377 research outputs found
Моделирование процесса каплеобразования при промысловой подготовке нефти
In subgroups of a New Zealand obese mouse-derived back-cross population with defined aberrations of glucose ho-meostasis, a comprehensive study of the hepatic expression of cytochrome P450 and glutathione S-transferase was per-formed. Three patterns of alterations in response to insulin resistance (normoglycemia/hyperinsulinemia) or diabetes (hy-perglycemia/hypoinsulinemia) were observed: mRNA levels of Cyp2b9, Cyp3a16, Cyp4a14, and Gstt2 as assessed by North-ern- and dot-blot analysis were increased markedly in liver from diabetic mice with no or only a slight increase in insulin resistant mice. Western-blot analysis detected the corresponding changes of the CYP2B and CYP4A proteins. In contrast, ex-pression of Cyp2c22, Cyp2c29, and Cyp2c40 was reduced in diabetic, but normal in insulin resistant mice. These alteration
Evaluation of a video-based Internet intervention as preparation for inpatient psychosomatic rehabilitation: study protocol for a randomized controlled trial
SPIRIT checklist. Overview of important items of a clinical trial and their placement in the manuscript. (DOC 122 kb
Internal gamma gamma-opacity in Active Galactic Nuclei and the consequences for the TeV observations of M87 and Cen A
Low Luminosity Active Galactic Nuclei (LLAGNs) possess the characteristic
features of more luminous Active Galactic Nuclei (AGNs) but exhibit a much
lower nuclear Halpha luminosity than their more luminous counterparts. M87 (NGC
4486) and Centaurus A (NGC 5128, CenA) are well-studied nearby LLAGNs. As an
additional feature they show gamma-radiation up to TeV (10^{12}eV) energies,
but the origin of this radiation is not resolved. The coincident observation of
a radio and TeV flare in M87 suggests that the TeV radiation is produced within
around 50-100 gravitational radii of the central supermassive black hole,
depending on the assumed value of the mass of the black hole. Strong radiation
fields can be produced in the central region of an (LL)AGN, e.g., by the
accretion flow around the black hole, the jet plasma, or stars closely orbiting
the black hole. These radiation fields can lead to the absorption of emitted
TeV photons, and in fact high optical depths of such fields can make TeV
detection from inner regions impossible. In this paper we consider the
accretion flow around the black hole as the most prominent source for such a
radiation field and we accordingly calculate the probability for absorption of
TeV photons produced near the black holes in M87 and CenA assuming a low
luminosity Shakura-Sunyaev Disk (SSD). We find that the results are very
different for between the two LLAGNs. While the inner region of M87 is
transparent for TeV radiation up to 15TeV, the optical depth in CenA is >> 1,
leading to an absorption of TeV photons that might be produced near the central
black hole. These results imply either that the TeV gamma production sites and
processes are different for both sources, or that LLAGN black holes do not
accrete (at least only) in form of a low luminosity SSD.Comment: accepted for publication in Ap
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Foundations of plasma standards
The field of low-temperature plasmas (LTPs) excels by virtue of its broad intellectual diversity, interdisciplinarity and range of applications. This great diversity also challenges researchers in communicating the outcomes of their investigations, as common practices and expectations for reporting vary widely in the many disciplines that either fall under the LTP umbrella or interact closely with LTP topics. These challenges encompass comparing measurements made in different laboratories, exchanging and sharing computer models, enabling reproducibility in experiments and computations using traceable and transparent methods and data, establishing metrics for reliability, and in translating fundamental findings to practice. In this paper, we address these challenges from the perspective of LTP standards for measurements, diagnostics, computations, reporting and plasma sources. This discussion on standards, or recommended best practices, and in some cases suggestions for standards or best practices, has the goal of improving communication, reproducibility and transparency within the LTP field and fields allied with LTPs. This discussion also acknowledges that standards and best practices, either recommended or at some point enforced, are ultimately a matter of judgment. These standards and recommended practices should not limit innovation nor prevent research breakthroughs from having real-time impact. Ultimately, the goal of our research community is to advance the entire LTP field and the many applications it touches through a shared set of expectations
Safety of direct oral anticoagulants in patients with advanced liver disease
BACKGROUND & AIMS: While direct oral anticoagulants (DOACs) are increasingly used in patients with liver disease, safety data especially in advanced chronic liver disease (ACLD) are limited. METHODS: Liver disease patients receiving DOAC treatment (ACLD: n = 104; vascular liver disease: n = 29) or vitamin K antagonists (VKA)/low‐molecular‐weight heparin (LMWH; ACLD: n = 45; vascular: n = 13) between January 2010 and September 2020 were retrospectively included. Invasive procedures and bleeding events were recorded. Calibrated anti‐Xa peak levels and thrombomodulin‐modified thrombin generation assays (TM‐TGAs) were measured in a subgroup of 35/28 DOAC patients. RESULTS: Among patients receiving DOAC, 55 (41.3%) had advanced liver dysfunction (Child‐Pugh‐stage [CPS] B/C) and 66 (49.6%) had experienced decompensation. Overall, 205 procedures were performed in 60 patients and procedure‐related bleedings occurred in 7 (11.7%) patients. Additionally, 38 (28.6%) patients experienced spontaneous (15 minor, 23 major) bleedings during a median follow‐up of 10.5 (IQR: 4.0‐27.8) months. Spontaneous bleedings in ACLD patients were more common in CPS‐B/C (at 12 months: 36.9% vs CPS‐A: 15.9%, subdistribution hazard ratio [SHR]: 3.23 [95% CI: 1.59‐6.58], P < .001), as were major bleedings (at 12 months: 22.0% vs 5.0%, SHR: 5.82 [95% CI: 2.00‐16.90], P < .001). Importantly, CPS (adjusted SHR: 4.12 [91% CI: 1.82‐9.37], P < .001), but not the presence of hepatocellular carcinoma or varices, was independently associated with major bleeding during DOAC treatment. Additionally, ACLD patients experiencing bleeding had worse overall survival (at 12 months: 88.9% vs 95.0% without bleeding; P < .001). Edoxaban anti‐Xa peak levels were higher in patients with CPS‐B/C (345 [95% CI: 169‐395] vs CPS‐A: 137 [95% CI: 96‐248] ng/mL, P = .048) and were associated with lower TM‐TGA. Importantly, spontaneous bleeding rates were comparable to VKA/LMWH patients. CONCLUSIONS: Anticoagulants including DOACs should be used with caution in patients with advanced liver disease due to a significant rate of spontaneous bleeding events
Peroxide Antimalarial Drugs Target Redox Homeostasis in Plasmodium Falciparum Infected Red Blood Cells
Plasmodium falciparum causes the most lethal form of malaria. Peroxide antimalarials based on artemisinin underpin the frontline treatments for malaria, but artemisinin resistance is rapidly spreading. Synthetic peroxide antimalarials, known as ozonides, are in clinical development and offer a potential alternative. Here, we used chemoproteomics to investigate the protein alkylation targets of artemisinin and ozonide probes, including an analogue of the ozonide clinical candidate, artefenomel. We greatly expanded the list of proteins alkylated by peroxide antimalarials and identified significant enrichment of redox-related proteins for both artemisinins and ozonides. Disrupted redox homeostasis was confirmed by dynamic live imaging of the glutathione redox potential using a genetically encoded redox-sensitive fluorescence-based biosensor. Targeted liquid chromatography-mass spectrometry (LC-MS)-based thiol metabolomics also confirmed changes in cellular thiol levels. This work shows that peroxide antimalarials disproportionately alkylate proteins involved in redox homeostasis and that disrupted redox processes are involved in the mechanism of action of these important antimalarials
A fully automated high-throughput workflow for 3D-based chemical screening in human midbrain organoids
Three-dimensional (3D) culture systems have fueled hopes to bring about the next generation of more physiologically relevant high-throughput screens (HTS). However, current protocols yield either complex but highly heterogeneous aggregates ('organoids') or 3D structures with less physiological relevance ('spheroids'). Here, we present a scalable, HTS-compatible workflow for the automated generation, maintenance, and optical analysis of human midbrain organoids in standard 96-well-plates. The resulting organoids possess a highly homogeneous morphology, size, global gene expression, cellular composition, and structure. They present significant features of the human midbrain and display spontaneous aggregate-wide synchronized neural activity. By automating the entire workflow from generation to analysis, we enhance the intra- and inter-batch reproducibility as demonstrated via RNA sequencing and quantitative whole mount high-content imaging. This allows assessing drug effects at the single-cell level within a complex 3D cell environment in a fully automated HTS workflow
PD-L1 Expression and Immune Cell Infiltration in Gastroenteropancreatic (GEP) and Non-GEP Neuroendocrine Neoplasms With High Proliferative Activity
The potential of neuroendocrine neoplasms (NEN) to respond to checkpoint inhibitors is largely unknown and full of great expectations. Immunohistochemical (IHC) studies of programmed cell death ligand 1 (PD-L1) expression in the tumor microenvironment and its implications in predicting the response to checkpoint inhibition is a very active subject. Currently, the combined analysis of PD-L1 expression and tumor-associated immune cell (TAIC) infiltration is considered the best predictive marker of therapeutic response. Here we investigated the expression of PD-L1 on tumor cells (TC) and tumor-infiltrating immune cells (IC) by IHC in 68 NEN samples with a high proliferation rate (Ki-67 >20%) from 57 patients and in 22 samples we correlated it with TAIC density by assessing intratumoral infiltration of CD3+, CD8+, and CD68+ cells. Furthermore, the tumor microenvironment was evaluated according to the classification of Teng et al. We detected PD-L1 expression in 31.6% of NEN G3. Its expression usually was weak and more IC than TC expressed PD-L1. The proportion of tumors positive for PD-L1 was comparable in NEN from different sites of origin but varied depending on tumor differentiation and disease extension. No positive IHC staining was found in 3 well-differentiated neuroendocrine tumors (NETs) with a proliferation rate above 20% (NET G3). When analyzing TAIC, we rarely (18.2%) detected intratumoral CD8+ cells, whereas infiltration by CD3+ and CD68+ cells was more common (45.5 and 59.1%, respectively). By combining CD3+ cells and PD-L1 status, we identified the immune ignorant phenotype of tumor microenvironment as being the most common phenotype, supporting the concept of a preferably combined immunotherapeutic approach in neuroendocrine carcinoma (NEC)
Mucus detachment by host metalloprotease meprin \beta requires shedding of its inactive pro-form, which is abrogated by the pathogenic protease RgpB
The host metalloprotease meprin β is required for mucin 2 (MUC2) cleavage, which drives intestinal mucus detachment and prevents bacterial overgrowth. To gain access to the cleavage site in MUC2, meprin β must be proteolytically shed from epithelial cells. Hence, regulation of meprin β shedding and activation is important for physiological and pathophysiological conditions. Here, we demonstrate that meprin β activation and shedding are mutually exclusive events. Employing ex vivo small intestinal organoid and cell culture experiments, we found that ADAM-mediated shedding is restricted to the inactive pro-form of meprin β and is completely inhibited upon its conversion to the active form at the cell surface. This strict regulation of meprin β activity can be overridden by pathogens, as demonstrated for the bacterial protease Arg-gingipain (RgpB). This secreted cysteine protease potently converts membrane-bound meprin β into its active form, impairing meprin β shedding and its function as a mucus-detaching protease
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