An Ancient Relation between Units of Length and Volume Based on a Sphere

The modern metric system defines units of volume based on the cube. We propose that the ancient Egyptian system of measuring capacity employed a similar concept, but used the sphere instead. When considered in ancient Egyptian units, the volume of a sphere, whose circumference is one royal cubit, equals half a hekat. Using the measurements of large sets of ancient containers as a database, the article demonstrates that this formula was characteristic of Egyptian and Egyptian-related pottery vessels but not of the ceramics of Mesopotamia, which had a different system of measuring length and volume units

ISOLATION OF ANTIPROLIFERATIVE COMPOUNDS FROM CENTAUREA JACEA L.

Antiproliferative screening of 53 Asteraceae species against human tumour cell lines demonstrated a high cell proliferation inhibitory activity of the Centaurea species native to Middle and Eastern Europe. The highest activity was recorded for C. jacea, whose chloroform extract, prepared from different plant parts, significantly inhibited the growth of HeLa (57-86 %), MCF7 (44-64 %) and A431 (43-69 %) cells in 10 µg/ml concentrations. This species is a perennial herb occurring widespread in Europe. Its anti-tumour constituents have not been investigated earlier. Previous studies revealed the presence of flavones, flavonols, sesquiterpenes and cinnamic alcohol glucosides. The aim of the present work was the isolation and identification of the antiproliferative compounds from the aerial parts of C. jacea using bioactivity guided fractionations. The chloroform extract was chromatographed by CC on silica gel and polyamide, and further separated by CPC, PLC and RP-HPLC, to yield 10 pure compounds. Structure determinations were carried out by means of UV, MS and NMR spectroscopy and the comparison of the spectral data with literature values. The results allowed the identification of the flavonoid apigenin, axillarin, centaureidin, cirsiliol and isokaempferide, the sesquiterpene 4’-acetylcnicin, one new dibenzylbutyrolactone-type lignane, and three aliphatic glucose diesters, including the new natural product 1-beta-isobutanoyl-2-angeloylglucose. All compounds were isolated for the first time from this species. The isolated compounds were evaluated for their tumour cell inhibitory activity on HeLa, MCF7 and A431 cells and it was found that besides the extremely active centaureidin (IC50 0.0819–0.3540 microM), cirsiliol, isokaempferide, apigenin and 4’-acetylcnicin also exerted remarkable effects. Acknowledgements: This work was supported by grant OTKA K72771

mammalian DNA topoisomerase I and cytostaticity assays

Benzimidazoles are important compounds because of their antibacterial, antifungal, antimicrobial, antiprotozoal and antihelmintic activities. Some benzimidazole derivatives also interfere with the reactions of DNA topoisomerases, enzymes functioning at almost all stages of the cell cycle. In this study, nine 1H-benzimidazole derivatives with substituents at positions 2 and 5 were synthesized and the structure of the compounds was elucidated by instrumental methods. The characterized compounds were screened to identify if they interfered with mammalian type I DNA topoisomerase activity via in vitro supercoil relaxation assays. Selected compounds were subjected to cytostatic assays using HeLa (cervix adenocarcinoma), MCF7 (breast adenocarcinoma) and A431 (skin epidermoid carcinoma) cells. Our results showed that 5-chloro-2-(2-hydroxyphenyl)-1H-benzimidazole exerted the most profound topoisomerase I inhibition and cytotoxicity. (C) 2008 Published by Elsevier Masson SAS

type I and type II DNA topoisomerase reactions

Majority of anti-cancer drugs were shown to exert their activities by interfering with DNA topoisomerase reactions. Since the identification of Camptothecin as the topoisomerase I targeting compound, these enzymes are widely utilized in biological assays to assess the pharmaceutical significance of the synthetic and natural agents. Because a considerable number of compounds were shown to have cytostatic activities via blocking topoisomerase reactions, we aimed to identify if the previously-reported physiological activities of acetonapthones involves the interference with topoisomerase reactions. We covered topoisomerase activity and cytostatic activity evaluation of piperidinopropionaphthone hydrochloride type Mannich base (MB) to compare its bioactivities to the starting propionaphtone in order to assess the contribution of aminomethyl moiety of the compound on its bioactivity. MB was synthesized and characterized in our laboratory. Supercoiled plasmid relaxation and decatenation assays were carried out to evaluate their biological activities in mammalian DNA topoisomerases. We also assayed the cytostatic activities using HeLa, MCF7 and A431 cell lines. Our data showed a considerable inhibition of MB on type I and type II DNA topoisomerases without a correlation to cytostatic assays. MB exerted a modest activity against the proliferation of MCF7 cells with an IC50 value of 27.62 mu M. The presence of MB inhibited topo II decatenation activity as well. Results offer no direct explanation for the contradictory effects on the DNA topoisomerases and the proliferation of cancer cells in vitro. Our results are discussed in relation to potential significance of aminomethyl group of Mannich base in the course of drug-development studies

type I and type II DNA topoisomerase reactions

Majority of anti-cancer drugs were shown to exert their activities by interfering with DNA topoisomerase reactions. Since the identification of Camptothecin as the topoisomerase I targeting compound, these enzymes are widely utilized in biological assays to assess the pharmaceutical significance of the synthetic and natural agents. Because a considerable number of compounds were shown to have cytostatic activities via blocking topoisomerase reactions, we aimed to identify if the previously-reported physiological activities of acetonapthones involves the interference with topoisomerase reactions. We covered topoisomerase activity and cytostatic activity evaluation of piperidinopropionaphthone hydrochloride type Mannich base (MB) to compare its bioactivities to the starting propionaphtone in order to assess the contribution of aminomethyl moiety of the compound on its bioactivity. MB was synthesized and characterized in our laboratory. Supercoiled plasmid relaxation and decatenation assays were carried out to evaluate their biological activities in mammalian DNA topoisomerases. We also assayed the cytostatic activities using HeLa, MCF7 and A431 cell lines. Our data showed a considerable inhibition of MB on type I and type II DNA topoisomerases without a correlation to cytostatic assays. MB exerted a modest activity against the proliferation of MCF7 cells with an IC50 value of 27.62 mu M. The presence of MB inhibited topo II decatenation activity as well. Results offer no direct explanation for the contradictory effects on the DNA topoisomerases and the proliferation of cancer cells in vitro. Our results are discussed in relation to potential significance of aminomethyl group of Mannich base in the course of drug-development studies

The interference of piperidinopropionaphthone hydrochloride in mammalian type I and type II DNA topoisomerase reactions

Majority of anti-cancer drugs were shown to exert their activities by interfering with DNA topoisomerase reactions. Since the identification of Camptothecin as the topoisomerase I targeting compound, these enzymes are widely utilized in biological assays to assess the pharmaceutical significance of the synthetic and natural agents. Because a considerable number of compounds were shown to have cytostatic activities via blocking topoisomerase reactions, we aimed to identify if the previously-reported physiological activities of acetonapthones involves the interference with topoisomerase reactions. We covered topoisomerase activity and cytostatic activity evaluation of piperidinopropionaphthone hydrochloride type Mannich base (MB) to compare its bioactivities to the starting propionaphtone in order to assess the contribution of aminomethyl moiety of the compound on its bioactivity. MB was synthesized and characterized in our laboratory. Supercoiled plasmid relaxation and decatenation assays were carried out to evaluate their biological activities in mammalian DNA topoisomerases. We also assayed the cytostatic activities using HeLa, MCF7 and A431 cell lines. Our data showed a considerable inhibition of MB on type I and type II DNA topoisomerases without a correlation to cytostatic assays. MB exerted a modest activity against the proliferation of MCF7 cells with an IC50 value of 27.62 μM. The presence of MB inhibited topo II decatenation activity as well. Results offer no direct explanation for the contradictory effects on the DNA topoisomerases and the proliferation of cancer cells in vitro. Our results are discussed in relation to potential significance of aminomethyl group of Mannich base in the course of drug-development studies. © 2015, Marmara University. All rights reserved

type I and type II DNA topoisomerase reactions

Majority of anti-cancer drugs were shown to exert their activities by interfering with DNA topoisomerase reactions. Since the identification of Camptothecin as the topoisomerase I targeting compound, these enzymes are widely utilized in biological assays to assess the pharmaceutical significance of the synthetic and natural agents. Because a considerable number of compounds were shown to have cytostatic activities via blocking topoisomerase reactions, we aimed to identify if the previously-reported physiological activities of acetonapthones involves the interference with topoisomerase reactions. We covered topoisomerase activity and cytostatic activity evaluation of piperidinopropionaphthone hydrochloride type Mannich base (MB) to compare its bioactivities to the starting propionaphtone in order to assess the contribution of aminomethyl moiety of the compound on its bioactivity. MB was synthesized and characterized in our laboratory. Supercoiled plasmid relaxation and decatenation assays were carried out to evaluate their biological activities in mammalian DNA topoisomerases. We also assayed the cytostatic activities using HeLa, MCF7 and A431 cell lines. Our data showed a considerable inhibition of MB on type I and type II DNA topoisomerases without a correlation to cytostatic assays. MB exerted a modest activity against the proliferation of MCF7 cells with an IC50 value of 27.62 mu M. The presence of MB inhibited topo II decatenation activity as well. Results offer no direct explanation for the contradictory effects on the DNA topoisomerases and the proliferation of cancer cells in vitro. Our results are discussed in relation to potential significance of aminomethyl group of Mannich base in the course of drug-development studies

The interference of piperidinopropionaphthone hydrochloride in mammalian type I and type II DNA topoisomerase reactions [Piperidinopropiyonafton hidroklorür bileşiğinin tip I ve tip II memeli DNA topoizomeraz enzimleri üzerindeki etkisi]

Majority of anti-cancer drugs were shown to exert their activities by interfering with DNA topoisomerase reactions. Since the identification of Camptothecin as the topoisomerase I targeting compound, these enzymes are widely utilized in biological assays to assess the pharmaceutical significance of the synthetic and natural agents. Because a considerable number of compounds were shown to have cytostatic activities via blocking topoisomerase reactions, we aimed to identify if the previously-reported physiological activities of acetonapthones involves the interference with topoisomerase reactions. We covered topoisomerase activity and cytostatic activity evaluation of piperidinopropionaphthone hydrochloride type Mannich base (MB) to compare its bioactivities to the starting propionaphtone in order to assess the contribution of aminomethyl moiety of the compound on its bioactivity. MB was synthesized and characterized in our laboratory. Supercoiled plasmid relaxation and decatenation assays were carried out to evaluate their biological activities in mammalian DNA topoisomerases. We also assayed the cytostatic activities using HeLa, MCF7 and A431 cell lines. Our data showed a considerable inhibition of MB on type I and type II DNA topoisomerases without a correlation to cytostatic assays. MB exerted a modest activity against the proliferation of MCF7 cells with an IC50 value of 27.62 µM. The presence of MB inhibited topo II decatenation activity as well. Results offer no direct explanation for the contradictory effects on the DNA topoisomerases and the proliferation of cancer cells in vitro. Our results are discussed in relation to potential significance of aminomethyl group of Mannich base in the course of drug-development studies. © 2015, Marmara University. All rights reserved