Biomedical subjects

J Kowalewski

Publications and source records attributed to J Kowalewski.

At least 19 recordsLinked to original sources

PubMed1991

Identification of metabolic pathways of the lipid peroxidation product 4-hydroxynonenal by enterocytes of rat small intestine.

The cytotoxic lipid peroxidation product 4-hydroxynonenal (HNE1) is rapidly metabolized in enterocytes. The degradation of HNE and other aldehydic products of lipid peroxidation processes seems to be an antioxidative defense system. The metabolism of HNE was studied in suspensions of rat enterocytes at 37 degrees C, pH 7.4 and at initial HNE concentration of 100 microM. About 70% of the HNE were degraded within three minutes of incubation. Main products of HNE which were identified in enterocytes were the glutathione-HNE-1:1-conjugate, the hydroxynonenoic acid and the 1,4-dihydroxynonene. Furthermore, the formation of metabolites of the tricarboxylic acid cycle is suggested. The quantitative share of HNE binding to proteins was low with about 1% of total HNE consumption after three minutes of incubation.

Aldehydes↗

PubMed1991

[Chemotherapy and immunomodulating treatment of patients with multiple myeloma].

Prospective studies were carried out on the effectiveness of various treatment methods in 208 patients with plasmocytic myeloma. In 102 patients induction therapy was based exclusively on melphalan, in 106 cases polychemotherapy was used including vincristine, melphalan, carmustine, cyclophosphamide and prednisone. The differences in the per cent of patients with good response to treatment and in the survival time after treatment beginning were statistically not significant between these groups which suggests that polychemotherapy begun from the diagnosis of the disease is justified in patients with large mass of the neoplasm and poor prognostic factors. In 45 patients chemotherapy was supported by administration of immunomodulatory agents, including calf thymus extract in 25 cases, levamisole in 18 and interferon in 2. It was observed that maintenance of remission with chemotherapy and with immunomodulatory agents calf thymus extract or levamisole prolonged the survival of the patients. In cases of leucopenia the use of calf thymus extract facilitated chemotherapy by stimulation of myelopoiesis.

Adult↗

PubMed1991

Discrepancy between biochemical normalization and morphological recovery of jejunal mucosa during postischemic reperfusion in presence of the xanthine oxidase inhibitor oxypurinol.

An increased formation of oxygen free radicals in the reperfused rat small intestine is concluded from accumulations of oxidized glutathione, of thiobarbituric acid-reactive substances and of 4-hydroxynonenal. Xanthine oxidase inhibition prevented these biochemical changes. The histological and electronmicroscopic studies of intestinal sucosa showed significant structural deteriorations already at the end of the ischemic period obviously due to disturbances of cellular energy metabolism. The extent of dosage was increased during the reperfusion without qualitative changes of the pattern of structural dosage. The beneficial effects of oxypurinol on biochemical criteria which occurred already in the early phase of reperfusion were not reflected in significant morphological differences within the first hour of reperfusion. Differences of morphological findings between oxypurinol-treated and untreated animals could be observed after longer periods of reperfusion--during the regeneration of the tissue.

Animals↗

PubMed1990

Low dose cytosine arabinoside in the treatment of the primary myelodysplastic syndrome.

23 patients with primary myelodysplastic syndrome was observed in 1982-1988. 8 patients with RAEB and RAEB-t according to FAB criterias were treated with low dose cytosine arabinoside. No complete response and only one partial response +10 months duration was achieved. Treatment had a minor influence on the natural course of disease, and doesn't protect patients from the transformation into acute leukaemias.

Adult↗

PubMed1990

[Disorders of blood platelet homeostasis in patients with multiple myeloma before the treatment and during remission].

In 28 patients with plasmocytoma selected parameters of primary haemostasis were studied before treatment and 6-9 months later, in remission. We evaluated spontaneous aggregation, aggregation induced by ADP and adrenaline, platelet factor 3 availability and the realising platelet factor 4. Significant disturbances of primary haemostasis were particularly marked in patients with a high monoclonal protein concentration (greater than 3 g/dl). During remission an increase of platelet aggregation was noted. Its values, however, remained lower than in the control group.

Adult↗

PubMed1989

Interrelationships between purine nucleotide degradation and radical formation during intestinal ischaemia and reperfusion: an application of ion-pair high-performance liquid chromatography of nucleotides, nucleosides and nucleobases.

There are peroxidative changes during the reperfusion of the rat small intestine following a 1h period of total ischaemia. That is demonstrated by the increases of the concentrations of glutathione disulphide and of thiobarbituric acid-reactive substances. An important source of the active oxygen species leading to peroxidations is the degradation of purine nucleotides. The nucleotides and their derivatives were measured by an ion-pair reversed-phase high-performance liquid chromatographic separation in a single analysis within 40 min. Modification of the elution gradient resulted in a high resolution of nucleosides and nucleobases, including allopurinol and oxypurinol. The decrease of the nucleoside triphosphate concentration and the increase of nucleoside monophosphate concentration, followed by accumulations of nucleosides and nucleobases in the course of the ischaemia were measured. During reperfusion the nucleotide pools are filled up. Restoration of adenosine triphosphate and guanosine triphosphate can be accelerated by application of the xanthine oxidoreductase inhibitor allopurinol. Pretreatment of the animals with allopurinol also diminished the formation of glutathione disulphide and thiobarbituric acid-reactive substances.

Animals↗

PubMed1989

Regulation of purine nucleotide metabolism in hypoxic liver and intestine of rats: radical scavenging effects of allopurinol and oxypurinol.

The relationship between nucleotide catabolism and generation of activated oxygen species was investigated in liver, hepatocytes and small intestine of rats. In severe hypoxia nucleotide degradation via xanthine oxidase and urate oxidase requires about half of the oxygen consumed. Data on the changes of nucleobase compounds in rat hepatocytes and small intestine during ischemia and reoxygenation and the effects of allopurinol and oxypurinol thereon are presented. From EPR measurements it is concluded that OH. radicals induce reactions of allopurinol yielding long-living products which are able to react with DMPO-OH with loss of its radical properties.

Allopurinol↗

PubMed1989

Radical formation in the rat small intestine during and following ischemia.

Oxidative loading during the reperfusion of the proximal jejunum of rats following a one hour-period of complete ischemia was demonstrated in in vivo-experiments by the increases of the GSSG: total glutathione ratio and the concentration of TBA-RS. The pretreatment of the animals with the xanthine oxidoreductase inhibitor allopurinol diminished the accumulation of GSSG and of TBA-RS. It was concluded that the purine nucleotide degradation is an important source of oxygen reduction products in reoxygenated small intestine. The tissue concentrations of nucleotides, nucleosides and nucleobases were measured by an ion-pair reversed-phase HPLC separation. There occurred fast declines of ATP and GTP concentrations during ischaemia leading to temporary increases of nucleoside mono- and diphosphate pools. The hypoxanthine concentration is increased about twentyfold during oxygen deficiency. The ATP and GTP restoration during the reperfusion was accelerated in presence of allopurinol. The shares of the beneficial allopurinol effects are not yet clarified.

Animals↗

PubMed1989

[Modified Ravitch operation in the treatment of patients with funnel chest].

The characteristic traits of funnel chest have been presented and the clinical results of surgical treatment in 13 patients by the modified Ravitch method have been discussed. Nine results were excellent and four results were good. A marked improvement of general physical function of the patients due to the increase of respiratory system efficiency and a good cosmetic effect were found. The modification of the operation consists in additional longitudinal osteotomy of the sternum, suturing of the manubrium to the sternum shaft, non-suturing of the rib cartilages after resection, filling of the through-like groove in the reposited sternum with the fragments of the resected rib cartilages, and immobilization of the fragments of the longitudinally osteotomized sternum that are inserted crosswise with several (usually three) Kirschner wires, based on the thorax.

Adolescent↗

PubMed1989

[Usefulness of Doppler echocardiography for evaluation of pulmonary hypertension based on the analysis of blood flow through the pulmonary artery].

In 41 patients with cardiac defects cardiac catheterization and echocardiographic examination were performed to evaluate the usefulness of Doppler echocardiography for estimation the grade of pulmonary hypertension. Parameter for noninvasive estimation of mean pulmonary artery pressure was the acceleration time (AcT) calculated basing on pulsed Doppler recordings of blood flow through the right ventricular outflow tract. Technics of examination and calculation of mean pulmonary artery pressure (MPAP) were concordant with Kitabatake's methodology. Patients were divided into 3 groups according to MPAP values measured by the invasive method. MPAP values obtained using Doppler method were not identical with results of direct measurements, but in the majority of patients (85%) Doppler method allowed to properly qualify patients to a respective group--with normal, moderate or very high pulmonary artery pressure. We think that the presented method is a semiquantitative one and useful for monitoring of pulmonary pressure in patients with cardiac defects.

Adult↗

PubMed1989

Large granular lymphocyte lymphocytosis with neutropenia: a case report.

A case of large granular lymphocyte lymphocytosis with neutropenia was studied as evidenced by peripheral lymphocytosis of cells having typical morphology and profound neutropenia. Surface markers analysis revealed that almost all cells were CD8+ and their subpopulation DR+. The cells had strong spontaneous and inducible suppressor functions in vitro. Moreover, their ADCC activity was strong but NK activity very weak.

Agranulocytosis↗

PubMed1989

Nucleotide degradation and radical formation in ischemic and reperfused small intestine.

Peroxidative loading during the reoxygenation of the rat small intestine following a complete ischemia was demonstrated in in vivo-experiments by the increases of the glutathione disulphide (GSSG): total glutathione ratio and the concentration of thiobarbituric acid-reactive substances (TBA-RS). The pretreatment of the rats with allopurinol diminished the accumulation of GSSG and of TBA-RS. From these effects was concluded that the purine nucleotide degradation is an important source of oxygen reduction products leading to peroxidations. The concentrations of nucleotides, nucleosides and nucleobases were measured by an ion-pair reversed-phase HPLC. The restoration of ATP and GTP concentrations during the reoxygenation period was accelerated by the application of allopurinol.

Adenine Nucleotides↗

PubMed1988