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Biomedical subjects

J Nowak

Publications and source records attributed to J Nowak.

At least 91 records · Page 5Linked to original sources
PubMed1994

Insulin and sugar concentration changes in mammary secretion in sheep during the periparturient period.

The radioimmunoassayable concentration of insulin in isolated whey fractions of mammary secretion of sheep (n = 28) was measured. The concentrations were high on the last 2 days of pregnancy (550 +/- 80 and 580 +/- 77 microU/ml, respectively), higher on the day of parturition (780 +/- 71 microU/ml) and lower on the next day (290 +/- 54 microU/ml). During the following 4 consecutive days the concentrations gradually decreased to an almost basal blood level (14 microU/ml). The high insulin concentration in the mammary secretion during the periparturient period might be the result of intensified transfer of insulin through the blood-mammary barrier and increasing needs for this hormone by developing mammocytes and probably for the newborn lambs (n = 42) adapting to extra-uterine life. Conversely to the consecutive decrease in insulin, progressively increasing concentrations of sugars in mammary secretions were observed (from 2.1 +/- 0.22% on the second day prior to parturition to 5.5 +/- 0.13% on the fifth day post partum.

Animals↗
PubMed1994

Increased urinary excretion of a major thromboxane metabolite in early alcohol withdrawal.

Urinary excretion of 2,3-dinor-thromboxane B2 as a marker of in vivo thromboxane A2 (TxA2) biosynthesis was measured in six alcoholics 1 and 14 days after the cessation of heavy drinking using gas chromatography/mass spectrometry. Six non-alcoholic healthy volunteers served as controls. One day after alcohol withdrawal the excretion of the dinor metabolite was significantly higher (P < 0.01) in the alcoholics (408 +/- 42 pg mg-1 creatinine) than in the controls (180 +/- 30 pg mg-1 creatinine) and was accompanied by a significantly reduced platelet count (103.0 +/- 20.2 x 10(9) l-1 vs. 194.0 +/- 13.9 x 10(9) l-1 in controls; P < 0.01). The metabolite excretion fell then significantly (P < 0.05) to 245 +/- 53 pg mg-1 creatinine 14 days after alcohol withdrawal and this was paralleled by an increase in platelet count to 453.5 +/- 72.0 x 10(9) l-1 (P < 0.05). The present results support the hypothesis that Tx-A2 biosynthesis is increased in early alcohol withdrawal and strongly suggest platelets as a cellular origin of the increased TxA2 formation.

Adult↗
PubMed1994

Reduced expression of erythrocyte complement receptor (C3bR) in MS.

The study was carried out in patients with MS (n-121) and in control group (n-519). On the basis of haemagglutination intensity and results of radioimmunoassay three phenotypes of complement receptor were classified: high HH, medium HL, and low LL. Considerable differences were observed in the distribution of these phenotypes between controls and MS in whom the low phenotype was more frequent. Family studies suggest that reduced expression of the complement receptor on the erythrocytes depends in MS on the disease process in the first place, and not on genetic factors.

Erythrocytes↗
PubMed1994

Pharmacological characterization of a biosynthetic trisulfide-containing hydrophobic derivative of human growth hormone: comparison with standard 22 K growth hormone.

Growth hormone is the classical anabolic hormone which promotes organ growth after binding to somatogenic target cell receptors, present in various target tissues. The present study elucidated the pharmacological characteristics in vitro and in vivo of human growth hormone and a recently identified by-product of a recombinant human growth hormone preparation; i.e. a trisulfide-containing (cys 182-cys 189) hydrophobic, folding derivative of growth hormone, hydrophobic derivative-growth hormone. Standard growth hormone and hydrophobic derivative-growth hormone possessed similar characteristics in vitro, both as regards binding to the somatogenic receptor on the human IM-9 cell line, and the prolactin receptor-mediated proliferation of rat Nb2 cells. This indicates that no change occurs in the binding characteristics in spite of a change in conformation of the molecule. Using an ELISA assay that detected standard and hydrophobic derivative-growth hormone equally well, the plasma pharmacokinetical profiles of the preparations following a single intravenous or subcutaneous dose were indistinguishable. Thus, following initial disposition of hydrophobic derivative-growth hormone and standard growth hormone into a volume, V1, of one to two times the plasma volume, almost 90% of either compound disappeared from plasma during the alpha-phase of the plasma decay curve. Similar half-lives of 4-5 min. were found for hydrophobic derivative-growth hormone and standard growth hormone during this phase, indicating rapid removal of drug from the circulation. Also, the AUC and Cmax values for standard and hydrophobic derivative-growth hormone did not differ following intravenous or subcutaneous administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Rearrangement of T-cell receptor delta/gamma genes: application to the study of clonality in childhood B-lineage acute lymphoblastic leukaemia.

DNA-based PCR with various sets of primers for T-cell receptor gamma/delta (TCR gamma/delta) chain genes was used to study clonality in childhood B-lineage acute lymphoblastic leukaemia. TCR delta genes rearrangements were the most common and were observed in 77 patients (64.2%). The typical pattern of rearrangements was defined as an incomplete V delta 2 to D delta 3 or to D delta 2 recombination product. Rearrangements of TCR gamma genes were observed in 61 cases (50.8%). Predominantly, TCR gamma genes rearrangements were detected in null-ALL and the early B-ALL (55.2% and 60%, respectively) and were rather rare in other groups. From all eight V segments of V gamma l group rearrangements concerned mostly regions V gamma 2, V gamma 4 and V gamma 7. We have confirmed that TCR gamma and delta genes amplification provides a rapid, sensitive method for assessing clonality in ALL almost in 100%.

Adolescent↗
PubMed1993

A twin study of genetic and environmental contributions to liability for posttraumatic stress symptoms.

We studied 4042 Vietnam era veteran monozygotic and dizygotic male twin pairs to determine the effects of heredity, shared environment, and unique environment on the liability for 15 self-reported posttraumatic stress disorder symptoms included in the symptom categories of reexperiencing the trauma, avoidance of stimuli related to the trauma, and increased arousal. Quantitative genetic analysis reveals that inheritance has a substantial influence on liability for all symptoms. Symptoms in the reexperiencing cluster and one symptom in the avoidance and numbing cluster are strongly associated with combat exposure, and monozygotic pairs are more highly concordant for combat exposure than dizygotic pairs. By fitting a bivariate genetic model, we show that there are significant genetic influences on symptom liability, even after adjusting for differences in combat exposure; genetic factors account for 13% to 30% of the variance in liability for symptoms in the reexperiencing cluster, 30% to 34% for symptoms in the avoidance cluster, and 28% to 32% for symptoms in the arousal cluster. There is no evidence that shared environment contributes to the development of posttraumatic stress disorder symptoms.

Asia, Southeastern↗
PubMed1993

Electrocardiogram signal variance analysis in the diagnosis of coronary artery disease--a comparison with exercise stress test in an angiographically documented high prevalence population.

Variance electrocardiography (variance ECG) is a new resting procedure for detection of coronary artery disease (CAD). The method measures variability in the electrical expression of the depolarization phase induced by this disease. The time-domain analysis is performed on 220 cardiac cycles using high-fidelity ECG signals from 24 leads, and the phase-locked temporal electrical heterogeneity is expressed as a nondimensional CAD index (CAD-I) with the values of 0-150. This study compares the diagnostic efficiency of variance ECG and exercise stress test in a high prevalence population. A total of 199 symptomatic patients evaluated with coronary angiography was subjected to variance ECG and exercise test on a bicycle ergometer as a continuous ramp. The discriminant accuracy of the two methods was assessed employing the receiver operating characteristic curves constructed by successive consideration of several CAD-I cutpoint values and various threshold criteria based on ST-segment depression exclusively or in combination with exertional chest pain. Of these patients, 175 with CAD (> or = 50% luminal stenosis in 1 + major epicardial arteries) presented a mean CAD-I of 88 +/- 22, compared with 70 +/- 21 in 24 nonaffected patients (p < 0.01). Variance ECG provided a stochastically significant discrimination (p < 0.01) which was matched by exercise test only when chest pain variable was added to ST-segment depression as a discriminating criterion. Even then, the exercise test diagnosed single-vessel disease with a significantly lower sensitivity. At a cutpoint of CAD-I > or = 70, compared with ST-segment depression > or = 1 mm combined with exertional chest pain, the overall sensitivity of variance ECG was significantly higher (p < 0.01) than that of exercise test (79 vs. 48%). When combined, the two methods identified 93% of coronary angiography positive cases. Variance ECG is an efficient diagnostic method which compares favorably with exercise test for detection of CAD in high prevalence population.

Adult↗
PubMed1993

Analysis of organic vapors in the workplace by remote sensing Fourier transform infrared spectroscopy.

A Remote Sensing-Fourier Transform Infrared (RS-FTIR) system was applied to identify and quantify air contaminants along the beam, ranging from single compounds to mixtures, in various workplaces. Gas chromatography (GC) was used to provide information of point concentration variation by means of analyzing charcoal tube samples placed along the beam path. The results indicated a correlation between the charcoal tube-GC and the RS-FTIR for the analysis of most compounds. Discrepancies were found for some compounds, such as acetone, due to inhomogeneous concentration distributions along the IR beam, and due to the overlap of the acetone signal with off-scale water peaks. The study also demonstrated that there was little effect on quantitative analysis from partial or complete IR beam blockages during measurement. Qualitative analysis of unexpected compounds using RS-FTIR was also evaluated. In addition, the ability of the RS-FTIR to detect a sudden release of chemicals was demonstrated in the study.

Acetates↗
PubMed1993

Comparison of three independent methods as estimates of platelet inhibition after a single dose of acetylsalicylic acid.

In order to assess the ability of three different (one in vivo, one ex vivo and one in vitro) methods to estimate platelet function, 10 healthy volunteers were given a single oral dose of 160 mg ASA. Platelet function was assessed before, 4, 24, 48 and 72 h after dosing by urinary excretion of thromboxane B2, filtragometry and collagen-based whole blood aggregometry. Further, in order to study mechanisms for platelet aggregation in filtragometry, platelet activation was assessed by measurements of beta-thromboglobulin at three different places within the filtragometer test unit in another nine healthy subjects. Four hours after ASA, the aggregation time during filtragometry increased by 213 +/- 133% (p < 0.001) and was parallelled by a decrease in impedance 85 +/- 7% (p < 0.001) indicating an inhibition of platelet aggregability in both tests. A subsequent gradual recovery was observed with both methods. The excretion of thromboxane B2 followed the aggregability pattern being maximally reduced by 72 +/- 6% (p < 0.01) 24 h after ASA and then gradually recovering. All three methods indicated that platelet function was still decreased 72 h after dosing. The urinary excretion of prostacyclin did not change significantly. The results of filtragometry and impedance aggregometry correlated to the logarithm of thromboxane B2 excretion (r = 0.60; p < 0.01 and r = 0.49; p < 0.01, respectively) and to each other (r = 0.70; p < 0.001). In filtragometry beta-thromboglobulin increased significantly (p < 0.05) over the filter.(ABSTRACT TRUNCATED AT 250 WORDS)

Aspirin↗
PubMed1993

[A case of pure gonadal dysgenesis treated laparoscopically].

In a 20-year-old patient with primary amenorrhoea with phenotypically female external reproductive organs, 46 XY genotype was found. Gynaecological examination, USG and CT showed small hypoplastic uterus and rudimentary ovaries. During the final stage of the diagnosis, laparoscopic assessment of the ovaries with their removal was performed. On histopathological examination gonadoblastoma was diagnosed.

Adult↗
PubMed1993

[Diagnostic innovations in electrophysiology. Variance ECG].

Variance ECG constitutes an important technological and methodological advance in electrocardiography (ECG). The variance index has been found to diagnose ischaemic heart disease at least as well as myocardial scintigraphy, and considerably better than exercise testing. Exercise testing detects acute myocardial ischaemia provoked by physical exertion, whereas resting variance ECG findings presumably reflect any deficiency in the regulation of electrical impulse distribution due to structural changes and chronic low-grade ischaemia that may occur in patients with coronary artery disease.

Coronary Disease↗
PubMed1993

[The course of sexual development in girls with diabetes type I in view of ultrasonographic examinations].

The gynecologic a ultrasonographic examinations in 34 insulin--dependent diabetic girls aged from 1-9 y, were performed. Diabetes duration oscillated between 1-9 y. The obtained results showed that the dynamics of sexual maturation of this girls was independent of theirs calendar age, but was conditioned by the time of obtained sexual development. The right metabolic balance of diabetes stipulates regular course of sexual maturation.

Adolescent↗
PubMed1992

Clinical evaluation of the Bentley Univox membrane oxygenator.

This paper reports a clinical evaluation of Bentley's new Univox membrane oxygenator (Bentley Laboratories, Irvine, California). In this new device, the blood flow path is outside the fibre, the incorporated heat exchanger consists of a 22-channel stainless-steel bellows, and the polypropylene fibres are woven into fibre ribbons and wound into each of the bellows channels. In this way, heat and gas transfers take place simultaneously. The priming volume has been reduced to 220ml and the membrane has an effective surface area of 1.6m 2. A BMR 1900 collapsible reservoir (Bentley Laboratories, Irvine, California) was used as a venous reservoir. Ten consenting patients undergoing elective coronary artery bypass surgery were perfused with this new oxygenator. BSA was between 1.7 and 2.11m 2; mean BSA was 1.81. Minimum priming was 1200 ml. The blood-gas results were all within or close to the normal range used in our institution. Acid-base management was performed using alpha-stat regulation and no problems occurred in this series of patients. Average pO 2 was 155mmHG+/-53 with a mean O 2 transfer of 90.7ml and a maximum of 185ml. The heat exchange performance was very good, with a mean coefficient of heat exchange of 0.54+/-0.11 and a maximum of 0.87.

Aged↗
PubMed1992

Immunoreactive glucagon and insulin in mammary secretion and blood in women during the periparturient period.

The concentrations of glucagon (G) and insulin (I) in the isolated when fraction of colostrum and plasma were determined by radioimmunoassay in 30 women on the last day of pregnancy, on the parturition day and during 7 consecutive postpartum days. The levels of G and I in colostrum were high on the last day of pregnancy (15.41 +/- 0.75 ng/ml and 256.9 +/- 32.7 microU/ml, resp.) and on the day of parturition (13.41 +/- 0.63 ng/ml and 279.5 +/- 41.9 microU/ml, resp.), while relatively lower values were observed on the next day (10.1 +/- 0.41 ng/ml and 194.7 +/- 19.3 microU/ml, resp.). During the next 4 days after parturition the concentrations of these hormones gradually decreased almost to the same basal level as observed in plasma. High hormone concentrations in mammary secretion during the periparturition period were probably caused by intensified transfer through blood-mammary gland barrier, and could reflect increasing needs for these hormones by developing mammocytes and by the newborns adapting to the extrauterine life. In conclusion, a high amount of G and I in mammary secretion may have physiological importance for the neonate. No statistically significant correlation in the hormone concentration between colostrum and plasma were noted.

Colostrum↗