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K Bieniek

Publications and source records attributed to K Bieniek.

10 recordsLinked to original sources
PubMed1998

Tumor necrosis factor and interferon activity in the circulation of calves after repeated injection of low doses of lipopolysaccharide.

The effect of two intravenous (i.v.) injections of low doses of lipopolysaccharide (LPS)(0.1 microgram/kg of body weight) administered at 7-day intervals on the systemic release of tumor necrosis factor (TNF) and interferon (IFN), on the rectal temperature, breathing and heart rate, and on packed cell volume (PCV), plasma glucose concentration, white blood cell (WBC) counts in 3-week-old calves, was estimated. The first injection of LPS caused a significant increase in breathing and heart rate, rectal temperature, prolonged hypoglycemia and leukopenia, but no significant changes in PCV were observed. TNF and IFN activity peaked at 2 h after LPS injection and disappeared from circulation by 4 h and 5 h, respectively. After the second injection of LPS, the reaction of calves was similar to that observed after the first injection, however, the breathing rate and TNF systemic production were significantly reduced. The results obtained indicate that a low dose of LPS leads to the development of 'late' tolerance manifested by hyporeactivity to TNF production but with maintained responsivity to IFN production, pyrogenic, hypoglycemic and leukemic response to the second injection of LPS. In conclusion, these results demonstrate that the tolerance response is not universal to all hematologic and immunologic parameters, and that the response needs to be evaluated with respect to the specific variable.

Animals↗
PubMed1998

Interferon and tumor necrosis factor production during endotoxemia in sheep.

In humans endotoxemia has often been associated with the development of adult respiratory distress syndrome (ARDS). Sheep have an abundant population of pulmonary intravascular macrophages, therefore they are a popular animal model for ARDS. In this study we characterized the temporal sequence and duration of the release of two cytokines: tumor necrosis factor (TNF) and interferon (IFN) and evaluated the effect of lipopolysaccharide (LPS) dose. Rectal temperature and white blood cell (WBC) count were also measured. Twenty four adult sheep were given E. coli endotoxin at a dose of 0 (saline solution) 0.05, 0.1 and 1.0 microg/kg of body weight by intravenous (i.v.) bolus. In all groups, TNF-alpha was produced earlier (3-4.5 h) after injection than IFN (4-5 h). No correlation between increased rectal temperature, the magnitude of leukopenia and time course of both cytokines production was observed. No straight relationship between LPS dose and the titer of cytokines was seen, but lower doses of LPS-induced delayed cytokine response in comparison to the dose 1 microg/kg of LPS. As IFN, present in the circulation of sheep, was mainly alpha/beta type, the role of this class of IFN in endotoxemia is discussed.

Animals↗
PubMed1998

Effect of duodenal glucose infusion on blood glucose concentration in endotoxin-treated calves.

The effect of endotoxemia on the intestinal absorption of glucose was evaluated in nine experiments performed on seven 3- to 5-week-old calves fitted with a duodenal cannula. An intraduodenal glucose load trial (infusion of 2 g glucose/kg b.w. as a 10% aqueous solution through the cannula over 60 min) was conducted in a group of 5 calves three times during the 4-day period: 48 h before and at 2 and 24 h after i.v. injection of E. coli 0111:B4 endotoxin (LPS) at a dose of 0.1 microgram/kg b.w. Control calves were treated similarly but instead of glucose they were infused intraduodenally with deionised water at a volume of 20 ml/kg b.w. In trial with glucose load performed 48 h before LPS administration, blood glucose concentration increased during the absorptive phase from 4.32 +/- 0.32 mmol/l to 11.45 +/- 0.87 mmol/l at 60 min and then decreased to a minimum value of 3.16 +/- 0.51 mmol/l at 240 min. During the initial phase of endotoxemia, blood glucose concentration did not change from baseline values in both groups of calves. Glucose concentration in control calves started to decrease at 165 min reaching a minimum value of 1.39 +/- 0.17 mmol/l at 210 min and then increased to 2.44 +/- 0.11 mmol/l at 480 min after LPS administration. The intraduodenal infusion of glucose at 2 h after LPS administration resulted in an increase in blood glucose concentration during the absorptive phase only in one calf. Blood glucose concentration in this calf increased between 30 and 90 min reaching a maximum value of 7.19 mmol/l at 60 min, and then decreased to a minimal value of 0.94 mmol/l at 180 min after glucose load. In the remaining four calves in this group, blood glucose concentration ranged from 3.89 +/- 0.37 mmol/l to 4.48 +/- 0.45 mmol/l up to 120 min, and then steadily decreased to a minimal value of 2.41 +/- 0.41 mmol/l at 300 min. In trial with glucose load performed 24 h after LPS administration, the rate of entry of glucose into the circulation during the absorptive phase was similar to that observed in the trial performed 48 h before LPS administration. In conclusion, these results indicate that endotoxemia impairs the intestinal absorption of glucose in calves. The magnitude of the absorption disturbance may vary in individual calves, and the inhibitory effect of LPS on the intestinal glucose absorption lasts less than 24 h.

Animals↗
PubMed1991

[System for intraoral repair of ceramic blends--an in vitro study of adhesive strength].

We investigated composite repair systems for crown facings which consisted in principle of a silane primer, of an unfilled Bis-GMA bonding agent and of a filled Bis-GMA resin. The in vitro investigations revealed that under oral conditions the longterm durability of the bond strength is still unsufficient, unless care is taken that the debris layer which is caused by mechanical treatment has been removed.

Adhesiveness↗
PubMed1989

[Comparative studies on different full and veneer-ceramic crowns].

Under quasi-clinical conditions, Dicor, Hi-Ceram, Ceraplatin and PFM (porcelain butt margin) crowns with ceramic shoulders manufactured by commercial laboratories for the same metal master die were examined for marginal defects under the electron microscope. With equal cementing conditions and points of measurement for all crowns, the PFM crowns were found to be significantly superior to the other crown types. However, this result becomes relativistic in view of the great statistical variances involved.

Crowns↗
PubMed1986

[Acid-base equilibrium in experimental acid indigestion in cattle].

Blood and urine acid-base parameters were investigated in 4 heifers with acid indigestion produced by intraruminal infusion of sugar in a dose of 12 g/kg b.wt. Observations were carried out for 9 days after sugar administration. It was found that rumen acidosis was accompanied by disturbances in blood acid-base balance characteristic of partially compensated metabolic acidosis. The most pronounced changes in acid-base parameters were observed within the first 24 hours after sugar infusion, i.e. during rapid increase of lactic acid levels in blood. These changes were reflected by a decrease of blood pH values to 7.138-7.275 reduction in standard bicarbonate to 12.2-17.0 mmol/l and deficiency in base excess ranging from 9.3 to 16.7 mmol/l. The maximum reduction in partial pressure of CO2 to 4.35-4.79 kPa occurred during the second day of the experiment. The duration of acid-base disturbances depended on their intensity in individual animals and oscillated between 4 and 9 days after sugar administration. When acidosis subsided, acid-base balance returned to normal or showed a tendency toward blood alkalization. The observed decrease of pH values in urine to 5.42-5.74 and renal acid excretion from 170 to 299 mmol/l indicate a significant role of kidney function in the correction of metabolic acidosis.

Acid-Base Equilibrium↗
PubMed1981

[Liver function in cattle in experimental rumen acidosis].

The investigations were performed on 6 Friesian-Holstein heifers, weighing 410-504 kg, in which acid indigestion was induced by intraruminal administration of saccharose in a dose of 12 g/kg body weight. The animals were observed for 9 days after the treatment. Functional state of the liver was evaluated on the basis of bromosulphthalein clearance, total bilirubin level and aspartate amino-transferase (AspAT) activity in serum, concentration of blood glucose, total serum protein and protein fractions. Within the first 24 hours, all heifers developed acute symptoms of rumen acidosis which persisted for 3 days after saccharose administration. Afterwards, a phase of gradual spontaneous recovery was observed. In the course of rumen acidosis a reduction in bromosulphthalein clearance, an increase in bilirubin level and AspAT activity, a decrease and then an increase in glucose concentration and a reduction in albumin content and, as a consequence, in albumin/globulin ratio were found. The results indicate that experimental rumen acidosis produced disturbances in excretory and metabolic functions of the liver in the examined heifers. Changes in biochemical parameters were preceded by an increase in AspAT activity and were most remarkable between 48 and 144 hours after saccharose administration. Liver dysfunction was of a various degree in individual animals and recovered within a relatively short period following the disappearance of rumen acidosis symptoms.

Acidosis↗