Computed tomography (CT) is an effective diagnostic modality for three-dimensional imaging of bone structures, including the geometry of their defects. The aim of the study was to create and optimize 3D geometrical and real plastic models of the distal femoral component of the knee with joint surface defects. Input data included CT images of stifle joints in twenty miniature pigs with iatrogenic osteochondrosis-like lesions in medial femoral condyle of the left knee. The animals were examined eight and sixteen weeks after surgery. Philips MX 8000 MX and View workstation were used for scanning parallel plane cross section slices and Cartesian discrete volume creation. On the average, 100 slices were performed in each stifle joint. Slice matrices size was 512 x 512 with slice thickness of 1 mm. Pixel (voxel) size in the slice plane was 0.5 mm (with average accuracy of ± 0.5 mm and typical volume size 512 × 512 × 100 voxels). Three-dimensional processing of CT data and 3D geometrical modelling, using interactive computer graphic system MediTools formerly developed here, consisted of tissue segmentation (raster based method combination and 5 % of manual correction), vectorization by the marching-cubes method, smoothing and decimation. Stifle- joint CT images of three individuals of different body size (small, medium and large) were selected to make the real plastic models of their distal femurs from plaster composite using rapid prototyping technology of Zcorporation. Accuracy of the modeling was ± 0.5 mm. The real plastic models of distal femurs can be used as a template for developing custom made press and fit scaffold implants seeded with mesenchymal stem cells that might be subsequently implanted into iatrogenic joint surface defects for articular cartilage-repair enhancement., P. Krupa, P. Kršek, M. Javorník, O. Dostál, R. Srnec, D. Usvald, P. Proks, H. Kecová, E. Amler, J. Jančář, P. Gál, L. Plánka, A. Nečas., and Obsahuje bibliografii
This study appears from an experiment previously carried out in New Zealand white rabbits. Allogenic mesenchymal stem cells (MSCs) were transplanted into an iatrogenically-created defect in the lateral section of the distal physis of the left femur in 10 miniature pigs. The right femur with the same defect served as a control. To transfer MSCs, a freshly prepared porous scaffold was used, based on collagen and chitosan, constituting a compact tube into which MSCs were implanted. The pigs were euthanized four months after the transplantation. On average, the left femur with transplanted MSCs grew more in length (0.56±0.14 cm) compared with right femurs with physeal defect without transplanted MSCs (0.14 ± 0.3 cm). The average angular (valgus) deformity of the left femur had an angle point of 0.78°, following measurement and X-ray examination, whereas in the right femur without transplantation it was 3.7°. The initial results indicate that preventive transplantation of MSCs into a physeal defect may prevent valgus deformity formation and probably also reduce disorders of the longitudinal bone growth. This part of our experiment is significant in the effort to advance MSCs application in human medicine by using pig as a model, which is the next step after experimenting on rabbits., L. Plánka ... [et al.]., and Obsahuje seznam literatury
A comparison of the effects of ultrasound produced by low- and high-frequency ultrasonic apparatuses upon biological systems is one of the basic problems when studying ultrasound cavitation effects. One possibility for how to compare these effects is the indirect method which uses well-known physical quantities characterizing the interaction of ionizing radiation with matter and which also converts these quantities to one common physical quantity. The comparison was performed with two methods applied to the chemical dosimetry of ionizing radiation. The first method employed a twocomponent dosimeter which is composed of 50 % chloroform and 50 % re-distilled water (i.e. Taplin dosimeter). The other method used a modified iodide dosimeter prepared from a 0.5 M potassium iodide solution. After irradiation or ultrasound exposure, measurable chemical changes occurred in both dosimeters. The longer the exposure, the greater the chemical changes. These effects are described by the relationship of these changes versus the exposure times in both dosimeters. The UZD 21 ultrasonic disintegrator (with a frequency of 20 kHz, 50 % power output) was used as a lowfrequency ultrasound source, and the BTL-07 therapeutic instrument (with a frequency of 1 MHz and intensity of 2 W/cm2) was used as a high-frequency cavitation ultrasound source. For comparison, a 60Co gamma source was applied (60Co, gamma energies of 1.17 and 1.33 MeV, activity of 14 PBq). Results of this study have demonstrated that the sonochemical products are generated during exposure in the exposed samples of both dosimeters for all apparatuses used. The amount of these products depends linearly upon the exposure time. The resulting cavitation effects were recalculated to a gray-equivalent dose (the proposed unit is cavitation gray [cavitGy]) based on the sonochemical effects compared to the effects of ionizing radiation from the 60Co source., B. Kratochvíl, V. Mornstein., and Obsahuje bibliografii
Electrogastrography (EGG) is a non-invasive method for the assessment of gastric myoelectrical activity. Porcine EGG is comparable with human one. The purpose of this study was to evaluate the effect of atropine and neostigmine on the EGG in experimental pigs. Adult female pigs were administrated atropine (1.5 mg i.m., n=6) and neostigmine (0.5 mg i.m., n=6) after the baseline EGG, followed by a 90-min trial recording (MMS, Enschede, the Netherlands). Running spectral analysis was used for the evaluation. The results were expressed as dominant frequency of slow waves and EGG power (areas of amplitudes). Neostigmine increased continuously the dominant frequency and decreased significantly the EGG power. Atropine did not change the dominant frequency significantly. However, atropine increased significantly the EGG power (areas of amplitudes) from basal values to the maximum at the 10-20-min interval. After that period, the areas of amplitudes decreased significantly to the lowest values at the 60-90-min interval. In conclusion, cholinergic and anticholinergic agents affect differently EGG in experimental pigs., J. Květina, I. Tachecí, M. Pavlík, M. Kopáčová, S. Rejchrt, T. Douda, M. Kuneš, J. Bureš., and Obsahuje bibliografii
The purpose of this study was to determine the production of metalloproteinases (MMP) 2 and 9 following UV-B irradiation in human corneal epithelial cells and fibroblasts. Epithelial cells and fibroblasts were separated from human donor corneas and exposed to UV-B lamp irradiation for 20, 40, 80 and 120 s. Media samples were collected at 8, 24, 48 and 72 h and gelatinase A and B production was assayed by the ELISA test. Statistical significance of production was assessed by the paired t-test. Increased production of MMP-2 was found in human corneal fibroblasts in response to UV-B irradiation. A statistically significant production of MMP-2 was not observed in human corneal epithelial cells following UV-B exposure. We did not detect any increase in MMP-9 after irradiation in either epithelial cells or fibroblasts. MMP-2 is produced by the corneal fibroblasts in the acute phase after UV-B irradiation. MMP-9 is not released in vitro following UV-B irradiation damage and therefore does not directly participate in the pathophysiology of acute photokeratitis., I. Kozák, D. Klisenbauer, T. Juhás., and Obsahuje bibliografii
Inflammation and other immune responses are involved in the variety of diseases and disorders. The acute response to endotoxemia includes activation of innate immune mechanisms as well as changes in autonomic nervous activity. The autonomic nervous system and the inflammatory response are intimately linked and sympathetic and vagal nerves are thought to have anti-inflammation functions. The basic functional circuit between vagus nerve a nd inflammatory response was identified and the neuroimmunomodulation loop was called cholinergic anti-inflammatory pathway. Unique function of vagus nerve in the anti-inflammatory reflex arc was found in many experimental and pre-clinical studies. They br ought evidence on the cholinergic signaling interacting with systemic and local inflammation, particularly suppressing immune cells function. Pharmacological/electrical modulation of vagal activity suppressed TNF-α and other proinflammatory cytokines prod uction and had beneficial therapeutic effects. Many questions related to mapping, linking and targeting of vagal-immune interactions have been elucidated and brought understanding of its basic physiology and provided the initial support for development of Tracey's inflammatory reflex. This review summarizes and critically assesses the current knowledge defining cholinergic anti-inflammatory pathway with main focus on studies employing an experimental approach and emphasizes the potential of modulation of va gally-mediated anti-inflammatory pathway in the treatment strategies., I. Zila, D. Mokra, J. Kopincova, M. Kolomaznik, M. Javorka, A. Calkovska., and Obsahuje bibliografii
This study investigated the value of oxygen (O2) pulse curves obtained during cardiopulmonary exercise testing (CPET) for the diagnosis of coronary artery disease (CAD). Forty patients with known coronary anatomy (35.0 % normal, 27.0 % single-vessel and 38.0 % multivessel CAD) underwent CPET with radiotracer injection at peak exercise, followed by myocardial scintigraphy. O2 pulse curves were classified as: A-normal, B-probably normal (normal slope with low peak value); C-probably abnormal (flat, with low peak value); or D- definitely abnormal (descending slope). Sensitivity, specificity, positive and negative predictive values of the O2 pulse curve pattern (A or B vs. C or D) for the diagnosis of CAD were, respectively, 38.5 %, 81.3 %, 76.9 %, and 44.8 %. The concordance rate between the abnormal O2 pulse curve pattern and ischemia in myocardial scintigraphy was 38.1 %. Age and the extent of scintigraphic perfusion defect, but not the abnormal O2 pulse curve patterns (B or C or both combined) were independently associated with CAD. In conclusion, the O2 pulse curve pattern has low diagnostic performance for the diagnosis of obstructive CAD, and the abnormal curve pattern was not associated with myocardial ischemia defined by scintigraphy., A. De Lorenzo, C. L. Da Silva, F. C. Castro Souza, R. De Souza Leão Lima., and Obsahuje bibliografii
It is important to determine and clarify the variability of mammary carcinogenesis induction in animal experimental studies particularly in connection with chemoprevention projects. The circannual seasonal rhythms of hormone levels or various parameters within the immune system may involve factors participating in mammary gland carcinogenesis. In our study, 19 experiments were conducted and all of them lasted for about 25 weeks after chemical carcinogen administration (DMBA or NMU) under standard laboratory conditions. Females of two rat strains - a medium susceptible Sprague-Dawley strain and a very low susceptible Wistar:Han were used. We observed not only the effect of seasonal changes but also the effect of age after single or repeated carcinogen administration. The seasonal dependence of mammary carcinogenesis with higher tumor incidence during long days in comparison with winter short days has been demonstrated in Sprague-Dawley rats. In experiments on the Wistar:Han strain, certain features of seasonal character were recorded, although the very low susceptibility of this strain to mammary carcinogenesis might have influenced the results. A limited period of carcinogen administration in early puberty around postnatal days 43-46 (higher susceptibility), when compared to the period after postnatal day 50, is the factor significantly increasing incidence and frequency of mammary carcinogenesis in the Sprague-Dawley strain. Our results indicate the need to consider the effect of season and age of animals at the time of carcinogen administration on rat mammary carcinogenesis induction. However, the application of the results obtained in one strain of experimental animals may only lead to misleading conclusions., P. Kubatka, E. Ahlersová, I. Ahlers, B. Bojková, K. Kalická, E. Adámeková, M. Marková, M. Chamilová, M. Čermáková., and Obsahuje bibliografii
In the process of population screening for apo E gene polymorphism with the PCR and subsequent restriction analysis, we identified a female who demonstrated heterozygosity for an unusual restriction fragment caused by the loss of a CfoI restriction site. Sequence analysis of the apo E gene was performed and a carrier of the mutant allele with C - T substitution at cDNA position 3817 was identified, which caused an Arg136 - Cys change. The first-line relatives have been screened for this rare mutation with PCR and restriction analysis of PCR products. The complete lipoprotein parameters have been determined in the probands family. In the family, only one child had the same mutant allele as his mother had. The proband (7.49 mmol/l) with her siblings had hypercholesterolemia and a high body mass index (BMI 31.6 kg/m2). By contrast, her son had a normal lipid spectrum with normal BMI. We described the mutation apo E2* (Arg136 - Cys) in a family with elevated lipid levels, but there was no confirmation of the connection between this mutation and type III hyperlipoproteinemia or hyperlipoproteinemia at all. In the case of this mutation, other factors (mainly genetic) are important for the development of lipid metabolism disorders., J. A. Hubáček, J. Piťha, P. Stávek, G. Schmitz, R. Poledne., and Obsahuje bibliografii
The aim of the present pilot pharmacogenetic study was to analyse quantitative effects of sulphonylurea treatment in addition to metformin on parameters of glycemic control with respect to CDKAL1 genotypes in patients with type 2 diabetes. Effect of 6-month sulphonylurea therapy on glycemic control according to CDKAL1 genotypes was evaluated in 101 patients with type 2 diabetes who failed to achieve glycemic control on metformin monotherapy. CDKAL1 rs7756992 polymorphism was determined by melting curve analysis of small amplicon following real-time PCR. After sulphonylurea treatment fasting plasma glucose (FPG) levels were significantly different (p=0.045) among three CDKAL1 genotype groups (AA: n=49; AG: n=36; GG: n=16). In a dominant genetic model, carriers of the G-allele (AG+GG, n=52) achieved significantly lower FPG levels in comparison with patients with the AA genotype (6.90±1.08 vs. 7.48±1.12 mmol/l, p=0.013). Consequently, adjusted ΔFPG was significantly higher in the AG+GG compared to the AA group (1.48±1.51 vs. 1.02±1.33 mmol/l, p=0.022). Similar trend was observed for HbA1c levels, but the difference between the genotype groups did not reach the level of statistical significance. Relatively small number of included patients is a limitation of the present study. In conclusion, our results suggest that the magnitude of FPG reduction after 6-month sulphonylurea treatment in patients with type 2 diabetes is related to the variation in CDKAL1., Z. Schroner ... [et al.]., and Obsahuje seznam literatury