Fact Of Change Research Articles

MiR-143-3p modulates depressive-like behaviors via Lasp1 in the mouse ventral hippocampus

Depression is a prevalent and intricate mental disorder. The involvement of small RNA molecules, such as microRNAs in the pathogenesis and neuronal mechanisms underlying the depression have been documented. Previous studies have demonstrated the involvement of microRNA-143-3p (miR-143-3p) in the process of fear memory and pathogenesis of ischemia; however, the relationship between miR-143-3p and depression remains poorly understood. Here we utilized two kinds of mouse models to investigate the role of miR-143-3p in the pathogenesis of depression. Our findings reveal that the expression of miR-143-3p is upregulated in the ventral hippocampus (VH) of mice subjected to chronic restraint stress (CRS) or acute Lipopolysaccharide (LPS) treatment. Inhibiting the expression of miR-143-3p in the VH effectively alleviates depressive-like behaviors in CRS and LPS-treated mice. Furthermore, we identify Lasp1 as one of the downstream target genes regulated by miR-143-3p. The miR-143-3p/Lasp1 axis primarily affects the occurrence of depressive-like behaviors in mice by modulating synapse numbers in the VH. Finally, miR-143-3p/Lasp1-induced F-actin change is responsible for the synaptic number variations in the VH. In conclusion, this study enhances our understanding of microRNA-mediated depression pathogenesis and provides novel prospects for developing therapeutic approaches for this intractable mood disorder.

Critical role of thrombospondin-1 in promoting intestinal mucosal wound repair.

Thrombospondin-1 (TSP1) is a matricellular protein associated with the regulation of cell migration through direct binding interactions with integrin proteins and by associating with other receptors known to regulate integrin function, including CD47 and CD36. We previously demonstrated that deletion of an epithelial TSP1 receptor, CD47, attenuates epithelial wound repair following intestinal mucosal injury. However, the mechanisms by which TSP1 contributes to intestinal mucosal repair remain poorly understood. Our results show upregulated TSP1 expression in colonic mucosal wounds and impaired intestinal mucosal wound healing in vivo upon intestinal epithelium-specific loss of TSP1 (VillinCre/+ Thbs1fl/fl or Thbs1ΔIEC mice). We report that exposure to exogenous TSP1 enhanced migration of intestinal epithelial cells in a CD47- and TGF-β1-dependent manner and that deficiency of TSP1 in primary murine colonic epithelial cells resulted in impaired wound healing. Mechanistically, TSP1 modulated epithelial actin cytoskeletal dynamics through suppression of RhoA activity, activation of Rho family small GTPase (Rac1), and changes in filamentous-actin bundling. Overall, TSP1 was found to regulate intestinal mucosal wound healing via CD47 and TGF-β1, coordinate integrin-containing cell-matrix adhesion dynamics, and remodel the actin cytoskeleton in migrating epithelial cells to enhance cell motility and promote wound repair.

Fraping: A computational tool for detecting slight differences in fluorescence recovery after photobleaching (FRAP) data for actin polymerization analysis.

Fluorescence recovery after photobleaching (FRAP) is a laser method of light microscopy to evaluate the rapid movement of fluorescent molecules. To have a more reliable approach to analyze data from FRAP, we designed Fraping, a free access R library to data analysis obtained from FRAP. Unlike other programs, Fraping has a new form of analyzing curves of FRAP using statistical analysis based on the average curve difference. To evaluate our library, we analyzed the differences of actin polymerization in real time between dendrites and secondary neurites of cultured neuron transfected with LifeAct to track F-actin changes of neurites. We found that Fraping provided greater sensitivity than the conventional model using mobile fraction analysis. Likewise, this approach allowed us to normalize the fluorescence to the size area of interest and adjust data curves choosing the best parametric model. In addition, this library was supplemented with data simulation to have a more significant enrichment for the analysis behavior. We concluded that Fraping is a method that reduces bias when analyzing two data groups as compared with the conventional methods. This method also allows the users to choose a more suitable analysis approach according to their requirements. RESEARCH HIGHLIGHTS: Fraping is a new programming tool to analyze FRAP data to normalize fluorescence recovery curves. The conventional method uses one-point analysis, and the new one compares all the points to define the similarity of the fluorescence recovery.

Trametenolic acid inhibits migration and invasion of hepatocellular carcinoma HepG2.2.15 cells via RhoC/ROCK1 pathway

This study investigated the effect of trametenolic acid(TA) on the migration and invasion of human hepatocellular carcinoma HepG2.2.15 cells by using Ras homolog gene family member C(RhoC) as the target and probed into the mechanism, aiming to provide a basis for the utilization of TA. The methyl thiazolyl tetrazolium(MTT) assay was employed to examine the proliferation of HepG2.2.15 cells exposed to TA, and scratch and Transwell assays to examine the cell migration and invasion. The pull down assay was employed to determine the impact of TA on RhoC GTPase activity. Western blot was employed to measure the effect of TA on the transport of RhoC from cytoplasm to cell membrane and the expression of RhoC/Rho-associated kinase 1(ROCK1)/myosin light chain(MLC)/matrix metalloprotease 2(MMP2)/MMP9 pathway-related proteins. RhoC was over-expressed by transient transfection of pcDNA3.1-RhoC. The changes of F-actin in the cytoskeleton were detected by Laser confocal microscopy. In addition, the changes of cell migration and invasion, expression of proteins in the RhoC/ROCK1/MLC/MMP2/MMP9 pathway, and RhoC GTPase activity were detected. The subcutaneously transplanted tumor model of BALB/c nude mice and the low-, medium-, and high-dose(40, 80, and 120 mg·kg~(-1), respectively) TA groups were established and sorafenib(20 mg·kg~(-1)) was used as the positive control. The tumor volume and weight in each group were measured, and the expression of related proteins in the tumor tissue was determined by Western blot. The results showed that TA inhibited the proliferation of HepG2.2.15 cells in a concentration-dependent manner, with the IC_(50) of 66.65 and 23.09 μmol·L~(-1) at the time points of 24 and 48 h, respectively. The drug administration groups had small tumors with low mass. The tumor inhibition rates of sorafenib and low-, medium-and high-dose TA were 62.23%, 26.48%, 55.45%, and 62.36%, respectively. TA reduced migrating and invading cells and inhibited RhoC protein expression and RhoC GTPase activity in a concentration-dependent manner, dramatically reducing RhoC and membrane-bound RhoC GTPase. The expression of ROCK1, MLC, p-MLC, MMP2, and MMP9 downstream of RhoC can be significantly inhibited by TA, as confirmed in both in vitro and in vivo experiments. After HepG2.2.15 cells were transfected with pcDNA3.1-RhoC to overexpress RhoC, TA down-regulated the protein levels of RhoC, ROCK1, MLC, p-MLC, MMP2, and MMP9 and decreased the activity of RhoC GTPase, with the inhibition level comparable to that before overexpression. In summary, TA can inhibit the migration and invasion of HepG2.2.15 cells. It can inhibit the RhoC/ROCK1/MLC/MMP2/MMP9 signaling pathway by suppressing RhoC GTPase activity and down-regulating RhoC expression. This study provides a new idea for the development of autophagy modulators targeting HSP90α to block the proliferation and inhibit the invasion and migration of hepatocellular carcinoma cells via multiple targets of active components in traditional Chinese medicines.

Application of Raman spectroscopy to the evaluation of F-actin changes in sea urchin eggs at fertilization.

The actin filaments on the surface of echinoderm oocytes and eggs readily undergo massive reorganization during meiotic maturation and fertilization. In sea urchin eggs, the actin cytoskeletal response to the fertilizing sperm is fast enough to accompany Ca2+ signals and to guide sperm's entry into the egg. Although recent work using live cell imaging technology confirmed changes in the actin polymerization status in fertilized eggs, as was previously shown using light and electron microscopy, it failed to provide experimental evidence of F-actin depolymerization a few seconds after insemination, which is concurrent with the sperm-induced Ca2+ release. In the present study, we applied Raman microspectroscopy to tackle this issue by examining the spectral profiles of the egg's subplasmalemmal regions before and after treating the eggs with actin drugs or fertilizing sperm. At both early (15 s) and late (15 min) time points after fertilization, specific peak shifts in the Raman spectra revealed change in the actin structure, and Raman imaging detected the cytoskeletal changes corresponding to the F-actin reorganization visualized with LifeAct-GFP in confocal microscopy. Our observation suggests that the application of Raman spectroscopy, which does not require microinjection of fluorescent probes and exogenous gene expression, may serve as an alternative or even advantageous method in disclosing rapid subtle changes in the subplasmalemmal actin cytoskeleton that are difficult to resolve.

Confocal Microscopy Studies of F-Actin Cytoskeleton Distribution and Dynamics Using Fluorescent LifeAct Constructs in Bovine Adrenal Chromaffin Cells.

Cultured bovine chromaffin cells have been characterized as a successful model to study changes in the cytoskeleton during the secretory process. In this sense, the distribution and dynamics of the F-actin cytoskeleton can be studied by confocal microscopy using appropriate molecular tools such as LifeAct, a peptide that stains the structures of F-actin. In this work, we describe some methodological protocols making possible to study, under controlled stimulus conditions, the local dynamic changes of F-actin in the cortical zone and also to detect the simultaneous displacements of chromaffin granules and organelles in active zones.

Factual Changes in Inflation and National Income: Their Impact on the Tax Burden Within OECD Countries

Factual Changes in Inflation and National Income: Their Impact on the Tax Burden Within OECD Countries

State defense strategy through defense public policy analysis in the face of revolution in military affairs

State defense is a very important field to be realized to be strong, but there are many obstacles to achieving the desired defense goals. Based on the various obstacles, the priority is the provision of quality human resources. Public policy in the field of government regarding the management of civil and military human resources is equally important in realizing human resources that can produce defense technology that has a deterrent effect. This study aims to analyze the national defense system through the analysis of public defense policies in the face of a Revolution in the Military Affairs (RMA). The research method used is a qualitative approach. Data was collected through Focus Group Discussion (FGD), in-depth interviews and literature review. The characteristics of the informants in this study were 12 students of the year 2020 Marine Defense Strategy study program who had taken state defense strategy courses at the Defense University. The student is a member of the Indonesian Navy (TNI). The results of this study indicate that to realize reliable human resources without losing their identity requires an understanding of defense public policy. Changes in defense technology are also related to the RMA which continues to move forward and affects the interaction of international relations. In addition, in the face of change, the role of education is needed as a tool to keep up with actual and factual changes

Doxycycline Hydrochloride Regulates Cytoskeletal Rearrangement and Epithelial-To-Mesenchymal Transition in Malignant Rhabdoid Tumour of the Kidney.

As a highly malignant tumour, malignant rhabdoid tumours of the kidney (MRTK) are prone to metastasis and invasion, while tumour metastasis and invasion are inseparable from matrix metalloproteinases (MMPs) and epithelial-mesenchymal transformation (EMT). Moreover, the key to EMT is remodelling of the cytoskeleton. Therefore, our study is aimed at investigating whether doxycycline hydrochloride (DCH), an inhibitor of MMPs, could reverse EMT in MRTK to exert an antitumour effect by regulating MMPs and the cytoskeleton. The existence of EMT in MRTK cells was verified by bioinformatics analysis, immunofluorescence, and western blotting (WB). In vitro, the proliferation, migration, and invasion abilities of G401 cells were examined by Cell Counting Kit-8 (CCK-8), scratch, and Transwell assays, respectively. The effect of DCH on tumour growth in tumour-bearing mice was explored in in vivo experiments, and the expression of MMP2 and MMP9 and EMT correlation indexes was measured by immunofluorescence and WB, and the changes in cytoskeletal F-actin and β-tubulin were measured by fluorescence. The altered extracellular matrix (ECM) composition, EMT, and high expression of MMP2 and MMP9 existed in MRTK. DCH inhibited the proliferation, migration, and invasion of G401 cells in vitro. In vivo, DCH inhibited tumour growth in mice, downregulated the expression of MMP2 and MMP9, and partially reversed EMT. Alternatively, DCH resulted in cytoskeletal rearrangements of G401 cells. DCH, as an MMP inhibitor, is used for the first time in MRTK research, showing good antitumour effects by reversing EMT and potentially providing new therapeutic measures for MRTK treatment.

미국연방대법원의 돕스 판결에 나타난 헌법해석 논쟁

In Dobbs Case, the U.S. Supreme Court(hereinafter “the Court”) ruled that abortion was not a fundamental right guaranteed by the Constitution. The Dobbs Case contains debates on fundamental and important issues raised in constitutional interpretation. Interpreting the “liberty” of Due Prcess Clause, the Court emphasized the text and history at the time of enactment of the 14th Amendment. That approach is similar to so-called originalist interpretation. On the other hand, the dissenting opinion argues that the Constitution has steadily developed through important constitutional principles, American history and tradition, and the gradual evolution of the Court’s precedents. Several crticisms of originalism are equivalent to the Court’s opinion. The Court overruled Roe and Casey on the ground that the Roe was egregiously wrong from the start, while the dissenting opinion stated that the Court violates the principle of stare decisis and the rule of law for overruling Roe even though there has been no legal or factual change except for the change in the composition of the Court. Though the fact that Roe has been consistently challenged over the past 50 years shows that Roe is not so-called super precedent, it also shows that Roe has been repeatedly confirmed as a good precedent. Overruling Roe means abolishing a fundamental right that has been recognized so far, not recognizing a new fundamental right or expanding the scope of a existing fundamental right. In this regards, the Court should have provided a stronger justification for overruling Roe. The Court held that it had no authority to determine the issue of abortion because the Constitution is neutral on abortion, and that the resolution of this issue should be left to the people and their elected representatives. The Court is relying on merely a majority-ruled democracy, and it is inconsistent with another important concept of democracy, constitutional democracy that requires constitutional protection of the minority from the tyranny of the majority.

Structural basis for tunable control of actin dynamics by myosin-15 in mechanosensory stereocilia.

The motor protein myosin-15 is necessary for the development and maintenance of mechanosensory stereocilia, and mutations in myosin-15 cause hereditary deafness. In addition to transporting actin regulatory machinery to stereocilia tips, myosin-15 directly nucleates actin filament (“F-actin”) assembly, which is disrupted by a progressive hearing loss mutation (p.D1647G, “jordan”). Here, we present cryo–electron microscopy structures of myosin-15 bound to F-actin, providing a framework for interpreting the impacts of deafness mutations on motor activity and actin nucleation. Rigor myosin-15 evokes conformational changes in F-actin yet maintains flexibility in actin’s D-loop, which mediates inter-subunit contacts, while the jordan mutant locks the D-loop in a single conformation. Adenosine diphosphate–bound myosin-15 also locks the D-loop, which correspondingly blunts actin-polymerization stimulation. We propose myosin-15 enhances polymerization by bridging actin protomers, regulating nucleation efficiency by modulating actin’s structural plasticity in a myosin nucleotide state–dependent manner. This tunable regulation of actin polymerization could be harnessed to precisely control stereocilium height.

Trabecular Meshwork Cholesterol Levels Regulate Actin Polymerization and Tunneling Nanotubes

Trabecular meshwork (TM) tissue is made of highly contractile mechanosensitive cells regulating aqueous humor (AH) outflow facility and intraocular pressure (IOP). Increased actin‐mediated contraction of TM elevates IOP causing glaucoma and irreversible blindness. This study aims at understanding the role of cholesterol in regulating actin dynamics in human TM (HTM) cells. To test this, HTM cells were treated with SiR‐Actin in serum‐free media overnight and F‐actin changes were recorded using live‐cell time‐lapse (5 min interval) confocal imaging before and during exposure to ‐ A) 10mM methyl‐β‐cyclodextrin (MβCD) for 1h for acute removal of cellular cholesterol, B) 100μM cholesterol‐saturated MβCD (MβCD‐CHOL) for 1h to enrich cholesterol, and C) 10mM MβCD for 1h followed by cholesterol supplementation using MβCD‐CHOL for 1h. F‐actin fluorescence intensity changes were calculated and unpaired t‐test was used for statistical analyses and results were significant if p<0.05 with a sample size of n= 4‐57. HTM cells plated on coverslips were treated as A – C as mentioned above, cholesterol and lipid synthesis inhibitors for 24h ‐ D) 100μM atorvastatin and E) 20μM fatostatin, respectively, F) actin polymerization disruptor ‐ 10μM cytochalasin D (CYTD) for 1h, G) 10μM CYTD for 1h followed by 100μM MβCD‐CHOL for 1h, H) microtubule disruptor ‐ 1μM demecolcine (DEM) for 1h, I) 1μM DEM for 1h followed by 100μM MβCD‐CHOL for 1h. Cells without treatment were used as control. After all these treatments, cells were fixed and immunofluorescence (IF) was performed to check for cholesterol using filipin, F‐actin by phalloidin, focal adhesion (FA) localization based on ‐ vinculin and paxillin distribution. Further F‐actin/G‐actin in vitro assay was performed to quantify the changes in actin polymerization under the conditions A – I compared to the control. The imaging analysis showed cholesterol removal significantly decreased F‐actin fluorescence intensity from 20min sustaining up to 1h and decreased the FA distribution. Cholesterol supplementation led to partial rescue of actin and FA indicating the re‐establishment of actin cytoskeleton and increased tunneling nanotube structures enhancing the cell‐cell communication (Figure 1). Moreover, IF results show that atorvastatin and fatostatin decreased F‐actin and FA distribution. CYTD disrupted F‐actin network leaving remnant filament ends and decreased FA but cholesterol enrichment increased F‐actin branches formed at ~70‐degree angle indicating Arp2/3 activation. DEM treatment increased F‐actin and FA, and cholesterol enrichment induced thick F‐actin filaments. These results were confirmed by quantitative F/G‐actin ratio decrease and increase upon cholesterol removal and enrichment, respectively. Additionally, supplementing cholesterol after removal increased the ratio compared to solely removing cholesterol. Interestingly, F/G‐actin ratio increased under CYTD treatment indicating that CYTD disrupted longer actin filaments but helped polymerization of newly formed actin filaments. Finally, DEM treatment increased F/G‐actin ratio, which was further increased by cholesterol enrichment. This systematic evaluation of cholesterol modulation on TM actin cytoskeleton polymerization identifies the significance of maintaining membrane and cellular cholesterol levels and cellular communication for achieving IOP homeostasis.

Caveolin-1 Involves in the Rearrangement of F-actin through NF-κB Pathway in Endothelial Cells Induced by Lipopolysaccharide

Objective: To explore the role and possible mechanism of Caveolin-1 in the rearrangement of F-actin in endothelial cell induced by lipopolysaccharides (LPS).Methods: EA.hy926 cells were divided into 4 Groups: Group C (control Group), Group L (LPS 10μg/mL Group), Group S (cav-1-siRNA548 + LPS 10μg/mL Group) and Group N (cav-1-siRNA548 and L-NAME 10μM +LPS 10μg/mL Group). Real-Time PCR analysis was performed to measure the mRNA expression. Immunofluorescence staining was carried out to observe the changes of F-actin in different group.Results: We found that treatment of siRNA548 reduced the mRNA expression of caveolin-1; the mRNA expression of peNOS-s1177 in Group S significantly increased when compared with Group C and Group L, respectively. Six hours after LPS treatment, the mRNA expression of peNOS-s1177 is higher than any other time point in Group L, while the mRNA expression of peNOS-s1177 is highest after LPS treatment for 3 hours in Group S. We also found that the mRNA expression of NF-κB in Group L, S and N remarkably upregulated when compared with Group C, respectively. Moreover, the mRNA expression of NF-κB in Group L and N significantly upregulated compared with Group S. The immunofluorescence staining showed that EA.hy926 cell strain manifested F-actin depolymerization and reconstitution after LPS treatment for 6 hours, and the phenomenon had a time-dependent manner. Application of cav-1-siRNA548 could delay the depolymerization and reconstruction of F-actin, and with a lesser degree, when application of L-NAME could reverse the response.Conclusions: These data indicate that Caveolin-1 may have an important role in the modulation of LPS- induced endothelial F-actin depolymerization. And Caveolin-1 may modulate F-actin depolymerization and reconstitution through eNOS-NF-κB pathway.

URBAN HEATING SYSTEM VIRTUAL STAND UNDER DATA INCOMPLETE CONDITIONS

The problem of heat load optimal regulation in a boiler house considered to provide heat carrier to end users, taking into account the permissible temperature deviations according to the temperature schedule, is relevant for a heat supplying organization. Regulation in a boiler house that feeds a heating network with unknown thermophysical characteristics is a problem that belongs to the class of poorly formalized problems. This is due, not least, to the specific features of heating system exploitation. The problem relatively easily solved at different ambient temperatures and at different times in the data completeness case on the above specific features. Unfortunately, collecting such information is almost impossible. We have to pose and solve the problem under conditions of uncertainty. Therefore, decided to develop an urban heating system virtual stand under data incomplete conditions, which will allow creating a heating system models with various conditions of heat loss, with heat consumers of different categories and different heat energy consumption. It will allow to simulate a changes made without making factual changes in an urban heating system structure. The object of the study is a closed urban heating system with a complex topology, and the subject is calculation models of a heating system, which allow determining the temperature loss of the coolant in the sections of the heating system based on data processing from general house metering devices (GHMD). The aim of the work is to improve the efficiency of an urban heating system management based on data obtained using a virtual stand. A conceptual model developed and the main functionality of the virtual stand implemented. Based on a number of numerical experiments carried out, an algorithm formulated and implemented within the framework of a virtual stand, which makes it possible to determine total thermal resistances values at each section of the heating system from GHMD data. The stand tested on the urban heating system of the Lysva city. The deviation of the temperature values calculated within the framework of the model implemented in the virtual stand from the temperatures obtained from the GHMD did not exceed 5 %. Consequently, this virtual stand can used for more efficient urban heating system management, taking into account the calculation error.

Mechanisms of constraint: a clinical inquiry of digital infrastructuring in municipalities

PurposeThe purpose of this study is to contribute to research concerning the role of digital infrastructure in digital government. This is done by answering the research question: how does digital infrastructuring constrain ambidexterity in public sector organizations?Design/methodology/approachThe research is designed as a clinical inquiry in a large Swedish municipality, involving data collection in the form of interviews and internal documents. The method of analysis involves both exploring generative mechanisms in digital infrastructuring and theorizing on the findings based on previous literature.FindingsThe findings identify four generative mechanisms through which stability and change in digital infrastructuring constrain ambidexterity in terms of both efficiency (exploitation) and innovation (exploration).Research limitations/implicationsThis study’s limitations are related to international and intersectoral transferability and risks associated with its approach to clinical inquiry. The main implications are its contribution to the literature on how stability counteracts not only innovation but also efficiency and how change counteracts not only efficiency but also innovation.Practical implicationsThis study identifies clear generative mechanisms that should be avoided by managers striving for digital government, and it offers clear recommendations for said managers regarding how to avoid them.Social implicationsThis study offers implications for national-level digital infrastructure policy and contributes to efforts to increase the capabilities of digital government.Originality/valueAs two of the four identified generative mechanisms are novel contributions, this study offers a concrete addition to existing research. This study has resulted in factual change in the studied organization as well as at the national level through successful dissemination of the findings for both policy and practice in other public sector organizations.

Acidic microenvironment enhances MT1-MMP-mediated cancer cell motility through integrin β1/cofilin/F-actin axis.

Tumor acidic microenvironment is the main feature of many solid tumors. As a part of the tumor microenvironment, it has a profound impact on the occurrence and development of tumors. However, the research on how tumor cells sense the changes of the external microenvironment and how the intracellular subcellular structures transmit the signals from extracellular to intracellular is unclear. In this study, we identify that the acidic microenvironment enhances cancer cell motility, and the expression of membrane-anchored membrane type 1-matrix metalloproteinase is also associated with cell motility, which indicates more degradation of the ECM under the acidic microenvironment. Moreover, the expression of cofilin is low in the acidic microenvironment, and the F-actin filaments are distributed more along the cells. The cytoskeletal F-actin changes are consistent with the potential of a high-invasive phenotype. Further study reveals the upstream control of the signal transductions from extracellular to intracellular, that is, the integrin β1 functions to trigger the biological responses under the acidic microenvironment. Our results demonstrate that the acidic microenvironment enhances cancer cell motility through the integrin β1/cofilin/F-actin signal axis. This study clearly shows the scheme of the signal transmissions from extracellular to intracellular and further reveals the cytoskeletal roles for the contributions of cancer cell motility under acidic microenvironment, which provides new targets for cancer intervention from the biochemical and biophysical perspectives.

Dynamic epistemic logics for abstract argumentation

This paper introduces a multi-agent dynamic epistemic logic for abstract argumentation. Its main motivation is to build a general framework for modelling the dynamics of a debate, which entails reasoning about goals, beliefs, as well as policies of communication and information update by the participants. After locating our proposal and introducing the relevant tools from abstract argumentation, we proceed to build a three-tiered logical approach. At the first level, we use the language of propositional logic to encode states of a multi-agent debate. This language allows to specify which arguments any agent is aware of, as well as their subjective justification status. We then extend our language and semantics to that of epistemic logic, in order to model individuals’ beliefs about the state of the debate, which includes uncertainty about the information available to others. As a third step, we introduce a framework of dynamic epistemic logic and its semantics, which is essentially based on so-called event models with factual change. We provide completeness results for a number of systems and show how existing formalisms for argumentation dynamics and unquantified uncertainty can be reduced to their semantics. The resulting framework allows reasoning about subtle epistemic and argumentative updates—such as the effects of different levels of trust in a source—and more in general about the epistemic dimensions of strategic communication.

INCREASED EXPRESSION OF EPITHELIAL SODIUM CHANNEL AFFECTS MECHANICAL PROPERTIES OF ENDOTHELIAL CELLS BY REORGANISING THE F-ACTIN CYTOSKELETON

Objective: Epithelial sodium channel (ENaC) in the kidney maintain body salt/water balance and regulate blood pressure. Recent finding suggests that endothelial cells express ENaC. Here elevated ENaC contributes to increased endothelial cell stiffness (ECS) that associates with endothelial dysfunction and hypertension. dysfunction and hypertension. However, the mechanism how ENaC influence ECS remains unknown. This study aims to investigate the potential role of ENaC subunits in mediating ECS by cytoskeletal changes. I hypothesize ENaC mediated ECS via an increased expression of F-actin. To challenge our hypothesis, ENaC protein expression was quantified by Western blot in human umbilical vein endothelial cells (HUVECs) treated with aldosterone under static condition (0 dyn/cm2) and under laminar shear stress (LSS, 10 dyn/cm2, 24 h). Atomic Force Microscopy (AFM) was used to measure cell stiffness and changes of F-actin were assessed by immunofluorescence microscopy. Under static condition, aldosterone significantly increased ?-, and ?-ENaC protein levels. On the other hand, under LSS conditions aldosterone increased ?-, and ?-ENaC protein levels. Also under static condition, a significantly increased Young's modulus was determined in both fixed and live HUVEC cells treated with aldosterone. Furthermore, the increased stiffness in aldosterone treated cells revealed increased F-actin levels. Overall, these findings indicate that aldosterone has different effects on ENaC subunit expression in HUVECs grown under static and LSS conditions. The increased ENaC expression does increase ECS. This seems to involve an increased F-actin expression as a major determinant of ECS. Therefore, this study may provide a new mechanism for ENaC-mediated ECS and blood pressure regulation.

EVIDENCE HOW EPITHELIAL SODIUM CHANNEL PROMOTES STIFFNESS IN HUMAN AND MOUSE ENDOTHELIAL CELLS

Objective: The epithelial sodium channels (ENaCs) in the kidney maintain body salt/water balance and contributes to blood pressure regulation and hypertension. Recent finding suggests that ENaCs in endothelial cells are potential players mediating endothelial cell stiffness (ECS). Increased ECS is an important determinant of hypertension that coincides with altered endothelial nitric oxide (NO) production and endothelial dysfunction. Herein, we aim to uncover the molecular mechanism how ENaC influences ECS. I hypothesize that F-actin changes as a potential target through which ENaC mediates its effect. Design and method: ENaC subunit protein levels in Human Umbilical Vein Endothelial Cells (HUVECs) and Mouse Myocardial Endothelial Cells (MyEnd) cells were quantified by Western blotting. Aldosterone was used to increase ENaC expression. Changes in ECS assessed with Atomic Force Microscopy (AFM). If changes in F-actin cell cytoskeleton is correlated with ENaC expression and ECS, immunofluorescence microscopy was used and quantified. Results: Aldosterone was observed to significantly increase alpha-ENaC (both in human and mouse cells) and delta-ENaC (human specific) protein levels which were reversed by the additional incubation with amiloride (ENaC blocker). The elevated ENaC expression with aldosterone was associated with an increased Young's modulus that is indicative of elevated ECS observed in both human and mouse endothelial cells. The upregulated ENaC expression and increased stiffness was also translated into increased F-actin in response to aldosterone. Conclusions: Taken together, our study provides experimental evidence of increased ENaC protein level with increased F-actin cell cytoskeleton in endothelial cells that may promote ECS. This is a new mechanism through which ENaC mediate ECS and contributes to endothelial dysfunction and hypertension.

Fatally Flawed—Making Sense of US News & World Report Mortality Scores

This Viewpoint proposes that the variability in US News & World Report specialty ranking reflects unreliable or imprecise methods rather than factual changes in ear, nose, and throat program quality.