YNOVIAL MEMBRANE lining cells show acid phosphatase activity in S granules that are thought to be lysosomes.' In rheumatoid arthritis, the lining cells show markedly increased acid phosphatase activity.' This observation led us to compare acid phosphatase activity in synovial fluids from normal and arthritic joints with the thought that in rheumatoid arthritis, lysosome of lining cells might release their contained hydrolytic enzymes into synovial effusions. There appears to be no previous study of the occurrence of acid phosphatase in synovial fluid, although activities of a number of other enzymes have been measured: glucuronidase,2 pepsin and trypsin? amylase and lipase,' peroxidase,s alkaline phosphatase and transaminases8 METHODSPatients in the following groups were studied: 1) "Normal" subjects were those apparently free of joint disease. This group included Acid phosphatase (AP) activity was measured in synovial fluid from the knee, and in serum obtained at the same time. Three pleural fluids and three cerebrospinal fluids were also studied. All determinations were done within 30-60 minutes. The method of Andersch and Sczapinskis was used with paranitrophenyl phosphate (Sigma) as substrate. By this method the maximum normal level of serum AP is 0.63 units for males and 0.56 units for females.Cell counts and differential counts were carried out on synovial fluids within three hours after collection. Protein and hyaluronate determinations were done on most synovial fluids using methods described e1sewhere.S RESULTSOf six "normal" synovial fluids studied, four showed AP levels within normal limits, and two showed elevation of AP twice the maximum normal adult

Inflammatory mediators such as interferon-gamma (IFN-gamma) are known to induce the expression of class II HLA (HLA-DR) and intercellular adhesion molecule 1 (ICAM-1) in a variety of cell types including epithelial cells. The coexpression of ICAM-1 and HLA-DR has been implicated in the pathogenesis of immune mediated ocular disease. We investigated the expression of ICAM-1 on the ocular surface of the rat eye following subconjunctival administration of IFN-gamma. A dose response study was performed using 100, 1,000 and 10,000 IU IFN-gamma/dose. The presence of ICAM-1 was determined using a standard immuno-peroxidase staining technique. The cornea, limbus, and conjunctiva were evaluated. The degree of reaction product in each area was graded by a masked observer. We found constitutive expression of ICAM-1 on the conjunctiva but not on the cornea. There was a significant relationship between the dose of IFN-gamma and the intensity of ICAM-1 staining on the conjunctiva (p < or = 0.05) and on the limbus (p < or = 0.04). Subconjunctival IFN-gamma had no effect on the expression of ICAM-1 in the cornea.

No abstract

Creation of a fracture in a reservoir of design length and conductivity requires that the assumptions supporting the design be valid a ted in the field and the fracture redesigned if necessary. The tools and methods available to undertake this validation are simple and effective, minimizing risk of premature sandoff or inadequate fracture length and conductivity. A recommended practice for use in the effective execution of hydraulic fracture treatments is presented.