Isolation and characterization of a distinct immunoregulatory isoform of alpha-fetoprotein produced by the normal fetus

In this report, we examine the functional significance of the molecular microheterogeneity of alpha-fetoprotein (AFP). In doing so, we have taken the direct approach of purifying the naturally occurring isomeric forms of fetal-derived AFP using a preparative anion exchange column linked to an automated fast protein liquid chromatography (FPLC) system followed by parallel testing of each isolated molecular variant for in vitro immunoregulatory activity. The data obtained demonstrate the presence of seven distinct variants of AFP as defined by their retention volumes on FPLC elution profiles, by their pIs on analytical IEF gels, and by Western blot analysis. Molecular mass determination by SDS-PAGE showed each isomer to be equivalent in size to 69,000-dalton native unfractionated AFP molecules. All the immunosuppressive activity of AFP was localized to a single variant representing only 6% of the total composition of native AFP. The immunoregulating isomer termed AFP-1 was the least acidic of the seven isolated variants with a pI of 5.1 and displayed a sialic acid content of 1 mol/mol of protein. The inhibitory activity of AFP-1 could be readily measured on T cell-dependent antibody synthesis, Con A-induced stimulation of Lyt-1+23- thymocyte DNA synthesis, and lymphokine-activated NK cell activity. All other isomers were without effect in these test systems. The immunosuppressive AFP-1 isomer also displayed the strongest growth-promoting influence on cultured bone marrow lymphocytes. There was no correlation between functional activity and degree of expression of sialic acid residues on the AFP molecules. These findings demonstrate that the immunoregulating function of AFP is confined to a distinct and relatively small subpopulation of native AFP molecules and should therefore contribute to the resolution of outstanding questions regarding the structure/function relationship of this onco-fetal glycoprotein.     

Common forefoot deformities. How to treat, when to refer

Initial assessment of common forefoot deformities by the primary care physician is quite feasible. A thorough history, examination of the foot with the patient standing and seated, assessment of the patient's footwear, and radiographic evaluation can often lead to gratifying relief with use of simple office measures. Even in cases that require referral to an orthopedic surgeon, interim relief of symptoms and the patient's increased awareness of the problem and its cause enhance the patient's understanding and the final outcome as well.     

ITI endosteal hollow cylinder implant systems

The endosteal hollow cylinder implant systems have been in clinical use for over 10 years. These systems incorporate advanced sophisticated biomaterials and bioengineering design concepts such as the titanium plasma spray (TPS) surface coating as well as the cylindric shape. This shape has now introduced the third dimension to dental implantology. In previous systems, such as the blade-vent, only height and width were present. Therefore, these previous systems could not be used as single-tooth replacements; also, they were not able to withstand lateral forces or torquing. In a series of cases reported from Switzerland, Sweden, Germany, and the United States, 580 hollow cylinder implants were placed for up to 10 years with an overall rate of success of 95.3 per cent.     

Three different pathogenic mechanisms for paraparesis in association with bacterial infections

Three different pathogenic mechanisms are apparent for paraparesis in association with a bacterial infection: a spinal cord compression caused by either an epidural abscess or a vertebral collapse due to spondylitis, an ischaemic spinal cord lesion as a result of septic thromboembolus in abdominal aorta, and a nonspecific, probably immunological, cause in association with reactive polyarthritis. An example of each of these mechanisms is described by means of case histories.     

The late results after axillo-femoral bypass grafts in patients with leg ischaemia

The late results--up to six years--after axillo-femoral bypass reconstruction are reported for 85 patients with leg ischaemia who were regarded as poor-risk patients for aortic bypass surgery, or who had aortic graft infection. Velour-Dacron grafts and expanded polytetrafluoroethylene (PTFE, Gore-Tex)--grafts have been used. The cumulative patency rate (life table) six years after graft implantation was 64% (PTFE-grafts) and 58% (Velour-Dacron grafts). The corresponding cumulative limb salvage rate six years after graft implantation was 88% when PTFE grafts were used and 77% when Velour-Dacron grafts were used. Our results demonstrate that axillo-femoral reconstruction is a useful procedure with a good patency rate 6 years after implantation. This procedure should be considered when dealing with poor risk patients with severe leg ischaemia.