation in Lynch Syndrome
No full textLynch syndrome; mismatch repair gene
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