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M Lazarević

Publications and source records attributed to M Lazarević.

At least 19 recordsLinked to original sources
PubMed1996

[Disorders of phosphate, calcium and magnesium ion metabolism in chronic renal insufficiency].

In hundred patients with different stages of renal functional damage, including the controls of healthy persons we examined the disturbances of phosphate, calcium and magnesium ion metabolism during chronic renal failure (CRF) progression. We also determined the serum levels of regulatory substances, parathormone and 1.25 dihydroxyvitamin D3 in 43 pts. grouped according to their group, sex, age average and season (autumn-winter) distribution. We established actual renal compensatory mechanisms for all of substances we determined, which were involved in homeostasis preservation of those substances. Some characteristic changes in plasma substance concentration and renal mechanisms of their regulation during CRF progression, suggest the following conclusions. No substances have preserved body homeostasis, although renal compensatory mechanism were expressed by different size for any of them. Those disturbances very tightly correlate with the stage of renal functional deterioration, as well as the serum parathormone rising and serum 1.25 DHHC decreasing.

Adult↗
PubMed1996

[Pathogenic mechanisms of importance for the development of secondary hyperparathyroidism in chronic renal insufficiency].

Secondary hyperparathyroidism is a complex pathophysiologic event which we examined in hundred patients Sixteen of them belonged to the control with normal renal function, and the rest of them were categorised into four subgroups according to the actual level of chronic renal failure, determined by GFR a.i. by endogenous creatinine clearance. We determined the serum level of parathormone (C-PTH) and plasma concentration of phosphate and calcium in all of patients. In 43 of them we measured serum level of 1.25 dihydroxycholecalcipherol and ionised calcium. Our results suggested an important parallelism between parathormone hypersecretion (GFR +/- 58.3 ml/min), 1.25 dihydroxycholecalcipherol hypovitaminosis (GFR +/- 50.7 ml/min) and hypocalcemia (GFR +/- 47.7 ml/min) which connect them in very strong relationship. Even if secondary hyperparathyroidism in chronic renal failure is caused by numerous factors, it appears that the hypovitaminosis of 1.25 dihydroxycholecalcipherol with consequent hypocalcemia and phosphate retention acts as a main movement of this complex pathophysiology mechanism.

Adult↗
PubMed1996

[Levels of dihydroxyvitamin D3 and hydroxyvitamin D in patients with chronic renal insufficiency].

According to the aim of our research to find a regulatory of changes of the serum levels of 1.25 dihydroxyvitamin D3 and 25 OH D vitamin, we examined their serum concentration in 43 among 100 pts. with normal and impaired renal function with different stages of chronic renal failure (CRF). In all of 100 pts. we measured plasma phosphate and calcium concentration and endogenous creatinine clearance. The results of our research showed homeostasis abnormalities in all of parameters we examined. We found out that the serum 1.25 (OH)2 D3 levels decreased in early course of CRF, hypovitaminosis occurred when glomerular filtration rate reaches values equal or less than 50.7 ml/min. Hypovitaminosis of 25 OH D expressed in end-stage of CRF, while hyperphosphatemia was commonly seen in moderate CRF, when GFR became less than 28.6 ml/min. Hypocalcemia obtained when GFR was equal or less than 47.7 ml/min.

Adult↗
PubMed1988

Anaphylactic shock-induced conditioned taste aversion. I. Demonstration of the phenomenon by means of three modes of CS-US presentation.

A series of three experiments was conducted to investigate whether an anaphylactic response could induce a conditioned modification of behavior. Rats sensitized to ovalbumin were subjected to a conditioning trial in which the conditioned stimulus (CS; saccharin solution) signaled the presentation of the unconditioned stimulus (US; shocking dose of ovalbumin), eliciting the unconditioned response (UR; anaphylactic shock). In a subsequent two-bottle preference test, immunized rats given a CS-US pairing developed a conditioned taste aversion toward an otherwise preferred saccharin solution. The phenomenon of anaphylactic shock-induced conditioned taste aversion was found to be robust and resistant to extinction during the 6-day test period and was established employing three modes of CS-US presentation: (a) CS po, US ip; (b) CS po, US iv; and (c) CS iv, US iv. The most effective mode of CS-US presentation for producing anaphylactic shock-induced taste aversion was observed in Experiment 1 (CS po, US ip). Thus, aversive manifestations of anaphylactic shock can serve as afferent signals by which the immune system informs the central nervous system which in turn modulates behavior.

Anaphylaxis↗
PubMed1988

Anaphylactic shock-induced conditioned taste aversion. II. Correlation between taste aversion and indicators of anaphylactic shock.

Previous studies (V. J. Djurić, B. M. Marković, M. Lazarević, & B. D. Janković, 1987, in B. D. Janković, B. M. Marković, & N. H. Spector (Eds.), Neuroimmune interactions, pp. 561-568, New York: New York Acad. Sci.; B. M. Marković, V. J. Djurić, M. Lazarević, & B. D. Janković, 1988, Brain Behav. Immun. 2, 11-23) have shown that rats learn to associate the taste of saccharin with the induction of anaphylactic shock, thus exhibiting conditioned taste aversion (CTA) toward an otherwise preferred saccharin solution. The present experiment investigates the effect of unconditioned stimulus intensity (the amount of antigen used for the induction of shock) on CTA. Rats were sensitized to ovalbumin and subjected to a conditioning trial in which the conditioned stimulus (CS; saccharin solution given orally) signaled the presentation of the unconditioned stimulus (US; shocking doses of ovalbumin ranging from 0.5 to 3 mg given intraperitoneally). Behavioral signs, hematocrit, and rectal temperature were used for evaluation of anaphylactic shock. Twenty-four hours after the conditioning trial, rats were subjected to a two-bottle preference test between saccharin solution and water. Multiple regression statistical analysis revealed significant correlations among saccharin preference ratio, dose of antigen used for the induction of shock, behavioral signs of shock, rise in hematocrit, and fall in rectal temperature. A dose-dependent relation among saccharin preference ratio and physiological indicators of shock suggests that conditioned anaphylactic shock-induced avoidance behavior is functionally related to homeostatic factors involved in immune reactivity.

Anaphylaxis↗