Optimización superficial de alambres de ortodoncia de Ni-Ti superelástico mediante nitruración gaseosa. Parte II: Cuantificación de la mejora de la nanodureza y el coeficiente de fricción

La mejora del deslizamiento entre el alambre de ortodoncia y el bracket es uno de los principales problemas en la terapia ortodoncica. Este estudio presenta la nitruración gaseosa como un eficaz método de mejora del deslizamiento de los alambres ortodóncicos de Ni-Ti superelástico (composiciones cercanas a la equiatómica) respecto al bracket, principal inconveniente de estas aleaciones en la aplicación ortodóncica. Mediante microscopía óptica y electrónica de barrido se comprobó la existencia de una capa superficial nitrurada, así como la morfología de las fases presentes. Asimismo, se realizaron microanálisis químicos de las capas exteriores mediante técnica de energía dispersiva de rayos X. En todas las muestras nitruradas la dureza aumentó con la severidad del tratamiento y se alcanzaron valores de hasta 1111HV en comparación con los valores de 323 HV del alambre sin tratar. Se diseñaron ensayos de tipo pin on disk adaptados a las peculiaridades de los alambres, que mostraron un descenso del coeficiente de fricción. El endurecimiento y mejora de la fricción en la superficie del material se justifican por la formación de las capas nitruradas.Peer Reviewe

Active focal segmental glomerulosclerosis is associated with massive oxidation of plasma albumin

The basic mechanism for idiopathic FSGS still is obscure. Indirect evidence in humans and generation of FSGS by oxidants in experimental models suggest a role of free radicals. In vitro studies demonstrate a main role of plasma albumin as antioxidant, its modification representing a chemical marker of oxidative stress. With the use of complementary liquid chromatography electron spray ionization tandem mass spectrometry (LC-ESI-MS/MS) and biochemical methods, plasma albumin was characterized in 34 patients with FSGS; 18 had received a renal transplant, and 17 had IgM mesangial deposition. Patients with FSGS that was in remission or without recurrence after transplantation had normal plasma albumin, and the same occurred in patients with primary and secondary nephrites and with chronic renal failure. In contrast, patients with active FSGS or with posttransplantation recurrence had oxidized plasma albumin. This finding was based on the characterization of albumin Cys 34 with an mass-to-charge ratio of 511.71 in triple charge that was consistent with the formation of a cysteic acid carrying a sulfonic group (alb-SO3-). The exact mass of albumin was increased accordingly (+48 Da) for incorporation of three oxygen radicals. Direct titration of the free sulfhydryl group 34 of plasma albumin and electrophoretic titration curves confirmed loss of free sulfhydryl group and formation of a fast-moving isoform in all cases with disease activity. This is the first demonstration of in vivo plasma albumin oxidation that was obtained with an adequate structural approach. Albumin oxidation seems to be specific for FSGS, suggesting some pathogenetic implications. Free radical involvement in FSGS may lead to specific therapeutic interventions

Contrast sensitivity test and conventional and high frequency audiometry: information beyond that required to prescribe lenses and headsets

In Optometry and in Audiology, the routine tests to prescribe correction lenses and headsets are respectively the visual acuity test (the first chart with letters was developed by Snellen in 1862) and conventional pure tone audiometry (the first audiometer with electrical current was devised by Hartmann in 1878). At present there are psychophysical non invasive tests that, besides evaluating visual and auditory performance globally and even in cases catalogued as normal according to routine tests, supply early information regarding diseases such as diabetes, hypertension, renal failure, cardiovascular problems, etc. Concerning Optometry, one of these tests is the achromatic luminance contrast sensitivity test (introduced by Schade in 1956). Concerning Audiology, one of these tests is high frequency pure tone audiometry (introduced a few decades ago) which yields information relative to pathologies affecting the basal cochlea and complements data resulting from conventional audiometry. These utilities of the contrast sensitivity test and of pure tone audiometry derive from the facts that Fourier components constitute the basis to synthesize stimuli present at the entrance of the visual and auditory systems; that these systems responses depend on frequencies and that the patient's psychophysical state affects frequency processing. The frequency of interest in the former test is the effective spatial frequency (inverse of the angle subtended at the eye by a cycle of a sinusoidal grating and measured in cycles/degree) and, in the latter, the temporal frequency (measured in cycles/sec). Both tests have similar duration and consist in determining the patient's threshold (corresponding to the inverse multiplicative of the contrast or to the inverse additive of the sound intensity level) for each harmonic stimulus present at the system entrance (sinusoidal grating or pure tone sound). In this article the frequencies, standard normality curves and abnormal threshold shifts inherent to the contrast sensitivity test (which for simplicity could be termed "visionmetry") and to pure tone audiometry (also termed auditory sensitivity test) are analyzed with the purpose of contributing to divulge their ability to supply early information associated to pathologies not solely related to the visual and auditory systems respectively. © 2008 American Institute of Physics.Fil:Comastri, S.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Martin, G. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Simon, J.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Chronic oleoylethanolamide treatment decreases hepatic triacylglycerol level in rat liver by a pparγ/srebp-mediated suppression of fatty acid and triacylglycerol synthesis

none11noOleoylethanolamide (OEA) is a naturally occurring bioactive lipid belonging to the family of N-acylethanolamides. A variety of beneficial effects have been attributed to OEA, although the greater interest is due to its potential role in the treatment of obesity, fatty liver, and eating-related disorders. To better clarify the mechanism of the antiadipogenic effect of OEA in the liver, using a lipidomic study performed by1H-NMR, LC-MS/MS and thin-layer chromatography analyses we evaluated the whole lipid composition of rat liver, following a two-week daily treatment of OEA (10 mg kg−1 i.p.). We found that OEA induced a significant reduction in hepatic triacylglycerol (TAG) content and significant changes in sphingolipid composition and ceramidase activity. We associated the antiadipogenic effect of OEA to decreased activity and expression of key enzymes involved in fatty acid and TAG syntheses, such as acetyl-CoA carboxylase, fatty acid synthase, diacylglycerol acyltransferase, and stearoyl-CoA desaturase 1. Moreover, we found that both SREBP-1 and PPARγ protein expression were significantly reduced in the liver of OEA-treated rats. Our findings add significant and important insights into the molecular mechanism of OEA on hepatic adipogenesis, and suggest a possible link between the OEA-induced changes in sphingolipid metabolism and suppression of hepatic TAG level.openRomano A.; Friuli M.; Del Coco L.; Longo S.; Vergara D.; Del Boccio P.; Valentinuzzi S.; Cicalini I.; Fanizzi F.P.; Gaetani S.; Giudetti A.M.Romano, A.; Friuli, M.; Del Coco, L.; Longo, S.; Vergara, D.; Del Boccio, P.; Valentinuzzi, S.; Cicalini, I.; Fanizzi, F. P.; Gaetani, S.; Giudetti, A. M

Glycine-Stabilized Zinc Gluconate has similar bioavailability than Zinc Sulfate in a zinc fortified probiotic food

Objective: In this study, we evaluated zinc gluconate stabilized with glycine (GZ) and sulfate (SZ) in fermented milk as vehicle. Zinc bioavailability was evaluated in an animal model (Sprague Dawley rats) for both zinc sources in the vehicle with a probiotic (Lactobacillus casei DN114001). Results: For growth parameters, higher weight gain and femur weight values were observed when probiotic and zinc were provided together, independent of the source (weight gain: SZ 81.4g±4.0g; GZ 81.8g±4.0g and 70.2g±12.5g without the probiotic; femur weight: SZ 0.51g ±0.05g; GZ 0.52g±0.05g and 0.42g±0.03g without the probiotic). Femur zinc content was higher for zinc gluconate stabilized with glycine in the presence of the probiotic (97.04ppm±8.40ppm), and the results were similar for zinc sulfate with or without probiotic (84.51ppm±2.44ppm and 84.94ppm±2.28ppm, respectively). Serum antioxidant capacity and immune cellular response were also evaluated by using free radical scavenging assays and a T cell proliferation assay respectively. The free radical scavenging assay showed a tendency to increase with zinc provision, and the highest proliferation index was observed for glycine-stabilized zinc gluconate and the probiotic. Conclusion: The results indicate that the combination of zinc (as glycine-stabilized zinc gluconate) and a probiotic may be beneficial for the evaluated parameters.Fil: Tesan, Fiorella Carla. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hernández, F.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Torti, Horacio Emilio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Massot, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Huarte, M.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Rubín de Celis, E.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Barreiro Arcos, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Weill, R.. Danone Argentina S,a,; ArgentinaFil: Cremaschi, Graciela Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Boccio, J.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Salgueiro, María Jimena. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

The Epidemiologic Study in San Valentino

The efficacy of a 2-month treatment with oral colostrum in the prevention of flu episodes compared with antiinfluenza vaccination was evaluated. Groups included healthy subjects without prophylaxis and those receiving both vaccination and colostrum. After 3 months of follow-up, the number of days with flu was 3 times higher in the non-colostrum subjects. The colostrum group had 13 episodes versus 14 in the colostrum + vaccination group, 41 in the group without prophylaxis, and 57 in nontreated subjects. Part 2 of the study had a similar protocol with 65 very high-risk cardiovascular subjects, all of whom had prophylaxis. The incidence of complications and hospital admission was higher in the group that received only a vaccination compared with the colostrum groups. Colostrum, both in healthy subjects and high-risk cardiovascular patients, is at least 3 times more effective than vaccination to prevent flu and is very cost-effective

Corrigendum to “Circulating Cancer Stem Cell-Derived Extracellular Vesicles as a Novel Biomarker for Clinical Outcome Evaluation”

[This corrects the article DOI: 10.1155/2019/5879616.].Peer Reviewe

Circulating Cancer Stem Cell-Derived Extracellular Vesicles as a Novel Biomarker for Clinical Outcome Evaluation.

The recent introduction of the "precision medicine" concept in oncology pushed cancer research to focus on dynamic measurable biomarkers able to predict responses to novel anticancer therapies in order to improve clinical outcomes. Recently, the involvement of extracellular vesicles (EVs) in cancer pathophysiology has been described, and given their release from all cell types under specific stimuli, EVs have also been proposed as potential biomarkers in cancer. Among the techniques used to study EVs, flow cytometry has a high clinical potential. Here, we have applied a recently developed and simplified flow cytometry method for circulating EV enumeration, subtyping, and isolation from a large cohort of metastatic and locally advanced nonhaematological cancer patients (N = 106); samples from gender- and age-matched healthy volunteers were also analysed. A large spectrum of cancer-related markers was used to analyse differences in terms of peripheral blood circulating EV phenotypes between patients and healthy volunteers, as well as their correlation to clinical outcomes. Finally, EVs from patients and controls were isolated by fluorescence-activated cell sorting, and their protein cargoes were analysed by proteomics. Results demonstrated that EV counts were significantly higher in cancer patients than in healthy volunteers, as previously reported. More interestingly, results also demonstrated that cancer patients presented higher concentrations of circulating CD31+ endothelial-derived and tumour cancer stem cell-derived CD133 + CD326- EVs, when compared to healthy volunteers. Furthermore, higher levels of CD133 + CD326- EVs showed a significant correlation with a poor overall survival. Additionally, proteomics analysis of EV cargoes demonstrated disparities in terms of protein content and function between circulating EVs in cancer patients and healthy controls. Overall, our data strongly suggest that blood circulating cancer stem cell-derived EVs may have a role as a diagnostic and prognostic biomarker in cancer