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Mutations in nuclear-encoded protein subunits of the mitochondrial ribosome are an increasingly recognised cause of oxidative phosphorylation system (OXPHOS) disorders. Among them, mutations in the MRPL44 gene, encoding a structural protein of the large subunit of the mitochondrial ribosome, have been identified in four patients with OXPHOS defects and early-onset hypertrophic cardiomyopathy with or without additional clinical features. A 23-year-old individual with cardiac and skeletal myopathy, neurological involvement, and combined deficiency of OXPHOS complexes in skeletal muscle was clinically and genetically investigated. Analysis of whole-exome sequencing data revealed a homozygous mutation in MRPL44 (c.467 T?>?G), which was not present in the biological father, and a region of homozygosity involving most of chromosome 2, raising the possibility of uniparental disomy. Short-tandem repeat and genome-wide SNP microarray analyses of the family trio confirmed complete maternal uniparental isodisomy of chromosome 2. Mitochondrial ribosome assembly and mitochondrial translation were assessed in patient derived-fibroblasts. These studies confirmed that c.467 T?>?G affects the stability or assembly of the large subunit of the mitochondrial ribosome, leading to impaired mitochondrial protein synthesis and decreased levels of multiple OXPHOS components. This study provides evidence of complete maternal uniparental isodisomy of chromosome 2 in a patient with MRPL44-related disease, and confirms that MRLP44 mutations cause a mitochondrial translation defect that may present as a multisystem disorder with neurological involvement.

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Abstract

Benthic marine flora of Tuscan Archipelago has been studied. Several samples were collected along five islands and some rocks. This paper is a compendium of new and already published data, in which 267 species, varieties, forms and stadia of algae and seagrasses are listed: 5 Bangiophyceae, 182 Florideophyceae, 45 Phaeophyceae, 6 Chlorophyceae, 28 Bryopsidophyceae, 1 Angiospermae.  相似文献   
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Background

The opinions held by the general population on obstructive lung disease and inhaler devices could influence asthma and chronic obstructive pulmonary disorder (COPD) management and treatment adherence.The aim of the present public pragmatic survey was to evaluate the opinions, beliefs and perceptions of Italian people with respect to respiratory diseases as well as their perspectives on the use of inhaler devices.

Methods

This survey was conducted on a group of 2,008 individuals forming a representative sample of the Italian population aged 15 years and over. It was based on personal interviews that were administered in the homes of the respondents using a structured questionnaire that took approximately 30 minutes.

Results

Awareness of obstructive lung diseases is poor. Asthma, but not COPD, was perceived as a common and increasingly prevalent disease by the majority of the interviewees. Allergy, pollution and smoking were considered to be responsible for both of these diseases. The rates at which the respondents claimed to be suffering from asthma and COPD were lower than expected (4% and 2%, respectively). Inhaled drugs were recognised as the main treatment by 65% of the respondents. The great majority of respondents attributed positive characteristics to the inhaler device (e.g., safety, reliability, effectiveness, ease of use and practicality). Compared to people who have never used inhaler devices, individuals who suffer from asthma or COPD were more confident in their use and showed a greater belief in their safety, reliability and trustworthiness. People older than 64 years showed less attention to the properties of these devices.

Conclusions

The present results highlight the need for public interventions aimed at improving awareness of obstructive lung disease and reveal various potentialities and critical issues for inhaler device usage. Switching of devices was considered feasible by most of the interviewees, as long as the choice is carefully explained by their physician.  相似文献   
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Pathological and imaging data indicate that amyotrophic lateral sclerosis (ALS) is a multisystem disease involving several cerebral cortical areas. Advanced quantitative magnetic resonance imaging (MRI) techniques enable to explore in vivo the volume and microstructure of the cerebral cortex in ALS. We studied with a combined voxel-based morphometry (VBM) and magnetization transfer (MT) imaging approach the capability of MRI to identify the cortical areas affected by neurodegeneration in ALS patients. Eighteen ALS patients and 18 age-matched healthy controls were examined on a 1.5T scanner using a high-resolution 3D T1 weighted spoiled gradient recalled sequence with and without MT saturation pulse. A voxel-based analysis (VBA) was adopted in order to automatically compute the regional atrophy and MT ratio (MTr) changes of the entire cerebral cortex. By using a multimodal image analysis MTr was adjusted for local gray matter (GM) atrophy to investigate if MTr changes can be independent of atrophy of the cerebral cortex. VBA revealed several clusters of combined GM atrophy and MTr decrease in motor-related areas and extra-motor frontotemporal cortex. The multimodal image analysis identified areas of isolated MTr decrease in premotor and extra-motor frontotemporal areas. VBM and MTr are capable to detect the distribution of neurodegenerative alterations in the cortical GM of ALS patients, supporting the hypothesis of a multi-systemic involvement in ALS. MT imaging changes exist beyond volume loss in frontotemporal cortices.  相似文献   
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Exendin-4 is a molecule currently used, in its synthetic form exenatide, for the treatment of type 2 diabetes mellitus. Exendin-4 binds and activates the Glucagon-Like Peptide-1 Receptor (GLP-1R), thus inducing insulin release. More recently, additional biological properties have been associated to molecules that belong to the GLP-1 family. For instance, Peptide YY and Vasoactive Intestinal Peptide have been found to affect cell adhesion and migration and our previous data have shown a considerable actin cytoskeleton rearrangement after exendin-4 treatment. However, no data are currently available on the effects of exendin-4 on tumor cell motility. The aim of this study was to investigate the effects of this molecule on cell adhesion, differentiation and migration in two neuroblastoma cell lines, SH-SY5Y and SK-N-AS. We first demonstrated, by Extra Cellular Matrix cell adhesion arrays, that exendin-4 increased cell adhesion, in particular on a vitronectin substrate. Subsequently, we found that this molecule induced a more differentiated phenotype, as assessed by i) the evaluation of neurite-like protrusions in 3D cell cultures, ii) the analysis of the expression of neuronal markers and iii) electrophysiological studies. Furthermore, we demonstrated that exendin-4 reduced cell migration and counteracted anchorage-independent growth in neuroblastoma cells. Overall, these data indicate for the first time that exendin-4 may have anti-tumoral properties.  相似文献   
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Alignment of skeletal myoblasts is considered a critical step during myotube formation. The C2C12 cell line is frequently used as a model of skeletal muscle differentiation that can be induced by lowering the serum concentration in standard culture flasks. In order to mimic the striated architectures of skeletal muscles in vitro, micro‐patterning techniques and surface engineering have been proven as useful approaches for promoting elongation and alignment of C2C12 myoblasts, thereby enhancing the outgrowth of multi‐nucleated myotubes upon switching from growth media (GM) to differentiative media (DM). Herein, a layer‐by‐layer (LbL) polyelectrolyte multilayer deposition was combined with a micro‐molding in capillaries (MIMIC) method to simultaneously provide biochemical and geometrical instructive cues that induced the formation of tightly apposed and parallel arrays of differentiating myotubes from C2C12 cells maintained in GM media for 15 days. This study focuses on two different types of patterned/self‐assembled nanofilms based on alternated layers of poly (allylamine hydrochloride) (PAH)/poly(sodium 4‐styrene‐sulfonate) (PSS) as biocompatible but not biodegradable polymeric structures, or poly‐L ‐arginine sulfate salt (pARG)/dextran sulfate sodium salt (DXS) as both biocompatible and biodegradable surfaces. The influence of these microstructures as well as of the nanofilm composition on C2C12 skeletal muscle cells' differentiation and viability was evaluated and quantified, pointing to give a reference for skeletal muscle regenerative potential in culture conditions that do not promote it. At this regard, our results validate PEM microstructured devices, to a greater extent for (PAH/PSS)5‐coated microgrooves, as biocompatible and innovative tools for tissue engineering applications and molecular dissection of events controlling C2C12 skeletal muscle regeneration without switching to their optimal differentiative culture media in vitro. Biotechnol. Bioeng. 2013; 110: 586–596. © 2012 Wiley Periodicals, Inc.  相似文献   
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