Myocardial positron computed tomography with 13N-ammonia at rest and during exercise

To assess the value of myocardial-perfusion positron computed tomography (PCT) for the evaluation of coronary artery disease (CAD), ¹³N-ammonia PCT using a whole-body multislice PCT device was performed at rest and during exercise in 6 normal subjects and 19 patients with angiographically documented CAD. The ¹³N-ammonia distribution in the myocardium was assessed both qualitatively and quantitatively. At rest and during exercise, the tracer distribution was homogeneous in the 6 normal cases. In the 19 patients with CAD, regional hypoperfusion was observed in 14 cases (74%) at rest and in 18 cases (95%) during exercise. Additional perfusion abnormalities were detecting during exercise in 12 cases. Segmental analysis of the myocardial perfusion identified 30 out of 34 stenosed vessels (88%) during exercise, with only one false-positive finding of diseased vessels (specificity, 98%). For the quantitative analysis of myocardial perfusion by PCT, the percentage of change in the tracer concentration in the same region between the rest and stress images was calculated. The concentration was slightly increased in normal myocardial segments (14.4%±5.8%; P<0.001), whereas in CAD, it was significantly decreased in segments with stenosed vesels (-18.0%±18.3%; P<0.02). We conclude that ¹³N-ammonia PCT at rest and during exercise provides highquality images, and is a sensitive and effective technique for detecting CAD and identifying individual stenosed vessels. Furthermore, this technique makes possible quantitative assessment of the coronary reserve function.     

Quantitative evaluation of tricuspid regurgitation by digital simulation of cardiac time-activity curves

To estimate tricuspid regurgitation (TR) quantitatively, a curve fitting method by computer has been employed. Transport in the right cardiac chambers after intravenous bolus injection of macro-aggregated albumin labeled with technetium 99m (^99mTc-MAA) was recorded in anterior view by a gammacamera system. Disturbance of the dilution curves from the left heart can be avoided by using ^99mTc-MAA injection. To know the radioisotope activity during the transport, time-activity curves are recorded for the superior vena cava, right atrium, and right ventricle. Parametric differential equations, obtained from compartmental analysis, interpret these curves mathematically.The rate of regurgitation is determined by comparison, using an iterative process, between the original and simulated curves. The whole process is performed automatically by computer. The calculated regurgitation value correlated well with the value from the analog simulation. The method clearly separated those with TR from those without TR.This digital simulation for estimating parameters using a compartmental model is a feasible tool in detecting and quantifying TR.     

Effects of periodontopathic bacteria on IL-1 and IL-1 inhibitor production by human polymorphonuclear neutrophils

The effect of heat-killed periodontopathic bacteria on the production of interleukin-1 (IL-1) and an IL-1 inhibitor by human polymorphonuclear neutrophils (PMN's) was examined. Peripheral blood was obtained from 18 healthy volunteers and the PMN's were separated using dextran sedimentation and Ficoll-Paque density gradient centrifugation. The PMN's (5 x 10(5) cells/well) were cultured in serum-free media with or without heat-killed periodontopathic bacteria. Four gram-negative periodontopathic bacteria were used; Bacteroides gingivalis FDC 381, Bacteroides forsythus FDC 338, Actinobacillus actinomycetemcomitans Y4 and Fusobacterium nucleatum FDC 263. The non-oral Fusobacterium mortiferum ATCC 25557 was used as a control organism. IL-1 activity was assayed using thymocyte proliferation. The non-oral organism F. mortiferum stimulated IL-1 production by PMN's, in contrast none of the periodontopathic bacteria stimulated IL-1 release although the bacteria themselves had an IL-1 enhancing effect. Following fractionation of the periodontopathic bacteria stimulated PMN supernatants, an IL-1 inhibitory fraction was identified. These results may illustrate a further mechanism by which periodontopathic bacteria may evade the protective effect of PMN's and may also suggest a regulatory role for PMN's in chronic inflammatory periodontal disease.     

Pneumocystis carinii pneumonia in renal transplant recipients treated with cyclosporin

Four cases of pneumocystis carinii pneumonia occurred among 38 renal transplant recipients. Diagnosis was confirmed by cyst concentration technique in 2 cases. The other 2 cases were clinically, from the rapid improvement of fever, pulmonary infiltrates and hypoxia following a therapeutic trial of high dose sulfamethoxazole-trimethoprim. All patients responded to treatment with high dose sulfamethoxazole-trimethoprim. Three patients survived pneumocystis carinii pneumonia, but i died due to aspergillosis. One patients showed serological evidence of concomitant cytomegalovirus infection.     

Subunit b of factor XIII is present in bovine platelets

Distribution of B subunit of coagulation factor XIII( FXIII B ) in bovine platelets was determined. Intracellular location of FXIII B in platelets was confirmed by fluorescent antibody technique. Positive staining of FXIII B was observed with Triton-permeabilized platelets but not with non-permeabilized platelets. Immunoblots of plasma and platelet lysate revealed that the antibody was specific for FXIII B and this antigen existed in the supernatant of sonication-solubilized platelets. The mount of FXIII B in platelets was determined to be 17.3 ± 6.7 ng/10⁸ platelets by radioimmunoassay. This is the first visual and quantitative demonstration of intracellular FXIII B.     

Identification of axon terminals of the cerebello-olivary fibers in the cat: an electron microscope study using the anterograde horseradish peroxidase method

After injection of horseradish peroxidase (HRP) into the lateral cerebellar nucleus of the cat, axon terminals containing electron-dense HRP-granules were identified contralaterally within the principal olive. These terminals contained spherical synaptic vesicles, and made asymmetrical synaptic contacts with dendritic profiles of small or medium size.     

Translateral retroperitoneal approach in radical surgery for pancreatic caricinoma

Investigations of the lymphatic routes using dye during operations and histological studies on the resected specimen of the pancreas and autopsied cases with pancreatic carcinoma have led to the conclusion that the surgery should be performed more extensively to improve the results and should consist of a complete lymphatic excision surrounding the celiac axis and the trunk of the superior mesentric artery including dissection of the nerve plexus and wide retroperitoneal dissection surrounding the pancreas, upwards to the level of adrenal glands, and downwards to the level of iliac bifurcation. A translateral retroperitoneal approach was found to be the most useful and safe method for such extended resection in patients with pancreatic carcinoma. Our radical procedure for pancreatic carcinoma is described herein.