Search results for "Rites"
showing 10 items of 427 documents
Primmorphs generated from dissociated cells of the sponge Suberites domuncula: a model system for studies of cell proliferation and cell death
1999
Sponges (Porifera) represent the lowest metazoan phylum; they have been shown to be provided with the characteristic metazoan structural and functional molecules. One autapomorphic character of sponges is the presence of high levels of telomerase activity in all cells (or almost all cells, including somatic cells). In spite of this fact previous attempts to cultivate sponge cells remained unsuccessful. It was found that dissociated sponge cells do not replicate DNA and lose their telomerase activity. In addition, no nutrients or metabolites have been detected that would stimulate sponge cells to divide. In the present study we report the culture conditions required for the formation of mult…
Sponge homologue to human and yeast gene encoding the longevity assurance polypeptide: differential expression in telomerase-positive and telomerase-…
2000
Porifera show a characteristic Bauplan in spite of the fact that (almost) all cells are telomerase-positive and presumably provided with an unlimited potency for cell proliferation. Studies revealed that telomerase-positive cells can be triggered to telomerase-negative cells by dissociating them into single cells. Single cells from the demosponge Suberites domuncula, in contrast to cells present in primmorphs (a special form of cell aggregates), lack the property to proliferate and they undergo apoptosis. One gene, SDLAGL, was identified in primmorphs that showed high sequence similarity to the longevity assurance genes from other Metazoa. In single cells no transcripts of SDLAGL could be i…
Telomere Shortening in Neural Stem Cells Disrupts Neuronal Differentiation and Neuritogenesis
2009
Proliferation in the subependymal zone (SEZ) and neurogenesis in the olfactory bulb decline in the forebrain of telomerase-deficient mice. The present work reveals additional effects of telomere shortening on neuronal differentiation, as adult multipotent progenitors with critically short telomeres yield reduced numbers of neurons that, furthermore, exhibit underdeveloped neuritic arbors. Genetic data indicate that the tumor suppressor protein p53 not only mediates the adverse effects of telomere attrition on proliferation and self-renewal but it is also involved in preventing normal neuronal differentiation of adult progenitors with dysfunctional telomeres. Interestingly, progenitor cells …
La kalimera di Lazzaro: Varianti testuali siculo-arbëreshe
2018
This kalimera forms part of an ancient pagan rite of agricultural fertility, which due to syncretism is conserved in the paraliturgical practices still existing in the Arbëresh communities in southern Italy.Belonging to the cycle of commemoration of the dead, Lazarus’ Saturday is the second of the four Saturdays (the first is that of the carnival – in Alb. E shtuna e shpirtravet), during which participants sing the ballad of Constantine and Doruntina; the second Saturday, as mentioned, is that of the Resurrection of Lazarus, featuring liturgical hymns known as the hymns of the Holy Week; the third is the Saturday on the Easter’s Eve when the bells were untied; the fourth Saturday is that of…
Determination of nitrite by inhibition of the chemiluminescence of acriflavine in a flow-injection assembly
2001
The indirect determination of nitrite was performed with a flow-injection assembly on the basis of the inhibition of the analytical output obtained in a luminometer by oxidation of acriflavine. The acriflavine solution merged with the nitrite and the resulting mixture was injected into a pure water stream. This solution merged with the oxidant solution (potassium permanganate in sulfuric acid medium) and the resulting chemiluminiscence was affected (inhibited) by the presence of nitrite after reaction with the aminoacridine. The method was applicable over the range 10–800 μg l−1 of nitrite with a correlation coefficient of 0.9960. The relative standard deviation was 1.4% and the throughput …
Contribution of sponge genes to unravel the genome of the hypothetical ancestor of Metazoa (Urmetazoa)
2001
Recently the term Urmetazoa, as the hypothetical metazoan ancestor, was introduced to highlight the finding that all metazoan phyla including the Porifera (sponges) are derived from one common ancestor. Sponges as the evolutionarily oldest, still extant phylum, are provided with a complex network of structural and functional molecules. Analyses of sponge genomes from Demospongiae (Suberites domuncula and Geodia cydonium), Calcarea (Sycon raphanus) and Hexactinellida (Aphrocallistes vastus) have contributed also to the reconstruction of the evolutionary position of Metazoa with respect to Fungi. Furthermore, these analyses have provided evidence that the characteristic evolutionary novelties…
Anthemis wiedemanniana essential oil prevents LPS-induced production of NO in RAW 264.7 macrophages and exerts antiproliferative and antibacterial ac…
2012
Anthemis wiedemanniana is known in folk medicine for the treatment of microbial infections, cancer and also urinary and pulmonary problems. In this study, the chemical composition of the essential oil from A. wiedemanniana was evaluated and its antibacterial activity was tested against 10 bacterial strains. The oil was also tested for its potentiality to inhibit nitric oxide production in RAW 264.7 macrophages and for its cytotoxicity against four human cancer cell lines. A. wiedemanniana oil, rich of oxygenated monoterpenes (25.4%), showed a good antibacterial activity against Gram-positive bacteria and a good activity against the two Gram-negative bacteria, Escherichia coli and Proteus vu…
Betanin inhibits the myeloperoxidase/nitrite-induced oxidation of human low-density lipoproteins
2007
Production of nitrogen dioxide by the activity of myeloperoxidase (MPO) in the presence of nitrite is now considered a key step in the pathophysiology of low-density lipoprotein (LDL) oxidation. This study shows that betanin, a phytochemical of the betalain class, inhibits the production of lipid hydroperoxides in human LDL submitted to a MPO/nitrite-induced oxidation. Kinetic measurements including time-course of particle oxidation and betanin consumption, either in the presence or in the absence of nitrite, suggest that the antioxidant effect is possibly the result of various actions. Betanin scavenges the initiator radical nitrogen dioxide and can also act as a lipoperoxyl radical-scaven…
Atmospheric CO2 Concentrations in Caves Protected as Nature Reserves and Related Gas Hazard
2022
Atmospheric CO2 concentrations can reach high levels inside natural caves, representing a hazardous condition for both humans frequenting the underground environment and its safeguard due to the corrosion of speleothems induced by the acidification of atmospheric moisture. These issues are particularly critical for the eco-sustainable management of caves protected as nature reserves and undergoing touristic exploitation. In this paper we present the results of the C6 project, which was activated in 1999 for the monitoring of air quality inside three caves protected as nature reserves in Sicily (Italy). Near-real-time and spot measurements of air temperature and CO2 concentration have been c…
Seismic stratigraphy of upper Quaternary shallow-water contourite drifts in the Gulf of Taranto (Ionian Sea, southern Italy)
2018
Abstract The occurrence of articulated seafloor morphology over continental shelf-upper slope environments, may result in a significant change in the patterns and intensity of basin-scale thermohaline circulation during eustatic sea-level fluctuations. These changes may cause, in turn, erosion, deposition and/or transport of sediments at the seafloor, to form shallow-water contourite drifts. Here we investigate this process in the NW sector of the Gulf of Taranto (Ionian Sea) during and following the Last Glacial Maximum (LGM), by integrating multibeam bathymetric data, ultra-high resolution seismic-reflection data and gravity core data. Sea level fall caused subaerial exposure of the summi…