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J Zawadzki

Publications and source records attributed to J Zawadzki.

At least 19 recordsLinked to original sources
PubMed2006

Using of high-resolution topsoil magnetic screening for assessment of dust deposition: comparison of forest and arable soil datasets.

Magnetic susceptibility (kappa) is an easily detectable geophysical parameter that can be used as a proxy or semi-quantitative tracer of atmospheric industrial and urban dusts deposited in topsoil. An enhanced kappa value of topsoil is in many cases also associated with high concentrations of soil pollutants (mostly heavy metals). High-resolution magnetic screening of topsoil in areas of high pollution influx is a useful tool for detection of pollution "hot spots". General and regional screening maps with a grid density of 10 or 5 km have been performed on the basis of forest topsoil measurement only. The purpose of this study was to perform high-resolution magnetic screening with different grid densities in both forested and agricultural areas (arable land). Our large study area (ca. 200 km(2)) was located in a relatively more polluted region of the central part of Upper Silesia, and a second (small) one (ca. 100 m(2)) was located in the western part of Upper Silesia, with considerably lower influx of pollution. In the framework of this study, we applied a statistical comparison of data obtained in forested areas and on arable land. The arable soil showed statistically significantly lower kappa values, the result of "physical dilution" of the arable layer caused by annual ploughing. Thus arable soils must be avoided during high-resolution field measurement. From semivariograms, it was clear that the spatial correlations in forest topsoil are much stronger than in arable soil, which suggests that a denser measurement grid is required in forested areas.

Dust↗
PubMed1998

The glycoinositolphospholipids from Leishmania panamensis contain unusual glycan and lipid moieties.

The cell surface of Leishmania parasites is coated by glycosylphosphatidylinositol (GPI)-anchored macromolecules (glycoproteins and a lipophosphoglycan) and a polymorphic family of free GPI glycolipids or glycoinositolphospholipids (GIPLs). Here we show that GIPLs with unusual glycan and lipid moieties are likely to be major cell surface components of L. panamensis (subgenus Viannia) promastigotes. These glycolipids were purified by high performance thin layer chromatography and their structures determined by gas-liquid chromatography-mass spectrometry, fast-atom bombardment mass spectrometry, methylation analysis and chemical and enzymatic sequencing of the glycan headgroups. The major GIPLs contained two glycan core sequences, Manalpha1-3Manalpha1-4GlcN-phosphatidylinositol (type-2 series) or Manalpha1-3[Manalpha1-2Manalpha1-6]Manalpha1- 4GlcN-phosphatidylinosit ol (hybrid series), which were elaborated with Galalpha1-2Galbeta1- or Galalpha1-2/3Galalpha1-2Galbeta1- extensions that were attached to the 3-position of the alpha1-3 linked mannose. The phosphatidylinositol moiety contained exclusively diacylglycerol with palmitoyl, stearoyl and heptadecanoyl chains. Non-galactosylated GIPL species with the same core structures were also found. The galactose extensions and the presence of diacylglycerol in the lipid moieties are novel features for the GIPLs of Leishmania spp. The implications of these structures for the biosynthesis of leishmanial GIPLs and their putative function in the mammalian host are discussed.

Animals↗
PubMed1998

Permeability defect with bicarbonate leak as a mechanism of immune-related distal renal tubular acidosis.

We present a 15-year-old girl with distal renal tubular acidosis (dRTA) appearing in what is probably a very early stage of primary Sjögren's syndrome. On the basis of tests evaluating renal handling of H+, we attempt to explain the mechanism of the urine acidification disorder. The inability to decrease urinary pH during systemic acidosis, together with the normal increase of urinary carbon dioxide partial pressure (pCO2) values after sodium bicarbonate and neutral phosphate loading, suggest a gradient-type dRTA. The inability to lower urinary pH in response to furosemide, accompanied by markedly increased urinary excretion of NH4, HCO3, Na, and K, points to a collecting tubule permeability disorder with bicarbonate leak to the tubular lumen. This patient had never been exposed to amphotericin B. To our knowledge, immune-related dRTA as a result of a gradient defect with bicarbonate leak into the tubular lumen has not been described.

Acidosis, Renal Tubular↗
PubMed1997

Mechanism of hypouricemia in a child with the normotensive form of Gordon's syndrome.

The mechanism of renal tubular urate transport disorder was studied by the pyrazinamide and probenecid tests in a 12-year-old hypouricemic boy suffering from the normotensive form of Gordon's syndrome, with increased distal tubular reabsorption of NaCl (confirmed by the hypotonic saline diuresis test). The aim of the study was to determine the impact of oral hydration during the tests on the phases of renal tubular urate transport: before (I), and during long-term hydrochlorothiazide therapy (0.5 mg/kg BW/day) (II). In both periods (I,II), presecretory reabsorption of urate was within normal limits. Hypouricemia in our patient was caused by decreased postsecretory reabsorption, with or without simultaneous increase of tubular urate secretion. The degree of overhydration determines which of these mechanisms is responsible for increased renal urate clearance.

Blood Pressure↗
PubMed1996

Disorders of magnesium homeostasis in the course of liver disease in children.

Magnesium deficiency can develop in patients with acute or chronic liver disease as a result of low dietary magnesium intake, low intestinal absorption or renal magnesium loss caused by natriuretic drugs. The aim of this study was to evaluate magnesium homeostasis in 39 children: 10 with acute liver failure due to Amanita phalloides poisoning. 14 with chronic liver diseases without cholestasis, and 15 with chronic liver diseases with cholestasis. Serum magnesium and fractional and 24 h urinary magnesium excretion were measured in all the children. Magnesium retention after intravenous infusion was also evaluated. Tissue magnesium deficit was found in 30 per cent of children with acute or chronic liver disease.

Adolescent↗
PubMed1996

[Uric acid metabolism abnormalities in IgA nephropathies].

The possibility of uric acid tract stones forming was analysed in 12 children with IgA nephropathy (group I) and 10 children with other hematuric glomerulopathies (group II). Elevated serum uric acid level and higher urinary excretion was found only in children with IgAN during exacerbation of the disease. Uric acid nephrolithiasis was found only in children with IgA nephropathy. The prophylactic treatment (proper diet, high fluid intake, adjusting urinary pH to 6.5-6.8) was effective in decreasing the number of exacerbations, urinary tract infections and formation of uric acid stones.

Abdominal Pain↗
PubMed1995

Effect of nifedipine on tubular handling of uric acid in transplanted kidney on cyclosporine A treatment.

Hyperuricemia resulting from tubular urate transport defects is a well-known nephrotoxic effect of cyclosporine A (CyA) on renal blood perfusion in organ recipients. The aim of this study was to define the mechanism of the tubular urate transport defect in hyperuricemic renal graft recipients on CyA and to evaluate the effect of nifedipine retard administration on this tubular dysfunction. Tubular uric acid transport was evaluated by the probenecid test in 17 hyperuricemic (group 1) and 6 normouricemic (group 2) renal graft recipients treated with CyA. Maximal urate excretion after probenecid administration was 25.5 +/- 4.6 versus 42.5 +/- 7.7% (p < 0.001) and postsecretory urate reabsorption was 79.2 +/- 8.3 versus 78.5 +/- 9.7% (NS), respectively. The effects of nifedipine retard on renal urate transport were evaluated in 6 hyperuricemic patients. Seven days of nifedipine therapy did not significantly decrease mean serum uric acid levels (7.7 +/- 1.6 to 7.1 +/- 1.1 mg/dl) nor increase urate clearance (3.8 +/- 1.3 to 4.7 +/- 1.6 ml/min/1.73 m2). The uricosuric effect of probenecid was manifested by an increase in tubular urate transport from 25.5 +/- 4.6 to 37.3 +/- 7.2%, p < 0.01, paralleled by an increase in postsecretory urate reabsorption from 20.5 +/- 3.7 to 31.4 +/- 5.7% (p < 0.003). Postsecretory reabsorption expressed as a percentage of secreted urate in both evaluations did not differ significantly (80.3 +/- 6.2 vs. 84.4 +/- 3.1%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Long-term repopulating abilities of enriched fetal liver stem cells measured by competitive repopulation.

To characterize hematopoietic cell biology, many investigators have used protocols that enrich for primitive hematopoietic stem cells (PHSC). In this study, we quantified the long-term repopulating ability (LTRA) of enriched and discarded fractions of PHSC from day-14 murine fetal liver using the competitive repopulation assay. We fractionated populations of fetal cells using the antigenic markers AA4.1+, AA4.1+/Sca+, and AA4.1+/Linlow/Sca+. Differentiating and repopulating abilities of each of these populations were directly compared using competitive repopulation. Adult bone marrow was mixed with fetal cell fractions from congenic donors having genetically distinguishable markers, and mixtures were given to irradiated recipients. Differentiating and repopulating abilities of the enriched donor cells were measured by the proportions of myeloid and lymphoid cells having donor markers that repopulated the recipients. LTRA was found primarily in the AA4.1+ and AA4.1+/Sca+ subpopulations. Further fractionation of the AA4.1+ cells to derive an AA4.1+/Linlow/Sca+ fraction showed that virtually all of the long-term stem cell activity was found in this subpopulation. These cells were 1400- to 1600-fold enriched in long-term functional ability compared to fresh marrow. This very high multilineage repopulating ability per cell was directly measured using a long-term functional assay in vivo. Importantly, the measured repopulating ability for AA4.1+/Linlow/Sca+ cells was about five-fold less than expected from the fraction of cells enriched and remained two- to three-fold less even after compensating for repopulating ability in discarded fractions. This illustrates that long-term functional abilities of enriched PHSC cannot be estimated from fractions enriched but should be quantitatively assayed.

Aging↗
PubMed1993

Hypouricemia due to increased tubular secretion of urate in children with Amanita phalloides poisoning.

The tubular transport of urate was studied in 20 children poisoned with Amanita phalloides and in control group. The aim of this study was to investigate the cause of repeatedly observed episodes of hypouricemia in patients after A. phalloides poisoning. A significant negative correlation between serum uric acid concentration and fractional excretion of urate in poisoned and control groups (r = 0.73, p < 0.001) was found. The results of pyrazinamide and probenecid tests performed in patients after A. phalloides poisoning indicated that hyperuricosuria was most likely due to an increment in renal tubular urate secretion, and not due to decreased presecretory and postsecretory reabsorption of uric acid. These findings indicate that hypouricemia found after A. phalloides poisoning in children is of renal origin due to an increase in tubular urate secretion.

Adolescent↗
PubMed1991

Abnormal desolvation behavior on solvate of etodolac sodium salt.

Sodium salts of (+/-)- and (+)-etodolac were prepared and characterized: the (+/-)-sodium salt contained 5.26% water and 1.09% acetonitrile, and the (+)-sodium salt contained 1.14% water and 2.02% other volatiles (methanol and acetonitrile). Abnormal hygroscopic behavior of the (+/-)-etodolac sodium salt was observed; that is, it lost weight (5.4%) at 75% RH for 7 days. A possible reason for the abnormal hygroscopic behavior is nucleation phenomenon at the interface; that is, a surface change may occur in the presence of water vapor with nucleation by small crystals of the product.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1991

Whitening of brown-shelled eggs: mineral composition of uterine fluid and rate of protoporphyrin deposition.

Changes in the mineral composition of uterine fluid during shell formation and the rates of color appearance and porphyrin deposition on the shell were measured in two subpopulations of brown egg-laying hens with familial histories of low or high incidences of shell whitening. Increases in shell weight and shell breaking strength were correlated with, and proportional to, time spent by the egg in the uterus and were similar in both subpopulations. Shell reflectance decreased and the amount of porphyrin deposited increased linearly 20 to 24 h after oviposition of the preceding egg. Porphyrin deposition was slightly higher at the 23-h stage in the high whitening population but similar amounts of porphyrin were deposited on the shell during the final stage of shell formation in both groups. The coating on the shell responsible for whitening was deposited during the hour prior to oviposition. Uterine fluid pH, pCO2, bicarbonate, and ionized Ca concentrations changed during shell formation but these changes were not related to the incidence of whitening. A milieu supersaturated with calcite solubility product was observed whatever the stage of shell formation. Inorganic phosphorus was not detectable in the uterine fluid whatever the stage of shell formation. The soluble phosphorus fraction of uterine decreased 22 h after oviposition and phosphorus deposition on the shell increased. At the end of egg formation uterine fluid could not be collected. It was concluded that shell whitening was associated with changes in the kinetics of porphyrin deposition rather than with changes in the amount of porphyrin deposited or modifications of uterine fluid composition.

Animals↗
PubMed1988

Procoagulant activity of gastric, colorectal, and renal cancer is factor VII-dependent.

The PA of GC, CC, and RC extracts was assayed by the recalcification of human normal or F VII-DP, and the PA of normal tissue was also determined. The PA of normal tissue was higher than that of the cancer tissues in all groups of specimens. Substitution of normal plasma by F VII-DP resulted in significant depression of the PA and the differences in the PA between the normal and cancer tissue samples disappeared. Preincubation of normal and cancer tissue extracts with the cysteine proteinase inhibitors, mercuric chloride and iodoacetamide, did not affect the PA of these extracts. We conclude that the PA of the investigated cancer extracts is factor VII-dependent and can be related to the presence of tissue factor within cancer tissue.

Blood Coagulation Factors↗