Many qualitative and quantitative Magnetic Resonance Imaging (MRI) techniques have been applied to evaluate muscle fat degeneration in Duchenne muscular dystrophy (DMD) subjects, but only few studies ...have focused on the upper limbs. We reviewed the literature in order to evaluate the association between muscle MRI findings and motor function levels in the upper limbs of DMD patients. Ten studies with upper limb muscle MRI data were available. Four explored all upper limb segments, while six explored only the forearm. Functional assessments were performed in nine of the ten studies. All of the studies showed a significant correlation between muscle MRI changes and motor function levels in both ambulant and non-ambulant DMD patients.
The aim of the study was to evaluate the spectrum of upper limb functional activities and imaging finding in a cohort of patients affected by Duchenne muscular dystrophy. Thirty-one patients of age ...between 5 and 29 years were included in the study (17 ambulant and 14 non-ambulant). They were all assessed using the Performance of Upper Limb (PUL) test and muscle MRI of shoulder, arm and forearm in order to establish if the functional scores obtained at shoulder, mid and distal level related to specific patterns of involvement in each upper limb segment on muscle MRI. At shoulder level, latissimus dorsi, serratus anterior, infraspinatus and subscapularis were always involved, even in patients with full functional scores at shoulder level. Diffuse and severe involvement of all muscles was found in the patients with a PUL shoulder functional score of ≤ 5. At arm level biceps brachii, brachialis and triceps were generally concordantly involved or spared. Some degree of involvement could already be detected in patients with reduced scores on the PUL mid domain. They were generally severely involved in patients with functional scores less than 6 at mid-level. At distal level supinator and pronator muscles were often involved, followed by brachioradialis and, less frequently, by the muscles of the flexor compartment. The extensor muscles were generally completely spared. A diffuse and severe involvement was found only in patients who had very low scores (8 or below) on the PUL distal domain. The integrated use of functional scales and imaging allowed to establish patterns of involvement at each level, and the functional scores that were more frequently associated with diffuse and severe involvement.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background
Laminotomy has been introduced in surgical practice to reduce complications of laminectomy after surgery of tumors in the spinal canal. However, the posterior ligament complex, which is ...routinely interrupted to remove the laminoplasty segment and gain access to the spinal canal, has a tendency not to heal and can lead to progressive kyphosis and collapse.
Case presentation
A 5-month-old boy affected by a thoracolumbar extradural tumor extending along seven spinal levels was operated on. The tumor was exposed and completely resected by a one-piece laminotomy with preservation of the integrity of the posterior tension band at both extremities. After 1-year radiological examination ruled out spinal deformity.
Conclusion
The technique herein presented, which we named in situ laminotomy, allows to fully preserve the posterior tension band without reducing the exposure of the spinal canal in multilevel tumors. Additionally, the technique makes also the reconstruction of the spine elements very easy and rapid. However, longer follow-up is necessary to prove the effectiveness of this procedure in preventing long-term deformity and instability.
Organic–inorganic hybrid foams based on an alkali alumino-silicate matrix were prepared using different foaming methods. Firstly, silico-aluminate inorganic matrix, activated through a sodium ...silicate solution, was prepared at room temperature. The obtained viscous paste was expanded by means of silicon metal redox reaction in alkaline media in combination with protein-assisted foaming. The foamed systems were hardened at defined temperature and time and then characterized by FTIR, scanning electron microscopy, and compression tests. The high temperature behavior and specific surface area were also evaluated. The experimental findings highlighted that the combination of silicon metal and vegetable protein allowed tailoring hybrid foams with enhanced properties: good yield strength and thermal resistance typical of geopolymeric foam with a ductile behavior (toughness) and low density typical of organic foams.
We present the polarization-dependent highly absorptive in Ka-band composition of conventional polyurethane foam filled with in situ synthesized aerogel coated by reduced graphene oxide (rGO). The ...rGO-based aerogel was in situ prepared into the open-cell polyurethane foam (PUF) skeleton through a bidirectional freeze-drying process. The aerogel is composed of the flat lamellas stacks, possessing the anisotropic structure and unique electromagnetic properties. Further improvement of the electromagnetic shielding ability was possible by the rGO coating introduction as a coupling layer between PUF and rGO-based aerogel. This enhances the overall conductivity of the resulting composites: 1.41 + 3.33
S/m vs. 0.9 + 2.45
S/m for PUF loaded with in situ synthesized aerogel without rGO coating.With this mechanically robust plane easy to process coating one could achieve -20 dB by power with the record light structure (0.0462 g/cm²). That could compete in view of the weight per cm² even with graphene-based absorbers comprising either dielectric matching elements or back metal reflectors, or both.
Anisotropic aerogel-foam composites were developed by embedding a reduced graphene oxide (rGO)/chitosan aerogel directly into an open-cell polyurethane foam through an in situ bidirectional ...freeze-drying process. The resulting aerogel-foam composites possess both excellent compression-resilience performance and stable piezo-resistive properties due, respectively, to the excellent mechanical properties of polyurethane foams and to the presence of a chitosan-based aerogel loaded with rGO. The latter, indeed, provides outstanding electrical properties due to its conductive and parallel flat lamellar structure. It has been proven that both mechanical and piezo-resistive properties are stable even after 1000 loading/unloading cycles and a reduction of the electrical resistance of about 86% is observed upon the application of a 60% strain. The high sensitivity, long cycling life, and reliable performance over a wide strain range make this unique anisotropic aerogel-foam composite a highly promising candidate for the production of wearable sensors and healthcare monitoring devices.
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•Amberlyst-15 promotes DPE synthesis.•DPE density and viscosity were measured.•Intraparticle kinetic model was developed to describe all the experimental data.•Surface reaction ...kinetic laws were individuated to best fit the data.•The influence of internal diffusion was demonstrated to be influent.
In the present work, a catalytic screening using the most common heterogeneous acid catalysts was conducted, using as a raw material ethyl levulinate. Extensive catalyst screening revealed that Amberlyst-15 can be considered a very suitable catalyst to promote the DPE synthesis from ethyl levulinate and phenol. The use of ethyl levulinate allowed to obtain 100% selectivity towards p,p-DPE isomer, a precursor for the NIPU synthesis. A kinetic investigation was conducted to determine the influence of different parameters on the reaction rate. Finally, a mathematical model with intraparticle diffusion limitations was employed to describe the experimental data and to retrieve the kinetic as well as adsorption parameters via non-linear regression analysis.
Biotinidase deficiency (BTD) is an autosomal recessive inborn error of metabolism provoking progressive biotin depletion, which causes, in turn, multiple carboxylase deficiency. Its infantile onset ...is characterized by intractable seizures associated with lethargy, psychomotor regression, hypotonia, feeding and respiratory problems, and cutaneous abnormalities.
We describe a 52-month-old female whose clinical and neuroradiological pictures were consistent with myelopathy, which is generally more frequent in older patients, as well as with symptoms of an infantile onset of biotinidase deficiency, revealed at 17 months.
A biochemical biotinidase test revealed a profound deficiency of biotinidase detecting a 10% residual enzymatic activity, which led to the diagnosis of BTD. Gene sequencing revealed a compound heterozigous mutation (c.454A > C/c.1612C > T).
Our findings suggest that even if myelopathy is uncommonly reported in BTD, and generally occurs in older children, its presence in childhood-onset floppiness should always be considered as a possible marker for an atypical presentation of BTD. Although, until recently, BTD myelopathy was believed to be prevalent in older children, a spinal cord involvement has also been described in at least nine cases in early infancy. Thus, another early diagnosis suggests that myelopathy may be more frequent than previously thought, and it is probably underdiagnosed because spinal MRI is not always routinely performed on these children. Early recognition of BTD disease is important as it would lead to prompt treatment, preventing irreversible brain damage and increasing the chances of complete recovery.
Pozzolanic material-based geopolymer has been proposed as a solving methodology to the geohazards, due to pozzolanic collapsible soils widely present in the South Italy. The geopolymer was ...synthesized from pozzolana material under activation of NaOH 10 M or slurry of NaAlO₂ in NaOH 10 M solution. The specimens were cured at 25 °C and 100% RH for different ageing times. The effect of the two activation methods on the properties of the geopolymer was investigated by means of X-ray diffraction, scanning electron microscopy (SEM), FTIR spectroscopy, nuclear magnetic resonance (²⁷Al and ²⁹Si NMR) and uniaxial compression tests. XRD, NMR and IR analysis indicate the geopolymer is generated by the dissolution of the silico-aluminate phases present in the pozzolana and the successive re-organization in amorphous and crystalline neo-formed phases. The spectroscopic evidences confirm that the 4-coordinated Al atoms present in the neat pozzolana and in the NaAlO₂ change their coordination state splitting between 6- and 4-coordinated atoms, modifying the traditional chemistry of polysialate formation. SEM results show the synthesized geo-polymer maintained the granular morphology of the pozzolana and the geo-polymeric reactions occurred mainly at the surface of pozzolana particulates. Furthermore, uniaxial strength data increase gradually upon the curing time, until 40 MPa for the specimens activated with the slurry system.
The latest tendency of the scientific community regards the development of different classes of green materials able to solve pollution problems caused by industrial and human activity. In this ...paper, chitosan and diatomite were used to produce a broad-spectrum hybrid adsorbent, either in powder or in monolithic form for environmental pollutant removal. Diatomite-chitosan-based powders and porous diatomite-chitosan hybrids were prepared and characterized by chemical-physical, thermal and morphological analysis. Moreover, their adsorbent capacity towards anionic dye (Indigo Carmine) was also evaluated. Obtained data showed that chitosan improves the adsorption capacity of both systems, increasing the uptake of dye in both diatomite-chitosan systems.
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