Multi-center observational study on occurrence and related clinical factors of neurogenic heterotopic ossification in patients with disorders of consciousness.

Aims: to assess occurrence and clinical correlates of neurogenic heterotopic ossifications (NHO) in patients with prolonged disorder of consciousness (DoC).Design: multi-center cross-sectional observational study.Setting: 23 intensive neurorehabilitation units.Subjects: 287 patients with prolonged disorder of consciousness (DoC; 150 in vegetative state, VS, and 128 in minimally conscious state, MCS) of different etiology (vascular = 125, traumatic = 83, anoxic = 56, others = 14).Main Measures: clinical evidence of NHO confirmed by standard radiological and/or sonographic evaluation; Coma Recovery Scale-Revised; Disability Rating Scale (DRS); Early Rehabilitation Barthel Index; presence of ventilator support, spasticity, bone fractures and paroxysmal sympathetic hyperactivity.Results: 31 patients (11.2%) presented NHO. Univariate analyses showed that NHO was associated with VS diagnosis, traumatic etiology, high DRS category and total score, and high occurrence of limb spasticity and bone fractures. A cluster-corrected binary logistic regression model (excluding spasticity available in a subset of patients) showed that only lower DRS total score and presence of bone fractures were independently associated with NHO.Conclusions: NHO are relatively frequent in patients with DoC, and are independently associated with functional disability, bone fractures and spasticity. These findings contribute to identifying patients with DoC prone to develop NHO and requiring special interventions to improve functional recovery.

Multi-center study on overall clinical complexity of patients with prolonged disorders of consciousness of different etiologies.

Aim: to assess overall clinical complexity of patients with acquired disorders of consciousness (DoC) in vegetative state/unresponsive wakefulness syndrome (VS/UWS) vs. minimally conscious state- MCS) and in different etiologies..Design: Multi-center cross-sectional observational study.Setting: 23 intensive neurorehabilitation units.Subjects: 264 patients with DoC in the post-acute phase: VS/UWS = 141, and MCS = 123 due to vascular (n = 125), traumatic (n = 83) or anoxic (n = 56) brain injury.Main Measures: Coma Recovery Scale-Revised, and Disability Rating Scale (DRS); presence of medical devices (e.g., for eating or breathing); occurrence and severity of medical complications.Results: patients in DoC, and particularly those in VS/UWS, showed severe overall clinical complexity. Anoxic patients had higher overall clinical complexity, lower level of responsiveness/consciousness, higher functional disability, and higher needs of medical devices. Vascular patients had worse premorbid clinical comorbidities. The two etiologies showed a comparable rate of MC, higher than that observed in traumatic etiology.Conclusion: overall clinical complexity is significantly higher in VS/UWS than in MCS, and in non-traumatic vs. traumatic etiology. These findings could explain the worse clinical evolution reported in anoxic and vascular etiologies and in VS/UWS patients and contribute to plan patient-tailored care and rehabilitation programmes.

Analysis of Italian regulations on pathways of care for patients in a vegetative or minimally conscious state.

Different rehabilitation models for persons diagnosed with disorders of consciousness have been proposed in Europe during the last decade. In Italy, the Ministry of Health has defined a national healthcare model, although, to date, there is a lack of information on how this has been implemented at regional level. The INCARICO project collected information on different regional regulations, analysing ethical aspects and mapping care facilities (numbers of beds and medical units) in eleven regional territories. The researchers found a total of 106 laws; differences emerged both between regions and versus the national model, showing that patients with the same diagnosis may follow different pathways of care. An ongoing cultural shift from a treatment-oriented medical approach towards a care-oriented integrated biopsychosocial approach was found in all the welfare and healthcare systems analysed. Future studies are needed to explore the relationship between healthcare systems and the quality of services provided.

Acoustic excitations in glassy sorbitol and their relation with the fragility and the boson peak.

We report a detailed analysis of the dynamic structure factor of glassy sorbitol by using inelastic X-ray scattering and previously measured light scattering data [B. Ruta, G. Monaco, F. Scarponi, and D. Fioretto, Philos. Mag. 88, 3939 (2008)]. The thus obtained knowledge on the density-density fluctuations at both the mesoscopic and macroscopic length scale has been used to address two debated topics concerning the vibrational properties of glasses. The relation between the acoustic modes and the universal boson peak (BP) appearing in the vibrational density of states of glasses has been investigated, also in relation with some recent theoretical models. Moreover, the connection between the elastic properties of glasses and the slowing down of the structural relaxation process in supercooled liquids has been scrutinized. For what concerns the first issue, it is here shown that the wave vector dependence of the acoustic excitations can be used, in sorbitol, to quantitatively reproduce the shape of the boson peak, supporting the relation between BP and acoustic modes. For what concerns the second issue, a proper study of elasticity over a wide spatial range is shown to be fundamental in order to investigate the relation between elastic properties and the slowing down of the dynamics in the corresponding supercooled liquid phase.

Nonergodicity factor, fragility, and elastic properties of polymeric glassy sulfur.

We present a detailed investigation of the vibrational dynamics of glassy sulfur (g-S). The large frequency range spanned in this study has allowed us to carefully scrutinize the elastic properties of g-S and to analyze their relation to various features of both the glassy and the liquid state. In particular, the acoustic properties of g-S present a quasi-harmonic behavior in the THz frequency range, while at lower frequency, in the GHz range, they are affected by a strong anharmonic contribution. Moreover, the high frequency (THz) dynamics of g-S does not present signatures of the elastic anomalies recently observed in a number of glasses. Despite this apparent contradiction, we show that this finding is not in disagreement with the previous ones. Finally, by considering the correct long wavelength limit of the density fluctuations in the glassy state, we estimate the continuum limit of the nonergodicity factor and we investigate recently proposed relations between the fast dynamics of glasses and the slow dynamics of the corresponding viscous melts.

Acoustic dissipation and density of states in liquid, supercooled, and glassy glycerol.

Combined Brillouin spectra collected at visible, ultraviolet, and x-ray frequencies are used to reconstruct the imaginary part of the acoustic compliance J'' over a wide frequency range between 0.5 GHz and 5 THz. For liquid, supercooled, and glassy glycerol, J'' is found to be linearly dependent on the tagged-particle susceptibility measured by incoherent neutron scattering up to ≃1 THz, giving evidence of a clear relation between acoustic power dissipation and density of states. A simple but general formalism is presented to quantitatively explain this relation, thus clarifying the connection between the quasielastic component observed in neutron scattering experiments and the fast relaxation dynamics probed by Brillouin scattering.

Hydrophobic hydration of tert-butyl alcohol studied by Brillouin light and inelastic ultraviolet scattering.

The longitudinal viscosity of diluted water-tert-butyl alcohol solutions in the 10 GHz frequency region has been measured by means of Brillouin light scattering and inelastic ultraviolet scattering. The main advantage of our hypersonic investigation compared to more traditional ultrasonic measurements is that in the gigahertz frequency range slow relaxation processes involving the alcohol dynamics are completely unrelaxed, so that the measured viscosity mainly originates from the hydrogen bond restructuring of water. In contrast with previous determinations, we estimate an activation energy which is independent from the alcohol mole fraction up to X = 0.1, and comparable to that of bulk water. A simple two-component model is used to describe the steep increase of viscosity with increasing alcohol mole fraction, and a retardation factor 1.7 ± 0.2 is found between the relaxation times of hydration and bulk water. These findings endorse a dynamic scenario where the slowing down of hydration water is mainly due to a reduction of configurational entropy and does not involve an arrested, icelike, dynamics.

Communication: High-frequency acoustic excitations and boson peak in glasses: A study of their temperature dependence.

The results of a combined experimental study of the high-frequency acoustic dynamics and of the vibrational density of states (VDOS) as a function of temperature in a glass of sorbitol are reported here. The excess in the VDOS at approximately 4.5 meV over the Debye, elastic continuum prediction (boson peak) is found to be clearly related to anomalies observed in the acoustic dispersion curve in the mesoscopic wavenumber range of few nm(-1). The quasiharmonic temperature dependence of the acoustic dispersion curves offers a natural explanation for the observed scaling of the boson peak with the elastic medium properties.

Light scattering spectra of water in trehalose aqueous solutions: evidence for two different solvent relaxation processes.

Light scattering spectra on aqueous solutions of trehalose were recorded in a wide frequency range combining the use of a double monochromator and a multipass Fabry-Perot interferometer. Experimental results indicate the presence of a slow relaxation mode related to the solute dynamics, which is clearly separated from the solvent one. The spectral analysis reveals the existence of two separate solvent relaxation processes assigned to hydrating and bulk water molecules. The picosecond dynamics of water molecules directly interacting with the solute (proximal water) is consistently delayed with the corresponding relaxation time increase is about 5-6 times compared to the bulk. The slowing down induced by the sugar on the water dynamics mainly involves a restricted hydration layer constituted of 16-18 water molecules. These results improve our knowledge about the influence of carbohydrates on the fast rearrangement dynamics of water and may serve as a model to gain important insight on basic solvation properties of other biorelevant systems in aqueous media.

Onset of the alpha-relaxation in the glass-forming solution LiCl-6H2O revealed by Brillouin scattering techniques.

We measured the dynamic structure factor of the liquid and glassy phases of the LiCl-6H(2)O solution by means of inelastic scattering of radiation in the visible, UV, and x-ray range, between 1 GHz and 10 THz, and by means of photon-correlation spectroscopy, between 0.01 Hz and 20 kHz. The measurements were performed in the temperature range between 353 and 80 K. Our data show that a single-relaxation process exists at high temperature, which has features similar to those of the single relaxation of pure water. Upon cooling the system below approximately 220 K, this single mode starts to differentiate two processes, a structural (alpha-) and a secondary (beta-) relaxation. As the temperature is decreased, the beta-relaxation is the vanishing continuation of the single, high-temperature process, while the onset of the alpha-relaxation occurs at the expense of the beta-process.

Origin of the lambda transition in liquid sulfur.

Developing a novel experimental technique, we applied photon correlation spectroscopy using infrared radiation in liquid sulfur around T(lambda), i.e., in the temperature range where an abrupt increase in viscosity by 4 orders of magnitude is observed upon heating within few degrees. This allowed us - overcoming photoinduced and absorption effects at visible wavelengths - to reveal a chain relaxation process with characteristic time in the millisecond range. These results do rehabilitate the validity of the Maxwell relation in sulfur from an apparent failure, allowing rationalizing of the mechanical and thermodynamic behavior of this system within a viscoelastic scenario.

Rubberlike dynamics in sulphur above the lambda-transition temperature.

The high-frequency acoustic dynamics of sulfur across the liquid-liquid, lambda transition has been studied using inelastic x-ray scattering. The combination of these high-frequency data with lower frequency, literature data indicates that liquid sulfur develops, in the high-temperature, polymeric solution phase, some characteristic features of a rubber. In particular, entanglement coupling among polymeric chains plays a relevant role in the dynamics of this liquid phase.

[Review of 87 cases of scoliosis surgically treated]. / Revisione di 87 casi di scoliosi operata.

BACKGROUND: The authors compared the results and complications in surgical treatment of idiopathic scoliosis with Harrington's rod instrumentation with subtrasversal wires in dorsal treat. METHODS: A research on 87 cases operated on for idiopathic scoliosis from 1987 to 1995 is carried out. The 87 cases include 65 females and 25 males, 16 years old in average (range, 11 to 30). The curvature in Cobb's degrees and rotation of vertebrae with Raimondi's method on radiographs take just before, 15 days later and an year later on operation was measured. The patients have been divided into two groups: the first of 77 patients operated with Harrington's rod instrumentation; the second of 10 patients operated with Harrington's rod instrumentation and subtrasversal wires. RESULTS: In a general analysis without taking in to consideration the type and the seriousness of curvature it was obtained a better correction and derotation of vertebrae in patients of second group. The same group with wires had obtained a better correction and derotation of vertebrae in dorsal scoliosis from 40 degrees to 60 degrees and in the double scoliosis, while the first group obtained better results in dorsal scoliosis from 60 degrees to 80 degrees and in derotation of vertebrae on dorsal treat of double scoliosis. One case of pseudarthrosis in every group was observed. Any neurological complication were observed. CONCLUSIONS: The conclusions is drawn that the application of subtrasversal wire improves the Harrington's technique for the correction and derotation of dorsal and double scoliosis without neurological complications sometimes present with subliminar wires.