Potential application of body fluids autofluorescence in the non-invasive diagnosis of endometrial cancer.

BACKGROUND: Endometrial carcinoma (EC) is the most common cancer of the female reproductive tract in developed countries. The prognosis and 5-year survival rates are closely tied to the stage diagnosis. Current routine diagnostic methods of EC are either lacking specificity or are uncomfortable, invasive and painful for the patient. As of now, the gold diagnostic standard is endometrial biopsy. Early and non-invasive diagnosis of EC requires the identification of new biomarkers of disease and a screening test applicable to routine laboratory diagnostics. The application of untargeted metabolomics combined with artificial intelligence and biostatistics tools has the potential to qualitatively and quantitatively represent the metabolome, but its introduction into routine diagnostics is currently unrealistic due to the financial, time and interpretation challenges. Fluorescence spectral analysis of body fluids utilizes autofluorescence of certain metabolites to define the composition of the metabolome under physiological conditions. PURPOSE: This review highlights the potential of fluorescence spectroscopy in the early detection of EC. Data obtained by three-dimensional fluorescence spectroscopy define the quantitative and qualitative composition of the complex fluorescent metabolome and are useful for identifying biochemical metabolic changes associated with endometrial carcinogenesis. Autofluorescence of biological fluids has the prospect of providing new molecular markers of EC. By integrating machine learning and artificial intelligence algorithms in the data analysis of the fluorescent metabolome, this technique has great potential to be implemented in routine laboratory diagnostics.

The gut microbiota, its relationship to the immune system, and possibilities of its modulation.

Research of the gut microbiota allows a better understanding of its composition and function and reveals the links between changes in the composition of bacteria and various intestinal but also systemic diseases. The gut microbiota performs several of important functions in the host body and influences many physiological processes. Gut bacteria synthesize many compounds needed for the proper function of the body (e.g., vitamins, short-chain fatty acids, and amino acids). They help maintain the integrity of the intestinal barrier and protect against pathogens. The gut microbiota plays a crucial role in the development and function of the immune system. Significant changes in the composition of the intestinal microbiota led to a dysbiotic state and the loss of its beneficial functions for humans. The review article summarizes the basic knowledge about the composition and function of the bacterial gut microbiota in healthy people, its role in the development of the immune system, and the mechanisms involved in maintaining homeostasis. It also presents current knowledge about the possibility of targeted modulation of the bacterial gut microbiota and faecal transplantation.

Correlation of selected serum protein levels with the degree of disability and NEDA-3 status in multiple sclerosis phenotypes.

OBJECTIVE: Multiple sclerosis (MS) is a multifactorial disease that begins in 80-85% of patients as a relapsing-remitting form (RRMS), and about 50% of patients gradually develop a secondary progressive form (SPMS). Approximately 10-20% of patients are affected primarily by the progressive form (PPMS) of this disease, which is characterised by a progressive course. This work focuses on the detection of potential protein biomarkers (CHI3L1, sNfL, CXCL13, MCP-1, MMP-2, and MMP-9) in the serum of patients with multiple sclerosis, divided according to phenotype. PATIENTS AND METHODS: We detected serum (RRMS: n=40, SPMS: n=25, PPMS: n=15) concentrations of selected markers of demyelination and inflammation using ELISA and zymographic determination for accurate and reproducible recognition of individual forms of MS, as well as a comparison of their levels with a worsening of no evidence of disease activity (NEDA-3) status and patients' disability. RESULTS: We detected that concentrations of sNfL in the blood of patients with PMS were higher than in those with RRMS (about 46%, p<0.001). The association with a worsening of NEDA-3 status was confirmed in the RRMS group by positive correlation of sNfL and the expanded disability status scale (EDSS) score (r=0.579, p<0.01). The levels of MCP-1 protein were not significantly different in patients with the RRMS to the progressive form of MS (r=0.58, p=0.02), while the levels of CHI3L1 in both the RRMS and PMS groups were significantly increased in groups with evidence of disease activity (RRMS about 76%, p<0.001 and PMS about 62%, p<0.001). CONCLUSIONS: Earlier and non-invasive detection of serum biomarkers and their correlations with neurological disability can help to recognise the transition from RRMS to progressive forms of MS and complement the results of clinical and radiological follow-up of the patient and potentially help in monitoring the patient's response to the treatment.

Insulin-like growth factor (IGF) system and hormonal-metabolic profile in women with polycystic ovary syndrome.

AIM of the study was to compare serum levels of IGF-1, IGF-2 and insulin­like growth factor­binding protein 3 (IGFBP-3) among non­obese and obese PCOS women, and to assess their relationship to metabolic and hormonal parameters.    METHODS: The study included 64 women diagnosed with PCOS (age 28.9 ± 5 years); 30 of them with BMI > 27 and 34 with BMI lower than 27. All subjects were examined for parameters of glucose and lipid metabolism, steroid hormones and serum IGF-1, IGF-2 and IGFBP-3 levels. RESULTS: No significant differences in serum IGFBP-3 (p=0.534), IGF-1 (p=0.29) and IGF-2 (p=0.56) between two groups have been detected. IGFBP-3 was in positive correlation with total cholesterol (p=0.026), LDL cholesterol (p=0.03) and triacylglycerols (p=0.022). IGF-1 were negatively correlated with insulin (p=0.022), HOMA IR (p=0.033), triacylglycerols (p=0.0196) and waist circumference (p=0.049). A positive correlation was detected between IGF-1 and HDL cholesterol (p=0.025). No significant relationship was observed between IGF-1 and steroid hormones. CONCLUSION: Serum levels of IGF-1, IGF-2 and IGFBP-3 in obese PCOS women do not differ from those detected in non­obese PCOS women. IGF-1 negatively correlated with metabolic parameters, indicating that lower IGF-1 may represent an important predictor of metabolic syndrome (MS) in PCOS women. All peptides seem to have little effect on ovarian steroidogenesis in PCOS (Tab. 1, Fig. 1, Ref. 30).

Is there a role for the IGF system and epidermal growth factor (EGF) in the pathogenesis of adrenocortical adenomas? A preliminary case-control study.

Adrenal incidentalomas (AI) are very common and mostly they are non-functioning adenomas (NFA). NFAs are often associated with insulin resistance and metabolic syndrome. Several biomarkers, including certain growth factors, may participatein the pathogenesis ofmetabolic changes in patients with adrenal adenomas.Patients with NFA and age-matched control subjects were enrolled in the study. Data on age, gender, presence of metabolic syndrome or its components were obtained for each subject. Blood samples were obtained and glycemia, insulinemia, lipid profile, and selected growth factor levels were measured. Forty-three patients with NFA and 40 controls were included in the study. Differences were not found in the metabolic syndrome and its components prevalence or in the biochemical profile between patients and the control group. Significant differences were noticed in the levels of IGF1, IGF2, and IGFBP3 (p=0.016, p=0.005, p=0.004, respectively), but there were no differences in VEGF or EGF concentrations. In NFA patients, an association between glycemia and EGF levels was present (p=0.026). No significant correlations between tumor size and insulin or growth factor concentrations were present in AI patients. Significantly higher serum IGF1, IGF2, and IGFBP3 concentrations in NFA patients may support the role of the IGF axis in the pathogenesis of adrenocortical lesions.No correlation between IGFs or IGFBP3 and parameters of glucose or lipid metabolism was found. Present results may support the role of the growth hormone axis rather than hyperinsulinemia and insulin resistance in the pathogenesis of adrenocortical adenomas.

Hypoxia factors suppression effect on the energy metabolism of a malignant melanoma cell SK-MEL-30.

OBJECTIVE: Malignant melanoma (MM), as well as other cancers, is a disorder in the cell life cycle at many levels. In terms of energy, the sync of cytosolic and mitochondrial metabolism is required for each cell. Mismatches also caused by hypoxic factors accumulate defects leading to the formation, development and invasiveness of malignant melanoma. Our aim was to compare the effect of HIF-1α and miR-210 on the metabolism of malignant melanoma cells in normoxia and pseudohypoxia. Further, we also investigated how gene silencing affects the viability in order to evaluate the potential of gene therapy in the treatment of MM. MATERIALS AND METHODS: We targeted oxidative phosphorylation by genetically suppressing HIF-1α and miR-210. We have examined mitochondrial activity, cytosolic glycolysis and cell viability. RESULTS: The ratio of NADH/NAD+ in the cytoplasm under normal conditions is stable and can thus serve as a specific cellular metabolic marker. Therefore, the study was aimed at finding the cause of the reduction in NADH levels in increasing hypoxia under ideal in vitro conditions on the SK-MEL-30 malignant melanoma cells. The relationship between HIF-1α and miR-210, their effect on transcriptional level, and the subsequent effect on metabolic process attenuation in cells was investigated. Obtained results indicate that the NADH which is accumulated by cells in hypoxia was significantly decreased upon gene silencing. CONCLUSIONS: Our studies have shown that small regulatory molecules with organelle-specific effect (such as miRs) need to be targeted, and that the resultant effect is comparable to silencing of "general" hypoxic transcription factors.

Relationship between steroid hormones and metabolic profile in women with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is commonly associated with a higher cardiometabolic risk. The relationship between steroid hormones and cardiometabolic profile in PCOS has been evaluated, but no single hormonal predictor of this association has been identified to determine. To determine the relationship between steroid hormones and cardiometabolic risk factors in PCOS women. Study included 64 women diagnosed with PCOS. Fasting blood samples were analyzed for biochemical, metabolic parameters and sex steroid hormones. PCOS women with BMI>/-27 had significantly higher serum free testosterone (FT), free androgen index (FAI), estrone (E1) (p=0.014, p=0.02, p=0.01) than those with normal weight. In all subjects E1 positively correlated with BMI (p=0.0067), serum insulin (p=0.0046), HOMA-IR (p=0.0125) and negatively with HDL-cholesterol (p=0.009). FAI positively correlated with serum cholesterol (p=0.0457), triacylglycerols (TAG) (p=0.0001), HOMA-IR (p=0.037), and glycemia (p=0.0001), negatively with HDL-cholesterol (p=0.029). In multiple linear regression model E1 most significantly predicted HOMA-IR, whereas FT/FAI predicted HDL-cholesterol and BMI. We conclude that PCOS women with marked overweight or obesity have higher FT, FAI and E1 as compared with nonobese PCOS subjects. E1 and FT may predict worse cardiometabolic profile in PCOS.

Evaluation of molecular changes of distal organs after small bowel transplantation.

The ischemia and reperfusion of a jejunal graft during transplantation triggers the stress of endoplasmic reticulum thus inducing the synthesis of pro-inflammatory cytokines. Spreading of these signals stimulate immunological reactions in distal tissues, i.e. lung, liver and spleen. The aim of this study was to detect the molecular changes in liver and spleen induced by transplanted jejunal graft with one or six hours of reperfusion (group Tx1 and Tx6). Analysis of gene expression changes of inflammatory mediators (TNF-alpha, IL-10) and specific chaperones (Gadd153, Grp78) derived from endoplasmic reticulum (ER) was done and compared to control group. The qRT-PCR method was used for amplification of the specific genes. The levels of corresponding proteins were detected by Western blot with immunodetection. Protein TNF-alpha was in liver tissue significantly overexpressed in the experimental group Tx1 by 48 % (p<0.001). In the group Tx6 we found decreased levels of the same protein to the level of controls. However, the protein concentrations of TNF-alpha in spleen showed increased levels in group Tx1 by 31 % (p<0.001) but even higher levels in the group Tx6 by 115 % (p<0.001) in comparing to controls. Our data demonstrated that the spleen is more sensitive to post-transplantation inflammation than liver, with consequent stress of ER potentially inducing apoptosis and failure of basic functions of lymphoid tissue.

Selected physicochemical properties of amniotic fluid according to week of pregnancy.

BACKGROUND: A hundred years ago, scientists believed that amniotic fluid is a yellowish hypotonic mixture of foetal urine and maternal transudate with peculiar odour. Current knowledge shows that it represents a dynamic, complex mixture of inorganic and organic compounds. OBJECTIVES: Despite modern technological procedures, information is still lacking about the composition and properties of amniotic fluid. We focused on dynamics of selected physical and chemical properties of the amniotic fluid with the increasing gestational week. METHODS: The physicochemical characteristics of 89 amniotic fluid samples were determined according to the week of pregnancy. The determination of pH, specific gravity, glucose and nitrites was performed immediately, at room temperature. RESULTS: Our results show a significant negative correlation between week of pregnancy and semi-quantitative determined parameters of specific gravity (p < 0.001), pH (p < 0.01) and glucose (p < 0.001) values. Within the whole group of samples (n = 89), 29 % (n = 26) were nitrites positive (N+) and 71 % (n = 63) nitrites negative (N-). CONCLUSION: In this study were determined basic parameters of amniotic fluid, which could be related to a wide range of pathological states (Tab. 2, Fig. 1, Ref. 27).

[Potential of Using Vitamin D as an Adjuvant Treatment of Malignant Melanoma]. / Potenciál vitamínu D v adjuvantnej liecbe malígneho melanómu koze.

The incidence of malignant melanoma worldwide continues to grow despite the enormous advances in topical and systemic therapy. This increase is recorded regularly even in countries where, as a result of public health campaigns, dermatological examination and subsequent treatment have become more frequent. However, there have been reports of a stable or even decreasing mortality rate that seem to contradict the objective increase in its incidence. The well-known risk factors for malignant melanoma include sunburns and occasional sunbathing, whereas regular sunbathing is associated with a lower incidence. Besides DNA damage, exposure to the sun also results in the synthesis of vitamin D (cholecalciferol) in the skin, which contributes to over 90% of circulating Calcidiol (25 (OH) D) in serum. Current cultural norms (dressing, working indoors, avoiding sun exposure, and dietary choices) affect the serum vitamin D level, resulting in severely low serum levels of vitamin D in some sectors of todays society. Emerging data suggests that mild, unprotected exposure to UV radiation or dietary supplementation with oral vitamin D can reduce cancer mortality. Supplementation with vitamin D or alternatively UV exposure may be regarded as an adjuvant for the treatment of many types of tumors (e.g. tumors of the colon, prostate, and breast). The effect of vitamin D on malignant melanoma may be due to its non-calcemic systemic effects. Additionally, vitamin D may have more pronounced effects locally in the skin because of the unique ability of keratinocytes to synthesize the active form of vitamin D.Key words: malignant melanoma - vitamin D - adjuvant treatment therapy - clinical oncology The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 7. 10. 2016Accepted: 26. 7. 2017.

Analysis of transcriptional activities of angiogenic biomarkers during intrauterine complications leading to preterm birth.

OBJECTIVE: Pre-eclampsia, growth retardation and preterm delivery are the most common reasons leading to increased maternal and perinatal mortality. The increased expression of hypoxia induced factors, such as HIF-1, triggers the overexpression of anti-angiogenic genes. The aim of this study was to determine the transcriptional activity of individual pro- and anti-angiogenic markers (VEGF, HIF-1, sEng, Flt-1, PlGF-1) in maternal blood samples from patients with spontaneous preterm labor, preterm labor in combination with pre-eclampsia and fetal growth restriction in comparison with physiologically terminated pregnancies. PATIENTS AND METHODS: The transcriptional activity of specific genes was detected from the blood of patients using the chromatin immunoprecipitation capture method coupled with quantitative real-time PCR. RESULTS: The maximum differences in mRNA levels of PlGF-1 and VEGF-A were detected in two groups: the group of normal-term birth with complications and the group of preterm labor with complications (both significantly lower than the control, p < 0.001). In contrast, a marked increase of mRNA levels was found in the same groups of patients for the HIF-1, endoglin and Flt-1 genes (p < 0.001). CONCLUSIONS: According to our results, we can conclude that increased oxidative stress, increasing the expression levels of anti-angiogenic genes and reduction of the transcriptional activity of pro-angiogenic genes can provide additional information during diagnostics of pathological complications of labor.

Current knowledge on the active form of Vitamin D synthesized in the skin and its effects on malignant melanoma.

The link between sunlight and skin cancer is a frequently discussed topic. However, ultraviolet radiation also induces the production of Vitamin D in the body. Keratinocytes and their ability to synthesize the active form of Vitamin D, which is consumed at the place of its origin in the skin, have a unique place in this discussion. We observe a remarkable sunshine-related paradox when we monitor the relationship between the dose of solar radiation and one type of skin cancer - malignant melanoma. Recent knowledge of the non-calcemic effects of Vitamin D, which include growth regulation, DNA repair, differentiation, apoptosis, membrane transport, metabolism, cell adhesion and oxidative stress, could help to further clarify this relationship. In this context, adjuvant Vitamin D therapy is currently being considered in patients with malignant melanoma, and this is expected to reduce tumor invasiveness and micrometastases and thus improve patient prognosis and reduce the risk of relapse.

[The Importance of MITF Signaling Pathway in the Regulation of Proliferation and Invasiveness of Malignant Melanoma]. / Význam signálnej dráhy MITF pri regulácii proliferácie a invazivity malígneho melanómu.

BACKGROUND: Malignant melanoma is one of the most aggressive types of cancers. Melanoma is derived from pigment-producing cells, melanocytes, which are characterized by a specific survival mechanism. Microphthalmia-associated transcription factor (MITF-M) plays a role in the metabolism of melanoma and is involved in the regulation of the expression of multiple genes mediating processes such as melanogenesis, proliferation, differentiation, and melanocyte survival. The expression of this transcription factor in melanocytes is activated by several signaling pathways, and reduced expression or function of MITF-M can cause the dysregulation of anti-apoptotic mechanisms. MITF-M is also involved in matrix metalloproteinase 14 (MMP14) activity, which is responsible for shape changes in melanocytes and increases in their motility and invasiveness. Very low levels of expression of MITF-M are found in human melanocytes with an invasive phenotype, indicating that this transcription factor acts as a suppressor of the metastatic process. Cancer cells with low expression of cytosolic/nuclear ß-catenin have a small amount of MITF-M 14 that is insufficient to inhibit MMP transcription. The enzyme catalyzes the degradation of laminin and fibronectin, thereby changing the shape of melanocytes, which leads to their increased mobility and invasiveness. AIMS: This review describes the regulatory pathway of MITF-M activation, its involvement in the proliferation of transformed melanocytes, and its role in increasing the invasiveness of malignant melanoma. A detailed understanding of the MITF-M signaling pathway is highly topical and could help to develop new diagnostic and therapeutic applications for patients with malignant melanoma.Key words: neoplastic cell transformation - melanoma - MITF transcription factorThis work was supported by grant projects VEGA 1/0115/14 and VEGA 1/0873/16.The authors declare they have no potential confl icts of interest concerning drugs, products, or services used in the study.The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 4. 12. 2015Accepted: 14. 6. 2016.

Environmental estrogen bisphenol A and autoimmunity.

Over the past few years, there has been evidence of the increasing prevalence of autoimmune diseases. Autoimmune diseases consist of many complex disorders of unknown etiology resulting in immune responses to self-antigens. The immune system, and its function, is under complex and integrated control and its disruption can be triggered by multiple factors. Autoimmunity development is influenced by multiple factors and is thought to be a result of interactions between genetic and environmental factors. Here, we review the role of a specific environmental factor, bisphenol A (BPA), in the pathogenesis of autoimmune diseases. BPA belongs to the group of environmental estrogens that have been identified as risk factors involved in the development of autoimmune diseases.

Seroprevalence of human Toxocara infections in the Roma and non-Roma populations of Eastern Slovakia: a cross-sectional study.

Socioeconomic conditions and health of the Roma population, the most numerous minority in Europe, are worse than that of the non-Roma population. Information about the occurrence of human toxocarosis and other parasitic diseases in the Roma population is scarce or completely missing. The aim of this study was to map the seroprevalence of toxocarosis in the population living in segregated Roma settlements and to compare the data with the occurrence of antibodies in the non-Roma population of Eastern Slovakia. The seropositivity to Toxocara in 429 examined Roma inhabitants of segregated settlements reached 22·1%, while only 4/394 samples of the non-Roma population were found to be positive (odds ratio 27·7, P < 0·0001). Headache, muscle pain, influenza-like symptoms and diarrhoea occurred significantly more often in seropositive persons than in seronegative individuals. In the Roma population positivity was not influenced by gender, level of education and poverty, but age, lack of sanitary facilities and heating with wood significantly increased the risk of infection. It can be assumed that besides the high prevalence of toxocarosis, other parasitic diseases and communicable diseases will also be more prevalent in the Roma population living in segregated settlements.

Changes in urine autofluorescence in ovarian cancer patients.

Ovarian cancer is the type of cancer with the highest mortality rate among gynaecologic malignancies. Due to lack of screening tools, this disease is mainly diagnosed at a progressed stage, when it is too late to adequate therapy. Despite many attempts, enough sensitive and specific biomarker was not still uncovered. Fluorescence spectroscopy has proven to be a useful diagnostic tool with high efficiency. Fluorescence detection has three major advantages over other light-based investigation methods: high sensitivity, high speed, and reliability. Biological materials consist of a number of intrinsic fluorescent compounds -autofluorophores, which are associated with cardinal metabolic pathways. It is well known, that cancerous tissue metabolism is altered compared to healthy one, what influence also intrinsic fluorophores composition of bodily fluids. Urine is one of the biological fluids that could be obtained most easily and displays a blue - green fluorescence that can change in case of pathological process. Analysis of urine autofluorescence is non invasive and simple technique. Using fluorescent spectroscopy, ovarian cancer patients and healthy control group were discerned with high significance, so we predict that fluorescence analysis of urine could be a potential means of ovarian cancer screening.

[Effect of vitamin d receptor polymorphisms on the development and progression of malignant melanoma]. / Prehlad vplyvu polymorfizmov receptora vitamínu D na vznik a progresiu malígneho melanómu.

BACKGROUND: Malignant melanoma is one of the most aggressive cutaneous tumors in men and women. The risk of developing a malignant melanoma depends on several external factors along with deregulation of mutual interaction of genotype and phenotype. Nowadays, growing attention is focused on the study of the interactions of the active form of vitamin D3 with its receptor and inhibitory effect of vitamin D3 receptor polymorphisms on multiple signaling pathways involved in proliferative and metastatic processes. OBJECTIVES: This review article addresses the relationship between factors involved in the development of malignant melanoma through Hedgehog signaling pathway (HH). It summarizes current knowledge of malignant melanoma in regard to the role of the active form of vitamin D3 binding to vitamin D3 receptor (VDR), as well as it describes the influence of polymorphisms of VDR on the inhibition of HH. Understanding of these mechanisms and critical assessment of available data is beneficial to both primary and secondary prevention of malignant melanoma particularly by means of chemo -preventive substances.

[New and clinically used oncomarkers of bladder cancer]. / Nové a klinicky vyuzívané onkomarkery karcinómu mocového mechúra.

Bladder cancer is the fourth most common cancer in men and the eighth most common cancer in women. Oncomarkers play a crucial role in early detection of bladder cancer, as well as in treatment response monitoring and prognosis. Search for a new marker by molecular analysis is in progress because any diagnostic sensitivity and specificity enhancement is a great benefit for clinical practice.

Progression of apoptic signaling from mesenteric ischemia-reperfusion injury to lungs: correlation in the level of ER chaperones expression.

Multiple organ dysfunction syndrome (MODS) is characterized by the development of probably reversible, progressive dysfunction of vital systems in two or more organs, directly undamaged by surgery or other trauma. The organs which have the most common potential dysfunction are lungs, liver, kidneys, heart and gastrointestinal tract. The small intestine is the source of production of proinflammatory mediators leading and contributing to multiorgan failure. The endoplasmic reticulum (ER), after ischemia and post-ischemic reperfusion, is significantly involved in the activation of enterocyte apoptosis. The purpose of this study was to determine the stage of apoptosis in the lungs, initiated through inflammatory response from the small intestine. We analyzed changes in mRNA levels of pro-apoptotic genes Gadd153 (Chop) and anti-apoptotic genes Grp78 (Bip) in the small intestine wall and lung parenchyma. During experimental procedure the rats underwent 60 min of ischemia, caused by complete occlusion of the mesenteric arteria cranialis, with subsequent reperfusion and evaluation after 1 h, 24 h and 30 days (from R1, R24 to R30, respectively, each group n = 8). The gene expression levels were measured using RT-PCR followed by electrophoresis and visualization under UV. In the lungs we detected significantly lower level of expression Grp78 by 45 ± 6.9%. This suggests that ischemic attack and subsequent reperfusion did not promote ER stress in the lungs through induction of Gadd153 expression in the small intestine. There is still no effective approach to the treatment of affected ischemic intestine tissue, to stop the processes with could eventually lead to MODS. Therefore it is necessary to study changes in the damaged tissue at the molecular level and try to suggest possible therapeutic defined routes to the protection of tissue.

Study of DNA interactions with cyclic chalcone derivatives by spectroscopic techniques.

A series of chalcone derivatives (1-4) were studied. The interaction between these ligands and calf thymus DNA was studied with UV-vis spectrophotometry, fluorescence and circular dichroism spectroscopy. The binding constants K were estimated at 0.5-4.6×10(5) M(-1). All these measurements indicated that the compounds behave as effective DNA-intercalating agents. Electrophoretic separation proved that ligands inhibited topoisomerase I at a concentration of 60 µM.