[Heart valve involvement in systemic lupus erythematosus: an echocardiographic study].

The purpose of this study was to evaluate the spectrum of morphologic and functional cardiac involvement in a selected population of patients with systemic lupus erythematosus (SLE) by means of echocardiography. Thirteen patients (2 male and 11 female) affected by SLE, mean age 41.9 years (range, 21-64), underwent M-Mode, two-dimensional and Doppler echocardiography.

Increased hydrogen peroxide formation in platelets of patients affected with essential thrombocythaemia (ET).

The basal platelet level of reactive oxygen species and their enhancement following stimulation by different agonists were determined in a selected group of patients with essential thrombocythaemia (ET). Activated platelets had lower levels of superoxide anion and higher intracellular concentrations of hydrogen peroxide than controls. Higher levels of lipid peroxidation induced by N-ethylmaleimide were also observed.

Generation of hydrogen peroxide in resting and activated platelets.

The production of hydrogen peroxide was measured by following the oxidation of dichlorofluorescein (DCFH) entrapped into platelets. Resting platelets produced nanomolar quantities of DCF, which was proportional to the concentration of platelets and was steady during 1 h of incubation. A significant increase of basal DCF fluorescence was induced by stimuli namely thrombin, arachidonic acid, the Ca2+ ionophore A23187 and PMA.

Treatment of proteoglycan aggregates with physeal enzymes reduces their ability to inhibit hydroxyapatite proliferation in a gelatin gel.

In vitro, cartilage proteoglycans (PGs) are effective inhibitors of hydroxyapatite formation and growth. Their inhibitory ability decreases with decreasing PG size and charge density. It has been suggested that the enzyme-mediated alteration in the size and conformation of PGs in the growth plate may similarly facilitate the calcification process.

The concept of pain in the 17th century.

The 17th century is very important in the history of sensation and pain. Philosophers, as Descartes, Hobbes, Spinoza, defined a new philosophy of science. Physicians of the iatro-chemical school introduced the first principles of biochemistry, tied to the sensations.

1,5-Benzodiazepines. X. Dialkylamino substituted 1,5-benzodiazepine and [1,2,4]triazolo [4,3-a][1,5] benzodiazepine derivatives with inhibitory activity on PAF-induced platelet aggregation.

Novel 4-(dialkylamino) substituted (4, 5 c, 8) and 2,4-bis(dialkylamino) substituted (6) 1,5-benzodiazepine derivatives were synthesized. Both these new compounds and the substituted 4H-[1,2,4]triazolo[4,3-a][1,5]benzodiazepine-5-amines 2 a-h, recently described by us, were tested in vitro for their inhibitory activity on the PAF-induced aggregation of human platelets. Actually, bicyclic compounds 4 d, 5 c and tricyclic compounds 2 g, h showed a significant activity: in all them the dialkylamino substituent was the 4-(ethoxycarbonyl)-1-piperazinyl group.

Hydroxyapatite formation in the presence of proteoglycans of reduced sulfate content: studies in the brachymorphic mouse.

Proteoglycans from the brachymorphic (bm/bm) mouse have a reduced sulfate content due to the impaired activity of adenosine phosphosulfate phosphokinase in these animals. X-ray diffraction and infrared analyses of the mineral from the calcified cartilage of the bm/bm mice demonstrate the presence of significantly larger and more perfect hydroxyapatite crystals of lower carbonate to phosphate content than crystals found in the control animals. No differences were seen in the mineral content, crystallite size, CO3:PO4 ratio, or infrared splitting factors measured in the diaphyseal bone from these animals.

Oxidative metabolism of human platelets.

The reducing capacity toward cytochrome c present in human resting platelets increases upon platelet stimulation, and is partially inhibited by superoxide dismutase. This activity therefore represents the generation of superoxide anion. In order to evaluate hydrogen peroxide formation a quantitative assay by mean of dichlorofluorescin (DCFH) has been set up.

Central pruritus. Case report.

An 82-year-old woman experienced generalized pruritus not due to skin or systemic disease. Scratching the skin with a needle induced a crisis of intense pruritus, insensitive to any drug. The pruritus had the characteristics of a central sensation.

Mode of action of 2-(diethylamino)-7-ethoxychromone on human platelets.

The in vitro effect of 2-(diethylamino)-7-ethoxychromone (RC39XVIII) on human platelet aggregation induced by several agonists and on thromboxane B2 formation, granule release and intracellular cAMP elevation has been studied. The chromosome-derivative exerts a dose-dependent inhibitory effect on aggregation produced by U46619, arachidonic acid, thrombin, collagen and ADP. RC39XVIII inhibits aggregation, TxB2 formation and granule release in parallel.

Antiplatelet effect of 2-(diethylamino)-7-hydroxychromone.

In this study the in vitro influence of 2-(diethylamino)-7-hydroxychromone (RC39II) on platelet aggregating responses, thromboxane A2 (TxA2) production, release reaction and intraplatelet cyclic AMP (cAMP) content has been investigated. The drug exerts a dose-dependent inhibitory effect on aggregating response to arachidonic acid, U46619, thrombin, collagen and calcium ionophore A23187. Inhibiting concentrations of RC39II also prevent platelet release reaction and TxA2 formation.

Concentration-dependent effects of dentin phosphophoryn in the regulation of in vitro hydroxyapatite formation and growth.

The effect of dentin phosphophoryn on hydroxyapatite formation and growth was studied in an in vitro gelatin gel diffusion system. Phosphophoryn, in low concentrations (0.010-1 microgram/ml) promoted de novo hydroxyapatite formation; at a higher concentration (100 micrograms/ml) in the same system, the dentin matrix protein inhibited hydroxyapatite growth.

[Mass transfer of magnesium in hemodialysis].

The rate of mass-transfer (MT) of magnesium during hemodialysis was studied in thirty-five patients with hypermagnesemia (Mg = 3.75 +/- 0.72 mg/dl) undergoing chronic hemodialysis.

[Plasma levels of atrial natriuretic peptide and its relationship with arterial blood pressure before and after peritoneal dialysate infusion].

The acute modifications of atrial natriuretic peptide (ANP) plasma levels due to intraperitoneal dialysate infusion and the relationship between ANP and arterial blood pressure were studied in 17 patients on continuous ambulatory peritoneal dialysis (CAPD). ANP plasma levels were 159.18 +/- 87.

Platelets of patients affected with essential thrombocythemia are abnormal in plasma membrane and adenine nucleotide content.

The adenine nucleotides present in distinct cellular compartments of platelets of 27 patients affected with essential thrombocythemia have been measured. In order to quantify granule-bound nucleotides and adenylic cytoplasmic pool, platelets have been stimulated with thrombin or treated with increasing digitonin concentrations, respectively. Among patients, we have identified two groups: 12 patients (Group 1) had normal platelet level of ATP and ADP both in dense granules as well as in cytoplasmic pool.

Lateralisation of pain in cluster headache.

In 27 patients with cluster headache a careful sensory examination of the entire body was performed. The exam included: the measurement of sensory thresholds with mechanical and electrical stimuli, the assessment of cutaneous and deep hyperalgesia and the ischaemic test of the upper limbs with limbs at rest. In most patients a lateralisation of the findings was observed: cutaneous and deep hyperalgesia were prevalent in the side of cluster headache attacks.

Protein composition in resting and activated platelets of type I diabetic patients.

Protein composition of platelets of eleven type I diabetic patients and thirteen control subjects were analyzed by SDS polyacrylamide gel electrophoresis. Bands have been scanned and quantified. No significant difference was shown between controls and patients in any of the bands identified in electrophoretic patterns of whole platelet, membrane fraction, resting, activated and aggregated cytoskeleton.

[Cardiac rhythm disorder in infection caused by cytomegalovirus in patients with kidney transplant].

A higher incidence of arrhythmias was observed in 16 renal allograft recipients infected with Cytomegalovirus (CMV), as compared to 26 patients who were transplanted during the same period and did not contract the infection (43.7% vs. 3.

Pain in mitral valve prolapse.

Thirty subjects with mitral valve prolapse were carefully observed, in order to investigate whether chest pain, characteristic of angina pectoris, was present. No cases of angina pectoris or of heart pain were observed. A characteristic which did emerge was that 86% of the subjects suffered a typical myofascial pain of the muscles of the chest.