[Benefits and the accuracy of the intra-operative frozen section at suspected ovarian tumours]. / Prínos a validita peroperacní frozen section u suspektních ovariálních tumoru.

OBJECTIVE: To assess benefits and the accuracy of the intra-operative frozen section for the operative strategy at suspected ovarian tumours. TYPE OF STUDY: Retrospective study. SETTING: Department of Obstetrics and Gynaecology, Faculty of Medicine and Dentistry, Palacky University in Olomouc. MATERIALS AND METHODS: Intraoperative frozen section and final histopathology were compared in 53 patients who underwent operative treatment for suspected ovarian neoplazma. The accuracy of the frozen section findings was evaluated according to the histopatological type of tumours and categories - benign, malignant and borderline tumours. CONCLUSION: In accordance with literature reports a good reliability of the frozen section as for the sensitivity, specificity, positive and negative predictive values were proved. The majority of errors occured in diagnosing mucinous and borderline tumours.

[HELLP syndrome complicated by liver rupture - case report]. / HELLP syndrom komplikovaný rupturou jater - kazuistika.

OBJECTIVE: A case of HELLP syndrome complicated by liver rupture in the 36th week of pregnancy. DESIGNS: A case report. SETTING: Department of Obstetrics and Gynaecology, FN Olomouc. CASE REPORT: The authors report a case of 31 years old female patient who came to the hospital at 36th week of pregnancy with epigastric pain lasting about 14 days. The problems became worse in the last 10 hours. At admission, the patient was pale with repeatedly unmeasurable blood pressure, and she had lower limbs oedema. There was performed the caesarian section, during the operation the liver rupture was found. Both, patient and her baby, was saved thanks to the concerted interdisciplinary team work. CONCLUSION: One of the most serious complications of HELLP syndrome is liver rupture. It occurs in 3.8% of HELLP syndrome cases. The solution of this complication is to perform an acute operation. The operation is based on liver suture with application of deep mattress suture, applying hemostatic materials, liver compression by Mikulicz´s tamponade or ligation of liver artery. There is also possibility to use omentoplasty. If there is necessity of liver resection for necrotic focus, the argon coagulative laser is used preferably.

Improved synthesis, antibacterial activity and potential carcinogenicity of 5-amino-1 ,2,4-thiadiazol-3(2H)-one.

This paper reports on the preparation of 5-amino-1,2,4-thiadiazol-3(2H)-one, a sulfur-containing analogue of cytosine with the -CH=CH- group between the positions 5 and 6 of the pyrimidine ring replaced by the divalent sulfur (-S-). Improved procedures for the preparation of thiobiuret, some of its methyl derivatives and 5-amino-1,2,4-thiadiazol-3(2H)-one are documented. Thiobiuret and its N-methyl derivatives were obtained by addition of hydrogen sulfide to the respective 1-cyanoureas. Subsequent oxidation of thiobiuret with hydrogen peroxide in alkaline medium produced 5-amino-1,2,4-thiadiazol-3(2H)-one. This substance was traced back converted to the starting thiobiuret by reaction with cysteine hydrochloride. Alkaline degradation of thiadiazol led to the formation of 1-cyanourea isolated as its silver salt. An investigation of the thiadiazol biological activities has shown that it inhibits the growth of E. coil by 10% at 8.5 microM concentrations, but exhibited no cytostatic activity in L1210, HeLa S3 and HL-60 cell lines. Potential carcinogenicity of the prepared compounds was determined by a DC polarographic method. While the values of the parameter of carcinogenicity for all intermediates indicate only marginal carcinogenic potential, the value of the parameter of carcinogenicity for the thiadiazole indicates possible carcinogenicity of this compound.

Pentacyclic triterpenoic acids: new chemoprotective compounds. Minireview.

Ursolic acid and oleanolic acid are pentacyclic triterpenoic acids having a similar chemical structure and are the major components of some oriental and traditional medicine herbs wildly distributed all over the world. There is a growing interest in the elucidation of the biological roles of both these triterpenoid compounds. This review summarizes the biological activities of presented triterpenoid acids (anti-inflammatory, hepatoprotective, gastroprotective, anti-ulcer, anti-HIV, cardiovascular, hypolipidemic, antiatherosclerotic and immunoregulatory effects). Our interest has been focussed especially on their anti-tumor and chemopreventive activity. Both compounds have been shown to act at various stages of tumor development, including inhibition of tumorigenesis, inhibition of tumor promotion, and induction of tumor cell differentiation. They effectively inhibit angiogenesis, invasion of tumor cells and metastasis. However, the mechanisms by which they act are poorly understood. Ursolic acid and oleanolic acid are relatively non-toxic and could be use as chemopreventive/chemoprotective agents in clinical praxis.

Determination of free radical scavenging activity of quercetin, rutin, luteolin and apigenin in H2O2-treated human ML cells K562.

We investigated protective effects of four flavonoids against H2O2- induced DNA damage in human myelogenous leukemia cells (K562) using the comet assay. The structural difference of studied flavonoids -- quercetin, rutin, luteolin and apigenin -- are characterized by the number of hydroxyl groups on the B ring. The presence of an o-dihydroxy structure on the B-ring confers a higher degree of stability to the flavonoid phenoxyl radicals by participating in electron delocalization and is, therefore, an important determinant for antioxidative potential. The results correlate with earlier published data obtained in murine leukemia cell line L1210. Hydrogen peroxide induced in human K562 cells a concentration-dependent increase of single cell DNA strand breaks. The strongest inhibition against H2O2-induced DNA damage (44%, 42%) was found in a range of luteolin and quercetin concentrations of 20-100 micromol/l. Protective effect of rutin (100 and 1000 micromol/l) was only marginal (8-10%). Apigenin had no protective effect on DNA single strand breaks induced by H2O2. Luteolin and quercetin are therefore effective in the protection of human single cell DNA from oxidative attack.

Taraxasterol and beta-sitosterol: new naturally compounds with chemoprotective/chemopreventive effects.

Substantial attention has been given to primary cancer prevention in daily life. Dietary factors are through to contribute to as much as one-third of the factors influencing the development of cancer. Ones of the components of a plant-based diet are beta-sitosterol and taraxasterol, compounds attracting our specific attention. This review summarizes the biological activities of presented phytosterols (anti-inflammatory, cholesterol-lowering, anti-microbial, anti-bacterial, anti-fungal effects). Our interest has been focussed especially on their anti-tumor and chemopreventive activity. They have been shown experimentally to inhibit colon and breast cancer development. They act at various stages of tumor development, including inhibition of tumorigenesis, inhibition of tumor promotion, and induction of cell differentiation. They effectively inhibit invasion of tumor cells and metastasis. With regard to toxicity, no obvious side effects of phytosterols have been observed in studies to date, with the exception of individuals with phytosterolemia. The exact mechanism by which dietary phytosterols act is not fully understood. However, some mechanisms have been offered. Therefore, they have a bright future in clinical application. Further investigation to explore their potential in tumor treatment may prove to be worthwhile.

The free radical scavenging activity of four flavonoids determined by the comet assay.

Flavonoids are reported to exhibit a wide variety of biological effects, including antioxidant and free radical scavenging activities. The aim of our study was to determine the cytotoxicity of flavonoids quercetin, rutin, apigenin and luteolin and their ability to protect DNA molecules against H2O2-induced damage. Cytotoxicity of studied flavonoids was tested in murine leukemia L1210 cells by the trypan blue exclusion technique. DNA strand breaks were determined using the alkaline single-cell gel electrophoresis (comet assay). Quercetin was found to possess the highest protective effect among the flavonoids studied (45%). The protective activity determined was lower for luteolin (40%). Protective effect of apigenin (600 microM/L) was only marginal (2%). However, at the higher concentration of apigenin (1200 microM/L), this flavonoid induced DNA single strand breaks. This indicates the ability of apigenin to serve as a pro-oxidant. Rutin had no protective effect on DNA single strand breaks induced by H2O2.

Flavonoids as chemoprotective agents in civilization diseases.

Flavonoids, a class of polyphenolic compounds widely distributed in the plant kingdom, are capable of protecting against several chronic and degenerative diseases, among them cancer, cardiovascular diseases, stroke, cataracts and brain and immune dysfunctional states. These substances are common dietary components. They exhibit many biological properties through various mechanism of activity. Early studies of flavonoids investigated their significant antioxidant, antitumor, anti-inflammatory, antiallergenic and hepatoprotective effect. Additionally, their ability to modulate the activity of various enzymes affects normal as well as malignant systems. This review summarizes data on the beneficial effects of flavonoids in humans.

Phosphatidylglycerolphosphate synthase encoded by the PEL1/PGS1 gene in Saccharomyces cerevisiae is localized in mitochondria and its expression is regulated by phospholipid precursors.

The PEL1/PGS1 gene of the yeast Saccharomyces cerevisiae is essential for the viability of rho-/rho degrees mutants and the normal cardiolipin content of cells. The PEL1-GFP fusion gene has been found to complement the pel1/pgs1 mutation and its fluorescent protein was localized to mitochondria similarly to the beta-galactosidase activity of a protein encoded by the PEL1-lacZ fusion gene. The expression of the PEL1-lacZ reporter gene was repressed in cells grown in the presence of inositol and choline, reduced in the ino2 and ino4 strains, but constitutive in the opi1 null-mutant strain. The results demonstrate that Pel1p, playing a vital role in cells impaired in the mitochondrial DNA, is localized in the mitochondria and expressed in response to inositol and choline.

Isolation and molecular analysis of the gene for cytochrome c1 from Kluyveromyces lactis.

By ethyl methanesulphonate mutagenesis of the yeast Kluyveromyces lactis we have isolated five nuclear mutants that were unable to grow on non-fermentable carbon sources. The mutations were found to belong to three complementation groups. After functional complementation of the mutation in one of these mutants we have cloned the structural gene for cytochrome c1, named KlCYT1. This gene has been assigned to chromosome VI and its nucleotide sequence exhibited 74.3% identity to the homologous gene of S. cerevisiae.