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The results of Brillouin scattering investigations of two-component system: 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane/polyethylene glycol methacrylate (bis-GMA/PEGMM) containing 0, 30, 50, 70, 85 and 100 mol% of PEGMM are presented. For the first time the Brillouin spectroscopy was used to monitor the progress of the polymerization process. The polymerization was initiated by ultraviolet radiation (λ=365 nm), at temperature 20°C and 40°C. Some of the physical parameters characteristic for this system such as velocity V, adiabatic compressibility ß(ad) and attenuation coefficient α of the acoustic waves have been estimated from Brillouin spectra as a functions of the polymerization time. The obtained results have been discussed in terms of changes of the elastic properties of the two-component system occurring during polymerization process and their dependence on bis-GMA/PEGMM system composition.

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Brillouin spectroscopy was used to investigate viscoelastic properties of a two-component system consisting of a high viscosity liquid (HVL) and a low viscosity liquid (LVL), both able to polymerize. The model liquids were: 2,2-bis[4-(2-hydroxymethacryloxypropoxy)phenyl]propane (abbreviated as bis-GMA, HVL) and benzyl methacrylate (BzMA, LVL). The viscosity of the system was regulated by changing the monomer ratio. Hypersonic velocity and attenuation coefficient were investigated in a temperature range covering viscoelastic relaxation process. The dependence of the longitudinal viscosity on the system composition was determined. Additionally, the Brillouin studies were accompanied by some supplementary experimental methods, like low frequency shear viscosity measurements and observations of phase transitions by differential scanning calorimetry (DSC). The investigated monomer mixtures were then polymerized in a light-induced process and the polymerization kinetic curves were measured to find the possible correlation between the viscoelastic properties of the monomer mixture (as observed by Brillouin spectroscopy) and the polymerization course.

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We present results obtained by Brillouin scattering method for four two-component systems comprising of a high viscosity monomer and a low viscosity monomer. The monomers used were crosslinking (divinyl) or linear (monovinyl) ones. The investigated systems were: divinyl/divinyl-bis-GMA/TEGDM; divinyl/monovinyl-bis-GMA/PEGMM; monovinyl/divinyl-bis-MGMA/TEGDM and monovinyl/monovinyl-bis-MGMA/PEGMM; they were formulated at various molar ratios. The measurements have been performed in temperature range 293-353 K. The following physical parameters characterizing the investigated systems were estimated: hypersonic velocity V, attenuation coefficient α and adiabatic compressibility ß, all as a function of temperature and monomer molar ratio. The obtained results have been discussed in terms of the influence of the system composition and viscosity on their elastic properties. Speed of changes of the adiabatic compressibility ß as derivative have been also discussed in terms of both, the temperature as well as the component of molar ratio.

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The study was aimed at evaluating the involvement of sTNFR I, sTNFR II, IL-1 ra, IL-10, IL-13 and reactive oxygen species (ROS) in systemic inflammatory response syndrome (SIRS) development in severely burned children and at assessing the prognostic value of the immunological markers studied. The study comprised 37 patients (17 burned children and 20 controls). Serum levels of the markers determined by means of ELISA and respiratory burst of neutrophils as well as p55 and p75 tumour necrosis factor-alpha (TNF-alpha) receptor expression using flow cytometry were evaluated twice. The burned children presented significantly higher levels of IL-10 and cytokine inhibitors within the first 6-24 h after injury compared with controls (P < 0.05). The decreased oxygen metabolism of neutrophils and increased TNF-alpha receptor expression were found on admission. Moreover, a significant decrease in initially high sTNFR I, sTNFR II, IL-1 ra, IL-10, IL-13 concentrations (P < 0.05) and reduced expression of TNF-alpha receptors (P < 0.05) were observed after burn therapy, whereas ROS generation evidently augmented (P < 0.05). Four of our children who developed hypovolaemic shock revealed a significantly lower ROS generation and higher concentrations of soluble TNF-alpha receptors and IL-1 ra together with IL-10, IL-13 compared with children with good outcome (P < 0.05). Our results revealed the involvement of both ROS, soluble TNF-alpha receptors and IL-1 ra in the development of SIRS in burned children; their monitoring allows for an assessment of the systemic inflammatory reaction activity. The neutrophil BURSTTEST and IL-1 ra might have been clinically helpful markers of SIRS prognosis.

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Using immunohistochemical methods, we studied cellular infiltrations of burn wounds in children. The relative number of cells with cluster of differentiation 3 (CD3) CD68 molecules, cells with receptors for interleukin-2 (IL-2) and its receptor (IL-2R), IL-3, IL-3R, IL-6, IL-6R, tumor necrosis factor-alpha (TNF-alpha), TNF-alphaR, and cells with TNF-alpha molecules on their surface was studied. The relationships between these values were determined. The following results were observed: (1) A positive correlation between the relative numbers of CD68 cells and the percentage of cells with receptors for IL-2 (IL-2R) and TNF-alpha (TNF-alphaR); (2) A negative correlation between the relative numbers of CD3 cells and cells with receptors for IL-2 and TNF-alpha; (3) A strong negative correlation between the relative numbers of CD3 and CD68 cells; (4) A positive correlation between the percentage of cells with receptors for TNF-alpha and the size of the burn wound; and (5) A positive correlation between the relative numbers of cells with the TNF-alpha molecule on their surfaces and studied receptors for interleukins, i.e., IL-2R, IL-3R, IL-6R, and TNF-alphaR. These results indicate a key role for TNF-alpha and its receptor within the cytokine system in the course of the inflammatory reaction in burn wounds.

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Material was obtained from necrotic tissue excised from burn wounds in 60 children and examined immunohistochemically for the percentages of CD3, CD4, CD8, CD20, and CD68 cells. The results were then correlated with the burn surface area (BSA). Bacteriologic studies revealed the presence of bacteria in only 22 wounds with BSA greater than 10% of total body surface area. In this group, the proportion of CD3, CD4, CD8, CD20, and CD68 cells was correlated with the severity of infection, measured as the number of bacteria per g tissue. The results showed a positive correlation between the BSA and the percentage of CD8 cells (P < 0.001) and a negative correlation between CD4 cells and BSA (P < 0.02). The correlation between CD4/CD8 index and BSA was significantly negative. Likewise, a significant negative correlation was also noted between the percentage of CD4 and CD8 cells within the wound (P < 0.001). The severity of infection (bacteria/g tissue) was also positively correlated with the percentage of CD8 cells (P < 0.05) and negatively with the percentage of CD4 cells (P < 0.05). The correlation between CD4/CD8 index and intensity of infection was also highly significant. The results obtained show that in extensive burn wounds bacterial antigens may not be recognized properly due to the decreased percentage of CD4 cells and increased percentage of CD8 cells, which enhances bacterial growth in these wounds.

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The studies aimed at analysing the resistance to some beta-lactam antibiotics among E. coli and K. pneumoniae clinical isolates and at evaluating. The extended spectrum of beta-lactamases (ESBL) production in the isolates. The analysis included 137 E. coli strains and 52 K. pneumoniae strains, isolated from hospitalized patients and out-patients treated in the first trimester of 1998. The strains were identified using the ATB computer system. Antibiotic sensitivity of the isolates was determined by disc-diffusion tests. ESBL production capacity of E. coli and K. pneumoniae strains was estimated by double-disc and ATB BLSA tests. Most of the analysed E. coli strains were found to exhibit significant sensitivity to compound penicillin preparations containing beta-lactam inhibitor (Augmentin, Tazocin) and to the third generation cefalosporins, in contrast, K. pneumoniae strains much more frequently were resistant to the drugs. Among the obtained isolates, 3 (2.2%) E. coli strains and 21 (40.4%) K. pneumoniae strains produced ESBL but all the isolates proved sensitive to imipenem. In evaluation of ESBL production-detecting tests, the double-disc test was found to be more reliable than ATB BLSA test.

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A case of pulmonary actinomycosis in the child is described. Firstly, tumor of lung was suspected. Correct diagnosis was made after thoracotomy and histological examination of material.

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Periodontal condition was studied in 84 epileptic 8-18 year-old patients who had been undergoing antiepileptic drug (AEP) treatment for a period of at least 3 years. They were diagnosed as suffering from partial seizures (simplex or complex) or general tonic-clonic fits and were treated with therapeutic oral doses of phenytoin (PHT) and carbamazepine (CBZ) or valproic acid (VPA) in mono- or polytherapy. All patients received a drug dosage to ensure adequate plasma concentration and satisfactory seizure control. The Gingival Index (GI), Sulcus Bleeding Index (SBI) and Plaque Index (Pl-I) were individually scored. The control group contained 30 age-matched healthy children and adolescents. The GI and SBI indices were higher in epileptics than in controls. Only the Pl-I was similar in both groups. Gingival enlargement was found in 30% of the epileptic patients. There was no definite plasma concentration-dependent increase in the incidence of gingival overgrowth.

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The consequences of iodine deficiency occurring still in Poland include serious health disorders in the population, such as psycho- somatic retardation, hypothyroidism, endemic goitre, even cretinism. Administration of iodized edible salt with daily diet is an effective method for prevention of iodine deficiency. The condition of success is the proper level of potassium iodide in this salt and adequate distribution of iodized salt in various regions of the country. Successful iodine prophylaxis should be based on iodination of edible salt in amounts of 30 +/- 10 mg of KJ/kg. The permission given in the period from February to May 1994 by the General Sanitary Inspector for the production and marketing of edible salt iodized in proportions of 30 +/- 10 mg KJ/kg opened the possibility of starting its production in salt mines. The purpose of the presently reported work was to assess, in cooperation with the Province Sanitary Epidemiological Stations, the adequacy of iodination of the Polish edible salt produced in the years 1994-1995. The study was carried out according to the Polish Standard "Salt (Sodium Chloride) /PN-80/C-84081.35. Potassium iodide determination by photo colorimetric method." In 1995 the number of edible salt samples analyzed was 2484, and this number included 2129 samples of iodized salt. Potassium iodide content agreeing with the above permission was found in 122 samples, that is in 57.4% of iodized salt samples. In 603 samples (28.3%) of iodized salt this content was below that given in the permissions. In 1994 this study was carried out taking 2172 samples of edible salt, including 1586 samples of iodized salt. The content of potassium iodide agreeing with the permissions (30 +/- 10 mg/kg) was found in 342 samples (28, 1%), but 272 (22.4%) samples of iodized salt produced by salt mines contained lower amounts of potassium iodide than the amount indicated in the permissions, but still within the limits set down in the Polish Standard (20 +/- 5 mg/kg). The obtained results (57.4%) indicate an improvement of the process of salt iodination as compared with the results obtained in 1992 and 1993 (38.3%) and 1994 (28.1%). However, varying amounts of potassium iodide differing from the accepted values were found in salt declared as iodized.

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Staphylococcus aureus is a frequent pathogen of nosocomial infections. The main part in the spread of these microorganisms take symptomless carriers. The aim the research was defining the carrierstate of S. aureus among students of Medical Academy and University. The investigation showed a greater carrierstate in the group of Medical students (33%) than in the group of University students. Strains isolated from the Medical students were more differentiated in biochemical tests and they were more drug-resistant mainly to Augmentin (51.5% resistant strains) and doxycycline (24% resistant strains). A great percentage of ampicillin-resistant strains (94%) was found among the strains isolated from both groups. Results of the research showed greater carrierstate among people who had direct contact with patients and infectious materials and proved a wide range of drug-resistance among hospital strains. Carriers of S. aureus among medical personnel could influence the spreading of nosocomial infections mainly on ICU and Newborn Wards.

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This study describes results of in vitro examination of susceptibility to metronidazole of clinical strains of Helicobacter pylori isolated from patients with gastritis. The susceptibility was determined by disc diffusion test. H. pylori was isolated from 44 (67.7%) of patients. Thirty six (81.8%) of the strains were resistant to metronidazole: 17 (85%) from 20 strains isolated from women and 19 (79.2%) from 24 strains isolated from men. This study emphasises the importance of monitoring the drug resistance of H. pylori during therapy.

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The purpose of the study was to assess the correctness of salt iodination and its distribution in Poland. The subject of the study was salt for human consumption iodinated or not, according to Polish norm PN-88/C-84081/02 "Sól (chlorek sodowy). Requirements. Salt samples were taken from retail shops or stores in 36 provinces. The study was carried out in the years 1992-1993 according to PN-80/C-84081.35 "Sól (chlorek sodowy) standard. Potassium iodide was determined by photo-colorimetry. The total number of studied salt samples was 3418, including 2440 samples of iodinated salt. The per cent of samples with proper content of potassium iodide was from 30% to 50% depending on the producer. The study demonstrated that in most cases the process of salt iodination is done incorrectly.

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The study undertaken for assessment of the frequency of education difficulties and adaptation to school situation in elementary school is a continuation of previous studies on the frequency of neurological disturbances and psychomotor retardation in children with neurological abnormalities observed during the first days of life. In children with these early neurological abnormalities (n = 82) more frequent presence of educational difficulties and disturbances in adaptation to the situation in school were noted, in relation to controls (n = 84).

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