Takashi Nakadera

Application of high-resolution scanning electron microscopy to biological macromolecules

The development of ultrahigh‐resolution scanning electron microscopes (SEMs) has made the observation of biological macromolecules feasible, but adequate preparation methods have not yet been established. Although it has been possible to observe some molecules after they have been spread on a carbon substrate, this method has not proved suitable for other molecules which exhibit lower contrast, or are more susceptible to damage by the electron beam. In this study we have applied heavy‐metal impregnation methods using phosphotungstic acid, uranyl acetate, or osmium tetroxide mordanted by tannic acid. In addition, contamination due to the electron beam was reduced by improving the vacuum in the specimen chamber, and by the use of a heated specimen stage. Using these measures, haemocyanin, ferritin, apoferritin, thyro‐globulin and immunoglobulin M were successfully imaged. Ultrahigh‐resolution SEM seems likely to become an important means for studying the morphology of biological macromolecules.

A Follow-Up Study of Uncemented Total Knee Arthroplasty (MG I) in Rheumatoid Arthritis

23 primary uncemeneted total knee arthroplasties (MG I) were performed in 16 patients with rheumatoid arthritis. Average age at the time of surgery was 60.3 years. Average duration of the disease was 10.4 years. The follow up period averaged 7.3 years (range, 5 to 10 years). Clinical evaluation based on the Japanese Orthopedic Association (JOA) score indicated significant improvement in pain from preoperative to the most recent follow-up examination. One knee required revision surgery due to metalosis of the patellar component after 7 years. There was no evidence of roentogenographic failure in femoral and tibial components. These medium term results suggest that uncemented TKA may be successful in rheumatoid knees. However, longer follow-up periods will be necessary for problems of patellar component in MG I TKAs, because 4 knee had progressive lateral shift of the patella.

Multiple Orerations of the Lower Extremities in Rheumatoid Arthritis

Seventy-two patients with rheumatoid arthritis treated by multiple joint operations of no less than 2 joints including a total joint arthroplasty were clinically reviewed. Average age of patients was 58.1 years at the time of initial operation. Average duration of contraction of the disease was 9.7 years. Function of the lower extremities was well maintained or improved in cases of two joint operations. Mutilating diseases (Ochis classifications) tended to have multiple joint operations with a deterioration in quality of life. The timing of multiple joint operations is most important especially in mutilating diseases. For maintaining the high quality of life of rheumatoid arthritis patients, it is necessary to diagnose the type of diseases at an early stage and to perform the operative treatment before the occurrence of severe bone destruction or joint instability under positive drug therapy.