Activity of the tick Ixodes ricinus monitored in a suburban park in Brno, Czech Republic, in association with the evaluation of selected repellents.

The ever-increasing number of Lyme borreliosis patients led us to consider more effective procedures for disease prevention. The aim of our study was to monitor the annual activity and infectivity of Ixodes ricinus ticks in the Pisárky region, City of Brno, CR, and to test the responses of the locally-captured ticks to selected repellents. The result of regular one-hour-per-week monitoring in 2011 was the collection of ticks that directly reflected the highest number of Lyme disease patients (4,835) detected throughout the period of recording in the Czech Republic. The ticks were examined for spirochaetes by dark field microscopy. The positive samples were identified by PCR analysis, confirming that 76% of these were infected with Borrelia burgdorferi sensu lato. Ticks were most abundant in May and June, with August having the highest risk for spirochaetal infection. Tick activity was statistically correlated with temperature. The moving-object-bioassay was used to study repellent efficiency on the Ixodes ricinus nymphs captured in the above-mentioned suburban park. Five selected commercial repellents based on DEET (N, N-diethyl-3-thylbenzamide) showed statistically different effects on the non-repellent control group.

Attentional networks in euthymic patients with unipolar depression.

BACKGROUND: The capacity to focus and concentrate or to direct attention supports many aspects of cognitive functioning including short-term memory and higher-level cognitive functions. The purpose was to assess attentional networks in euthymic patients with unipolar depression using the Attentional Network Test (ANT). MATERIALS AND METHODS: We investigated performance of attention by virtue of ANT during remission from unipolar depressive disorder and tested a hypothesis that there are no differences between outpatient group (euthymic patients, N=32) and matched controls in attentional variables, the relationship of attentional networks and everyday cognitive failures. RESULTS: No differences between the groups in attentional networks were found and no relationship between attentional networks and cognitive failures was found. LIMITATIONS: One assessment during remission could be insufficient to recognize long-term pattern of cognitive functions. CONCLUSIONS: These data show non-impaired attentional networks possibly explained by sufficient level of remission and ameliorated influence of high education on cognition.

[Hippocampus, structure of the brain and schizophrenia]. / Hipokampus, morfologie mozku a schizofrenie.

Schizophrenia is a clinically heterogeneous state without clearly defined pathogenesis. This limits the classification approaches with consequent lack of ability for individual treatment strategies. It becomes evident that hippocampus is a key structure in the neuropathology of schizophrenia and a concept of hippocampal reduction as an endophenotype of schizophrenia was established. The biggest support came from MRI volumetric studies. Despite that, due to some inconsistent findings, clinical consequences of hippocampal shrinkage are not yet clear. Contemporary methods of brain imaging (computation morphometry, voxel-based morphometry) could help us to outline the concept of schizophrenia and to clarify the clinical consequences of brain structure changes.

[Present status and future of imaging methods in neuropsychiatry]. / Soucasnost a budoucnost zobrazovacích metod v neuropsychiatrii.

Introduction describes historical relations between neurology and psychiatry. Both disciplines are now much nearer to each other than before--they have received similar diagnostic tools and they have similar therapeutic methods. Psychiatry is considered to be an integral part of neuroscience. The article reviews findings on the structural and functional changes accompanying the most serious psychiatric diseases and the growing role of the brain imaging methods is depicted.

Differences in the regulation of the intracellular Ca2+-dependent serine proteinase activity between Bacillus subtilis and B. megaterium.

A rise of the intracellular serine proteinase activity (ISP) during postexponential growth of Bacillus subtilis was decreased by a temperature upshift from 35 degrees to 42 degrees C. However, the amount of both molecular forms of the major intracellular serine proteinase ISP1 determined by immunoblotting was similar at both temperatures or even slightly increased at 42 degrees C. The evolution of the ISP activity in B. megaterium showed an opposite temperature dependence, being faster during growth at 42 degrees C. The amount of immunologically detected ISP1 again did not correlate well with the enzyme activity. Moreover, most of the ISP1 molecules in cell-free extracts from B. megaterium were inactive and were activated by increasing the CaCl2 concentration up to 30 mM--unlike B. subtilis, where the enzymic activity was unaffected by Ca2+ concentration. These data suggest that the ISP1 activity in the two bacillar species during postexponential growth is regulated posttranscriptionally, but that the regulatory mechanisms differ.

Significance of P-glycoprotein expression in childhood malignant tumors.

Resistance to chemotherapy significantly affects the treatment results in various cancers. Multidrug resistance caused by P-glycoprotein expression is now widely studied in human malignancies. We present the results of P-glycoprotein expression examination in 91 tumor tissue samples obtained from children treated for different malignant tumors in the Dept. of Pediatric Oncology, Prague. The correlation between the level of P-glycoprotein expression and tumor histology, clinical outcome, use of therapy, relapse rate and metastatic disease was made. P-glycoprotein expression was found significantly more frequent in soft tissue sarcomas, neuroblastomas, and hepatoblastomas, and generally in disseminated disease. On the contrary, a high expression of P-glycoprotein was not found in malignant brain tumors and nephroblastomas. The data strongly support the possibility that the percentage of P-glycoprotein expressing cells in selected tumors (soft tissue sarcomas, neuroblastomas), may have a clinical importance.

Dermatophytoses in Prague, Czech Republic, between 1987 and 1998.

Over a 12-year period, from 1987 to 1998, the spectrum of aetiological agents isolated from 11208 patients (6265 females and 4943 males) suspected of having dermatomycosis was analysed in the mycological laboratory of the Department of Dermatology, Charles University, Prague. The most frequently examined locations were toenails (34.9%), feet (15.6%), fingernails (12.8%), toe webs (11%), trunk (10%) and hands (8.7%). Dermatophytes were isolated from 5605 (30.2%) of all 18528 samples examined. Among dermatophytes, the most common infectious agent was Trichophyton rubrum (90.2%) followed by Trichophyton mentagrophytes (6.6%), Microsporum canis (1.8%) and Epidermophyton floccosum (1.4%). Trichophyton verrucosum, Microsporum persicolor and Microsporum gypseum were rare. During this 12-year period the pattern of aetiological agents of dermatomycoses in Prague was relatively stable.

Detection of minimal bone marrow infiltration in patients with localized and metastatic Ewing sarcoma using RT-PCR.

Ewing sarcoma and related neoplasias are characterized by the presence of specific chromosomal translocations resulting in EWS/ETS gene rearrangements. Created EWS/ETS-oncogene fusion transcripts can be detected in up to 98% of ESFT and provide tumour-specific markers useful in diagnostics. Using RT-PCR for detection of this aberration we can reveal minimal amounts of tumour cells contaminating BM, blood or apheresis products. We have examined BM samples from 22 patients (21 newly diagnosed and one recurrent disease) with histologically confirmed ESFT for the presence of contaminating tumour cells in BM at the time of diagnosis. Sixteen patients presented with localized disease, six had distant metastases at the first presentation. Ewing sarcoma cells were detected in the BM of 5/16 (31%) patients with localized disease and 3/6 (50%) with clinically detectable metastases at diagnosis. BM smears prepared from the same aspirates evaluated by light microscopy were all negative, even in two patients with multiple bone disease. We have confirmed the high sensitivity of the RT-PCR assay for detection of minimal BM infiltration in localized and metastatic ESFT. We have found that more than a quarter of patients with localized ESFT have minimal BM infiltration. Although the clinical significance of the minimal disease detected at the molecular level remains unknown, RT-PCR evaluation may enable better stratification of patients into risk groups in the future.

Gene aberrations in childhood brain tumors.

We present the results of the examination of prognostic markers in 40 children suffering from brain tumors. Prognostic markers such as amplification of the N-myc and c-myc, deletion of the 17p, and DNA ploidy are indispensable factors for the determination of diagnosis. An increased number of c-myc gene copies was found in malignant brain tumors, especially embryonal, more often than reported in the literature. N-myc amplification occurs in our group seldom, but it seems to be a sign of worse prognosis in glial and embryonal brain tumors. DNA aneuploidy was not found very frequently, but in high-grade tumors only.

Low-level laser therapy after molar extraction.

OBJECTIVE: The aim of the study was to evaluate effect of the different frequencies of low-level laser radiation (diode 670 nm and Helium-Neon 632.8 nm) on the healing process after human molar extractions. Frequencies of 5 Hz, 292 Hz, and 9,000 Hz were used in experiments. Monitoring of secretory IgA and albumin level in saliva and changes in bone density were used as objective markers of biostimulatory effect. SUMMARY BACKGROUND DATA: From the literature, it is known that if the alveolus is irradiated after extraction along with the lingual and buccal bony wall, faster coagulation, less postoperative discomfort, and quicker healing can be expected. METHODS: Subjective evaluation of therapy was observed using a scale (from -, negative therapeutic effect, to ++++, excellent treatment effect). Changes of secretory immunoglobulin A (sIgA), albumin levels, and bone density were compared in a group of 150 patients (nonlaser therapy, 30 patients). RESULTS: Differences in levels of the saliva markers (sIgA and albumin) were found to be significant when comparing irradiated and nonirradiated groups, and in comparison with those groups irradiated by various modulatory frequencies. Significant differences were observed between the increase of sIgA res. albumin and subjective feelings during treatment. Bone density after extraction and 6 months after surgical treatment was examined using dental digital radiovisiography. No significant differences were detected between bone density in irradiated and nonirradiated groups, perhaps due to our therapy protocol. CONCLUSIONS: The low-level laser has no influence on the process of osseointegration. This effect was observed on fracture healing in rats using He-Ne laser radiation. We found no differences in the bone density when compared to the control group.

In vivo and In vitro function of the intracellular proteolytic apparatus in nongrowing bacillus megaterium under heat stress

In Bacillus megaterium sporulating at 35 degreesC, up to 90% of 10-min pulse-labeled proteins were degraded. Degradation proceeded in two waves. Short-lived proteins, i.e., intrinsically labile proteins and proteins made short-lived because of starvation, were mostly degraded during the reversible sporulation phase. Their amount corresponded to 20% or slightly more during 2 h. The second wave of protein degradation, which followed during the irreversible sporulation phase at 35 degreesC, increased the amount of total degradable pulse-labeled proteins to about 90%. This wave was absent in the isogenic asporogenic mutant 27-36 or in the wild strain, whose sporulation was inhibited by increased temperature. The proportion of degradable proteins was thus reduced to less than 40% in the asporogenic mutant incubated at 35 degreesC and to 46% in the wild strain whose sporulation was suppressed by the temperature of 47 degreesC. Unlike sporulating cells, these cells were thus capable of degrading short-lived and denatured proteins, but were not able to degrade most of other proteins. The in vitro protein degradation was substantially enhanced by increasing the Ca2+ concentration, suggesting a role of Ca2+-dependent proteinase(s) in the process.

Cell viability and protein turnover in nongrowing Bacillus megaterium at sporulation suppressing temperature.

In Bacillus megaterium, a temperature that suppresses sporulation (43 degrees C) only slightly exceeds both the optimum growth temperature and the temperature still permitting sporulation (40-41 degrees C). Here we show that, when cells grown at 35 degrees C and transferred to a sporulation medium, were subjected to shifts between 35 degrees C and the sporulation suppressing temperature (SST, 43 degrees C), their development and proteolytic activities were deeply affected. During the reversible sporulation phase that took place at 35 degrees C for 2-3 h (T2-T3), the cells developed forespores and their protein turnover was characterized by degradation of short-lived proteins and proteins made accessible to the proteolytic attack because of starvation. During the following irreversible sporulation phase refractile heat-resistant spores appeared at T4-T5. Protein turnover rate increased again after T2 and up to T8 60-70% prelabelled proteins were degraded. The SST suppressed sporulation at its beginning; at T3 no asymmetric septa were observed and the amount of heat-resistant spores at T8 was by 4-5 orders lower than at 35 degrees C. However, the cells remained viable and were able to sporulate when transferred to a lower temperature. Protein degradation was increased up to T3 but then its velocity sharply dropped and the amount of degraded protein at T8 corresponded to slightly more than one-half of that found at 35 degrees C. The cytoplasmic proteolytic activity was enhanced but the activity in the membrane fraction was decreased. When a temperature shift to SST was applied at the beginning of the irreversible sporulation phase (T2.5), the sporulation process was impaired. A portion of forespores lyzed, the others were able to complete their development but most spores were not heat-resistant and their coats showed defects. Protein degradation increased again because an effective proteolytic system was developed during the reversible sporulation phase but the amount of degraded protein was slightly lower than at 35 degrees C. A later (T4) shift to SST had no effect on the sporulation process.

Noncontact Er:YAG laser ablation: clinical evaluation.

OBJECTIVE: The aim of this study is to evaluate the quality of laser ablation in comparison with the classical drilling preparation. METHODS: For the experiment, the Er:YAG laser drilling machine was used. The system had a laser head, water cooler, and power supply with automatic control. Spot size of 300-350 microns was used for the preparation. Repetition rate of 1-4 Hz, and pulse energies of 100-400 mJ with water spray were chosen. Cavity shape in comparison with classical drill, time of preparation, and influence of cavity shape on filling materials retention in accordance with the U.S. Public Health Service System were used. The evaluation criteria for noncontact Er:YAG ablation were done. RESULTS: The cavity shape is irregular, but spot surface has larger area and microretentive appearance. Caries of enamel and dentin were treated with a noncontact preparation. It was possible to remove the old insufficient fillings, except for amalgam or metal alloys. The average number of pulses was 111.22 (SE 67.57). Vibrations of microexplosions during preparation were felt by patients on 14 cavities; however, nobody felt unpleasant pain. The qualities of filling materials in laser cavities were very stable; however, cavo surface margin discoloration of 82-86% of Alfa rating could be a problem. Changes of the color and anatomic form of the tooth were observed in 4-8%. CONCLUSIONS: In comparison with the classical treatment, it could be said that the retention and quality of filling materials is the same or very similar.

Effect of pH on proteinase secretion by transformed fibroblast populations.

Effect of pH on secretion of proteolytic enzymes in cell cultures of three clonal lines of transformed fibroblasts (K2, T15 and K4) was studied by using 14C-labelled denatured proteins as substrate. One line of malignant macrophages derived from mouse reticulum cell sarcoma (J774.1) was used for comparison. The relative motility index of all cell lines was derived by computer analysis of quantitative estimations of cell dispersion in single-cell-derived colonies. Cultivation at pH 6.5 decreased the growth rate in most experiments as compared with that at pH 7.4, and stimulated cell motility to a different extent. The population of mouse malignant macrophages produced several-fold higher extracellular proteolytic activity than the fibroblast lines. Secretion of proteinases by the malignant macrophages was significantly stimulated by the lower pH. Enzyme secretion by two of the three fibroblast derivatives was also stimulated by acidic pH but to a lesser extent than the secretion of the malignant macrophages. The assessment of motility done by measurement of dispersion of cells in colony proved a positive correlation between motility and proteinase secretion in J774.1 cells and one transformed fibroblast clone (T15) but not in the two other clonal lines.

Asporogenic Bacillus megaterium mutant 27-36 degrades intrinsically short-lived proteins but fails to convert most of other proteins to a short-lived fraction.

Asporogenic mutant blocked in the 0-II sporulation stage degraded pulse-labelled proteins in the sporulation medium at the same rate as the parental strain for the first two hours. The degraded fraction was mostly composed of intrinsically short-lived proteins which were degraded even after enriching the medium with amino acids and growth resumption. Proteins accessible to degradation because of nutritional shift down formed a lesser proportion of this fraction. The acceleration of protein turnover in the parent strain during the irreversible sporulation phase was not developed in the mutant. A first order kinetic model of protein degradation was used for parameter estimation. Ca(2+)-dependent intracellular serine proteinase was synthesized in an inactive form, which was activated by increasing Ca2+ concentration to 30 mM.

Intracellular serine proteinase behaves as a heat-stress protein in nongrowing but as a cold-stress protein in growing populations of Bacillus megaterium.

A temperature increase from 35 degrees to 40-42 degrees C enhances the rise of cytoplasmic serine proteinase (ISP1) activity in Bacillus megaterium incubated in a sporulation medium. A temperature shift from 27 degrees C in the growth medium to 35 degrees C in the sporulation medium has the same effect. Elevated temperature stimulates the increase of ISP1 level when applied immediately after the transfer of cells from the growth to the sporulation medium (at T0) or at T3, when sporulation becomes irreversible. The cytoplasmic PMSF-resistant activity or the proteolytic activity associated with the membrane fraction is stimulated only slightly or not at all. A temperature increase to 45-47 degrees C suppresses the rise of proteolytic activities in all cell fractions. In addition to the elevation of the ISP1 activity by an upward temperature shift, the rise of this enzyme in nongrowing cells is also stimulated by osmotic stress. In growing populations, in contrast to the rise of the ISP1 activity caused by elevated temperature in nongrowing cells, this proteinase is induced by low temperatures (24-27 degrees C). The ISP1 activity roughly correlates with the enzyme protein concentration determined by immunoblotting.

Heat and osmotic stress enhance the development of cytoplasmic serine proteinase activity in sporulating Bacillus megaterium.

The intracellular Ca(2+)-dependent serine proteinase (ISP1) activity in the cytoplasm of nongrowing Bacillus megaterium incubated in a sporulation medium was determined at 35 degrees C and at temperatures decreasing the sporulation frequency (42 degrees C) or suppressing sporulation (43.5 degrees C). The enzyme in the crude cytoplasmic fraction was partially inhibited by a loosely bound inhibitor(s) because the ISP1 activity rose after protein fractionation by HPLC. Temperature shift-up or osmotic stress applied at 35 degrees C increased the development of the ISP1 activity several times. The increase was caused at least partially by the synthesis of the enzyme protein, as proved by SDS-PAGE and immunoblotting of the cytoplasm. This enzyme thus probably belongs among heat-shock proteins.

Netropsin inhibits the increase of intracellular Ca(2+)-dependent serine proteinase activity in sporulating Bacillus megaterium.

Netropsin suppressed the increase of intracellular proteolytic activity when added to B. megaterium incubated in a sporulation medium. The inhibited enzyme was a Ca(2+)-dependent serine proteinase. Sporulation and protein turnover in later sporulation phases were inhibited as well. Different concentrations of netropsin affected various aspects of protein catabolism differently.