752 research outputs found
Studies on ESR Spectra of Some Polyamine-Cu(II) Complexes In Solution & Frozen Solution
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Neural network implementation for the prediction of load curves of a flat head indenter on hot aluminum alloy
The indentation test performed by means of a flat-ended indenter is a valuable non-destructive method for assessment of metals at a local scale. Particularly, from the indentation curves it is possible to achieve several mechanical properties. The aim of this paper is the implementation of an artificial neural network for the prediction of the indentation load as a function of the penetration depth for an aluminium substrate. In particular, the neural network is addressed to the mechanical characterization of the bulk in function of temperature and indentation rate. The results obtained showed a high accuracy in curves prediction
Erdheim-Chester disease : from palliative care to targeted treatment
Erdheim-Chester disease (ECD) is a life-threatening multi-systemic non-Langerhans histiocytosis with cardiovascular complications as the leading cause of death. ECD affects the kidneys in up to 30% of cases, with fibrotic tissue deposition in the perirenal fat and renal hilum. Diagnosis is usually based on histological analysis of the pathologic tissue, which typically shows xanthogranulomatous infiltrates of foamy CD68+/CD1a-histiocytes surrounded by fibrosis. A consistent percentage of patients affected by ECD develop renal failure and hypertension as a consequence of renal artery stenosis and hydronephrosis. These conditions have been generally treated with the placement of stents and nephrostomies that frequently led to disappointing outcomes. Before the introduction of interferon-alpha (IFN\u3b1) treatment, the mortality rate was as high as 57% in the long term. Recent studies have granted new insights into the pathogenesis of ECD, which seems to bear a dual component of clonal and inflammatory disease. These advances led to use specific therapies targeting either the oncogenes (BRAFV600E) or the effectors of the immune response implicated in ECD (IL-1, TNF\u3b1). Drugs such as anakinra (recombinant human IL-1 receptor antagonist), infliximab (monoclonal antibody against TNF\u3b1) and vemurafenib (inhibitor of mutant BRAF) showed promising results in small single-centre series. Although larger trials will be needed to address the impact of these drugs on ECD prognosis and to select the most effective treatment, targeted therapies hold the premises to drastically change the outcome of this condition. \ua9 2014 The Author
Reversible acute renal failure from gross haematuria due to glomerulonephritis: not only in IgA nephropathy and not associated with intratubular obstruction
Seven patients with acute renal failure due to gross haematuria caused by glomerulonephritis are described. Gross haematuria lasting 4-40 days led to acute impairment of renal function of variable severity (peak plasma creatinine 1.3-12 mg/dl) and duration. While partial recovery of renal function occurred in all patients within few days, complete remission was observed only some months later. Three patients had IgA nephropathy (2 the primary form and 1 nephritis secondary to Schönlein-Henoch purpura), two patients had acute postinfectious glomerulonephritis, andtwo others had focal necrotizing (pauci-immune) glomerulonephritis. The glomerular changes seen in renal biopsy were not enough to explain per se the renal function impairment. Tubular changes, however, were severe and consisted of tubular necrosis, erythrocyte casts, erythrocyte phagocytosis by tubular cells, accompanied by interstitial damage (oedema, red-cell extravasation, and inflammatory infiltrates). Study of the renal biopsies by immunofluorescence revealed retrodiffusion of Tamm-Horsfall protein into the glomerular Bowman's space, a sign of obstructed tubular flow in any case. It is concluded that acute renal failure due to gross haematuria in glomerulonephritic patients may not occur only in IgA nephropathy, as reported so far, and is not associated with intratubular obstructio
Springback control in laser-assisted bending manufacturing process by using a fuzzy uncertain model
Ureteral endometriosis: a rare and underdiagnosed cause of kidney dysfunction
Little attention has been paid by the renal literature to ureteral endometriosis, a rare and silent disorder that can eventually lead to renal failure. In endometriosis, the ureteral involvement can be limited to a single ureter, more often the left one, or both ureters with consequent urine tract obstruction and ureterohydronephrosis. In most cases, the ureteral obstruction is caused by endometrial tissue surrounding the ureter (extrinsic ureteral endometriosis). In the remaining cases, endometrial cells are located within the ureter (intrinsic ureteral endometriosis). Progressive ureteral obstruction can be insidious in onset and can ultimately lead to renal failure if a correct diagnosis is missed. The true incidence of renal failure caused by endometriosis is completely unknown, although cases have been reported in the literature. The diagnosis of ureteral endometriosis is difficult since the disease may be clinically silent or associated with non-specific symptoms. Only a high index of suspicion and radiological support may help to obtain an early diagnosis. However, while renal imaging is useful in the cases of extrinsic endometriosis, the diagnosis of intrinsic endometriosis often requires ureteroscopy or laparoscopy. The prognosis of ureteral endometriosis depends on the time of diagnosis. In too many cases of bilateral obstruction, the patient is referred to the nephrologist because of an advanced, irreversible renal failure. Although some patients may benefit from progestin or anti-arotamase therapy, in most cases of ureteral endometriosis surgery is needed, laparoscopy surgery being preferred today to laparatomy
Study of the laser-material interaction for innovative hybrid structures: Thermo-mechanical characterization of polyethylene-based polymers
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