Secretion Of Vimentin and its influence on cellular functionality

The cytoskeleton is a dynamic network of filaments comprising actin filaments, microtubules, and intermediate filaments in the cytoplasm of cells. Vimentin is an intermediate filament protein that plays a crucial role in adhesion, migration, and signalling. These functions of vimentin have broader implications on inflammation, wound healing, cell physiology, and immune response. Inside the cell, the vimentin network extends from the nucleus to the cell's periphery. However, vimentin gets out to the extracellular environment under the circumstances such as activation, stress, and senescence. However, the influence of such vimentin on general cellular functions and its characteristics is not well established. This thesis demonstrates that extracellular addition of vimentin enhances proliferation, adhesion and migration prominently in cancer cells (MCF-7), overexpressing insulin-like growth factor 1 (IGF1-R). Interestingly, in SARS-CoV-2 infection, the extracellular vimentin preincubation with the SARS-CoV-2 receptor binding domain protected the cancer (MCF-7) cell's monolayer integrity. Further investigation on the characteristics of extracellular vimentin found secretion of vimentin from the back of activated macrophages in the form of small fragments, enhancing phagocytosis and migration of activated macrophages. Collectively, this work demonstrates new insights into vimentin secretion and its implications on cellular functionality.Das Zytoskelett ist ein dynamisches Netz von Filamenten, das aus Aktinfilamenten, Mikrotubuli und Zwischenfilamenten im Zytoplasma von Zellen besteht. Vimentin ist ein Zwischenfilamentprotein, das eine entscheidende Rolle bei Adhäsion, Migration und Signalübertragung spielt. Diese Funktionen von Vimentin haben weitreichende Auswirkungen auf Entzündungen, Wundheilung, Zellphysiologie und Immunreaktion. Innerhalb der Zelle erstreckt sich das Vimentin-Netzwerk vom Zellkern bis zur Peripherie der Zelle. Unter bestimmten Umständen wie Aktivierung, Stress und Seneszenz gelangt Vimentin jedoch auch in die extrazelluläre Umgebung. Der Einfluss dieses Vimentins auf die allgemeinen Zellfunktionen und seine Eigenschaften ist jedoch nicht gut untersucht. Diese Arbeit zeigt, dass die extrazelluläre Zugabe von Vimentin die Proliferation, Adhäsion und Migration in Krebszellen (MCF-7), die den insulinähnlichen Wachstumsfaktor 1 (IGF1-R) überexprimieren, deutlich erhöht. Interessanterweise schützte das extrazelluläre Vimentin bei einer SARS-CoV-2-Infektion vor der Inkubation mit der SARS-CoV-2- Rezeptorbindungsdomäne die Integrität der Krebszellen (MCF-7) in der Monolage. Weitere Untersuchungen zu den Eigenschaften von extrazellulärem Vimentin ergaben, dass Vimentin von der Rückseite aktivierter Makrophagen in Form kleiner Fragmente abgesondert wird, was die Phagozytose und Migration aktivierter Makrophagen fördert. Insgesamt zeigen diese Arbeiten neue Erkenntnisse über die Vimentin-Sekretion und ihre Auswirkungen auf die zelluläre Funktionalität

Maternal and perinatal outcome in heart disease complicating pregnancy

Background: Congenital as well as acquired heart diseases remain one of the important factors complicating pregnancy and remains a significant cause of maternal as well as perinatal morbidity and mortality. Pregnant women with cardiac diseases need a comprehensive management strategy to minimize the adverse effect of cardiac conditions on pregnancy and its outcome.Methods: This was an observational study conducted in a tertiary care hospital located in an urban area. Pregnant patients diagnosed to be having congenital or acquired heart diseases and admitted either in ward, labour room or intensive care unit were included in this study on the basis of a predefined inclusion and exclusion criteria. Detailed history was taken and clinical examination was done in all the cases. Patients were classified according to New York Heart Association. Maternal and perinatal Outcome was studied in cases.Results: The incidence of cardiac disease amongst pregnant patients during study period was found to be 0.58%. The mean age of studied cases was found to be 23.16±5.06 years. Most of the patients were primigravida (85.71%) and 6 patients (14.29%) were multigravida. The majority of the patients (76.19%) belonged to NYHA grade I whereas 8 (19.05%) patients belonged to NYHA class II. 1 patient belonged to NYHA Class III and Class IV respectively. Isolated mitral stenosis secondary to rheumatic valvular involvement was the single most common lesion seen in studied cases and was seen in 8 (19.05%) patients. Ventricular septal defect was most common congenital heart disease (14.28%). 26 (61.90 %) delivered by normal vaginal delivery whereas emergency and elective LSCS was done in 9 (21.43%) and 6 (14.29%) patients respectively. nature of cardiac disease was common factor for elective cesarean section which was done in 5 cases (11.90%). Postpartum cardiac failure (14.29%) and postpartum hemorrhage (9.52%) were common maternal complications. 24 (57.14%) neonates required admission in neonatal intensive care unit. The most common indication for NICU admission was found to be low birth weight (23.81%) followed by birth asphyxia (19.05%).Conclusions: Cardiac disease in pregnancy is associated with increased risk of maternal as well as perinatal morbidity and mortality. Early diagnosis and management during pregnancy is essential to reduce maternal as well as perinatal outcome in these cases

Role of Extracellular Vimentin in Cancer-Cell Functionality and Its Influence on Cell Monolayer Permeability Changes Induced by SARS-CoV-2 Receptor Binding Domain

The cytoskeletal protein vimentin is secreted under various physiological conditions. Extracellular vimentin exists primarily in two forms: attached to the outer cell surface and secreted into the extracellular space. While surface vimentin is involved in processes such as viral infections and cancer progression, secreted vimentin modulates inflammation through reduction of neutrophil infiltration, promotes bacterial elimination in activated macrophages, and supports axonal growth in astrocytes through activation of the IGF-1 receptor. This receptor is overexpressed in cancer cells, and its activation pathway has significant roles in general cellular functions. In this study, we investigated the functional role of extracellular vimentin in non-tumorigenic (MCF-10a) and cancer (MCF-7) cells through the evaluation of its effects on cell migration, proliferation, adhesion, and monolayer permeability. Upon treatment with extracellular recombinant vimentin, MCF-7 cells showed increased migration, proliferation, and adhesion, compared to MCF-10a cells. Further, MCF-7 monolayers showed reduced permeability, compared to MCF-10a monolayers. It has been shown that the receptor binding domain of SARS-CoV-2 spike protein can alter blood–brain barrier integrity. Surface vimentin also acts as a co-receptor between the SARS-CoV-2 spike protein and the cell-surface angiotensin-converting enzyme 2 receptor. Therefore, we also investigated the permeability of MCF-10a and MCF-7 monolayers upon treatment with extracellular recombinant vimentin, and its modulation of the SARS-CoV-2 receptor binding domain. These findings show that binding of extracellular recombinant vimentin to the cell surface enhances the permeability of both MCF-10a and MCF-7 monolayers. However, with SARS-CoV-2 receptor binding domain addition, this effect is lost with MCF-7 monolayers, as the extracellular vimentin binds directly to the viral domain. This defines an influence of extracellular vimentin in SARS-CoV-2 infections

Bioactive coating with low-fouling polymers for the development of biocompatible vascular implants

The replacement of occluded blood vessels and endovascular aneurysm repair (EVAR) are performed with the use of synthetic vascular grafts and stent grafts, respectively. Both implants lead to frequent clinical complications that are different but due to a similar problem, namely the inadequate surface properties of the polymeric biomaterials used (generally polyethylene terephthalate (PET) or expanded polytetrafluoroethylene (ePTFE)). Therefore the general objective of this thesis was to create a versatile bioactive coating on vascular biomaterials that reduce material-induced thrombosis and promote desired cell interactions favorable to tissue healing around implants. The use of low-fouling backgrounds was decided in order to reduce platelet adhesion as well as the non-specific protein adsorption and thus increase the bioactivity of immobilized biomolecules. As part of the preliminary objective, a multi-arm polyethylene glycol (PEG) was chosen to create a versatile low-fouling surface, since the current coating methods are far from being versatile and rely on the availability of compatible functional groups on both PEG and the host surface. This PEG coating method was developed by taking advantage of novel primary amine-rich plasma polymerized coatings (LP). As demonstrated by quartz crystal microbalance with dissipation (QCM-D), fluorescence measurements and platelet adhesion assays, our PEG coatings exhibited low protein adsorption and almost no platelet adhesion after 15 min perfusion in whole blood. Although protein adsorption was not completely abrogated and short-term platelet adhesion assay was clearly insufficient to draw conclusions for long-term prevention of thrombosis in vivo, the low-fouling properties of this PEG coating were sufficient to be exploited for further coupling of bioactive molecules to create bioactive coatings. Therefore, as a part of the second objective, an innovative and versatile bioactive coating was developed on PEG and carboxymethylated dextran (CMD), using the combination of an adhesive peptide (KQAGDV/RGD) and epidermal growth factor (EGF). CMD was chosen as an alternative to PEG due to its better low-fouling properties and the presence of abundant carboxyl terminal groups. Although the QCM-D technique enabled us to optimize the combined immobilization of KQAGDV/RGD and EGF, cell adhesion assay results did not show improvement of vascular smooth muscle cell (VSMC) adhesion on peptide-modified PEG or CMD surfaces. Among the reasons explaining low cell adhesion on peptides grafted low-fouling surfaces is the difficulty of preventing protein adsorption/platelet adhesion without significantly reducing cell adhesion. Preliminary data in our laboratory indicated that CS could be an ideal substrate to find this compromise. For that reason, the final objective of this PhD consisted in evaluating the potential of chondroitin sulfate (CS) coating by comparing its properties with well-known low-fouling polymers such as PEG and CMD. It was shown that CS presents selective low-fouling properties, low-platelet adhesion and pro-endothelial cell (EC) adhesive properties As demonstrated by QCM-D and fluorescence measurements, CS was as effective as PEG in reducing fibrinogen adsorption, but it reduced adsorption of bovine serum albumin (BSA) and fetal bovine serum (FBS) to a lower extent than PEG and CMD surfaces. Whole blood perfusion assays indicated that all three surfaces drastically decreased platelet adhesion and activation to levels significantly lower than PET surfaces. However, while EC adhesion and growth were found to be very limited on PEG and CMD, cell attachment on CS was strong, with focal adhesion points and resistance to shear stress. CS coatings therefore form a low-thrombogenic background promoting the formation of a confluent endothelium layer, which may then act as an active anti-thrombogenic surface. CS coating can also be used to further graft biomolecules. Combination of LP, CS coating followed by GF immobilization shows great promise as a bioactive coating to optimize the biocompatibility and clinical outcome of vascular implants, in particular vascular grafts

A RELIABLE DATA OUTSOURCING WITH REVOCABLE REPOSITORY IDENTITY-BASED CONVERSION IN CLOUD COMPUTING

In the cloud of public places, this document focuses on downloading proxy-based data and verifying the integrity of remote data. By using the public cloud platform, customers are freed from the burden of storage management and general access to data with independent geographic locations, and so on. This research is based on the results of the study of proxy coding and encryption of the public key based on the identity and authentication of remote data security in the public cloud. When using public-key cryptography based on identity, the proposed ID-PUIC protocol is effective because the administration of certificates is eliminated. ID-PUIC is a verification of remote data integrity of proxy load and proxy data driven by proxy in the cloud of public places. Throughout the analysis, the administrator will be restricted to connecting to the network in order to protect against collusion. However, the proposed ID-PUIC protocol can also achieve remote verification of data integrity, authorization of remote verification of data integrity and verification of the integrity of remote data in general in accordance with the original authorization of the client. However, the legal work of the Director will continue throughout the analysis process. We provide the official system model and the security model for the ID-PUIC protocol. Then, in line with bilateral couples, we designed the first concrete protocol ID-PUIC. Within the random Oracle model, our secure ID-PUIC protocol is secure

AN APPROACH TO RE-ORDERING THE IMAGES BASED ON VARIOUS DOMAINS

A single destination function is proposed to improve the codebook within a P2P atmosphere, which shows both the convenience information and the synchronization of the workload synchronously. Therefore, we recommend using the code line update method to improve the information exchanged between ID information and related information, as well as balancing the workload between the nodes that manage different coded words. It is proposed that the code update formula be distributed according to the code words, which improves the functionality of the objective at a low update cost. While most of the current methods focus on the indexing of high-dimensional visual characteristics and also on scalability limitations, we recommend in this document scalable ways to retrieve content-based images in point-to-point systems using a word bag. The codebook should be updated as the atmosphere periodically, instead of static storage. In this document, we offer a unique approach to dynamically generate a blade notebook around the world, which shows discrimination and workload balance. In addition, a peer-to-peer network is being developed dynamically, which makes the difficult codebook less efficient for recovery tasks. In order to further improve the recovery performance and reduce the cost of the network, the development of the cataloging of pruning techniques. Unlike central environments, the important challenge would be to have an efficient global codebook, where the images are distributed throughout the peer network

Concussion-related Alterations in Neural Activity During Emotion Recognition: Case Studies of Short-term and Residual Effects

Concussions have recently become an area of concern among the general public, but a clear understanding of their total consequence is still being developed. Symptoms of concussions are wide-ranging, encapsulating a plethora of cognitive and emotional abilities that could be affected. Concussions transiently disrupt neural activation as well as behavioral responses across multiple categories. Skills pertaining to various aspects of emotions are often affected yet have rarely been studied after concussions. We present two case studies of collegiate athletes with a history of multiple concussions. This paper highlights the case of a collegiate athlete who had obtained two previous concussions with the most recent being sustained sixteen days prior to neuroimaging. A second athlete with two lifetime concussions was tested one year after the most recent injury. The current study utilized a novel emotional recognition task to assess the behavioral and neural effects of this injury. A group of five controls responded with high accuracy rates and quick response times to the task. They showed activation in regions of the frontal lobe as well as facial recognition areas of the occipital lobe. The 16-day case subject was impaired in recognizing emotions relative to controls and showed little to no overlap in brain activity for regions involved in emotional face processing. The athlete with a longer post-concussion period also showed residual effects of neural activity alteration when compared to controls with few overlapping active regions. Specific brain regions were activated in this group but not in controls including the sensorimotor cortex, supramarginal gyrus, and lateral occipital cortex. By taking a more individual approach in examination of neural activity post-concussion, we may be able to gain a better understanding of this heterogeneous injury

A novel universal algorithm for filament network tracing and cytoskeleton analysis

The rapid development of advanced microscopy techniques over recent decades has significantly increased the quality of imaging and our understanding of subcellular structures, such as the organization of the filaments of the cytoskeleton using fluorescence and electron microscopy. However, these recent improvements in imaging techniques have not been matched by similar development of techniques for computational analysis of the images of filament networks that can now be obtained. Hence, for a wide range of applications, reliable computational analysis of such two-dimensional methods remains challenging. Here, we present a new algorithm for tracing of filament networks. This software can extract many important parameters from grayscale images of filament networks, including the mesh hole size, and filament length and connectivity (also known as Coordination Number). In addition, the method allows sub-networks to be distinguished in two-dimensional images using intensity thresholding. We show that the algorithm can be used to analyze images of cytoskeleton networks obtained using different advanced microscopy methods. We have thus developed a new improved method for computational analysis of two-dimensional images of filamentous networks that has wide applications for existing imaging techniques. The algorithm is available as open-source software