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A Ciszewski

Publications and source records attributed to A Ciszewski.

18 recordsLinked to original sources
PubMed2006

Do nitric oxide donors mimic endogenous NO-related response in plants?

Huge advances achieved recently in elucidating the role of NO in plants have been made possible by the application of NO donors. However, the application of NO to plants in various forms and doses should be subjected to detailed verification criteria. Not all metabolic responses induced by NO donors are reliable and reproducible in other experimental designs. The aim of the presented studies was to investigate the half-life of the most frequently applied donors (SNP, SNAP and GSNO), the rate of NO release under the influence of light and reducing agents. At a comparable donor concentration (500 microM) and under light conditions the highest rate of NO generation was found for SNAP, followed by GSNO and SNP. The measured half-life of the donor in the solution was 3 h for SNAP, 7 h for GSNO and 12 h for SNP. A temporary lack of light inhibited NO release from SNP, both in the solution and SNP-treated leaf tissue, which was measured by the electrochemical method. Also a NO, selective fluorescence indicator DAF-2DA in leaves supplied with different donors showed green fluorescence spots in the epidermal cells mainly in the light. SNP as a NO donor was the most photosensitive. The activity of PAL, which plays an important role in plant defence, was also activated by SNP in the light, not in the dark. S-nitrosothiols (SNAP and GSNO) also underwent photodegradation, although to a lesser degree than SNP. Additionally, NO generation capacity from S-nitrosothiols was shown in the presence of reducing agents, i.e. ascorbic acid and GSH, and the absence of light. The authors of this paper would like to polemicize with the commonly cited statement that "donors are compounds that spontaneously break down to release NO" and wish to point out the fact that the process of donor decomposition depends on the numerous external factors. It may be additionally stimulated or inhibited by live plant tissue, thus it is necessary to take into consideration these aspects and monitor the amount of NO released by the donor.

Light↗
PubMed2000

Electrocatalysis of NADH oxidation with an electropolymerized film of 1,4-bis(3,4-dihydroxyphenyl)-2,3-dimethylbutane.

The oxidation of 1,4-bis(3,4-dihydroxyphenyl)-2,3-dimethylbutane, known also as nordihydroguaiaretic acid, on a glassy carbon electrode anodically pretreated in KCl solution gives rise to a stabile redox-active polymer containing the o-quinone moiety. The redox response of the modified electrode is typical for a surface-immobilized species. The modifier thickness can be easy controlled by a number of potential cycles applied during electropolymerization, and a surface coverage up to 1.1 x 10(-9) mol cm(-2) can be achieved. The film exhibits catalytic activity toward NADH oxidation. Characteristic kinetic constants for the mediated oxidation of NADH were derived from rotating disk experiments performed in phosphate or Tris/acetate buffers. The effects of film thickness, solution pH, and the presence of Mg2+ cation on the catalytic efficiency of the modified electrode were discussed and compared with literature data concerning related systems.

Antioxidants↗
PubMed1999

[Own experience with the use of Charnley hip arthroplasty and preliminary results of treatment in the materials of the Department].

Early clinical and radiological results of Charnley hip arthroplasties performed in 1995-1998 in Department of Orthopaedics and Traumatology of Zeromski's City Hospital in Cracow are presented. Control evaluation was made in 86 hips (76 patients) among 155 hips (170 patients) which were done in this Department. 97 per cent good results in clinical and 100 per cent good results in radiological evaluation were found in controlled group. In group of 170 alloplasties were 4.1 per cent local and none system complications. Results in this series confirm Charnley prosthesis as a most effective device in treatment of many hip pathologies.

Aged↗
PubMed1996

[Early and long-term outcome after coronary artery patency].

The role of percutaneous transluminal coronary angioplasty (PTCA) in the management of chronically occluded coronary arteries is still controversial. Percutaneous transluminal coronary angioplasty of chronic total occlusion is associated with relatively low success rates and a high incidence of restenosis. The purpose of this analysis was to determine, from the records of our institution, the efficacy and long-term outcome of angioplasty performed for chronic total occlusion defined as complete occlusion (Thrombolysis in Myocardial Infraction [TIMI] grade 0). PTCA was performed in 212 consecutive patients with chronically occluded coronary arteries and was successful in 125 (59%) patients. Complications were not observed. Successful initial PTCA was related to the clinical duration of occlusion and the type of guidewire (the primary success rate with the conventional guidewire was 49 (48%) versus 76 (69.1%) with Magnum Meier System p < 0.01). Repeat angiography was performed for 65 (52.0%) consecutive patients with successful initial PTCA and demonstrated restenosis in 34 (52.3%). 17 patients were successfully treated by a second PTCA. Restenosis or reocclusion was not clearly related to the residual stenosis post PTCA. In addition, the grade of collateral supply was not different in the vessels with and without restenosis.

Adult↗
PubMed1994

Reversal of ischaemic systolic and diastolic left ventricular dysfunction by successful coronary angioplasty in patients with non-Q wave anterior myocardial infarction.

The effect of PTCA on global and regional left ventricular systolic function, isovolumic relaxation, chamber and muscle stiffness were studied in 30 patients with angina pectoris, previous non-Q wave anterior myocardial infarction (AMI) and significant stenosis of the left anterior descending coronary artery (LAD). In 11 of the 30 patients the condition was stable, but it was unstable in 19. Left ventricular angiograms were obtained before and 4.85 +/- 3.67 months after PTCA. The RAO was in the 30 degree projection, with the silhouette of the left ventricle sliced into 90 regions; changes in left ventricular volume, pressure and anterior wall thickness during the full cardiac cycle, together with dp/dt were demonstrated. After PTCA, global ejection fraction increased from 68.77 +/- 5.96% to 76.57 +/- 3.18%, P < 0.001. Impaired contractility was found in 29/90 (32.2%) regions before PTCA and in 5/90 (5.6%) after PTCA, P < 0.001. The time constant of the isovolumic pressure fall decreased after PTCA (52.56 +/- 17.40 ms vs 39.61 +/- 11.26 ms, P < 0.01). Elastic chamber stiffness coefficient decreased (0.022 +/- 0.003 vs 0.008 +/- 0.004, P < 0.001) and peak rate of left ventricular filling increased (319.0 +/- 107.9 ml.min-1 vs 396.8 +/- 201.4 ml.min-1, P < 0.05) after PTCA. The muscle stiffness coefficient was within normal values before and did not change after PTCA. The study findings show that in patients with persistent angina pectoris after non-Q wave AMI, complex systolic and diastolic ischaemic dysfunction occurs. This dysfunction can be reversed after successful PTCA of LAD.

Adult↗
PubMed1991

[Dilated cardiomyopathy in children and adolescents. Diagnostic problems, clinical course and prognosis].

UNLABELLED: The clinical profile of 19 patients with dilated cardiomyopathy from 2 to 18 years old (mean age 13.4 +/- 4 years) was reviewed to detect any factors that might be predictive for their survival. Follow-up study ranged from 5 to 105 months (mean 39 +/- 33 months). All patients received digitalis + diuretics, 12 were managed with immunosuppression, 16 with antiarrhythmics. There were 12 survivors and 7 nonsurvivors: the 1-year mortality was 21.2%, the 2-years mortality was 35.8%. All deaths were within first 2 years. In 12 patients who survived 2 years, significant improvement was noticed in 9 cases. Endomyocardial biopsy was performed in 16 patients. Four of them with histological diagnosis of myocarditis survived and in 3 of them a considerable improvement was noticed. Half of 12 patients with nonspecific histological findings died (p less than 0.05). There was no significant difference between survivors and nonsurvivors in all following parameters: the incidence of severe heart failure (NYHA class III-IV) and severe ventricular arrhythmias (Lown III-IV), relative heart volume, echocardiographic LVDD, haemodynamic parameters--CI, LVEF, LVEDP, LVEDVI. CONCLUSIONS: Clinical, electrocardiographic, echocardiographic and haemodynamic data are nonpredictive for survival. The most dangerous period are the first two years of illness. In long term, improvement was noticed in half of patients.

Adolescent↗
PubMed1989

[Electrocardiographic and echocardiographic evaluation of cardiac changes in systemic scleroderma].

Cardiac abnormalities were studied using the clinical, electrocardiographic and echocardiographic methods in 66 patients with systemic scleroderma. Abnormal ecg was seen in 41 patients (62.1%), most frequently in form ventricular extrasystole (21.2%), incomplete block of the right bundle branch (12.1%), left ventricular and right atrial hypertrophy (10.6%) each, and the pattern suggesting the history of past myocardial infarction (7.6%). Abnormal echocardiographic results were found in 38 patients (57.6%). The most usual changes, differentiating that group from the controls, were: sluggish diastolic movement of the posterior wall of the left ventricle (40.7%), pericardial effusion (37.0%), elongation of the isovolumic relaxation time diastole phase (99.3 s.m.v. 81.1 ms, p less than 0.001) and right ventricular dilatation. There were no significant differences between the scleroderma and the control group as regards the indices of the contractility of the left ventricle: ejection fraction (EF), velocity of circumferential fibres shortening (VCF), diastolic size of the left ventricle and of the left atrium. The prevalence of the electrocardiographic and echocardiographic abnormalities in particular types of scleroderma (diffuse, acroscleroderma, severe acroscleroderma, CREST) was roughly similar: 50-76%. Finding of the impaired diastolic rather than systolic function of the left ventricle and of the similar prevalence of the cardiac abnormalities in the particular types of scleroderma is new and contradictory to the commonplace opinions.

Adult↗
PubMedDate not supplied

Dilated cardiomyopathy in children: clinical course and prognosis.

The clinical profile of 19 patients with dilated cardiomyopathy ages 2-18 years (mean 13.4 +/- 4 years) was reviewed to detect any factors that might be predictive for their survival. Follow-up range from 5 to 105 months (mean 39 +/- 33 months). Routine treatment consisted of digitalis and diuretics: 14 patients received antiarrhythmics, 6 received vasodilators, and 12 were managed with immunosuppression. There were 12 survivors and 7 nonsurvivors: The 1-year mortality was 21.2% and the 2-year mortality 35.8%. All deaths were within first 2 years. Of the 12 patients who survived 2 years, a significant improvement was noticed in 9. In 3 patients tachycardia-induced cardiomyopathy was diagnosed, and abolition of supraventricular tachycardia was followed by improvement and regression of cardiomegaly. Endomyocardial biopsy was performed in 16 patients. Four with a histologic diagnosis of active myocarditis survived, and in 3 of them a considerable improvement was noticed. Of the 12 patients with nonspecific histologic findings, 6 died (p < 0.05). There were no significant differences between survivors and nonsurvivors for any of the following parameters: incidence of severe heart failure (NYHA class III-IV) and severe ventricular arrhythmias (Lown class III-V), relative heart volume, echocardiographic left ventricular diastolic diameter and shortening fraction, and the hemodynamic parameters of cardiac index, left ventricular ejection fraction, left ventricular end-diastolic pressure, and left ventricular end-diastolic volume index.

Adolescent↗
PubMedDate not supplied

STM observation of steps and terraces on tungsten (211) surface.

Thermally cleaned W(211) surface with 0.7 degrees miscut consists of (211) terraces separated by monoatomic steps. When the surface is exposed to oxygen and subsequently annealed at 1100-1900 K, the width of (211) terraces increases and multilayer steps are formed. Similar step bunching is observed during routine cleaning of the sample by annealing in oxygen and thermal flashing in ultra high vacuum. During such cleaning procedure islands of c(6 x 4) reconstruction are observed.

Journal Article↗