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Biomedical subjects

S Siboni

Publications and source records attributed to S Siboni.

9 recordsLinked to original sources
PubMed2006

Rare bleeding disorders.

Deficiencies of coagulation factors other than factor VIII and factor IX (afibrinogenemia, FII, FV, FV+FVIII, FVII, FX, FXI, FXIII) that cause bleeding disorders (RBDs) are inherited as autosomal recessive traits and are rare, with prevalences in the general population varying between 1 in 500,000 and 1 in 2 million for the homozygous forms. As a consequence of the rarity of these deficiencies, the type and severity of bleeding symptoms, the underlying molecular defects, and the actual management of bleeding episodes are not as well established as for hemophilia A and B. The study of the genetic basis of these disorders could represent an important tool for prevention through prenatal diagnosis. Treatment of patients with RBDs during bleeding episodes or surgery is a challenge because of the lack of experience and the paucity of data. For some deficiency factor concentrates are still non available and severe complications can occur. These complications can be minimized by assessment of risks of bleeding and thrombosis, use of haemostatic means other than blood components or no therapy at all. The RBDs pose a problem for guideline writers because there are no suitable clinical trials to supply good evidence for how these people are best treated. The lack of adequate information on clinical manifestations, treatment and genetic basis of RBDs could be improved by the collection of data in an International Database (http://www.rbdd.org), linkable to others previously published. This could be a useful tool to fill the gap between clinical data and clinical practice. This article reviews the genetic basis of RBDs, problems and complications of treatment, problems in the preparation of suitable guidelines for treatment and the future perspectives of the International Registry on RBDs.

Blood Coagulation Disorders, Inherited↗
PubMed2005

Molecular connectivity methods for the characterization of surface energetics of liquids and polymers.

In the topological approach to structure-property relationships, the molecular structure is described in terms of appropriate weighted graphs to which suitable topological parameters, usually known as molecular connectivity indices, can be associated. Molecular connectivity indices are here applied to the prediction of surface free energy and Good-van Oss-Chaudhury acid-base components of organic compounds. To this aim, some quantitative structure-property relationships (QSPRs) are determined, involving both topological indices and group indicator variables of the customary functional group theory. The semiempirical models obtained to appear satisfactory and show significant advantages with respect to the models based on the purely functional group approach.

Journal Article↗
PubMed2004

The solid surface free energy calculation. I. In defense of the multicomponent approach.

The acid-base approach to the calculation of solid surface free energy and liquid-liquid interfacial tensions is a practical example of application of correlation analysis, and thus it is an approximate approach. In these limits, and provided that wide and well-obtained sets of contact angles or interfacial tension data are used for their computation, surface tension components can be considered as material properties. Although their numerical value depends on the characteristics of the chosen reference material, their chemical meaning is independent on the selected scale. Contact angles contain accessible information about intermolecular forces; using surface tension component (STC) acid-base theory, one can extract this information only making very careful use of the mathematical apparatus of correlation analysis. The specific mathematical methods used to obtain these results are illustrated by using as an example a base of data obtained by the supporters of the equation-of-state theory (EQS). The achievements are appreciably good and the agreement between STC and EQS is discussed.

Journal Article↗
PubMed2004

The solid surface free energy calculation; II. The limits of the Zisman and of the "equation-of-state" approaches.

This paper follows the "defense" of the Good-van Oss-Chaudhury (GvOC) acid-base approach made in Part I and carries out a detailed analysis of the Zisman critical surface energy and, mainly, of the Neumann equation-of-state (EQS) theory. The analysis is made on both a "practical" and a theoretical basis, trying to highlight the acceptable fitting results of axisymmetric drop shape analysis (ADSA) methods and their independence of the assumed thermodynamic foundations of EQS. Some new and original criticisms of the EQS approach are raised and it is shown that other purely semiempirical models, represented by different fitting equations with the same number of parameters, can represent the data measured by ADSA method with the same goodness as EQS. The equation of state appears as one of many semiempirical approaches for the evaluation of surface free energy of solids. Independent of the previous analysis, the criteria used in ADSA measurements are evaluated and some comments made on them.

Journal Article↗
PubMed2004

Comparison of attitudes towards prenatal diagnosis and termination of pregnancy for haemophilia in Iran and Italy.

Prenatal diagnosis (PND) is an important issue in the comprehensive care of haemophiliacs. As a consequence of technological progress made in the field of PND, the early detection of an affected fetus provides the expectant couple with a chance to terminate pregnancy. This study was undertaken to assess the attitudes of two different haemophilic populations in Iran and Italy towards PND and termination of pregnancy. This study series included 59 Iranians (38 haemophilia A patients and 21 mothers) and 50 Italians (27 haemophilia A patients, 16 mothers and seven fathers). All the 109 participants received a questionnaire including demographic characteristics and evaluating the psychological effects stemming from PND and termination of pregnancy. Approximately 84.7% of the Iranians and 35.4% of the Italians were not familiar with the possibilities afforded by PND for haemophilia (P < 0.001). Termination of pregnancy appeared to be accepted by 58.2% of the Iranian and 16.7% of the Italian participants (P < 0.001). The greater rate of acceptability of abortion in Iranians may be due to differences in the quality of patient care in the two countries.

Abortion, Induced↗
PubMed2003

[Modern algorithm for treating pudendal neuralgia: 212 cases and 104 decompressions].

Clinical signs and symptoms of the pudendal neuralgia are very rich, with a great individual variability. The clinical diagnosis is difficult. It is confirmed or invalidated by the electrophysiologicals tests. Since October 1998 patient selection has been possible using a diagnosis score. Over a four-year period, the diagnosis of pudendal neuralgia was confirmed by electrophysiological investigations in 212 subjects. We rejected 12 patients because of a radiculo-medullary organic etiology. We only describe here cases of women with a peripheral pudendal nerve injury (200 patients). Thirty-eight neuropathies free of canal symptoms (obstetrical, post-traumatic...) were treated by infiltration therapy. The study of a total of 162 canal syndromes showed prevalent injury at the sacro-spino-tuberal ligamental grip which was observed in 68% of the cases, compared to the Alcock canal which was present in only 20% of the cases. One hundred four of these patients underwent surgical decompression via a trans-ischio-rectal approach after negative results of the infiltration therapy. We report here the surgical methodology, the post-op follow-up and the results, which appear quite successful: after one year 86% of the subjects are symptom-free or with a significant reduction of pain.

Adult↗
PubMed1997

Some Reflections on Acid-Base Solid Surface Free Energy Theories

This paper considers the correctness of the application of Good-van Oss theory (vOGT) to the calculation of acid-base components of solid surface free energies. Theory equations are written in a matrix form, and their application is analyzed particularly from a mathematical point of view. A calculation procedure similar to the approach used for other scales of acid-base strength is suggested to obtain in a straightforward manner the necessary material coefficients. The chemical consequences of these considerations are also discussed. The acceptability of current experimental literature data and the validity of the calculations obtained from them by the proposed method are considered, showing the origin of some inconsistencies in current results. Some general considerations regarding the difficulties commonly encountered in the application of vOGT are also discussed, and it is shown that they can be rationalized or eliminated with more acid solvents being included in the solvent set and the properties of the reference solvent being correctly chosen. The difficulties encountered in correctly expressing the acid properties of some polymers are closely examined. Finally, some indications are given of the future possible developments of vOGT. Copyright 1997 Academic Press. Copyright 1997Academic Press

Journal Article↗