28 research outputs found
SILICONE MIGRATION FROM RUPTURE BREAST IMPLANT. WHAT SHOULD BE DONE? REPORT OF THREE CASES AND REVIEW OF LITERATURE
Silicone implants are widely used in aesthetic and reconstructive breast surgery. Rupture of a breast implants is a well-known complication. Silicone leakage from a rupture or silicone bleeding can accumulate in lymphnodes because the silicone migrates through the lymphatics, and it can reach local or distant nodes. The systemic effects of silicone are unknow and object of debate. We report three cases of silicone migration from breast implants rupture in oncological patients. We aim to describe the correct diagnosis and treatment according to the date of the literatur
Dynamics of Mechanical Signal Transmission through Prestressed Stress Fibers
Transmission of mechanical stimuli through the actin cytoskeleton has been proposed as a mechanism for rapid long-distance mechanotransduction in cells; however, a quantitative understanding of the dynamics of this transmission and the physical factors governing it remains lacking. Two key features of the actin cytoskeleton are its viscoelastic nature and the presence of prestress due to actomyosin motor activity. We develop a model of mechanical signal transmission through prestressed viscoelastic actin stress fibers that directly connect the cell surface to the nucleus. The analysis considers both temporally stationary and oscillatory mechanical signals and accounts for cytosolic drag on the stress fibers. To elucidate the physical parameters that govern mechanical signal transmission, we initially focus on the highly simplified case of a single stress fiber. The results demonstrate that the dynamics of mechanical signal transmission depend on whether the applied force leads to transverse or axial motion of the stress fiber. For transverse motion, mechanical signal transmission is dominated by prestress while fiber elasticity has a negligible effect. Conversely, signal transmission for axial motion is mediated uniquely by elasticity due to the absence of a prestress restoring force. Mechanical signal transmission is significantly delayed by stress fiber material viscosity, while cytosolic damping becomes important only for longer stress fibers. Only transverse motion yields the rapid and long-distance mechanical signal transmission dynamics observed experimentally. For simple networks of stress fibers, mechanical signals are transmitted rapidly to the nucleus when the fibers are oriented largely orthogonal to the applied force, whereas the presence of fibers parallel to the applied force slows down mechanical signal transmission significantly. The present results suggest that cytoskeletal prestress mediates rapid mechanical signal transmission and allows temporally oscillatory signals in the physiological frequency range to travel a long distance without significant decay due to material viscosity and/or cytosolic drag
Calpains Mediate Integrin Attachment Complex Maintenance of Adult Muscle in Caenorhabditis elegans
Two components of integrin containing attachment complexes, UNC-97/PINCH and UNC-112/MIG-2/Kindlin-2, were recently identified as negative regulators of muscle protein degradation and as having decreased mRNA levels in response to spaceflight. Integrin complexes transmit force between the inside and outside of muscle cells and signal changes in muscle size in response to force and, perhaps, disuse. We therefore investigated the effects of acute decreases in expression of the genes encoding these multi-protein complexes. We find that in fully developed adult Caenorhabditis elegans muscle, RNAi against genes encoding core, and peripheral, members of these complexes induces protein degradation, myofibrillar and mitochondrial dystrophies, and a movement defect. Genetic disruption of Z-line– or M-line–specific complex members is sufficient to induce these defects. We confirmed that defects occur in temperature-sensitive mutants for two of the genes: unc-52, which encodes the extra-cellular ligand Perlecan, and unc-112, which encodes the intracellular component Kindlin-2. These results demonstrate that integrin containing attachment complexes, as a whole, are required for proper maintenance of adult muscle. These defects, and collapse of arrayed attachment complexes into ball like structures, are blocked when DIM-1 levels are reduced. Degradation is also blocked by RNAi or drugs targeting calpains, implying that disruption of integrin containing complexes results in calpain activation. In wild-type animals, either during development or in adults, RNAi against calpain genes results in integrin muscle attachment disruptions and consequent sub-cellular defects. These results demonstrate that calpains are required for proper assembly and maintenance of integrin attachment complexes. Taken together our data provide in vivo evidence that a calpain-based molecular repair mechanism exists for dealing with attachment complex disruption in adult muscle. Since C. elegans lacks satellite cells, this mechanism is intrinsic to the muscles and raises the question if such a mechanism also exists in higher metazoans
Integrated omics analyses reveal the details of metabolic adaptation of Clostridium thermocellum to lignocellulose-derived growth inhibitors released during the deconstruction of switchgrass
Stile di vita e prevalenza di obesità , ipertensione e diabete in un campione di bambini, adolescenti e adulti. Lo studio ABCD
Live-cell 3D super-resolution imaging in thick biological samples
We demonstrate three-dimensional (3D) super-resolution live-cell imaging through thick specimens (50-150 \u3bcm), by coupling far-field individual molecule localization with selective plane illumination microscopy (SPIM). The improved signal-to-noise ratio of selective plane illumination allows nanometric localization of single molecules in thick scattering specimens without activating or exciting molecules outside the focal plane. We report 3D super-resolution imaging of cellular spheroids
Safety, tolerability, pharmacokinetics, and pharmacodynamics of a long-acting release (LAR) formulation of pasireotide (SOM230) in patients with gastroenteropancreatic neuroendocrine tumors: results from a randomized, multicenter, open-label, phase I study
Non-familial small bowel carcinomas in Crohn's disease: clinico-pathological, molecular and prognostic features
Background Primary non-ampullary small bowel adenocarcinoma (SBAs) is a remarkably rare tumor in the general population. Celiac disease (CD) is associated with an increased risk of developing SBA. Published data on the morphologic, phenotypic and molecular features of CD-associated SBAs (CD-SBAs) are very limited.
Design We analyzed 11 SBAs arisen in the setting of CD collected from four different Italian Institutions. Immunoreactions for intestinal markers (MUC2, CDX2, CD10) and for gastric markers (MUC5AC, MUC6) were performed on representative sections of each SBA. In all cases, non-tumoral small intestinal mucosa was also examined. Additionally, we investigated the frequency of KRAS, NRAS, and BRAF somatic mutations in 9 out of 11 cases.
Results The average age of patients was 56 years (rang 38-72) with predilection of females (9 females and 2 males). Three tumors were at stage III or IV and 1 patient died of disease after 6 months from diagnosis. One tumor was localized in the duodenum (second part), the remaining ten were in the jejunum. On histologic examination, three neoplasms were high grade poorly differentiated carcinomas (grade 3), one of which showing a poorly cohesive component with signet ring cells, while 8 were low-grade intestinal-type tubular adenocarcinomas. Ten cases were positive for CDX2, 7 for MUC2 and 7 for CD10. One case showed >5% MUC5AC-positive cells. No case had MUC6. Sequencing analysis of KRAS, NRAS, and BRAF hot spot regions revealed the presence of mutations only at codon 12 in exon 2 of KRAS in X of 9 cases. We found no mutations in the hot spot regions of NRAS (exons 2, 3, 4) or BRAF (exon 15).
Conclusion CD-SBAs appear to have a predilection for younger people (especially female) than other SBAs and may behave aggressively. Most CD-SBAs express structural and phenotypic patterns of intestinal differentiation, including CD10 (a marker of the enterocyte brush border). In about 30% of cases they can show a high grade histology. Unlike SBAs associated with Crohn’s disease, CD-SBAs seem to rarely express gastric markers