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Biomedical subjects

K Pasternak

Publications and source records attributed to K Pasternak.

At least 19 recordsLinked to original sources
PubMed2006

Changes of blood magnesium concentration in patients undergoing surgical myocardial revascularisation.

BACKGROUND: Magnesium (Mg) is the second most relevant intracellular element, which plays an important role in many physiological processes. Magnesium disorders are particularly important in haemodynamically unstable patients, such as patients after extracorporeal circulation. The aim of this study was to analyze the changes in blood Mg levels in patients undergoing coronary artery bypass procedures with extracorporeal circulation. PATIENTS AND METHODS: Twenty male patients, aged 50-69, undergoing CABG with ECC under general anaesthesia, were included in the study. All of them were operated on due to Io and IIo degree coronary disease (according to CCS). The blood concentrations of Mg were examined in five stages: 1) before the induction of anaesthesia; 2) during extracorporeal circulation; 3) after surgery; 4) in the morning of the first postoperative day; 5) in the morning of the second postoperative day. The blood Mg concentrations were determined by spectrophotometric methods. RESULTS: The blood concentration of Mg decreased during extracorporeal circulation and immediately after surgery and increased in the morning of the first and second postoperative days. CONCLUSION: The CABG with extracorporeal circulation resulted in a significant decrease in blood Mg concentration.

Aged↗
PubMed2006

The effect of preoperative magnesium supplementation on blood catecholamine concentrations in patients undergoing CABG.

BACKGROUND: It is well known that magnesium (Mg) plays an important role in many physiological processes such as regulation of blood catecholamine concentrations, particularly epinephrine (E) and norepinephrine (NE). The complex character of extracorporeal circulation (ECC) with intraoperative normovolemic haemodilution (NH) may alter blood Mg levels, which is likely to result in disorders of E and NE. The aim of this study was to analyze the influence of preoperative Mg supplementation on E and NE in patients undergoing CABG. PATIENTS AND METHODS: Forty male patients undergoing CABG under general anaesthesia were included. Patients were randomly divided into two groups: A--the patients receiving pre-operative magnesium supplementation and B--patients without pre-operative magnesium supplementation. The Mg, E and NE blood concentrations were measured in five stages: 1) before anesthesia after the radial artery cannulation, 2) during NH and ECC, 3) immediately after surgery, 4) in the morning of the 1st postoperative day, 5) in the morning of the 2nd postoperative day. The Mg levels were determined by spectrophotometric methods, E and NE were measured by radioimmunoassay methods. RESULTS: The CABG caused a decrease of Mg and an increase of E and NE in both groups, but the changes were significantly higher in group B. CONCLUSIONS: 1) CABG causes a decrease of Mg and an increase of E and NE; 2) Preoperative, oral supplementation of Mg substantially reduces intra- and postoperative disorders.

Aged↗
PubMed2005

The relationship between magnesium, epinephrine and norepinephrine blood concentrations during CABG with normovolemic hemodilution.

The effects of procedures with extracorporeal circulation on the disturbance of relationships between blood magnesium (Mg), epinephrine, and norepinephrine levels have not been explicitly explained. It is assumed that both hypomagnesemia and increased concentration of the above mentioned hormones exert adverse effects on the myocardium often causing life threatening disorders. This problem is particularly important in cases of stunned myocardium, observed after extracorporeal circulation procedures. The complex nature of the procedures and the intraoperative normovolemic hemodilution (NH) employed are likely to alter Mg, epinephrine, and norepinephrine concentrations, as well as the above mentioned relations. The aim of the study was to evaluate the changes in blood Mg, epinephrine and norepinephrine concentrations in patients undergoing extracorporeal circulation and normovolemic hemodilution. The study encompassed 16 men operated on for stable coronary disease (I or II degrees according to the Canadian Scale). The patients were divided into two groups according to body weight: A) patients weighing less than 75 kg and B) patients weighing more than 75 kg. The degree of NH caused by constant volume of priming (1800 mL) was determined on the basis of hematocrit measurements and in relation to body weight. The examinations were conducted in 5 stages: 1) after radial artery cannulation before anaesthesia and surgery, 2) during hemodilution and deepest hypothermia, 3) after surgery before sending the patient to Intensive Postoperative care Unit, 4) in the first postoperative day, 5) in the second postoperative day. The observations showed an increase in epinephrine levels in group A in the second stage and of norepinephrine levels in stage 4. Decreased blood Mg levels were noted in all the patients in the second stage, however in group A significantly lower values were also observed in stage 3. Moreover, the correlation between Mg level changes and blood epinephrine and norepinephrine levels were observed. The study revealed significant effects of extracorporeal circulation procedures on adrenergic reactions as well as blood magnesium concentrations. It seems that the degree of NH is the main factor determining blood levels of Mg, epinephrine and norepinephrine during the use of a heart-lung apparatus, which may be particularly relevant in patients with impaired heart function and low body weight.

Aged↗
PubMed2005

The degree of lymphocytic mitochondrial transmembrane potential and blood magnesium concentrations during coronary artery bypass grafting.

UNLABELLED: Magnesium (Mg) plays an important role in lymphocyte function. Low blood concentration of Mg may result in intralymphocyte imbalance and in turn may be associated with intensified apoptosis of peripheral blood lymphocytes. Due to its multistage character; extracorporeal circulation (ECC) may augment Mg disorders adding to the above mentioned pathology. The aim of this study was to assess the correlation between lymphocyte apoptosis and Mg concentration in the blood during the course of coronary artery bypass grafting (CABG) and in the early postoperative period. METHOD: Twenty male patients undergoing CABG with ECC under general anaesthesia were included in the study. For detection of apoptotic lymphocytes in the circulation, inner mitochondrial transmembrane potential (deltapsim) was measured with the use of chloromethyl-X-rosamine (CMXRos) and flow cytometry. Spectrophotometry was used for Mg blood concentration measurements. Peripheral blood samples were obtained in seven stages: 1) just before anaesthesia, 2) 2 hours after the beginning of surgery, 3) immediately after surgery, 4) 12 hours after the beginning of surgery, 5) 24 hours after the beginning of surgery, 6) 36 hours after the beginning of surgery, 7) 54 hours after the beginning of surgery. RESULTS: The statistically significant increases of lymphocyte apoptosis were noted in stages from 2 to 7. Blood Mg concentrations decreased in stages 2 and 3. There was negative correlation between Mg blood concentration in stages 2 and 3 and the intensity of lymphocyte apoptosis in the stage 5. CONCLUSIONS: 1) CABG with extracorporeal circulation was associated with a decrease of magnesium concentration in the blood and an increase of lymphocyte apoptosis intensity. 2) The decrease of magnesium blood concentration may increase the degree of lymphocyte apoptosis. 3) Lymphocyte apoptosis after extracorporeal circulation has a two-phase course.

Aged↗
PubMed2001

The changes in the antioxidant status of heart during experimental hypomagnesemia in balb/c mice.

The present experiment was performed to assess if hypomagnesemia can influence antioxidant status in mice heart. The results could explain possibly a free radical theory of heart damage in magnesium deficiency. We used a rodent model of hypomagnesemia. The magnesium sufficient group received a standard diet whereas a magnesium deficient group received the diet containing a trace amount of magnesium. The activities of the most important antioxidant enzymes--catalase, glutathione peroxidase and superoxide dismutase were assessed in mice heart and liver in a time dependent manner, on the 10th and the 20th day of experiment. The level of magnesium in plasma of animals receiving the magnesium deficient diet dropped twice after the 8th day and four times after the 13th day and then reached a plateau value. The activity of catalase in heart in the magnesium deficient group increased gradually and was significantly (P < 0.05) elevated by 27% on the 20th day of experiment whereas the superoxide dismutase activity was significantly decreased by 17% on the 20th day. Glutathione peroxidase activity was insignificantly elevated. The alterations of antioxidant enzyme activities in the heart indicate cardiomyocytes's exposure to oxidative stress, which can be responsible for the cardiac lesions observed during hypomagnesemia.

Animals↗
PubMed2000

[Trace elements in neoplasm tissues of the larynx].

Trace elements are essential for the proper functioning of the body. Changes in bioelements concentration were observed in numerous pathologic conditions. The aim of this study was evaluation of trace elements concentration in neoplasmatic tissues of the larynx. The study comprised 52 patients operated for cancer of the larynx. Levels of magnesium, zinc and copper in neoplasmatic tissues of the larynx were determined using atomic absorbtion spectrophotometry. The results were compared with the control group. Elevated levels of magnesium were observed in neoplasmatic tissues of the larynx. Zinc and copper levels were lowered in comparison with the control group. The results were statistically analysed.

Adult↗
PubMed1999

Immunomodulatory effect of selenosemicarbazides and selenium inorganic compounds, distribution in organs after selenium supplementation.

Antioxidant properties of selenium producing a protective barrier against free radicals play an important role in numerous metabolic and immunologic processes associated with oxidation-reduction reactions which take place during intracellular digestion of phagocyted bacteria. The aim of our study was to examine the properties of an organic compound of selenium, 4-(o-tolilo)-selenosemicarbazide of p-chlorobenzoic acid in terms of its retention in organs, effect on erythropoesis and phagocytic abilities of neutrophiles as well as antioxidant properties in neutrophiles tested with NBT test. This compound as well as inorganic sodium selenate was given to Swiss mice at the dose of 10(-3) g Se/kg for the period of 10 days. The concentrations of selenium in livers of mice treated with sodium selenate and selenosemicarbazide were found to be higher than in controls (18.7 micrograms lg-1 and 23.2 micrograms lg-1 vs. 12 micrograms lg-1, respectively). Analysis of blood cells count has shown a significant decrease in neutrophile levels in both groups treated with selenium. The influence of selenium compounds on phagocytosis and especially NBT test has been determined (3.8% of positive cells in the controls vs. 2.2% and 0.9% in the groups treated with sodium selenate and selenosemicarbazide, respectively). Our preliminary investigations suggest that selenosemicarbazides are biologically active compounds and can modify neutrophile functions.

Animals↗
PubMed1999

[Magnesium and zinc levels in blood serum and cerebrospinal fluid in children with febrile convulsions].

Magnesium and zinc levels in blood serum and cerebrospinal fluid were estimated in 18 children aged 8 months-5 years with febrile convulsions. Control group consisted of 15 apparently healthy children in the same age. On the ground of ethical reasons no control values for cerebrospinal fluid were evaluated. The mean serum concentration of magnesium and zinc was significantly lower in the sick children (p < 0.001 and p < 0.05 resp.). The magnesium levels in cerebrospinal fluid were evidently lower than those quoted in the literature and the mean concentration of zinc was higher in comparison with literature data. The presumable pathogenetic role of disturbed magnesium and zinc metabolism in febrile convulsions is discussed.

Child, Preschool↗
PubMed1999

Magnesium in stomach cancer.

Experiments were conducted in order to determine magnesium concentrations in stomach cancer tissue. As a control, non-cancerous stomach tissue of the same patients was used. Mg concentration in blood serum was also tested in all patients undergoing surgical operation. It has been determined that Mg concentration was higher in cancerous stomach tissue than in control tissue. Average Mg concentration in the blood serum of patients with stomach cancer fluctuates near the lower limit of normal. An analysis of the relationship between Mg concentration and the degree of clinical advancement of cancer has shown that Mg concentration in cancerous stomach tissue increases with the clinical stage. The results obtained were statistically significant. They show that there is a relationship between Mg concentration and the development of stomach cancer.

Gastric Mucosa↗
PubMed1999

Tissue concentrations of magnesium in rats receiving various dosages of ethanol.

Ethanol exerts various influences on living organisms. The experiments were conducted in order to determine the influence of ethanol on changes of magnesium concentration in various tissues. The experiment was conducted on white Wistar rats of both sexes. The animals were divided into groups of ten rats each. They received ethanol in their drinking water for 6 weeks. The first group received 5 per cent ethanol, the second received 20 per cent ethanol, the third was the control group and received water. All animals were fed with the same laboratory feed and watered ad libitum. After the duration of the experiment the animals were sacrificed using ketamine. The brain, liver, heart, lung, kidney, spleen, femoral muscle and blood serum were then harvested for further testing. The magnesium concentration was tested in these tissues by using atomic absorption spectrophotometry (AAS). Ethanol in feed causes a shift in the tissue concentration of magnesium. The range of these concentration differences is determined by the dosages as well as by the type of tissue.

Administration, Oral↗
PubMed1999

The influence of ethanol and magnesium on aminoacyl-tRNA synthetases activity in rat's liver.

Ethanol exerts various influences on living organisms. Experiments were conducted in order to determine the influence of ethanol and magnesium on the aminoacyl-tRNA synthetases (aaRS) activity in rat's liver. The experiment was conducted on white Wistar rats of both sexes. The animals were divided into groups of 10 rats each. They received ethanol in their drinking water for 6 weeks. The first group received 5 per cent ethanol, the second received 20 per cent ethanol, the third received 20 per cent ethanol and 200 ppm magnesium, the fourth was the control and received water. After the duration of the experiments the animals were sacrificed using ketamine and the livers were harvested for further testing. Aminoacyl-tRNA synthetases were obtained by salting out with ammonium sulphate. The aminoacyl-tRNA synthetases activity were tested in vitro by using marked amino acids. Ethanol influences aminoacyl-tRNA synthetases activity. The influence of ethanol on the activity of aaRS depended on the size of the dose of ethanol taken by examined animals. At the same time it was revealed that magnesium supplementation limits the negative effect of high ethanol doses.

Administration, Oral↗
PubMed1998

The effect of a single dose of morphine and ethanol on magnesium level in blood serum and tissues in mice.

The effect of a single dose of morphine (50 mg/kg) and ethanol (2 g/kg) on total magnesium content in blood serum, brain, heart, lung, kidney, liver, femoral muscle and spleen in mice was studied. Significant decrease of magnesium serum concentration was observed after morphine and ethanol administration but not after both drugs given simultaneously. Morphine caused the evident decrease of magnesium content in brain, lung, kidney and muscle, while it was elevated in heart and spleen and unchanged in liver. Ethanol produced significant decrease of magnesium content in heart, lung and kidney and it's increase in liver and spleen. Concomitant administration of both drugs was connected with the diminished amount of magnesium in heart, lung, kidney and muscle and led to the rising of magnesium content in spleen. It is concluded that even a single dose of investigated drugs is sufficient to produce promptly some risk of alterations in magnesium homeostasis.

Animals↗
PubMed1997

The effectiveness of the bonding of amino acid by tRNA of livers of rats experimentally exposed to cadmium and barium.

The process of amino acid activation takes place in the presence of specific aminoacyl-tRNA synthetases. These enzymes, together with ATP, catalyse the bonding of tRNA and amino acids (5). The effectiveness of binding amino acid by tRNA has a direct influence on the intensity of protein biosynthesis. This effectiveness varies in various metabolic states of the cell (16). Heavy metals influence cellular metabolism. They usually reduce enzyme activity, block chemical reactions, bind with proteins, interact with other elements and even break certain bonds (1, 8, 9, 11, 14). Experiments in the present work were conducted in order to determine changes in the effectiveness of amino acid binding by tRNA of the livers of rats receiving heavy metals such as cadmium and barium in their feed.

Adenosine Triphosphate↗
PubMed1997

[Activity of isocitrate dehydrogenase in breast cancer].

The activity of isocitrate dehydrogenase (ICDH) was studied in the tissue of breast cancer and in the blood serum of the women suffering from this neoplasm. The comparative material was the physiological tissue of mammae and blood serum of the healthy women. The activity of ICDH in neoplasm tissue was more higher than in physiological tissue. In the blood serum of ill patients activity of this enzyme was higher than in control serums too.

Breast Neoplasms↗