Dynamic balance assessment during gait in children with Down and Prader-Willi syndromes using inertial sensors.

Down (DS) and Prader-Willi (PWS) syndromes are chromosomal disorders both characterized by obesity, ligament laxity, and hypotonia, the latter associated with gait instability. Although these shared features may justify a common rehabilitation approach, evidence exists that adults with DS and PWS adopt different postural and walking strategies. The development of an instrumented protocol able to describe these strategies and quantify patients' gait stability in the current clinical routine would be of great benefit for health professionals, allowing them to design personalized rehabilitation programs. This is particularly true for children with DS and PWS, where motor development is dramatically constrained by severe hypotonia and muscle weakness. The aim of this study was, thus, to propose an instrumented protocol, integrated with the clinical routine and based on the use of wearable inertial sensors, to assess gait stability in DS and PWS children. Fifteen children with DS, 11 children with PWS, and 12 typically developing children (CG) were involved in the study. Participants performed a 10-meter walking test while wearing four inertial sensors located at pelvis, sternum, and both distal tibiae levels. Spatiotemporal parameters (walking speed, stride frequency, and stride length) and a set of indices related to gait symmetry and upper-body stability (Root Mean Square, Attenuation Coefficient and Improved Harmonic Ratio) were estimated from pelvis and sternum accelerations. The Gross Motor Functional Measures (GMFM-88) and Intelligence Quotient (IQ Wechsler) were also assessed for each patient. A correlation analysis among the GMFM-88 and IQ scales and the estimated parameters was then performed. Children with DS and PWS exhibit reduced gait symmetry and higher accelerations at pelvis level than CG. While these accelerations are attenuated by about 40% at sternum level in CG and DS, PWS children display significant smaller attenuations, thus reporting reduced gait stability, most likely due to their typical "Trendelenburg gait". Significant correlations were found between the estimated parameters and the GMFM-88 scale when considering the whole PWS and DS group and the PWS group alone. These results promote the adoption of wearable technology in clinical routines to monitor gait patterns in children with DS and PWS: the proposed protocol allows to markedly characterize patient-specific motor limitations even when clinical assessment scores provide similar results in terms of pathology severity. This protocol could be adopted to support health professionals in designing personalized treatments that, in turn, could help improving patients' quality of life in terms of both physical and social perspectives.

Molecular-based upconversion in homo/heterogeneous liquids and in micro/nanostructured solid materials.

Radiation upconversion can be an elegant and efficient strategy to minimize waste in energy harvesting and storage processes. The upconversion based on triplet-triplet annihilation processes of molecular dyes is a very versatile approach, but it requires a systematic photophysical characterization of the systems to optimize the upconversion yields and develop materials for technological applications. This paper represents an overview of the work carried out in our laboratories for the study and characterization of a molecular dye pair, 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(ii) (PtOEP) and 1,3,6,8-tetraphenylpyrene (TPPy), suitable as the sensitizer and emitter, respectively, in a triplet-triplet annihilation based upconversion process. The investigation has been carried out in various media with increasing complexity. First, we used the dye pair to characterize the UC-efficiencies in homogeneous solvents of different viscosities and in oil-in-water microemulsions; then we explored the possibility to achieve upconversion in solid materials, like nanostructured silica matrices and liquid filled microcapsules. The possibility to achieve upconversion emission even in confined and rigid media has been confirmed and can inspire further applications of the process.

A two excited state model to explain the peculiar photobehaviour of a flexible quadrupolar D-π-D anthracene derivative.

The peculiar photobehaviour of a symmetrical arylenevinylene anthracene derivative bearing mild electron donors (alkoxy groups) at the sides of its structure has been fully comprehended through this study. An investigation into the effect of solvent polarity and temperature on the stationary fluorescence spectrum allowed a clear dual emission to be revealed. A further valuable insight was obtained, thanks to the employment of ultrafast spectroscopies. Fluorescence up-conversion measurements and the Time Resolved Area Normalised Spectra analysis provided a clear-cut proof of the presence of two distinct fluorescent states ((1)A* and (1)B*), with (1)A* being responsible for the steady-state emission in highly polar and viscous media. Femtosecond transient absorption spectra were acquired in several organic solvents of different polarity and viscosity. Interestingly, the lifetime of (1)A* was found to be dependent on solvent viscosity whereas the lifetime of (1)B* showed a trend which matches the change in solvent polarity. Indeed, the Density functional theory calculations predicted a structural rearrangement in the fully relaxed lowest excited singlet state. The (1)A* → (1)B* transition is thus likely accompanied by large amplitude motions of the molecular structure, with the (1)B* state also exhibiting a small intramolecular charge transfer character. The investigated flexible quadrupolar D-π-D system arouses therefore great interest as a novel material for applications in organic electronics and photonics.

Twisting in the excited state of an N-methylpyridinium fluorescent dye modulated by nano-heterogeneous micellar systems.

A push-pull N-methylpyridinium fluorescent dye with a pyrenyl group as the electron-donor portion was investigated within the nano-heterogeneous media provided by some micellar systems. The molecule was studied by stationary and time-resolved spectroscopic techniques in spherical micellar solutions and viscoelastic hydrogels, in order to throw light on the role played by twisting in its excited state deactivation. As proven by femtosecond fluorescence up-conversion and transient absorption experiments, the excited state dynamics of the molecule is ruled by charge transfer and twisting processes, which, from the locally excited (LE) state initially populated upon excitation, progressively lead to twisted (TICT) and planar (PICT) intramolecular charge transfer states. The inclusion within micellar aggregates was found to slow down and/or limit the rotation of the molecule with respect to what had previously been observed in water, while its confinement within the hydrophobic domains of the gel matrixes prevents any molecular torsion. The increasing viscosity of the medium, when passing from water to micellar systems, implies that the detected steady-state fluorescence comes from an excited state which is not fully relaxed, as is the case with the TICT state in micelles or the LE state in hydrogels, where the detected emission changes its usual orange colour to yellow.

Unexpected multiple activated steps in the excited state decay of some bis(phenylethynyl)-fluorenes and -anthracenes.

The temperature effect on the photophysical parameters of four acetylene-derivatives [bis(phenylethynyl)-anthracenes and -fluorenes with substituents of different electron acceptor efficiencies] has been investigated by absorption and emission spectroscopy, using stationary and pulsed (ns/fs resolution) techniques. The nature of the central nucleus (anthracene or fluorene) and the peripheral electron-withdrawing group (nitro or formyl) strongly affect the deactivation of the excited states of these push-pull molecules. In some cases the study evidenced an interesting role of two activated steps in the deactivation of the excited singlet state, namely an activated inter-system crossing to an upper triplet state of n,π* nature (previously hypothesized on the basis of TD-DFT calculations) and a sort of activated internal conversion, discussed also on the basis of maximum entropy method analysis of the fluorescence decay data. Nicely, an efficient ISC was found for the fluorene-derivatives where small energy gaps between S1 (π,π*) and Tn (n,π*) states had been calculated while no activated ISC was evidenced in the case of anthryl-derivatives where higher S1-Tn energy gaps are expected. A peculiar temperature effect for a fluorene-derivative was pointed out and also explained on the basis of quantum-mechanical calculations at the DFT level taking into account the solvation effects by means of the conductor-like polarizable continuum model CPCM. The presence of dual emission, at first evidenced by a shoulder in the emission spectrum of the fluorene-derivative featuring a peripheral formyl group in dichloromethane at low temperatures, was nicely confirmed by femtosecond up-conversion measurements at room temperature.

Doxycycline and oxytetracycline loading of a zwitterionic amphoteric surfactant-gel and their controlled release.

Oxytetracycline (OX) and doxycycline (DX) are antibiotics belonging to the family of tetracyclines. We present a UV-Visible steady state and time-resolved experimental study of OX and DX and their biologically active Mg(2+) complexes loaded within a hydrogel matrix. Hydrogels are a three dimensional network of worm-like micelles, mutually intertwined, forming a pattern of hydrophobic domains and water pools. We resorted to a hydrogel, made of a zwitterionic N-oxide surfactant (p-dodecyloxybenzyldimethylamine N-oxide, pDoAO), which showed promising features as a drug vehicle. The spectral and photophysical properties of the drugs are significantly altered by the inclusion in the hydrophobic domains of the gel and these variations are indicators of the permeation ratio of the drug in between the micelles forming the gel network. We thus get a clear picture of the distribution of the drug molecules and metal chelates into the two different kinds of environment, where the hydrophobic domains are also able to cause a gel-induced deprotonation of these two drugs. Furthermore, the amphoteric nature of the surfactant is responsible for its peculiar acid-base behaviour: under acidic pH conditions, the surfactant gets protonated and the stability of the gel network is damaged. This feature can be thus exploited for the pH controlled release of the tetracycline drugs.

The Bonfils fiberscope: a clinical evaluation of its learning curve and efficacy in difficult airway management.

BACKGROUND: This study evaluated the use of the Bonfils fiberscope by analyzing its learning curve, efficacy and safety during airway management. METHODS: This was a prospective observational study where five anesthetists, with differing levels of experience, were asked to use the Bonfils rigid fiberscope (Karl Storz) for a six-month period. They used the scope when performing endotracheal intubations in patients undergoing general anesthesia. The patients were excluded if various clinical indicators predicted that they might be difficult to intubate. The patient's head was kept in the neutral position to simulate the intubation of a trauma patient. Direct laryngoscopy with a Macintosh blade was performed to assign a Cormack and Lehane grade prior to attempting laryngoscopy with the Bonfils fiberscope. After intubating the patient with the Bonfils fiberscope, intubation time and any complications or failures noted after the procedure were recorded. RESULTS: The study included 216 patients, three of which were failed intubations. No complications occurred during the study period. The median intubation time was 21.4 s. The learning curve improved significantly after 20 intubations (P<0.05) and was affected by the operator's experience and aptitude with endoscopic viewing. Seventeen patients were deemed to have "unpredicted" difficult airways: 15 subjects with a Cormack grade 3 (6.9%) and two subjects with a Cormack 4 (0.9%). Median time to intubation in subjects with a Cormack <3 was 16 s (95% CI=10-29 s), and in subjects with a Cormack ≥3, it was 15 s (CI 95%=15-18 s) with P=0.703. CONCLUSION: The Bonfils fiberscope is an efficient, easy to use and safe device for endotracheal intubation.

Influence of patients' representations and beliefs about diabetes and its treatment on their adherence to therapy.

Research in the last 25 years has shown that diabetic patients' adhesion to medical advice is a multi-factor phenomenon. Most recent research has focused on a patient-centred approach, on the representations that the patient has with respect to medicine, health and disease (with particular regard to the perceived self-efficiency in managing the disease, trust in conventional medicine, treatment, drugs, etc) and on the level of agreement between the patient's representations and those of the health care provider. These representations can potentially act as barriers/facilitators on patients' adhesion to treatment; the best adherence can only be obtained if the real needs of the patient are met, matching therapy with his/her representations and expectations, and acknowledging the constraints that everyday life puts on the individual. The indication is therefore to avoid exclusively considering the physical burdens of the disease, while ignoring the personal and social significance of the experience that the patient is having. It will take time for this to become routine in health care, since it requires a complex change from a traditional, bio-medical approach to an integrated bio-psycho-social approach. The aim of this review is to show how those disease representations of diabetes, and the treatment having considerable impact on patients' adhesion, are being considered in recent literature, and how this nonetheless still constitutes a little explored aspect in medical consultation and research.

Personality variables and compliance with insulin therapy in Type 2 diabetic subjects.

Forty-five diabetic patients were studied to evaluate adaptation and coping strategies. The authors have also analysed personality traits mainly to study different behaviour in compliance conduct. The results revealed an important psychological dimension made up of difficulties in accepting insulin immediately, in fear of addiction and doubts about the therapy. On the basis of these results the sample was then divided into two subgroups, which were then tested and compared with the Adjective Check List. The subgroup that showed more fear, insecurity and initial resistance towards insulin therapy appeared to be more rigid and seemingly conforming. These people also revealed personality aspects compatible with the presence of passive-aggressive and avoidant traits.

Nutritional assessment in head injured patients through the study of rapid turnover visceral proteins.

BACKGROUND & AIMS: Nutritional monitoring of rapid turnover visceral protein is important in the recognition of malnutrition in patients admitted to the Intensive Care Unit (ICU). We studied prealbumin and retinol-binding protein in patients who received three different kinds of artificial nutrition in order to evaluate the appropriateness of artificial nutrition. METHODS: 45 consecutive head injury patients received enteral (Group A), parenteral (Group B) or both enteral and parenteral nutrition (Group C) at random. We considered these parameters: prealbumin, retinol binding protein and nitrogen balance before (T1), after 3 (T2), 7 (T3) and 11 (T4) days after the beginning of study. Statistical analysis was performed with Kruskal-Wallis test and Bonferroni's t -test. RESULTS: Plasma prealbumin and Retinol binding protein (RBP) showed an increasing of basal values during the study period in all groups (<< 0.0001) and more significantly in group A (Enteral nutrition P < 0. 001 vs Total parenteral nutrition (TPN) and Enteral P<< 0.01 vs Enteral and parenteral nutrition). CONCLUSION: Data obtained in the present study indicate that a laboratory is essential for monitoring nutritional assessment and for checking the appropriateness of nutritional therapy. We found prealbumin to be the most sensitive measure and found it to be the test of choice for early assessment and intervention.

Histidine 179 mutants of GTP cyclohydrolase I catalyze the formation of 2-amino-5-formylamino-6-ribofuranosylamino-4(3H)-pyrimidinone triphosphate.

GTP cyclohydrolase I catalyzes the conversion of GTP to dihydroneopterin triphosphate. The replacement of histidine 179 by other amino acids affords mutant enzymes that do not catalyze the formation of dihydroneopterin triphosphate. However, some of these mutant proteins catalyze the conversion of GTP to 2-amino-5-formylamino-6-ribofuranosylamino-4(3H)-pyrimidinone 5'-triphosphate as shown by multinuclear NMR analysis. The equilibrium constant for the reversible conversion of GTP to the ring-opened derivative is approximately 0.1. The wild-type enzyme converts the formylamino pyrimidine derivative to dihydroneopterin triphosphate; the rate is similar to that observed with GTP as substrate. The data support the conclusion that the formylamino pyrimidine derivative is an intermediate in the overall reaction catalyzed by GTP cyclohydrolase I.

[The psychological evaluation of patients with severe heart failure awaiting a heart transplant]. / Valutazione psicologica in pazienti con insufficienza cardiaca grave in attesa di trapianto cardiaco.

Because of the limitations resulting from the severity of heart failure, patients in the waiting list for cardiac transplantation often show a worsening in their social life. They usually present with psychological problems caused by symptoms, medical or surgical therapies and consequences on their own work. We have devised and utilized an experimental psychodiagnostic protocol to study the psychological characteristics of a sample of patients with heart failure (NYHA functional class III and IV) candidate to heart transplantation. Our study was particularly aimed at investigating the quality of life and the psychological mechanisms of adaptation. Findings show a strong attempt of denying the discomfort deriving from the disease and the expectation for transplant. Patients seem to have an adequate reaction to the illness and, otherwise, they feel anxiety and trouble that make very fragile their psychological adaptation. This behaviour is probably correlated with symptoms and the clinical history of heart failure, and does not match with a visible state of well-being that can be detected with a superficial analysis. Nevertheless patients have a good availability in receiving a psychological support from the whole medical staff (physicians, nurses): this suggests that the benefits deriving from a contemporary medical and psychological therapy are able to prevent the appearance of clear psychiatric symptoms. Additional studies involving larger samples of selected populations are needed to confirm the results of the present investigation.

[The influence of psychological factors on the patient's management of diabetes. Critical survey of psychodynamic models on personal management of diabetes]. / Influenza dei fattori psichici sull'autogestione del diabete. Rassegna critica dei contributi dei modelli psicodinamici sull'autogestione del diabete.

The authors have examined the currently accepted methods to face a chronic disease like diabetes. The person affected by this illness should learn to accept his/her limits and find a new identity. The aim of technical and scientific medicine is to teach the patient how to cope with the disease. However, in spite of the progress of the scientific research in this field, diabetes remains a poorly treated disease. A review of the literature shows that there is a deep interaction between diabetes and psychological states. Psychological disorders like depression and anxiety might be associated with the origin of diabetes and can affect its course. It seems that emotional factors have a more important role than education in diabetes care. The psychological aspect becomes even more important during adolescence, as the chronic illness can affect the normal development of the teen-ager who will deny it to protect himself. If the patient does not collaborate, his behaviour may be unconsciously aggressive and destructive. Some patients can use diabetes as a tool to act out aggressive feelings against themselves or the environment. Diabetes bad management becomes then the expression of their destructive narcissism which prevents them from finding a new identity. The collaboration of medical and psychological operators should help these patients to find a new identity which includes diabetes as an integrating part of their personality and enables them to cope with it under the guidance of the diabetes team.

Blood contamination of amniotic fluid after amniocentesis in relation to placental location.

The aim of the present study was to evaluate blood contamination of the amniotic fluid collected in 20 patients undergoing a second amniocentesis performed 2 weeks after a first procedure that had failed due to Pseudomonas aeruginosa contamination of the cell cultures. Red blood cell and haemoglobin concentrations in the amniotic fluid were significantly higher in patients who had undergone a transplacental procedure compared with patients in whom the placenta was not traversed with the needle. For both groups, blood contamination of the amniotic fluid was significantly higher compared with a control group of 20 patients undergoing amniocentesis for the first time. Significant blood contamination of the amniotic fluid after amniocentesis occurs in every instance if evaluated at a "second-look' procedure; the blood contamination is higher when an anterior placenta is traversed with the needle. The clinical significance of these findings needs to be further evaluated.

Transplacental amniocentesis: is it really a higher-risk procedure?

The aim of this study was to compare transplacental with non-transplacental amniocentesis in terms of related complications. Between January 1991 and December 1992, 4564 genetic amniocenteses were performed in 4527 patients (4491 singleton, 35 twin, and one triplet pregnancy) at 15-16 weeks of gestation. All the procedures were ultrasound-guided and performed by the same operator. In 1487 cases, an anterior placenta was traversed with the needle, whereas in 3077 cases, the needle was inserted directly into the amniotic cavity without traversing the placenta. After the exclusion of patients in whom amniotic cell culture failed or in whom an abnormal karyotype was obtained, and of patients lost to follow-up, a total of 4454 patients (98 per cent) were followed for 30 days after amniocentesis. Two spontaneous abortions occurred after a transplacental procedure, and five after a nontransplacental procedure (P = not significant). There were no episodes of amniotic fluid leakage in the first group, whereas 16 ruptures of the membranes that resolved spontaneously occurred in the second group (P < 0.01). Our data suggest that transplacental amniocentesis carries a similar abortive risk to and a lower risk of transient rupture of the membranes than non-transplacental amniocentesis and may therefore be preferred at the gestational period examined (15-16 weeks). However, the risk of feto-maternal haemorrhage, which is reported to be higher for a transplacental procedure, must be considered in the case of an anterior placenta.

[Recurrent organic abdominal pain. Psychosocial investigation]. / Dolori addominali ricorrenti su base organica. Indagine psicosociale.

This study has produced the following results. All the children with RAP show an excessive excitability and timidness, a strong insecurity and apprehension towards the society. The majority of the children show a strong dependence upon their relatives, they are not able to place themselves, as active subjects, in the present trality and to make plans for their future life (absence of interests and/or programmes about their autorealization). These children have a psychological maturity not corresponding to the physical one, even if there is no real strongly marked mental insufficiency. About 50% of the subjects have difficult relations with their siblings, friends and teachers, unlike the group examined (infact these difficulties are not seen).