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Introduction: The comparison of tissue quality and its restoration after contact, and non-contact Er: YAG (2940 nm) laser radiation ablation was evaluated. Methods: Laser setting for contact ablation was 250 mJ/pulse, pulse repetition rate 15 Hz, average power 3.75 W. For non-contact ablation these values were: 600 mJ/pulse, 6 Hz, 3.6 W. Structure of enamel and dentin after laser ablation was analyzed in scanning electron microscope. All cavities were filled by sonic-activated composite resin. Chemical and mechanical bond was observed in scanning electron microscope.Microleakage was assessed quantitatively by the degree of methylene blue dye penetration. Fischer exact test (p < 0.05) was used for statistical evaluation. Results: Contact and non-contact laser treatments prepared similar cavities (5167.31 μm versus 5356.31 μm). Defocusing of non-contact therapy has direct influence on the dye penetration microleakage presence (481.19 μm versus 611.94 μm) but this increase was not statistical significant. Conclusion: Cavity prepared by contact mode with sonic-activated composite filling protects microleakage formation.

Introduction: Plaster casts present golden standard in keeping patients data in 3D. The aim of this work was (1) to compare linear measurements made on traditional plaster casts and 3D printed copies of dental plaster casts, (2) to find new possibilities of reconstruction of digital data, its reliability based on various criteria and (3) to determine whether 3D printed copies obtained using open source system RepRap can replace traditional plaster casts in dental practice. Material and methods: 10 dental plaster casts from the Orthodontic department, Department of stomatology for children and adults, 2nd Faculty of medicine, Charles University Prague, Czech Republic were scanned by inEos Blue scanner and printed on 3D printer RepRap. Linear measurements between selected points on the dental arches of upper and lower jaws on plaster casts and their 3D copies were recorded and statistically analyzed. Results: Use of 3D printed copies has many advantages over use of traditional plaster casts, mainly mechanical durability and keeping the data in digital form unless needed for example for forensic reasons. The precision and accuracy of the RepRap 3D printed copies of plaster casts were confirmed based on the statistical analysis. Our study proved that 3D printed copies can replace traditional plaster casts and it is possible to use them for detailed analysis.

Aim of Review: The purpose of this paper is to present a comprehensive overview of views on the treatment in patients with cleft lip and palate (CLP), primary lip repair, lip reconstruction in the neonatal period, including knowledge of fetal tissue healing. Background: Authors try to summarize the principles of stomato-orthodontic follow-up care. Orofacial clefts are the most common congenital developmental defects. Based on the statistical data, the mean incidence of all types of cleft defects in the orofacial area is 1.86 per 1000 live-born children Etiology is multifactorial. With respect to the range of the defect, the cooperation of a number of experts is required, and complicated and long-lasting therapies are necessary, especially for successful jaw growth. It is necessary to postpone a definitive solution to that time when the arches are in the growth phase. The multidisciplinary therapy involves the following disciplines: plastic surgery, orthodontics, speech pathology, psychology, otorhinolaryngology, genetics, pediatrics, and social work. Due to the extent of affliction, interdisciplinary co-operation is necessary and usually complicated and long-term therapy, which is needed especially for gradual growth of the jaw bones. Therefore, the final solution has to be postponed to a time when the arches are not in a growth period. The treatment should be initiated with a surgical lip correction (usually in the 3rd month of age of a child or fetal healing can be used) and later with a correction of the palate (between the 1st - 4th years of age). It should be followed by orthodontic therapy that optimally achieves correction (e.g. in an isolated palate cleft) but a final prosthetic solution is needed more often (especially in complex clefts). A favorable shape and size of the dental arches without anomalies is an important factor for the prosthetic phase. A cleft defect often means that some teeth are missing (lateral incisors, more often premolars) and there may be other orthodontic anomalies which include either crossed occlusion, inverse occlusion in the frontal part or various anomalies of a tooth position (inclination, rotation, etc.). Early prosthetic therapy (usually around 18 years of age) including implant insertion finalized treatment.

The active role of biomaterials in the regeneration of tissues and their ability to modulate the behavior of stem cells in terms of their differentiation is highly advantageous. Here, polypyrrole, as a representantive of electro-conducting materials, is found to modulate the behavior of embryonic stem cells. Concretely, the aqueous extracts of polypyrrole induce neurogenesis within embryonic bodies formed from embryonic stem cells. This finding ledto an effort to determine the physiological cascade which is responsible for this effect. The polypyrrole modulates signaling pathways of Akt and ERK kinase through their phosphorylation. These effects are related to the presence of low-molecular-weight compounds present in aqueous polypyrrole extracts, determined by mass spectroscopy. The results show that consequences related to the modulation of stem cell differentiation must also be taken into account when polypyrrole is considered as a biomaterial.

The present study is designed to find out if sesquiterpenes, α-humulene (HUM), valencene (VAL), β-caryphyllene-oxide (CAO) and trans-nerolidol (NER), are able to improve the antiproliferative effect of classical cytostatic drugs, 5-fluorouracil (FU) and oxaliplatin (1,2-diaminocyclohexaneoxalato-platinum, OxPt), in colon cancer cell lines Caco-2 and SW-620. In addition, the possible mechanisms of sesquiterpene action are studied. The results show significant ability of HUM and especially of CAO to enhance the anti-proliferative effects of FU and OxPt in cancer cell lines Caco-2 and SW-620. On the other hand, VAL and NER are ineffective. The action of CAO could be partly based on its ability to disrupt the mitochondrial membrane potential and to activate initiator caspases, but other mechanisms are probably also involved. Based on these results, CAO seems to have the potential for combination therapy of colon cancers and deserves further study.

Background: Plaster casts of individual patients are important for orthodontic specialists during the treatment process and their analysis is still a standard diagnostical tool. But the growing capabilities of information technology enable their replacement by digital models obtained by complex scanning systems., Method: This paper presents the possibility of using a digital camera as a simple instrument to obtain the set of digital images for analysis and evaluation of the treatment using appropriate mathematical tools of image processing. The methods studied in this paper include the segmentation of overlapping dental bodies and the use of different illumination sources to increase the reliability of the separation process. The circular Hough transform, region growing with multiple seed points, and the convex hull detection method are applied to the segmentation of orthodontic plaster cast images to identify dental arch objects and their sizes., Results: The proposed algorithm presents the methodology of improving the accuracy of segmentation of dental arch components using combined illumination sources. Dental arch parameters and distances between the canines and premolars for different segmentation methods were used as a measure to compare the results obtained., Conclusion: A new method of segmentation of overlapping dental arch components using digital records of illuminated plaster casts provides information with the precision required for orthodontic treatment. The distance between corresponding teeth was evaluated with a mean error of 1.38% and the Dice similarity coefficient of the evaluated dental bodies boundaries reached 0.9436 with a false positive rate [Formula: see text] and false negative rate [Formula: see text].

Background: Diagnostic orthodontic and prosthetic procedures commence with an initial examination, during which a number of individual findings on occlusion or malocclusion are clarified. Nowadays we try to replace standard plaster casts by scanned objects and digital models., Method: Geometrically calibrated images aid in the comparison of several different steps of the treatment and show the variation of selected features belonging to individual biomedical objects. The methods used are based on geometric morphometrics, making a new approach to the evaluation of the variability of features. The study presents two different methods of measurement and shows their accuracy and reliability., Results: The experimental part of the present paper is devoted to the analysis of the dental arch objects of 24 patients before and after the treatment using the distances between the canines and premolars as the features important for diagnostic purposes. Our work proved the advantage of measuring digitalized orthodontic models over manual measuring of plaster casts, with statistically significant results and accuracy sufficient for dental practice., Conclusion: A new method of computer imaging and measurements of a dental stone cast provides information with the precision required for orthodontic treatment. The results obtained point to the reduction in the variance of the distances between the premolars and canines during the treatment, with a regression coefficient RC=0.7 and confidence intervals close enough for dental practice. The ratio of these distances pointed to the nearly constant value of this measure close to 0.84 for the given set of 24 individuals.

Aim: Increased serum or urinary concentrations of neopterin are predictive of poor prognosis in patients with tumors across a spectrum of primary locations. Less information is available about the significance of changes of urinary neopterin concentrations during therapy. The aim of the present study was to examine the association between urinary neopterin and toxicity of radiotherapy., Patients and Methods: We analyzed changes of urinary neopterin and toxicity of therapy in 12 patients with head and neck carcinoma during external-beam radiation. Urinary neopterin was determined daily by high-performance liquid chromatography., Results: In addition to a trend for increased neopterin concentrations during radiation therapy, a significant association between changes of neopterin and toxicity and vice versa was observed with a rise of neopterin predicting a later manifestation of toxicity as well as manifestion of toxicity predicting a later rise of neopterin., Conclusion: Urinary neopterin is predictive of toxicity in patients with head and neck carcinoma. An association between toxicity and subsequent rise of urinary neopterin concentrations was also observed.

Aim: To investigate the relation between intima-media thickness (IMT) and laboratory parameters of atherosclerosis risk in patients with breast carcinoma., Patients and Methods: IMT and a panel of laboratory parameters associated with the risk of atherosclerosis were studied in 192 patients with histologically-verified breast carcinoma., Results: Patients with metastatic disease had significantly higher fibrinogen, C-reactive protein (CRP), urinary neopterin and mean IMT, and significantly lower serum albumin and hemoglobin concentrations. Significant correlations were observed between CRP, urinary neopterin, mean IMT and other parameters of cardiovascular risk. Age was an independent predictor of the presence of sonographic signs of atherosclerosis using logistic regression, and age, glucose, time from start of chemotherapy, high-density lipoprotein cholesterol, D-dimers were independently associated with IMT in stepwise regression models., Conclusion: In addition to the associations between IMT and laboratory or clinical parameters of the risk of atherosclerosis, IMT may also be associated with the time from chemotherapy.

The production of secondary metabolites in Trifolium pratense L. suspension culture of the family of legume plants (Fabaceae) is low, and therefore there was an attempt to increase it by elicitation. New synthetic substance, 2-(2-fluoro-6-nitrobenzylsulfanyl)pyridine-4-carbothioamide, was tested as elicitor--a substance that showed the best elicitation effect after 48-hour application of 1 μmol L⁻¹ concentration. Maximum contents of genistin (11.60 mg g⁻¹ DW), daidzein (8.31 mg g⁻¹ DW), and genistein (1.50 mg g⁻¹ DW) were recorded, and the production of these isoflavonoids thus significantly increased, when compared with the control, by 152%, 151%, and 400%. The maximum content of flavonoids (5.78 mg g⁻¹ DW) and the increase in the production by 142%, when compared with the control, were induced by 6-hour application of 100 μmol L⁻¹ concentration. The tested substance showed to be an effective elicitor of phenylpropane metabolism.

Variations in total phenolic and flavonoid contents as well as antioxidant activity of Bellis perennis (common daisy) flowers were investigated. The flowers were collected monthly (from March to October, i.e., during the usual flowering season of the plant) at three localities in three different years. Total flavonoids were determined spectrophotometrically by two methods: by formation of a complex with aluminium chloride after acidic hydrolysis of flower extracts (method 1) and by reaction with boric and oxalic acids in extracts without their modification (method 2). Total phenolics were determined spectrophotometrically using the Folin-Ciocalteu reagent. The antioxidant activity was determined spectrophotometrically by a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. The contents of flavonoids varied from 0.31 to 0.44 mg quercetin equivalent/100 mg dry weight (method 1) and from 1.37 to 2.20 mg pigenin-7-glucoside equivalent/100 mg dry weight (method 2). Total phenolics ranged from 2.81 to 3.57 mg gallic acid equivalent/100 mg dry weight. The antioxidant activity expressed as IC(50) values varied from 66.03 to 89.27 µg/mL; it is about 50, 30, 20, and 10 times lower as compared with quercetin, ascorbic acid, Trolox®, and butylhydroxytoluene, respectively, and about five times higher in comparison with apigenin-7-glucoside. There is a significant correlation between antioxidant activity and total phenolics. No correlation between total flavonoid contents and antioxidant activity was observed. Contents of phenolics and flavonoids as well as antioxidant activity of daisy flowers vary to a relatively small extent during the year and are not dependant on the time of collection. Thus, the flowers possess comparable quality as to these characteristics over the whole flowering season of Bellis perennis. Effects of environmental factors on the amounts of secondary metabolites in plants are also discussed.

Administration of imatinib is the therapy of choice in patients with advanced (inoperable) or metastatic gastrointestinal stromal tumors (GIST). Gastrointestinal toxicity is one of the most common side effects of anticancer therapy, including imatinib. Measurement of intestinal permeability represents a method of noninvasive laboratory assessment of gastrointestinal toxicity. We have measured intestinal permeability (by determining absorption of lactulose, mannitol and xylose), vitamin A absorption and serum alpha-tocopherol in 16 patients with advanced/metastatic GIST treated with imatinib. Lactulose/mannitol and lactulose/xylose ratios as well as parameters of vitamin A absorption did not change significantly during the treatment, but a significant decrease of alpha-tocopherol was observed. We conclude that, in contrast to most other anticancer agents studied so far, imatinib does not have an effect on intestinal permeability. No effect on vitamin A absorption was observed, but serum alpha-tocopherol decreased significantly during the treatment.