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UNA VISIONE DI GENERE PER LE MALATTIE RARE IN TOSCANA
No full text,Introduzione Le malattie rare (MR) includono circa 7-8.000 patologie con una bassa diffusione nella popolazione (prevalenza <5/10.000). In accordo con le raccomandazioni dell\u27UE, il DM 279/2001 prevedeva l\u27istituzione della Rete nazionale dei Presidi dedicati all\u27attivit? di prevenzione,sorveglianza, diagnosi e terapia sulle MR, e la creazione del Registro nazionale a cui sono seguiti Registri regionali. Il DM definisce anche le modalit? di esenzione per un elenco di MR. Il RegistroToscano Malattie Rare (RTMR), entrato a regime nel 2006, ? gestito dalla Fondazione Toscana "Gabriele Monasterio" di Pisa. Obiettivi Individuare differenze nella distribuzione di genere per le MR incluse nel registro. Metodi Sono state selezionate 35 MR con almeno 30 nuovi casi diagnosticati nel periodo 2008-2012 (casi incidenti). Il rapporto tra sessi (RS) ? stato confrontato col valore atteso sulla base di quanto osservato nella popolazione toscana nello stesso periodo. Il rapporto tra il numero di maschi osservati (O) rispetto agli attesi (A) ? stato testato senza e con aggiustamento per 5 classi di et? (0-19; 20-39; 40-59; 60-79; >79 anni) con metodo indiretto, applicando il RS osservato in ciascuna classe di et? della popolazione di riferimento alla stessa classe di et? della MR analizzata. La differenza tra O e A ? stata valutata mediante test ?[al quadrato] con 1 GdL o con probabilit? esatta di Poisson quando i casi attesi erano inferiori a 10. Risultati Tra i 27.344 casi registrati al giugno 2013 le femmine rappresentano complessivamente il 54%. I maschi sono pi? rappresentati nei gruppi respiratorio (65%), sangue (61%) e malformazioni congenite (53%), mentre le femmine sono pi? rappresentate nei gruppi osteomuscolare (86%), digerente (70%) e circolatorio(69%). Sono risultate significativamente pi? frequenti tra i maschi, per specifiche classi di et?,rispetto alla popolazione di confronto: Sindrome di Klinefelter (tutti maschi); Malattie interstiziali polmonari primitive (RS= 2,83); Cheratocono (RS=2,38), Emocromatosi ereditaria (RS=2,15),Lichen sclerosus et atrophicus (RS=1,71); Sindrome di Down (RS=1,43). Per 9 MR ? stato osservato un eccesso di maschi, non significativo. Un RS <1,0, cio? un eccesso di femmine,statisticamente significativo ? stato rilevato per: Connettiviti indifferenziate (RS=0,08); Sclerosisistemica (RS=0,16); Arterite a cellule giganti (RS=0,25); Polimiosite (RS=0,27); Ipertensione polmonare arteriosa idiopatica (RS=0,34); Sprue celiaca (RS=0,41); Immunodeficienze primarie (RS=0,71); Miastenia grave (RS=0,77); Pemfigoide bolloso (RS=0,87). Eccessi di femmine non significativi sono stati individuati per altre 10 MR. Conclusioni L\u27informazione sulla differente distribuzione per sesso e per et? dei casi con MR rispetto alla popolazione generale ? rilevante per la pianificazione dei servizi mirati per la diagnosi, cura, riabilitazione e sostegno sociale, in grado di tener conto dei diversi bisogni e della diversa domanda espressa con una visione di genere
A new coronary circulation model for hybrid applications.
No full textAim: The Waterfall model of the coronary circulation in a whole computational circulatory model used in hybrid cardiovascular simulator (HCS) has several limitations. The aim of this study is to develop a new computational coronary circulation model (CCM) useful for HCS applications. Methods: The new CCM is based on a time-varying normalized impedance, whose resistive component is strongly nonlinear and depends on the phase of the cardiac cycle. The CCM was integrated in the HCS together with the base computational circulatory model, where the left and right ventricles are represented by time-varying elastance and systemic and pulmonary circulation are lumped Windkessel models. Starting from the HCS reproducing the same patho-physiological conditions, two groups of simulations were performed: one with the Waterfall and one with the new CCM. Then, a comparison between the two groups of results was performed. Results: Using the HCS in real-time modality, time courses of coronary flow, aortic, left ventricular and right atrial pressures were collected. Results show that in comparison to the simple CCM, the new CCM better reproduces nonlinear coronary flow pattern, according to the reference data from literature. Conclusions: The presented new CCM is able to reproduce the proper coronary flow pattern and is useful for HCS applications related especially to intraaortic balloon pump assistance investigations
Autoregulation unit for adaptive control of VADs: experimental scenario on a cardiovascular hybrid simulator.
No full textAim: The use of VAD as destination therapy points out the need of new therapy approaches of VAD control. In this work an innovative integrated autoregulation system for controlling a sensorized VAD is presented and tested by means of a hybrid cardiovascular simulator. Methods: The ARU is an autonomous system able to automatically respond to physiological cardiac demand and to the dynamic evolution of patient\u27s cardiovascular status. In the present work the ARU was connected to a cardiovascular simulator able to reproduce a wide range of pathologies and hemodynamic conditions. In this scenario, ARU autoregulation capabilities and remote control have been tested in order to show the feasibility of the approach. Results: The capability of the ARU to control from remote the pump integrated in the hybrid simulator has been tested in dedicated experiments of speed control. Additional experiments permitted to test the autoregulation control while changing the hemodynamic conditions on the simulator. Conclusions: The experiments show the ARU permits to control VAD speed settings both through a local controller and via wireless with response time below 1 s. When active, the autoregulation flow control detects the change of hemodynamic conditions and effectively reacts to keep VAD flow in a desired range within few seconds. Acknowledgments: work supported by SensorART (N. 248763) project
Reproduction of continuous flow lvad experimental data by means of a hybrid cardiovascular model with baroreflex control.
No full textLong-term mechanical circulatory assistance opened new problems in ventricular assist device-patient interaction, especially in relation to autonomic controls. Modeling studies, based on adequate models, could be a feasible approach of investigation. The aim of this work is the exploitation of a hybrid (hydronumerical) cardiovascular simulator to reproduce and analyze in vivo experimental data acquired during a continuous flow left ventricular assistance. The hybrid cardiovascular simulator embeds three submodels: a computational cardiovascular submodel, a computational baroreflex submodel, and a hydronumerical interface submodel. The last one comprises two impedance transformers playing the role of physical interfaces able to provide a hydraulic connection with specific cardiovascular sites (in this article, the left atrium and the ascending/descending aorta). The impedance transformers are used to connect a continuous flow pump for partial left ventricular support (Synergy Micropump, CircuLite, Inc., Saddlebrooke, NJ, USA) to the hybrid cardiovascular simulator. Data collected from five animals in physiological, pathological, and assisted conditions were reproduced using the hybrid cardiovascular simulator. All parameters useful to characterize and tune the hybrid cardiovascular simulator to a specific hemodynamic condition were extracted from experimental data. Results show that the simulator is able to reproduce animal-specific hemodynamic status both in physiological and pathological conditions, to reproduce cardiovascular left ventricular assist device (LVAD) interaction and the progressive unloading of the left ventricle for different pump speeds, and to investigate the effects of the LVAD on baroreflex activity. Results in chronic heart failure conditions show that an increment of LVAD speed from 20?000 to 22?000?rpm provokes a decrement of left ventricular flow of 35% (from 2 to 1.3?L/min). Thanks to its flexibility and modular structure, the simulator is a platform potentially useful to test different assist devices, thus providing clinicians additional information about LVAD therapy strategy
Determination of different forms of aminothiols in red blood cells without washing erythrocytes
Get PDFDetection and quantification of different aminothiols forms (reduced and total) in biological fluids are important for the investigation of oxidative stress-related diseases and cell homeostasis study. The aim of this study was to optimize a HPLC method in order to determine both reduced and total thiol forms in red blood cells (RBC) at low temperature without washing erythrocytes. Analytical recoveries for total and reduced thiols were 91.6-98.5 and 94.9-98.2% respectively. The relative standard deviations intra-assay for total and reduced thiols were 1.14-3.64 and 0.83-2.3% respectively and the relative standard deviations inter-assay for total and reduced thiols were 1.12-3.54 and 0.84-2.03%, respectively. This method allows specific analysis of the aminothiol state inside the RBC, as a model of intracellular metabolism functionin
Acute cigarette smoking impairs microvascular function in young moderate smokers: A potential model for studying vasoactive properties of food bioactives
Get PDFIt has been suggested that several dietary compounds may improve endothelial dysfunction and oxidative stress induced by smoking. We investigated the effects of acute smoking on blood pressure, heart rate (HR), peripheral arterial function (reactive hyperemia index, RHI), and arterial stiffness in young smokers by Endo-PAT2000. Twenty subjects that smoked an average of 15 cigarettes per day participated in the study. Reactive Hyperemia Index, arterial stiffness, blood pressure and HR were assessed before and after smoking one cigarette. Acute smoking significantly reduced RHI by 28% while increased arterial systolic ( + 14%) and diastolic ( + 10%) blood pressure and HR ( + 13%) at 5 min, while no effect was observed after 30 min. Arterial stiffness was not significantly affected. A significant, positive correlation was found between total serum cholesterol concentration and post-smoking arterial stiffness values. This study demonstrates that acute cigarette smoking impairs RHI and vital signs in young moderate smokers as evaluated through a non-invasive technique. Additionally, the experimental model described, where a decrease of RHI is induced by cigarette smoking, may be useful to study the impact of dietary vasoactive compounds on endothelial function
A single serving of blueberry (V. corymbosum) modulates peripheral arterial dysfunction induced by acute cigarette smoking in young volunteers: a randomized-controlled trial
Get PDFCigarette smoking causes oxidative stress, hypertension and endothelial dysfunction. Polyphenol-rich foods may prevent these conditions. We investigated the effect of a single serving of fresh-frozen blueberry intake on peripheral arterial function and arterial stiffness in young smokers. Sixteen male smokers were recruited for a 3-armed randomized-controlled study with the following experimental conditions: smoking treatment (one cigarette); blueberry treatment (300 g of blueberry) + smoking; control treatment (300 mL of water with sugar) + smoking. Each treatment was separated by one week of wash-out period. The blood pressure, heart rate, peripheral arterial function (reactive hyperemia and Framingham reactive hyperemia), and arterial stiffness (digital augmentation index, digital augmentation index normalized for a heart rate of 75 bpm) were measured before and 20 min after smoking with Endo-PAT2000. Smoking impaired the blood pressure, heart rate and peripheral arterial function, but did not affect the arterial stiffness. Blueberry consumption counteracted the impairment of the reactive hyperemia index induced by smoking (?\u274.4 ? 0.8% blueberry treatment vs. ?\u2722.0 ? 1.1% smoking treatment, p < 0.01) and Framingham reactive hyperemia (+28.3 ? 19.2% blueberry treatment vs. ?\u2742.8 ? 20.0% smoking treatment, p < 0.0001), and the increase of systolic blood pressure (+8.4 ? 0.02% blueberry treatment vs. +13.1 ? 0.02% smoking treatment, mmHg, p < 0.05) after cigarette smoking. No effect was observed for arterial stiffness and other vital signs. In conclusion, data obtained suggest a protective role of blueberry on reactive hyperemia, Framingham reactive hyperemia, and systolic blood pressure in subjects exposed to smoke of one cigarette. Future studies are necessary to elucidate the mechanisms involved
Holt Oram syndrome: a registry-based study in Europe
Get PDFBackground: Holt-Oram syndrome (HOS) is an autosomal dominant disorder characterised by upper limb anomalies and congenital heart defects. We present epidemiological and clinical aspects of HOS patients using data from EUROCAT (European Surveillance of Congenital Anomalies) registries. Methods: The study was based on data collected during 1990-2011 by 34 registries. The registries are population-based and use multiple sources of information to collect data on all types of birth using standardized definitions,methodology and coding. Diagnostic criteria for inclusion in the study were the presence of radial ray abnormalities and congenital heart disease (CHD), or the presence of either radial ray anomaly or CHD, with family history of HOS. Results: A total of 73 cases of HOS were identified, including 11 (15.1%) TOPFA and 62 (84.9%) LB. Out of 73 HOS cases, 30.8% (20/65) were suspected prenatally, 55.4% (36/65) at birth, 10.7% (7/65) in the first week of life, and 3.1%(2/65) in the first year of life. The prenatal detection rate was 39.2% (20/51), with no significant change over the study period. In 55% (11/20) of prenatally detected cases, parents decided to terminate pregnancy. Thumb anomalies were reported in all cases. Agenesis/hypoplasia of radius was present in 49.2% (30/61), ulnar aplasia/hypoplasia in 24.6% (15/61) and humerus hypoplasia/phocomelia in 42.6% (26/61) of patients. Congenital heart defects (CHD) were recorded in 78.7% (48/61) of patients. Isolated septal defects were present in 54.2 (26/48), while 25% (12/48) of patients had complex/severe CHD. The mean prevalence of HOS diagnosed prenatally or in the early years of life in European registries was 0.7 per 100,000 births or 1:135,615 births. Conclusions: HOS is a rare genetic condition showing regional variation in its prevalence. It is often missed prenatally, in spite of the existence of major structural anomalies. When discovered, parents in 45% (9/20) of cases opt for the continuation of pregnancy. Although a quarter of patients have severe CHD, the overall first week survival is very good, which is important information for counselling purposes
Towards a Timely Prediction of Earthquake Intensity with Social Media
Get PDFA growing number of people is turning to Social Media in the aftermath of emergencies to search and publish critical and up to date information. Retrieval and exploitation of such information may prove crucial to decision makers in order to minimize the impact of disasters on the population and the infrastructures. Yet, to date, the task of the automatic assessment of the consequences of disasters has received little to no attention. Our work aims to bridge this gap, merging the theory behind statistical learning and predictive models with the data behind social media. Here we investigate the exploitation of Twitter data for the improvement of earthquake emergency management. We adopt a set of predictive linear models and evaluate their ability to map the intensity of worldwide earthquakes. The models build on a dataset of almost 5 million tweets and more than 7,000 globally distributed earthquakes. We run and discuss diagnostic tests and simulations on generated models to assess their significance and avoid overfitting. Finally we deal with the interpretation of the relations uncovered by the linear models and we conclude by illustrating how findings reported in this work can be leveraged by existing emergency management systems. Overall results show the effectiveness of the proposed techniques and allow to obtain an estimation of the earthquake intensity far earlier than conventional methods do. The employment of the proposed solutions can help understand scenarios where damage actually occurred in order to define where to concentrate the rescue teams and organize a prompt emergency response
Comparative analysis of the hydrodynamic performance of untwisted and twisted rudders using a hybrid RANSE/BEM model
No full textResults of a computational study on the hydrodynamic performance of twisted and untwisted rudders for a single screw vessel are presented. Ship flow simulations are performed by using a hybrid RANSE/BEM model. Numerical predictions by RANSE and BEM solvers are validated through comparisons against experimental data for the ship considered in the study. The comparative analysis of untwisted and twisted rudders is carried out by fully-appended ship flow simulations at uniform ship speed and rudder angles between 0 and 20 degree. Numerical results predict comparable manoeuvring capabilities for the alternative layouts, whereas the twisted design allows to mitigate negative pressure peaks observed on the untwisted rudder surface over a range of helm angle