114 research outputs found
Chronological evidence for a pre-Minoan age of pyroclastic deposits on Anafi Island, Cyclades, Greece
No full textPyroclastic deposits on Anafi Island, Cyclades, Greece, were initially related to the Minoan eruption (1613 BC), but later geochemical studies favored an older chronology that points at the Lower Pumice eruption of Santorini (172 ka). Here we attempt through OSL dating to provide a minimum age by dating sand-sized quartz from colluvium overlying the deposits. The chronological results excluded the possibility of being Minoan. © 2019, Springer Nature Switzerland AG
Anti-GalNAcβ : a novel anti-glycan autoantibody associated with pregnancy loss in women with antiphospholipid syndrome and in a mouse experimental model
No full textOBJECTIVES: We evaluated the presence of anti-glycan antibodies (aGA) in patients with antiphospholipid syndrome (APS), and associations between aGA and clinical features of the disease.
METHODS: Sera from APS patients and healthy controls were analyzed for aGA levels by ELISA. Analysis of the association of specific aGA with clinical manifestations of APS was performed. Selected aGA were affinity-purified and injected intravenously into naive mice which were tested for fetal loss. Matrigel invasion assay was performed for detection of choriocarcinoma cells (JAR) invasion and proliferation in the presence of selected aGA. Culture fluid of JAR invasion assays was analyzed for the presence of MMP2 and MMP9.
RESULTS: High levels of several aGA were found in APS sera, of which anti-GalNAc-β was significantly associated with recurrent pregnancy loss. Naive mice infused intravenously with anti-GalNAc-β developed increased fetal loss. Anti-GalNAc-β significantly inhibited the in-vitro percentage of JAR invasiveness and the secretion of MMP2 and MMP9 by human JAR cells.
CONCLUSIONS: APS sera contain significant levels of aGA directed against several glycans. Anti-GalNAc-β Ab is specifically associated with recurrent pregnancy loss both in human patients and experimental mouse model. The pathogenic effects of anti-GalNAc-β include inhibition of JAR cells invasiveness accompanied by decreased MMP2 and MMP9 secretio
Pumice deposits of the Santorini Lower Pumice 2 eruption on Anafi island, Greece: Indications for a Plinian event of exceptional magnitude
No full textIsolated patches of Santorini pumice deposits are analysed from the non-volcanic island of Anafi at a distance of 31–38 km east from the centre of the Santorini caldera. The deposits are Plinian fall profiles with a primary thickness at this distance of 1.2–1.5 m and MP (maximum pumice) and ML (maximum lithic) diameters of 5 and 4 cm, respectively. The characteristic profile sequence of the analysed Anafi deposits corresponds perfectly with the Plinian sequence of the Lower Pumice 2 (LP2) profiles on Thera, the main island of the Santorini group, with the sub-divisions into LP2-A2-1, LP2-A2-2 and LP2-A3. Pumice glass chemistry, phenocryst assemblage and the significant content of grey cauliform scoriae make the compositional correlation with the Plinian LP2 eruption of Santorini unambiguous. With the new identification of LP2 deposits on Anafi, together with an ~ 4–5 times greater thickness in the main axis of dispersal of the proximal Plinian LP2 deposits compared to the Minoan fallout on Thera, the Plinian opening phase of the 172 ka LP2 eruption (LP2-A) is regarded by far as the most voluminous of all Plinian eruptive phases on Santorini
ANAFILAKSIJA - PRISTUP LIJEČENJU
No full textAnafi laksija je akutna, generalizirana, potencijalno vitalno ugrožavajuća reakcija preosjetljivosti. Naziv alergijska anafi laksija
upotrebljava se za imunološku reakciju koja je posredovana IgE, IgG protutijelima ili imunim kompleksima. Nealergijska anafi
laksija nastaje bez posredovanja imunosnog mehanizma uslijed izravne degranulacije mastocita. Incidencija anafi laksije u
odraslih u Europi, prema izvješću Europske akademije alergologije i kliničke imunologije, procjenjuje se na 1,5 - 7,9/100 000,
dok za djecu dostupni podaci uvelike variraju. Najčešći uzročnici anafi laksije u djece su nutritivni alergeni (jaje, kravlje mlijeko,
kikiriki, orašasti plodovi, bijela riba), potom ubodi insekata te lijekovi. Pravovremeno prepoznavanje simptoma, prekidanje
dodira bolesnika s alergenom te pravodobna primjena medikamentozne terapije ključni su za dobar ishod liječenja. Adrenalin,
prema svim smjernicama, predstavlja prvu liniju liječenja anafi laksije i njegovu primjenu ne treba odgađati. Primjenjuje se
intramuskularno u srednju trećinu lateralne strane bedra (m. vastus lateralis) u dozi od 0,01 ml/kg. U slučaju perzistiranja
simptoma, ponavlja se primjena adrenalina nakon pet minuta. S obzirom na povećanu vaskularnu propusnost i posljedičnu
ekstravazaciju tekućine, tijekom anafi laksije potrebno je što prije postaviti venski put te započeti primjenu kristaloidnih otopina
u dozi 500 - 1000 mL za odrasle te 10 - 20 mL/kg za djecu, u bolusu. Također, u svih pacijenata, potrebno je primijeniti
visoki protok kisika putem maske. Prema najnovijim smjernicama ne preporučuje se više rutinska primjena kortikosteroida.
Postoji vrlo malo dokaza o njihovoj učinkovitosti u sprečavanju protrahiranih i bifazičnih reakcija. Međutim, primjena kortikosteroida
može biti korisna u pacijenata s anafi laksijom kod kojih akutna egzacerbacija astme doprinosi težini kliničke slike.
Simptomi anafi laksije i teške akutne egzacerbacije astme mogu biti jednaki, stoga je nužno kod svih pacijentima koji se prezentiraju
kliničkom slikom teške bronhoopstrukcije, uz anamnestički podatak o mogućoj izloženosti alergenu, prvo primijeniti
adrenalin, a potom ordinirati inhalaciju salbutamola ili ipratropij bromida. Primjena antihistaminika se ne preporučuje
tijekom inicijalnog zbrinjavanja anafi laksije. Antihistaminici se mogu primijeniti za liječenje kožnih simptoma, ali njihova primjena
ne smije odgoditi primjenu adrenalina. Kod pacijenata s dobrim odgovorom unutar 5 - 10 minuta na jednokratnu terapiju
adrenalinom, dobivenu unutar 30 minuta od reakcije, moguć je otpust nakon opservacije u trajanju od minimalno dva
sata. U slučaju primjene dvije doze adrenalina te anamnestičkog podatka o prethodnom bifazičnom tijeku reakcije, potrebna
je opservacija od minimalno šest sati. Pacijente je potrebno opservirati tijekom najmanje 12 sati ako je bilo potrebno primijeniti
više od dvije doze adrenalina, ako imaju nekontroliranu astmu, ako je reakcija uključivala tešku bronhoopstrukciju, ako
postoji mogućnost daljnje apsorpcije alergena (npr. kod ingestije sporo oslobađajućih lijekova) ili ako je reakcija nastupila tijekom
noći a pacijent živi u područjima bez dostupne medicinske skrbi. Profi laktički, svim pacijentima s poviješću i predispozicijom
za anafi laksiju, potrebno je prepisati autoinjektor adrenalina
Expanding extension, subsidence and lateral segmentation within the Santorini - Amorgos basins during Quaternary: Implications for the 1956 Amorgos events, central - south Aegean Sea, Greece
No full textNew bathymetric and seismic reflection data from the Santorini–Amorgos Tectonic Zone in the southern Cyclades have been analysed and a description of the morphology and tectonic structure of the area has been presented. The basins of Anhydros, Amorgos and Santorini–Anafi have been distinguished together with the intermediate Anhydros Horst within the NE-SW oriented Santorini–Amorgos Tectonic Zone which has a length of 60–70 km and a width of 20–25 km. The basins represent tectonic grabens or semi-grabens bordered by the active marginal normal faults of Santorini–Anafi, Amorgos, Ios, Anhydros and Astypalaea. The Santorini–Anafi, Amorgos and Ios marginal faults have their footwall towards the NW where Alpine basement occurs in the submarine scarps and their hangingwall towards the southeast, where the Quaternary sediments have been deposited with maximum thickness of 700 m. Six sedimentary Units 1–6 have been distinguished in the stratigraphic successions of the Santorini–Anafi and the western Anhydros Basin whereas in the rest area only the upper four Units 3–6 have been deposited. This shows the expansion of the basin with subsidence during the Quaternary due to ongoing extension in a northwest-southeast direction. Growth structures are characterized by different periods of maximum deformation as this is indicated by the different sedimentary units with maximum thickness next to each fault. Transverse structures of northwest-southeast direction have been identified along the Santorini–Amorgos Tectonic Zone with distinction of the blocks/segments of Santorini, Anhydros/Kolumbo, Anhydros islet and Amorgos. Recent escarpments with 7–9 m offset observed along the Amorgos Fault indicate that this was activated during the first earthquake of the 7.5 magnitude 1956 events whereas no recent landslide was found in the area that could be related to the 1956 tsunami. © 2017 Elsevier B.V
Molecular interactions of the Src homology 2 domain protein Shb with phosphotyrosine residues, tyrosine kinase receptors and Src homology 3 domain proteins
No full textThe molecular interactions of the Src homology 2 (SH2) domain and the N-terminal proline-rich sequence motifs (pro-1 to pro-5) of the SH2 protein Shb with other components were presently characterised. Using a degenerate phosphopeptide library the preferred binding site for the Shb SH2 domain was determined to pTyr-Thr/Val/Ile-X-Leu at positions +1 to +3 relative the phosphotyrosine residue. Experiments with competing peptides and platelet-derived growth factor (PDGF) beta-receptor mutants with Y to F substitutions in autophosphorylation sites revealed multiple binding sites for the Shb SH2 domain in the receptor. The Shb SH2 domain also binds to in vitro phosphorylated fibroblast growth factor receptor-1 (FGFR-1) mainly through position Y776. The receptor experiments suggest that other residues besides the +1 to +3 positions may also be of significance for Shb binding. The pro-4/pro-5 motif of Shb binds in vitro particularly well to the Src, p85 alpha PI3-kinase and Eps8 SH3 domains expressed as GST fusion proteins. However, the GST-SH3 domain fusion proteins tested bind in vitro to peptides corresponding to the pro-1 to pro-5 motifs of Shb with low affinity and selectivity, suggesting that sequences outside the core proline motif may also be important for Shb-SH3 domain interactions. In vivo association between Shb-SH3 domain proteins v-Src and Eps8 was detected by coimmunoprecipitation. PDGF treatment did not affect the association between Eps8 and Shb. The data suggest that Shb is an adaptor protein linking SH3 domain proteins to tyrosine kinases or other tyrosine phosphorylated proteins
Expanding extension, subsidence and lateral segmentation within the Santorini - Amorgos basins during Quaternary: Implications for the 1956 Amorgos events, central - south Aegean Sea, Greece
No full textNew bathymetric and seismic reflection data from the Santorini–Amorgos Tectonic Zone in the southern Cyclades have been analysed and a description of the morphology and tectonic structure of the area has been presented. The basins of Anhydros, Amorgos and Santorini–Anafi have been distinguished together with the intermediate Anhydros Horst within the NE-SW oriented Santorini–Amorgos Tectonic Zone which has a length of 60–70 km and a width of 20–25 km. The basins represent tectonic grabens or semi-grabens bordered by the active marginal normal faults of Santorini–Anafi, Amorgos, Ios, Anhydros and Astypalaea. The Santorini–Anafi, Amorgos and Ios marginal faults have their footwall towards the NW where Alpine basement occurs in the submarine scarps and their hangingwall towards the southeast, where the Quaternary sediments have been deposited with maximum thickness of 700 m. Six sedimentary Units 1–6 have been distinguished in the stratigraphic successions of the Santorini–Anafi and the western Anhydros Basin whereas in the rest area only the upper four Units 3–6 have been deposited. This shows the expansion of the basin with subsidence during the Quaternary due to ongoing extension in a northwest-southeast direction. Growth structures are characterized by different periods of maximum deformation as this is indicated by the different sedimentary units with maximum thickness next to each fault. Transverse structures of northwest-southeast direction have been identified along the Santorini–Amorgos Tectonic Zone with distinction of the blocks/segments of Santorini, Anhydros/Kolumbo, Anhydros islet and Amorgos. Recent escarpments with 7–9 m offset observed along the Amorgos Fault indicate that this was activated during the first earthquake of the 7.5 magnitude 1956 events whereas no recent landslide was found in the area that could be related to the 1956 tsunami
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