Clinical experience with the soybean protein diet in the treatment of hypercholesterolemia.

The efficacy of the total substitution of animal proteins with a textured soybean protein in hypercholesterolemic individuals was assayed in 42 in-patients and 18 out-patients. The in-patients studied followed one of three different crossover protocols: in protocol A, the soybean diet was compared with a standard low lipid diet; protocol B compared two soybean diets, one with added cholesterol, one without; and protocol C compared a soybean diet containing a high P/S fatty acid ratio to one with a low P/S ratio. In all three protocols, the soybean regimen provided valid and reproducible hypocholesterolemic effects that were not modified by the addition of cholesterol. P/S variations appeared, however, to modify the final effect: soybean definitely had a decreased effectiveness with a low P/S (0.1) regimen. The overall plasma cholesterol changes in the 42 in-patients after 3 weeks on the different soybean diet protocols was -20%. Patients with type IIA and IIB hypercholesterolemia provided almost equivalent results, whereas patients with mixed phenotypes (IIB-III) appeared somewhat more sensitive to the dietary effect. Cholesterol decreased mostly in the low density lipoprotein fraction, but some very low density lipoprotein changes were also noted upon variation of the P/S ratio. The out-patients studied provided less satisfactory results. possibly due to the difficulty of adequately complying with the diet. These studies indicate that treatment with the soybean diet is an effective regimen for inducing a significant cholesterol reduction in type II patients refractory to standard low lipid regimens.

Fecal cholesterol excretion studies in type II hypercholesterolemic patients treated with the soybean protein diet.

The fecal steroid elimination profile was studied in 7 type II hyperlipoproteinemic patients given a low-lipid diet with textured soybean proteins, in order to define the mechanism of the hypocholesterolemic activity of this new dietary regimen. Four of the patients followed a 3- + 3-week cross-over protocol, comparing the soybean diet with a reference low-lipid diet with animal proteins. In these, fecal neutral steroids and bile acids were analyzed by chromatography during the two dietary periods. In spite of the clear hypocholesterolemic effect, no significant differences in steroid output were noted between the two dietary periods. In the 3 remaining patients, a chromatographic + isotopic method (by injecting 14C-labelled cholesterol i.v. 4-6 weeks prior to the dietary study) was employed. Again, no marked changes were noted in the fecal neutral steroid and bile acid outputs and the slope of the decay curve of the plasma cholesterol-specific activity was not changed by the experimental diet, in spite of the remarkable decrease in plasma cholesterol. The reported results do not provide a definitive contribution to the mode of action of the soybean protein diet. They suggest, however, that it is not an effect mediated by undigestible dietary components. The possibility of a cholesterol redistribution from plasma to tissue pools should be considered.

Bioavailability of digoxin in a new soluble pharmaceutical formulation in capsules.

The in vitro dissolution and the bioavailability of two pharmaceutical formulations of digoxin were compared, one being a common commercial tablet form and the other a solution of the glycoside in soft gelatin capsules. Digoxin capsules dissolved more readily in vitro and showed higher bioavailability than digoxin tablets in both dogs and humans. In dogs, the capsules and tablets were compared with an elixir of digoxin, which possesses complete bioavailability. The better bioavailability of digoxin capsules as compared with tablets may be explained by the fact that this formulation contains the cardiac glycoside in a solution.

Can pulmonary artery pressure be predicted without right heart catheterization in chronic obstructive lung disease?

We have investigated the dependance of observed pulmonary artery mean pressure (PAP) on body surface, age, PaO2, pH, PaCO2, hematocrit, and spirometric data (VC, FEV1/VC, RV/TLC) in 70 patients with chronic obstructive lung disease (COLD). After elimination of all variables that failed to correlate with PAP, multifactorial analysis showed that only two of nine independent variables, namely PaO2 and body surface, correlated significantly with PAP. According to our calculations, 28.9% of total PAP is predictable by PaO2, 1.5% by H+ concentration, 2.8% by RV/TLC, and 2.5% by body surface. Fully 64.2% of total variability was not accounted for by our regression analysis; thus the error of predicted PAP was so great (+/- 17 mm Hg for P = 0.05) as to invalidate the method. We also recalculated our subjects' PAP values by applying Enson's and Grassi's equations to our own lung function and biochemical data, and compared the predicted PAP values thus obtained with those measured directly in our subjects. Both equations proved imprecise and/or inaccurate in the individual case. From this we conclude that whereas available equations may be suitable for predicting the mean PAP value of a large population sample, the same equations cannot give a reliable prediction in individual cases.

Relationship between chronic PaCO2 and total body buffering capacity in patients with chronic obstructive lung disease.

17 subjects were carefully selected among 150 patients with COLD: all patients with one or more conditions or diseases that could alter the physiological response to chronic hypercapnia were eliminated. During a period of 13 to 28 days, the acid-base response to slow carbon dioxide changes was studied in the selected patients. Total body buffering capacity was expressed as dH+a/dPaCO2 and showed to be an inverse function of chronic PaCO2 (defined as the value of PaCO2 in clinical and acid-base steady status for each patient), according to the previous suggestions of Weiss and Dulfano and to the report of Ingram and co-workers during acute carbon dioxide changes in the same patients.

[The pulmonary artery hypertension in patients with sarcoidosis (author's transl)]. / L'ipertensione arteriosa polmonaire nella sarcoidosi.

Svanborg (1961) found normal pulmonary artery mean pressures in eleven patients with stage II sarcoidosis. By contrast Gluskowski et al. (1978) have shown few abnormally high values in the same condition. We have not found published haemodynamic data concerning stage O sarcoidosis. Thus we have performed right haemodynamic study (by Swan-Ganz catheters) on 19 patients with hystologically proven sarcoidosis (8 stage III, 6 stage II, 3 stage I and 2 stage 0). 13 of them underwent also haemodynamic study during exercise (1watt/Kg). Pulmonary artery hypertension (at rest or after exercise) was frequently found in stage III, and less frequently in stage II. In stage I pulmonary artery mean pressure was between 15 and 20 mmHg in three patients (out of three). In one case (out of two) in stage 0 (admitted to hospital owing to exertional dyspnoea) right heart catheterisation showed pulmonary hypertension during exercise in spite of normal pulmonary function tests (including spirometry, DLCO, pulmonary scintigrafic and X-ray pattern also using 3X magnification radiology).

Pharmacological control of platelet-vessel wall interactions in patients with chronic obstructive airway disease.

In the last few years great interest has been devoted to the role of platelet activation in the haemodynamic and thrombotic complications which frequently occur in patients with chronic obstructive airway disease. Several recent studies have shown, in fact, a number of alterations of platelet function in this pathological condition, such as an increased betathromboglobulin level and higher levels of malondialdehyde after collagen and thrombin platelet stimulation compared to age and sex matched control subjects. Our study indicates that the platelet regeneration time is shortened in patients with chronic obstructive airway disease in respect to that of controls (p less than 0.001). The administration of dipyridamole (425 mg/die) resulted in a significant prolongation of the platelet regeneration time in these patients indicating that the drug was effective in reducing the increased platelet turnover.

Regional lung perfusion and pulmonary artery pressure in chronic obstructive lung disease.

In 22 chronic bronchitics with or without emphysema, the authors measured regional pulmonary perfusion in the supine position and calculated the ratios of radio-active tracer (131I-MAA) concentrations in the lung apices and bases (U/L ratio). This ratio was found to be normal in the right lung and tendentially high (though not to a statistically significant degree) in the left lung, this being probably due to the presence of an enlarged heart (13 patients showed evidence of right ventricle hypertrophy and/or overload). The correlation between the U/L ratio and functional impairment of respiration expressed spirometrically failed to reach statistical significance and the same was true of the correlation between the U/L ratio and mean pulmonary arterial pressure at rest.

Soybean-protein diet in the treatment of type-II hyperlipoproteinaemia.

A soybean textured protein induced a 14% decrease of plasma-cholesterol levels after two weeks and 21% after three when substituted for animal proteins in a group of 20 patients with type-II hyperlipoproteinaemia. Comparison of soybean diet with a standard low-lipid diet in the same patients, according to a cross-over protocol, indicated that this hypocholesterolaemic effect was not due to differences in the lipid composition of the two diets. The hypothesis that a soy protein has a hypocholesterolaemic action per se is supported by the results of a subsequent experiment in 8 type-II patients in whom the addition of cholesterol (500 mg/day) to soy protein did not modify the hypocholesterolaemic response.