80 research outputs found

    Siringomielia cervicale secondaria a singole masse intracraniche occupanti spazio nel cane: caratteristiche di risonanza magnetica e fattori di rischio

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    The aims of the present study are 1), to investigate cervical syringomyelia (SM) secondary to single space-occupying intracranial lesions in dogs, and 2), to evaluate potential risk factors based on brain and cervical magnetic resonance imaging (MRI) studies conducted for the diagnosis of these two conditions. As a multicentric retrospective single cohort study, we recruited a population of dogs affected by a single space-occupying brain lesion and we divided it into two groups, based on the presence or absence of cervical SM. These two groups were compared for signalment (age, sex, and cranial morphology) and for MRI findings (relative intracranial mass volume, relative perilesional oedema volume, mass effect, ventriculomegaly and cerebellar herniation). Based on the current knowledge about SM and its aetiopathogenesis, our initial hypothesis considered factors predisposing to cervical SM development being lesions with substantial relative mass volume, localisation in the caudal cranial fossa, cerebellar transforaminal herniation and/or obstructive hydrocephalus. Our statistical analysis revealed that intracranial mass with relative volumetric index higher than 0.028 and causing cerebellar transforaminal herniation and/or obstructive hydrocephalus predispose to cervical SM formation. Therefore, in presence of these findings on a brain MRI study is indicated to extend the diagnostic imaging protocol to the cervical spine to check for the potential presence of SM. Conversely, the detection of cervical SM, in the absence of any additional cervical disease, addresses the clinician to extend the MRI study to the brain for the search of a potential primary mass lesion

    A novel strategy to enhance interfacial adhesion in fiber-reinforced calcium phosphate cement

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    Calcium phosphate cements (CPCs) are extensively used as synthetic bone grafts, but their poor toughness limits their use to non-load-bearing applications. Reinforcement through introduction of fibers and yarns has been evaluated in various studies but always resulted in a decrease in elastic modulus or bending strength when compared to the CPC matrix. The aim of the present work was to improve the interfacial adhesion between fibers and matrix to obtain tougher biocompatible fiber-reinforced calcium phosphate cements (FRCPCs). This was done by adding a polymer solution to the matrix, with chemical affinity to the reinforcing chitosan fibers, namely trimethyl chitosan (TMC). The improved wettability and chemical affinity of the chitosan fibers with the TMC in the liquid phase led to an enhancement of the interfacial adhesion. This resulted in an increase of the work of fracture (several hundred-fold increase), while the elastic modulus and bending strength were maintained similar to the materials without additives. Additionally the TMC-modified CPCs showed suitable biocompatibility with an osteoblastic cell line.Preprin

    Biomimetic versus sintered macroporous calcium phosphate scaffolds enhanced bone regeneration and human mesenchymal stromal cell engraftment in calvarial defects

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    In contrast to sintered calcium phosphates (CaPs) commonly employed as scaffolds to deliver mesenchymal stromal cells (MSCs) targeting bone repair, low temperature setting conditions of calcium deficient hydroxyapatite (CDHA) yield biomimetic topology with high specific surface area. In this study, the healing capacity of CDHA administering MSCs to bone defects is evaluated for the first time and compared with sintered beta-tricalcium phosphate (ß-TCP) constructs sharing the same interconnected macroporosity. Xeno-free expanded human bone marrow MSCs attached to the surface of the hydrophobic ß-TCP constructs, while infiltrating the pores of the hydrophilic CDHA. Implantation of MSCs on CaPs for 8 weeks in calvaria defects of nude mice exhibited complete healing, with bone formation aligned along the periphery of ß-TCP, and conversely distributed within the pores of CDHA. Human monocyte-osteoclast differentiation was inhibited in vitro by direct culture on CDHA compared to ß-TCP biomaterials and indirectly by administration of MSC-conditioned media generated on CDHA, while MSCs increased osteoclastogenesis in both CaPs in vivo. MSC engraftment was significantly higher in CDHA constructs, and also correlated positively with bone in-growth in scaffolds. These findings demonstrate that biomimetic CDHA are favorable carriers for MSC therapies and should be explored further towards clinical bone regeneration strategies. Statement of significance Delivery of mesenchymal stromal cells (MSCs) on calcium phosphate (CaP) biomaterials enhances reconstruction of bone defects. Traditional CaPs are produced at high temperature, but calcium deficient hydroxyapatite (CDHA) prepared at room temperature yields a surface structure more similar to native bone mineral. The objective of this study was to compare the capacity of biomimetic CDHA scaffolds with sintered ß-TCP scaffolds for bone repair mediated by MSCs for the first time. In vitro, greater cell infiltration occurred in CDHA scaffolds and following 8 weeks in vivo, MSC engraftment was higher in CDHA compared to ß-TCP, as was bone in-growth. These findings demonstrate the impact of material features such as surface structure, and highlight that CDHA should be explored towards clinical bone regeneration strategies.Peer ReviewedPostprint (author's final draft

    Impacto del viaje de Freire a Valencia

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    In the publications of Freire's trip, errors are detected that makes invisible both its impact and those who made it possible. An analysis of the documentation, 6 interviews with people who made the trip possible, 6 with professionals and 2 with family members in Valencia who are transforming their schools and 2 dialogical observations have been carried out. The results make it clear: 1) Those who proposed this trip both to Freire and to the Regional Ministry are Flecha and Jesús Gomez 'Pato'. 2) The reason is the approval by the Valencian Parliament of the Law on Adult Education, whose 'Report and draft for its preliminary project' had been entrusted to Flecha, who was hired to elaborate it. 3) Some publications ignore both facts, distorting the meaning of this journey and Freire's work. 4) The impact has been more profound in their infant, primary and secondary education and more transient in their adult education. 5) The values shared by Valencian education means that more and more people are demanding that we overcome these distortions and give deserved recognition to those who allowed us to have Paulo here

    Design of calcium phosphate scaffolds with controlled simvastatin release by plasma polymerisation

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    Calcium Phosphates (CaPs) have excellent bone regeneration capacity, and their combination with specific drugs is of interest because it allows adding new functionalities. In CaPs, drug release is mainly driven by diffusion, which is strongly affected by the porosity of the matrix and the drug-material interaction. Therefore, it is very difficult to tune their drug release properties beyond their intrinsic properties. Furthermore, when the CaPs are designed as scaffolds, the increased complexity of the macrostructure further complicates the issue.; This work investigates for the first time the use of biocompatible plasma-polymers to provide a tool to control drug release from drug-loaded CaP scaffolds with complex surfaces and intricate 3D structure. Two different CaPs were selected displaying great differences in microstructure: low-temperature CaPs (Calcium-deficient hydroxyapatite cements, CDHA) and sintered CaP ceramics (beta-Tricalcium Phosphate, beta-TCP). The deposition of PCL-co-PEG (1: 4) copolymers on CaPs was achieved by a low pressure plasma process, which allowed coating the inner regions of the scaffolds up to a certain depth. The coating covered the micro and nanopores of the CaPs surface and produced complex geometries presenting a nano and micro rough morphology which lead to low wettability despite the hydrophilicity of the copolymer. Plasma coating with PCL-co-PEG on scaffolds loaded with Simvastatin acid (potentially osteogenic and angiogenic) allowed delaying and modulating the drug release from the bone scaffolds depending on the thickness of the layer deposited, which, in turn depends on the initial specific surface area of the CaP. (C) 2016 Elsevier Ltd. All rights reserved.Peer ReviewedPostprint (author's final draft

    Emerging risk factors and the dose-response relationship between physical activity and lone atrial fibrillation: a prospective case-control study

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    A history of a parts per thousand yen2000 h of vigorous endurance training, tall stature, abdominal obesity, and OSA are frequently encountered as risk factors in patients with Ln-AF. Fewer than 2000 total hours of high-intensity endurance training associates with reduced Ln-AF risk

    Attitudes of the autism community to early autism research

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    Investigation into the earliest signs of autism in infants has become a significant sub-field of autism research. This work invokes specific ethical concerns such as: use of ‘at-risk’ language; communicating study findings to parents; and the future perspective of enrolled infants when they reach adulthood. The current study aimed to ground this research field in an understanding of the perspectives of members of the autism community. Following focus groups to identify topics, an online survey was distributed to autistic adults, parents of children with autism, and practitioners in health and education settings across eleven European countries. Survey respondents (n=2317) were positively disposed towards early autism research and there was significant overlap in their priorities for the field, and preferred language to describe infant research participants. However there were also differences including overall less favourable endorsement of early autism research by autistic adults relative to other groups and a dislike of the phrase ‘at-risk’ to describe infant participants, in all groups except healthcare practitioners. The findings overall indicate that the autism community in Europe is supportive of early autism research. Researchers should endeavour to maintain this by continuing to take community perspectives into account

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
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