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Biomedical subjects

J Kaczmarek

Publications and source records attributed to J Kaczmarek.

At least 19 recordsLinked to original sources
PubMed2000

Sulfuric acid-catalyzed acetolysis of anomeric methyl 2,3,4,6-tetra-O-acetyl-D-mannopyranosides: kinetics and mechanism.

The kinetics of the acetolysis and accompanying anomerization of methyl 2,3,4,6-tetra-O-acetyl-alpha- and -beta-D-mannopyranosides at different concentrations of sulfuric acid in acetic anhydride-acetic acid mixtures were studied. The progress of the reactions was followed by gas chromatography, and the rate constants of the partial reactions were calculated on the basis of the time-dependent product distribution obtained. The mechanisms of the reactions involved are discussed. The involvement of unstable ionic intermediates is taken into account in the evaluation of the kinetic results, and simplified and extended models are used in the mathematical treatment of the results. A fourth-order Runge-Kutta algorithm is used to calculate rate constants. Acetolysis was found to be faster for mannosides than for glucosides relative to their anomerization. The beta-mannopyranoside prefers endocyclic CO-bond rupture, while in the alpha anomer the endocyclic and exocyclic cleavages are comparatively rapid.

Acetates↗
PubMed2000

Theoretical foundations for noninvasive measurement of variations in the width of the subarachnoid space.

Numerical modeling was used for the theoretical analysis of the propagation of optical radiation in the tissues of the human head, generated by a single source placed on the surface of the scalp. Of special interest and importance is the propagation of radiation within the layer of cerebrospinal fluid contained in the subarachnoid space (SAS), which is the only low absorption/high transmittance medium whose width can vary rapidly. Qualitative and quantitative assessment of changes in propagation of radiation within the SAS could become a source of information on changes in the geometry of this anatomical compartment playing a crucial role in cranio-spinal physiology and pathology. Essential for the idea of the possible noninvasive assessment of changes in width of the SAS by an optical method is the dependence of intensity of radiation reaching a photodetector located at a certain distance from the source on changes in the width of this fluid layer, which acts like a biological optical waveguide. Monte Carlo modeling and numerical analysis confirmed the feasibility of assessing changes in the width of the subarachnoid space optically. Presented here are details of the Monte Carlo simulation of light propagation in the tissues of human head and the results of such simulation as a function of the width of the subarachnoid space, calculated for different distances between the source and detector and for a few selected values of bone thickness. Results of numerical modeling were then compared with those of experiments on a mechanical-optical model.

Adolescent↗
PubMed2000

[Primary malignant melanoma of the larynx].

Primary malignant melanoma of the larynx is very rare. The case of larynx malignant melanoma in 71-years old men is presented. Hoarseness was the main complaint that encouraged the patient to visit a doctor. The patient was heavy smoker, he had been smoking 40 cigarettes for the last 50 years. He used to drink about 200 ml of pure alcohol per day. In the direct laryngoscopy gluish had cyanotic tumor, extending to the true vocal cord, ventricle, ventricle fold and subglottic space was seen. Enlarged cervical lymph nodes, laterally to the main vessels were found both in palpation and in US examination. Total laryngectomy and neck dissection was performed. The histological examination of surgical specimen revealed; Malignant melanoma. Metastases in the lymph nodes. Neoplastic infiltration of the nodal capsule. The patient was admitted to the complementary radiotherapy. At the moment the follow up in outpatient. The article contains the review of literature concerning the diagnosis, treatment and prognosis in cases of laryngeal malignant melanoma.

Aged↗
PubMed2000

[The role of PKC isoforms in tumorigenicity and apoptotic cell death].

Protein kinase C comprises a family of at least 13 distinct serine/threonine kinase isoenzymes that have important actions in transmembrane signal transduction pathways and have been reported to regulate cell proliferation, differentiation, cell-to-cell interaction, cytoskeletal functions, gene transcription, apoptosis and drug resistance. The results of investigations show differential redistribution isoenzymes in each organ and their specific activity in determined diseases.

Animals↗
PubMed1999

Impact of cardiovascular reactions using the impedance cardiography method in borderline hypertension.

This paper evaluates the hemodynamics of 30 young men, aged 17-19 years, with borderline hypertension (BHT) and 29 normotensive (NT) patients within the same age range. The study has been carried out using the impedance cardiography method at rest and under passive orthostatic test, cold test, and hyperventilation test. In the BHT patients, the following features have been observed: increased values of the cardiac index (CI), stroke volume index (SVI), mean blood pressure (MBP), and left ventricle work index (LVWI), as well as the accompanying normal values of the total peripheral resistance index (TPRI). The reactions of the cardiovascular systems during the functional tests are similar in both tested groups; however, they are most clearly distinct in the BHT patients, where the differences are statistically significant. This may support the argument that the activity of the adrenergic system in this group in intensified.

Adolescent↗
PubMed1998

The biochemical modification of the erythrocyte membranes from women with ovarian cancer.

The aim of our work was quantitative evaluation of the protein and phospholipid fractions of mature erythrocyte membranes separated from women with ovarian cancer. Blood was sampled from 30 women with ovarian cancer, aged 24-79 years, in the third stage of clinical progression of the disease. Phospholipids were separated from membranes by Müller's acidic extraction method and analysed in thin-layer two-dimensional chromatography. On the silica gel plates nine fractions of phospholipids were separated: sphingomyelin (SPH), phosphatidylethanolamine (PE), phosphatidlyserine (PS), phosphatidylcholine (PC), lysophosphatidylcholine (LPC), phosphatidic acid (PA), phosphatidylinositol (Ptd Ins), phosphatidylinositol-4-phosphate (Ptd Ins-4-P), phosphatidylinositol-4,5-diphosphate (Ptd Ins-4,5-P2). The activity of phospholipase C in erythrocyte membranes was determined by Akhrem's spectrophotometric method. Membrane proteins were separated by polyacrylamide gel electrophoresis, SDS-PAGE. It was shown that PS, SPH, LPC and PA fractions were significantly diminished. The concentration of Ptd Ins-4-P and Ptd Ins-4,5-P2 was significantly increased with simultaneous reduction in Ptd Ins level. The inhibition of phospholipase C reached 80%. The quantitative protein evaluation showed a statistically significant decrease in spectrin and a significant increase in 4.1 protein. The quantitative changes, observed in phospholipid and protein fractions, led to the restructuring of the erythrocyte membrane cytoskeleton, which may be connected to increased susceptibility to haemolysis of red blood cells.

Adult↗
PubMed1998

[Absorption and dispersion of ultraviolet radiation in human skin].

The study was carried out in a group composed of 48 men. The linear coefficient and linear coefficient of dispersion of ultraviolet radiation (UVR) in the skin was measured for different wavelengths. The mean values were determined for four types of the skin in both ultraviolet A (UVA) and ultraviolet B (UVB) ranges from 280 to 400 nm. The skin ability to absorb UVR decreases rapidly with decreasing wavelength. At wavelength of 280 nm, the coefficient of absorption changed within the range from 105 cm-1 (skin type II) to 160 cm-1 (skin type V), however, at wavelength of 400 nm it accounted only for 20 cm-1. A reciprocal relationship for scattering was found. The coefficient of dispersion changed within the range from 3.5 cm-1 at wavelength of 280 nm to 12 cm-1 at wavelength of 400nm. The mechanism based on absorption predominated at a shorter wave range (UVB), while at a longer range (UVA) the scattering mechanism was more efficient.

Adult↗
PubMed1998

[Prognosis of the skin UV-incidence increase in Poland].

The degradation of the ozone layer causes a real menace to human health. One of the most dangerous effects is the possibility of evoking skin cancer by the intensified UV-radiation level. The authors analysed the influence of ongoing changes on the increase in skin cancer cases in Polish conditions. Following the analysis, a 16-per cent increase in morbidity can be anticipated within the next decade.

Adult↗
PubMed1997

Sequential and parallel algorithms for DNA sequencing.

MOTIVATION: Reconstruction of the original DNA sequence in the sequencing by the hybridization approach (SBH) requires computational support due to a large number of possible combinations. One can notice a lack of algorithms admitting false-negative data and giving in addition all possible solutions. RESULTS: In this paper, a new method of sequencing has been proposed. An algorithm based on its idea (for the general case, when some data are missing, like in the real experiment) has been implemented and tested. Authentic DNA sequences have been used for testing. A parallel version of the algorithm has also been implemented and tested. The quality of the reconstruction is satisfactory for the library of oligonucleotides of length between 8 and 12, and 100, 200 and 300 bp long sequences. A way to a further decrease in the computation time is also suggested.

Algorithms↗
PubMed1996

[Aeroacoustic and pneumotachometric studies in the evaluation of vicarious voice in laryngectomy patients].

The aim the study was showed some spirometric and aerodynamic parameters of the respiratory system and of vicarious voice at laryngectomized patients, which were performed in plethysmographic cabin and by using of pneumotachometer. Clinical material stated 20 laryngectomized men, aged 45-77 years, who were divided into two groups (by Pruszewicz): A-well or very well speaking and B-bad speaking. The obtained results showed that laryngectomized well or very well speaking made bigger work of the respiratory system during vicarious voice than bad speaking ones. The well and very well speaking patients used twice (in case of consonants) and three times (in case of vowels) the volume of oesophageal-throat's air greater than bad speaking patients. Aerodynamic examinations in plethysmographic cabin allows for monitoring of vicarious voice at laryngectomized after operation and qualification some of ones for voice prosthetization in the aim of voice amplification.

Aged↗
PubMed1996

[An attempt of immunological monitoring of patients with laryngeal carcinoma by flow cytometry].

In a group of 60 patients with surgically treated laryngeal carcinoma blood lymphocyte subsets were assessed on the day of surgery (day 0) and six weeks thereafter by means of flow cytometry. Blood cells at day 0 were also compared to tumor infiltrating lymphocytes (TIL) isolated from surgical specimens. Significant alterations were found in postoperative period as compared to day 0 manifested by the fall of B cells, increase of activated T lymphocytes and NK cells. There were also marked changes between blood cells at day 0 and TIL, evidence in rise of B cells, of activated T lymphocytes and decline of NK cells within the latter. These data suggest that the assessment of lymphocyte subsets may be of value in immunological monitoring of laryngeal carcinoma patients.

B-Lymphocytes↗
PubMed1995

Modulation of cellular immunity by a lesion of the lateral hypothalamic area (LHA) in rats.

The subject of our investigation was the effect of bilateral damage to the lateral hypothalamic area (LHA) on the cellular immune response (CIR), assessed by measuring the diameter of skin infiltration (DSI) 24 and 48 h after intradermal administration of tuberculin in adult male Wistar rats, previously immunized with BCG vaccine. It has been shown that: 1) in the hypothalamo-lesioned rats (HLR) DSI measured 24 and 48 h after tuberculinization did not differ, 2) in the sham-operated rats (SOR) DSI measured 48 h after tuberculin injection was significantly higher (p < 0.02) than that found 24 h after the antigen administration, 3) the damage-induced loss of body weight and the 24-48 h difference in DSI in the responders of the HLR group correlated negatively with each other (r = -0.806, p < 0.05). These results indicate that damage to the LHA enhances the rate of formation, but not the maximal size, of the tuberculin-induced skin infiltration. Thus, the LHA seems to be involved in the regulation/modulation of processes engaged in the expression of tuberculin reaction.

Animals↗
PubMed1995

[Juvenile angiofibroma presented in the clinical materials of the Otolaryngological Department of the Academy of Medicine in Poznan in the years 1977-1993].

16 patients suffering from angiofibroma were treated in the Otolaryngological Clinic, Academy of Medicine in Poznań, in the years 1977--1993. The patients were aged from 10--36, the mean age 15. All patients were treated surgically, and the method choice was Denker's surgery. 3 patients were reoperated because of local relapse. On the bases of the described cases good results of full recovery of patients with angiofibroma treated surgically are presented.

Adolescent↗
PubMed1995

[Metastases in the prelaryngeal (delphian) lymph nodes in the course of the laryngeal cancer].

The metastases in the pre-laryngeal (Delphian) lymph nodes in the course of laryngeal cancer are uncommon. Between 1984 and 1994, 1573 patients with the diagnosis of laryngeal carcinoma were operated at the Department of Otolaryngology of Academy of Medicine in Poznań (Poland). Total laryngectomies were performed in 1069 cases and partial laryngectomies in 504 cases. Pre-laryngeal lymph nodes were identified in 109 patients. Histologically, metastases were found in 8 cases (7.48%). The prognosis of the patients with metastases in these lymph nodes is poor; only 2 patients are alive and free of neoplastic disease.

Humans↗
PubMed1995

Genetic and environmental conditions involved in assessment of the immunological state in children with atopic dermatitis.

78 children were subjected to an analysis of the genetic and environmental conditions which might predispose them to allergy. Some of the parameters of cellular and humoral immunity were estimated. Among the examined children there was a predominance of boys. 46,9% of all the children had a family history of allergy. Most of the children were bottle fed from birth. Some children had abnormalities of the cell-mediated and humoral immunity.

Child, Preschool↗
PubMed1995

[Evaluation of ultraviolet radiation reflectance for human skin].

In a group of 20 males aged 19-20 years ultraviolet radiation reflectance of different wavelength (250-400 nm) from skin surface was measured. It was found that the reflectance increased monotonically with the decrease of wavelength. The reflectance values were compared with the coefficient of relative spectral biological effectiveness and significance of both values for evaluation of human exposure to ultraviolet radiation was discussed.

Adult↗