319 research outputs found
Gnss and photogrammetric uav derived data for coastal monitoring: A case of study in emilia-romagna, italy
GNSS real-time techniques and UAV photogrammetry can be alternative methods for the monitoring of sand beaches. This activity is particularly important in environments such as the Emilia-Romagna coastline. In this paper, two couples of surveys (year 2019 and 2020) performed using GNSS or a low-cost UAV equipment over a common area were compared in order to analyse: point-wise height differences, profile shapes along defined sections, and volumes variations over time. Both surveys were aligned to the same reference benchmark through GNSS measurements. The highest discrepancies between the two surveying methods (tens of cm) were found in vegetated areas and along the shoreline, otherwise, the height differences are mainly within the 10 cm level. In terms of volumes, excluding the most critical areas, differences close to zero can be found. Obtained results show that GNSS and UAV photogrammetry provides similar results, at least for quite flat terrains and when decimetre-level accuracy is required
Pomegranate juice reduces oxidized low-density lipoprotein downregulation of endothelial nitric oxide synthase in human coronary endothelial cells
We examined the hypothesis that pomegranate juice (PJ) can revert the potent downregulation of the expression of endothelial nitric-oxide synthase (NOSIII) induced by oxidized low-density liporotein (oxLDL) in human coronary endothelial cells. Western blot and Northern blot analyses showed a significant decrease of NOSIII expression after a 24-h treatment with oxLDL. Accordingly, we observed a significant dose-dependent reduction in nitric oxide bioactivity represented by both basal and bradykinin-stimulated cellular cGMP accumulation. These phenomena were corrected significantly by the concomitant treatment with PJ. Our data suggest that PJ can exert beneficial effects on the evolution of clinical vascular complications, coronary heart disease, and atherogenesis in humans by enhancing the NOSIII bioactivity
Nitric oxide and atherosclerosis: an update
Nitric oxide (NO) is a molecule that has gained recognition as a crucial modulator of vascular disease. NO has a number of intracellular effects that lead to vasorelaxation, endothelial regeneration, inhibition of leukocyte chemotaxis, and platelet adhesion. Endothelium damage induced by atherosclerosis leads to the reduction in bioactivity of endothelial NO synthase (eNOS) with subsequent impaired release of NO together with a local enhanced degradation of NO by increased generation of reactive oxygen species with subsequent cascade of oxidation-sensitive mechanisms in the arterial wall. Many commonly used vasculoprotective agents have their therapeutic actions through the production of NO. L-Arginine, the precursor of NO, has demonstrated beneficial effects in atherosclerosis and disturbed shear stress. Finally, eNOS gene polymorphism might be an additional risk factor that may contribute to predict cardiovascular events. However, further studies are needed to understand the possible clinical implications of these correlations
To Learn or Not to Learn Features for Deformable Registration?
Feature-based registration has been popular with a variety of features
ranging from voxel intensity to Self-Similarity Context (SSC). In this paper,
we examine the question on how features learnt using various Deep Learning (DL)
frameworks can be used for deformable registration and whether this feature
learning is necessary or not. We investigate the use of features learned by
different DL methods in the current state-of-the-art discrete registration
framework and analyze its performance on 2 publicly available datasets. We draw
insights into the type of DL framework useful for feature learning and the
impact, if any, of the complexity of different DL models and brain parcellation
methods on the performance of discrete registration. Our results indicate that
the registration performance with DL features and SSC are comparable and stable
across datasets whereas this does not hold for low level features.Comment: 9 pages, 4 figure
Emergence of a non trivial fluctuating phase in the XY model on regular networks
We study an XY-rotor model on regular one dimensional lattices by varying the
number of neighbours. The parameter is defined.
corresponds to mean field and to nearest neighbours coupling. We
find that for the system does not exhibit a phase transition,
while for the mean field second order transition is recovered.
For the critical value , the systems can be in a non
trivial fluctuating phase for whichthe magnetisation shows important
fluctuations in a given temperature range, implying an infinite susceptibility.
For all values of the magnetisation is computed analytically in the
low temperatures range and the magnetised versus non-magnetised state which
depends on the value of is recovered, confirming the critical value
YY1 overexpression is associated with poor prognosis and metastasis-free survival in patients suffering osteosarcoma
<p>Abstract</p> <p>Background</p> <p>The polycomb transcription factor Yin Yang 1 (YY1) overexpression can be causally implicated in experimental tumor growth and metastasization. To date, there is no clinical evidence of YY1 involvement in outcome of patients with osteosarcoma. Prognosis of osteosarcoma is still severe and only few patients survive beyond five years. We performed a prospective immunohistochemistry analysis to correlate YY1 immunostaining with metastatic development and survival in a selected homogeneous group of patients with osteosarcoma.</p> <p>Methods</p> <p>We studied 41 patients suffering from osteosarcoma (stage II-IVa). Multivariate analysis was performed using Cox proportional hazard regression to evaluate the correlation between YY1 expression and both metastasis development and mortality.</p> <p>Results</p> <p>YY1 protein is not usually present in normal bone; in contrast, a high number of patients (61%) showed a high score of YY1 positive cells (51-100%) and 39% had a low score (10-50% positive cells). No statistical difference was found in histology, anatomic sites, or response to chemotherapy between the two degrees of YY1 expression. Cox regression analysis demonstrated that the highest score of YY1 expression was predictive of both low metastasis-free survival (HR = 4.690, 95%CI = 1.079-20.396; p = 0.039) and poor overall survival (HR = 8.353, 95%CI = 1.863-37.451 p = 0.006) regardless of the effects of covariates such as age, gender, histology and chemonecrosis.</p> <p>Conclusion</p> <p>Overexpression of YY1 in primary site of osteosarcoma is associated with the occurrence of metastasis and poor clinical outcome.</p
TEVAR for traumatic thoracic injury with the first-generation stent graft
Thoracic endovascular aortic repair (TEVAR) is a life-saving treatment for blunt thoracic aortic injury. We report long-term outcomes of two young patients who underwent TEVAR for blunt thoracic aortic injury with first-generation thoracic stent grafts. The off-label use of the endograft affected the outcomes: one case of open surgery conversion due to an aortoesophageal fistula and one case of endovascular relining for a voluminous pseudoaneurysm associated with a type III endoleak. Long-term follow-up is crucial in TEVAR, especially in case of a first-generation device used in an urgent setting
Case report: coeliac disease as a cause of secondary failure of glibenclamide therapy in a patient with permanent neonatal diabetes due to KCNJ11/R201C mutation
Type 1A Endoleak after TEVAR in the Aortic Arch: A Review of the Literature
Aortic arch repair is a challenging intervention. Open surgical repair is still considered the gold standard, but in high-risk patients, it is not always a reasonable option, making endovascular approaches an enticing, when not the only available, alternative for treatment. The strategies more commonly adopted are surgical supra-aortic trunk (SAT) rerouting followed by deployment of a standard thoracic endoprosthesis, chimney techniques, custom-made scalloped, fenestrated, and branched devices, and in situ or physician-modified fenestrations. If we excluded techniques involving SAT rerouting where the arch anatomy is surgically modified in order to make deployment in the aortic arch of a standard thoracic endoprosthesis possible, in the other techniques, one or more SATs are incorporated in the thoracic endoprosthesis. In these cases, no matter what solution is adopted, because of the morphology of the aorta at this level, achieving an ideal sealing is extremely difficult, and endovascular treatments of the arch are burdened by an increased risk of type IA endoleaks. PubMed, EMBASE, and Cochrane Library were searched. We identified 1277 records. After reading titles, abstracts, and full texts, we excluded 1231 records. Exclusion criteria were low-quality evidence, abstracts, case reports, conference presentations, reviews, editorials, and expert opinions. A total of 48 studies were included, for a total of 3114 patients. A type IA endoleak occurred in 248 patients (7.7%) with a mean incidence of 18.8% in chimney procedures, 4.8% and 3%, respectively, in fenestrated and branched devices, and 2.2% in in situ fenestration. We excluded from our analysis scalloped technology that is used when the target vessel originates from a healthy landing zone and represents a different anatomical setting. Type IA endoleaks are a concern with all types of endovascular aortic arch repair, and they can compromise the outcomes of the procedure. The rate of type IA endoleaks appears to be significantly higher in chimney procedures. In order to maximize sealing, whenever possible, endovascular repair of the arch should be achieved with custom-made fenestrated devices. However, chimney configurations are still a valuable solution particularly in the emergency setting, although in such a procedure, to guarantee accurate postoperative management and follow-up, an imaging protocol could be useful
Splenic artery transposition for hepatic arterial reconstruction in a locally advanced pancreatic cancer: A case report and literature review
OBJECTIVE: During pancreatic surgery for malignancies, hepatic revascularization is needed in case of en bloc resection with hepatic artery involvement. In these cases, the use of the splenic artery is described in the literature, including transposition and interposition techniques. PATIENTS AND METHODS: We report the case of pancreatic cancer resection with involvement of the right hepatic artery, anomalous arising from the superior mesenteric artery, and hepatic revascularization with splenic artery reconstruction. A literature review to analyze the use of splenic artery in hepatic revascularization during pancreatic cancer surgery was performed. RESULTS: A 61-year-old man with a 55-mm hypovascular tumor in the pancreatic head, in wide contact with the right hepatic artery, underwent total pancreatectomy and splenectomy. Right hepatic artery was resected, and the distal part of the splenic artery was transposed to the right hepatic artery with a termino-terminal anastomosis. Histopathological examination revealed R0 resection. CONCLUSIONS: Hepatic revascularization with splenic artery should be considered in patients suitable to extend resectability in pancreatic cancer surgery. A multidisciplinary approach and careful pre-operative planning are essential
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