11 research outputs found
ANCIENT MINING LANDSCAPES AND HABITATIVE SCENERIES IN THE URBAN AREA OF CENTOCELLE: GEOMATIC APPLICATIONS FOR THEIR IDENTIFICATION, MEASUREMENT, DOCUMENTATION AND MONITORING
This study, focused on the Archaeological Park of Centocelle, was carried out to test the functionality of different geomatic products for the identification and monitoring of complex archaeological evidences in urban areas. The method proposes a better knowledge of the archaeological context as a tool to favour a better protection, allowing the establishment of limits to urban enlargement in areas of respect. The test area is chosen because of the combined presence of hypogeal evidences related to Roman and pre-Roman exploitation of local litotypes and for the dense presence of archaeological vestiges at its surface, related to the inhabitation function of the zone in a period contemporaneous to the beginning of the quarrying activities. The methods used are the digital photogrammetry, 3D modelling, remote sensing interpretation and digital cartography. The protocol is then customized for the peculiarities of the area under study, considering both the underground structures and the ones at the surface. Archaeological features are identified by processing optical and SAR dataset to enhance the contrast of archaeological features from the background. Historical and recent DSM have been then compared to evaluate the evolutions of local topography. Concerning the study of the subterranean quarrying system in the area, a 3D model of one gallery was produced, with the aim to understand the type of ancient exploitation. A DTM of the toolmarks was then produced to understand the technological skills used for the exploitation of the local tuff and used as an indirect proof for chronological interpretation. A final trial of PSInSAR was addressed to test the method for monitoring the hypogeal levels. Several field prospections were executed, in order to first set the method properly and then validate the results
PMCA-Based Detection of Prions in the Olfactory Mucosa of Patients With Sporadic CreutzfeldtâJakob Disease
Sporadic Creutzfeldt-Jakob disease (sCJD) is a rare neurodegenerative disorder caused by the conformational conversion of the prion protein (PrPC) into an abnormally folded form, named prion (or PrPSc). The combination of the polymorphism at codon 129 of the PrP gene (coding either methionine or valine) with the biochemical feature of the proteinase-K resistant PrP (generating either PrPSc type 1 or 2) gives rise to different PrPSc strains, which cause variable phenotypes of sCJD. The definitive diagnosis of sCJD and its classification can be achieved only post-mortem after PrPSc identification and characterization in the brain. By exploiting the Real-Time Quaking-Induced Conversion (RT-QuIC) assay, traces of PrPSc were found in the olfactory mucosa (OM) of sCJD patients, thus demonstrating that PrPSc is not confined to the brain. Here, we have optimized another technique, named protein misfolding cyclic amplification (PMCA) for detecting PrPSc in OM samples of sCJD patients. OM samples were collected from 27 sCJD and 2 genetic CJD patients (E200K). Samples from 34 patients with other neurodegenerative disorders were included as controls. Brains were collected from 26 sCJD patients and 16 of them underwent OM collection. Brain and OM samples were subjected to PMCA using the brains of transgenic mice expressing human PrPC with methionine at codon 129 as reaction substrates. The amplified products were analyzed by Western blot after proteinase K digestion. Quantitative PMCA was performed to estimate PrPSc concentration in OM. PMCA enabled the detection of prions in OM samples with 79.3% sensitivity and 100% specificity. Except for a few cases, a predominant type 1 PrPSc was generated, regardless of the tissues analyzed. Notably, all amplified PrPSc were less resistant to PK compared to the original strain. In conclusion, although the optimized PMCA did not consent to recognize sCJD subtypes from the analysis of OM collected from living patients, it enabled us to estimate for the first time the amount of prions accumulating in this biological tissue. Further assay optimizations are needed to faithfully amplify peripheral prions whose recognition could lead to a better diagnosis and selection of patients for future clinical trials
Metal alloys, matrix inclusions and manufacturing techniques of Moinhos de Golas collection (North Portugal): a study by micro-EDXRF, SEMâEDS, optical microscopy and X-ray radiography
"Article:820"A collection of 35 metallic artefacts comprising
various typologies, some of which can be attributed to the
Bronze Age and others to later periods, were studied to
provide detailed information on elemental composition,
manufacturing techniques and preservation state. Elemental
analysis by micro-EDXRF and SEMâEDS was performed
to investigate the use of different alloys and to
study the presence of microstructural heterogeneities, as
inclusions. X-ray radiography, optical microscopy and
SEMâEDS were used to investigate manufacturing techniques
and degradation features. Results showed that most
of the artefacts were produced in a binary bronze alloy
(CuâSn) with 10â15 wt% Sn and a low concentration of
impurities. Other artefacts were produced in copper or in
brass, the latest with varying contents of Zn, Sn and Pb. A
variety of inclusions in the metal matrices were also found,
some related to specific types of alloys, as (CuâNi)S2 in
coppers, or ZnS in brasses. Microstructural observations
revealed that the majority of the artefacts were subjected to
cycles of thermomechanical processing after casting, being
evident that among some artefacts different parts were
subjected to distinct treatments. The radiographic images
revealed structural heterogeneities related to local corrosion
processes and fissures that seem to have developed in
wear-tension zones, as in the handle of some daggers.
Radiographic images were also useful to detect the use of
different materials in one particular brass artefact, revealing
the presence of a possible CuâSn solder.This work was funded by FEDER funds through
the COMPETE 2020 Programme and National Funds through FCTâ
Fundação para a CiĂȘncia e a Tecnologia under the project UID/CTM/
50025/2013 to CENIMAT/I3N. C2
TN/IST authors gratefully
acknowledge the FCT support through the UID/Multi/04349/2013
project. EF acknowledges FCT for the grant SFRH/BPD/97360/2013.
JF acknowledge FCT for the grant SFRH/BD/65143/2009. Part of this
project has been done in the framework of the FCT project ENARDAS
(PTDC/HISARQ/112983/2009).info:eu-repo/semantics/publishedVersio
Bifunctional carbazole derivatives for simultaneous therapy and fluorescence imaging in prion disease murine cell models
Prion diseases are characterized by the self-assembly of pathogenic misfolded scrapie isoforms (PrPSc) of the cellular prion protein (PrPC). In an effort to achieve a theranostic profile, symmetrical bifunctional carbazole derivatives were designed as fluorescent rigid analogues of GN8, a pharmacological chaperone that stabilizes the native PrPC conformation and prevents its pathogenic conversion. A focused library was synthesized via a four-step route, and a representative member was confirmed to have native fluorescence, including a band in the near-infrared region. After a cytotoxicity study, compounds were tested on the RML-infected ScGT1 neuronal cell line, by monitoring the levels of protease-resistant PrPSc. Small dialkylamino groups at the ends of the molecule were found to be optimal in terms of therapeutic index, and the bis-(dimethylaminoacetamido)carbazole derivative 2b was selected for further characterization. It showed activity in two cell lines infected with the mouse-adapted RML strain (ScGT1 and ScN2a). Unlike GN8, 2b did not affect PrPC levels, which represents a potential advantage in terms of toxicity. Amyloid Seeding Assay (ASA) experiments showed the capacity of 2b to delay the aggregation of recombinant mouse PrP. Its ability to interfere with the amplification of the scrapie RML strain by Protein Misfolding Cyclic Amplification (PMCA) was shown to be higher than that of GN8, although 2b did not inhibit the amplification of human vCJD prion. Fluorescent staining of PrPSc aggregates by 2b was confirmed in living cells. 2b emerges as an initial hit compound for further medicinal chemistry optimization towards strain-independent anti-prion compounds