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Biomarkers identification in fibromyalgia syndrome
Get PDFFibromyalgia Syndrome (FMS) is a chronic syndrome characterized by widespread pain. FMS is a collection of other symptoms and overlapping conditions contribute to complicate the diagnosis, the assessment and the treatment. Unknown etiology and none laboratory tests have been appropriately validated for the diagnosis of the disease. The comparison of protein patterns in body fluids of diseased and healthy subjects has the potential to identify new disease-specific biomarkers. Some purine nucleotide metabolism disorders such as myoadenylate deaminase (MAD) deficiency report symptoms similar to those seen in FMS.
In consideration of what described above, we carried out a serum proteomic analysis of FMS patients with respect to control subjects searching potentially useful biomarkers for the disease. In addition, we evaluated serum purine metabolite concentrations in patients affected by FMS and the relationships between their levels and FMS clinical parameters.
Twenty-two females affected by FMS (according to the American College of Rheumatology, 1990) and twenty-two healthy women were recruited as controls for analysis of purine metabolite. Sixteen females FMS and twelve controls were enrolled in the study for the analyses of the proteome. Proteomic analysis was performed by combining two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) and serum purine levels were quantified using reverse phase high performance liquid chromatographic (RP-HPLC).
In our study, using the proteomic approach, we have identified differentially expressed proteins, such as Transthyretin (TTR), Alpha-1 Antitrypsin (A1AT) and Retinol Binding Protein 4 (RBP4). The serum 4 concentrations of these proteins were significantly higher in FMS patients compared with healthy controls. TTR and RBP4 are retinoid transporters, moreover retinoid dysfunction is related to oxidative stress as well as A1AT. These results support the hypothesis that oxidative stress could be implicated in the pathophysiology of FMS.
Moreover, considerably higher serum concentration of inosine, hypoxanthine and xanthine levels (p<0.001) and lower serum adenosine (p<0.05) were detected in the FMS patients when compared to healthy controls. Our data show a negative correlation between adenosine and the Fibromyalgia Impact Questionnaire (FIQ).
Our results suggest that purines, in particular adenosine and inosine, may be involved in pain transmission in fibromyalgia
Complex system simulation: agent-based modeling and system dynamics
Get PDFThis thesis deals with some simulation based approaches used to study software market and software development. Nowadays, the term Software as a Service is everywhere and is described as the future of software. SaaS, also called On-Demand Software, is a software application delivery
model that together with Commercial Open Source Software another pricing approach is slowly gaining ground. Indeed, in recent years, traditional software also called On-Premise software appears overpriced, user's willingness to buy it is decreased and therefore the purchase preferences
are moving from traditional pricing models to new pricing approaches. To study these new pricing tendencies, different models have been realized by using two of the most common numerical techniques: Agent based Modeling and System Dynamics. With agent based modeling two business models have been realized: a model to study the
competition among CRM On-Premise and On Demand vendors and another model to study the competition among CRM On-Demand vendors offering CRM products, with and without source
code availability. Our goals are to propose business models to analyze and study the CRM software market, and to propose a useful tool to forecast business winning strategy and investment and pricing business policies.
Instead, with system dynamics a tool for highlighting how a Global Software Development environment on the Cloud Platform may facilitate GSD with respect to an environment set up On Premise has been realized.
All these models are based on many insights from literature and market analysis. However, concerning the business models, this is the first time that the software market has been modeled using heterogeneous agent model and detailing investment and pricing policies of firms and purchase preferences of customers, and consequently building the model on existing scientific knowledge has not been simple. In addition, lack of experimental data to initialize or validate the models clearly limits the validity of the models, and for this reason the future main objective will be to validate the model using real enterprise data
Assessing sofware quality by micro patterns detection
Get PDFOne of the goals of Software Engineering is to reduce, or at least to try to control, the defectiveness of software systems during the development phase.
Software engineers need to have empirical evidence that software metrics are related to software quality. Unfortunately, software quality is quite an elusive
concept, software being an immaterial entity that cannot be physically measured in traditional ways. In general, software quality means many things.
In software, the narowest sense of product quality is commonly recognized as absence or low incidence of bugs in the product. It is also the most basic meaning of confermance to requirements, because if the software contains too many functional defects, the basic requirement of providing the desired function is not met.
To increase overall customer satisfaction as well as satisfaction toward various quality attributes, the quality attributes must be taken into account in the planning and design of software. To improve quality during development, we need models of the develompment process, and within the process we need to select and deploy specific methods
and approaches, and employ proper tools and technologies. It is necessary to know measures of the characteristics and quality parameters of the development process and its stages, as well as metrics and models to help ensure that the development process is under control to meet the product’s quality objectives. Software quality metrics tend to measure whether software is well structured,
not too simple and not too complex, with cohesive modules that minimize their coupling. Many quality metrics have been proposed for software, depending
also on the paradigm and languages used there are metrics for structured programming, object-oriented programming, aspect-oriented programming, and so on. The use of traditional metrics as quality indicators is very dicult. The Lines of Code (LOC) metric (very related to faults), is dicult to use, you can not say to a team of developers to develop classes by imposing a predefined number of lines
of code. The use of the micro patterns (introduced by Gil and Maman) metrics, that capture concepts of good or bad programming (like anti patterns) can help developers to focus on those classes that belong to categories of micro patterns prone to fault. The relationship between traditional metrics and micro patterns is useful for enabling these new metrics to evaluate software quality. Micro patterns are similar to design patterns, but their characteristic is that they can be identified automatically, and are at a lower level of abstraction with respect to design patterns. This thesis tackles the problem of measuring software quality in Object Oriented (OO) systems by using such novel approaches based on micro patterns that can be a useful metrics in order to measure the quality of software by showing that certain categories of micro patterns are more fault prone than
others, and that the classes that do not correspond to any category of micro patterns are more likely to be faulty. Many empirical studies were performed to
validate empirically CK suite under these two aspects, showing an acceptable correlation between CK metrics values and software fault-proneness and diculty
of maintenance. In OO, micro patterns can help to identify the portions of code that should be
improved (for example those where encapsulation is not respected), and highlight other portions that make up good design practices. The design patterns, defined in the early nineties were an important breakthrough at analysis and design level, but are dicult to be automatically supported at the coding level. There are tools claiming to help finding the usage of design patterns in code, but in practice they are used in a very limited way. On the contrary, micro patterns are defined at coding level, and it is relatively easy to recognize them automatically, thus being able to implement formal conditions on the structure of the class.
Thesis overview The thesis is organized according to this scheme:
• Chapter 2 provides an overview of the concept of software metrics;
• Chapter 3 presents an overview of the design patterns catalogs;
• Chapter 4 discusses the micro patterns catalog using the definitions made
by Gil and Maman;
• Chapter 5 discusses the interpretation of Micro Patterns given by Arcelli
and Maggioni;
• Chapter 6 present the study of the evolution of five particular micro
patterns (anti patterns) in different releases of the Eclipse and NetBeans
systems, and the correlations between anti patterns and faults. The
analysis confirms previous findings regarding the high coverage of micro
patterns onto the system classes, and show that anti patterns not only
represent bad Object Oriented programming practices, but may also be
associated to the production of worse quality software, since they present
a significantly enhanced fault proneness.
• Chapter 7 present a study that aims to show, through empirical studies of
open source software systems, which categories of micro patterns are
more correlated to faults. Gil and Maman demonstrated, and subsequent
studies confirmed, that 75% of the classes of a software system are
covered by micro patterns. In this chapter is also analyzed the relationship
between faults and the remaining 25% of classes that do not match with
any micro pattern. We found that these classes are more likely to be faultprone
than the others. We also studied the correlation among all the micro
patterns of the catalog, in order to verify the existence of relationships
between them.
• Chapter 8 present a study on micro patterns in different releases of two software systems developed with Object Oriented technologies and Agile process. In this chapter we present some empirical results on two case studies of systems devel- oped with Agile methodologies, and compare them to previous results obtained for non Agile systems. In particular we have verified that the distribution of micro patterns in a software system developed using Agile methodologies does not differ from the distribution
studied in other systems, and that the micro patterns fault-proneness is about the same. We also analyzed how the distribution of micro patterns changes in different releases of the same software system. We demonstrate that there is a relationship between the number of faults and
the classes that do not match with any micro patterns. We found that these classes are more likely to be fault-prone than the others even in software
developed with Agile methodologies
• Chapter 9 present the Java tool used in order to extract from the source
code the informations about micro patterns distributions.
• Chapter 10 discusses the related works in the field
Dynamic deployment of applications in wireless sensor networks
Get PDFOver the past decades, the progress inWirelss Sensor Network (WSN) technology, both in terms of processing capability and energy consumption reduction, has evolved WSNs into complex systems that can gather information about the monitored environment and make prompt and intelligent decisions. In the beginning, military applications drove the research and development of WSNs, with large-scale acoustic systems for underwater surveillance, radar systems
for the collection of data on air targets, and Unattended Ground Sensor (UGS) systems for ground target detection. Typical civil WSNs are basically not complex monitoring systems, whose applications encompass environment and habitat monitoring, infrastructure security and
terror threat alerts, industrial sensing for machine health monitoring, and traffic control. In these WSNs, sensors gather the required information, mostly according to a fixed temporal schedule, and send it to the sink, which interfaces with a server or a computer. Only at this point data from sensors can be processed, before being stored.
Recent advances in Micro-Eletro-Mechanical Systems (MEMS), low power transceivers and microprocessor dimensions have led to cost effective tiny sensor devices that combine sensing with computation, storage and communication. These developments have contributed to the efforts on interfacing WSNs with other technologies, enabling them to be one of the pillars of the Internet of Things (IoT) paradigm. In this context, WSNs take a key role in application
areas such as domotics, assisted living, e-health, enhanced learning automation and industrial manufacturing logistics, business/process management, and intelligent transportation of people and goods. In doing so, a horizontal ambient intelligent infrastructure is made possible, wherein
the sensing, computing and communicating tasks can be completed using programmable middleware that enables quick deployment of different applications and services.
One of the major issues with WSNs is the energy scarcity, due to the fact that sensors are mainly battery powered. In several cases, nodes are deployed in hostile or unpractical environments, such as underground or underwater, where replacing battery could be an unfeasible operation. Therefore, extending the network lifetime is a crucial concern. Lifetime improvement has been approached by many recent studies, from different points of view, including
node deployment, routing schemes, and data aggregation Recently, with the consistent increase in WSN application complexity, the way distributed applications are deployed in WSNs is another important component that affects the network lifetime. For instance, incorrect execution of data processing in some nodes or the transmission
of big amounts of data with low entropy in some nodes could heavily deplete battery energy without any benefit. Indeed, application tasks are usually assigned statically to WSN nodes, which is an approach in contrast with the dynamic nature of future WSNs, where nodes frequently join and leave the network and applications change over the time. This brings to issue talked in this thesis, which is defined as follows. Dynamic deployment of distributed applications in WSNs: given the requirements of WSN
applications, mostly in terms of execution time and data processing, the optimal allocation of tasks among the nodes should be identified so as to reach the application target and to satisfy the requirements while optimizing the network performance in terms of network lifetime. This
issue should be continuously addressed to dynamically adapt the system to changes in terms of application requirements and network topology
Leg vein pressure pulser (LVPP): a mechatronic device for spinal cord injured patient standing in for the ineffectiveness of paralyzed leg muscles to pump blood from leg veins towards heart
Get PDFParaplegic subject often experience an impairment of the cardiovascular function. One of the most important factors in the occurrence of this situation is the drastic reduction in venous return from the muscle at rest, due to the absence of the function of muscle pump that is present in the able-bodied subjects. It is reasonable to assume that an external mechanical force applied on the lower limbs of paraplegic subjects might produce a positive effect on cardiovascular condition. Accordingly, the research aimed to identify and develop a robotic device to restore the cardiovascular function in paraplegics.
To test this hypothesis we performed two experimental studies involving healthy subjects where two automatic robotic able to apply an ascendant external pressure to lower limbs were tested. Hemodynamic response was monitored beat-by-beat by means of impedance cardiography and Doppler ultrasound was used to measure cardiac volumes. Results show that the application of robotic mechanical actuators pneumatic is able to generate cycles of compression and decompression on venous structures of the lower limbs similar to what normally happens in the skeletal muscle when subjects are walking. Especially when actuators simulated muscle pattern activation similar to mechanism of walking we were able to further increase cardiac output and end diastolic volume. In conclusion our preliminary finding suggest that is possible to compensate partially the lack of venous return in spinal cord injury population thus increasing the quality of life, reducing the risk of cardiovascular disease and then extend their life expectancy
Organized crime and corruption: a theoretical and empirical analysis
Get PDFNowadays a large part of academic literature and international organizations largely and increasingly recognize that corruption acts as a major impediment to growth. However, there are still some doubts and large room to further investigate the economic consequences of corruption. Very recently, the most important international agency focused on fighting corruption (Transparency International) has underlined the importance to better understand the links between corruption and organized crime and their combined effects on economic growth. The purpose of our research is to further investigate these issues, both theoretically and empirically. More precisely, thinking about the phenomena of corruption and organized crime, the questions we try to answer through our research are: i) is there some relationship between the two phenomena? ii) if yes, can we explain this relationship using a theoretical model? iii) can we find appropriate proxies and indexes of organized crime and corruption in order to empirically test the theoretical model described in point ii)? and moreover: iv) is there some possibility to solve the doubts about the economic effects of corruption taking into account the relationship between the two phenomena? These are the main questions which lead our research and that we try to answer in this dissertation. Clearly, in order to better understand these questions and related answers, a detailed literature review of theoretical and empirical studies on corruption, crime and organized crime will be presented (Chapter 1). Then, we develop a simple theoretical framework which analyses the effects of the two phenomena on the economy and empirically test the effects of the two illegal activities on the economic growth of Italian regions (Chapter 2 and Chapter 3 respectively)
La cooperazione tra pubbliche amministrazioni nell'amministrazione digitale. Lo sportello unico telematico
Get PDFThe thesis is part of the studies on cd "Tele-administration", meaning the possibility and necessity
of the use of computer tools in the internal and external activities involving the Public Authorities. This work, which feeds of production and scientific achievements so far achieved, the current historical context technological, relates to the research and analysis solutions to simplify the administrative and consequently efficiency and economy in 'agere’ of PP.AA. The administrative activity is in fact characterized increasingly complulsory use of telematic tools, both internally between offices of the same PA, both in external relations with the citizen / business, both in relations between the different public administrations
The new information technologies transform the manner and timing of administration and delivery of public services, allowing the safe simplification of the relationships between multiple administrations and, consequently, improved relations with the citizens of the latter.
The Technoligies Information and Communication (ICT) must also deal with the traditional tools used to date by public administrations which require methods and timing of organization and functioning significantly slower. In this context, the Public Authorities need to develop ways
appropriate and necessary to metabolize the potential of the technological evolution. The research analyzes, studies and verifies in particular the legal issues underlying the use of the Single Desk Electronic, art. 10 of the Digital Administration Code. It has been examined in the first instance, on what legal rules are applicable to the administrative activities computerized. A strategy for e-government, which is a direct application of the One-Stop Electronic, compatible with the idea of participatory democracy presupposes an advanced legislation on the front of the cd web-usability: the enhancement of diffusion and facilities in access, even by weak subjects, new
technology is the prerequisite for an effective and democratic electronic government. That is why we must consider the OSS no longer reserved for companies, but also to the City citizen. If the City citizen can communicate with the AP via computer with their own tools is an advantage, but not abandoned the citizen in the digital divide, which must be made available to traditional
banking branches manned by dedicated employee who will activate your account for the new computerized procedures and inform you of the ITER practice.
It was therefore analyzed the relationship between the online reorganization of public administrations and the quality of citizens' rights-users of public services, the relationship between citizens and government-owned enterprises and the two transverse profiles involving the balance between the efficiency of the services and the guarantee of the right to privacy and the problems of
the spread of access to new technologies, including by vulnerable and disadvantaged.
As for the administrations involved, it is necessary to distinguish the role of the administration
proceeding from the outer and must be solved the problem of information cooperation between them for the purpose of electronic management of the proceedings necessary to secure the enactment of the final measure. Even in the context of public administrations there is the problem of the digital divide, it must be remedied by providing the necessary technical and organizational support in accordance with the principle of subsidiarity, without prejudice to the substantial administrative powers that the law gives to even the smallest municipality. The doctoral thesis research on the subject, also allows you to depict the current situation of the Single Desk analyzing the relations with the citizens / businesses, and verifying whether and how these tools have led to the improvement of the aforementioned relationships.
We propose to analyze the current situation at the point of simplification of administrative activity with particular reference to the Single Desk Telematic after about 10 years after approval of DPR 447/1998 on the OSS.
In addition, the research on behalf of the "state of the art" of the legislation on the electronic OSS. There is no doubt that the legislature also and especially with the news of 2005 (Laws. 15 and n. 80) moved to a twofold direction in the attempt, on the one hand, to ensure openness and transparency of the public administration by ensuring forms of participation in the administration, especially with the exercise of the right of access referred to in Chapter V of the Law 241/1990 (to combine with the protection of privacy of Legislative Decree no. 196/2003), and by ' another in an effort to streamline and simplify the administrative, procedural participatory forms such as providing conference services (including the use of telematics, Art. 14, paragraph 5 bis of Law 241/1990).
In an effort to simplify, streamline and accelerate the administrative activities in order to ensure a better and faster collaboration between public administrations, which result in a better and faster service delivery to the citizen / business, the legislature has provided the One-Stop of Industry by establishing, first with the Legislative Decree no. 112/1998 and with the dpR 447/1998 that information on the One Stop Shop for Productive Activities should be promoted and made
knowable even electronically, and then with the Legislative Decree no. 82/2005 (Government Code) that the One Stop Shop for Business production must be carried out on computer and must povide its services to users in electronically.
The argument in this regard, it is proposed to account for the problems that determine the slowness nd inefficiency of the public administration, implementing thus the Digital Administration Code.
The efficiency and speed of action of PA can in fact be achieved not only with the dematerialization
of paper, which clogs the gears of the functioning of the administration, but also with the
digitization of the same administrative activities, with the possibility of submit questions computer,
and with the necessity that the same administrative procedure in all its stages is carried out
electronically with the adoption of a measure itself telematico.
However a step towards such a solution was offered by the OSS Telematic that seems to be imbued
with the principles that have been highlighted above and which represent the most advanced
explanation of e-government.
That said, the study verifies the expandability of the Single Desk Electronic, meaning to see if it is
the main form of overcoming all the traditional red tape, and then determine whether it should be
used as a tool for all activities of the PA generally understood, not only for productive activities, but
also for the construction industry, for example, and from there the possibilities would become
almost endless
Possibile ruolo dei recettori PPARα in modelli animali di ansia e depressione
Get PDFAlpha-type peroxisome proliferator-activated nuclear receptors (PPARα), which regulate many important physiological responses such as lipid metabolism, energy balance and inflammation, are the endogenous target of the fatty acid amides oleoylethanolamide (OEA) and palmitoylethanolamide (PEA). Like the endogenous cannabinoid anandamide (AEA), OEA and PEA are synthetized on demand and are primarily degraded by fatty acid amide hydrolase (FAAH), but do not show affinity for cannabinoid receptors. On the other hand, AEA and other endocannabinoids such as noladin ether and virodhamine, show binding affinity for PPARα receptors and increase their transcriptional activity. Endocannabinoids and PPAR agonists share targets and functions in both the brain and the periphery. Since the endocannabinoid system (ECBs) is involved in several psychiatric disorders like schizophrenia, bipolar disorder and depression, this thesis investigated the role of involvement of OEA and PEA in depression and other disorders. In particular this work characterized the behavioral profiles of OEA and PEA in the tail flick test, elevated plus maze and forced swimming test (FST) in adult male Sprague Dawley rats. For all drugs used in this study, motor activity test was conducted to select doses avoid of any aspecific effect on animal behaviour. Both compounds did not affect the antinociception response of rats in the tail flick test and show neither anxiolytic nor anxiogenic-like effects in the elevated plus maze test. More intriguingly the sub-chronic treatment with OEA (2.5 mg/kg and 5 mg/kg) and PEA (1 mg/kg and 2 mg/kg) significantly decreased the duration of immobility and increased swimming with respect to control rats. The PPARα antagonist MK886, at a dose (1 mg/kg, i.p) that by itself did not show any effect in the FST, fully reversed the effects of OEA and PEA thus confirming the direct involvement of PPARα in the observed antidepressant-like effects. Moreover, the CB1r antagonist/inverse agonist rimonabant, likewise MK886, antagonized the antidepressant-like effect of OEA and PEA, suggesting a possible involvement of the endocannabinoid system. Immunohistochemical staining was conducted on brains of animals treated with OEA and PEA before performing the FST, to evaluate molecular and morphological changes in the hippocampus by studying the expression of glutamic acid decarboxylase (GAD67) and microtubule-associated protein-2 (MAP-2), which are known to be involved in several psychiatric and neurodegenerative diseases. These two markers are modified by drug treatments, in line with behavioral data supporting antidepressant-like effects of OEA and PEA. PPAR also mediate the deactivation (phosphorylation) of nicotinic acetylcholine receptors (nAChRs) which are widely expressed (particularly the α4β2 and 7 nAChR) in brain areas involved in analgesia, anxiety, depression, reward and cognitive functions. Thus the possibility of a link between the cholinergic system, known to be modulated by ECBs, and PPAR was investigated in the FST by using the specific 7 nAChRs agonist PNU282987 (PNU, 3 mg/kg, i.p), alone and in combination with MK886. In support to this, PNU elicits antidepressant-like effect that are reversed by MK886. Although the mechanisms through which OEA and PEA exert antidepressant –like effects are still to be clarified, the present study suggests that these compounds could have a role in the neurobiology of psychiatric diseases and particularly in depression
Il viceré Des Hayes e il governo del Regnum Sardiniae
Get PDFThe research aspires to realize the first monographic study of political and administrative activity of the Earl Vittorio Lodovico d’Hallot Des Hayes, Viceroy of Savoy in Sardinia from 1767 to 1771. This was the crucial moment in the policy of reformation for the Island, starting with Gian
Battista Lorenzo Bogino, the Minister for Sardinian Affairs (1759-1773), intent upon increasing bureaucracy on the Island and realizing an administrative centralization. Reconstructing the political activity of Des Hayes allows the controversial studies of this reform politics of the Savoy household to be revised. This required new investigation of the documents regarding these years, correspondence, reports and essays, to realize an efficient wider framework. Des Hayes participated in debates in Cagliari and Turin about reform projects for the Island,
disclosing their real efficiency, the modality of their application, and also class involvement, namely nobility and clergy (diocesan and regular) and their feelings about this. First of all, analysis of discussions within the councils reveals that Cagliari was less marginal than what has often considered by historians: Sardinian bureaucrats took an active part in these open discussions, suggesting many concrete and solid state interventions to face political, administrative, economic, feudal, ecclesiastical and cultural problems. Secondly, it results that the viceroy pursued a clear intent of reformation, but with extreme prudence. He found it essential to reconstitute warily, not upset drastically. Therefore, his approach
was pragmatic: every reform had to be based on field work, the only way to remove preconceptions and to avoid intervention resulting from rash determination. For this reason, Des Hayes seem to be viceroy who had political freedom, supporting or declining the proposals developed in Cagliari and in Turin after an accurate analysis of their feasibility
Malnutrizione proteico-energetica, sarcopenia e disidratazione nella popolazione senile sana e affetta da patologie
Get PDFBackground: Ageing is correlated with nutritional status imbalance. Protein Energy-Malnutrition (PEM) can lead to hydration balance impairment and sarcopenia, a loss of muscle mass. Sarcopenia syndrome can be worsened by the excess of fat mass leading to sarcopenic obesity. These conditions are associated with an increasing risk of morbidity, mortality and of cognitive, functional and psychological decline. Screening analysis features an important tool to prevent negative outcomes. The most accurate body composition assessment techniques, such as Computed Tomography, Magnetic Resonance Imaging and Dual energy X-ray Absorptiometry (DXA) are weakly invasive and not easily accessible to investigators because of their high operational costs. Among the other techniques (anthropometry and impedance), Bioelectrical Impedance Vector Analysis (BIVA) is easy to use, inexpensive, non invasive and can be used in biomedical field and clinical practice to evaluate hydration and nutritional status. However, its validity in assessing body composition was lacking.
Objective: Ascertaining the accuracy of BIVA to assess body composition variations and validating an analytic variant, specific BIVA. Classic and specific BIVA will be applied in different samples of elderly subjects in order to evaluate body composition variations in relation to psycho-functional status and health condition.
Design: Several samples of healthy (658 subjects, 60 y or older) and pathological elderly (227 subjects, 65 y or older, with Alzheimer’s disease or type 2 diabetes mellitus), and a sample of healthy adults from U.S. (1594 subjects, 21-49 y) were considered (NHANES 2003-2004). Six anthropometric measurements were taken (height, weight, calf, waist and arm circumferences, body mass index (BMI)). Classic BIVA and the new variant (specific BIVA), that adjust bioelectrical values for body geometry, were applied. DXA was used as the reference method. Classic and specific BIVA results were compared by Receiver Operating Curve (ROC curve) analysis and by a probit multiple-regression.
The psycho-functional status was assessed by Mini Mental State Examination (MMSE), Geriatric Depression Scale (GDS), Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL). Muscle strength was measured by the Hand Grip Strength (HGS) and Short Physical Performance Battery (SPPB) tests.
Results: Classic BIVA distinguished individuals with different amounts of fat and fat-free mass, according to DXA, but not those with different proportions of fat mass (FMDXA%). Specific bioelectrical values detected changes in body composition, resulting significantly more accurate than classic BIVA in evaluating FMDXA% (ROC areas: 0.84 - 0.92 and 0.49 - 0.61 respectively; p=0.002). The evaluation of extracellular water/intracellular water ratio was accurate (ROC areas between 0.83 and 0.96) and similarly performed by the two procedures (p=0.829). Classic and specific BIVA detected significant differences between sarcopenic and nonsarcopenic individuals. Moreover, specific BIVA recognized bioelectrical differences between sarcopenic and sarcopenic obese men. Classic BIVA showed that patients with Alzheimer's disease have a worse psycho-functional and nutritional status compared to a control group. Patients with diabetes showed greater body dimensions and a reduced muscular area, compared to healthy controls. Specific BIVA showed no association with muscular strength tests. The specific bioelectrical standards for the Italian elderly population have been proposed.
Conclusions: Specific BIVA proved to be an accurate technique and a promising tool to assess age-related changes in body composition. Older patients with sarcopenia, sarcopenic obesity, Alzheimer’s disease, and type 2 diabetes were characterized by peculiar bioelectrical patterns, which can be related to their body composition characteristics. The newly proposed bioelectrical standards for the Italian elderly population allow the application of classic and specific BIVA in the geriatric routine