Sulphated Polysaccharides and the Differentiation of the Cellular Slime Mould Dictyostelium Discoideum

SUMMARYCell surface and endocellular polysaccharides of growing and differentiated Dictyostelium discoideum have been isolated and characterized with electrophoretic and chromatographyc procedures.The mould exhibit a very eterogeneous family of sulphated polysaccharides which are externalized during the differentiation.The possible role of cell surface polysaccharides in the differentiation process is discussed

La conoscenza del materiale e dell’opera per una gestione e un recupero sostenibile dei manufatti lapidei: metodo e applicazione sull’involucro di marmo della Casa delle Armi di Luigi Moretti

La sostenibilità in architettura è una materia complessa che, nel caso dei materiali naturali, diventa particolarmente insidiosa a causa dell’ambivalente caratteristica di questi ultimi: naturali per genesi, estratti a danno dell’ambiente e lavorati artificialmente per poi tornare a integrarsi nell’ambiente stesso a fine vita. Ulteriore complicazione si riscontra quando, dal progetto del nuovo, si passa allo studio del patrimonio esistente: in tal caso, pur essendo compiuto e ormai definito quasi tutto il ciclo di vita del manufatto, restano ulteriori spazi progettuali e tecnici che richiedono, tuttavia, un approccio differente al concetto di sostenibilità. L’articolo descrive una proposta metodologica che si basa sulla conoscenza del manufatto in tutti i suoi aspetti – materici, ambientali e costruttivi – e che trova nel materiale lapideo significative specificità dovute alle caratteristiche di tale materiale. La Casa delle Armi di Luigi Moretti, che presenta un involucro in marmo di Carrara di grande importanza nell’ambito dell’architettura del novecento, costituisce un caso di studio ideale ed è attualmente oggetto di una specifica attività di ricerca del gruppo degli Autori, che svolgono tale attività in collaborazione tra il DICEA di Roma Sapienza e la società Sport e Salute, ex CONI Servizi, che ha in gestione l’edificio. Gli studi in corso comprendono ricerche di archivio ma anche indagini nel comparto produttivo di provenienza del materiale e rilievi sperimentali eseguiti in situ. Alcuni dei metodi utilizzati, quali lo studio termografico e microscopico, non risultano allo stato attuale avere riscontri confrontabili nella letteratura scientifica relativa a questo tipo di opere e, coordinati con le indagini storiche, costituiscono una proposta metodologica originale che si ritiene di proporre anche per altri manufatti dello stesso periodo, spesso dotati di caratteristiche e problematiche analoghe a quelle dell’opera in esame

A model of anti-angiogenesis: differential transcriptosome profiling of microvascular endothelial cells from diffuse systemic sclerosis patients

The objective of this work was to identify genes involved in impaired angiogenesis by comparing the transcriptosomes of microvascular endothelial cells from normal subjects and patients affected by systemic sclerosis (SSc), as a unique human model disease characterized by insufficient angiogenesis. Total RNAs, prepared from skin endothelial cells of clinically healthy subjects and SSc patients affected by the diffuse form of the disease, were pooled, labeled with fluorochromes, and hybridized to 14,000 70 mer oligonucleotide microarrays. Genes were analyzed based on gene expression levels and categorized into different functional groups based on the description of the Gene Ontology (GO) consortium to identify statistically significant terms. Quantitative PCR was used to validate the array results. After data processing and application of the filtering criteria, the analyzable features numbered 6,724. About 3% of analyzable transcripts (199) were differentially expressed, 141 more abundantly and 58 less abundantly in SSc endothelial cells. Surprisingly, SSc endothelial cells over-express pro-angiogenic transcripts, but also show up-regulation of genes exerting a powerful negative control, and down-regulation of genes critical to cell migration and extracellular matrix-cytoskeleton coupling, all alterations that provide an impediment to correct angiogenesis. We also identified transcripts controlling haemostasis, inflammation, stimulus transduction, transcription, protein synthesis, and genome organization. An up-regulation of transcripts related to protein degradation and ubiquitination was observed in SSc endothelial cells. We have validated data on the main anti-angiogenesis-related genes by RT-PCR, western blotting, in vitro angiogenesis and immunohistochemistry. These observations indicate that microvascular endothelial cells of patients with SSc show abnormalities in a variety of genes that are able to account for defective angiogenesis

Aluminium blunts the proliferative response and increases apoptosis of cultured human cells: putative relationship to alzheimer's disease

Aluminium (Al) has been investigated as a neurotoxic substance. Al ranks among the potential environmental risk factors for Alzheimer's disease (AD). Epidemiological studies tested the relationship between Al in drinking water and AD, showing a significant correlation between elevated levels of monomeric Al in water and AD, although data to date remain inconclusive with respect to total Al. The aim of this study was to test whether or not Al exacerbates cellular toxicity mediated by the amyloid β (Aβ) peptide. We evaluated the role of Al in modulating programmed cell death (apoptosis) in human cell cultures. We used the osteosarcoma cell line monolayer (SaOs-2) to demonstrate that treatment of SaOs-2 cultures with the Aβ peptide mid-fragment (25 to 35) at nano M, followed by co-incubation with physiological concentrations of aluminium chloride, which release monomeric Al in solution, led to marked expression of caspase 3, but not caspase 9, key markers of the apoptotic process. The same experimental conditions were shown to blunt significantly the proliferative response of normal human peripheral blood mononuclear cells (PBMC) to phytohemagglutinin (PHA) stimulation. Our observations support the hypothesis that Al significantly impairs certain cellular immune responses, and confirm that Al-mediated cell toxicity may play an important role in AD