Bone marrow transplantation in dogs after radio-ablation with a new Ho-166 amino phosphonic acid bone-seeking agent (DOTMP).

beta-emitting 166Ho (t1/2 = 26.78 hours, E(beta)max = 1.8 MeV) complexed with the phosphonic acid chelator, 1,4,7,10 tetraazacyclododecane-1,4,7,10-tetra(methylene phosphonic acid) (DOTMP) at a ligand-to-metal ratio of 1.5:1 binds to bone. This radioactive complex is a marrow-ablating radiopharmaceutical that appears useful for preparation of bone marrow (BM) transplant recipients without the morbidity usually associated with total body irradiation preparatory regimens. We have found with seven splenectomized young adult beagle dogs that a 166Ho radiopharmaceutical dosage of 370 MBq/kg body weight provides an initial skeletal radioactivity burden of at least 1.5 GBq/kg skeleton and results in complete ablation of hematopoietic marrow cell populations within 7 days. The beta particle flux distribution in BM-forming skeletal tissue is not uniform. Red marrow radiation doses varied from 30 to 115 Gy as estimated by direct radioassay and autoradiographic analyses of both bone biopsies and postmortem samples; the median value of 61 Gy agreed with our theoretical expectations. In vivo radioactivity distribution was evaluated with nuclear imaging methods. Apparently, normal hematopoiesis was restored in three dogs with autologous BM transplants performed 5 to 6 days after administration of the marrow ablative radiopharmaceutical, 166Ho-DOTMP. BM biopsies at 7 to 10 months posttransplantation indicate continued normal hematopoietic activity.

Osteomyelitis of the axial border of the proximal sesamoid bones in seven horses.

Destructive lesions of the axial region of the proximal sesamoid bones were identified by radiography in eight fetlocks and seven lame adult horses. Lameness ranged from 2 to 5 (mean 4; scale 1 to 5) at the time of examination, with a duration of 10 days to two years (mean 5.6 months). Destructive lesions involved both proximal sesamoid bones when examined radiographically and were situated primarily at the level of the mid-body and apical region of the axial borders. Some lesions were cystic, whereas others eroded the axial border more diffusely. Scintigraphy revealed markedly increased activity within the proximal sesamoid bones of the clinically lame limb of four of the five horses examined. In four horses, post mortem computed tomography revealed axial border bone destruction and cavitary lesions within cancellous bone of affected proximal sesamoid bones. Lesions seen by computed tomography were larger than those identified on radiographic examination. Cavitary lesions not seen radiographically were identified in the proximal sesamoid bones of two clinically unaffected fetlocks examined for comparison in two of the seven horses. Evidence of acute, subacute or chronic/reparative osteomyelitis of the axial region of the proximal sesamoid bones was seen in the 10 fetlocks identified as abnormal from radiography or computed tomography. Also, three horses had septic synovitis of the flexor sheath of the clinically affected limb; of these, two had septic arthritis of the fetlock joint.

[Quantitative analysis of the electromyogram using triggered correlation]. / Quantitative Analyse des Elektromyogramms mittels der getriggerten Korrelation.

A study has been made to determine the usefulness of triggered correlation as a method of automatic quantitative analysis of graphic representations of the somatic electric currents associated with muscular action. Although an electromyogram is neither a normally distributed nor a stationary random process, the method has been found to be suitable for clinical electromyography. The method is easy to use, with measuring values that may be used for diagnostic purposes being obtained within a few seconds. In the case of normal subjects and patients with neuromuscular diseases, parameters of triggered correlograms are compared with those of visuamanually analyzed or digitally averaged potentials of individual motor units.