201 research outputs found

    Revision of the Upper Cretaceous ammonite fauna of the Bakony Mountains (Hungary)

    Get PDF
    A revision of the ammonites from the Bakony Mountains (Hungaty) based on collections of the Geological Institute of Hungary (MAFI) in Budapest, revealed the following sequence of faunas. The youngest Campanian ammonites from the South Bakony are three specimens ofPachydiscus (P.)praecolligatus COLLIGNON, 1955 from the Siimeg area; this is a typical Campanian species. Two specimens of former "Lower Maastrichtian Pachydiscus neubergicus (HAUER)" from Haraszt quany have been re-determined as Early Campanian Eupachydiscus levyi (GROSS OUVRE, 1894). The fragmentary specimen of Mortoniceras sp. has been determined as Texanites (Texanites) sp. from the Upper Santonian. Two ammonite zones can be recognised for these sequences: Texanites sp. (Santonian) and Eupachydiscus levyi (Lower Campanian)

    Quantification of serotonin and eight of its metabolites in plasma of healthy volunteers by mass spectrometry.

    Get PDF
    Serotonin is transformed into melatonin under the control of the light/dark cycle, representing a cornerstone of circadian rhythmicity. Serotonin also undergoes extensive metabolism to produce 5-hydroxyindoleacetic acid (5-HIAA), a biomarker for the diagnosis and monitoring of serotonin secreting neuroendocrine tumors (NETs). While serotonin, melatonin and their metabolites are part of an integrated comprehensive system, human observations about their respective plasma concentrations are still limited. We report here for the first time a multiplex UHPLC-MS/MS assay for the quantification of serotonin, 5-HIAA, 5-hydroxytryptophol (5-HTPL), N-acetyl-serotonin (NAS), Mel, 6-OH-Mel, 5-methoxytryptamine (5-MT), 5-methoxytryptophol (5-MTPL), and 5-methoxyindoleacetic acid (5-MIAA) in human plasma. Analytes were extracted by protein precipitation and solid phase extraction. Plasma concentrations for these analytes were determined in 102 healthy volunteers. The LLOQ of the assay ranges from 2.2 nM for serotonin to 1.0 pM for 6-OH-Mel. This sensitivity enables the quantification of circulating serotonin, 5-HIAA, NAS, Mel, and 5-MIAA, even at their lowest diurnal concentrations. This assay will enable specific, precise and accurate measurement of serotonin, Mel and their metabolites to draw a detailed picture of this complex pineal metabolism, allowing a dynamic understanding of these pathways and providing promising biomarkers and a metabolic signature for serotonin-secreting NETs

    Preparation and characterization of lapatinib-loaded PVP nanofiber amorphous solid dispersion by electrospinning

    Get PDF
    Lapatinib-loaded polyvinylpyrrolidone-based nanofibrous solid dispersions were prepared by electrospinning in order to enhance the aqueous solubility and dissolution rate of the anticancer drug. The prepared nanofibers were characterized by smooth-surfaced, homogenous filaments with average diameters of 462±160 nm determined by scanning electron microscopy. The crystalline to amorphous transition of the active ingredient was confirmed by differential scanning calorimetry, while Raman spectroscopy showed that amorphous lapatinib was uniformly distributed in the fibrous structures. Gas chromatographic analyses revealed that residual solvents in the nanofiber mats were below the ICH Guideline Q3C recommended limits, namely ethanol 10.9±2.3 ppm (recommended limit 5000 ppm) and dimethyl formamide 780±56 ppm (recommended limit 880 ppm). Determination of drug content and in vitro dissolution studies were performed in order to observe the influence of electrospinning on the drug release characteristics of the product obtained. The lapatinib content in the nanofibers were measured to be 16.76±0.11 w/w%, whereas the dissolution study at pH 6.8 indicated a rapid disintegration of the nanofibrous mats, releasing ~70% of the drug loading under 5 minutes compared to the ~0.05% dissolution of the neat lapatinib ditosylate. The results confirm the applicability of electrospinning for the improvement of physicochemical characteristics of the poorly bioavailable anticancer agent

    Cytokeratin 7 and 20 staining for the diagnosis of lung and colorectal adenocarcinoma

    Get PDF
    The origin of metastatic adenocarcinoma lesions can sometimes be difficult to diagnose. The objectives of our study were to establish the cytokeratin staining pattern of primary and metastatic lung and colorectal adenocarcinomas, and to determine if this helps to identify the site of origin of metastatic lesions. We reviewed a total of 102 tissue samples from patients in our tumour registry, with either primary or metastatic lung or colorectal adenocarcinoma. Tissue sections were stained for cytokeratin 7 and 20 and read as positive or negative for staining. Clinical and radiologic information was reviewed from computerised charts. The cytokeratin 7+/cytokeratin 20− pattern characterised 96% (29 out of 30) of primary and 95% (21 out of 22) of metastatic lung adenocarcinomas. All the primary (26), and 88% (21 out of 24) of metastatic colorectal adenocarcinomas stained cytokeratin 7−/cytokeratin 20+. Samples from a variety of metastatic sites were evaluated for cytokeratin 7 and 20 staining. Out of the 102 samples, in 95% (97 out of 102) of the cases, the cytokeratin 7 and cytokeratin 20 staining pattern characterised and differentiated between lung and colorectal adenocarcinoma. Primary and metastatic lung adenocarcinomas show a cytokeratin 7+/cytokeratin 20− staining pattern, while colorectal adenocarcinomas stain cytokeratin 7−/cytokeratin 20+. Cytokeratin staining is helpful in the diagnostic differentiation of metastatic lesions from these two common primaries, and assists in determining the site of origin of metastatic lesions

    History and Class Consciousness 2.0: Georg Lukács in the age of digital capitalism and big data

    Get PDF
    This paper discusses the relevance of Georg Lukács’ 1923 book History and Class Consciousness in the context of digital capitalism. It does so by analysing how Lukács’ concepts of the dialectic of subject and object, ideology, reification, reified consciousness matter today in the context of big data and digital capitalism. The essay shows that History and Class Consciousness’ critique of reification, ideology, and reified consciousness remains highly topical in the age of digital capitalism and big data. Lukács’ analysis allows us to critically analyse how social media, big data, and various other Internet technologies are used as tools of reification. At the same time, Lukács reminds us that only human praxis can establish alternatives

    Common Man, Society and Religion in the 16th century/Gemeiner Mann, Gesellschaft und Religion im 16. Jahrhundert

    Get PDF
    Der zweisprachige Sammelband vereinigt zum Teil bahnbrechende Ergebnisse einer interdisziplinären Forschungstagung, deren Beiträge sozial-, wirtschafts-, kultur- und kirchengeschichtliche Aspekte der Frühneuzeit im Karpatenbogen aufgreifen. Basierend auf vielfach erstmals ausgewerteten Quellen bearbeiten die Beiträge aktuelle Fragestellungen und Forschungshorizonte zur Interdependenz von sozialen, ökonomischen, kulturellen und religiösen Phänomenen im Karpatenbogen der Frühen Neuzeit, in dem die Osmanen der international dominante politische Faktor wurden. Transformationsprozesse wurden angestoßen durch Bevölkerungs- und Militärbewegungen, ökonomische, politische und religiös-mentale Umwälzungen, die zwischen opportunistischer Anpassung und rebellierendem Widerstand oszillierten und entsprechende politische Maßnahmen und Gegenreaktionen hervorriefen. Dabei wird die bislang geltende Forschungsmeinung zur Toleranzgeschichte Siebenbürgens in Frage gestellt und völlig neu bewertet

    Common Man, Society and Religion in the 16th century/Gemeiner Mann, Gesellschaft und Religion im 16. Jahrhundert

    Get PDF
    Der zweisprachige Sammelband vereinigt zum Teil bahnbrechende Ergebnisse einer interdisziplinären Forschungstagung, deren Beiträge sozial-, wirtschafts-, kultur- und kirchengeschichtliche Aspekte der Frühneuzeit im Karpatenbogen aufgreifen. Basierend auf vielfach erstmals ausgewerteten Quellen bearbeiten die Beiträge aktuelle Fragestellungen und Forschungshorizonte zur Interdependenz von sozialen, ökonomischen, kulturellen und religiösen Phänomenen im Karpatenbogen der Frühen Neuzeit, in dem die Osmanen der international dominante politische Faktor wurden. Transformationsprozesse wurden angestoßen durch Bevölkerungs- und Militärbewegungen, ökonomische, politische und religiös-mentale Umwälzungen, die zwischen opportunistischer Anpassung und rebellierendem Widerstand oszillierten und entsprechende politische Maßnahmen und Gegenreaktionen hervorriefen. Dabei wird die bislang geltende Forschungsmeinung zur Toleranzgeschichte Siebenbürgens in Frage gestellt und völlig neu bewertet

    Peptide Bond Distortions from Planarity: New Insights from Quantum Mechanical Calculations and Peptide/Protein Crystal Structures

    Get PDF
    By combining quantum-mechanical analysis and statistical survey of peptide/protein structure databases we here report a thorough investigation of the conformational dependence of the geometry of peptide bond, the basic element of protein structures. Different peptide model systems have been studied by an integrated quantum mechanical approach, employing DFT, MP2 and CCSD(T) calculations, both in aqueous solution and in the gas phase. Also in absence of inter-residue interactions, small distortions from the planarity are more a rule than an exception, and they are mainly determined by the backbone ψ dihedral angle. These indications are fully corroborated by a statistical survey of accurate protein/peptide structures. Orbital analysis shows that orbital interactions between the σ system of Cα substituents and the π system of the amide bond are crucial for the modulation of peptide bond distortions. Our study thus indicates that, although long-range inter-molecular interactions can obviously affect the peptide planarity, their influence is statistically averaged. Therefore, the variability of peptide bond geometry in proteins is remarkably reproduced by extremely simplified systems since local factors are the main driving force of these observed trends. The implications of the present findings for protein structure determination, validation and prediction are also discussed
    corecore