Abnormal myocardial texture demonstrated by ultrasound in two patients with idiopathic haemochromatosis

We studied by cross-sectional echocardiography seven patientsaffected by idiopathic haemochromatosis without clinical signsof heart failure. In two patients the heart muscle showed apeculiar echocardiographic texture at the level of the endocardium.No differences were noticed in clinical and haematological findingsof the patients with and without abnormal texture. Increasedechogenicity of the subendocardial myocardium should be lookedfor in patients with idiopathic haemochromatosis.     

Oral Rehydration Therapy in Malnourished Infants with Infectious Diarrhoea

ABSTRACT. The clinical response and changes in water and salt homeostasis was studied for 36 hours during oral rehydration therapy with a rehydration solution containing 60 mmol sodium/1 (ORSffl) in 14 malnourished 3- to 15-month-oId Turkish infants with acute infectious diarrhoea. All patients were successfully rehydrated with this treatment. Sodium was efficiently absorbed from the gut and water balance was rapidly restored. Because of excess fluid retention following the initial rehydration period about 50% of the patients became oedematous. Urine volume and urinary sodium excretion were found to be much lower than in well-nourished patients of the same age with acute diarrhoea who were treated in the same way. In all of the malnourished infants the serum sodium level remained within the normal range during treatment. The results show that malnourished infants retain much more fluid and sodium than infants who are in a normal nutritional state. Excessive retention of water and salt seem to be due to an inability of the kidneys to control sodium and fluid homeostasis while orally administered sodium and fluid are being absorbed from the gut. The results show that ORT is safe and efficient in the treatment of malnourished infants with acute diarrhoea. But since these infants run a high risk of developing a severe retention of fluid and salt, and consequently may develop circulatory failure due to hypervolemia during oral rehydration therapy, it is important to carefully monitor the volume of fluid that is given.     

Role of presynaptic purinoceptors and cyclic AMP on the noradrenaline release in cat cerebral arteries

Field electrical stimulation (ES), K+ (50 mM) or ionophore X-537A (0.01 mM) induced tritium release from cat cerebral arteries preincubated with [3H]noradrenaline (NA). Adenosine and AMP (0.5 mM) did not modify tritium release caused by ionophore X-537A, but these agents and ATP (0.5 mM) significantly reduced that elicited by ES and K+; this reduction was antagonized by 1-methyl-3-isobutylxanthine (MIX; 0.05 mM). Inosine (0.5 mM) and the agonist of purinergic A2-receptors, 5'N-ethyl-carboxamide adenosine (NECA; 0.5 mM) had no effect, but the agonist of purinergic A2-receptors L-N6-phenylisopropyl adenosine (L-PIA; 0.1 mM) diminished tritium efflux caused by ES and K+. The adenosine inhibition of ES-induced radioactivity release was not affected by indomethacin (0.05 mM). MIX (0.05 mM) increased tritium release evoked by ES and K+. Agents that increase intracellular cyclic (c)AMP levels, such as dibutyryl cAMP (0.5 mM), the phosphodiesterase inhibitor Ro 20-1724 (0.1 mM), and the activators of adenylate cyclase, forskolin (0.005 mM) and NaF (2 mM) reduced tritium secretion elicited by ES and K+. However, the intracellular increase of cyclic GMP (cGMP) caused by 8-Br-cGMP did not affect this secretion. Dipyridamole (0.05 mM) and the adenosine deaminase inhibitor erythro-9-2-hydroxy-3 nonyl adenosine (EHNA; 0.1 mM) also produced inhibition of tritium secretion elicited by ES and K+. Dipyridamole reduced both the uptake of [3H]NA and [3H]adenosine.(ABSTRACT TRUNCATED AT 250 WORDS)     

PRESERVATION OF THE PULMONARY VASOCONSTRICTOR RESPONSE TO ALVEOLAR HYPOXIA DURING THEADMINISTRATION OF HALOTHANE TO DOGS

The action of halothane on the pulmonary vasoconstrictor responseto unilateral alveolar hypoxia was studied in two groups ofdogs. In the first group the redistribution of blood flow betweenthe two lungs was studied with a radioactive isotope method,which provided intermittent measurements, whilst in the secondgroup the distribution of blood flow was observed continuously.In both groups there was no significant alteration of the hypoxicvasoconstrictor response with inspired halothane concentrationsvarying from 0.5 to 1.5%.     

Influence of calcium on noradrenaline release evoked by 5-hydroxytryptamine,tyramine and potassium from goat pial arteries

The release of tritium (³ H) evoked by tyramine, potassium (K⁺) and 5-hydroxytryptamine (5-HT) from goat pial arteries preloaded with [³ H]noradrenaline (³ H-NA) was studied. In normal Krebs-bicarbonate solution (KBS) all these agents caused a transient increase in radioactivity release over the basal spontaneous outflow. The pattern of release evoked by 5-HT was similar to that induced by tyramine with a slow onset and decline, but different from that induced by K⁺ which produced a rapid peak of ³ H release followed by a quick fall. The removal of Ca²⁺ from the medium did not modify the efflux of radioactivity caused by tyramine, but the ³ H efflux produced by K⁺ was markedly reduced. Nevertheless, in this Ca²⁺ -free medium the ³ H release evoked by 5-HT was partially, but significantly, decreased. These results indicate that K⁺ evokes NA release by a Ca²⁺ -dependent process, probably of an exocytotic nature, while tyramine mediates NA release by means of a Ca²⁺ -independent mechanism. However, 5-HT possesses a Ca²⁺ -dependent and a tyramine-like component.     

Balloon Angioplasty and Endoluminal Stenting of Clinically Significant Human Carotid Artery Occlusive Lesions: A New Model for Ex Vivo Morphological Analysis

The successful use of balloon angioplasty and intravascular stenting for the treatment of atherosclerotic lesions in the coronary and peripheral arteries has recently led to the application of these techniques to the management of carotid artery stenosis. We have, therefore, attempted to determine the local consequences of these interventions in the carotid circulation by developing an ex vivo model of simultaneous balloon angioplasty and endoluminal stenting of clinically significant human internal carotid artery occlusive lesions. The following report describes this model and discusses the related clinical issues.