Biomedical subjects

I Duncea

Publications and source records attributed to I Duncea.

6 recordsLinked to original sources

PubMed1999

Effects of parenteral pharmacological magnesium loading on insulin secretion in experimental thyrotoxicosis.

Thyrotoxicosis is characterised by decreased magnesium pool and also insulin resistance. The present study is evaluating the parameters of glucose metabolism under pharmacological magnesium loading in experimentally induced thyrotoxicosis, in rats. Insulin secretion was significantly increased in thyrotoxicosis compared to controls, expressing probably the status of insulin resistance due to thyroxine excess. After intraperitoneal magnesium infusion, plasma magnesium reached pharmacologically high concentrations and insulin secretion decreased significantly, but this decrease was not accompanied by alterations of glucose homeostasis. In controls, we also found a tendency towards the decrease of insulin secretion after magnesium loading, but it did not reach statistical significance. Thus, insulin secretion seems more sensitive to the inhibitory effects of magnesium overload in experimental thyrotoxicosis.

Animals↗

PubMed1996

Plasma fibronectin in overweight men and women: correlation with serum triglyceride levels and serum cholinesterase activity.

When compared with 67 age- and sex-matched normal weight control subjects, the 71 overweight patients displayed obviously higher levels of plasma fibronectin. For a similar body mass index (BMI) the 16 overweight men younger than 45 years had a significantly (P < 0.01) higher plasma fibronectin level (455 +/- 99.3 mg/l; mean +/- SD) than the 16 age-matched overweight women (351 +/- 105 mg/l) while there was no significant difference between the 22 overweight men (446 +/- 89.2 mg/l) and the 17 overweight women (475 +/- 111 mg/l) older than 45 years. Particularly high plasma fibronectin levels were noted in the five women with upper body (android) obesity. Plasma fibronectin was positively correlated with BMI, serum triglyceride concentration, plasma fibrinogen and serum cholinesterase activity. It is considered that metabolic disturbances related to upper body obesity may lead to an enhanced hepatic secretion of VLDL and of several plasma proteins including fibronectin.

Adult↗

PubMedDate not supplied

Parathormone and calcitonin secretion in endemic goiter.

The investigations performed on 160 females of adult age with goiter and clinical signs of spasmophilia followed up the serum and urinary calcium and magnesium. The calcitonin and parathormone circulating levels were also determined. Although the levels of serum and urinary calcium and magnesium appear normal in adult subjects with simple goiter, decreased levels of the circulating parathormone were confirmed in most cases. The values of circulating calcitonin were within normal limits. The moderate hypoparathyroidism noted is an indication of the possible association of "parathyroid dystrophy" with endemic goiter.

Adult↗

PubMedDate not supplied

Calcitonin secretion in thyroid insufficiency.

The level of circulating calcitonin was followed up in 30 patients with severe hypothyroidism, diagnosed clinically and by laboratory examinations. Four of the patients under study had goiter. The complex investigation of phosphorus-calcium metabolism, including radioimmunoassay of calcitonin was made under basal conditions and after calcium loading. The results revealed low basal urinary calcium excretion and an increased skeletal uptake of calcium after loading. Calcitonin secretion persisted in 8 of the patients under basal conditions and it increased after calcium loading in another 14 of them, accounting for the increased "skeletal avidity" for calcium. The persistence of calcitonin secretion supports an earlier clinical observation concerning the relative integrity of the skeleton in patients with hypothyroidism. In the hypothyroid patients with goiter the results do not differ from those obtained in the remaining patients.

Adult↗

PubMedDate not supplied

Calcitonin secretion in hyperthyroidism.

The level of circulatory calcitonin was determined by the RIA method in 45 hyperthyroid patients in evolution, before and after calcium stimulation or after pentagastrin injection. The basal calcitonin secretion was increased in only 7 of the 45 patients studied, exceeding 500 pg/ml. After a slow calcium loading the mean of calcitonin increased, but with variable individual values. The rapid calcium loading was not followed by significant increases after 30 minutes. After pentagastrin a secretory peak of over 1,800 pg/ml was obtained in 4/5 cases. Results point out the state of the calcitonin-secreting system in hyperthyroidism and its possible role in the skeleton protection in these patients.

Adolescent↗

PubMedDate not supplied

Patterns of urinary 17-ketosteroid fractions in hirsutism.

Fractionated 17-ketosteroids were determined in 60 females with hirsutism. The chromatographic method was adapted in the Oncological Institute of Cluj-Napoca. In 32 patients the idiopathic form of hirsutism was confirmed with normal results for all the fractions and only sometimes a slight rise of androsterone. In 18 patients an ovarian origin was affirmed; all of them had androsterone and etiocholanolone over normal limits. In ten patients, who had an adrenal origin of hirsutism the great values of DHEA (dehydroepiandrosterone) were observed. In one patient with virilizing adrenal tumour, both total 17-ketosteroids, and all fractions were much elevated DHEA being over 100 mg/24 hours.

17-Ketosteroids↗