Biomedical subjects

Z Poljaković

Publications and source records attributed to Z Poljaković.

At least 19 recordsLinked to original sources

PubMed1992

Changes in coagulability of blood in patients with cerebrovascular disease in various meteorological situations.

The authors are dealing with the influence of meteorological factors on vascular diseases, primarily on patients with cerebro-vascular disturbances. The parameters mentioned in some studies are also presented in the introduction. There are still few studies by means of which it can be enlightened what happens in the human body affected by atmospheric disturbances. Therefore the basic intention of this study was to come up with answers to at least some segments of this complex problem. A group of patients with cerebrovascular symptoms and signs was chosen for examination. Tests were carried out during cold and warm front passages in anticyclonal situations and low gradient pressure fields within 47 days. In the first stage the tests were carried out only in one day and later for three consecutive days. Meteorological reports are given too. As for medical parameters, the following were controlled: the neurology status, blood pressure, blood test, ECG, REG. The coagulum was regularly checked. The examination was carried out in 12 male and 14 female patients, the age range 43-78. On the basis of the tests, the authors concluded that the most significant changes were noticed in the coagulum and thromboelastogram. According to the results, these changes are manifested during the cold front and during the cold spell caused by it. The findings point to a significant increasing of the thrombocyte aggregation and partly the aggregation index, which can be clinically manifested as the patient's health aggravation. Although other parameters of coagulation did not show significant changes, it cannot be deduced whether they are susceptible to the circumstances in the atmosphere or not.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Vimentin and glial fibrillary acidic protein expression in relation to neoplastic cell differentiation in glial tumors.

In the present work the expression of vimentin and glial fibrillary acidic protein (GFAP) was determined in homotypic, transitional and heterotypic astroglial neoplastic areas and gemistocytes. The expression of these intermediate filament (IF) proteins within oligodendroglial neoplastic cells was determined as well. The intensity of vimentin and GFAP immunoreactivity as well as the number of immunoreactive cells within astroglial areas of different grades of differentiation were different. While there was no immunoreactivity within heterotypic areas, transitional areas and gemistocytes mainly show the same intensity of immunoreactivity and number of immunoreactive cells for both analyzed IF proteins. Within homotypic astroglial areas the number of GFAP positive cells and intensity of GFAP immunoreactivity were higher than the same vimentin parameters. It is well known that vimentin and GFAP may form heteropolymers both in vitro and in vivo. Transitions in vimentin/GFAP expression reflect not only normal development of astroglial cells but occur also with the induction of neoplastic process. Our results suggest that immunoreaction intensity and number of vimentin or GFAP immunoreactive cells correlates with the degree of differentiation of specific neoplastic cell populations. It is suggested that transitions in vimentin and GFAP expression occur in the course of neoplastic progression presumably by the modulation of their incorporation into the same IF system according to the degree of neoplastic cell differentiation.

Brain Neoplasms↗

PubMed1991

The clinical picture of rabies in a child.

An eight-year-old boy developed rabies 31 days after having been scratched by a dog and died 9 day later. Intensive supportive medical treatment was complicated by apnea, cardiac arrest, hypotension, increased secretion of antidiuretic hormone and severe hypoproteinemia. The treatment with intramuscular human antirabies immunoglobulin (HRIG) 2400 I.U. and intrathecal 1200 I.U. in combination with intramuscular interferon alpha 4 million I.U. was given every second day. The diagnosis of rabies was confirmed before death, on the third day of the disease, by direct fluorescent antibody staining of the saliva and cerebrospinal fluid for viral antigen. At the autopsy, the brain tissue specimens were tested for the presence of the virus by inoculation into the suckling mice brain and for the viral antigen by direct fluorescent antibody method. The brain tissue specimens collected at autopsy were also tested for virus by direct fluorescent antibody method.

Child↗

PubMed1991

Correlative pathology of subdural hematoma with computerized tomography.

Subdural hematoma (SDH) develops as a result of bleeding in the subdural space. According to nowadays accepted division, three groups of subdural hematomas can be differentiated: acute, subacute and chronic. The time elapsed from the moment of the occurrence of the hematoma to the moment when it was diagnosed is the main factor for determining the stage of SDH. However, for the above-mentioned types of SDH, this time differs depending on the author reporting it. Subdural hematoma is most often diagnosed by means of computerized tomography (CT). This method is safe and reliable, giving the exact diagnosis in more than 90% of cases. According to the basic principle of the concept of "living pathology", the knowledge of histological appearance of an investigated lesion is essential for the diagnostic interpretation of this lesion in neuroimaging methods. Very few authors studied the histological picture of subdural hematoma. The only structure which was histologically examined in details was the subdural neomembrane. Studies correlating histological picture of SDH and its appearance on CT scans have not been carried out until now. In this work such a correlation was made, and some regularities connecting these two methods were pointed out. Hyperdense picture of SDH on CT scans represents a hematoma containing almost only erythrocytes and erythrocyte-fibrin component being formed. Hypodense picture of SDH on CT scans represents a hematoma containing fibrin and inflammatory cells. Hematomas of mixed density on CT scan in all cases contained a neomembrane. Obvious histological differences between the mentioned types of subdural hematoma have led to the conclusion that chronic subdural hematoma is not the last stage of an "old" acute SDH. Chronic and acute subdural hematomas are different entities, considering their etiopathogenetic and clinical picture, and especially their CT and histopathological appearances.

Adolescent↗

PubMed1990

Medullomyoblastoma.

A case of medullomyoblastoma, arising in the cerebellar vermis of a five-year-old boy, is presented. The light and electron microscopic features of the tumor are described and compared to other published cases. Within typical medulloblastoma areas light microscopy revealed signs of neuroblastic differentiation thus indicating its neuroepithelial origin. No signs of glial differentiation were found. Myogenic tumor component formed irregular, distinctly separated islands although some intermingling of two cell types was observed at the borders between the two zones. Within the myogenic tumor component, electron microscopy revealed rhabdomyoblastic elements in different stages of differentiation, frequently forming small groups encompassed by the same basement membrane. No indication of a common host cell for two cell lines was observed. No mesenchymal elements other than muscle, and no indication of possible teratoid origin of this tumor were observed. Considering histogenesis of muscle elements within this neuroepithelial tumor, the origin from multipotential neural-crest-derived ectomesenchymal cells seems the most appropriate one.

Cerebellar Neoplasms↗

PubMed1990

Dysplastic granulo-molecular hypertrophy of the cerebellar cortex (L'hermitte-Duclos disease): report of three cases.

In this paper three cases with peculiar disease of the cerebellar cortex are presented. The disease is well known as L'hermitte-Duclos disease (LDD), but nowadays it is also called "dysplastic granulo-molecular hypertrophy of the cerebellar cortex" according to the modern theories of its etiology. Curious changes of the cerebellum in LDD are probably the result of a combination of delayed migration of Purkinje cells which occurs during the intrauterine period of cerebellar development, and of reactive hypertrophy of granular cells. Presented cases of L'hermitte-Duclos disease are, according to the literature, more or less typical by their clinical appearance and by their histological findings. Our electromicroscopical data support the findings of those authors who found only axodendritic sinapses on the hypertrophied ganglion cells, according to the idea that those cells are originally granular cells of the cerebellar cortex. CT scan of all our patients revealed parallel, worm-like, hyperdense formations in a hypodense process of the cerebellum. The same picture existed in some other described patients, but attention was paid to it. We consider this picture on the computed tomography to be characteristic, if not even patognomonic for the L'hermitte-Duclos disease, which gives us an entirely new scientific contribution in the process of the diagnosis of this peculiar disease.

Adult↗

PubMed1990

Natural killer (NKH-1+) cell number and activity in health and disease.

The proportion of lymphocytes bearing the NKH-1 membrane marker (a natural killer-cell marker) was determined by flow cytometric analysis of the peripheral blood of 40 healthy individuals, 45 patients with multiple sclerosis and 19 with other neurological diseases. Natural killer (NK) cell activity was determined in parallel. It was shown that NKH-1-positive cells were more abundant in the lymphocytic than the mononuclear cell window on the flow-cytometric granularity versus cell size two-parameter display. NK-cell concentration did not correlate with NK-activity in any of the three groups of individuals studied. However, when the data for the three groups were compounded (i.e. when the number of samples analysed exceeded 100) significant correlations were disclosed. No correlation was found between age and NKH-1-positive cell number or activity in any of the three groups of subjects. High variability of the number and activity of natural killer cells in different individuals, and imprecision of phenotyping of the entire pool of NK-cells by means of a single marker, appeared to be responsible for poor correlations of NK-cell number and activity as observed in the study.

Adult↗

PubMed1989

Natural killer cell number and activity in multiple sclerosis.

Natural killer (NK) cell percentage among cells appearing in lymphocytic flow-cytometric gate, and their concentration per unit volume of peripheral blood, as well as NK-cell in vitro activity, were determined in 45 patients with multiple sclerosis (MS, 34 with definite and 11 with probable diagnosis). Two age- and sex-matched control groups consisted of 27 healthy individuals and 19 individuals with other neurological diseases, respectively. NK cells were identified on the basis of their reaction with monoclonal antibody NKH-1, and NK-activity on the basis of their spontaneous killing of K-562 erythroleukemia target cells with mononuclear cells from peripheral blood. MS patients were analyzed in regard to the phase (active, stable inactive, stable progressive) and course (remittent, remittent-progressive, progressive) of the disease. In general, MS patients tended to have both lower number and activity of natural killer cells than either of the two control groups. A statistically significant decrease was found for the concentration of NKH-1+ cells in the blood of all MS patients, for the number of lymphocytes in the blood of patients with remittent course of the disease, and for the number of NKH-1+ cells in the blood of patients with progressive course of the disease. It appeared that more profound defects were associated with the progression of the disease; NK-cell number always appeared more affected than NK-cell activity. In MS patients, NK-cell activity correlated significantly with NK-cell percentages among lymphocytes but poorly with the concentration of NKH-1+ cells in the blood. In healthy controls, neither of the two correlations was significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Detection of IgG oligoclonal bands in unconcentrated CSF by isoelectric focusing in ultrathin polyacrylamide gel, direct antiserum immunofixation and silver nitrate staining.

Isoelectric focusing of proteins in ultrathin polyacrylamide gel (0.4 mm), followed by direct immunofixation with monospecific antisera and silver nitrate staining, is a highly specific, sensitive and simple method for the detection of oligoclonal IgG in unconcentrated CSF samples. The ultrathin polyacrylamide gels have several advantages, i.e. significantly smaller amounts of reagents are required, and thinner gel can be more efficiently cooled, resulting in higher resolution and shorter running, washing, staining and destaining times. Direct immunofixation in the gel, a time-saving and simple step, increases the sensitivity and specificity of the method. We reduced the samples to 5-10 microliters. For the present method, the optimal concentration of IgG was 0.025-0.030 g/l. It is possible to detect oligoclonal IgG bands at an IgG concentration corresponding to the applied amount of 80-100 ng. In our testing of this method, oligoclonal bands in CSF specimens were clearly demonstrated in 33 (97%) out of 34 patients with definite multiple sclerosis, in 16 (42%) out of 38 patients with infectious diseases of the central nervous system and in 11 (18%) out of 58 patients with other neurological disorders. The method appears to be a useful alternative for the demonstration of oligoclonal IgG bands in unconcentrated CSF samples, and can be recommended for use in the CSF laboratory routine.

Central Nervous System Diseases↗

PubMed1989

Detection of oligoclonal IgG bands in unconcentrated CSF in multiple sclerosis and other neurological diseases by isoelectric focusing on ultrathin-layer polyacrylamide gel immunofixation and silver staining.

Isoelectric focusing of proteins (IEF) in ultrathin-layer polyacrylamide gel (0.4 mm, PAG), followed by direct immunofixation with monospecific antiserum and silver staining, is a highly specific, sensitive and simple method for the demonstration of oligoclonal IgG in unconcentrated cerebrospinal fluid (CSF) samples (5-10 microliters). For the present method, the optimal concentrations of IgG in CSF samples are about 0.025-0.030 g/l, corresponding to the applied amount of 125-150 mg. In our testing of this method, oligoclonal IgG bands in CSF specimens were clearly demonstrated in 52 (96%) of 54 patients with clinically established definite diagnosis of multiple sclerosis (MS), in 4 (40%) of 10 patients with infectious diseases of the CNS, and in 9 patients (25%) of 38 with other neurological diseases. Abnormal patterns were also demonstrated in the serum of patients with MS (43%). Intrathecally synthesized IgG was mathematically calculated in 43 (80%) out of 54 patients with MS. This method appears to be a useful alternative for the demonstration of oligoclonal IgG bands in the unconcentrated CSF, especially when questionable or negative results arise by routine electrophoretic technique for oligoclonal bands detection.

Humans↗

PubMed1988