158 research outputs found
Il "tipo"
No full textIl contributo si propone di evidenziare come il "tipo s.r.l." a seguito delle modifiche intervenute negli ultimi anni non rechi più le caratteristiche tipologiche di un tempo, presentandosi, invece, come un tipo destrutturato: una "forma senza tipo"
Regioselective Syntheses of Optically Active (R)-5-Methyl- and (R)-Methyl-5,6,7,8-tetrahydroquinoline
No full text
Effect of biventricular pacing on ventilatory and perceptual responses to exercise in patients with stable chronic heart failure
No full textLaveneziana P, O'Donnell DE, Ofir D, Agostoni P, Padeletti L, Ricciardi G, Palange P, Duranti R, Scano G. Effect of biventricular pacing on ventilatory and perceptual responses to exercise in patients with stable chronic heart failure. J Appl Physiol 106: 1574-1583, 2009. First published February 26, 2009; doi:10.1152/japplphysiol.90744.2008.-Despite the growing evidence supporting the use of biventricular cardiac resynchronization therapy (CRT) in patients with chronic heart failure (CHF), the mechanisms whereby acute hemodynamic improvements lead to improved exertional dyspnea are not precisely known. We hypothesized that improved cardiac function and ventilation-perfusion relations following CRT would reduce ventilatory demand, thereby improving dynamic operating lung volumes and enhancing tidal volume expansion during exercise. This, in turn, would be expected to reduce perceived exertional dyspnea and contribute to improved exercise performance. In a randomized, double-blind, crossover study, we compared cardiovascular, metabolic, ventilatory responses (breathing pattern, operating lung volumes, pulmonary gas exchange) and exertional symptoms in seven stable CHF patients who undertook incremental cardiopulmonary cycle exercise test with CRT switched to the "on" (CRT(on)) or "off" (CRT(off)) modality. Following CRT(on), peak oxygen uptake was significantly increased by 15%, and dyspnea ratings were lower for a given work rate (at work rate of 40 W, dyspnea = 1 +/- 0.4 vs. 2.5 +/- 0.9 Borg units, P < 0.05) and ventilation (at ventilation of 31 l/min, dyspnea = 2 +/- 0.7 vs. 3.3 +/- 1.1 Borg units, P < 0.05). CRT(on) was associated with improvements in ventilatory threshold, oxygen pulse, and oxygen uptake/work rate relationships (10.2 +/- 1 vs. 7.9 +/- 1.3 ml.min(-1).W(-1), P < 0.05). CRT(on) reduced the ventilatory requirement during exercise as well as the steepness of ventilation-CO(2) production slope (35 +/- 4 vs. 45 +/- 7, P < 0.05). Changes in end-expiratory lung volume during exercise were less with CRT(on) than with CRT(off) (0.12 vs. 0.37 liter, P < 0.05), and breathing pattern was correspondingly slower and deeper. Biventricular pacing improved all noninvasive indexes of cardiac function and oxygen delivery during exercise. The decreased ventilatory demand, improved dynamic operating lung volumes, and the increased ability to expand tidal volume during exercise are potential factors in the reduction of exertional dyspnea
1H NMR metabolite fingerprinting as a new tool for body fluid identification in forensic science
No full textIn this feasibility study, we propose, for the first time, (1)H NMR spectroscopy coupled with mathematical strategies as a valid tool for body fluid (BF) trace identification in forensic science. In order to assess the ability of this approach to identify traces composed either by a single or by two different BFs, samples of blood, urine, saliva, and semen were collected from different donors, and binary mixtures were prepared. (1)H NMR analyses were carried out for all samples. Spectral data of the whole set were firstly submitted to unsupervised principal component analysis (PCA); it showed that samples of the same BF cluster well on the basis of their characterizing molecular components and that mixtures exhibit intermediate characteristics among BF typologies. Furthermore, samples were divided into a training set and a test set. An average NMR spectral profile for each typology of BF was obtained from the training set and validated as representative of each BF class. Finally, a fitting procedure, based on a system of linear equations with the four obtained average spectral profiles, was applied to the test set and the mixture samples; it showed that BFs can be unambiguously identified, even as components of a mixture. The successful use of this mathematical procedure has the advantage, in forensics, of overcoming bias due to the analyst's personal judgment. We therefore propose this combined approach as a valid, fast, and non-destructive tool for addressing the challenges in the identification of composite traces in forensics
Changes in the oral status and periodontal pathogens in a Sardinian rural community from pre-industrial to modern time
No full textThe oral microbial profile in humans has evolved in response to lifestyle changes over the course of different eras. Here, we investigated tooth lesions and the microbial profile of periodontal bacteria (PB) in dental calculus of a Sardinian pre-industrial rural community. In total, 51 teeth belonging to 12 historical individuals buried in an ossuary in the early 1800s and 26 modern teeth extracted from 26 individuals from the same geographical area were compared to determine the oral health status, bacterial load and amount of most relevant PB. Total caries and bacterial genomes count appeared to be sex-related in historical samples. Historical females presented a higher incidence of caries, PB pathogens and a higher bacterial load than historical males. Furthermore, we compared the PB profile of the historical individuals with the modern ones, revealing a notable increase in modern individuals of PB belonging to “Red complex bacteria” often associated with periodontitis and other chronic diseases of modern life. Our findings could be explained through an analysis of environmental factors such as socioeconomic, hygienic and healthy conditions that can have a great impact on oral health and bacterial composition among individuals of the same and different era
A metabolomic approach to animal vitreous humor topographical composition: A pilot study
No full textThe purpose of this study was to evaluate the feasibility of a 1H-NMR-based metabolomic approach to explore the
metabolomic signature of different topographical areas of vitreous humor (VH) in an animal model. Five ocular globes were
enucleated from five goats and immediately frozen at 280uC. Once frozen, three of them were sectioned, and four samples
corresponding to four different VH areas were collected: the cortical, core, and basal, which was further divided into a
superior and an inferior fraction. An additional two samples were collected that were representative of the whole vitreous
body. 1H-NMR spectra were acquired for twenty-three goat vitreous samples with the aim of characterizing the
metabolomic signature of this biofluid and identifying whether any site-specific patterns were present. Multivariate
statistical analysis (MVA) of the spectral data were carried out, including Principal Component Analysis (PCA), Hierarchical
Cluster Analysis (HCA), and Partial Least Squares Discriminant Analysis (PLS-DA). A unique metabolomic signature belonging
to each area was observed. The cortical area was characterized by lactate, glutamine, choline, and its derivatives, N-acetyl
groups, creatine, and glycerol; the core area was characterized by glucose, acetate, and scyllo-inositol; and the basal area
was characterized by branched-chain amino acids (BCAA), betaine, alanine, ascorbate, lysine, and myo-inositol. We propose
a speculative approach on the topographic role of these molecules that are mainly responsible for metabolic differences
among the as-identified areas. 1H-NMR-based metabolomic analysis has shown to be an important tool for investigating the
VH. In particular, this approach was able to assess in the samples here analyzed the presence of different functional areas on
the basis of a different metabolite distribution.The purpose of this study was to evaluate the feasibility of a 1H-NMR-based metabolomic approach to explore the metabolomic signature of different topographical areas of vitreous humor (VH) in an animal model. Five ocular globes were enucleated from five goats and immediately frozen at -80°C. Once frozen, three of them were sectioned, and four samples corresponding to four different VH areas were collected: the cortical, core, and basal, which was further divided into a superior and an inferior fraction. An additional two samples were collected that were representative of the whole vitreous body. 1H-NMR spectra were acquired for twenty-three goat vitreous samples with the aim of characterizing the metabolomic signature of this biofluid and identifying whether any site-specific patterns were present. Multivariate statistical analysis (MVA) of the spectral data were carried out, including Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), and Partial Least Squares Discriminant Analysis (PLS-DA). A unique metabolomic signature belonging to each area was observed. The cortical area was characterized by lactate, glutamine, choline, and its derivatives, N-acetyl groups, creatine, and glycerol; the core area was characterized by glucose, acetate, and scyllo-inositol; and the basal area was characterized by branched-chain amino acids (BCAA), betaine, alanine, ascorbate, lysine, and myo-inositol. We propose a speculative approach on the topographic role of these molecules that are mainly responsible for metabolic differences among the as-identified areas. 1H-NMR-based metabolomic analysis has shown to be an important tool for investigating the VH. In particular, this approach was able to assess in the samples here analyzed the presence of different functional areas on the basis of a different metabolite distribution. © 2014 Locci et al
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