PubMed Health⌕ Search

Biomedical subjects

I Kovács

Publications and source records attributed to I Kovács.

At least 19 recordsLinked to original sources
PubMed1992

[Laparoscopic cholecystectomy. Initial experiences].

Between February 1991 and July 1991, 74 laparoscopic cholecystectomies were performed. The number of all cholecystectomies during this period was 168. Two surgeons performed the operations. Stone in the common bile duct, old age, acute cholecystitis, severe obesity and heart rhythm disorders were regarded as contraindications. The duration of the operation was 45-210 min. (mean 127 min). The intervention was diverted to open cholecystectomy in 2 instances (2.7%). Early postoperative complications were observed in 2 cases (2.7%): biliary discharge and bleeding. Reoperation was necessary in one patient (1.3%) because of bleeding. There was no operative mortality. The mean duration of hospitalization was 5.6 days, and the mean postoperative period was 2.7 days. It is considered that, laporoscopic cholecystectomy can be carried out only by specialists in both bile surgery and laparoscopic techniques, provided that all the personal and technical conditions necessary for traditional cholecystectomies are at hand. Both medically and economically, the laparoscopic cholecystectomy results attain or even exceed those of the traditional open technique.

Adult↗
PubMed1992

Observations with a tri-phasic oral contraceptive (Tri-Regol) in everyday clinical practice.

The theoretical general principles of triphasic oral contraception are discussed in the introduction. This method, which is the closest to a physiological dosage, seems to be the most advantageous today. International data and the advantages and wide indication field of such "step-up" tablets are also discussed. The observations with the Hungarian Tri-Regol tablet are described in detail. In the course of controlling 355 cycles of 79 women pregnancy was not observed, the tablets were well tolerated by the women-except for some milder side-effects. The use of Tri-Regol needed not be discontinued due to, any unwanted effect or complication. The rate of intermenstrual bleeding was very low, and the triphasic therapy proved to be beneficial in case of manifesting cycle disorders or if the change of the contraceptive tablet became necessary because of intolerance. According to the opinion of the authors the oral contraceptive Tri-Regol is today's drug of choice due to its reliable ovulation inhibitory action, low hormone content, and favourable tolerability.

Adolescent↗
PubMed1992

Observations with Bromocriptin tablet.

Dopamine agonist Bromocriptin tablet has been used in 102 cases, partly for the inhibition of puerperal lactation, partly for the treatment of infertility accompanied by hyperprolactinaemia. On the basis of the clinical results and the changes of PRL level the drug was found to be very effective in both indications. Side-effects necessitating the discontinuance of treatment were not observed.

Adult↗
PubMed1991

Enantioselectivity at the physiologically active GABAA receptor.

A subfraction of cortical tissue from rat brain, containing membrane vesicles was prepared freshly with added protease inhibitors and antioxidant. The preparation was used to measure stimulation of transmembrane 36C1- flux and inhibition of bicuculline-sensitive [3H] muscimol binding by (+)-(S) and (-)-(R) enantiomers of dihydromuscimol at 30 degrees in physiological salt solution. Displacement of bound [3H]muscimol and stimulation of 36Cl- flux appeared in the 0.1-10 microM concentration range of the enantiomers, channel gating, however, required rather high concentrations. Degrees of enantioselectivity for channel gating, desensitization of and binding to GABAA receptors were estimated by the concentration ratios of dihydromuscimol enantiomers, [(-)-(R)]/[(+)-(S)], at the same level of response or displacement. Different enantioselectives were observed for channel gating (6 +/- 3), receptor binding (3 +/- 2) and desensitization (no selectivity). The low and concentration-dependent enantioselectives found for channel gating and receptor binding can be explained by desensitization and heterogeneity of GABAA receptors.

Animals↗
PubMed1991

Burkitt's lymphoma with 3;14 and 2;8 translocations simultaneously.

Burkitt's lymphoma of a ten-year-old boy with specific 8;14 and variant 2;8 translocations is reported. The post mortem diagnosis of Burkitt's lymphoma was based on histological picture and the cytogenetic findings of the tumor biopsy. The child died four days after clinical admission. Because of the rapid progression of the disease immunological and serological investigations could not be performed. Therefore several questions remained unclarified. It is supposed that in the patient's B-lymphocytes multiple transformation events occurred leading to the development of the polyclonal lymphoma, similarly to that described in transplant-associated lymphoproliferations.

Burkitt Lymphoma↗
PubMed1991

Decreased sensitivity of cytostatic drugs in glucocorticoid receptor-free acute myeloid leukaemia cells. Clinical and experimental observations.

Preliminary clinical observations have suggested that low cellular glucocorticoid receptor (GR) levels might have been connected with multidrug resistance in children with acute myeloblastic leukaemia (AML). To test this possibility, we have developed glucocorticoid resistant subclones of two recently established human myeloid leukaemic cell lines. The cause of glucocorticoid resistance was GR negativity in these subclones. GR positive parent cell lines or GR negative subclones were incubated for 1 h in the presence of Adriamycin, Cytosine-arabinosid, Etoposide or Vincristine, respectively. After short-term (1 h) incubation in suspension cultures cells were washed and plated in clonogenic agar cultures. Each anticancer drug was more potent against both GR positive parent cell lines than against the GR negative subclones. The results of this study suggest that the absence of GRs is a useful marker of multidrug resistance in childhood AML.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

[Cytogenetic studies in Wilm's tumor].

Chromosome analysis was on tumor cells and peripheral lymphocytes from three cases with Wilms' tumor (WT) carried out. In one of them WT was associated with aniridia, in the other two cases WT developed without any congenital malformations. Deletion in the short arm of chromosome 11 [del(11)(p13)] was found in the tumor cells such as lymphocytes in the patient with aniridia--WT association. The constitutional karyotype of other two patients proved to be normal. In the tumor cells of one of them a normal karyotype was found, while the other child had hyperdiploid karyotype. The role of chromosome 11p deletion, in respect of molecular biological knowledge in tumor genesis, is discussed. Results reported here suggest that children with aniridia associated with a constitutional deletion at the 11p13 locus have a high risk for developing WT and therefore require careful ultrasound follow up.

Chromosome Deletion↗
PubMed1990

[A case of hybrid acute leukemia in a a child].

Hybrid acute leukaemia is characterized by the presence of lymphoid and myeloid markers in a single cell or in different blast cell subpopulations of the same patient. Authors report on a case of a 14-yr-old girl with hybrid acute leukaemia. Immunofluorescent analysis revealed CD 14, CD 10, CD 19 and HLA-DR antigens in the cell suspension isolated from peripheral blood of the patient. Because of the excess of FAB M1 type blast cells, the patient was treated according to IGCI-1984 protocol. Remission was not achieved despite combined cytotoxic treatment and patient died within 4 weeks following admission. The poor outcome of the disease agrees well with literature data. Hybrid acute leukaemia represents a challenge for the clinical science.

Adolescent↗
PubMed1990

[Vitamin K 1 concentration and vitamin K-dependent clotting factors in newborn infants after intramuscular and oral administration of vitamin K 1].

Serum concentration of vitamin K1 and activity of vitamin-K-dependent factors II, VII, IX and X were determined before and after vitamin K1 administration in infants. The babies received vitamin K1 intramuscularly or orally. 12 hours after vitamin K1 treatment the mean concentration was increased in the groups receiving vitamin K1 intramusculary or orally, respectively. Serum level of vitamin K1 fell exponentially, the mean half life was about 30 hours in both groups. Activity of vitamin K-dependent clotting factors did not change significantly after intramuscular or oral vitamin K1 administration during the first four-five days of life. It was no direct correlation between the concentration of vitamin K1 and the activity of vitamin-K-dependent clotting factors. This study suggest that oral administration of vitamin K1 is as effective as the intramuscular route.

Administration, Oral↗
PubMed1990

[Prothrombin and acarboxyprothrombin activity in neonates after oral and intramuscular administration of vitamin K].

The effect of prophylaxis with oral or intramuscular vitamin K1 (Konakion) on the hypoprothrombinaemia and on the rate of detectable acarboxyprothrombin of full-term newborns was investigated. Factor II clotting activity, factor II activity by Echis carinatus venom, factor II protein concentration and acarboxyprothrombin were determined in four groups of breast-fed infants. In the untreated group and in the group where the babies received vitamin K1 orally at birth the factor, II clotting activity was decreased and the rate of acarboxyprothrombin positive cases was increased significantly (from 30% and 28% to 55% and 52% respectively) at the 3d and 5-7th days of age. By the other two groups where 1 mg vitamin K1 was given intramusculary or 2-3 mg vitamin K1 was given orally with the first milk-feed, the factor II clotting activity increased at 3d and 5-7th days of life. In these groups the rate of acarboxyprothrombin positive babies was reduced at 3d day of life from 36% and 35% (cord blood values) to 16% and 13% respectively, and there was found acarboxyprothrombin in none of the babies at 5-7th days of life. These findings support that vitamin K1 given orally at birth is ineffective to prevent vitamin K deficiency, but when it was given with the first feed orally to well, mature babies it seems to be enable to protect the early haemorrhagic disease of the newborns.

Administration, Oral↗
PubMed1990

Prognostic value of chromosome aberrations in childhood acute lymphoid leukemia (ALL).

Cytogenetic analyses were performed on 43 children with acute lymphoblastic leukemia (ALL) before starting the therapy. Evaluable metaphases were obtained in 26 cases (60.46 %). The prognostic value of the initial chromosome picture and that of the different non-cytogenetic prognostic features was studied. In 14 out of 26 children (53.85 %) clonal chromosomal aberrations were found. The prognosis in the normal and normal/abnormal groups was significantly better than in patients with only abnormal cells. They found the remission rate of the diploid and hyperdiploid groups to be better and the survival duration significantly longer than in the pseudodiploid patients. Studying the correlation between the cytogenetic and non-cytogenetic findings the diploidy and hyperdiploidy seems to associate with low risk factors, while pseudodiploidy with high risk factors. When opposite cytogenetic and non-cytogenetic prognostic parameters were associated, the outcome of disease was determined by the cytogenetic picture. In eight patients out of the 14 children with abnormal karyotype various specific aberrations were found. While patients with specific translocations had a poor prognosis, the prognosis of the patients with 6q- was relatively good. The findings support the necessity of chromosome examination in all the children with ALL at diagnosis in order to distinguish the poor risk patients from the good ones.

Adolescent↗
PubMed1990

Cell membrane fluidity in blast cells of children with acute leukaemia.

Plasma membrane fluidity has been investigated by determining steady-state fluorescence polarization (FP) of the apolar stain 1,6-diphenyl-1,3,5,-hexatriene in intact blast cells, separated from peripheral blood and bone marrow of children with various types of acute leukaemia. FP-values of blast cells taken before antileukaemic therapy were compared with FP-values of peripheral blood and bone marrow mononuclear cells separated from patients in complete remission as well as from control patients and from healthy volunteers. Moreover, fluorescence polarization measurements were also performed using blast cells of leukaemic patients on short-term single-drug prednisolone pretreatment. The results have shown that untreated blast cells have significantly lower FP-values than normal mononuclear cells of peripheral blood or bone marrow. No compartment difference has been observed within blast cells, while normal mononuclear cells from peripheral blood have significantly higher FP-values than bone marrow cells. FP-values of cells separated in remission or during prednisolone treatment do not differ from control values.

Acute Disease↗
PubMed1990

Examination of the rebound effect of biphasic oral contraceptives.

Attempt has been made to induce ovulation with temporary Anteovin administration, that is with the rebound effect following the discontinuance of treatment in 34 women with anovulatory cycles who suffered from functional sterility. Ovulation could be induced in 9 cases and among the women whose cycles had become biphasic 3 became pregnant and 2 delivered normal healthy babies before closing the study. The results proved that rebound effect may be expected even following the use of Anteovin which is satisfactory from the aspect of a future fertility in women taking the tablet for cotraception.

Contraceptives, Oral, Synthetic↗
PubMed1989

Nerve endings from rat brain tissue release copper upon depolarization. A possible role in regulating neuronal excitability.

Membrane vesicles from rat cerebral cortex were prepared and the functional response of the GABAA receptor was followed by monitoring GABA-activated influx of the radiotracer 36Cl- ion. CuCl2 decreased GABA-activated 36Cl- influx into synaptosomal membrane vesicles. The effect of Cu2+ was concentration dependent (5-500 microM CuCl2) and occurred with saturating (1 mM) as well as low (30 microM) GABA concentrations. A similar inhibition of the responses to muscimol (30 microM) was also observed with 50 microM CuCl2. In addition, release of copper from cortical synaptosomes and median eminence was followed by atomic absorption technique. An increased release of copper into the extracellular space was observed upon depolarization with 50 mM K+. A minimal concentration of copper was estimated to be 100 microM in the synaptic cleft. These findings suggest that copper may play a role in regulating neuronal excitability.

Animals↗
PubMed1989

Abnormalities of chromosome 1 in relation to human malignant diseases.

Chromosome 1 is known to often be involved in various malignant diseases. Its numerical and structural aberrations have been observed in chronic and acute leukemias and solid tumors as well. Recently five protooncogenes have been assigned to the long and short arms of chromosome 1. The frequent and nonspecific occurrence of chromosome 1 rearrangements in human tumors suggests that they play an important role in the pathogenesis and progression of these diseases. The frequency, types, and time of the occurrence of chromosome 1 aberrations and their relation to the stage of the disease were studied in 317 patients with various malignant diseases. In ten patients nonrandom aberrations of chromosome 1 were observed. Two patients had CML, two PRV followed by ANLL, and the remaining six patients suffered from ANLL, ALL, Burkitt lymphoma, MF, SMMoL, and IRSA, respectively. In six patients, total or partial trisomy of the long arm or of the whole chromosome 1 was present, and in three cases balanced translocations involving chromosome 1 could be found. In the cells of one patient a duplication of the centromeric heterochromatin was seen. We analyzed the breakpoints involved. Finally, the aberrations of chromosome 1 were almost always be observed at the terminal stage of the diseases.

Adult↗