Regeneration of adult skeletal muscle is an asynchronous process requiring the activation, proliferation and fusion of satellite cells, to form new muscle fibres. This study was designed to determine ...the pattern of expression in vivo of the two myogenic regulatory factors, Myf5 and MyoD during this process. Cardiotoxin was used to induce regeneration in the gastrocnemius and soleus muscles of heterozygous Myf5-nlacZ mice, and the muscles were assayed for the presence of (beta)-galactosidase (Myf5) and MyoD. Adult satellite cells identified by M-cadherin labelling, when activated, initially express either MyoD or Myf5 or both myogenic factors. Subsequently all proliferating myoblasts express MyoD and part of the population is (beta)-galactosidase (Myf5) positive. Furthermore, we demonstrate that activated satellite cells, which express either Myf5 or MyoD, do not accumulate selectively on fast or slow muscle fibres.
The dissociation of HORMA domain protein 2 (HORMAD2) from the synaptonemal complex is tightly regulated. This study reveals that the N-terminal region of HORMAD2 is critical for its dissociation from ...synapsed meiotic chromosomes.
During meiosis, homologous chromosomes undergo synapsis and recombination. HORMA domain proteins regulate key processes in meiosis. Mammalian HORMAD1 and HORMAD2 localize to unsynapsed chromosome axes but are removed upon synapsis by the TRIP13 AAA+ ATPase. TRIP13 engages the N-terminal region of HORMA domain proteins to induce an open conformation, resulting in the disassembly of protein complexes. Here, we report introduction of a 3×FLAG-HA tag to the N-terminus of HORMAD2 in mice. Coimmunoprecipitation coupled with mass spectrometry identified HORMAD1 and SYCP2 as HORMAD2-associated proteins in the testis. Unexpectedly, the N-terminal tagging of HORMAD2 resulted in its abnormal persistence along synapsed regions in pachynema and ectopic localization to telomeres in diplonema. Super-resolution microscopy revealed that 3×FLAG-HA-HORMAD2 was distributed along the central region of the synaptonemal complex, whereas wild-type HORMAD1 persisted along the lateral elements in 3×FLAG-HA-HORMAD2 meiocytes. Although homozygous mice completed meiosis and were fertile, homozygous males exhibited a significant reduction in sperm count. Collectively, these results suggest that the N-terminus of HORMAD2 is important for its timely removal from meiotic chromosome axes.
We designed, realized, and tested a 2.5-Gb/s optical wireless communication (OWC) system prototype, that should be employed in high energy physics (HEP) experiments, such as the compact muon solenoid ...(CMS). The system consists of off-the-shelf components, mainly a vertical cavity surface emitting laser (VCSEL) and a PIN photodiode with a proper ball lens. Since it should be used to transmit data among particle sensors in neighboring rings of the CMS, its target distance is 10 cm. Its most attractive feature is that it does not require a (complex) active tracking system because its measured tolerance to misalignment is around <inline-formula><tex-math notation="LaTeX">\pm</tex-math> </inline-formula>1 mm (at <inline-formula><tex-math notation="LaTeX">10^{-12}</tex-math></inline-formula> bit error rate). We also report the X-rays irradiation tests of all components (Quartz lens, VCSEL, and PIN photodiode): None of them showed any degradation up till 238-Mrad (Si) dose. These results indicate that the designed OWC can be a viable solution for future HEP experiments.
Different cardiac stem/progenitor cells have been recently identified in the post-natal heart. We describe here the identification, clonal expansion and characterization of self-renewing progenitors ...that differ from those previously described for high spontaneous cardiac differentiation. Unique coexpression of endothelial and pericyte markers identify these cells as cardiac mesoangioblasts and allow prospective isolation and clonal expansion from the juvenile mouse ventricle. Cardiac mesoangioblasts express many cardiac transcription factors and spontaneously differentiate into beating cardiomyocytes that assemble mature sarcomeres and express typical cardiac ion channels. Cells similarly isolated from the atrium do not spontaneously differentiate. When injected into the ventricle after coronary artery ligation, cardiac mesoangioblasts efficiently generate new myocardium in the peripheral area of the necrotic zone, as they do when grafted in the embryonic chick heart. These data identify cardiac mesoangioblasts as committed progenitors, downstream of earlier stem/progenitor cells and suitable for the cell therapy of a subset of juvenile cardiac diseases.
The Italian Dystonia Registry is a multicenter data collection system that will prospectively assess the phenomenology and natural history of adult-onset dystonia and will serve as a basis for future ...etiological, pathophysiological and therapeutic studies. In the first 6 months of activity, 20 movement disorders Italian centres have adhered to the registry and 664 patients have been recruited. Baseline historical information from this cohort provides the first general overview of adult-onset dystonia in Italy. The cohort was characterized by a lower education level than the Italian population, and most patients were employed as artisans, builders, farmers, or unskilled workers. The clinical features of our sample confirmed the peculiar characteristics of adult-onset dystonia, i.e. gender preference, peak age at onset in the sixth decade, predominance of cervical dystonia and blepharospasm over the other focal dystonias, and a tendency to spread to adjacent body parts, The sample also confirmed the association between eye symptoms and blepharospasm, whereas no clear association emerged between extracranial injury and dystonia in a body site. Adult-onset dystonia patients and the Italian population shared similar burden of arterial hypertension, type 2 diabetes, coronary heart disease, dyslipidemia, and hypothyroidism, while hyperthyroidism was more frequent in the dystonia population. Geographic stratification of the study population yielded no major difference in the most clinical and phenomenological features of dystonia. Analysis of baseline information from recruited patients indicates that the Italian Dystonia Registry may be a useful tool to capture the real world clinical practice of physicians that visit dystonia patients.
Particle tracking for future experiments at colliders is an incredible challenge in terms of sensor technology and readout. Simulation tools are a crucial ingredient to investigate new layouts able ...to cope with harsh radiation conditions and, at the same time, provide valuable timing information for track finding algorithms. Detailed and numerous simulations of energy deposits as well as sensor and front-end electronics responses imply a heavy usage of computing resources. In this paper, we present two software packages that,
via
massive parallelization and dedicated algorithms, allow for a significant speed-up in simulation time.
Efficient delivery of stem cells to heart regions is still a major problem for cell therapy. Here, we report experiments aimed to improve migration of mouse and human cardiac mesoangioblasts to the ...damaged heart. Cardiac mesoangioblasts were induced to transmigrate through the endothelium by factors released by cardiomyocytes or cytokines, among which stromal-derived factor 1 (SDF-1) was the most potent. Cardiac mesoangioblasts were also delivered into the left ventricular (LV) chamber of mice after coronary artery ligation (CAL), and their in vivo homing to the damaged heart was found to be quite modest. Pretreatment of cardiac mesoangioblasts with SDF-1 or transient expression of L-selectin induced a two- to three-fold increase in their transmigration and homing to the damaged heart. Therefore, combined pretreatment with SDF-1 and L-selectin generated modified cardiac mesoangioblasts, 50% of which, after injection into the LV chamber of mice early after CAL, home directly to the damaged free wall of the heart. Finally, modified mouse cardiac mesoangioblasts, injected into the LV chamber regenerate a larger surface of the ventricle in long-term experiments in comparison with their control counterparts. This study defines the requirements for efficient homing of cardiac mesoangioblasts to the damaged heart and offers a new potent tool to optimize efficiency of future cell therapy protocols for cardiovascular diseases.
Abstract Spinal hemangioblastomas are benign and highly vascular tumors accounting for 1–5% of intramedullary spinal tumors in surgical series. Surgery is curative in sporadic cases. We present the ...description of a surgical technique to safely resect an intramedullary hemangioblastoma. A dorsal midline myelotomy provides an excellent exposure of the tumor and identification of the feeding arteries. Interruption of these arteries and precise dissection of the tumor from the cord tissue followed by division of the venous drainage allow the in toto excision of the tumor. Closure of the dorsal myelotomy may be achieved with sequential fusion of the pial and arachnoid edges using a “welding” technique.
We propose a realistic 3D positioning system for indoor navigation that exploits visible Light Emitting Diodes (LEDs), placed on the ceiling. A unique frequency tone is assigned to each lamp and ...modulates its intensity in periodic time slots. The Time Difference of Arrival (TDOA) is measured without the need of a synchronization system between the sources and the receiver, then it is used to accurately estimate the receiver position. We first describe the theoretical approach, then propose the model and characterize the possible sources of noise. Finally, we demonstrate the proof-of-concept of the proposed system by simulation of lightwave propagation. Namely, we assess its performance by using Montecarlo simulations in a common room and estimate the impact of the different implementation parameters on the accuracy of the proposed solution. We find that, in realistic conditions, the technique allows for centimeter precision. Pushing the device requirements, the precision can be further increased to a sub-centimeter accuracy.
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