171 research outputs found
Deposits of disease-associated alpha-synuclein may be present in the dura mater in Lewy body disorders: implications for potential inadvertent transmission by surgery
Deposition of alpha-synuclein in the brain is a hallmark of Lewy body disorders. Alpha-synuclein has been considered to show prion-like properties. Prion diseases can be transmitted by the transplantation of cadaveric dura mater causing iatrogenic Creutzfeldt-Jakob disease. Recent observations of amyloid-β deposition in dural grafts support the seeding properties of amyloid-β. Here we assessed the presence of alpha-synuclein in dura mater samples as a potential transmissible seed source. We immunostained 32 postmortem dura mater samples; 16 cases with Lewy-body disorder (LBD) showing different pathology stages and 16 non-LBD cases for phosphorylated (Ser129) and disease-associated (5G4) alpha-synuclein. Disease-associated alpha-synuclein aggregates were identified in intradural nerve fibres and associated with a vessel in a single LBD-Braak stage 4 case. We conclude that alpha-synuclein is detectable, although rarely, in dura mater samples in patients with LBD. The risk of potential transmissibility of dural alpha-synuclein deserves assessment by complementary experimental studies
Diversity of Salmonella enterica serovar Derby isolated from pig, pork and humans in Germany
Salmonella enterica serovar Derby (S. Derby) is one of the most prevalent serovars in pigs in Europe and in the U.S. and ranks among the 10 most frequently isolated serovars in humans. Therefore, a set of 82 epidemiologically unrelated S. Derby strains isolated between 2006 and 2008 from pigs, pork and humans in Germany was selected and investigated in respect to the transmission of clonal groups of the serovar along the food chain. Various phenotypic and genotypic methods were applied and the pathogenicity and resistance gene repertoire was determined. Phenotypically 72% of the strains were susceptible to all 17 antimicrobials tested while the others were monoresistant to tetracycline or multi-resistant with different resistance profiles. Four major clonal groups were identified based on PFGE, sequence data of the virulence genes sopA, sopB and sopD, VNTR-locus STTR5 and MLST revealing also the new sequence type ST774. Thirty different PFGE profiles were detected resulting in four clusters representing the four groups. The pathogenicity gene repertoire of 32 representative S. Derby strains analyzed by microarray showed six types with differences in the Salmonella pathogenicity islands, pathogenicity genes on smaller islets or prophages and fimbriae coding genes. The pathogenicity gene repertoire of the predominant types PAT DE1 and DE2 were most similar to the ones of S. Paratyphi B (dT+, O5−) and to a minor degree to S. Infantis and S. Virchow PATs. Overall this study showed that in Germany currently one major S. Derby clone is frequently isolated from pigs and humans. Contaminated pork was identified as one vehicle and consequently is a risk for human health. To prevent this serovar from entering the food chain, control measurements should be applied at the farm level
Porcine model elucidates function of p53 isoform in carcinogenesis and reveals novel circTP53 RNA
Recent years have seen an increasing number of genetically engineered pig models of human diseases including cancer. We previously generated pigs with a modified TP53 allele that carries a Cre-removable transcriptional stop signal in intron 1, and an oncogenic mutation TP53R167H (orthologous to human TP53R175H) in exon 5. Pigs with the unrecombined mutant allele (flTP53R167H) develop mainly osteosarcoma but also nephroblastomas and lymphomas. This observation suggested that TP53 gene dysfunction is itself the key initiator of bone tumorigenesis, but raises the question which aspects of the TP53 regulation lead to the development of such a narrow tumour spectrum. Molecular analysis of p53 revealed the presence of two internal TP53 promoters (Pint and P2) equivalent to those found in human. Consequently, both pig and human express TP53 isoforms. Data presented here strongly suggest that P2-driven expression of the mutant R167H-Δ152p53 isoform (equivalent to the human R175H-Δ160p53 isoform) and its circular counterpart circTP53 determine the tumour spectrum and play a critical role in the malignant transformation in flTP53R167H pigs. The detection of Δ152p53 isoform mRNA in serum is indicative of tumorigenesis. Furthermore, we showed a tissue-specific p53-dependent deregulation of the p63 and p73 isoforms in these tumours. This study highlights important species-specific differences in the transcriptional regulation of TP53. Considering the similarities of TP53 regulation between pig and human, these observations provide useful pointers for further investigation into isoform function including the novel circTP53 in both the pig model and human patients.ISSN:0950-9232ISSN:1476-559
Nodal-Stage Classification in Invasive Lobular Breast Carcinoma: Influence of Different Interpretations of the pTNM Classification
Purpose Application of current nodal status classification is complicated in lobular breast carcinoma metastases. The aim of this study was to define the optimal interpretation of the pTNM classification in sentinel node (SN) -positive patients to select patients with limited or with a high risk of non-SN involvement. Patients and Methods SN metastases of 392 patients with lobular breast carcinoma were reclassified according to interpretations of the European Working Group for Breast Screening Pathology (EWGBSP) and guidelines by Turner et al, and the predictive power for non-SN involvement was assessed. Results Reclassification according to definitions of EWGBSP and Turner et al resulted in different pN classification in 73 patients (19%). The rate of non-SN involvement in the 40 patients with isolated tumor cells according to Turner et al and with micrometastases according to EWGBSP was 20%, which is comparable to the established rate for micrometastases. The rate of non-SN involvement in the 29 patients with micrometastases according to Turner et al and with macrometastases according to EWGBSP was 48%, which is comparable to the established rate for macrometastases. Therefore, the EWGBSP method to classify SN tumor load better reflected the risk of non-SN involvement than the Turner et al system. Conclusion Compared with the guidelines by Turner et al, the EWGBSP definitions better reflect SN metastatic tumor load and allow better differentiation between patients with lobular breast carcinoma who have a limited or a high risk of non-SN metastases. Therefore, we suggest using the EWGBSP definitions in these patients to select high-risk patients who may benefit from additional local and/or systemic therapy
Reproducibility and predictive value of scoring stromal tumour infiltrating lymphocytes in triple-negative breast cancer : a multi-institutional study
Several studies have demonstrated a prognostic role for stromal tumour infiltrating lymphocytes (sTILs) in triple-negative breast cancer (TNBC). The reproducibility of scoring sTILs is variable with potentially excellent concordance being achievable using a software tool. We examined agreement between breast pathologists across Europe scoring sTILs on H&E-stained sections without software, an approach that is easily applied in clinical practice. The association between sTILs and response to anthracycline-taxane NACT was also examined. Pathologists from the European Working Group for Breast Screening Pathology scored sTILs in 84 slides from 75 TNBCs using the immune-oncology biomarker working group guidance in two circulations. There were 16 participants in the first and 19 in the second circulation. Moderate agreement was achieved for absolute sTILs scores (intraclass correlation coefficient (ICC) = 0.683, 95% CI 0.601-0.767, p-value = 25% (kappa = 0.53) and for LPBC (kappa = 0.49), but poor for sTILs as 10% increments (kappa = 0.24). Increasing sTILs was significantly associated with an increased likelihood of a pathological complete response (pCR) on multivariable analysis. Increasing sTILs in TNBCs improves the likelihood of a pCR. However, inter-observer agreement is such that H&E-based assessment is not sufficiently reproducible for clinical application. Other methodologies should be explored, but may be at the cost of ease of application.Non peer reviewe
EphB2-dependent signaling promotes neuronal excitotoxicity and inflammation in the acute phase of ischemic stroke
Local cerebral hypoperfusion causes ischemic stroke while driving multiple cell-specific responses including inflammation, glutamate-induced neurotoxicity mediated via NMDAR, edema formation and angiogenesis. Despite the relevance of these pathophysiological mechanisms for disease progression and outcome, molecular determinants controlling the onset of these processes are only partially understood. In this context, our study intended to investigate the functional role of EphB2, a receptor tyrosine kinase that is crucial for synapse function and binds to membrane-associated ephrin-B ligands. Cerebral ischemia was induced in Ephb2−/− mice by transient middle cerebral artery occlusion followed by different times (6, 12, 24 and 48 h) of reperfusion. Histological, neurofunctional and transcriptome analyses indicated an increase in EphB2 phosphorylation under these conditions and attenuated progression of stroke in Ephb2−/− mice. Moreover, while infiltration of microglia/macrophages and astrocytes into the peri-infarct region was not altered, expression of the pro-inflammatory mediators MCP-1 and IL-6 was decreased in these mice. In vitro analyses indicated that binding of EphB2 to astrocytic ephrin-B ligands stimulates NF-κB-mediated cytokine expression via the MAPK pathway. Further magnetic resonance imaging of the Ephb2−/− ischemic brain revealed a lower level of cytotoxic edema formation within 6 h upon onset of reperfusion. On the mechanistic level, absence of neuronal EphB2 decreased the mitochondrial Ca2+ load upon specific activation of NMDAR but not during synaptic activity. Furthermore, neuron-specific loss of ephrin-B2 reduced the extent of cerebral tissue damage in the acute phase of ischemic stroke. Collectively, EphB2 may promote the immediate response to an ischemia-reperfusion event in the central nervous system by (i) pro-inflammatory activation of astrocytes via ephrin-B-dependent signaling and (ii) amplification of NMDA-evoked neuronal excitotoxicity
Evaluation der Maßnahmen zur Umsetzung der Vorschläge der Hartz-Kommission: Modul 1a, Neuausrichtung der Vermittlungsprozesse ; Bericht 2005 für das Bundesministerium für Wirtschaft und Arbeit
"Das Bundesministerium für Wirtschaft und Arbeit hat das Wissenschaftszentrum Berlin für Sozialforschung und das infas Institut für angewandte Sozialwissenschaft im September 2004 mit dem Evaluationsvorhaben Arbeitspaket 1, 'Modul 1a Neuausrichtung der Vermittlungsprozesse' beauftragt. Im Mittelpunkt steht die zentrale Frage, ob eine 'Verbesserung der Qualität und Schnelligkeit der Arbeitsvermittlung' nachgewiesen werden kann, die auf die Reformgesetze und -maßnahmen zurückzuführen sind. Implementationsanalysen untersuchen die Praxis der Agenturen bezüglich Bewerberdifferenzierung, Kundenmanagement, Aktivierung sowie Neuregelung von Zumutbarkeit und Sperrzeiten sowie die Vermittlungsdienstleistungen an Arbeitgeber. Auch der Einsatz vermittlungsnaher Dienstleistungen (Einschaltung Dritter nach Paragraph 37, Eingliederungsmaßnahmen durch Träger Paragraph 421i, Vermittlungsgutscheine, Personal-Service-Agenturen -PSA-) wird unter Umsetzungsgesichtspunkten untersucht. Über die Vermittlungsorganisation in Arbeitsgemeinschaften nach Paragraph 44b SGB II liegen erste Ergebnisse einer Grunderhebung vor. Die mittels Fallstudien, Dokumentenanalyse, schriftlichen und telefonischen Erhebungen gewonnenen Ergebnisse umreißen den Stand der Neuausrichtung der Vermittlungsprozesse. Die Wirkung der neu ausgerichteten Vermittlungsprozesse werden unter zwei Gesichtspunkten untersucht. Mittels multivariater Auswertungen wird zum einen die Wirkung des Kundenzentrums auf die Abgänge aus Arbeitslosigkeit geprüft. In einer instrumentenspezifisch angelegten Wirkungsanalyse wird zum anderen die Effektivität von vermittlungsnahen Dienstleistungen (Beauftragung Dritter, Beauftragung von Trägern mit Eingliederungsmaßnahmen, Personal Service Agenturen, Vermittlungsgutschein) analysiert und eine entsprechende Kosten-Nutzen-Bewertung vorgenommen. Der Bericht 2005 legt die Ergebnisse nach neun Monaten Laufzeit des Evaluationsvorhabens vor. Er ist vom Bemühen getragen, bereits belastbare Ergebnisse nach diesem vergleichsweise kurzen Zeitraum vorzulegen. Die Berichterstattung steht allerdings unter dem deutlichen Hinweis, dass die Organisation der Vermittlungsprozesse in den Agenturen und Arbeitsgemeinschaften weiterhin im Fluss ist. Die Implementationsstudien versuchen deswegen über die Momentaufnahme hinaus, grundlegende Konstruktionsfragen und -probleme aufzuzeigen. Wegen des vergleichsweise kurzen Beobachtungszeitraums seit Einführung der Kundenzentren und der vermittlungsnahen Dienstleistungen stehen auch die Wirkungsanalysen noch unter Vorbehalten." (Textauszug
Caffeine induces gastric acid secretion via bitter taste signaling in gastric parietal cells
Caffeine, generally known as a stimulant of gastric acid secretion (GAS), is a bitter-tasting compound that activates several taste type 2 bitter receptors (TAS2Rs). TAS2Rs are expressed in the mouth and in several extraoral sites, e.g., in the gastrointestinal tract, in which their functional role still needs to be clarified. We hypothesized that caffeine evokes effects on GAS by activation of oral and gastric TAS2Rs and demonstrate that caffeine, when administered encapsulated, stimulates GAS, whereas oral administration of a caffeine solution delays GAS in healthy human subjects. Correlation analysis of data obtained from ingestion of the caffeine solution revealed an association between the magnitude of the GAS response and the perceived bitterness, suggesting a functional role of oral TAS2Rs in GAS. Expression of TAS2Rs, including cognate TAS2Rs for caffeine, was shown in human gastric epithelial cells of the corpus/fundus and in HGT-1 cells, a model for the study of GAS. In HGT-1 cells, various bitter compounds as well as caffeine stimulated proton secretion, whereby the caffeine-evoked effect was (i) shown to depend on one of its cognate receptor, TAS2R43, and adenylyl cyclase; and (ii) reduced by homoeriodictyol (HED), a known inhibitor of caffeine’s bitter taste. This inhibitory effect of HED on caffeine-induced GAS was verified in healthy human subjects. These findings (i) demonstrate that bitter taste receptors in the stomach and the oral cavity are involved in the regulation of GAS and (ii) suggest that bitter tastants and bitter-masking compounds could be potentially useful therapeutics to regulate gastric pH
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