Hypericum alpestre extract exhibits in vitro and in vivo anticancer properties by regulating the cellular antioxidant system and metabolic pathway of L-arginine.

Conventional treatment methods are not effective enough to fight the rapid increase in cancer cases. The interest is increasing in the investigation of herbal sources for the development of new anticancer therapeutics. This study aims to investigate the antitumor capacity of Hypericum alpestre (H. alpestre) extract in vitro and in vivo, either alone or in combination with the inhibitors of the  l-arginine/polyamine/nitric oxide (NO) pathway, and to characterize its active phytochemicals using advanced chromatographic techniques. Our previous reports suggest beneficial effects of the arginase inhibitor NG-hydroxy-nor- l-arginine and NO inhibitor NG-nitro-Larginine methyl ester in the treatment of breast cancer via downregulation of polyamine and NO synthesis. Here, the antitumor properties of H. alpestre and its combinations were explored in vivo, in a rat model of mammary gland carcinogenesis induced by subcutaneous injection of 7,12-dimethylbenz[a]anthracene. The study revealed strong antiradical activity of H. alpestre aerial part extract in chemical (DPPH/ABTS) tests. In the in vitro antioxidant activity test, the H. alpestre extract demonstrated pro-oxidant characteristics in human colorectal (HT29) cells, which were contingent upon the hemostatic condition of the cells. The H. alpestre extract expressed a cytotoxic effect on HT29 and breast cancer (MCF-7) cells measured by the MTT test. According to comet assay results, H. alpestre extract did not exhibit genotoxic activity nor possessed antigenotoxic properties in HT29 cells. Overall, 233 substances have been identified and annotated in H. alpestre extract using the LC-Q-Orbitrap HRMS system. In vivo experiments using rat breast cancer models revealed that the H. alpestre extract activated the antioxidant enzymes in the liver, brain, and tumors. H. alpestre combined with chemotherapeutic agents attenuated cancer-like histological alterations and showed significant reductions in tumor blood vessel area. Thus, either alone or in combination with Nω -OH-nor- l-arginine and Nω -nitro- l-arginine methyl ester, H. alpestre extract exhibits pro- and antioxidant, antiangiogenic, and cytotoxic effects.

The Interplay between Endogenous and Foodborne Pro-Oxidants and Antioxidants in Shaping Redox Homeostasis.

Oxidative stress has been known about in biological sciences for several decades; however, the understanding of this concept has evolved greatly since its foundation. Over the past years, reactive oxygen species, once viewed as solely deleterious, have become recognized as intrinsic components of life. In contrast, antioxidants, initially believed to be cure-all remedies, have failed to prove their efficacy in clinical trials. Fortunately, research on the health-promoting properties of antioxidants has been ongoing. Subsequent years showed that the former assumption that all antioxidants acted similarly was greatly oversimplified. Redox-active compounds differ in their chemical structures, electrochemical properties, mechanisms of action, and bioavailability; therefore, their efficacy in protecting against oxidative stress also varies. In this review, we discuss the changing perception of oxidative stress and its sources, emphasizing everyday-life exposures, particularly those of dietary origin. Finally, we posit that a better understanding of the physicochemical properties and biological outcomes of antioxidants is crucial to fully utilize their beneficial impact on health.

Relationship between Chemical Structure and Biological Activity Evaluated In Vitro for Six Anthocyanidins Most Commonly Occurring in Edible Plants.

Numerous studies have provided evidence that diets rich in anthocyanins show a broad spectrum of health benefits. Anthocyanins in nature are usually found in the form of glycosides. Their aglycone forms are called anthocyanidins. The chemical structure of anthocyanins is based on the flavylium cation, but they differ in the position and number of substituents. However, the bioactives and foods that contain them are frequently treated as a uniform group of compounds exhibiting the same biological activity, without paying attention to the structural differences between individual anthocyanidins. The aim of this study was to find out how structural differences impact the biological activity of the six most common dietary anthocyanidins, i.e., delphinidin (Dp), petunidin (Pt), cyanidin (Cd), malvidin (Mv), pelargonidin (Pg) and peonidin (Po). The study concentrated on redox-related phenomena and compared the following parameters: antioxidant activity (measured using various methods: spectrophotometric tests (ABTS, DPPH), ORAC assay and CAA test (cellular antioxidant activity)), the ability to inhibit growth of human colon cancer cells (HT29; determined using MTT assay), and the ability of studied compounds to protect DNA from oxidative damage (comet assay). Based on the obtained results, the relationship between the structure of studied anthocyanidins and their biological activity was assessed. The obtained results revealed that the number and position of the hydroxyl and methoxy groups in the anthocyanidin structure strongly influenced not only the color of anthocyanidins but most of all their antioxidant and biological activities.

Post-Chromatographic Derivatization Coupled with Mass Spectrometry as a Method of Profiling and Identification of Antioxidants; Ligustrum vulgare Phytocomplex as an Example.

High-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) coupled with radical scavenging assays, such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) can be both used for the detection of the antioxidants in plant extracts. In this study, the ethanolic (70% v/v) extracts from different morphological parts of Ligustrum vulgare collected at different stages of maturity were used as the source of antioxidants. The final identification of antioxidants was performed using high-resolution mass spectroscopy (HRMS). As a result, 19 compounds with antioxidant properties detected with HPLC-ABTS assay and 10 compounds detected with HPTLC-DPPH/ABTS assay were identified, mostly from the group of iridoids, phenylethanoids, and flavonoids. When comparing different L. vulgare samples, it was found that the extracts obtained from leaves contained the greatest number of antioxidants. The results of this study suggest that HPTLC-DPPH/ABTS as well as HPLC-ABTS derivatization coupled with the HRMS can be successfully used for profiling and identification of antioxidants from natural sources. Planar chromatography is more suitable for screening multiple samples because of its simplicity, whereas more challenging liquid chromatography provides more detailed information and is therefore better for a selected set of samples.

Comparative Study on Assisted Solvent Extraction Techniques for the Extraction of Biologically Active Compounds from Sideritis raeseri and Sideritis scardica.

The plants in the Sideritis genus are postulated to exhibit several important medicinal properties due to their unique chemical composition. To isolate the targeted phytochemical compounds, the selection of a suitable extraction method is of primary importance. In this work, a comparative study on the phytochemical profiles of various Sideritis raeseri and Sideritis scardica extracts has been carried out. An untargeted metabolomics approach based on ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry was applied to investigate the metabolic differences between extracts obtained by conventional extraction and extractions assisted by microwaves, ultrasounds and high pressure. Additionally, the influence of extraction solvents on HPLC antioxidant profiles obtained following the derivatization of analytes with ABTS reagent was evaluated. A total of 102 metabolites have been putatively identified. The major secondary metabolites groups were classified as flavonoids, terpenoids, phenylethanoid glycosides and phenolic acids. The main antioxidants in the extracts were isoscutellarein and hypolaetin derivatives as well as verbascoside and chlorogenic acid. The results showed that 70% ethanol was the most effective extractant for different classes of phytochemicals including antioxidants. In addition, extraction supported with microwaves, ultrasounds or high pressure improved the overall recovery of metabolites by about 3 times compared to the conventional extraction method.

Effects of Post-Harvest Elicitor Treatments with Ultrasound, UV- and Photosynthetic Active Radiation on Polyphenols, Glucosinolates and Antioxidant Activity in a Waste Fraction of White Cabbage (Brassica oleracea var. capitata).

Biosynthesis of phytochemicals in leaves of Brassica can be initiated by abiotic factors. The aim of the study was to investigate elicitor treatments to add value to waste of cabbage. A leaf waste fraction from industrial trimming of head cabbage was exposed to UV radiation (250-400 nm, 59 and 99 kJ∙m-2, respectively), photosynthetic active radiation (PAR, 400-700 nm, 497 kJ∙m-2), and ultrasound in water bath (35 kHz, at 15, 30 and 61 kJ∙l-1 water), in order to improve nutraceutical concentration. UV was more effective than PAR to increase the level of flavonols (2 to 3-fold higher) and hydroxycinnamate monosaccharides (1 to 10-fold higher). PAR was three times as effective as UV to increase anthocyanins. Interaction of PAR + UV increased antioxidant activity (30%), the content of five phenolics (1.4 to 10-fold higher), and hydroxycinnamic monosaccharides (compared with PAR or UV alone). Indoles were reduced (40-52%) by UV, but the other glucosinolates (GLS) were unaffected. Ultrasound did not influence any parameters. The results are important for white cabbage by-products by demonstrating that UV + PAR can be successfully used as an effectual tool to increase important phenolics and antioxidant activity of waste fraction leaves without an adverse effect on the main GLS.

Natural Products Counteracting Cardiotoxicity during Cancer Chemotherapy: The Special Case of Doxorubicin, a Comprehensive Review.

Cardiotoxicity is a frequent undesirable phenomenon observed during oncological treatment that limits the therapeutic dose of antitumor drugs and thus may decrease the effectiveness of cancer eradication. Almost all antitumor drugs exhibit toxic properties towards cardiac muscle. One of the underlying causes of cardiotoxicity is the stimulation of oxidative stress by chemotherapy. This suggests that an appropriately designed diet or dietary supplements based on edible plants rich in antioxidants could decrease the toxicity of antitumor drugs and diminish the risk of cardiac failure. This comprehensive review compares the cardioprotective efficacy of edible plant extracts and foodborne phytochemicals whose beneficial activity was demonstrated in various models in vivo and in vitro. The studies selected for this review concentrated on a therapy frequently applied in cancer, anthracycline antibiotic-doxorubicin-as the oxidative stress- and cardiotoxicity-inducing agent.

The comparison of betalain composition and chosen biological activities for differently pigmented prickly pear (Opuntia ficus-indica) and beetroot (Beta vulgaris) varieties.

Betalains are a group of plant originated pigments with chemopreventive potential. The aim of this study was to relate the composition of betalains and chosen biological activities (antioxidant, cytotoxic, anti-genotoxic and influence on enzymatic activities) for extracts from differently pigmented varieties of prickly pear (yellow, orange and red) and beetroot (white and red). The assumption was that phytocomplexes of tested varieties of the same plant species would exhibit generally similar chemical composition differing mostly in betalain content, which will be reflected by their biological activity. Betalain composition analysis and antioxidant profiles confirmed that the content and composition of these pigments is strongly correlated with the antioxidant activity of tested plant extracts measured by spectrophotometric methods and CAA test. However, the results of determinations of other biological activities showed that in the case of actual plant foods, there was no simple relationship between betalain content or composition and chemopreventive potential.

Phytochemical composition and biological activities of differently pigmented cabbage (Brassica oleracea var. capitata) and cauliflower (Brassica oleracea var. botrytis) varieties.

BACKGROUND: Brassica plants contain a wide spectrum of bioactive components that are responsible for their health-promoting potential such as vitamins, polyphenols and glucosinolates. This study attempted to relate the composition of bioactive phytochemicals and chosen biological activities (antioxidant, cytotoxic, anti-genotoxic, and influence on enzymatic activities) for extracts from differently pigmented cabbage (white and red) and cauliflower (white and purple) varieties. The assumption was that tested varieties of the same plant would exhibit similar chemical composition differing mostly in anthocyanin content and that the latter will be reflected in biological activity. RESULTS: Profiles of antioxidants obtained using post-column derivatization with ABTS radical confirmed, that the content and composition of anthocyanins is strongly correlated with the antioxidant capacity of tested plant extracts measured by spectrophotometric methods (ABTS, FC, DPPH, FRAP), and Cellular Antioxidant Activity (CAA) test. The results of determinations of other biological activities showed that opposite to purified bioactive phytochemicals, in the case of actual plant foods, there was no simple relationship between anthocyanin content and chemopreventive potential. CONCLUSION: Obtained results suggest that there must be some kind of interaction between different phytochemicals, which decides on the final health promoting activity of edible plants as suggested by for example the food synergy concept. © 2019 Society of Chemical Industry.

The influence of plant protection by effective microorganisms on the content of bioactive phytochemicals in apples.

BACKGROUND: The phytochemicals of two apple cultivars (Yellow Transparent and Early Geneva) protected in two ways, conventionally with chemical pesticides or by effective microorganisms (EM), were compared. Two types of components were determined: lipids synthesised constitutively and generated via inducible pathways polyphenols along with antioxidant activity and profiles. RESULTS: The antioxidant activities assessed with ABTS, DPPH and Folin-Ciocalteu reagents were about two-fold higher in the case of microbiologically protected apples. The qualitative composition of phenolics determined by LC-DAD-MS varied between cultivars and the part of apples studied, while the method of protection caused mainly differences in concentration of some groups of polyphenols (hydroxycinnamates, flavanols, dihydrochalcones, flavonols, anthocyanins). The apples from biological cultivation contained about 34-54% more phenolics than these from a conventional orchard. In contrast, lipid composition did not differ significantly between apples originating from conventional and bio-crops. CONCLUSION: The results indicate that the advantage of using the EM technology in agriculture may not only be the reduction of consumption of chemical fertilisers and synthetic pesticides, but also, at least in the case of apples, may lead to the production of crops with improved health quality due to the higher content of bioactive phytochemicals. © 2017 Society of Chemical Industry.

Determination of antioxidantactivity of phytochemicals in cellular models by fluorescence/luminescence methods.

As soon as the role of Reactive Oxygen Species (ROS) in so-called civilization diseases, which include non-infectious chronic diseases such as cancer, diabetes or high blood pressure has been discovered, and the possibility of employing antioxidants as a remedy for these diseases have been proposed, scientists developed a broad spectrum of methods to determine antioxidant activity of pure chemicals and plant extracts, as well as dietary supplements. Most of these methods are based on simple redox reactions between antioxidant and ROS (for example ABTS, DPPH, or FRAP tests). However, chemical methods of assessing antioxidant activity are rarely biologically relevant. They do not mirror the real effect of antioxidants in living organisms, because they are used in non-physiological conditions of temperature and pH; neither they take metabolism nor intracellular transport under consideration. The perfect model for assessment of antioxidant activity in living organisms would be human or animal model, but such determinations are very complicated and often ambiguous. The current best alternative to chemical and human tests are assays employing cell culture models being less expensive than human tests, yet still reflecting biological systems more convincingly than chemical assays. Cellular antioxidant assays are performed under physiological pH and temperature, but most importantly, they take metabolism and intracellular transport under consideration. In this review, we present cellular tests used to determine antioxidant activity that are based on luminescence and fluorescence methods.

Phospholipids and products of their hydrolysis as dietary preventive factors for civilization diseases.

The results of numerous epidemiological studies indicate that phospholipids play an important role in the prevention of chronic diseases faced by contemporary society. Firstly, these compounds are responsible for the proper functioning of cell membranes, by ensuring liquidity and permeability, which is pivotal for normal activity of membrane proteins, including receptors. These mechanisms are at the core of prevention of cancer, autoimmune or neurological disorders. Secondly, structure and properties of phospholipids cause that they are highly available source of biologically active fatty acids. Thirdly, also products of endogenous hydrolysis of phospholipids exhibit biological activity. These include lysophospholipids formed as a result of disconnecting free fatty acid from glycerophospholipids in the reaction catalyzed by phospholipase A, phosphatidic acid and hydrophilic subunits released by the activity of phospholipase D. The bioactive products of hydrolysis also include ceramides liberated from phosphosphingolipids after removal of a hydrophilic unit catalyzed by sphingomyelinase. Phospholipids are supplied to the human body with food. A high content of phospholipids is characteristic for egg yolk, liver, pork and poultry, as well as some soy products. Particularly beneficial are phospholipids derived from seafood because they are a rich source of essential fatty acids of the n-3 family.

Antioxidant and antimicrobial properties of bioactive phytochemicals from cranberry.

In the rational human diet, the important role of fruits and vegetables, which are a source of bioactive phytochemicals, is emphasized. Among fruits particular attention, due to a number of documented health-promoting properties, is focused on cranberry. This fruit is characterized by the high content of antioxidant phenolic compounds, which may support the natural antioxidant defense system of the body in the prevention of damage caused by oxidative stress induced by reactive oxygen species (ROS). Therefore, cranberry is suggested for the prevention of civilization diseases such as atherosclerosis, hypertension and cancer, whose etiology is associated directly with oxidative stress. The health-promoting potential of cranberry is also associated with its antibacterial activity resulting from the presence of proanthocyanidins (PAC) type A with documented anti-adherence properties. The best-established medical applications of cranberry fruits are prevention and treatment of bacterial infections of the urinary tract (UTI), infections of gastric mucosa, and infections of the oral cavity. Due to the widespread use of cranberry and pharmaceutical preparations containing PACs in treating UTI, it is very important to evaluate the absorption, bioavailability and metabolism of these compounds in the human body.

Cabbage Juices and Indoles Modulate the Expression Profile of AhR, ERα, and Nrf2 in Human Breast Cell Lines.

Our previous studies showed the diversified effect of cabbage juices and indoles on the estrogen metabolism key enzymes (CYP1A1, CYP1A2, CYP1B1) in breast epithelial cells differing in ER status, i.e., in tumorigenic-MCF7, MDA-MB-231 and non-tumorigenic-MCF10A cells. The aim of the present study was to further investigate the mechanism of chemopreventive action of cabbage juice and its active components by evaluating their effect on the expression of AhR, ERα, and Nrf2 using the same treatment regimen. The mRNA level of AhR and ERα was changed in a cell type-dependent manner and in general correlated with previously observed modulation of CYP expression. However, in most cases the alterations in mRNA were not accompanied by the changes in the level of relevant proteins. Marked differences were also found in the effect of cabbage juices and indoles; although both cabbage juices and indoles increased most of the NQO1 transcript levels in all tested lines, indoles also enhanced GSTP transcription in MCF7 and MDA-MB-231. Overall, the results of this study partly explain the mechanism behind the chemopreventive activity of white cabbage products and indicate that modulation of the expression of specific transcription factors may play an important role in this process.

The influence of roasting and additional processing on the content of bioactive components in special purpose coffees.

ABSTRACT: Coffee being the beverage consumed worldwide is also a very competitive commodity. Consequently, producers seek ways of attracting consumers by proposing e.g. novel ingredient combinations usually without evaluating their health quality. In this study, variations in health-promoting determinants for five special purpose coffee brews were characterized. The major bioactive components - chlorogenic acids (CAs) - detected by HPLC-DAD-MS included caffeoyl-, feruloyl- and dicaffeoylquinic acids. Roasting declined CAs content by 50 %, while caffeine content increased by about 30 % during this process. In roasted coffee brews studied, CAs content varied from 14.1 to 26.6 mg/g; smaller variations were seen in antioxidant potential (determined by spectrophotometric and cyclic voltammetry assays). Profiles generated by HPLC with post-column on-line antioxidant detection revealed that caffeoylquinic acids were the most abundant antioxidants in samples studied. The highest antioxidative potential exhibited coffee enriched with green coffee extract confirming the soundness of such an approach to obtain healthier products. HIGHLIGHTS: • Special purpose coffees are equivalent to regular ones as regards antioxidant potential. • Caffeoylquinic acids are the most abundant antioxidants in coffee samples studied. • Roasting process causes some degradation of chlorogenic acids but not caffeine. • Special purpose coffees retain health benefits while being more attractive to consumers.

The influence of selenium addition during germination of Brassica seeds on health-promoting potential of sprouts.

The correlation among selenium uptake, the content of bioactive compounds in sprouts, and biological activities triggered in cultured human cells by sprout extracts was investigated. Seeds of Brassica crops and rye were treated with SeO2 water solution. The selenium levels in sprouts increased from 1.0-4.1 to 53.3-382 µg/g dw with no influence on plant physiology according to the indices used. Neither the composition of glucosinolates (GL) in Brassica sprouts nor the myrosinase activity nor the composition of GL breakdown lipophilic products were significantly affected. In all Brassica sprouts, conversion to health-promoting isothiocyanates (ITC) and indoles corresponded to only 1% of total GLs. Low ITC concentration may explain observed lack of induction of glutathione S-transferases (GST) and quinone oxidoreductase (NQO) detoxifying enzymes in HT29 cells exposed to sprout extracts. The insignificant impact on cell growth and genome function suggests that Brassica sprouts may be safe vehicle of selenium to combat its dietary deficiency.

Causes of late diagnosis of the reproductive organs' cancer in the opinion of suffering women from urban and rural areas of Lublin as an indicator of the condition of the early cancer detection system: a preliminary report.

INTRODUCTION: Tumours as well as the cardiovascular diseases are the leading causes of deaths in Poland. This article contains excerpts from research on complex causes of late diagnosis of cancer among the region's residents. AIM OF THE STUDY: One of the specific aims of the research undertaken was to learn about subjective assessment of women suffering from cancer taking into account its late diagnosis. MATERIAL AND METHODS: The research was conducted on 130 women with diagnosed cancer of reproductive organs in the late stage of the disease, who were in oncological care. The method of diagnostic survey in the form of a questionnaire was developed for the study. RESULTS: The research reveals that the place of living has an impact on the opinions of suffering women as for the causes of late diagnosis of cancer and, secondly, that their oncological awareness is low. CONCLUSIONS: In the examined group, cancer awareness of women already having cancers - irrespective of the environment of settling, was low and did not constitute the grounds for taking pro-health decisions in the area of the early diagnostic testing of cancer. This fully confirms the need for the research on effective tools to increase the awareness, particularly in the population of healthy persons, including menopausal and postmenopausal women.The opinions indirectly indicate a weaker organization and effectiveness of the activities of the cancer prevention programs in the country than those organized in the city.

Modulation of CYP19 expression by cabbage juices and their active components: indole-3-carbinol and 3,3'-diindolylmethene in human breast epithelial cell lines.

PURPOSE: The aim of this study was to evaluate the effect of white cabbage and sauerkraut juices of different origin and indole-3-carbinol (I3C) and diindolylmethane (DIM) on expression of CYP19 gene encoding aromatase, the key enzyme of estrogen synthesis. METHODS: Human breast cell lines (MCF7, MDA-MB-231 and MCF10A) were examined to compare the action of cabbage juices versus their active components (I3C, DIM). Real-time PCR and Western blot were used in order to analyse CYP19 mRNA and protein, respectively. RESULTS: Remarkable differences in the effect on CYP19 transcript and protein level were found between the cabbage juices (in 2.5-25 mL/L concentrations) and indoles (in 2.5-50 µM doses) in the three cell lines. While cabbage juices at the lower doses diminished the aromatase expression in nontumorigenic/immortalized MCF10A breast cells (0.25-0.86-fold change, P < 0.05), I3C and DIM were more efficient in decreasing the aromatase expression in estrogen-dependant MCF7 breast cancer cells (0.24-0.82-fold change, P < 0.05). Inhibition of aromatase by juice obtained from cabbage grown on industrial farm was correlated with the induction of apoptosis (1.7-1.8-fold change, P < 0.01) in MCF10A cells. In estrogen-independent MDA-MB-231 cells, up-regulation of CYP19 expression by I3C and DIM (1.5-2.0-fold change, P < 0.05) was observed. Similarly, in MCF7 cells juices increased aromatase expression (1.1-2.2-fold change, P < 0.05). CONCLUSION: These results, particularly that obtained in nontumorigenic/immortalized MCF10A cells, suggest that chemopreventive activity of cabbage against breast cancer observed in epidemiological studies may be partly explained by inhibition of the aromatase expression.

LC-MS/MS Determination of Isoprostanes in Plasma Samples Collected from Mice Exposed to Doxorubicin or Tert-Butyl Hydroperoxide.

Isoprostanes are stable products of arachidonic acid peroxidation and are regarded as the most reliable markers of oxidative stress in vivo. Here we describe the LC-MS/MS procedure enabling simultaneous determination of four regioisomers (8-iso prostaglandin F2α, 8-iso-15(R)-prostaglandin F2α, 11ß-prostaglandin F2α, 15(R)-prostaglandin F2α) in plasma samples collected from mice. The four plasma isoprostanes are determined by LC-ESI-MS/MS with deuterated 8-iso-PGF2α-d4 as an internal standard (I.S.). For plasma samples spiked with the isoprostanes at a level of 200 pg/mL each, the method imprecision has been below 7.1% and mean inaccuracy equaled 8.7%. The applicability of the proposed approach has been verified by the assessment of changes in isoprostane levels in plasma samples derived from mice exposed to tert-butyl hydroperoxide (TBHP), a model inducer of oxidative stress, or to antitumor drug doxorubicin (DOX) known for potent stimulation of redox cycling. Compared to the control group of mice, both oxidative stress inducers tested increased the levels of three out of four isoprostanes in exposed animals; 11ß-prostaglandin F2α being the exception. The greatest rise was observed in the case of 15(R)-prostaglandin F2α, by about 50% and 70% in plasma samples derived from mice exposed to DOX and TBHP, respectively.

Selected problems associated with the treatment and care for patients with colostomy - part 2.

Generally, ostomy is a purposeful connection of the lumen of the intestine with abdominal integuments by surgery. The study presents practical solutions related to care for the colostomy patient, i.e. an ostomy on the large intestine. The following issues will be discussed: regulating the defecation cycle, risk connected with improper selection of ostomy equipment, instruction on colostomy irrigation with practical advice and irrigation equipment supply. The knowledge of these rules and mastering them in practice is to provide ostomy patients not only with highest-standard care and help but also to prepare them for dealing with problems independently, i.e. for self-care.