Comparative beta-adrenoceptor blocking effects of propranolol, bisoprolol, atenolol, acebutolol and diacetolol on the human isolated bronchus.

Five beta-adrenoceptor blockers, propranolol, acebutolol, diacebutolol, atenolol and bisoprolol, were tested for their antagonistic effect against isoprenaline on human isolated bronchi. The results showed (1) that only propranolol exerted a competitive antagonistic effect against isoprenaline (pA2 = 9.40 +/- 0.22, n = 7) whereas the other drugs did not, and (2) that, in the presence of beta-adrenoceptor blockers in the plasma concentrations reported after a single usual therapeutic dose, the doses of isoprenaline giving the same bronchodilator effect must be multiplied by 32.6, 5.51, 4.63, 2.82 and 1.95 respectively with propranolol, diacetolol, acebutolol, atenolol, and bisoprolol. It was concluded that (1) atenolol and bisoprolol were the least potent drugs at bronchial level in therapeutic plasma concentrations and (2) that tests performed on the human isolated bronchus might be a useful screening procedure for new drugs with potential activity on the airways.

Variations in lipoproteins, hormones and blood glucose during the early acute phase of myocardial infarction.

This study reports on 22 patients (18 men, 4 women), 45-83-year-old admitted to hospital less than 24 h after the first clinical signs of myocardial infarction. Lipids, lipoproteins, serum insulin and growth hormone, urinary cortisol and vanillylmandelic acid and blood glucose were analysed on the day of admission (day 1) and on days 2, 4 and 8 of the acute phase. Results for lipoproteins generally confirm those of earlier studies: lowered total cholesterol (day 1-8), LDL-cholesterol (day 1-2), HDL-cholesterol (day 2-8), LDL apo B (day 1-2) and apo A-1 (day 1-8). There was no significant correlation between stress hormone and plasma lipoprotein alterations. Blood glucose decreased progressively (P less than 0.05) between day 1 and day 8. Glucose value at day 1 correlated significantly with nonesterified fatty acids, total cholesterol and LDL constituents, but not with HDL-cholesterol and apo A-1. Metabolic disturbances modifying blood glucose thus might be involved in LDL changes, whereas other processes govern HDL changes.

Red blood cell aggregation in preterm and term neonates and adults.

Aggregation of red blood cells (RBC) is a major determinant of blood viscosity and of blood circulation through vessels with slow flow (i.e. veins). RBC aggregation and plasma fibrinogen were studied in placental blood samples from 25 neonates with 24 to 41 wk of gestation and in blood from 13 normal adults. The rate and final extent of RBC aggregation were measured by means of a rheoscope (increase in light transmission during blood stasis). Both the rate and extent of RBC aggregation were low in the premature infants, increased with gestational age, and reached the highest values in the adults. Blood from seven infants with 24 to 28 wk of gestation did not show any significant RBC aggregation during the first minute of stasis. RBC aggregation was closely related to the fibrinogen level. Cross-suspension studies (neonatal RBC in adult plasma and adult RBC in neonatal plasma) showed that neonatal and adult RBC had the same aggregation pattern when they were suspended in the same plasma. Moreover, neonatal and adult RBC demonstrated the same strong aggregation when they were resuspended in 1% dextran. These results indicate that specific plasma properties are responsible for the decreased RBC aggregation observed in the neonates while their specific RBC properties do not affect RBC aggregation.

[Blood and plasma hyperviscosity in primary hyperlipidemia]. / Hyperviscosité sanguine et plasmatique au cours des hyperlipidémies primitives.

Plasma and blood viscosities were studied in 15 hyperlipidemic (HLP) patients and in 10 healthy volunteers. Viscosities were measured at 25 degrees C using a couette type viscosimeter. Plasma and blood viscosities were significantly increased in HLP patients. This increase in viscosity was better correlated with triglyceride than with cholesterol level. This result might partially account for the clinical differences observed between hypertriglyceridemia and hypercholesterolemia.

Erythrocyte aggregation during normal pregnancy.

Red blood cell aggregation induced by fibrinogen is a major determinant of the non-Newtonian flow behavior of blood and has been suggested as a possible contributing factor for thrombogenesis. Given the elevated fibrinogen levels and the incidence of thrombotic accidents in pregnancy, a study was designed to assess red blood cell aggregation at selected gestational periods. Three separate in vitro aggregation assays were used: (1) aggregation half time, (2) zeta sedimentation ratio, and (3) microscopic aggregation index. Our results indicate that red blood cell aggregation is increased throughout normal pregnancy (i.e., at 10, 25, and 36 weeks and during labor) in comparison to that in nonpregnant women. Significant correlations between plasma fibrinogen concentration and zeta sedimentation ratio (p less than 0.001) or aggregation half time (p less than 0.02) were demonstrated, but the correlation coefficient for the microscopic aggregation index technique did not reach significance (p greater than 0.20). Type O-positive red blood cells suspended in plasma from pregnant women also exhibited increased aggregation (p less then 0.001), thus suggesting plasma rather than cellular factors for the enhanced aggregation. Possible influences of abnormal fibrinogen structure during pregnancy are considered and the implications of increased red blood cell aggregation vis-à-vis altered blood viscosity are discussed.

Red blood cell aggregation in nephrotic syndrome.

Red blood cell (RBC) aggregation induced by fibrinogen is a major determinant of the non-Newtonian flow behavior of human blood and has been suggested as a possible contributing factor for thrombogenesis. Given the elevated fibrinogen levels and the high incidence of thrombotic accidents in nephrotic syndrome (NS), a study was designed to assess RBC aggregation in this disease. Three different aggregation assays were used: (1) changes in light transmission through static cell suspensions, aggregation half time (AHT); (2) low gravity centrifugation of blood in nearly vertical tubes, zeta sedimentation ratio (ZSR); (3) direct observation of dilute RBC suspensions, microscopic aggregation index (MAI). The results indicate that RBC aggregation, as measured by AHT and ZSR, is increased significantly in NS patients versus healthy controls (P less than 0.001 for both methods); this increase was not a function of renal insufficiency. The AHT and ZSR data were well correlated with plasma fibrinogen levels (r = 0.75 and 0.84, respectively). No differences were observed with the MAI method, since with this technique the aggregation process reaches an asymptotic plateau for the range of fibrinogen found in NS. Implications of increased RBC aggregation and thus increased blood viscosity and flow disturbances on thrombogenesis are discussed.

[Venous thromboembolic accidents during idiopathic hyperlipaemia]. / Les accidents thrombo-emboliques veineux au cours des hyperlipidémies idiopathiques.

The authors report 30 cases of venous thromboembolic accidents during familial hyperlipaemia. This type of accident, never previously described, calls for the following comments: (1) there was a striking number of recurrences in some patients although none of the usual contributing factors of thromboembolic disease were present; (2) the accidents only occurred in patients with endogenous hypertriglyceridemia (mixed type IIb hyperlipaemia, type IV endogenous hypertriglyceridaemia); (3) the accidents ceased completely after the metabolic disorder was corrected. In the prevention of post-operative thromboembolic disease more attention than before should be paid to patients with endogenous triglyceridaemia.

[Pituitary and hypothalamic metastases : 5 cases (author's transl)]. / Métastases hypophysaires et hypothalamiques. Etude anatomo-clinique de cinq observations.

Five cases of metastatic cancer in the pituitary gland are reported, four of which were revealed by chiasmatic syndrome and one by diabetes insipidus. Transphenoidal surgical treatment was possible in three cases. This site of metastasis is considered exceptional because of its customary inactivity. It is probable that the metastasis most often remain unrecognized and so, it requires careful study of the slightest sign because of treatment possibilities.

Does the corticoadrenal adenoma with "pre-Cushing's syndrome" exist?

An adrenal tumor was discovered fortuitously in a patient with no clinical features of Cushing's syndrome. On adrenal imaging, there was good uptake in the nodule but no visualization of the contralateral adrenal. The latter was seen, however, in a second scan performed under ACTH treatment. In the hormone assessment, basal cortisol and 17-hydroxycorticoids were normal and cortisol diurnal variation was near normal, but a dexamethasone suppression test and ACTH responses to metyrapone and insulin hypoglycemia were abnormal. Eight months after excision of a spongiocytic-type adenoma, the remaining adrenal was visible on scintigram and the hormonal tests were normal. This pattern suggests that the clinical Cushing's syndrome but enough to suppress partially ACTH and, consequently, visualization of the contralateral gland.

[Waldenström's disease and periarteritis nodosa: fortuitous association? (author's transl)]. / Maladie de Waldenström et péri-artérite noueuse: association fortuite?

A 48-year-old-woman had simultaneously a peri-arteritis nodosa (PAN) and a Waldenström disease. PAN's symptoms were quickly regressive, neuropathy excepted (with slowness) under treatment by cyclophosphamide and prednisone. Hemopathy is now stabilized. Such a pathological association is exceptional (2 other cases in literature). Is it accidental? No cryoglobulinaemia or circulating immune-complexes or HBS antigen were found. Immunofluorescence study of arteriolar lesions in muscle showed a polyclonal fixation in inflammatory granuloma and monoclonal (IgM lambda) on endothelial side. Passive deposit is not excluded, because research of specific activity of IgM lambda (against fibrin or endothelial cells) was negative. Waldenström's disease has probably facilitated apparition of necrotizing angeitis but mechanism is not proved.

[Polychimiotherapy and Waldenström's macroglobulinemia (author's transl)]. / Polychimiothérapie et macroglobulinémie de Wadenström.

A 63-year-old man, with a Waldenström's disease discovered by cryoglobulinemia (ischemic lesions of fingers) was quickly aggravating (hyperviscosity syndrome) under treatment by chlorambucil in a dosage of 8 mg daily. We obtained a dramatic remission with combination of cyclophosphamide, vincristine, adriamycin and prednisone surrounding a total body irradiation. A new trial of polychimiotherapy (with lower dosage) for severe Waldenström's disease is actually on study.