Milan à Albenga. La coupole perdue du baptistère milanais San Giovanni alle Fonti : un essai de restitution

Cet article propose une hypothèse de restitution de la composition de la coupole du baptistère épiscopal milanais de San Giovanni alle Fonti, disparu depuis presque six siècles. Cette dernière se base sur une analyse des liens qui unissent Milan et ce qui nous est parvenu de l’édifice baptismal d’origine (fragments des murs périphériques, éléments de la décoration) avec le baptistère d’Albenga, encore conservé, qui peut être considéré comme une véritable copie du modèle milanais. Une attention particulière est portée à l’interprétation de la mosaïque qui orne la niche orientale à Albenga, dont l’élément central pouvait, à notre avis, couronner la décoration de la coupole à Milan

Primary Cilia and its Importance in Cell Response to Ionizing Radiation Exposure and Chemotherapy Drugs.

Primary cilia and its importance in cell response to ionizing radiation exposure and chemotherapy drugs. Ionizing radiation, metabolic and genotoxic stress affect the cytoskeletal stability and morphology of cells by causing DNA damage in the form of single or double stranded breaks, the latter being the most critical. When DNA damage occurs the cell cycle becomes arrested and the repair machinery is engaged; however, if this damage is not repaired the cell enters programmed cell death by apoptosis. Primary cilia have been shown to act as physical- chemical sensors and their biological functions include the perception of the extracellular milieu, the regulation of organogenesis and cell polarity, as such, they are dynamically regulated during cell cycle progression. Further, the impairment or loss of primary cilia leads to the development of ciliopathies and other diseases including cardiovascular disorders, arthritis and, ultimately, cancer. Moreover, the presence and temporary formation of primary cilia is essential for the repair process of certain cell types. This work is focused on the evaluation of primary cilia changes caused by ionizing radiation, metabolic stress or cytostatic drugs (taxol and doxorubicin) in vitro. Our results showed a significantly higher number of ciliated C2C12 cells observed...Primární řasinka a její význam v reakci buněk na expozici ionizujícímu záření a cytostatikům. Ionizující záření, metabolický stres vyvolaný hladověním a genotoxický stres působí na buňky v několika úrovních. Ovlivňují cytoskeletální stabilitu a morfologii buňky a způsobují poškození DNA - jednovláknovými anebo dvouvláknovými zlomy. Pro buňku jsou nejkritičtější zlomy dvouvláknové. Jestliže dojde k poškození DNA, dochází k zástavě buněčného cyklu a k reparaci poškození. Pokud toto poškození není opraveno, nastává buněčná smrt apoptózou, mitotická katastrofa nebo senescence. Primární řasinky jsou mikrotubulární organely, které působí jako fyzikálně-chemické senzory a jejich biologické funkce zahrnují vnímání extracelulárního prostředí, regulaci organogeneze a buněčnou polaritu. Primární řasinky jsou dynamicky regulovány během progrese buněčného cyklu. Dnes je již dobře známo, že porucha nebo ztráta primární řasinky vede k rozvoji ciliopathií a dalších civilizačních onemocnění, do kterých můžeme zařadit kardiovaskulární onemocnění, artrózu a v neposlední řadě nádorová onemocnění. V současné době se také uvádí, že dočasná přítomnost a tvorba primární řasinky je nezbytná pro reparaci poškození některých typů buněk. Tato práce je zaměřena na hodnocení změn primární řasinky vyvolaných působením ionizujícího...Ústav lékařské biochemieDepartment of Medical BiochemistryLékařská fakulta v Hradci KrálovéFaculty of Medicine in Hradec Králov

The toxic effect of cytostatics on primary cilia frequency and multiciliation

The primary cilium is considered as a key component of morphological cellular stability. However, cancer cells are notorious for lacking primary cilia in most cases, depending upon the tumour type. Previous reports have shown the effect of starvation and cytostatics on ciliogenesis in normal and cancer cells although with limited success, especially when concerning the latter. In this study we evaluated the presence and frequency of primary cilia in breast fibroblasts and in triple negative breast cancer cells after treatment with cytostatics finding that, in the case of breast fibroblasts, primary cilia were detected at their highest incidence 72 hours after treatment with 120 nM doxorubicin. Further, multiciliated cells were also detected after treatment with 80 nM doxorubicin. On the other hand, treatment with taxol increased the number of ciliated cells only at low concentrations (1.25 and 3.25 nM) and did not induce multiciliation. Interestingly, triple negative breast cancer cells did not present primary cilia after treatment with either doxorubicin or taxol. This is the first study reporting presence of multiple primary cilia in breast fibroblasts induced by Doxorubicin. However, the null effect of these cytostatics on primary cilia incidence in the evaluated TNBC cell lines requires further research

Primary Cilia and its Importance in Cell Response to Ionizing Radiation Exposure and Chemotherapy Drugs.

Primary cilia and its importance in cell response to ionizing radiation exposure and chemotherapy drugs. Ionizing radiation, metabolic and genotoxic stress affect the cytoskeletal stability and morphology of cells by causing DNA damage in the form of single or double stranded breaks, the latter being the most critical. When DNA damage occurs the cell cycle becomes arrested and the repair machinery is engaged; however, if this damage is not repaired the cell enters programmed cell death by apoptosis. Primary cilia have been shown to act as physical- chemical sensors and their biological functions include the perception of the extracellular milieu, the regulation of organogenesis and cell polarity, as such, they are dynamically regulated during cell cycle progression. Further, the impairment or loss of primary cilia leads to the development of ciliopathies and other diseases including cardiovascular disorders, arthritis and, ultimately, cancer. Moreover, the presence and temporary formation of primary cilia is essential for the repair process of certain cell types. This work is focused on the evaluation of primary cilia changes caused by ionizing radiation, metabolic stress or cytostatic drugs (taxol and doxorubicin) in vitro. Our results showed a significantly higher number of ciliated C2C12 cells observed..

For Beauty, Nation and God

The following paper traces the origins and increased interest in the cultural heritage of Georgia on behalf of the local intelligentsia in the 19th century. After describing the circumstances that may have led the new generation of Georgian scholars to a systematic exploration of ancient remains in the Caucasus and medieval ecclesiastical monuments and treasuries, the paper will focus on the main archaeologists of Christian antiquity in Georgia, Dimitri Bakradze and Ekvtime Taqaishvili. Finally, the study outlines the creation of what has been called the Georgian National Treasure. The treasure items, collected from monasteries and settlements all over Georgia and protected from robberies and impetuous art collectors, were sent into exile in 1921, shortly before the short-lived Georgian Democratic Republic’s annexation to the Soviet Union. The thirty-nine boxes, containing manuscripts, icons, precious liturgical vessels and other priceless items, were sent from Batumi to Marseille, via Istanbul, and stored in France until 1945, when Ekvtime Taqaishvili, who had taken care of and protected them over those 24 years, accompanied them back to Tbilisi

Effective Method of Purification of Betulin from Birch Bark: The Importance of Its Purity for Scientific and Medicinal Use.

A new and relatively simple method for purification of betulin from birch bark extract was developed in this study. Its five purification steps are based on the differential solubility of extract components in various solvents and their crystallization and/or precipitation, on their affinity for Ca(OH)2 in ethanol, and on the affinity of some impurities for silica gel in chloroform. In addition, all used solvents can be simply recycled. Betulin of more than 99% purity can be prepared by this method with minimal costs. Various observations including crystallization of betulin, changes in crystals during heating, and attempt of localization of betulin in outer birch bark are also described in this work. The original extract, fraction without betulinic acid and lupeol, amorphous fraction of pure betulin, final crystalline fraction of pure betulin and commercial betulin as a standard were employed to determine the antiproliferative/cytotoxic effect. We used WST-1 tetrazolium-based assays with triple negative breast cancer cell line BT-549. The decrease in cell survival showed clear relationship with the purity of the samples, being most pronounced using our final product of pure crystalline betulin. WST-1 proliferation/cytotoxicity test using triple negative breast cancer cell line BT-549 clearly showed the importance of purity of betulin for biological experiments and, apparently, for its medicinal use

Mitochondrie v biodozimetrii: Hodnocení průtokovou cytometrií in vitro

The JC-1 dye is widely used in apoptosis studies to monitor mitochondrial health. The probe was tested in vitro on two established cell lines and peripheral porcine blood lymphocytes after gamma irradiation (IR) to assess its potential in biodosimetric evaluation. In brief, we stained irradiated and non-irradiated cells with the JC-1 dye to determine the existing changes in mitochondrial membrane potential and monitor cell health through flow cytometry. The stage of injury in these cells was evaluated through an irradiated versus non-irradiated ratio (IVNIR), comparing the relative proportion of polarised cells containing red JC-1 aggregates. We observed a decreasing IVNIR as the radiation dose increased (i.e. 0.5; 1; 2; 4; 6; 8 and 10 Gy), performing the analysis at 4, 8 and 24 h after IR in all the tested cells. The results from the JC1-dye test showed that CD4 T lymphocytes were more sensitive to irradiation than other subpopulations.Barvivo JC-1 se široce používá ve studiích apoptózy ke sledování stavu mitochondrií. Sonda byla testována in vitro na dvou zavedených buněčných liniích a na lymfocytech z periferní prasečí krve po ozáření gama zářením (IR), aby se posoudil její potenciál při biodozimetrickém hodnocení. Stručně řečeno, ozařované a neozářené buňky jsme obarvili barvivem JC-1, abychom určili existující změny mitochondriálního membránového potenciálu a sledovali zdraví buněk pomocí průtokové cytometrie. Stupeň poškození těchto buněk byl vyhodnocen pomocí poměru ozářených a neozářených buněk (IVNIR), přičemž byl porovnán relativní podíl polarizovaných buněk obsahujících červené agregáty JC-1. Pozorovali jsme klesající IVNIR se zvyšující se dávkou záření (tj. 0,5; 1; 2; 4; 6; 8 a 10 Gy), přičemž analýzu jsme provedli po 4, 8 a 24 hodinách po IR u všech testovaných buněk. Výsledky testu s barvivem JC1 ukázaly, že lymfocyty CD4 T byly citlivější na ozáření než ostatní subpopulace

Amount of betulin, betulinic acid, lupeol and other triterpenes in fractions.

<p>Amount of betulin, betulinic acid, lupeol and other triterpenes in fractions.</p

Images of crystals of betulin, fraction B5.

<p>A—microphotograph of crystalline fraction; B—large crystals obtained by slow cooling; C and D—macro- and microphotographs of crystals after free evaporation of ethanol.</p

GC-MS chromatograms of four important fractions.

<p><b>B0</b>—original extract, <b>A1</b>—by-product enriched with betulinic acid, <b>L2</b>—by-product enriched with lupeol, <b>B5</b>—pure betulin; BA—betulinic acid; relative detector response (Y-axis) against retention time in minutes (X-axis).</p