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S Nowak

Publications and source records attributed to S Nowak.

At least 19 recordsLinked to original sources
PubMed2001

A Bose-Einstein condensate of metastable atoms.

We report the realization of a Bose-Einstein condensate of metastable atoms (helium in the lowest triplet state). The excitation energy of each atom with respect to the ground state is 20 electron volts, but inelastic processes that would destroy the sample are suppressed strongly enough in a spin-polarized sample to allow condensation. Our detection scheme takes advantage of the metastability to achieve detection of individual atoms as well as of the decay products of inelastic processes. This detection opens the way toward new studies in mesoscopic quantum statistical physics, as well as in atomic quantum optics.

Journal Article↗
PubMed2001

Differentiated reactivity of whole blood neonatal platelets to various agonists.

Neonatal platelets have been occasionally reported to show a reduced response to various agonists. The molecular mechanism(s) of such a depressed reactivity remains unclear. To further address this problem we studied neonatal platelet activation with thrombin, TRAP (thrombin receptor activating peptide, Ser-Phe-Leu-Leu-Arg-Asn-Pro-Asn-Asp-Lys-Tyr-Glu-Pro-Phe) and ADP in 42 healthy 1-2 day old neonates using a whole peripheral blood flow cytometry. The neonates did not show an increased fraction of P-selectin-positive circulating platelets, whereas the expression of GPIb (glycoprotein Ib) in resting neonatal platelets was significantly lower compared to adults. Neonatal platelets were significantly less reactive than adult platelets to thrombin and TRAP, especially at lower agonist concentrations, but not to ADP or when incubated for 1 h at room temperature. Activation of neonatal platelets with agonists resulted in a marked alterations in the expression of P-selectin, whereas the internalization of GPIb was not affected. The reduced neonatal platelet sensitivity to thrombin and TRAP was accompanied by significantly reduced ATIII (antithrombin III) and increased prothrombin fragment F(1+2) in neonatal plasma. We conclude that various receptor systems potentially able to bind thrombin are relatively insensitive in neonatal platelets. The novelty of our work is that neonatal platelet hyposensitivity is not a generalized phenomenon, but concerns only selected agonists and selected receptor systems.

Adenosine Diphosphate↗
PubMed2001

Selected serum cytokines in systemic lupus erythematosus treated with quinagolide.

The objective of this study was to determine the effect of quinagolide (Norprolac) on serum level of cytokines in systemic lupus erythematosus (SLE) patients. In 20 SLE patients treated with a low dose of quinagolide, and in 17 healthy persons who constituted the control group, concentration of serum prolactin (PRL), interleukins (ILs), soluble tumor necrosis factor receptors (sTNF Rs) preceded by calculation of disease activity index (SLEDAI) were tested at entry and then after 3 months in 16 patients and after 6 months in 11 patients who completed the study. Serum PRL level was higher (though insignificantly) in the SLE group than in the controls and decreased significantly after 6 months of therapy. A raised SLEDAI score at entry was significantly reduced during therapy but a weak correlation with PRL level was revealed. A significant increase in IL-6 level in SLE group as compared to controls was observed (respectively 14.57 +/- 13.25 and 5.04 +/- 3.35 microg/ml) as well as a significantly decreased level after 6 months of treatment (4.30 +/- 2.51 pg/ml). There was a significant difference between sTNF RI concentration before and after 3 months of quinagolide treatment (respectively 1140.83 +/- 312.08 and 1454.58 +/- 465.54 pg/ml). After 6 months of treatment a statistically significant correlation between concentration of PRL and level of IL-6 and a negative correlation between PRL and sTNF RI was revealed. Quinagolide treatment may have a role in the management of SLE patients.

Adult↗
PubMed2000

Dynamics of tearing modes during strong electron cyclotron heating on the FTU tokamak.

The localized electron cyclotron resonance heating power that can suppress sawteeth reconnection often drives m = 2 tearing modes in a tokamak operating at constant current. The dynamics of mode onset and coupled mode evolution is described in detail and compared with a nonlinear theoretical model that identifies the effects of mode coupling, finite inertia of the rotating islands, and wall braking.

Journal Article↗
PubMed2000

[Use of modern microscopic techniques for examining dialysis membrane properties].

The aim of the study was the microscopic evaluation of internal structure of cuprophane and polysulfone membrane and their surface analysis before and after reprocessing. The investigations were performed using an optical measurement system (Digital Instruments), a scanning electron microscope (SEM) and an atomic force microscope (AFM). We confirmed by SEM that reprocessing completely removed biofilm from both membranes surface. The analysis based on AFM visualized channels in the examined membrane. The diameter of the channels varied from 150 nm for cuprophane to 380 nm for polysulfone. The roughness expressed as root mean square (RMS) was higher for cuprophane than for polysulfone membrane. The physical differences between nanostrucure of the examined membranes might be responsible for lower biocompatibility of cuprophane.

Biocompatible Materials↗
PubMed1999

Ebb and flow rickets in a premature infant: the Afghan turban sign.

The pattern of alternating dense and lucent bands, with straight outer edges, at the youngest metaphysis of long bones, the "Afghan turban" sign, occurs when incompletely treated rickets has recurred and been retreated. Recognition of this, and other, rickets patterns allows the radiologist to influence treatment, as described in a very low birth weight infant.

Clavicle↗
PubMed1999

[Analysis of perinatal death at the Institute of the Health Center of the Polish mother in 1995, 1996 and 1997. The reason for making changes in the accountability for perinatal death].

Perinatal death's causes of fetuses and newborns from single and twin pregnancies delivered at the PMMHI from 1995-1997 were discussed. Data from the Pathology Department were analysed and compared to information regarding prenatal US + ECHO diagnoses coming from the Department for Diagnoses of Congenital Malformations at the PMMHI. The most frequent cause of death of fetuses and newborns from single pregnancies were congenital malformations (42%). In twins there prevailed such typical for multiple pregnancies' death causes as TTTS (27%), intrauterine demise of one of the twins (17%). Premature labor occupies the second most frequent cause of death both in single and multiple pregnancies. Most of perinatal deaths may be predicted prenatally by means of ultrasound and fetal echocardiography.

Catchment Area, Health↗
PubMed1999

[Myocardial scintigraphy with technetium 99m MIBI in patients with left bundle branch block].

UNLABELLED: Myocardial perfusion scintigraphy is a non-invasive method helpful for evaluating the coronary heart disease. Its use may be particularly indicated in cases of inconclusive ECG (i.e. in left bundle branch block, LBBB). On the other hand there are observations indicating the decreased accumulation of the radiotracer in the septal segments of myocardium in patients with left bundle branch block (LBBB). This phenomenon previously described for the thallium-201, recently was also reported in the MIBI 99mTc studies. Purpose of the present study were: (1) to check the frequency of the diminished uptake of the radiotracer (MIBI 99mTc) in the LBBB patients, and (2) to test its interference with the evaluation of the coronary heart disease. MATERIALS AND METHODS: Our observation material included 42 patients in mean age 49 +/- 7 yr (26 women) divided into 3 groups: Group I--12 patients without intraventricular conduction disorders and with normal coronarography (the reference group), Group II--15 patients with LBBB and no signs of coronary artery disease in angiography and Group III--15 patients with LBBB and coronary artery disease confirmed by angiography. All patients underwent stress-rest perfusion scintigraphy according to a 2-days protocol. Submaximal bicycle exercise test was performed using the Bruce protocol. A single-head SPECT scintillation camera (DIACAM-Siemens) was used to acquire 64 views over 180 degrees. Acquisition was started 60-90 minutes after injection of MIBI 99mTc (800 MBq). After generating tomographic images their reorientation towards the left ventricle axes and creating the bull's eye polar maps were carried out with the aid of manufacturer's programs. RESULTS: The mean decrease of the radiotracer accumulation in the septal segment was similar in both groups of patients with LBBB (32.7 +/- 9.5 vs 28.5 +/- 8.6 in stress and 27.6 +/- 9.5 vs 27.5 +/- 7.9 in rest in groups II and III, respectively). It was, however, significantly less pronounced in the reference (I) group (the mean decrease being 17.7 +/- 4.7 or 16.9 +/- 5.5 in stress and rest studies, respectively). Distribution of MIBI 99mTc in the myocardium was more homogeneous in the reference group (the maximal differences of the radiotracer accumulation never exceeded 45%) than in the LBBB groups. In the group II defects of the maximal depth over 46% were observed in 9 patients (60%), and in the group C in 12 patients (80%). In 6 patients of the latter group maximal depth of decets exceeded 56% (value never found in group II). CONCLUSION: The diminished uptake of MIBI 99mTc in the septal segment of the left ventricle is a common phenomenon. In some cases it may interfere with the evaluation of the perfusion scintigraphic studies. The more pronounced defects, however, may be significant for the coronary artery disease.

Bundle-Branch Block↗
PubMed1999

Bored dead meeting.

Explore the source record for details and available documents.

Chief Executive Officers, Hospital↗
PubMed1998

[The dipyridamole test in coronary disease diagnosis].

One of the coronary disease diagnostic methods of big sensitivity and specificity is perfusive effort scintrigraphy of myocardium by means of thallium-201. For few years the dipyridamole test has been applied instead of the effort test. Perfusive scintigraphy of myocardium after provocative treatment by means of dipyridamole and then selective coronary arteriography of coronary vessels, have been carried out at 25 patients with ischemia. These studies showed almost 100% of conformability with exposing the ischemia zones in scintigraphy and coronary arteriography in cases of coronary vessels contraction over 50%. The dipyridamole test also revealed the ischemzones in myocardium that are in agreement with coronary vascularization deficiency. That test can be utilized in revealing the coronary disease and is helpful in qualifying patients for coronary arteriography. At the same time studies that have been carried out prove that applying dipyridamole is absolutely contraindicated in treating of coronary disease of the organic background.

Adult↗
PubMed1998

Mobilization and collection of allogeneic peripheral blood progenitor cells for transplantation.

A median dose of 11 (6-17) microg G-CSF per kg and day was given to 96 (49 female, 47 male) healthy family donors in order to mobilize and to collect peripheral blood progenitor cells (PBPC) for allogeneic transplantation. Donor age was 36 (17-76) years. The leukocytes of the donors increased to 46 (12-115) x 10(9)/l on days 4-6 of G-CSF treatment with a median of 71 (2-657) CD34+ cells per microl, respectively. Female and older donors seem to have a lower response to G-CSF. About 32% of the donors suffered from side-effects of G-CSF requiring analgetics. A total of 197 stem cell aphereses were performed using the COBE Spectra cell separator. Median apheresis time was 225 (118-300) min processing 11.8 (5.7-20) l blood, collecting 5.3 (1.7-14.9) x 10(10) nucleated cells and containing 0.7 (0.1-3.7)% CD34+ cells. Severe citrate toxicity occurred in 5% of the donors. Retransfusion of autologous platelets post apheresis was necessary in 16% of the donors because of a platelet count <80 x 10(9)/l. An insufficient number of stem cells was collected in four female donors due to a very poor response to G-CSF. In conclusion, the collection of allogeneic G-CSF-mobilized PBPC is safe and effective. One or two aphereses were sufficient in 91% of the donors to achieve >4 x 10(6) CD34+ cells per kg. In 4% of the donors an additional bone marrow harvest or the use of an alternative donor was necessary because of a poor mobilization.

Adolescent↗
PubMed1997

Olfactory neuroblastoma: detection of genomic imbalances by comparative genomic hybridization.

Olfactory neuroblastoma (esthesioneuroblastoma) is a very rare tumour of the olfactory mucosa. Morphological features and cytogenetic studies strongly suggest a neuro-ectodermal origin. Up to now, cytogenetic studies are inconsistent. Some of them have proposed that the tumour belongs to the pPNET family. In the present study we describe genomic imbalances in olfactory neuroblastoma in a 46-year-old woman by using the molecular cytogenetic technique--comparative genomic hybridization (CGH)--in order to define the spectrum of genetic abnormalities in the tumour. The anatomical location and morphological findings were the basis for the diagnosis of esthesionearoblastoma. Immunohistochemical reactions for NSE, synaptophysin, chromogranin A, HNK-1/Leu-7 and S-100 revealed a characteristic immunophenotype. The CGH analysis showed multiple changes including DNA overrepresentations of chromosomes 4, 8, 11 and 14, partial DNA gains of the long arms of chromosomes 1 and 17, deletions of the entire chromosomes 16, 18, 19 and X, and partial losses of chromosomes 5q and 17p. This study represents an early utilisation of the CGH technique in olfactory neuroblastoma and demonstrates that the tumour carries complex chromosomal aberrations.

Biomarkers, Tumor↗
PubMed1997

Cardiovascular status after postural change in compensated cirrhosis: an argument for vasodilatory concept.

It seems that hypervolemia and vasodilatation coincide in compensated cirrhosis, but neither rank nor importance of these factors has been fully clarified in adaptive response to postural change. We studied, with gated equilibrium radionuclide angiography and thoracic electrical bioimpedance the hemodynamic status of 19 patients with compensated cirrhosis and 18 healthy subjects in upright and supine positions. In the upright position, the cirrhotic patients were hypotensive and had decreased peripheral vascular resistance despite increased cardiac output. The transition to the supine position was accompanied by a significant fall in the heart rate and an increase in the stroke volume in both controls (92 +/- 22 to 63 +/- 10 beats/min, and 38 +/- 9 to 62 +/- 19 ml/m2, respectively) and cirrhotic patients (101 +/- 20 to 79 +/- 13 beats/min, and 44 +/- 15 to 63 +/- 19 ml/m2, respectively). Besides, the diastolic arterial pressure fell in controls from 89 +/- 9 mmHg to 81 +/- 11 mmHg; p < 0.01, while it remained unchanged in cirrhotic patients (77 +/- 17 vs 82 +/- 13 mmHg). In the supine position, the cirrhotic patients presented tachycardia and left ventricular hyperkinesy (increased velocity of left ventricular filling and emptying). In conclusion, these results show that in compensated cirrhosis the decreased arterial tone and peripheral blood pooling are important factors of adaptive hemodynamic reaction to postural change.

Adult↗
PubMed1996

[vertebral and spinal cord tumors associated with scoliosis and kyphosis].

Eighteen cases of vertebral and spinal cord tumors associated with spine deformity are included in this study. Thoracic spine was involved most frequently. Neurological deficits were found in 14 patients. Surgical management was carried out in 14 cases. In 4 patients with complete transversal spine lesion percutaneous needle biopsy was done to establish the diagnosis. Surgery was supplemented by radiotherapy or radiotherapy and chemotherapy in 10 cases. Neurological improvement was found in 15 cases.

Adolescent↗