Changes in neurotransmitter parameters in the brain induced by L-cysteine injections in the young rat.

A single subcutaneous injection of L-cysteine (1.2 mg/g body wt.) to 4-day-old rats leads to atrophy of the brains examined 27-31 days later. The brains could be separated into two groups (type 1 and 2) on account of the degree of atrophy. Type-1 lesion, with a brain weight reduction of 20%, was dominated by a severe reduction in high-affinity uptake of L-glutamate in CNS regions receiving corticofugal fibers such as thalamus and striatum. Glutamate decarboxylase was only reduced in cortical structures. In type-2 lesion, with a severe brain atrophy of about 50%, high-affinity glutamate uptake was further reduced and there was a more pronounced reduction in glutamate decarboxylase activity in several brain regions. Cholinergic neurons were less affected by the lesion and the levels of choline acetyltransferase showed a relative increase in brain regions which partly compensated for their reduction in size.

Congestive heart failure and ejection fraction in acute myocardial infarction.

Left ventricular ejection fraction (EF) was determined by means of radionuclide ventriculography (RNV) in 477 patients 8-12 days after an acute myocardial infarction (AMI). EF was correlated to infarct size and clinical and radiological parameters of congestive heart failure (CHF). The 138 patients (29%) who had signs of CHF had a mean (+/- SD) EF of 35 +/- 14% and a relative heart volume of 597 +/- 112 ml/m2 compared to 51 +/- 14% and 487 +/- 88 ml/m2 among those without CHF. The 52 patients who also had radiological signs of CHF had a mean EF of 27 +/- 12% versus 35 +/- 14% among those with clinical signs and symptoms of CHF. Presence of CHF was positively correlated to the size of AMI and to the reduction of EF. CHF was seen with increasing frequency from 16% in small to 46% in large first infarctions. Patients with reinfarctions showed the same correlation between these parameters, however, with subsequently more depressed EF values and more frequent presence of CHF due to previous myocardial damage. CHF was seldom (8%) observed in patients with EF greater than 50%. In contrast, 67% of the patients with EF less than 35% had CHF. Thus patients with an EF less than 35% represent a high risk group with regard to development of CHF and should be followed closely. It is suggested that radionuclide measurement of EF adds important clinical information in patients with diagnostic uncertainty of CHF.

Cardiac performance in hyperthyroidism assessed by systolic time intervals and radionuclide ventriculography.

Systolic time intervals (STI) and radionuclide ventriculography (RNV) were used in the assessment of cardiac performance in 22 patients with hyperthyroidism before and after antithyroid treatment. STI as well as RNV showed enhanced myocardial contractility which was normalized after antithyroid treatment. Beta-blocker treatment did not influence the hypercontractility in hyperthyroidism. This implies that beta-blockers alone cannot be regarded as satisfactory long-term treatment and that mechanisms other than increased sympathoadrenal drive are involved in the hypercontractility in hyperthyroidism. RNV suggested valvular regurgitation, probably of the mitral valve, in 11 patients. Possible hemodynamic consequences are discussed.

Regional distribution of perchloric acid soluble proteins during the development of rat brain.

The regional contents of perchloric acid (PCA)-soluble proteins were determined during the development of rat brain. The soluble proteins in cortex, mesencephalon and medulla oblongata decreased gradually to adult age, whereas the levels in cerebellum increased significantly 12 days after birth followed by a decline to adult age. The developmental changes in the soluble proteins in retina, which showed the highest content of these proteins, were different from that of the other regions. Changes in the staining intensities of the main protein bands following SDS-gel electrophoresis were observed during the development of all regions. The patterns of the soluble proteins from retina and cerebellum were less complex than those of the other brain regions and liver and resembled that of the chromosomal high-mobility group proteins and H 1 histones.

Combined scintigraphy of liver, spleen, and lung in the diagnosis of subphrenic abscess.

Two hundred and fifty-six patients have, during the past 5 years, been examined by combined liver, spleen, and lung radionuclide imaging. The reason for this investigation was to identify or rule out subphrenic abscess, which is a rare but feared complication of abdominal surgery. Primary subphrenic abscess may also be seen, and in such cases the diagnosis is extremely difficult. Subphrenic abscess was demonstrated by radionuclide imaging in 17 patients, and all of these were later confirmed by surgery. In this study there was one false-positive and one false-negative result. During this period other pathological conditions involving lung and liver and with symptoms similar to subphrenic abscess have also been demonstrated by this technique, such as lung embolism and liver abscess.