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E Henze

Publications and source records attributed to E Henze.

At least 145 records · Page 8Linked to original sources
PubMed1982

Evaluation of myocardial metabolism, with N-13- and C-11-labeled amino acids and positron computed tomography.

To evaluate the utility of labeled L-amino acids (AA) for imaging regional myocardial AA metabolism by positron computed tomography (PCT), the myocardial uptake and clearance of Ala,* Glu, Gln, Asp, Leu tagged with N-13, and of C-11-tagged Asp, and oxaloacetate (Oxal), were examined in 44 experiments at control, during ischemia, and after transaminase inhibition. The myocardial time-activity curves recorded after intracoronary tracer injection had two clearance phases (an early and a late) for all N-13 AA, and three (early, intermediate, late) for the two C-11 compounds, with significantly different clearance half-times of 18.7 +/- 8.0 (s.d.) sec for the early phase, 141.7 +/- 56.5 sec for the intermediate, and 61.2 +/- 43.5 min for the late phase. The residual fractions ranged from 0.07 to 0.23 in normal myocardium, and consistently increased with ischemia by 0.01-0.07 for N-13-labeled Ala, Glu, Asp, and Leu, but not for N-13 Gln and C-11 compounds. Transaminase inhibition shortened the half-times of the late phases of N-13-labeled Ala, Glu, Asp, and Leu; had no effect on t1/2 of N-13 Gln and C-11 Oxal; and resulted in a loss of C-11 CO2 production and of the intermediate phase for C-11 Asp. On the PCT images, N-13 activity from labeled Ala and Glu was not decreased in an ischemic segment despite a significant flow reduction, as demonstrated by N-13 NH3 imaging and labeled microspheres. From the results, a three-compartment tracer kinetic model is proposed for the noninvasive quantification of Krebscycle activity, protein synthesis, and metabolic derangements related to ischemia.

Amino Acids↗
PubMed1981

13N-labeled L-amino acids for in vivo assessment of local myocardial metabolism.

The hot cell synthesis of sterile, pyrogen-free 13N-labeled L-amino acids was accomplished by employing the appropriate immobilized enzymes on a CNBr-activated Sepharose support and using remote, semiautomated systems. The syntheses were completed 6-12 min after cyclotron production of [13N]ammonia. Myocardial time-activity curves after intracoronary injection of 13N-labeled L-amino acids in dogs were triexponential in both normal and ischemic myocardium. Higher retention of 13N activity was observed in ischemic segments. Positron computed tomography imaging also showed increased uptake of 13N-labeled L-glutamate and L-alanine in ischemic segments compared with normal myocardium when blood flow corrections were made. Myocardial transaminases are primarily responsible for the observed retention fractions. It suggests the participation of the carbon skeletons of these amino acids in the Krebs cycle.

Amino Acids↗
PubMed1981

Effect of oral propranolol on rest, exercise and postexercise left ventricular performance in normal subjects and patients with coronary artery disease.

The effect of beta-adrenergic blockade with oral propranolol on resting, exercise and postexercise ventricular performance was evaluated using multiple-gated equilibrium cardiac blood and pool images in normal volunteers and patients with coronary artery disease. Propranolol produced no detectable effect on basal left ventricular function in normal subjects at doses producing intermediate (160 mg propranolol/day) and maximal (434 +/- 99 mg propranolol/day) beta blockade and in patients with coronary artery disease at clinically effective antianginal doses (162 +/- 47 mg propranolol/day). During exercise, a dose-related, negative inotropic effect was observed in normal subjects: 160 mg propranolol/day produced a small but statistically insignificant decline in exercise left ventricular performance, whereas maximal beta blockade significantly depressed the left ventricular response to exercise. In patients with coronary artery disease, propranolol's effect on exercise ventricular performance depended on the presence or absence of ischemic dysfunction during exercise. In patients with an ischemic functional response to exercise, propranolol significantly improved regional and global performance during and after exercise; in coronary artery disease patients with a normal response to exercise, propranolol had no significant effect on exercise and postexercise ventricular function. These results imply increased sensitivity to the effects of beta blockade in ischemic myocardium. In coronary artery disease patients with an abnormal response to exercise and in normal volunteers during beta blockade, propranolol's effect on exercise left ventricular performance was independent of changes in ventricular preload and after load related to heart rate and blood pressure.

Administration, Oral↗
PubMed1980

Emission tomography of the heart.

The utility and ultimate role of positron emission computed tomography in health care delivery is difficult to assess at present and needs to be defined in the future. It would seem that with improvements in instrumentation and physiologic indicators, and with the development of compact, reliable, and generator-like cyclotrons, "physiologic tomography" will become more widely applicable. Physiologic tomography of the heart undoubtedly represents an important new tool for investigative studies that will improve our understanding of cardiac physiology in health and disease. The quantiative aspects as well as simultaneous evaluation of more than one segment of myocardial performance, e.g., simultaneous study of mechanical function, blood flow, and metabolism and their interdependency, will provide new insights into myocardial physiology. Because many of the cardiovascular disorders may originate at the cellular or metabolic level, it is hoped that this technique will serve as a means for the early detection of cardiac disease, perhaps at a stage when it is still amenable to therapy.

Animals↗
PubMed1977

[Fistula carcinoma arising from chronic osteomyelitis (author's transl)].

224 cases of fistula carcinoma arising from chronic osteomyelitis from literature and 6 own observations are reviewed. This malignancy results in about 1,5% cases of chronic osteomyelitis. The mean age of all patients was 55.7 years. The sex relation male to female was 7.4:1. The time from the beginning of the chronic osteomyelitis up to the diagnosis of the fistula carcinoma was 33.6 years. This time is called "Exposition time". The analysis of this time shows that, the older the patient was at the beginning of the chronic osteomyelitis the shorter was the exposition time.

Adult↗
PubMedDate not supplied

Comparative study on the clinical use of protein S-100B and MIA (melanoma inhibitory activity) in melanoma patients.

BACKGROUND: The guidelines for the care of melanoma patients have not recommended the routine use of tumor markers up till now. In comparison to the blood parameters, two serum proteins have demonstrated their usefulness in the follow-up of melanoma patients: protein S-100B, a member of the S100 protein family, and "Melanoma-inhibitory activity" (MIA), a recently described 11 kd soluble protein. We analysed the serum levels of S-100B and MIA in non-melanoma control patients and in melanoma patients in different stages of disease (stage I-IV) to report on the sensitivity and specificity of both tumor markers. PATIENTS AND METHODS: The serum concentration of S-100B was evaluated by a luminoimmunometric assay (LIA) in 670 blood samples of 87 melanoma patients and, as controls, in 169 blood samples of patients with different skin diseases apart from melanoma. MIA serum levels were measured by an enzyme-linked immunoassay (ELISA) in 791 serial blood samples of 87 melanoma patients and in 158 blood samples of control patients. A cut-off of 0.12 microgram/l (S-100B) and 6.5 micrograms/l (MIA) served as upper normal values in the melanoma group as recommended by the producing industrial companies. In the control patient group, we additionally used the cut-off value of 0.2 microgram/l for S-100B and 8.5 micrograms/l for MIA, respectively. RESULTS: In stage I/II 37.5%, in stage III 50% and in stage IV 80% of the blood samples were S-100B positive (> or = 0.12 microgram/l) prior to treatment. Post treatment (after complete surgery) S-100B was below the cut-off value in stage I/II 83.9%, in stage III 82% and in stage IV 85.7%, respectively. For MIA we found in stage I/II 0%, stage III 53.8% and in stage IV 68.3% of the blood samples positive (> or = 6.5 micrograms/l) prior to treatment. Post treatment: stage I/II 88.3%, stage III 90.3% and stage IV 93.1% were below the cut-off value. In the control group we found 85.8% and 89.9% of the blood samples beneath the cut-off values for S-100B and MIA, respectively. CONCLUSION: We were able to identify the majority of patients with advanced metastatic melanoma by analysing the serum levels of S-100B and MIA. The specificity of both tumor markers was within acceptable limits. However, the available data suggest that a slightly higher cut-off value might be of clinical value.

Antigens, Tumor-Associated, Carbohydrate↗