Biomedical subjects

M Stojiljković

Publications and source records attributed to M Stojiljković.

At least 19 recordsLinked to original sources

PubMed2003

Age-related differences in MK-801- and amphetamine-induced locomotor and stereotypic activities of rats.

Changes in locomotor and stereotypic activities induced by an i.p. injection of either (+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)-cycloheptan-5,10-imine maleate (dizocilpine or MK-801; 0.3 mg/kg) or D-amphetamine sulfate (AMPH; 1.5 mg/kg) were studied in male Mill Hill hooded rats of different age. The following age groups of animals were considered: 28-30 postnatal day (PND)-old rats (peripubertal), 48-50 PND-old (pubertal), 3-month-old (adults), 12-month-old (middle-aged) and 24-month-old (aged). The motor response was measured by an automated animal activity measuring system. The obtained results showed that: (1) in contrast to AMPH, MK-801 induced more pronounced increases of both locomotor and stereotypic activities in peripubertal and pubertal than in adult and aged rats; (2) AMPH induced the same locomotor and stereotypic activity increase in pubertal, adult and middle-aged rats; (3) both AMPH and MK-801 led to a senescence-related decrease of motor activity. These data suggest that the balance of the glutamatergic and dopaminergic systems changes during aging. Such a change is important in understanding schizophrenia and the motor system decline observed in the later stages of life.

Aging↗

PubMed2003

[Reconstruction of large defects of the abdominal wall using dermal and synthetic grafts].

Large defects of abdominal wall (greater than 8 cm in diameter) related to different cause, are still difficult problem of modern surgery. The best results in order to obtain safe and permanent anatomical and functional abdominal wall integrity are reached by autogenous dermal and synthetic grafts. Controversies concerning quality of these procedures are still presents. Our work is based on two equal experimental groups of 20 Vister rats each, with large artificial abdominal wall defects: one treated with autogenous dermal graft, another with synthetic Mersilene mesh graft. The animals from both groups were sacrificed in previous planned time intervals (3rd, 7th, 14th and 48th days). Afterwards detailed microscopic and gross examination of abdominal wall reparation and quality of reconstructed abdominal wall defects had been performed. According to our results both methods are easy to be performed and safety surgical procedures. Overestimated usage of synthetic grafts should be diminished because of advantages of autologous dermal graft--availability, substitution of firmly fibrosis tissue and endurance against infection.

Abdominal Wall↗

PubMed2003

[Evaluation of the value of local protective methods using latex prosthesis and fibrin glue in colonic anastomoses].

In this experimental study on small animals (Wister rats) performed evaluation of local protective methods--latex prosthesis and fibrine adhesives--on colon anastomosis healing--prevention of dehiscency. Ninety experimental animals in whom segmental left colon resection was done, were divided into three groups of 30 animals. In the control group after segmental resection termino-terminal anastomosis with single-layer continuous suture was performed. In the second and third group with the same animals, anastomosis protection was performed with endoluminal latex prosthesis and extraluminal application of fibrine adhesives. In the postoperative course where the animals were monitored for 21 days in the control group, 3 (10%) died of acute diffuse peritonitis the cause of which was anastomosis dehiscency, in the latex prosthesis 2 animals (6.6%) died, while in the extraluminally applied fibrine glue group all animals survived. The results of this experiment demonstrate that local protective measures for colon anastomoses may produce better results, with fibrine adhesive administration as the best modality.

Anastomosis, Surgical↗

PubMed2002

[Use of fibrin glue in the prevention of leakage in pancreatico-jejunal anastomoses].

The aim of this study was to test the protective effects of fibrin sealing on the pancreatico-jejunostomy (PJA), the high-risk anastomosis following pancreas head resection. Experimental study was performed on the mongrel dogs, divided in two groups (20 animals each): Experimental group-with end to end "dunking" PJA, protected by temporary occlusion of the pancreatic duct with fibrin sealant/Tissucol/Immuno Ag/, while control group was without any protective procedure. The animals were followed 5 months in order to study: protective effects of such procedure on the PJA quantified with the percent of anastomotic leakage, effects of the exocrine secretion and effects the endocrine function Results: PJA leakage occurred in 13.33% in control group. No leakage was registered in experimental group. Biochemical, histological and electron microscopic study showed slight transitory elevation of amylase levels. Fibrin glue plug was dissolved and pancreatic juice output was reestablished 12th days postoperatively. Long term follow-up showed no damages of the endocrine and exocrine pancreas. Pancreatic duct occlusion with fibrin glue appeared to be an useful method in the prevention of pancreatico-jejunostomy leakage, without negative effects on the exocrine and endocrine pancreas.

Anastomosis, Surgical↗

PubMed2002

[Experimental and clinical possibilities of transplantation of the injured and totally devascularized spleen].

The most severe spleen lesions with conquasation and devascularisation of entire organ, when it is practically impossible to do any preservating surgical procedure, are the true indications for the transplantation of this extremely important immunological organ. We have performed the evaluation of the surgical procedure of heterotopic auto transplantation in the 30 dogs with severe spleen lesions. Simulation of totally devascularized spleen with the lesions of V degree was performed by disrupting all segmental blood vessels with deep and long longitudinal transhilar incision. During the 3 months follow-up period, animals were subjected to numerous explorations in order to macroscopically and histologically valuate the implant. In most cases (80-85%) implants had complete vitality with the preservation of normal tissue architecture, while 15-20% of implants had partial or total fibrosis. There were no mortality and no complications after this preservation procedure. The presence of fibrosis in some implants suggests that the implant preparation should be better performed and that transplantation of larger tissue volume is needed. Enriched with this experimental experience we have performed heterotopic auto transplantation in 2 patients with spleen lesion of V degree (car accident and injury at work) with very satisfactory results.

Animals↗

PubMed1998

Properties of Mg(2+)-ATPase rat brain synaptic plasma membranes.

In the present study distribution and enzymatic properties of ecto-Mg(2+)-ATPase were determined in synaptic plasma membrane (SPM) preparations isolated from the hippocampus, caudate nucleus and whole brains of female rats. Western blot analysis using anti-ecto-Mg(2+)-ATPase antibody revealed the association of Mg(2+)-ATPase with SPM prepared from all the three brain sources, yet the enzyme was most abundant in caudate nucleus membranes, being 30% and 22% more abundant than in the hippocampal and whole brain tissue SPM, respectively. The evidence is also presented that kinetic properties of the brain Mg(2+)-ATPase are not under the control of circulating sex steroids. It was confirmed that the enzyme is activated by millimolar concentrations of Mg2+ and that it cannot be effectively inhibited by known ATPase inhibitors. The most pronounced differences in kinetic properties observed were 2.5 fold higher apparent affinity for ATP and 59% higher specific activity of Mg(2+)-ATPase of the caudate nucleus as compared with the enzyme from the hippocampus. On the other hand, the apparent enzyme affinity for Mg2+ was almost equal in all SPM preparations tested. Taken together, our results show that ecto-Mg(2+)-ATPase is not uniformly distributed and differs in respect to affinity for ATP in rat brain regions, thus indicating its substantial role in the process of signal transduction via controlling the levels of extracellular ATP.

Animals↗

PubMed1997

Biochemical characterization of the hippocampal and striatal Na,K-ATPase reveals striking differences in kinetic properties.

The activities and basic enzymatic properties of Na,K-ATPase were examined in synaptosomal plasma membranes (SPM) prepared from rat hippocampus and striatum. A kinetic analysis showed profound differences in apparent affinities for ATP (Km) between hippocampal (1.21 mmol/l) and striatal (0.76 mmol/l) enzyme preparations, as well as in the corresponding Vmax values. However, physiological efficiencies were almost the same. The complex pattern of dose-response curves to ouabain indicated the presence of two high-affinity forms of Na,K-ATPase in the striatum ("very high-": Ki = 3.73 x 10(-8) mol/l and "high-": Ki = 4.21 x 10(-5) mol/l), and one high affinity form in the hippocampus (Ki = 6.6 x 10(-7) mol/l). In addition, both SPM preparations contained one low affinity form with similar Ki. The "very high-affinity" form had positive cooperativity for ouabain inhibition of Na,K-ATPase activity, in contrast to "high" and "low-affinity" forms, which exhibited negative cooperativity. The respective contributions of ouabain-sensitive forms to the total activity were estimated as 22%, 46%, 19% for the striatum and 36%, 45% for the hippocampus. These data clearly demonstrate striking differences in kinetic properties of the hippocampal and striatal Na,K-ATPase that may be due to the isoenzyme diversity and adaptation to specific physiological demands of the examined rat brain regions.

Animals↗

PubMed1996

Ganglioside GM1 and GM3 in early human brain development: an immunocytochemical study.

The distribution of GM1 and GM3 gangliosides in human brain development between gestational week (g.w.) 6 and 15 was demonstrated by an immunocytochemical approach using polyclonal anti-GM1 and anti-GM3 antibodies. The first appearance of GM1- and GM3-positive cells was recorded as early as in g.w.6. Both antibodies labeled the cells in the ventricular zone of the telencephalic wall, with radially oriented fibers toward the pial surface, which represent radial glia cells with glia fibers. The intensive GM3 immunoreactivity was also exhibited in proliferating cells in the ventricular zone between g.w.6 and 12. During the period from g.w. 12 to 15, characterized by a rapid multiplication of neurons and glia cells, an increased number of GM1- and GM3-positive cells was observed. Prominent GM1 ganglioside staining was observed at the surface of the cell bodies in the ventricular zone. Besides surface labeling in migrating cells, GM1 immunoreactivity was identified inside the soma in the regions of cortical plate and subplate. GM1 immunoreactivity was more pronounced on the membrane of neuronal cells migrating along radial glia fibers, especially at the contact site between neuronal and glial cells. The GM3 ganglioside was localized mostly inside the soma, showing a granular immunoreactivity pattern. Our observations confirm the presence of GM1 and GM3 gangliosides in neuronal and glial cells in early human brain development. The involvement, especially of GM1 ganglioside in glia-neuronal contacts during migration of neuroblasts to their final destination, as well as the presence of GM3 ganglioside in proliferative cells in the ventricular zone of the telencephalic wall was also recorded.

Brain Chemistry↗

PubMed1995

Changes in neuropeptide levels after brain damage in rats.

The physiological and pathophysiological roles of neuropeptides are still not clear. The aim of our study was to detect long lasting changes of vasoactive-intestinal peptide (VIP), somatostatin (SOM) and substance P (SP) contents in the rat cerebral cortex and hippocampus after brain lesion. The experiments were performed on groups of adult male Wistar rats. The first group consisted of animals with unilateral ablation of the sensorimotor cortex performed at the age of 60 days. The second group was a control one (rats of the same age but with an intact brain). Both groups of animals were sacrificed at the age of 90-105 days and radioimmunoassay was used to determine amounts of VIP, SOM and SP. The mean values of VIP levels were decreased significantly only in contralateral cortical areas, while there was an increase of SP in lesioned animals. Our results suggest that descrete changes in neuropeptide levels occur during restorative processes after brain lesion.

Analysis of Variance↗

PubMed1995

Effect of early cortical lesion on the acute model of epilepsy.

The experiments were performed in order to investigate the sparing of function following early postnatal cortical lesion in the acute rat model of epilepsy. Sensorimotor cortex was unilaterally removed at 9 and 10 days of postnatal age in lesioned animals, while control animals were only sham operated (at the same early stage of life) or non-operated (before implantation of the electrodes). Seizure activity was recorded by means of electroencephalograms at adult stage of life induced by parenteral administration of penicillin (1,000,000 I.U./kg, i.p.). Our results showed that when the cortical lesion was performed in infancy (on the contrary to the lesion performed in adulthood) there was no prolongation of seizure activity in an acute model of epilepsy.

Aging↗

PubMed1992

The effect of cortical lesion on systemic penicillin epilepsy in rats.

There is a certain recovery of function following brain damage, due to neuronal plasticity. The experiments were performed in order to investigate the effects of cortical lesion on seizural activity in rats induced by systemic application of penicillin. The sensorimotor cortex was unilaterally removed in the lesioned animals, while the control animals were only sham operated or non-operated (before implantation of the electrodes). Seizural activity was recorded by means of electroencephalograms before and after penicillin treatment (1,000,000 I.U./kg, i.p). Testing of penicillin started at least 30 days after cortical lesion. Seizural activity was characterized by spike and wave complexes accompanied by vigilance reduction and sometimes by mild myoclonic jerks in both control and lesioned animals. The early period (about 2 h after penicillin administration) with appearance of the spike-wave discharges with relative increase of the mean total electroencephalogram powers as well as the succeeding period 2.5-5.5 h after penicillin administration) with maximum number of spike-wave discharges did not differ in the electroencephalogram of the control and lesioned animals. The late period of penicillin effect (from 6-11 h after penicillin administration) with frequent spike-wave discharges and still large mean total electroencephalogram powers was observed only in lesioned animals. It is concluded that a cortical lesion destabilizes the brain function in the rat model of epilepsy induced by parenteral administration of penicillin.

Animals↗

PubMed1991

[Surgical treatment of diabetic foot syndrome].

This is a review of 365 diabetic cases with severe forms of syndrome of diabetic foot (SDF) surgically treated in period of 20 yrs (1970-1989) at the Surgical Hospital, University Clinical Center in Nis. Comparative analysis of the clinical material, divided into two groups, the former and the latter periods of ten yrs, revealed essential difference in surgical treatment of SDF where advantages of modern surgical approach to treatment of this acute and severe problem have been clearly evidenced. After establishing the role and importance of surgical therapy in a complex, multidisciplinary treatment of SDF; practical guidelines for everyday surgical practice have been recommended for achieving better results to be reflected in decrease of mortality, increased number of spared legs and feet, or, in cases where amputation cannot be avoided, successful rehabilitation and application of prosthesis in severe diabetic patients.

Diabetic Foot↗

PubMed1989

[Drainage of the pericystic cavity in echinococcosis of the liver].

The authors emphasize that echinococcosis is cosmopolitan parasitosis and liver is the most often target organ. The most common complications are summarized. At any slightest doubt of the liver infection, the authors recommend modern diagnostic tools (ultrasonography CT) in liver examination. They analyze their lo years experience (20 hepatal). The conclusion is that basic therapeutic procedure is removing of pericyst content with hydatid membrane and residual cavity is treated later. The authors accept updated biac of liver echinococcosis treatment (radical removing of pericyst performing typical or atypical resection, or total lobectomy in case of lobar destruction). However they point out that drainage operations (marsupialization, external drainage with rubber drain, irrigation-aspiration drainage, T-drainage and internal drainage omentopeksia, anastomosis of the cavity with jejunal lumen) still have their place and value in Surgery.

Drainage↗

PubMed1981

[Partial resection of the liver in the treatment of echinococcosis].

On the basis of reports' reviewed and authors' experience, in 118 patients with hydatid disease of the liver, 15 of whom (12%) have been treated by partial resection of the liver, it can be concluded that: - Partial resections of the liver represents a radical surgical procedure in the treatment of liver hydatidosis, - A surgical treatment of the liver hydatid disease requires a total extirpations of echinococcus cysts, as well as irreversibly damaged liver tissue itself, - These resections' methods should be carried out in definite indications, - In comparison with other, especially more conservative (surgical) procedures, resections reduce complications and shorten a hospitalization, - Because of technical difficulties concerning respective surgical procedures (in particular left or right lobectomy), one should always have in mind the relative benignity of the hydatid disease, operative risk, and that other less aggressive surgical methods exist. - Surgical departments applying these methods have to employ sufficient quantity of adequate blood, well trained and experienced surgeons and equipment.

Adolescent↗

PubMed1979