Renal Behçet's Disease: An Update

PubMed ID: 18221990Objective: The aims of this study are (1) to report 33 patients with Behçet's disease (BD) having various renal manifestations, and (2) to update current data using our patients and published papers about BD and renal manifestations. Methods: The PubMed database was searched using the terms BD or Behçet's syndrome. We found reports of 94 patients (including ours) with BD and specific renal diseases (amyloidosis, 39; glomerulonephritis [GN], 37; renal vascular disease, 19; interstitial nephritis, 1). Results: The presentation of renal disease was edema/nephrotic syndrome in 12 patients (36%). Renal disease was incidentally diagnosed by routine urine analysis and measurement of serum creatinine level in 20 patients (61%). Renal failure was present in 23 patients (70%) and 5 of them have had cyclosporine treatment. The frequency of renal disease among BD patients has been reported to vary from less than 1 to 29%. Conclusions: The clinical spectrum of renal BD shows a wide variation. Amyloidosis (AA type), GN, and macroscopic/microscopic vascular disease are the main causes of renal BD. Patients with vascular involvement have a high risk of amyloidosis and amyloidosis is the most common cause of renal failure in BD. Several types of glomerular lesions are seen in BD. Current treatment options for renal BD are not evidence based. Radiological vascular intervention combined with immunosuppressive drugs can be useful in selected cases. Routine urine analysis and measurement of serum creatinine level are needed for early diagnosis of renal BD. © 2008 Elsevier Inc. All rights reserved

Frictional receding contact problem for a graded bilayer system indented by a rigid punch

The frictional receding contact problem for two graded layers pressed by a rigid punch is considered in this paper. The punch is subjected to both normal and tangential loads thereby resulting in frictional contact with the upper layer. It is also assumed that the contact between the layers is frictional and the lower layer is fixed. It is further assumed that the gradation in the layers follows an exponential variation through the thickness with different profiles while Poissons ratios are taken as constants. Using standard Fourier transform, the contact problem is converted to a system of two singular integral equations in which the contact pressures and the contact widths are the unknowns. The integral equations are then solved numerically using Gauss–Jacobi integration formula. The Finite Element Method was additionally employed and both exponential and power law material gradation is used to solve the investigated problem and the obtained numerical and analytical results are in good agreement. The primary intention of this paper is to investigate the effect of material gradation, friction coefficients, layers thicknesses and material property mismatch at the interface between the layers on the contact pressures and contact widths. © 2018 Elsevier Lt