[Reduction of lipoproteins with apoAI but without apoAII (LpAI) in non-insulin-dependent diabetic patients]. / Réduction des lipoprotéines avec apoAI mais sans apoAII (LpAI) chez les diabétiques non insulino-dépendants.

Recent data suggest the existence of a relationship between ischemic heart diseases and apolipoprotein A-I containing lipoproteins. The latter and other classic lipid-lipo-protein-apoprotein parameters were quantified in 25 non-insulin-dependent diabetics and 26 normoglycemic normolipidemic subjects. Compared to a control group, non-insulin-dependent diabetics have higher levels of plasma cholesterol (p < 0.05), triacylglycerol, apolipoprotein B (p < 0.001). In contrast, their lipoprotein particles containing only apolipoprotein AI without apolipoprotein AII and apoAI/apoB ratio were lowered (p < 0.001). In our diabetics, apolipoprotein AI was found at normal level but its distribution between high density lipoproteins ('HDL') and 'non-HDL' was abnormal. Also, the distribution of particles containing apolipoprotein A-I without apolipoprotein A-II in non-insulin-dependent diabetics was found abnormal. A higher proportion of both apoAI and LpAI were found in the 'non-HDL' fraction. These data show that lipoprotein metabolism is affected in non-insulin-dependent diabete mellitus. The disease is associated to a lipoprotein profile which is in favour of the atherogenic process.

Theophylline pharmacokinetics and metabolism in rabbits following single and repeated administration of Capsicum fruit.

Pharmacokinetics and metabolism of theophylline were studied in three groups of male rabbits, after intravenous administration (12 mg/kg), with and without oral ground Capsicum fruit suspension. Compared with control values, plasma theophylline half-life of distribution and of elimination, areas under plasma curves, clearance and volume of distribution did not show any significant difference. On the contrary, the elimination rate constant (k1,0) is significantly different (0.01 < P < 0.05) after a single dose of capsicum and remained unchanged after a repeated dose. Concerning the metabolism of theophylline in rabbits, the results showed that the oral administration of a single dose of Capsicum fruit suspension does not significantly affect the urinary excretion of theophylline and its metabolites--1,3-dimethyluric acid (1,3-DMU) and 1-methyluric acid (1-MU). On the other hand, after a repeated dose of Capsicum fruit for 7 days, the quantity of 1-MU was significantly reduced (0.01 < P < 0.05). In conclusion, it was found that a single dose of Capsicum fruit could affect pharmacokinetic parameters of theophylline (k1,0), while a repeated dose affected the metabolic pathway of xanthine oxidase.

Effects of capsaicinoids on oxidative metabolism of caffeine in isolated rat hepatocytes.

The metabolism of caffeine was studied in isolated rat hepatocytes, in the absence and presence of capsaicinoids. Caffeine and four primary metabolite fractions were identified by high performance liquid chromatography: 1,7-dimethylxanthine, 3,7-dimethylxanthine, 1,3-dimethylxanthine and 1,3,7-trimethyluric acid. The incubation with the lowest concentrations (0.1 and 1 microM) of capsaicinoids (natural extract, capsaicin, dihydrocapsaicin) showed a stimulatory effect on caffeine metabolism, which was further enhanced with capsaicin. At 10 microM, capsaicin stimulated the two pathways of metabolism of caffeine (N-demethylation and C-8 oxidation). In contrast, dihydrocapsaicin and the natural extract seem to inhibit the N-demethylation pathways without affecting the C-8 oxidation route. The inhibitory activity on the N-demethylation pathways and especially the N-7 demethylation pathway was pronounced at the first 30 min of incubation. These results suggest that the two pathways (N-demethylation and C-8 oxidation) are mediated by different isozymes of cytochromes P-450. This is in agreement with recent findings.

[Absence of litholytic effects of zinc sulfate and copper sulfate in experimental lithiasis in rats]. / Absence d'effets litholytiques du sulfate de zinc et du sulfate de cuivre vis-à-vis de la lithiase expérimentale chez le rat.

Seventy two male Wistar-strain rats were fed lithogenic diet with ethylene-glycol within three weeks. At the end of this treatment, six rats were killed in order to determine the oxalate and calcium concentrations in renal tissue. Remained rats was randomly divided in four series, each series consisting of three groups. In first series (T), the animals were treated with distilled water; in the second (D1Zn), the animals were treated intramuscularly with the zinc at the rate of 24 micrograms per 100 grams of body weight and per day; in the third (D2Zn), 240 micrograms of zinc were administrated to animals and in the last series (D2Cu), the animals were treated at the same dose as the previous series, but with the copper. The groups which making up each series were killed successively at the 5th, 10th and 15th day after ending treatment with ethyleneglycol in order to determine urinary pH, percentage of water in renal tissue, uremia and concentrations of oxalate and calcium in renal tissue. Then, the comparisons of means were carried out, at each time, between different treated groups and reference group which was treated with distilled water. Litholytic effect was found in all series, including that which had been treated with distilled water. However, compared to reference animals, no acceleration of litholytic process was induced by zinc or copper. The high doses used in these experimentations proved therefore that calcium oxalate calculi were insoluble by zinc and copper.

Puzzling biochemical thyroid profile in patients with multinodular goitre originating from a mild iodine deficient area in Tunisia.

Thirty Tunisian patients with a voluminous multinodular goiter with cold nodules and inhabiting a region of mild iodine deficiency, have been studied. The 131 I fixation by the thyroid, three hours after ingestion was significatively higher than in normal population. Fourty six per cent of the patients have stable iodine urine contents less or equal to 0.39 mumol/L. Three serum concentrations were paradoxically abnormal: thyrotropin (TSH), thyroglobulin (TG) and gammaglobulin concentrations. Fourty seven per cent of the serum thyrotropin (TSH) levels were less than the normal values though the serum total triiodotyronine (TT3), tetraiodotyronine (TT4), free triiodotyronine (FT3), free tetraiodotyronine (FT4), antithyroglobulin antibodies, total protein, triglycerides and cholesterol concentrations were normal. Serum thyroglobulin (TG) rates were elevated, ranged from 2 to 10,180 ng/ml and twenty five per cent of our patients showed levels greater than 500 ng/ml. The gammaglobulin levels were greater than normal in sixty eight per cent of our patients though only 10% of our patients manifest antithyroglobulin antibodies.

[Does vitamin E protect against experimental lithiasis?]. / La vitamine E protège-t-elle contre la lithiase expérimentale?

We have recently suggested that vitamin A could protect against experimental lithiasis by repairing tubular membrane cells or protection against membrane damage caused by free radicals generated during experimental lithiasis. Although vitamin E treatment demonstrated no beneficial effect on stone formation, it promoted the repair mechanism by vitamin A during experimental lithiasis and by supported the hypothesis that oxalate crystals may be destructive to renal epithelium because they are large and irregular.

[Antilithogenic and litholytic action of vitamin A vis-a-vis experimental calculi in rats]. / Etude sur l'action antilithogène et litholytique de la vitamine A vis-à-vis de la lithiase expérimentale chez le rat.

Oxalate lithiasis was induced in control rats and rats previously given a vitamin A supplement for one week at the dose for 200 UI/d/kg body weight. Oxalate and calcium deposits in renal tissue measured 24 hours after the induction of lithiasis were found to be significantly lower in the vitamin A supplemented rats (p < 0.001 and p < 0.01) respectively). Renal function in these animals was also improved as compared with controls (p < 0.05). However, when vitamin A supplements were given for the same period and at the same dose, but after the induction of oxalate lithiasis, no difference regarding oxalate and calcium deposits was found between the two groups of animals. The same applied to renal function, which showed no improvement in the supplemented animals as compared with controls. These results suggest that vitamin A supplements have an inhibitory effect on lithogenesis but probably no litholytic action as such. The effect of vitamin A is probably related to its action on tubular cellular repair or an inhibitory effect on necrosis of these cells.

[Contribution of scanning electron microscopy in children with lithiasis]. / Apport de la microscopie électronique à balayage dans la lithiase infantile.

Infrared spectroscopy (IR) was used as the preferential method for determination of the composition of calculi and scanning electron microscopy (SEM) for observation of the IR shape. Our results show the role of SEM for visualisation of the internal ultrastructure and architecture of calculi in children. The authors confirm their previous hypothesis that phosphates favour the nucleation of other compounds, and demonstrate the presence of some trace elements which could play an important role in lithogenesis (eg Si).

Effets de l'administration d'un decocte de thymus capitatus sur la fonction renale et la lithogenese chez le rat

Parmi les plantes medicinales les plus utilisees en Tunisie; figure le thymus capitatus; plus connu sous le nom de thym. L'administration pendant deux semaines d'un decocte de thym ameliore la fonction renale et entraine des baisses significatives des concentrations renales en exalates; en urates; en phosphates et en calcium. Ces baisses semblent etre provoquees par les chutes des excretions urinaires de l'acide oxalique et urique et par l'elevation de la zinciurie. Une legere amelioration de la fonction renale a ete mise en evidence egalement chez les animaux traites. Ces resultats laissent supposer que le thym pourrait etre une plante de choix dans la prevention et peut etre aussi; dans le traitement des lithiases renales

[Calendula arvensis L. Impact of saponins on toxicity, hemolytic effect, and anti-inflammatory activity]. / Calendula arvensis L. Impact des saponines sur la toxicité, le pouvoir hémolytique et l'activité anti-inflammatoire.

The study of the chemical composition of Calendula arvensis var. eu arvensis Maire reveals the presence of saponins. These saponins confer a haemolytic property on the plant. In our work we have, first determined the saponin responsible for the haemolytic property; and then we have studied the impact of the saponins on the acute toxicity and the anti-inflammatory activity induced by carrhageenin oedema.

[Familial distal tubular acidosis]. / Acidose tubulaire distale familiale.

This study concerned a Tunisian family of 52 members. We have looked for distal tubular acidosis (D.T.A.) after we had discovered that 2 members of this family suffered from nephrocalcinosis with D.T.A. Twenty six of our patients (group I) suffered from D.T.A., 17 from confirmed metabolic acidosis with low urinary pH (5.22 +/- 0.25). Patients of latest groups may present a D.T.A. with intact capacity to lower urinary pH. Our literature review revealed 27 families composed of 228 patients.

High-affinity binding of testosterone in serum from normal developing chick embryos and during the graft-versus-host reaction.

The sera of developing chicken embryos contain high-affinity, low-capacity protein binding sites for testosterone. The affinities remain constant throughout development, with mean values for the association constants of approx. 3.6 X 10(8) M-1 at 25 degrees C, whereas the concentration of sites varies markedly as a function of age: from approx. 2 nmol/g serum proteins in 11-day embryos, it rises to a peak of approx. 5-8 nmol at 14-16 days, then drops to approx. 2.6 nmol at 18 days and only 0.8-1 nmol in adults. Testosterone binding is inhibited by corticosterone, progesterone and dihydrotestosterone, and is little affected by estradiol. The testosterone and corticosterone binding properties of chicken sera show close similarities: parallel ontogenic patterns; constant ratios, throughout development, of the equilibrium binding parameters of the two steroids; mutual binding inhibition. The evidence strongly suggests that the two activities are associated, at least in part, with a common protein carrier(s). In growing embryos which undergo a graft-versus-host reaction, elicited by the graft of adult spleen tissue at 9 days of age, the testosterone and corticosterone binding activities are significantly decreased. This decrease is due to a fall in the number of sites, whereas association constants are not affected. This is the first high-affinity, saturable, testosterone-binding property to be described in an embryonic serum.

Total and unbound cortisol-, progesterone-, oestrone- and transcortin-binding activities in sera from patients with myocardial infarction: evidence for differential responses of good and bad prognostic cases.

Day-of-admission sera from myocardial infarction patients (MI) and patients with cardiopathies other than MI (non-MI) were analysed for total and unbound cortisol (F), progesterone (P4), oestrone (E1), and corticosteroid binding activities (CBG). The MI who survived (n = 28) showed high increases of F, P4 and E1 compared to healthy controls. By contrast, the MI who died within 10 days of admission (n = 6) had unchanged F and less increased P4 and E1 than survivors. The non-MI (n = 6) had higher F and E1 than controls but normal P4. The unbound steroids were increased in all patients: however, the MI who died showed much smaller rises than survivors (P less than 0.001 for unbound F and E1 increases in survivors vs. deceased). The CBG activity was in all MI lower than in normals (P less than 0.001) but unchanged in non-MI. These results are discussed in terms of the potential significance of unbound plasma steroids as predictors of MI severity.

Serum inflammatory responses of transcortin binding activities and of total and free corticosterone and progesterone levels in developing rats: a kinetic approach.

The kinetics of the inflammatory responses of 5 serum parameters involved in specific protein-hormone interactions were studied, namely: transcortin (CBG) binding activities; total corticosterone (B), main ligand of CBG; unbound corticosterone (free B); total progesterone (P4), main competitor of B for binding on CBG; and the free P4. The studies were performed in developing animals, i.e. on rats given a single turpentine injection at 1, 10, 21 or 90 days of post-natal age. The responses showed similar trends at all ages, but age-dependent differences in kinetics and reactivities. Common characteristics were 3-5-fold increases of the hormone parameters as soon as 4-8 h after the injection, and 2-3-fold decreases in CBG activities. A remarkable age-dependent difference was the contrast of early CBG decrease in adults (4 h after turpentine) to the delayed occurrence of this reaction in immatures (8-24 h after turpentine). On the other hand, the increase of free B lasted for 72 h in neonates, but only 40 h in rats treated at 21 or 90 days. Age-dependent characteristics were seen also in reactivities: the peak increases in the hormone levels were highest in the young, while the peak decreases of CBG were most marked in the mature animals. The results suggest that the regulatory mechanisms governing the mutual effects of hormonal activities and CBG synthesis might depend on the stage of development.