Comparison of selected gene expression profiles in sensitive and resistant cancer cells treated with doxorubicin and Selol.

Aim Of The Study: Cellular resistance is strongly correlated with the risk of failure in doxorubicin (DOX) treatment, and the knowledge of the mechanisms of resistance and its possible modulation is still very limited.

Material And Methods: In this study, we assessed the effect of 5% Selol and DOX on the expression of genes that affect cell proliferation in the resistant KB-V1 and sensitive HeLa cell lines, using RT2 ProfilerTM PCR Array matrix "Human Cancer Drug Resistance and Metabolism" (SABiosciences).

Results: We showed that HeLa and KB-V1 cell lines, characterised by varying susceptibility to DOX, have different genetic profiles as regards the studied genes.

The influence of Selol on the expression of oxidative stress genes in normal and malignant prostate cells.

Selol is a mixture of selenitriglycerides, obtained by the chemical modification of sunflower oil, which contain selenium at the +4 oxidation state. The aim of the present study was to describe the changes in the expression of genes related to oxidative stress caused by Selol in prostate cells: both normal (PNT1A) and malignant (LNCaP). The changes in gene expression in PNT1A and LNCaP cell lines under the influence of Selol were measured using a 96-well RT(2) Profiler ™PCR Array: Human Oxidative Stress and Antioxidant Defense, which arrayed 84 genes functionally involved in the cellular oxidative stress response.

New potential renin inhibitors with dipeptide replacements in the molecule.

A series of eight non-peptidic potential renin inhibitors have been designed and synthesized. All of them contain dipeptide replacement: (3S,4S)-4-amino-5-cyclohexyl-3-hydroxypentanoic acid (ACHPA) in their molecules. Four among them comprise two additional analogs of dipeptide: (3S,4S)-4-amino-3-hydroxy-5-phenylpentanoic acid (AHPPA) and (3S,4S)-4-amino-3-hydroxy-6-methylheptanoic acid (statine, Sta).

New renin inhibitors containing pseudodipeptidic units in P3-P2 and P1-P1' positions.

A series of four non-peptidic renin inhibitors have been designed and synthesized. All of them contain in their molecule (3S,4S)-4-amino-5-cyclohexyl-3-hydroxypentanoic acid (ACHPA), a hydrophobic portion at the C-terminus and a second dipeptide-like transition state analog or unnatural dipeptidic fragment at the N-terminus. Inhibitory activity of the compounds was measured in vitro by high performance liquid chromatography (HPLC).

The separation of EPO from other proteins in medical products formulated with different stabilizers.

The RP-HPLC method, useful for the separation of a protein of the erythropoietin formulations with different stabilizers, was elaborated. Using this method, rhEPO, HSA and other proteins, can be determined, depending on the sample composition. The method is sensitive and rapid.

Determination of in vitro activity renin inhibitors by HPLC method.

A high-performance liquid chromatographic assay has been developed to the separation of angiotensin I, tetradecapeptide and the tetrapeptide Leu-Val-Tyr-Ser. This purpose is achieved in a single step, using HPLC technique in the reversed phase system. The method is based on enzymatic hydrolysis of a substrate renin (TDP) with formation of angiotensin I (DP).

Application of the HPLC method for benzalkonium chloride determination in aerosol preparations.

Benzalkonium chloride (BAC) is a bacteriostatic agent used in the pharmaceutical industry as a preservative. BAC is a mixture of alkylbenzyldimethylammonium chlorides, the three most important of which being those with alkyl substituents C12, C14, C16 at the quaternary ammonium salt. The purpose of this study was to develop a method for determining benzalkonium chloride identity and content in aerosol preparations in which protein or steroid hormones are the active components.

Application of high-performance size exclusion chromatography to the determination of erythropoietin in pharmaceutical preparations.

High performance size exclusion chromatography with fluorimetric detection for the determination of erythropoietin in pharmaceutical preparations has been developed. The applied chromatographic system has been enabled a quick estimation of the identity and contents of the studied compound. The method was validated and showed good validation data in terms of linearity, precision and repeatability.

Determination of the content of desmopressin in pharmaceutical preparations by HPLC and validation of the method.

The aim of this study was to apply high performance liquid chromatography to the determination of content of desmopressin in pharmaceutical preparations and validation of the method. The satisfactory results have been obtained using a column Luna C 8.5 microm, 100 x 4.