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Mechanical performance of auxetic polyurethane foam for antivibration glove applications
In this study the static and dynamic characteristics of conventional open cell
polyurethane (PU), of auxetic (negative Poissonâs ratio) and of iso-density foams
were analysed. The specimens were produced from conventional gray open-cells
polyurethane foam with 30-35 pores/inch and 0.0027 g/cm3 density, by means of
process which has been previously defined by the authors. Poissonâs ratio
measurements were performed under quasi-static conditions using an MTS 858 servohydraulic
test machine and a video image acquisition system. For the auxetic foams
the results suggested similar behaviour to that previously reported in the literature,
with significant increases in stiffness during compressive loading, and a significant
dependence of the Poissonâs ratio on the applied strain. Transmissibility tests,
performed in accordance with the ISO 13753 procedure for antivibration glove
materials, suggested a strong dependence of the transmissibility on the foam
manufacturing parameters. Within the frequency range from 10 to 31.5 Hz the
transmissibility was found to be greater than 1, while it was less than 1 at all
frequencies greater than 31.5 Hz. The transmissibility results were similar to the mean
values for 80 resilient materials tested by Koton et. al., but were higher than the five
best materials (not all polymeric) identified by the same researchers. In this study it
has been suggested that the resilient behaviour of glove isolation materials should also
be evaluated in terms of the indentation characteristics. A simple, linear elastic, Finite
Element simulation was therefore performed, and the indentation results suggested
that auxetic foams offer a significant decrease in compressive stresses with respect to
conventional PU foams
Frizzled receptor 6 marks rare, highly tumourigenic stem-like cells in mouse and human neuroblastomas
Copyright © 2011 Cantilena et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 3.0 License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The article was made available through the Brunel Open Access Publishing Fund.Wnt signalling is an important component of vertebrate development, required for specification of the neural crest. Ten Wnt receptors [Frizzled receptor 1-10 (Fzd1-10)] have been identified so far, some of which are expressed in the developing nervous system and the neural crest. Here we show that expression of one such receptors, Fzd6, predicts poor survival in neuroblastoma patients and marks rare, HIF1/2 α-positive cells in tumour hypoxic areas. Fzd6 positive neuroblastoma cells form neurospheres with high efficiency, are resistant to doxorubicin killing and express high levels of mesenchymal markers such as Twist1 and Notch1. Expression of Fzd6 is required for the expression of genes of the noncanonical Wnt pathway and the spheres forming activity. When transplanted into immunodeficient mice, neuroblastoma cells expressing the Fzd6 marker grow more aggressively than their Fzd6 negative counterparts. We conclude that Fzd6 is a new surface marker of aggressive neuroblastoma cells with stem cell-like features.This work was sponsored by the Wellcome Trust, the RICC cancer fund, SPARKS, the Italian Association for Cancer Research, Regione Liguria and the Italian Ministry of Health
IgG4 related disease in elderly: A case report
IgG4-related systemic disease (IgG4-RSD) is an emerging autoimmune disorder that may affect several organs, with signs of organ fibrosis, storiform masses for hystopathological plasmacellular infiltration and plasmatic elevation of IgG4. This clinical condition frequently occurs in the sixth decade and may be considered an autoimmunity of the elderly; the disease may have a smouldering course with frequent misdiagnosis for the co-occurrence of comorbidity and clinical complexity. The present case report describes the clinical case of an 81 years old woman admitted to the geriatric ward for remittent fever and functional decline. The past clinical history reported an isolated CT scan suggestive of retroperitoneal fibrosis of unknown origin with and a drug regimen that included chronic corticosteroids (prednisone 5 mg oad). The in hospital diagnostic workout demonstrated the presence of a thoracic aneurysm. Several possible diagnoses among inflammatory, autoimmune (connective tissue disease, vasculitis, sarcoidosis, amyloidosis), infectious (mycotic) or neoplastic conditions were ruled out, as well as any drug association with higher risk of retroperitoneal fibrosis. Thus, the clinical hypothesis of an IgG4 chronic periaortitis was formulated due to the co-occurrence of all the three major components: the presence of a retroperitoneal fibrosis, IgG4 related abdominal aortitis and peryaneurysmal fibrosis. Patient\u2019s comorbidity did not allow performing the histological analysis. The present clinical case is original and adds knowledge to the 76 cases of thoracic aortitis due to IgG4 systemic disease out of the 3482 cases of disease reported so far. Further clinical investigation is needed to provide a homogeneous diagnostic workout for tailored early therapeutic intervention on the single geriatric patient. Moreover, a growing awareness of the disease is needed, especially in geriatrics, to providing a better standard of care and to improving the disease clinical knowledge and managemen
Therapeutic filmmaking, strategic psychotherapy and autism spectrum disorder: An integrated approach.
Ions and water transmembrane transport in nervous and testicular cultured cells in low gravity conditions
Aim of the present study was to investigate on the possible alter- ations induced by on ground modeled microgravity on ion-water transport proteins at cellular level. For the purpose we used astrocytes, C6 line, neurons (NT2 line from human teratocarci-
noma) and testicular cells (germ cells, Sertoli cells, and Leydig cells; primary cultures from trypsinised prepuberal pig testes). Modeled microgravity was achieved by a desktop 3D Random Positioning Machine, cultures were kept rotating for 30â, 1h and 24h. After 30â, immunopositivity for the antibodies to Na+/K+ATPase and Na+/K+/Cl- co-transporters was greatly diminished, the plasma membrane appeared to be altered, and the mitochondria inner cristae were disrupted. Immunostaining to the antibody to the water channel aquaporin 4 was very bright. After 1h at random rotation immunostaining for the heat shock protein Hsp27 was visible, After 24h, immunostaining for the ion transport proteins was again like that of the controls,plasma membrane and the mitochondria were again normal. Immunostaining for aquaporin 4 become again similar to that of the controls. We conclude that low gravity induces only tran- sient alterations in the cellâs transmembrane ion-water trans- port: the cells are able to adapt to the gravity vector changes in few hours
Perampanel and Visuospatial Skills in Children With Epilepsy
Introduction: Perampanel (PER) is a non-competitive AMPA glutamate receptor antagonist approved for focal and generalized seizures as add-on therapy. PER does not seem to negatively affect the cognitive profile in children and adolescents, but its influence on visuospatial abilities is still to be assessed. The aim of our study was to assess visuospatial skills through a standardized neuropsychological evaluation in adolescents taking PER for 12 months. Methods: Our sample included 46 adolescents aged 12â18 years with focal and generalized drug-resistant epilepsy already in therapy with one or two antiseizure medications. Changes in visuospatial perception and memory were assessed by the ReyâOsterrieth Complex Figure Test at baseline (before taking PER) and after 12 months of pharmacological treatment. Executive functions and non-verbal intelligence were also assessed at baseline. Results: After 12 months of PER therapy, the mean scores on the ReyâOsterrieth Complex Figure Test remained almost unchanged for both visuospatial perception and visuospatial memory skills. At baseline, visuospatial memory was related to executive function, and visuospatial perception was related to executive function and non-verbal intelligence. Conclusions: Adjunctive treatment with PER did not negatively affect visuospatial skills. No adverse event effects have been reported after 12 months of follow-up, and this suggests a good tolerability in the middle-to-long term
Ecotoxicity of basil (Ocimum Basilicum) extract in aquaculture feeds: Is it really eco-safe for the aquatic environment?
Plant extract and essential oils are gaining application in aquaculture, but data about their environmental impact are limited and their potential effects on aquatic organisms are largely unknown. For this study, ecotoxicity tests were performed under standardized conditions on fish feed supplemented with 3 % w/w of a basil supercritical extract (F1-BEO; substance A), F1-BEO extract (substance B), and fish feed without F1-BEO extract (substance C) on three model species of different trophic levels (bacteria, primary producer, primary consumer) considered representative for freshwater (Aliivibrio fischeri, Raphidocelis subcapitata, Daphnia magna) and marine (A. fischeri, Phaeodactylum tricornutum, Paracentrotus lividus) ecosystems. Ecotoxicological response was largely comparable within the same trophic level (whichever the ecosystem). EC50 was not calculable in the concentration range here tested (3.9â500 mg/L) for freshwater and marine microalgae, suggesting that none of the substances were toxic for primary producers. Reduction of A. fischeri bioluminescence at the tested concentration (0.5â10 mg/L) was observed only for substance A (EC50 9.53 mg/L and 9 mg/L for freshwater and marine ecosystems, respectively). Notably, in P. lividus embryotoxicity was higher for substances A (EC50 1.80 mg/L) and C (EC50 4.6 mg/L) than for substance B (EC50 7.10 mg/L), suggesting a toxic effect due to feed dissolution. In contrast, substance B was more toxic (EC50 0.34 mg/L) in D. magna than substances A (EC50 3.98 mg/L) and C (EC50 5.50 mg/L). Based on the Globally Harmonized System of Classification and Labelling of Chemicals, all substances were categorized Acute 2, except for substance A which was categorized Acute 1 for D. magna. Overall, the substances were found to be potentially toxic for an aquatic ecosystem, especially for primary consumer. Further study of plant extract and essential oils is needed to better understand their effects and fate on the aquatic environment
Neuropsychological profile, emotional/behavioral problems, and parental stress in children with neurodevelopmental disorders
Background: The aim of our study was to trace a specific neuropsychological profile, to investigate emotional-behavioral problems and parental stress in children with Autism Spectrum Disorder Level 1/High functioning (ASD-HF), Specific Learning Disorders (SLD) and Attention Deficit/Hyperactivity Disorder (ADHD) disorders and to highlight similarities and differences among the three groups. Methods: We retrospectively collected the data from a total of 62 subjects with ASD-HF (n = 19) ADHD (n = 21), SLD (n = 22) and 20 typical development. All the participants underwent neuropsychological standardized test for the evaluation of cognitive profile (Wechsler Intelligence Scale for Children Fourth Edition-WISC-IV), behavioral and emotional problems (Child Behavior CheckList CBCL), and parental stress (Parental Stress Index Short Form-PSI-SF). The scores of the ASD-HF, ADHD, and SLD groups were compared using non-parametric statistic methods (Kruskall-Wallis H test and U Mann-Whitney for post-hoc analysis). Results: The ASD-HF group were significantly higher in all areas of the WISC-IV than the other two clinical groups. The SLD group performed significantly lower than ASD-HF in Working Memory Index. The SLD group showed lower scores on the somatic problems subscale than the other two groups. In the Difficult Child subscale of the PSI-SF, parents of ADHD children scored lower than the mothers of SLD subjects and higher than the fathers of SLD subjects. In all three groups there are specific deficiencies compared to the control group in the cognitive profile, behavioral and emotional problems, and parental stress. Conclusions: Our comparative analysis highlighted similarities and differences in three groups of children with different neurodevelopmental disorders, helping to better define cognitive, behavioral, and emotional characteristics of these children and parental stress of their parents
Facial emotion recognition in children and adolescents with specific learning disorder
(1) Background: Some recent studies suggest that children and adolescents with different neurodevelopmental disorders perform worse in emotions recognition through facial expressions (ER) compared with typically developing peers. This impairment is also described in children with Specific Learning Disorders (SLD), compromising their scholastic achievement, social functioning, and quality of life. The purpose of our study is to evaluate ER skills in children and adolescents with SLD compared to a control group without learning disorders, and correlate them with intelligence and executive functions. (2) Materials and Methods: Our work is a cross-sectional observational study. Sixty-three children and adolescents aged between 8 and 16 years, diagnosed with SLD, and 32 sex/age-matched controls without learning disorders were recruited. All participants were administered standardized neuropsychological tests, evaluating facial emotion recognition (NEPSY-II), executive functions (EpiTrack Junior), and intelligence profile (WISC-IV). (3) Results: Emotion recognition mean score was significantly lower in the SLD group than in the controls group on the MannâWhitney U test for unpaired samples (p < 0.001). The SLD group performed significantly lower than the control group in their abilities to identify neutral expressions, happiness, sadness, anger, and fear compared to controls (p < 0.001). ER scores were positively correlated to the executive functions scores. There was no correlation with the Total Intelligence Quotient scores but there is a significant positive correlation with Working Memory Index and Processing Speed Index measured by WISC.IV. (4) Conclusions: Our study showed that children and adolescents with Specific Learning Disorders have facial emotion recognition impairment when compared with a group of peers without learning disorders. ER abilities were independent of their global intelligence but potentially related to executive functions
Mussel watch program for microplastics in the Mediterranean sea: Identification of biomarkers of exposure using Mytilus galloprovincialis
Microplastics (MPs) are ubiquitous pollutants that have also been detected in the aquatic ecosystems at high concentrations. The use of shellfish as bioindicators is widespread for assessing and monitoring the environmental quality in both freshwater and marine environments. On this path, biomarkers represent an effective tool in monitoring programs. This minireview would broaden the existing knowledge on biomarkers of MPs in the Mediterranean mussel Mytilus galloprovincialis. This species was selected as it is widely distributed across the Mediterranean Sea and used as a bioindicator to monitor the presence of MPs in the marine environment. The literature search returned only 11 studies, mainly related to oxidative stress biomarkers. Although certain biomarkers were explored to estimate the effects of MPs on M. galloprovincialis, a battery of standardized and validated biomarkers as well as the inclusion of new ones are needed in future studies to obtain more comparable and robust findings across the Mediterranean Sea
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