[The evaluation of detection rate of Mycoplasma hominis and Ureaplasma spp. using cultural technique and polymerase chain reaction].

In the clinical diagnostic laboratories of Chelyabinsk and St. Petersburg evaluation of detection rate of Mycoplasma hominis and Ureaplasma spp. was implemented using technique of polymerase chain reaction and cultural method. The reagents kits "Mycoplasma ACH-12" and "Ureaplasma ACH-12" were used to detect and determine antibiotics sensitivity of urogenital mycoplasma with determination of character of sensitivity of clinical isolates M.hominis and Ureaplasma spp. in sample of secretion of urethra and cervical channel. The results of study demonstrated that rate of detection of Ureaplasma spp. turned out significantly higher than M.hominis. The common coincidence of results in St. Petersburg between two techniques (polymerase chain reaction and cultural method) in case of detection of Ureaplasma spp. amounted to 97.5% and in case of detection of M.hominis - 93.5%.The common coincidence of the results in Chelyabinsk between two techniques (polymerase chain reaction and cultural method) in case of detection of Ureaplasma spp. amounted to 79.9% and in case of detection of M.hominis - 96.1%.

Robust removal of short-duration artifacts in long neonatal EEG recordings using wavelet-enhanced ICA and adaptive combining of tentative reconstructions.

The goal of this paper is to describe a robust artifact removal (RAR) method, an automatic sequential procedure which is capable of removing short-duration, high-amplitude artifacts from long-term neonatal EEG recordings. Such artifacts are mainly caused by movement activity, and have an adverse effect on the automatic processing of long-term sleep recordings. The artifacts are removed sequentially in short-term signals using independent component analysis (ICA) transformation and wavelet denoising. In order to gain robustness of the RAR method, the whole EEG recording is processed multiple times. The resulting tentative reconstructions are then combined. We show results in a data set of signals from ten healthy newborns. Those results prove, both qualitatively and quantitatively, that the RAR method is capable of automatically rejecting the mentioned artifacts without changes in overall signal properties such as the spectrum. The method is shown to perform better than either the wavelet-enhanced ICA or the simple artifact rejection method without the combination procedure.

[Non-contact experimental burns in rats]. / Nekontaktní experimentální popáleniny u potkanú.

Both healthy female rats of the Wistar strain (VELAZ breed) and those irradiated with a single whole-body dose of 5 Gy gamma radiation (60Co) were exposed on the back to non-contact infrared radiation (IR lamp with an output of 250 W: skin surface temperature at a distance of 3 cm from the crown of the lamp = magnitude of 110 +/- 2 degrees C) for time periods of 40 s, 20 s, 10 s (healthy) and 20 s (irradiated animals). The surface range of thermic damage to the skin was determined using planimetry and measuring the length and the width of the burn with the respect to an immediate contraction. The mean values of an immediate retraction of the burnt skin and the interval of reliability of their estimate (p < 0.05) were significantly lower in 10 s exposure and in whole-body irradiation rats after 20 s (magnitude of 5.6 +/- 2.5 % ... 10 s; magnitude of 12.56 +/- 3.86 % ... in irradiated animals) than the retraction of non-irradiated rats (magnitude of 15.98 +/- 4.86 % ... in 20 s; magnitude of 31.88 +/- 7.34 % ... in 40 s). For a period of 90 min after burning, no substantial changes were found in rectal temperature (33.4 degrees C to 35.4 degrees C). Before a thermic trauma the drop in the temperature from the skin surface reached cca 2 degrees C subcutaneously, after burning in the centre of the burn about 17 degrees C and 9 degrees C in other exposures using the IR lamp. The mean time of burn healing in non-irradiated animals was the shortest in 10 s exposure (magnitude of 17 +/- 2 days), the damage in the centre reaching II b degree while after 40 s exposure the burn reached IV degree and also the longest healing time (magnitude of 60 +/- 4 days). After 20 s exposure, the mean healing times in irradiated rats were longer (magnitude of 39 +/- 3) days and so the skin damage (III to IV degree) as compared with non-irradiated animals where the mean healing time amounted to (34 +/- 4) days, the burns being of III degree.

[Radioprotective effects of DDP]. / Radioprotektivní úcinek DDP.

The authors studied the effect of various DDP applications (sodium salt of dimethyl-dioxopiperazine thiosulfonate) in a dose of 45 mg/kg w. administered 10 min before irradiation, on the survival of female mice C57 and (CBA x C57BL/F1 after a single whole-body exposure to a sublethal dose of gamma rays (LD50/5 = magnitude of 15.495 +/- 0.781 magnitude of Gy and LD50/30 = magnitude of 7.864 +/- 0.018 magnitude of Gy). The depth of DDP protection effect on the haemopoietic stem cells was studied using the method of endogenous spleen colonies (ESC) of haemopoietic tissue. DDP radioprotective effect was also demonstrated after s. c. and i. m. application of this substance 10 min before 6 Gy of gamma radiation; it was shown by a prolongation of the survival time of experimental animals and by an increase in the number of individuals surviving till the 30th day after irradiation. Higher ESC numbers in the animals with DDP protection demonstrate survival of higher number of the haemopoietic stem cells and indicate that DDP is the biological active substance and contributes to the repair of haematopoiesis damaged by radiation and to the survival of irradiated animals.

Contribution to some radiobiological aspects of the investigation of radiosensitizers of hypoxic cells. Part IV: Radiosensitizing effect of metronidazole evaluated on the level of postirradiation changes of bone marrow cellularity in rats protected by induced hypoxia of lower body half.

Radiosensitizing effect of metronidazole (Entizol, Polfa, Poland) was tested on an experimental model of ischaemized bone marrow. The changes of bone marrow cellularity were recorded after whole body irradiation of rats protected with abdomen compression during irradiation. With an increasing dose of irradiation proportional and significant decrease of nuclear elements in bone marrow occurred the third day after irradiation. Metronidazole administered to unprotected rats (without compression) did not show any effect. The abdomen compression led to a pronounced radioprotection but metronidazole administration reduced this effect significantly. Ischaemization of the lower half of rat body produced on the level of bone marrow cellularity the protection corresponding to DRF (dose reduction factor) = 1.96 the third day after irradiation. DRF value decreased to 1.52 by metronidazole application which corresponds to ER (enhancement ratio) = 1.29.

Contribution to some radiobiological aspects of the investigation of chemical radiosensitizers of hypoxic cells. Part V: Metronidazole--dependence of its radiosensitizing effect on the dose, time interval of administration and hypoxia degree of the bone marrow evaluated according to the changes of its cellularity in rats.

In the experiments on female rats of Wistar strain the effect of metronidazole (Entizol - Polfa) was studied administrated in aqueous solution with a gastric pipette into the stomach. Dependence was analyzed on the dose of metronidazole, on the time interval of administration before irradiation and on the degree of hypoxia of bone marrow during irradiation induced in the lower part of the body and graded by the abdomen compression with an inflatable rubber cuff with overpressure 4, 6.7, 13.3 and 20 kPa. The effect of whole body irradiation (60Co source) was evaluated according to the changes of bone marrow cellularity (BMC) the third day after irradiation. The sensitizing effect of metronidazole increases rapidly up to dose of 30 mg/kg with rising dose of the drug, then at higher doses only slowly. With prolonging interval of the application of 600 mg/kg body weight the sensibilization increases and reaches the peak after 1-2 hours, then it gradually decreases till the complete disappearance after 10-15 hours. In both cases irradiation was carried out at abdomen compression corresponding to 20 kPa of overpressure in the rubber cuff. The induced hypoxia of bone marrow demonstrated a significant, protective effect, corresponding to the degree of abdomen compression which was reduced by metronidazole administration in the dose of 600 mg/kg. The reduction represents one half to one third of the protective value and is proportional to the degree of induced bone marrow hypoxia during irradiation.