PubMed Health⌕ Search

Biomedical subjects

N Petrović

Publications and source records attributed to N Petrović.

At least 19 recordsLinked to original sources
PubMed2006

[Hepatobiliary scintigraphy in evaluation of liver transplant function].

The aim of the study is evaluation of hepatocellular function, as well as morphology and patency of the biliary three of the liver transplants by dynamic hepatobiliary scintigraphy. The study was performed in 10 controls and 10 patients after orthotopic transplantation (up to two years). Sixty minutes dynamic acquisition (1 frame/min) was performed with scintillation camera after injection of 360 MBq 99mTc-diethyl- IDA. Hepatobiliary scintigrams were analysed for morphology, and parenchymal and hepatobiliary TA curves were generated and analysed as regard to the time to maximal acitivity (Tmax) and the time to half of maximum acitivity (T1/2). Uptake of the radiopharmaceutical was slightly but not significantly delayed (Tmax=18.5 +/- 2.9 min) in comparison to the controls (Tmax=14.2 +/- 3.4min), while excretion was significantly prolonged (T1/2=59.5 +/- 12.1 min) than physiological (Tmax=34.2 +/- 4.1min). Intrahepatic bile flow was nonsignificantly prolonged (Tmax=31.3 +/- 3.7 min) in comparison to the controls (Tmax=25.7 +/- 3.5 min) while extrahepatic one is high significantly prolonged (T1/2=89.0 +/- 14.3 min) than physiological (T1/2 =45.0 +/- 7.2 min). Biliary phase of hepatobiliary scintigraphy showed increased accumulation of radiopharmaceutical in the left (n=1) or right (n=2) hepatic duct. Radionuclide methods are noninvasive, and apear to be sensitive and valuable for the monitoring of liver transplants.

Biliary Tract↗
PubMed2005

[Radionuclide detection of Helicobacter pylori infection].

The aim is the assessment of the HP infection in stomach using breath test and comparison to other diagnostic methods, as well as following up the effect of therapy. In 83 patients with digestive discomfort rapid urease test, histology and breath test were performed, while in 25 patients with proven HP infection the effect of therapy was followed up using breath test and clinical findings. For rapid urease test and histology, samples were taken from antral mucosa. Breath test was performed after per oral administration of the capsule of 14C- urea (37 kBq) (Izotop, Hungary and Laboratory for radioactive isotopes, Vinca) which, in the presence of Helicobacter pylori breaks up to 14CO2 and NH3. Radioactivity was measured by beta counter in the exhaled air fasting and 30 minutes after ingestion of the capsule. According to our results, the rise of activity over 100% was considered positive. From 83 patients, 58 were breath test was positive, 24 negative and one equivocal. Fast urease test was in 54 positive, in 29 negative while histology was in 57 postitive and 26 negative. Findings of the breath and urease tests were in accordance in 93% patients while breath test and histology in 98% patients. During follow up of the therapeutic effects, breath test and clinical findings were in accordance in 98% patients. Breath test can be useful in diagnosis but is a method of choice in following up the patients after therapy for H. pylori infection, because it is non-invasive, fast and precise.

Breath Tests↗
PubMed2005

[Implementation of the radiolabelled antibiotic in the detection of orthopedic infections].

The aim of the study is detection and evaluation of the orthopedic infections using 99mTc-ciprofloxacin, radiopharmaceutical supposed to distinguish inflammation from infection. There were 15 true positive findings, 9 true negative, and two were false positive, while 1 was false negative. Sensitivity was 94%, specificity 82%, positive predictive value 88%, negative predictive value 90% and accuracy 89%. According to our results, scintigraphy with 99mTc-ciprofloxacin is a useful method for detection and assessment of exact localization of orthopedic infections, which might be useful for (differential) diagnosis, surgical treatment in due time as well as monitoring of the treatment of conservative therapy.

Arthritis, Infectious↗
PubMed2005

[Liver hemangioma blood pool as a function of time].

UNLABELLED: Aim of the study was to determine the time needed for establishing maximal labelled red blood cell concentration in hemangioma by scintigraphic semiquantitative blood pool estimation as a function of time. PATIENTS AND METHODS: Eleven patients (eight females and three males) with total number of fourteen liver hemangiomas have been examined. Nine of them had solitary lesions and remaininig two patients had two and three liver hemangiomas, respectively. All patients underwent blood pool scintigraphy 40, 60, 120 and 180 minutes after in vivo labelling of autologous red blood cells using 740 MBq of 99mTc. After correction for radioactive decay of 99mTc and back-ground correction blood pool indexes, as hemangioma/heart and liver/heart counting rate ratios, have been calculated. RESULTS: Mean blood pool indexes obtained 40-180 minutes after in vivo red blood cell labelling did not differ significantly (p > 0.05) neither in hemangioma (0.84-0.86) nor in liver tissue (0.55-0.58). In every acquisition time hemangioma blood pool index was substantialy higher than that of liver tissue (p < 0.01). CONCLUSION: The results of the study indicates that labelled red blood cells concentration reaches its plateau before 40th minute following in vivo labelling. The concentration difference between hemangioma and liver tissue also does not differ significantly after 40th minute of blood pool examination. In most patients blood pool scintigrams taken 60, 120 and 180 minutes following in vivo RBC labelling do not contribute to diagnostic value of the method.

Erythrocytes↗
PubMed2004

Effect of cold exposure on serum DBH and interscapular brown adipose tissue MAO activity in hypothyroid T3- and T4-treated rats.

As the indicators of sympathetic nervous system (SNS) function, the activity of serum dopamine-beta-hydroxylase (DBH) and interscapular brown adipose tissue (IBAT) monoamine oxidase (MAO) were examined in rats that were chemically thyroidectomized (TX), treated with thyroid hormones, and exposed to cold (4 degrees C). In TX animals, body temperature (bt) significantly decreased, and relative IBAT mass increased as compared with control, euthyroid animals, independent of the ambient temperature. The bt fall in TX cold-exposed animals was more severe, provoking hypothermia after 4 h. Under the same experimental conditions, the SNS function was enhanced as judged by the increased serum DBH and IBAT MAO activities. The treatment of TX animals with T(4) and T(3) re-established the temperature (bt was at the level of controls) and sympathetic homeostasis (DBH activity was at the level of controls) in animals maintained at room temperature but not in those kept under cold conditions. T(4) and T(3) did not affect IBAT MAO activity of TX rats: It remained significantly above the control values whether the animals were maintained at room temperature or exposed to cold. In conclusion, the IBAT of TX cold-exposed rats is incapable of responding to the enhanced thermogenic needs despite the increased SNS activity and thyroid hormone substitution.

Adipose Tissue↗
PubMed2003

Thyroxine and tri-iodothyronine differently affect uncoupling protein-1 content and antioxidant enzyme activities in rat interscapular brown adipose tissue.

The activity of the antioxidant enzymes copper-zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD) and catalase (CAT), as well as mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH) activity, uncoupling protein-1 (UCP1) content, catecholamine degrading enzyme monoamine oxidase (MAO) activity and malonyl dialdehyde (MDA) concentration were studied in rat interscapular brown adipose tIssue (IBAT). Rats were treated with either thyroxine (T4) or tri-iodothyronine (T3) for five days and then exposed to cold (4 degrees C, 24 h) or housed at room temperature (22 degrees C). Under basal conditions, T3 treatment significantly increased UCP1 content and MnSOD activity whereas CuZnSOD, CAT and MAO activities were significantly decreased. Thyroxine treatment significantly decreased IBAT CAT activity while MDA levels markedly increased. Cold exposure induced a significant augmentation of UCP1 content and MnSOD and mGPDH activities only in animals that were rendered hyperthyroid by T4 treatment. In T3-treated animals acutely exposed to cold stress, MDA concentration, an indicator of lipid peroxidation, was significantly higher compared with that of T3-treated animals housed at room temperature. However, in T4-treated animals, MDA concentrations were markedly lower. These results show that T4 and T3 differently affect IBAT parameters studied not only under basal but also under cold-stimulated conditions.

Adipose Tissue, Brown↗
PubMed2003

[Detection of abdominal infections using radio-labeled antibiotics].

The aim of the study is detection of the abdominal infective foci using 99mTc-ciprofloxacin, radiopharmaceutical supposed to distinguish inflammation from infection. Twenty-one patient was investigated. There were 11 true positive findings, 7 true negative, two were false negative, while 1 was false positive. Sensitivity of the method was 79% and specificity 91%. According to our results, scintigraphy with infection is a useful method for detection and assessment of exact localization of deep seated bacterial infections, which might be useful for (differential) diagnosis, surgical treatment in due time as well as monitoring of the treatment of conservative therapy.

Abdomen↗
PubMed2003

[Indium 111-labeled antibodies in the detection of colorectal carcinoma].

The aim of the study is detection of the recurrences and metastases of colorectal carcinomas using (111)In labelled antibodies B72.3 in 14 patients. With tomography, we can access better distinction of tumour in comparison to other structures and estimation of its size. Other imaging methods (CT, US) have advantage in detection of liver metastases, while immunoscintigraphy is more specific for the assessment of malignant abdominal tumours and extrahepatic metastases. The first results point out that Oncoscint CR-103 can be useful in diagnosis of recurrences and metastases of colorectal carcinoma, viability assessment after radiotherapy and in the choice of the adequate surgical treatment in dependence of the spread of the disease.

Adenocarcinoma↗
PubMed2001

[Study of blood flow in liver hemangiomas using radionuclide angiography].

Hepatic radionuclide angiography (HRA) is a recognised method of investigation of liver blood flow disorders caused by: diffuse and focal diseases of liver parenchyma or disorders of blood flow in extrahepatic liver vessels. Hepatic perfusion index (HPI) based on Sarper's slope method is significantly lower in patients with e.g. liver cirrhosis, malignant primary and metastatic liver diseases and portal vene thrombosis, but not in patients with benign focal liver leasions. Determined in liver as a whole, HPI is a sensitive indicator of the presence of malignant liver tumours, but is within normal range in patients with hepatic hemangioma. The aim of the study was to investigate characteristic of blood flow in hemangioma itself, separately from but in relation to the liver blood flow, using hepatic radionuclide angiography. We have examined 12 patients with liver hemangioma confirmed mainly by positive 99mTc-labeled red blood cell scintigraphy, which diagnostic specificity for liver hemangiomas is near 100%. 8/12 hemangiomas resulted in photopenic areas on angioscintigrams, indicating lower blood flow, and rest were isoactive to surrounding liver tissue. Regions of interest have been delineated around the photopenic areas (hemangiomas) and surrounding liver tissue. Time-activity curves have been generated and slope of the fitted hepatic artery and (portal) venous portions of the hemangioma and liver curves have been determined. Perfusion indexes of hemangioma (PIH) and liver (HPI) have been calculated from the slopes, expressing portal venous flow as a portion of entire blood flow to the region. In addition, times of arrival and transit of intravenous bolus of 99mTc-pertechnetate through the hemangioma and liver tissue have also been derived from time-activity curves. Slope of the venous portion of the hemangioma time-activity curve is significantly lower then that of the venous portion of the liver curve (p < 0.01). So that, perfusion index of hemangioma (PIH = 0.34 +/- 0.12 (mean +/- SD) is significantly lower then hepatic perfusion index (HPI = 0.57 +/- 0.08) (p < 0.05). Bearing in mind interference of superimposed liver activity with that of hemangioma, these results indicate that liver hemangiomas are dominantly if not exclusively irrigated by hepatic artery branches. There are no data regarding relation between arterial and venous blood flow in liver hemangiomas determined by HRA. Obtained results are in harmony with arteriography data which confirm slow arterial blood flow through hemangiomas. Portal venous inflow of some angiomatous liver lesions in infants and children, and arterio-portal shunting in hemangiomas have been rarely reported. Results of this study indicate that regional determination of perfusion index and other HRA parameters in patients with focal liver lesion enables differentiation between tissues with different intensity and pattern of blood flow. The method could be used in examination of vascularisation pattern of other focal liver lesions.

Erythrocytes↗
PubMed2001

The activity of antioxidant enzymes and the content of uncoupling protein-1 in the brown adipose tissue of hypothyroid rats: comparison with effects of iopanoic acid.

The activity of antioxidant enzymes, copper-zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD) and catalase (CAT), as well as that of the mitochondrial FAD-dependent alpha-glycerophosphate dehydrogenase (alpha-GPD) in the rat interscapular brown adipose tissue (IBAT) were studied after the treatment with methimazole (MMI) for three weeks or with iopanoic acid (IOP) for five days. Besides, the mitochondrial concentration of uncoupling protein-1 (UCP-1) and the activity of catecholamine degrading enzyme monoamine oxidase (MAO) in the IBAT as well as the activity of the catecholamine synthesizing enzyme, dopamine beta-hydroxylase (DBH) in rat serum were examined. Judging by the significantly enhanced level of serum DBH, which is an index of sympathetic activity, and that of IBAT MAO, the increase in MnSOD and CAT activities in the IBAT of hypothyroid (MMI-treated) rats seems to be due to elevated activity of sympathetic nervous system (SNS). However, CuZnSOD activity is not affected by SNS. On the contrary, IOP, which is a potent inhibitor of T4 deiodination into T3 producing "local" hypothyroidism, did not change either SNS activity or activities of IBAT antioxidant enzyme. However, both treatments significantly decreased IBAT UCP-1 content and alpha-GPD activity suggesting that the optimal T3 concentration in the IBAT is necessary for maintaining basal levels of these key mitochondrial parameters.

Adipose Tissue, Brown↗
PubMed2001

[Evaluation of enterogastric reflux in relation to functional status of the gallbladder].

The aim of the study was estimation of the relation between the gallbladder (GB) motility function and the presence and quantity of enterogastric reflux (EGR). We investigated 172 patients with: physiological GB function (filling and emptying)(FGB), impaired GB function (prolonged filling and ejection fraction < 45%) and afunctional gallbladder (AGB)(without visualization). The study was performed during 90 min (1 f/min) after i.v. application of 185 MB 99mTc-dietil IDA. After 30 min. test meal was given while at the end stomach was marked. According to the parameters from time activity curves over stomach and hepatobiliary system, the index of ERG was calculated, while GB filling and ejection fraction were estimated from the GB time/activity curve. We can conclude that EGR occurs more frequently in the patients with afunctional GB in comparison to those with functional and decreased motor function. Also, EGR quantity is in correlation with the impairment of the GB function.

Duodenogastric Reflux↗
PubMed2001

Aortal aneurysm as a cause of ileus.

A 62-year-old patient presented with flatulence, abdominal distension and other symptoms of ileus. Roentgenographic finding found compression on duodenum. Blood pool scintigraphy ((99m)Tc erythrocytes) showed aortal aneurysm, while simultaneous gastric emptying study with liquid meal ((99m)Tc-S-colloid) showed dislocation of duodenum and compression from abdominal aortal aneurysm.

Journal Article↗
PubMed1997

Activities of antioxidant enzymes and monoamine oxidase-A in the rat interscapular brown adipose tissue: effects of insulin and 6-hydroxydopamine.

The effects of different doses of insulin (INS) (0.4 or 4.0 IU/kg body mass, i.p., for 3 hr) and 6-hydroxydopamine (6-HDA) (100 mg/kg., i.p.) on the activities of antioxidant enzymes--copper-zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD), catalase (CAT) and catecholamine degrading enzyme monoamine oxidase (MAO-A)--in the rat interscapular brown adipose tissue (IBAT) were studied. In vivo 6-HDA administration, which induces the destruction of sympathetic nerves, markedly reduced IBAT CuZnSOD activity but did not change MnSOD and CAT activities. However, the low dose of INS, which did not induce hypoglycemia, significantly increased the activity of both IBAT mitochondrial enzymes (MnSOD and MAO-A) of control rats. This INS effect on MnSOD was abolished by 6-HDA. On the contrary, CuZnSOD activity was markedly reduced under the influence of INS in both control and 6-HDA-treated rats, whereas for the maintenance of the control level of this enzyme activity, the intact sympathetic nervous system (SNS) is necessary. INS, independent of the dose applied, did not affect CAT activity in control rats, whereas only low INS dose increased the activity of this enzyme in 6-HDA-treated rats. The results indicate that the stimulatory effect of INS on the IBAT mitochondrial enzymes studied is dose dependent and in the case of MnSOD is mediated by SNS. However, the depression in the activity of CuZnSOD is independent of the above-mentioned factors.

Adipose Tissue, Brown↗
PubMed1987

The effect of the rat-cyclophosphamide serum on the rat hematopoietic tissue recovery, previously damaged by cyclophosphamide or by gamma-irradiation.

The effect of post-cyclophosphamide serum (post-CY serum) humoral activity in vivo, on the rat hematopoietic regeneration after damage either by cyclophosphamide (CY) or by gamma-irradiation was investigated. Three experimental groups of rats were studied. The first group was treated by a single high dose of CY (200 mg/kg), the second group was whole body irradiated by 6.5 Gy, and the third group was whole body irradiated by 3.5 Gy. Each group was subdivided into three subgroups. The first among subgroups received immediately after damage 0.5 cc post-CY serum, the second received 0.5 normal rat sera per animal. The third subgroup of rats was used as control. Post-CY sera were collected from the Wistar rats, 2.5 months old 48 hours after the treatment by high single dose by CY (300 mg/kg). Post-CY serum activity in comparison to normal serum activity was evaluated in vivo conditions. In order to take samples of peripheral blood, spleen and bone marrow, the animals were sacrificed 24 hours, 48 hours, 72 hours and seven days after treatment. The assessment of post-CY sera effect is accomplished by measuring of the proliferative capacity of splenic, as well as bone marrow cells, and by means of the RBC and WBC counts. The results obtained indicate substantial stimulative and proliferative activity of the post-CY sera, when compared to normal sera, particularly in the animals previously damaged with CY.

Animals↗
PubMed1982

Susceptibility to proteolysis of thyroglobulin from rats and guinea-pigs treated with excess iodide.

The effect of excess iodide on proteolysis of in vivo 125I-labelled thyroglobulin (Tg) from rats and guinea-pigs was investigated in vitro using preparations of thyroid lysosomes and exogenous proteases (Pronase). Lysosomes were obtained by centrifugation of pig thyroid homogenates. This lysosomal preparation induced maximal proteolysis of Tg at pH 3.6 to 4.6 and was stimulated by KCl. Treatment of rats with excess iodide for up to 28 days had no effect on the proteolysis of Tg by lysosomes or Pronase. Decreased resistance of Tg to proteolysis by lysosomes and pronase was observed in guinea-pigs treated with excess iodide for 3 days, whereas Tg from guinea-pigs treated for longer time periods had increased resistance to proteolysis. This difference in the susceptibility to proteolysis of Tg provides an explanation why long-term administration of excess iodide is goitrogenic in guinea-pigs but not in rats.

Animals↗