ABSTRACT
La amiloidosis asociada a diálisis es una patología causada por depósito de fibrillas amiloides constituidas por la proteína beta 2 microglobulina1-5. Es una complicación seria y excepcional que ocurre en pacientes sometidos a hemodiálisis de larga data. El caso que presentamos corresponde a un paciente de 56 años en hemodiálisis hace 36 añ os, con amiloidosis del conducto auditivo externo bilateral. Sólo 13 casos de amiloidosis en el conducto auditivo externo, incluido éste han sido reportados en la literatura66-14. Este corresponde al tercercaso de amiloidosis asociada a diálisis del conducto auditivo externo reportado en la literaturaf6,10.
Dialysis related amyloidosis is a disorder caused by deposition of amyloid fibrils formed by beta-2 microglobulin1-5. It is a serious and exceptional complication in patients undergoing longterm hemodialysis. The present case involved a 56 years old man who had been on hemodialysis for 36 years with bilateral amyloidosis of the external auditory canal. Only 13 cases of amyloidosis in the ear canal, including the present case have been reported in the literature66-14. This is the third reported case of dialysis related amyloidosis of the ear canal6,10.
Subject(s)
Humans , Male , Middle Aged , Renal Dialysis/adverse effects , Ear Diseases/etiology , Amyloidosis/etiology , Tomography, X-Ray Computed , Long-Term Care , Ear Canal/surgery , Ear Diseases/surgery , Ear Diseases/diagnosis , Amyloidosis/surgery , Amyloidosis/diagnosis , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/therapyABSTRACT
The study was performed to detect the binding proteins for advanced glycation end products (AGEs) on human joint synovial cells (HSCs). Normal human synovial cells (type A and type B cells) were isolated and cultured in vitro. Binding assay was performed with radiolabeled human serum albumin modified by AGE (AGE HSA). Specific binding was defined as total binding minus binding in the presence of excess unlabeled AGE HSA. The result showed that: specific dose dependent binding of 125 I AGE HSA to immobilized HSCs was observed with R=4.90 0.75 10 4 /cell , Kd = 1.27 0.19 10 -6 M in type A HSCs , and R= 3.48 0.32 10 5 /cell, Kd= 1.38?0.16 10 -7 M in type B HSCs. TNF ?,IL 1? and AGE HSA upregulated the expression of AGE binding proteins on HSCs. Normal HSCs express specific AGE binding proteins. TNF ?, IL 1? and AGE HSA upregulate the expression of these proteins, suggesting that joint resident cells may be involved in the pathogenesis of dialysis related amyloidosis.
ABSTRACT
Objective To test the hypothesis that attachment of synovial cell to &?2-microglobulin modified with advanced glycation end products (ACE-?2m) would affect cell adhesion, spreading and proliferation.Methods Normal human synovial cells (type B cells) were isolated and plated in culture dishes coated with AGE-?2m or with normal extracellular matrix proteins (EMP). Adhesion was analyzed by counting the isotope-labelled cells. Spreading was tested using a light microscope and proliferation determined by 3H-TdR incorporation and counting the number of cells. Results Synovial cells adhered less effectively to AGE-?2m, ?2m and AGE-collagen than to the normal EMP (collagen and fibronectin). Cells interacting with AGE-?2m, ?2m or AGE-collagen also demonstrated less extensive spreading throughout the examined time intervals (60-120 minutes after plating), and decreased 3H-TdR incorporation and cell numbers after 72 hours of plating when compared to cells interacting with normal EMP. Conchusion AGE-?2m in amyloid may alter synovial cell behavior in situ in ways which cods contribute to the development of dialysis-related amyloidodsis(DRA).