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Modern and contemporary art materials are generally prone to irreversible colour changes upon exposure to light and oxidizing agents. Graphene can be produced in thin large sheets, blocks ultraviolet light, and is impermeable to oxygen, moisture and corrosive agents; therefore, it has the potential to be used as a transparent layer for the protection of art objects in museums, during storage and transportation. Here we show that a single-layer or multilayer graphene veil, produced by chemical vapour deposition, can be deposited over artworks to protect them efficiently against colour fading, with a protection factor of up to 70%. We also show that this process is reversible since the graphene protective layer can be removed using a soft rubber eraser without causing any damage to the artwork. We have also explored a complementary contactless graphene-based route for colour protection that is based on the deposition of graphene on picture framing glass for use when the direct application of graphene is not feasible due to surface roughness or artwork fragility. Overall, the present results are a proof of concept of the potential use of graphene as an effective and removable protective advanced material to prevent colour fading in artworks.
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Cellulose-based artefacts are highly prone to degradation, especially in the presence of acidic compounds, which trigger the depolymerization of cellulose chains and lead to a loss in the original mechanical resistance of the material. Calcium hydroxide nanoparticles dispersed in organic solvent have been recently proposed for the deacidification of cellulose-based artworks. In this work, changes induced on paper by a deacidification treatment, following an acidification bath, were studied by nuclear magnetic resonance (NMR) relaxometry and by the so-called NMR diffraction of water trapped in the cellulose network. The deacidification treatment modifies intrachain and interchain bonds in hydrolyzed and degraded cellulose, leading to a buffered cellulose network configuration, which is similar to that characterizing the untreated reference sample in terms of relaxation parameters. Overall, calcium hydroxide nanoparticles are demonstrated effective in hindering the degradation of cellulose induced by acids and ageing in strong environmental conditions, even from the standpoint of cellulose network arrangement. It is worth noting, too, that the unilateral NMR device used for the relaxation measurements may represent a powerful tool for the preservation of cellulose-based artworks because it allows for the monitoring of the conservation status of cellulose in a completely non-invasive manner.
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HYPOTHESIS: Strongly degraded cellulosic artworks usually need deacidification and consolidation. Alkaline nanoparticles are known to be effective in neutralizing the acidity, while cellulose nanocrystals have the potential to be used as compatible and effective strengthening agents. EXPERIMENTS: We have grafted cellulose nanocrystals with oleic acid using a 1'1-carbonyldiimidazole-mediated procedure, to increase their dispersibility in organic solvents, and synthesized Ca(OH)2 or CaCO3 nanoparticles via a solvothermal process. Grafted nanocellulose and alkaline nanoparticles were used to prepare ethanol-based "hybrids". Prior to the application, the physico-chemical properties of nanocellulose dispersions and "hybrids" were studied by rheology and small-angle X-ray scattering. FINDINGS: Cellulose nanocrystals were effectively grafted and stably dispersed in ethanol. It was shown that the use of ethanol as a dispersing medium, and the addition of alkaline nanoparticles act in a synergistic way, increasing the interactions between grafted cellulose nanocrystals, leading to the formation of clusters. These dispersions are thixotropic, a behavior particularly appealing to conservation purposes, since they can be applied in the liquid state, or, when a more confined application is required, they can be applied in a gel-like state. As a result of the application, an improvement in the mechanical properties of paper and an increase of pH were obtained.
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It is increasingly accepted that survival alone is an inadequate measure of the success of childhood brain tumour treatments. Consequently, there is growing emphasis on capturing quality of survival. Ependymomas are the third most frequently occurring brain tumours in childhood and present significant clinical challenges. European Society of Paediatric Oncology Ependymoma II is a comprehensive international program aiming to evaluate outcomes under different treatment regimens and improve diagnostic accuracy. Importantly, there has been agreement to lower the age at which children with posterior fossa ependymoma undergo focal irradiation from three years to either eighteen months or one year of age. Hitherto radiotherapy in Europe had been reserved for children over three years due to concerns over adverse cognitive outcomes following irradiation of the developing brain. There is therefore a duty of care to include longitudinal cognitive follow-up and this has been agreed as an essential trial outcome. Discussions between representatives of 18 participating European countries over 10 years have yielded European consensus for an internationally accepted test battery for follow-up of childhood ependymoma survivors. The 'Core-Plus' model incorporates a two-tier approach to assessment by specifying core tests to establish a minimum dataset where resources are limited, whilst maintaining scope for comprehensive assessment where feasible. The challenges leading to the development of the Core-Plus model are presented alongside learning from the initial stages of the trial. We propose that this model could provide a solution for future international trials addressing both childhood brain tumours and other conditions associated with cognitive morbidity.
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Cuidados Posteriores/métodos , Neoplasias Encefálicas/radioterapia , Ensayos Clínicos como Asunto/métodos , Cognición/efectos de la radiación , Ependimoma/radioterapia , Adolescente , Supervivientes de Cáncer/psicología , Niño , Preescolar , Irradiación Craneana/efectos adversos , Europa (Continente) , Femenino , Humanos , Lactante , Masculino , MorbilidadRESUMEN
HYPOTHESIS: The reaction of Ca(OH)2 with CO2 to form CaCO3 (carbonation process) is of high interest for construction materials, environmental applications and art preservation. Here, the "Boundary Nucleation and Growth" model (BNGM) was adopted for the first time to consider the effect of the surface area of Ca(OH)2 nanoparticles on the carbonation kinetics. EXPERIMENTS: The carbonation of commercial and laboratory-prepared particles' dispersions was monitored by Fourier Transform Infrared Spectroscopy, and the BNGM was used to analyze the data. The contributions of nucleation and growth of CaCO3 were evaluated separately. FINDINGS: During carbonation the boundary regions of the Ca(OH)2 particles are densely populated with CaCO3 nuclei, and transform early with subsequent thickening of slab-like regions centered on the original boundaries. A BNGM limiting case equation was thus used to fit the kinetics, where the transformation rate decreases exponentially with time. The carbonation rate constants, activation energies, and linear growth rate were calculated. Particles with larger size and lower surface area show a decrease of the rate at which the non-nucleated grains between the boundaries transform, and an increase of the ending time of Ca(OH)2 transformation. The effect of temperature on the carbonation kinetics and on the CaCO3 polymorphs formation was evaluated.
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Abstract The attention to nuclear clustering has been renewed due to the study of weakly bound nuclei at the drip lines. In particular, clustering structural properties in medium-mass systems have been studied by looking at the competition between the evaporation and pre-equilibrium particle emission in central collisions. Although for light nuclei at an excitation energy close to the particle separation value there are experimental evidence of such structure effects, this is still not the case for heavier systems since the determination of pre-formed clusters within nuclear matter is less obvious. Two systems, leading to the same 81Rb* compound nucleus, have been studied at the same beam velocity 16 AMeV: 16O + 65Cu and 19F + 62Ni. The experiment has been performed using the GARFIELD + RCo detection system installed at the Legnaro National Laboratories.Light charged particles energy distributions and multiplicities have been compared with different statistical and dynamical model calculations. From the first comparison between the two systems a difference in the fast α-decay channel has been evidenced, which can be related to the difference in the projectile structure. Recent data analysis results and comparisons with model calculations are presented in this contribution.
Resumen La atención a la agrupación nuclear se ha renovado debido al estudio de núcleos débilmente unidos en las líneas de goteo. En particular, se han estudiado las propiedades estructurales del agrupamiento en sistemas de masa media al observar la competencia entre la evaporación y la emisión de partículas de preequilibrio en colisiones centrales. Aunque para núcleos ligeros a una energía de excitación cercana al valor de separación de la partícula hay evidencia experimental de tales efectos de estructura, este no es el caso para sistemas más pesados ya que la determinación de agrupamientos preformados dentro de la materia nuclear es menos obvia. Se han estudiado dos sistemas, que conducen al mismo núcleo compuesto 81Rb *, a la misma velocidad de haz 16 AMeV: 16O + 65Cu y 19F + 62Ni. El experimento se ha realizado utilizando el sistema de detección GARFIELD + RCo instalado en los Laboratorios Nacionales Legnaro. Las distribuciones de energía y las multiplicidades de partículas de carga ligera se han comparado con diferentes cálculos de modelos estadísticos y dinámicos. Desde la primera comparación entre los dos sistemas, se ha evidenciado una diferencia en el canal de desintegración α rápida, que se puede relacionar con la diferencia en la estructura del proyectil. En esta contribución se presentan los resultados del análisis de datos recientes y las comparaciones con los cálculos del modelo.
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PURPOSE: An intensive therapeutic strategy for metastatic medulloblastoma was launched in 1998 in our Institution. The aim of this study was to examine the long-term quality of life (QoL) in survivor patients at least 3 years after the end of the treatment. METHODS: Patients were asked to complete self-administered QoL questionnaires. An index of physical impairment (IPI) was scored (range 0-100; the lower the score the better) based on clinical objective observations. Patients were divided into two groups (lower IPI group, and higher IPI group) and descriptively compared accordingly. RESULTS: The study was completed by 25/33 eligible patients. Despite patients with a higher IPI reported worse perceived health condition, they had better emotional and psychological scores than those with a lower IPI in all QoL questionnaires. CONCLUSION: In our sample, patients with more severe objective and perceived physical impairments reported a better psychosocial QoL, possibly because the greater attention paid to them by society and family contributes to a better adjustment in long-term survivors. On this base, it should be recommended that all survivors receive a strong support as the most impaired patients.
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Neoplasias Cerebelosas/radioterapia , Meduloblastoma/radioterapia , Radioterapia/efectos adversos , Sobrevivientes/psicología , Adolescente , Niño , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Masculino , Calidad de Vida , Radioterapia/métodos , Encuestas y CuestionariosRESUMEN
AIM: Sleep is essential for children's physical and mental recovery and it is indispensable for their growth, for endocrine and for immune function, and for the development of cognitive behavioral skills. The purpose of this study is to describe the impact of hospitalization on the sleep patterns of newborns, infants and toddlers, as well as mothers' perceptions of any changes in their children's sleep patterns. METHODS: This was a single-centre cross-sectional study. The study included children aged up to 2 years who had been hospitalized for more than two days, selected by accidental sampling. Data were collected using an anonymous questionnaire with open and closed questions administered to mothers. RESULTS: Two hundred and one children aged on average 11.2 months (SD 10.3) were enrolled in the study. The percentage of children who at home used to sleep less than 5 hours a night increased by 4.7% in hospital, while the percentage of children sleeping 9 to 11 hours at home decreased by 5.9% in hospital. In hospital mothers put their children to bed later than at home. Indeed, the number of individuals going to bed between 9 and 10 p.m. decreased by 9.8% in hospital, while the number of children going to bed between 10 and 11 p.m. increased by 10.1%. The number of children who had 2 to 4 awakenings per night increased by 13.9% and the number of those who had 4 to 6 nocturnal awakenings increased by 4.8%; 50.5% of mothers reported that their children's sleep was interrupted by nurses to provide care. Mothers generally perceived their children's sleep as adequate, even if they noticed that their children were more restless and irritable. Mothers with only one child reported that they had more difficulty helping their children fall asleep (P=0.02). CONCLUSION: The study highlights the need to review the routine in paediatric wards on the basis of the sleep needs of children. Further studies are needed to estimate the effectiveness of the specific measures suggested by mothers.
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Hospitalización , Trastornos del Sueño-Vigilia/epidemiología , Sueño/fisiología , Estudios Transversales , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Encuestas y CuestionariosRESUMEN
AIM: Non nutritive suckling has been always used by mothers for calming and comforting infants and young children. Previous studies have suggested that pacifiers may get contaminated but only three studies have shown a possible association between the use of pacifiers and diarrhea or enteric infections. The goal of this study was to investigate whether the early start of pacifier within the first month of life is a risk factor for diarrhea in early childhood. METHODS: Case-control study. Subjects 12 to 36 month old were recruited. Cases were children with at least 1 episode of diarrhea per year of life. RESULTS: Among cases (N.=63), those who had started using pacifier in the first month of life were 61.9%, while among controls (N.=78) they were 29.4%, OR 3.89, CI95% 1.92-7.85. Type and frequency of pacifier hygiene practices were not associated with diarrhea. CONCLUSION: Our results suggest that the recommendation to postpone pacifier use after the first month of life not to interfere with the duration of breastfeeding, may have also the effect to reduce the risk of episodes of diarrhea in the first three years of life.
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Diarrea/epidemiología , Diarrea/etiología , Cuidado del Lactante , Chupetes/efectos adversos , Chupetes/estadística & datos numéricos , Adulto , Estudios de Casos y Controles , Preescolar , Femenino , Humanos , Higiene , Lactante , Cuidado del Lactante/métodos , Italia/epidemiología , Masculino , Madres , Factores de Riesgo , Encuestas y Cuestionarios , Factores de TiempoRESUMEN
Solitary median maxillary central incisor syndrome (SMMCI) syndrome is a unique developmental abnormality arising from an unknown event occurring between the 35th and 38th days in utero, and involving mieline structure of the head including the cranial bones, the maxilla and its container dentition (specifically the central incisor tooth germ), together with other midline structures of the body. The SMMCI tooth may be possibly occur as an isolated trait or in association with many other midline developmental anomalies. It is estimated to occur in 1:50000 live births. There is a wide variability in the phenotypic spectrum. SMMCI is considered one of the most minimal expressions of the holoprosencephaly spectrum. Mutation in the Sonic Hedgehog homolog (SHH) gene may be associated with SSMMCI, but recent studies suggests the existence of several other candidate genes. We described two patients with SMMCI. They presented a solitary median maxillary incisor, short stature, hipotelorism and corpus callosus anomalies found on magnetic resonance imaging (MRI). They also present severe hiponatremia. At the best of our knowledge, this is the first report of cases of SMMCI with hiponatremia. We suggest that the sodium disorder may be secondary to syndrome of inappropriate secretion of antidiuretic hormone (SIADH).
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Holoprosencefalia , Incisivo/anomalías , Maxilar/anomalías , Humanos , Lactante , Masculino , SíndromeRESUMEN
Gestational diabetes insipidus (GDI) refers to the state of excessive water intake and hypotonic polyuria. Those cases manifesting in pregnancy and referred to as GDI may persist thereafter or may be a transient latent form that resolves after delivery. Microscopic examination of affected subjects has not been previously reported. In the literature, there are various case reports and case series on diabetes insipidus in pregnancy. In this study, we present a case that had transient diabetes insipidus during pregnancy in which the placenta was examined.
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Diabetes Insípida/patología , Placenta/patología , Complicaciones del Embarazo/patología , Adulto , Diabetes Insípida/fisiopatología , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/fisiopatologíaRESUMEN
SEN is a newly discovered blood-transmissible virus. Among its variants, SENV-D and -H are most often associated with non-A, -E hepatitis. Very little is known about the risk of vertical transmission of the virus. By using polymerase chain reaction with specific primers for SENV-D and -H, we investigated the prevalence of SENV-H and -D infection, the transmission rate of SENV infection and clinical features of SENV-infected children in 89 hepatitis C virus (HCV)-positive human immunodeficiency virus type 1-negative mothers. SENV infection was found in 36 (40%) mothers, and SENV-D was more frequent than SENV-H infection (34/36, 94%vs 5/36, 14%, P < 0.01). No difference in SENV infection rates was found between injection drug user (IDU) mothers (17/51, 33%) and mothers with no risk for bloodborne infection (19/38, 50%, P = ns). SENV-H infection was found only in IDU mothers and mothers with HCV genotype1b. Both SENV-D and -H can be transmitted to the offspring with an overall rate of 47%. Vertical transmission of HCV does not facilitate SENV infection of the offspring. Among 17 SENV-infected children, none was co-infected with HCV. Maternal HCV genotype or viral load does not interfere with mother-to-infant transmission of SENV. Persistence of SENV infection was demonstrated in 100% of infected children after 1-year follow-up, but none had clinical evidence of liver disease.
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Infecciones por Virus ADN/complicaciones , Infecciones por Virus ADN/transmisión , Hepatitis C/complicaciones , Transmisión Vertical de Enfermedad Infecciosa , Torque teno virus , Niño , Infecciones por Virus ADN/clasificación , Infecciones por Virus ADN/epidemiología , Infecciones por Virus ADN/virología , Femenino , Estudios de Seguimiento , Genotipo , Hepacivirus/genética , Hepatitis C/sangre , Hepatitis C/clasificación , Hepatitis C/genética , Hepatitis C/virología , Humanos , Lactante , Madres , Reacción en Cadena de la Polimerasa , Embarazo , Prevalencia , ARN Viral/sangre , Factores de Tiempo , Carga ViralRESUMEN
Mother-child human leukocyte antigen (HLA)diversity is protective for vertical transmission of some viruses. The aim of this study is to evaluate the role of mother-child HLA diversity on hepatitis C virus (HCV) vertical transmission. Forty consecutive HCV infected and 46 consecutive control uninfected children born to HCV-RNA positive mothers were evaluated for HLA class-1 type concordance with their mothers. No significant difference in the degree of HLA concordance was found between HCV infected and uninfected children both when A, B, C (p=0.30) and when only A and B alleles were evaluated (p=0.59). Mother-infant HLA concordance does not affect HCV vertical transmission.
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Antígenos HLA/genética , Hepacivirus , Hepatitis C Crónica/transmisión , Transmisión Vertical de Enfermedad Infecciosa , Adulto , Alelos , Variación Antigénica/genética , Femenino , Hepatitis C Crónica/congénito , Hepatitis C Crónica/virología , Prueba de Histocompatibilidad , Humanos , Recién Nacido , Embarazo , ARN/biosíntesis , ARN/genéticaRESUMEN
BACKGROUND AND OBJECTIVE: In the perivascular sheath of the brachial plexus, the volume of anaesthetic solution determines the quality of anaesthetic cover. Fibrous septa may divide the perivascular space into compartments, leading to inadequate diffusion of the anaesthetic solution. The aim of our study was to obtain good anaesthesia and less complications using high volume of low concentration anaesthetic solution, overcoming the obstacle of the septa with a double approach to the scalene sheath. METHODS: Sixty patients scheduled for shoulder capsuloplasty received both Winnie interscalene brachial plexus block and Pippa proximal cranial needle approach. The patients were randomly assigned to two groups. A constant dose of local anaesthetic was administered to each group: Group I (30 patients) received high volume (60 mL of anaesthetic solution) and Group II (30 patients) received low volume of solution (30 mL of anaesthetic solution). Sensory and motor block in the upper limb and complications were evaluated. RESULTS: In all the patients the quality of anaesthesia obtained at the surgical site was excellent. In Group I also the areas supplied by the medial cutaneous nerves of the arm and forearm, ulnar, median and radial nerves were blocked (P < 0.002). Complications were only observed in Group II and consisted of bradycardia and hypotension (66% of the patients) and phrenic nerve paresis (27% of the patients). CONCLUSIONS: The lower concentration of the anaesthetic solution avoids complications while increased volume provides good analgesic cover. The combination of the Winnie interscalene plexus block and the Pippa proximal cranial needle approach should contribute to fill up the scalene sheath overcoming the septa obstacles.
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Anestésicos Locales/administración & dosificación , Anestésicos Locales/efectos adversos , Plexo Braquial/efectos de los fármacos , Bloqueo Nervioso/efectos adversos , Agonistas Adrenérgicos/administración & dosificación , Adulto , Anciano , Plexo Braquial/irrigación sanguínea , Bradicardia/inducido químicamente , Bupivacaína/administración & dosificación , Bupivacaína/efectos adversos , Epinefrina/administración & dosificación , Femenino , Humanos , Hipotensión/inducido químicamente , Lidocaína/administración & dosificación , Masculino , Persona de Mediana Edad , Bloqueo Nervioso/métodos , Paresia/inducido químicamente , Nervio Frénico/efectos de los fármacos , Articulación del Hombro/inervación , Articulación del Hombro/cirugíaRESUMEN
Genetic and biochemical prenatal diagnosis was performed at 11 weeks of gestation in a family with a proband affected by mut methylmalonic aciduria (MMA) and homozygotes for the MUT gene c.643G>A (p.Gly215Ser) mutation. Both chorionic villus and amniotic fluid samples were used. The presence of high levels of methylmalonic acid and propionylcarnitine determined by gas chromatography/mass spectrometry and LC/MS/MS analysis, respectively, and the identification of the p.Gly215Ser at a homozygous level in foetal DNA allowed a certain, rapid and early diagnosis. To our knowledge, this is the first mut MMA prenatal diagnosis carried out by genetic and biochemical approach.
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Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Ácido Metilmalónico/orina , Diagnóstico Prenatal/métodos , Errores Innatos del Metabolismo de los Aminoácidos/genética , Secuencia de Bases , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Edad Gestacional , Humanos , Datos de Secuencia Molecular , EmbarazoRESUMEN
Multiple symmetrical lipomatosis, also known as Madelung disease, Launois-Bensaude syndrome, and benign symmetrical lipomatosis, is an uncommon disease that is characterized by the presence of multiple and symmetrical deposits of nonencapsulated adipose tissue in the neck, upper trunk, arms, and legs. It affects mainly men, with a higher incidence in the Mediterranean area, and is typically associated with high alcohol consumption and a high prevalence of peripheral neuropathy that usually appears long after the development of lipomatous masses. We report the case of a patient with involvement of the scrotum. We present clinical, ultrasound, and magnetic resonance appearances of these scrotal lipomatous masses for the first time.
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Enfermedades de los Genitales Masculinos/diagnóstico , Lipomatosis Simétrica Múltiple/diagnóstico , Escroto/patología , Adulto , Humanos , Imagen por Resonancia Magnética , Masculino , Escroto/diagnóstico por imagen , UltrasonografíaRESUMEN
Intrahepatic cysts are generally classified as congenital, traumatic, infectious or neoplastic. Non-parasitic hepatic cysts (NPHCs) include simple cysts and adult polycystic liver disease in which the liver is diffusely occupied by cysts. NPHCs usually reach a large size before causing symptoms, unless a complication such as rupture, bleeding, infection, obstructive jaundice or neoplastic transformation occurs. We report the case of a 67-year-old man with spontaneous rupture of simple liver cyst. The clinical pictures and the unusual ultrasound features of this rare condition are discussed.
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Quistes/diagnóstico por imagen , Hepatopatías/diagnóstico por imagen , Anciano , Humanos , Masculino , Remisión Espontánea , Rotura Espontánea/diagnóstico por imagen , UltrasonografíaRESUMEN
OBJECTIVE: To define and differentiate psychological and adjustment problems due to brain injury or brain tumour in children and adolescents. METHODS: Two groups of patients with acquired brain lesions (24 post-traumatic patients and 22 brain tumour survivors), ranging in age between 8-15 years, received a psychological evaluation, including the Child Behaviour Checklist for Ages 4-18 (CBCL) and the Vineland Behaviour Adaptive Scales (VABS). RESULTS: Both groups showed psychological and social adjustment problems. Post-traumatic patients were more impaired than brain tumour survivors. Social adjustment problems were associated to externalizing problems in post-traumatic patients and internalizing problems in brain tumour surviving patients. CONCLUSIONS: These differences in psychological and behavioural disorders between the two groups must necessarily be considered when developing psychological treatment, rehabilitation plan and social re-entry.