IMPACT OF COVID-19 ON MULTIPLE BODY ORGAN FAILURE: A REVIEW

COVID-19 is a highly contagious disease caused by Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2); which is a novel single-stranded positive RNA infection which consist of cytokines that activate the pathogenic systems that cause high respiratory pain condition, and adversely affect on multiple body organ in humans as per their immunity standards to fight against the virus. SARS-CoV-2 enters the host cell through Angiotensin-Converting Enzyme 2 (ACE 2). ACE 2 is a sub-part of the Renin-Aldosterone Angiotensin System (RAAS), intelligently communicated in the body's kidney, heart, lungs, and malignant tissues. The malfunctioning of RAAS in the body leads to hypertension, cardiovascular sicknesses, endocrine system and negatively affects a brain-body communication channel. Treatments on the RAAS structure, 'thiazolidinedione's and smoking, toxemia, kidney, lungs disorder due to the SARS-CoV-2 attack on the host cell and notice the behavioral changes of body organs the arrival of cytokines that causes multi-organ damage. This paper involves the study of the effects of coronavirus disease on multiple body-organ injuries

Role of RNA interference (RNAi) in dengue virus replication and identification of NS4B as an RNAi suppressor

RNA interference (RNAi) is an important antiviral defense response in plants and invertebrates; however, evidences for its contribution to mammalian antiviral defense are few. In the present study, we demonstrate the anti-dengue virus role of RNAi in mammalian cells. Dengue virus infection of Huh 7 cells decreased the mRNA levels of host RNAi factors, namely, Dicer, Drosha, Ago1, and Ago2, and in corollary, silencing of these genes in virus-infected cells enhanced dengue virus replication. In addition, we observed downregulation of many known human microRNAs (miRNAs) in response to viral infection. Using reversion-of-silencing assays, we further showed that NS4B of all four dengue virus serotypes is a potent RNAi suppressor. We generated a series of deletion mutants and demonstrated that NS4B mediates RNAi suppression via its middle and C-terminal domains, namely, transmembrane domain 3 (TMD3) and TMD5. Importantly, the NS4B N-terminal region, including the signal sequence 2K, which has been implicated in interferon (IFN)-antagonistic properties, was not involved in mediating RNAi suppressor activity. Site-directed mutagenesis of conserved residues revealed that a Phe-to-Ala (F112A) mutation in the TMD3 region resulted in a significant reduction of the RNAi suppression activity. The green fluorescent protein (GFP)-small interfering RNA (siRNA) biogenesis of the GFP-silenced line was considerably reduced by wild-type NS4B, while the F112A mutant abrogated this reduction. These results were further confirmed by in vitro dicer assays. Together, our results suggest the involvement of miRNA/RNAi pathways in dengue virus establishment and that dengue virus NS4B protein plays an important role in the modulation of the host RNAi/miRNA pathway to favor dengue virus replication

A DSMC-CFD coupling method using surrogate modelling for low-speed rarefied gas flows

A new Micro-Macro-Surrogate (MMS) hybrid method is presented that couples the Direct Simulation Monte Carlo (DSMC) method with Computational Fluid Dynamics (CFD) to simulate low-speed rarefied gas flows. The proposed MMS method incorporates surrogate modelling instead of direct coupling of DSMC data with the CFD, addressing the limitations CFD has in accurately modelling rarefied gas flows, the computational cost of DSMC for low-speed and multiscale flows, as well as the pitfalls of noise in conventional direct coupling approaches. The surrogate models, trained on the DSMC data using Bayesian inference, provide noise-free and accurate corrections to the CFD simulation enabling it to capture the non-continuum physics. The MMS hybrid approach is validated by simulating low-speed, steady-state, force-driven rarefied gas flows in a canonical 1D parallel-plate system, where corrections to the boundary conditions and stress tensor are considered and shows excellent agreement with DSMC benchmark results. A comparison with the typical domain decomposition DSMC-CFD hybrid method is also presented, to demonstrate the advantages of noise-avoidance in the proposed approach. The method also inherently captures the uncertainty arising from micro-model fluctuations, allowing for the quantification of noise-related uncertainty in the predictions. The proposed MMS method demonstrates the potential to enable multiscale simulations where CFD is inaccurate and DSMC is prohibitively expensive

The Transcription Factor YY1 Is a Substrate for Polo-Like Kinase 1 at the G2/M Transition of the Cell Cycle

Yin-Yang 1 (YY1) is an essential multifunctional zinc-finger protein. It has been shown over the past two decades to be a critical regulator of a vast array of biological processes, including development, cell proliferation and differentiation, DNA repair, and apoptosis. YY1 exerts its functions primarily as a transcription factor that can activate or repress gene expression, dependent on its spatial and temporal context. YY1 regulates a large number of genes involved in cell cycle transitions, many of which are oncogenes and tumor-suppressor genes. YY1 itself has been classified as an oncogene and was found to be upregulated in many cancer types. Unfortunately, our knowledge of what regulates YY1 is very minimal. Although YY1 has been shown to be a phosphoprotein, no kinase has ever been identified for the phosphorylation of YY1. Polo-like kinase 1 (Plk1) has emerged in the past few years as a major cell cycle regulator, particularly for cell division. Plk1 has been shown to play important roles in the G/M transition into mitosis and for the proper execution of cytokinesis, processes that YY1 has been shown to regulate also. Here, we present evidence that Plk1 directly phosphorylates YY1 in vitro and in vivo at threonine 39 in the activation domain. We show that this phosphorylation is cell cycle regulated and peaks at G2/M. This is the first report identifying a kinase for which YY1 is a substrate

Development of magnetic nanoparticle based calorimetric assay for the detection of bovine mastitis in cow milk

Mastitis in dairy cattle is an inflammatory reaction of the udder tissue. Mastitis increases plasmin levels, leading to an increased proteolysis of milk proteins such as casein, resulting in a significant decrease in milk quality and related dairy products. Due to its key-role in mastitis, we used plasmin proteolytic activity as a biomarker for the detection of mastitis in bovine mastitic milk. Inspired by earlier studies on protease activity using mastitic milk samples, we developed a simple colorimetric assay to distinguish mastitic milk from milk derived from healthy animals. The plasmin substrate coupled to magnetic nanoparticles form a black self-assembled monolayer on a gold sensor surface. In the presence of increased levels of plasmin, the substrate is cleaved and the peptide fragment attached to the magnetic beads, will be attracted by the magnet which is present under the sensor strips revealing the golden surface. We found the area of the golden color surface proportional to plasmin activity. The sensitivity of this method was determined to be 1 ng/ml of plasmin in vitro. Next, we tested the biosensor using mastitis positive milk of which infection is confirmed by bacterial cultures. This newly developed colorimetric biosensor has high potential in applications for the diagnosis of mastitis with potential spin offs to health, food and environmental sectors

Si-containing 3D cage-functionalized graphene oxide grafted with Ferrocene for high-performance supercapacitor application: An experimental and theoretical study

In this work, graphene oxide sheets were functionalized with Octa(aminopropyl)silsesquioxane. Then, Octa(aminopropyl)silsesquioxane-functionalized graphene oxide (GO-Amine-SSQ) was grafted with Ferrocene through Friedel-Craft reaction. Structural properties of the prepared composite (GO-Amine-SSQ-Fc) were analyzed by XPS, FT-IR, XRD, Raman, SEM, TEM, and BET tests. Results confirmed the successful synthesis and high porosity. Next, the electrochemical properties of GO-Amine-SSQ-Fc were characterized by CV, GCD, and EIS techniques in the 3E system. The GO-Amine-SSQ-Fc electrode showed a specific capacitance of 574 F g−1 at 1 A g−1, retention capacitance of 90.1% after 10,000 charge-discharge cycles, low resistance, and efficient diffusion of ions. After confirming the excellent electrochemical performance of this electrode, a symmetric supercapacitor system (GO-Amine-SSQ-Fc//GO-Amine-SSQ-Fc) was tested by CV and GCD techniques, to determine practical application of system. GO-Amine-SSQ-Fc//GO- Amine-SSQ-Fc system recorded a specific capacitance of 304 F g−1 at 0.5 A g−1, retention capacitance of 92.5% over 10,000 charge-discharge cycles, and specific energy of 10.14 Wh kg−1 at a specific power of 500 W kg−1. Also, the results of computational methodology show that the interaction of SSQ, Fc and GO layer in GO-Amine-SSQ-Fc composite, makes it effective as an electrode material for supercapacitors. This excellent performance, as a result of the unique structure of Amine-SSQ groups and the superior electrochemical behavior of Ferrocene groups, suggests that GO-Amine-SSQ-Fc composite has great potential for energy storage devices