A Subpopulation of Synovial Fibroblasts Leads to Osteochondrogenesis in a Mouse Model of Chronic Inflammatory Rheumatoid Arthritis.

Specific major histocompatibility complex (MHC) class II genes result in a high susceptibility to rheumatoid arthritis (RA), with co-stimulatory molecules working together with MHC class II during the progression of the disease. To elucidate the involvement of the B7.1 co-stimulatory molecule in RA, we analyzed the phenotype of B7.

Definition of MHC and T cell receptor contacts in the HLA-DR4restricted immunodominant epitope in type II collagen and characterization of collagen-induced arthritis in HLA-DR4 and human CD4 transgenic mice.

Rheumatoid arthritis (RA) is an autoimmune disease associated with the HLA-DR4 and DR1 alleles. The target autoantigen(s) in RA is unknown, but type II collagen (CII) is a candidate, and the DR4- and DR1-restricted immunodominant T cell epitope in this protein corresponds to amino acids 261-273 (CII 261-273). We have defined MHC and T cell receptor contacts in CII 261-273 and provide strong evidence that this peptide corresponds to the peptide binding specificity previously found for RA-associated DR molecules.

Expression of HLA-DR4 and human CD4 transgenes in mice determines the variable region beta-chain T-cell repertoire and mediates an HLA-DR-restricted immune response.

Inherited susceptibility to rheumatoid arthritis is associated with genes encoding the human major histocompatibility complex class II molecule HLA-DR4. To study the immune function of HLA-DR4 and attempt to generate a murine model of rheumatoid arthritis we have produced triple transgenic mice expressing HLA-DRA*0101, -DRB1*0401, and human CD4. The expression of the HLA transgenes is driven by the promoter of the murine major histocompatibility complex class II I-E alpha gene and was found on murine cells that normally display major histocompatibility complex class II molecules.

Diffuse abdominal uptake of technetium-99m-methylene diphosphonate in a patient on continuous ambulatory dialysis during bone scintigraphy.

Extra-skeletal uptake of bone seeking radiopharmaceuticals has been documented by scintigraphy. We present a case of diffuse uptake of 99mTc-methylene diphosphonate (MDP) in the abdomen of a patient while undergoing continuous ambulatory peritoneal dialysis (CAPD) who had no symptoms or findings referable to the abdomen. We hypothesized that the 99mTc-MDP crossed the peritoneal membrane across a concentration gradient.

Rhinocerebral mucormycosis: a case report with magnetic resonance imaging findings.

Mucormycosis is a rare fungal disease most often encountered in patients who are diabetic, immunocompromised, severely burned, or who have a history of intravenous drug abuse. Intracranial presentation includes the isolated cerebral and the more common rhinocerebral forms. The computed tomography picture in mucormycosis is well documented.