Study of edge detection task in dental panoramic radiographs.

The purpose of this study is (1) to introduce a new approach for edge detection in orthopantograms (OPGs) and an improved automatic parameter selector for common edge detectors, (2) to present a comparison between our novel approach with common edge detectors and (3) to provide faster outputs without compromising quality. A new approach for edge detection based on statistical measures was introduced: (1) a set of N edge detection results is calculated from a given input image and a selected type of edge detector, (2) N correspondence maps are constructed from N edge detection results, (3) probabilities and average probabilities are computed, (4) an overall correspondence is evaluated for each correspondence map and (5) the correspondence map providing the best overall correspondence is taken as the result of edge detection procedure. A comparison with common edge detectors (the Roberts, Prewitt, Sobel, Laplacian of the Gaussian and Canny methods) with various parameter settings (304 combinations for each test image) was carried out. The methods were assessed objectively [edge mismatch error (EME), modified Hausdorff distance (MHD) and principal component analysis] and subjectively by experts in dentistry and based on time demands. The suitability of the new approach for edge detection in OPGs was confirmed by experts. The current conventional methods in edge detection in OPGs are inadequate (none of the tested methods reach an EME value or MHD value below 0.1). Our proposed approach for edge detection shows promising potential for its implementation in clinical dentistry. It enhances the accuracy of OPG interpretation and advances diagnosis and treatment planning.

Prognostic significance of increased urinary neopterin concentrations in patients with breast carcinoma.

Increased serum or urinary concentrations of neopterin have been described in patients with tumors of different primary locations, but reports on neopterin in patients with breast carcinoma are relatively innumerous. We have evaluated urinary neopterin in 456 patients with breast carcinoma. Urinary neopterin was determined using high-performance liquid chromatography. Neopterin in patients was increased only in a minority of patients with breast carcinoma. Increased urinary neopterin was associated with inferior overall survival. Prognostic significance of increased urinary neopterin was evident in patients with tumors expressing hormone receptors or/and human epidermal growth factor receptor (HER)-2, but not in patients with triple negative tumors. Among other parameters determined, C-reactive protein, hemoglobin, peripheral blood neutrophil count and platelet count were significant prognostic factors. On multivariate analysis, age, expression of hormone receptors, neutrophils, stage and hemoglobin concentration were independent prognostic indicators. In conclusion, serum neopterin is increased only in a minority of patients with breast carcinoma. Increased urinary neopterin was predictive of poor survival in univariate, but not multivariate analysis. Age, expression of hormone receptors, neutrophils, stage and hemoglobin concentration were independent prognostic indicators.

The importance of rheological parameters in the therapy of microcirculatory disorders.

Rheological conditions basically influence tissue perfusion, oxygen and nutrient supply, tissue regeneration and in its consequence the course of pathological processes, especially in microcirculation and partially even in macrocirculation. Haemorheotherapy has shown to be successful in several indications (critical disorders in microcirculation) when other methods of therapy have failed. In this study we describe the changes of effectivity indicators in haemorheopheresis treatment and their clinical importance in cases of eye microcirculation, statoacoustic apparatus and disorders of the lower extremities. We treated with haemorheopheresis (separator Cobe.Spetra + Evaflux filter) 24 patients (16 patients with age related macular degeneration, 5 with critical peripheral arterial foot disease, and 3 with acute hearing loss). After the procedures alpha2-macroglobulin decreases by about 58%, fibrinogen by about 69%, IgM by about 61%, LDL-cholesterol by about 77%, apolipoprotein B by about 76% and lipoprotein(a) by about 63%. It corresponds with a decrease in blood and plasma viscosity and clinical improvement in the observed patients, i.e. visual improvement, acceleration of tissue defect healing and improvement in hearing. We noticed 7.1% clinically insignificant side-effects. The method of haemorheopheresis was safe. It led to improvement in patients' clinical condition in the above mentioned indications when other methods of treatment failed.

Biotic elicitation of the Trifolium pratense L. suspension culture.

The important substances of secondary metabolism include flavonoids and isoflavonoids. The Trifolium pratense L. (Fabaceae) suspension culture's yield of these metabolites is low, thus an attempt was made to increase the production by elicitation. The endogenous signal substances of the plants' defensive responses include jasmonic acid that also functions as a biotic elicitor in the case of exogenous application. In the experiment the authors monitored the impact of 4 different concentrations of jasmonic acid on the Trifolium pratense L. (variety DO-8 and variety DO-9) suspension culture's yield. The culture was cultivated in Gamborg medium to which 2 mg.l(-1) of 2,4-dichlorophenoxyacetic acid and 2 mg.l(-1) of 6-benzylaminopurine were added. The maximum increase in the production of flavonoids was achieved, when compared with the control samples, with both varieties of the 500 micromol concentration (DO-9, 6-hour application by 140%; DO-8, 24-hour application by 65%). The production of isoflavonoids (genistin, daidzein, genistein, and formononetine) was best stimulated in both varieties by the 50 micromol concentration (in the case of DO-9 variety, the 48-hour application increased the content of genistin by up to 845%).

Effects of auxins on growth and scopoletin accumulation in cell suspension cultures of Angelica archangelica L.

Scopoletin is a coumarin possessing many interesting biological effects, e.g., spasmolytic, anti-inflammatory, antimutagenic, antioxidant, antifungal, apoptosis-inducing, antiproliferative, acetylcholinesterase-inhibitory, and hypouricemic activities. Plant tissue cultures represent a promising alternative source of valuable plant-derived substances. A number of physical and chemical factors influence the cell growth and secondary metabolite biosynthesis in plant tissue cultures. The mechanism of their action is not completely understood. Besides other factors, plant growth regulators and light conditions play an important role. Effects of four auxins (2,4-dichlorophenoxyacetic acid, 2,4-D, alpha-naphthaleneacetic acid, NAA, beta-indoleacetic acid, IAA or beta-indolebutyric acid, IBA) at four concentrations (0.2, 2, 10 or 20 mg/l) on the culture growth and accumulation of scopoletin in the medium were tested in Angelica archangelica cell suspension cultures cultured under continuous light or in the dark. The highest culture growth was achieved with 2 mg/l 2,4-D, and 10 mg/l IAA. The best scopoletin levels were obtained with 0.2 mg/l 2,4-D, 2 mg/l 2,4-D, 10 mg/l NAA, and 20 mg/l IAA. The effects of light conditions were less marked than those of auxins and their concentrations in influencing both the cell growth and scopoletin accumulation in Angelica archangelica cell suspension cultures. The changes brought about by auxins were modified by light conditions.

Abiotic elicitation of Trifolium pratense L. suspension culture.

Important substances of secondary metabolism include flavonoids and isoflavonoids. The Trifolium pratense L. (Fabacae) suspension culture is characterized by low production of these metabolites and therefore we tried to influence the production output with elicitation. From their origin point of view, the elicitors are divided into two groups - biotic and abiotic. The latter group includes, for instance, the salts of heavy metals. Our work was aimed at observing the effect of the copper sulphate abiotic elicitor on the production of the Trifolium pratense L. suspension culture (variety DO-8 and variety DO-9) that was cultivated in Gamborg media supplemented with 2 mg l(-1) of 2,4-dichlorophenoxyacetic acid and 2 mg l(-1) of 6-benzylaminopurine. The maximum increase in the flavonoid production took place, when compared with the test check, during the 168-hour application of the 100 micromol concentration. The DO-8 variety isoflavonoids production was stimulated namely during the 48-hour application of the I micromol concentration; the best elicitation effect of the DO-9 variety was achieved with the 168-hour application of the 10 micromol concentration.

[Effect of vanadium compounds on the growth and production of coumarins in the suspension culture of Angelica archangelica L]. / VIiv sloucenin vanadu na rust a produkci kumarinu v suspenzní kulture Angelica archangelica L.

Plant tissue cultures represent a promising source of substances of natural origin. The main problem of their use is a low production of the majority of secondary metabolites. One of the methods of increasing the production of these substances is elicitation, because the biosynthesis of many secondary metabolites in plant cells is part of the defensive reaction against biological or abiotic stress influences. The paper tested vanadium compounds as potential elicitors of the production of coumarins: sodium vanadate (0.2; 1; 10; 100 and 1000 microM/l of medium) and vanadyl sulfate (10; 20; 50; 100; 200 and 500 microM/l of medium). The toxicity of these substances for the culture was simultaneously monitored by means of the evaluation of the effects on growth (characterized by fresh and dry weights of biomass at the end of two-week cultivation). The cultures were grown both in the light and dark. The growth of the cultures was not influenced by sodium vanadate at concentrations of 0.2 to 100 microM. A vanadate concentration of 1000 microM acted already toxically (in comparison with the control culture, the fresh weight was decreased by 28 % and the dry weight by 41% when cultivated in the light; the fresh weight by 69% and the dry weight by 66% when cultivated in the dark). Vanadyl sulfate in concentrations of 10 to 50 microM did not affect the growth of the culture, at higher concentrations it decreased it gradually: a concentration of 500 microM acted already toxically, again more markedly when cultivated in the light (in comparison with the control culture, the fresh weight was decreased by 27% and dry weight by 38% when cultivated in the light; the fresh weight by 65% and the dry weight by 61% when cultivated in the dark). The production of coumarins was stimulated by sodium vanadate in a concentration of 0.2 and 1 microM when cultivated in the light. The content of coumarins increased in comparison with the control culture mainly in the medium by 46% and by 25% at vanadate concentrations of 0.2 and 1 microM, respectively. Vanadyl sulfate did not increase the production of coumarins.

[Explant culture of Trifolium pratense L]. / Explantátová kultura Trifolium pratense L.

The red cloverl seems to be a prospective source of flavonoids and isoflavonoids with phytoestrogenic activity. Young seedlings of four different varieties of Trifolium pratense L. were employed to derive callus and suspension cultures. The optimal medium for cultivation is Gamborg's cultivating medium with an addition of 2 mg x l(-1) of 2,4-dichlorphenoxyacetic acid and 2 mg x l(-1) of 6-benzylaminopurine. On the basis of growth and production characteristics, subcultivating intervals of 29 to 43 days in callus culture and 16 to 23 days in suspension culture were determined. TLC and HPLC revealed that the explant culture of Trifolium pratense L. contains the isoflavonoid formononetin.

[Effect of manganese (II), cobalt (II), and nickel (II) ions on the growth and production of coumarins in the suspension culture of Angelica archangelica L]. / Vliv manganatých, kobaltnatých a nikelnatých iontu na rust a produkci kumarinu v suspenzní kulture Angelica archangelica L.

The plant cell reacts to an increased concentration of metals in the environment by various mechanisms. They include an increase in the formation of heat-shock proteins, metallothioneins, phytochelatins, amino acids (cysteine, histidine), organic acids (citric, malic), or secondary metabolites. The latter mechanism is being investigated for its possible use in explant cultures for the stimulation of secondary metabolism, which is the source of substances of pharmaceutical importance. The study tested manganese (II) (0, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, and 50 mM in the medium), cobalt (II), and nickel (II) ions (0, 0.1, 0.5, 1, 5, 10, 50, 100, 200, and 500 microM in the medium) as potential elicitors of coumarin production. At the same time, toxicity of these metals for the culture was examined by evaluating their effect on growth (characterized by fresh and dry weight of biomass at the end of a two-week cultivation). Cultures were cultivated in the dark and in the light. It has been found that the growth of cultures is not influenced by manganese in concentrations ranging from 0 to 2 mM, then it slightly decreases, at a concentration of 50 mM it is lower by 20 % when cultivated in the dark and by 30 % when cultivated in the light in comparison with the control. Cobalt in concentrations of 0 to 50 microM does not significantly influence the growth of the culture, higher concentrations decrease the biomass yields, more markedly when cultivated in the light (at 500 microM Co by 60 %, in the dark only by 30 % in comparison with the controls). Nickel in concentrations of 0.1 to 200 microM does not influence growth, and in a concentration of 500 microM decreases it by approximately 30 % in comparison with the control both in the light and dark. Production of coumarins was not stimulated by any metal in comparison with the control cultures, only the removal of manganese from the medium in the culture cultivated in the dark increased production by about 15 % versus the control.

[Abiotic elicitation of the explant culture of Rheum palmatum L. by heavy metals]. / Abiotická elicitace explantátové kultury Rheum palmatum L. tezkými kovy.

Elicitation-produced stress activates the defensive reactions of the plant or plant explant, which result, among others, in a change in the transcription of the genes coding the enzymes influencing biosynthesis of secondary metabolites. The present paper investigated the effect of ions of heavy metals in concentrations od 1; 10, and 100 microM on the production of anthracene derivatives by the explant culture of Rheum palmatum L. cultivated on Murashige-Skoog medium with an addition of 10 mg.l(-1) of alpha-naphthylacetic acid. The periods of application of elicitation were 6; 24; 48, and 168 hours. It follows from the results that the applied abiotic elicitation positively influenced the production mainly in suspension culture. The maximal increase in the content of anthracene derivatives versus the control by 66% was observed after 48-hour action of 10 microM concentration of cadmium chloride. Aluminium chloride produced the largest increase in the production after 6-hour application of a 100 microM concentration, when in comparison with the control culture the production was stimulated by 60%.

[Effect of abiotic elicitation and calcium ions on production of explant cultures of Rheum palmatum L]. / Vliv abiotické elicitace a vápenatých iontu na produkci explantátové kultury Rheum palmatum L.

Elicitation is based on signal (elicitor)-induced expression of genes, which subsequently results in increased synthesis of secondary metabolities in plants and in vitro cultures. Elicitors do not usually influence gene activity directly but by means of transmitters of the signal, which include primarily calcium ions. The paper examined the effect of four concentrations of calcium ions on the production of anthracene derivatives by means of the callus and suspension cultures of Rheum palmatum L. (Polygonaceae), which was elicited by an abiotic elicitor--a 20 microM solution of lead dichloride. The culture was cultivated on a Murashige-Skoog medium with an addition of 10 mg.l-1 of alpha-naphthylacetic acid. It follows from the results that the maximal content of anthracene derivatives, determined by the photometric determination according to PhBs 4, was demonstrated in the suspension culture after 24-hr administration of the elicitor and a 10 mM calcium chloride solution. In comparison with the control and elicited groups, the production was stimulated by 44% and 17%, respectively. After an addition of calcium ions to the elicited callus culture, no positive influence on the production was observed.

[Effect of auxins on production of coumarin in a suspension culture of Angelica archangelica L]. / Vliv auxinu na produckci kumarinu v suspenzní kulture Angelica archangelica L.

The paper examined the effect of selected auxins (2,4-dichlorophenoxyacetic acid, alpha-naphthalene-acetic acid, beta-indoleacetic acid, beta-indoleburytic acid; each in four concentrations--0.2, 2, 10, and 20 mg/l) on the production of coumarins in the suspension culture of Angelica archangelica L. cultinated in the dark and under permanent lighting(3500 lux). The effect of the light regimen is, in comparison with auxins, less marked--the content of coumarins is mostly comparable both under permanent lighting and in the dark. The highest coumarin content was achieved with the use of alpha-naphthalene-acetic acid in a concentration of 0.2 mg/l with cultivation in the dark.

[Effect of jasminic acid on production of anthracene derivatives in cultures of Rheum palmatum L]. / Vliv kyseliny jasmínové na produkci anthracenových derivátu v kulture Rheum palmatum L. in vitro.

The process of elicitation makes use of the capacity of plants and plant cells cultivated in vitro to react to various stress stimuli by a number of protective reactions leading to increased accumulation of secondary metabolites. The endogenic signal substances of plant protective reactions include jasminic acid, which in the case of exogenous application also acts as an elicitor. The paper examined the effect of four concentrations of jasminic acid on the production of anthracene derivatives by a three-year-old tissue culture, which was derived from the roots of a two-year-old intact plant Rheum palmatum L. (Polygonaceae). The culture was cultivated on Murashige-Skoog medium with an addition of 10 mg.l-1 of alpha-naphthylacetic acid. The results show that the optimal effect of jasminic acid on the production of callus culture was manifested after a 12-hour application of the strongest concentration of 5 mM, and on the production of suspension culture after a 48-hour application of a concentration of 0.05 mM, when the photometric determination according to PhBs 4 demonstrated the maximal content of anthracene derivatives (1.26%) and the production was stimulated by 109% in comparison with the control.

[Seasonal changes in the hemolytic effects of the head of Bellis perennis L]. / Sezonní zmeny hemolytické úcinnosti úboru Bellis perennis L.

The drug Bellidis flos is used in therapy as a diuretic and an expectorant agent. Its principal constituents are saponins. The paper examined the haemolytic activity of the drug obtained by the collection of the capitula of Bellis perennis L. in a one month interval (from March to October) in the course of three years. The determination of haemolytic activity was carried out following the method of Pharmacopoea Bohemoslovaca IV. It has been found that the haemolytic activity of the drug changes in dependence on the time of collection of capitula during the year; it is lowest in March, then it increases, reaching the maximum in summer months (June, July, August), and then it decreases again.

[Effect of salicylic acid on production of anthracene derivatives in a culture of Rheum palmatum L. in vitro]. / Vliv kyseliny salicylové na produkci anthracenových derivátu v kulture Rheum palmatum L. in vitro.

Elicitation is a method making use of protective mechanisms of plants to increase the production of secondary metabolites in plants and cultures in vitro. Salicylic acid acts in plants as an inducer of the expression of protective proteins and it can be thus included into biotic elicitors. That is why the present paper examined the effects of five concentrations of salicylic acid on the production of anthracene derivatives by a three-year and a nine-year old culture derived from the root of the intact plant Rheum palmatum L. The culture was cultivated on Murashige-Skoog medium with an addition of 10 mg.l-1 of alpha-naphthylacetic acid. It follows from the results that increase in production after elicitation is higher in the three-year old culture than in the nine-year old one and elicitation of suspension culture is more successful than elicitation of callus culture. The maximal content of anthracene derivatives (1.418%), detected by a photometric essay according to PhBS 4, was demonstrated after a 48-hour action of 1 mM aqueous solution of salicylic acid, when production was increased by 101% in comparison with the control.

[Effect of precursors on the production of coumarins in a suspension culture of Angelica archangelica L]. / Vliv prekurzoru na produkci kumarinu v suspenzní kulture Angelica archangelica L.

The effect of potential precursors (cinnamic acid, phenylalanine, tyrosine) in three concentrations (0.01; 0.1; 1 mmol/l) on the growth of the culture and coumarin production was investigated in the suspension culture of Angelica archangelica L. The cultures were cultivated under constant illumination (3500 lux) and in the dark. The growth of the culture in the dark was not affected by the precursors, cinnamic acid in a concentration of 1 mmol/l exerted toxic action. The growth of the culture cultivated under constant illumination was stimulated by tyrosine in a concentration of 0.1 and 1 mmol/l, and phenylalanine in a concentration of 0.1 mmol/l; phenylalanine and cinnamic acid in a concentration of 1 mmol/l inhibited the growth of the culture. In the cultivation in the dark, coumarin production was increased by phenylalanine in a concentration 0.01 mmol/l and by tyrosine in a concentration of 1 mmol/l. In the cultivation under constant illumination, coumarin production was decreased by the action of cinnamic acid, was not affected by tyrosine, and phenylalanine (0.01 and 0.1 mmol/l) increased it in comparison with the culture without precursors.

[Effect of chitosan on the production of anthracene derivatives in tissue culture of Rheum palmatum L]. / Vliv chitosanu na produkci anthracenových derivátu v tkánové kulture Rheum palmatum L.

Explant cultures have been, besides other things, used for elicitation, which is an economically advantageous method making use of protective mechanism of plants to increase the production of secondary metabolites. The present study investigated the effect of 6, 12, 24, 48, 72, and 168 hours lasting action of four concentrations of the biotic elicitor chitosan on the production of anthracene derivatives by the callus and suspension culture of Rheum palmatum L. The culture was cultivated on a Murashige-Skoog medium with an addition of 10 mg.l-1 of alpha-naphthylacetic acid. A positive effect on the production was exerted in particular by elication of the suspension culture. The maximal content of anthracene derivatives (1.181%), found by photometric determination according to PhBs 4, as demonstrated after 24-hour action of a chitosan solution of a concentration of 1 mg/30 ml of the medium. In contrast to the suspension culture, the production of anthracene derivatives in the callus culture was influenced by elicitation only in the minimal way.

[Effect of the biotic elicitor, Candida utilis, on the production of anthracene derivatives in a tissue culture of Rheum palmatum L]. / Vliv biotického elicitoru Candida utilis na produkci anthracenových derivátu tkánovou kulturou Rheum palmatum L.

The paper studied the effect of the homogenate of Candida utilis on the production of anthracene derivatives by the callus and suspension culture of Rheum palmatum L. of different age and origin. The culture was cultivated on a Murashige-Skoog medium with an addition of 10 mg.l-1 of alpha-naphthylacetic acid. A positive effect on the production was caused mainly by the elicitation of the suspension culture. The maximal content of anthracene derivatives (1.346%), found by photometric determination according to PhBs 4, was demonstrated after 6-hour action of the homogenate of Candida utilis of a concentration of 0.143 mg/30 ml of the medium in an eight-year old culture derived from the root of the intact plant Rheum palmatum. A one-year-old culture derived from the root of the intact and germinating plant reacted to elicitation more sensitively as there was an increase in production up to 228% in comparison with the control. However, the content of anthracene derivatives was lower than in the eight-year-old culture. In contrast to the suspension culture, the production of anthracene derivatives in the callus culture was influenced by elicitation only in the minimal extent.

[Production of anthracene derivatives in elicited tissue cultures of Rheum palmatum L]. / Produkce anthracenových derivátu elicitovanou tkánovou kulturou Rheum palmatum L.

With a few exceptions, the characteristic problem of cultivation of plant explants in in vitro cultures is a low production of secondary metabolites by these cultures. One of the methods, which can achieve an increase in the production of natural substances in in vitro cultures, is elicitation of cell cultures. The effect of the biotic elicitor Pseudomonas aeruginosa in the form of a homogenate and an aqueous suspension of dead cells on the production of anthracene derivatives by the tissue culture of Rheum palmatum L. of different age and origin was examined. The culture was cultivated on a Murashige-Skoog medium with an addition of 10 mg.l-1 of alpha-naphthylacetic acid. The maximal content of anthracene derivatives found by photometric determination according to PhBs 4 was demonstrated in an eight years old culture (1.027%) after six hour elicitation with an aqueous suspension of dead cells of Pseudomonas aeruginosa (1.7 mg of dry matter/1 ml of solution). The culture newly derived from the root of the intact plant Rheum palmatum L. responded to elicitation more sensitively than the culture derived from the seed; nevertheless the content of anthracene derivatives was lower than in the eight years old culture.

[The effect of biotic elicitors on the production of flavonoids in suspension cultures of Bellis perennis L]. / Vliv biotických elicitoru na produkci flavonoidu v suspenzní kulture Bellis perennis L.

The effect of two biotic elicitors (homogenates of Pseudomonas aeruginosa and Candida utilis) in a suspension culture of Bellis perennis L. cultivated in the dark and day light period were examined. The growth of the culture was not negatively affected by the action of elicitors. Increased production of flavonoids in the culture depended on the sort, concentration and space of time of action of the elicitor, and on the manner of cultivation from the viewpoint of the light regimen. The best results were achieved with the use of the homogenate of Candida utilis after 24 hours in cultivation under the day light period and after 48 hours in cultivation in the dark.