DNA Methylation Changes Caused by Lawsone

Lawsone is a pigment that occurs naturally in plants. It has been used as a skin and hair dye for a long time. Moreover, its different biological activities have been reported. The present study focused on the effect of lawsone on a plant cell model represented by tobacco BY-2 cell suspension culture, which is used as a model comparable with the HeLa cells. It has been shown that lawsone inhibits the cell growth in the concentration-dependent manner. In addition, changes in DNA methylation level have been determined. We observed decreasing level of DNA methylation in the presence of increasing concentrations of lawsone. These results were accompanied with overproduction of reactive oxygen species (ROS). Since epigenetic modifications can be caused by different stress factors, there could be a connection between the changes in the level of DNA methylation and ROS production caused by lawsone

Využití lalokových plastik v operační léčbě dekubitů

Cíl: Cílem příspěvku je popsat operační léčbu dekubitů, která zahrnuje především pečlivou nekrektomii s kompletní exstirpací pseudocysty dekubitu, odstraněním píštělí a event. resekcí osteolytického nebo osteomyelitického ložiska. Soubor a metodika: Prezentován bude přístup k operační léčbě dekubitů vč. obrazové dokumentace, a to na konkrétním případu pa cienta (nar. 1974, paraplegik) s dekubitem, který byl ošetřen lalokovou plastikou. Závěr: Chirurgická léčba dekubitů zejména v první fázi vyžaduje multidisciplinární přístup. Poté je individuálně načasován a naplánován typ lalokové plastiky s ohledem na komorbidity pa cienta v závislosti na velikosti, hloubce a lokalizaci defektu. Antidekubitní prevence ve všech fázích léčby – předoperačně, perioperačně i pooperačně – významně snižuje riziko akutních i pozdních komplikací a recidivy dekubitů.Aim: Aim of the paper is to describe surgical treatment of pres sure ulcers, which includes primarily careful necrectomy with complete extirpation of ulcer’s pseudocyst, remov ing of fi stulas and eventual resection of osteolytic or osteomyelitic centre. Material and methods: This case report presents surgical procedure of pres sure ulcer treatment, includ ing photo documentation, in a paraplegic patient (born 1974) with pres sure ulcer treated by fl ap surgery. Conclusion: Surgical treatment of pres sure ulcer requires multidisciplinary approach, especial ly at the treatment onset. Type as well as tim ing of fl ap surgery is plan ned individual ly accord ing to patient’s commorbidities, based on size, depth and localisation of defect. Antidecubital prevention in all phases of treatment – before, dur ing and after the surgery – signifi cantly decreases risk of acute and late complications and pres sure ulcers recur rence. Autoři deklarují, že v souvislosti s předmětem studie nemají žádné komerční zájmy. The authors declare they have no potential confl icts of interest concerning drugs, products, or services used in the study. Redakční rada potvrzuje, že rukopis práce splnil ICMJE kritéria pro publikace zasílané do biomedicínských časopisů. The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers

Complexes of Silver(I) Ions and Silver Phosphate Nanoparticles with Hyaluronic Acid and/or Chitosan as Promising Antimicrobial Agents for Vascular Grafts

Polymers are currently widely used to replace a variety of natural materials with respect to their favourable physical and chemical properties, and due to their economic advantage. One of the most important branches of application of polymers is the production of different products for medical use. In this case, it is necessary to face a significant disadvantage of polymer products due to possible and very common colonization of the surface by various microorganisms that can pose a potential danger to the patient. One of the possible solutions is to prepare polymer with antibacterial/antimicrobial properties that is resistant to bacterial colonization. The aim of this study was to contribute to the development of antimicrobial polymeric material ideal for covering vascular implants with subsequent use in transplant surgery. Therefore, the complexes of polymeric substances (hyaluronic acid and chitosan) with silver nitrate or silver phosphate nanoparticles were created, and their effects on gram-positive bacterial culture of Staphylococcus aureus were monitored. Stages of formation of complexes of silver nitrate and silver phosphate nanoparticles with polymeric compounds were characterized using electrochemical and spectrophotometric methods. Furthermore, the antimicrobial activity of complexes was determined using the methods of determination of growth curves and zones of inhibition. The results of this study revealed that the complex of chitosan, with silver phosphate nanoparticles, was the most suitable in order to have an antibacterial effect on bacterial culture of Staphylococcus aureus. Formation of this complex was under way at low concentrations of chitosan. The results of electrochemical determination corresponded with the results of spectrophotometric methods and verified good interaction and formation of the complex. The complex has an outstanding antibacterial effect and this effect was of several orders higher compared to other investigated complexes

Effects of Various Doses of Selenite on Stinging Nettle (Urtica dioica L.)

The aim of this study was to investigate the effects of selenium (Se) on the growth, accumulation and possible mechanisms of Se transport in certain parts (roots, leaves, stamp and apex) of nettle (Urtica dioica L.) plants. Se was supplemented by one-shot and two repeated doses to the soil (2.0 and 4.0 mg Se per kg of substrate). Selenium content in roots increased linearly with dose and was significantly higher compared to other plant parts of interest. However, growth of the above-ground parts of plant as well as roots was slightly inhibited with increasing selenium concentration in comparison to the untreated plants. The content of phytochelatin2, a low molecular mass peptide containing a sulfhydryl group, correlated well with the Se content. This suggests a possible stimulation of synthesis of this plant peptide by Se

Flow injection analysis coupled with carbon electrodes as the tool for analysis of naphthoquinones with respect to their content and functions in biological samples

Naphthoquinones are one of the groups of secondary metabolites widespread in nature, where they mostly appear as chromatic pigments. They embody broad-range of biological actions from phytotoxic to fungicidal. An anticancer effect of naphthoquinones stimulates an interest in determination and characterization of single derivatives of 1,2- and 1,4-quinones in biological samples. The main aim of this work was to suggest a technique suitable to determine lawsone, juglone and/or plumbagin in biological samples and to study of their influence on BY-2 tobacco cells. The BY-2 tobacco cells were cultivated in the presence of the naphthoquinones of interest ( 500 mu g.l(-1)) for 24 h and then the morphological changes were observed. We found out that naphthoquinones triggered the programmed cell death at BY-2 cells, which can be confirmed by the apoptotic bodies in nucleus. After that we suggested and optimized different electrochemical techniques such differential pulse voltammetry ( DPV) coupled with hanging mercury drop ( HMDE) and carbon paste electrode, micro flow device coupled with carbon screen printed electrodes and flow injection analysis coupled with Coulochem III detector to determine them. The detection limits of naphthoquinones of interest were expressed as 3S/N and varied from units to hundreds of ng per millilitres according to methods used. Moreover, we utilized DPV coupled with HMDE and micro flow device to determine content of juglone in leaves Persian walnut ( Juglans regia). We determined that the leaves contained juglone tenths of g per 100 g of fresh weight. The results obtained show the convincing possibilities of using of these methods in analysis of plant secondary metabolites