scholarly journals A multiformalism and multiresolution modelling environment: application to the cardiovascular system and its regulation

Author(s):  
Alfredo I. Hernández ◽  
Virginie Le Rolle ◽  
Antoine Defontaine ◽  
Guy Carrault

The role of modelling and simulation in the systemic analysis of living systems is now clearly established. Emerging disciplines, such as systems biology, and worldwide research actions, such as the Physiome Project or the Virtual Physiological Human, are based on an intensive use of modelling and simulation methodologies and tools. One of the key aspects in this context is to perform an efficient integration of various models representing different biological or physiological functions, at different resolutions, spanning through different scales. This paper presents a multiformalism modelling and simulation environment (M2SL) that has been conceived to ease model integration. A given model is represented as a set of coupled and atomic model components that may be based on different mathematical formalisms with heterogeneous structural and dynamical properties. A co-simulation approach is used to solve these hybrid systems. The pioneering model of the overall regulation of the cardiovascular system proposed by Guyton and co-workers in 1972 has been implemented under M2SL and a pulsatile ventricular model based on a time-varying elastance has been integrated in a multi-resolution approach. Simulations reproducing physiological conditions and using different coupling methods show the benefits of the proposed environment.

Author(s):  
Elias B. Sayah ◽  
Kishor P

This research presented a practically achievable scenario of a smart warehouse receiving smart containers to be inspected smartly and effectively. This research had four objectives: review role of augmented and virtual realities in construction warehousing; define a scenario in an example construction warehousing layout and create modelling and simulation environment in Blender; simulate the scenario in interactive mode and record the features and experiences; and make recommendations for its practical implementation. A 3D model of an example scenario of inspection of containers was created in Blender software, and its Augmented Reality (AR) functionalities were configured for a simulated experience. An example process of inspection of the containers offloaded in a temporary construction warehouse was experienced within the 3D model and key features and experiences were recorded.


2018 ◽  
Vol 24 (20) ◽  
pp. 2283-2302 ◽  
Author(s):  
Vivian B. Neis ◽  
Priscila B. Rosa ◽  
Morgana Moretti ◽  
Ana Lucia S. Rodrigues

Heme oxygenase (HO) family catalyzes the conversion of heme into free iron, carbon monoxide and biliverdin. It possesses two well-characterized isoforms: HO-1 and HO-2. Under brain physiological conditions, the expression of HO-2 is constitutive, abundant and ubiquitous, whereas HO-1 mRNA and protein are restricted to small populations of neurons and neuroglia. HO-1 is an inducible enzyme that has been shown to participate as an essential defensive mechanism for neurons exposed to oxidant challenges, being related to antioxidant defenses in certain neuropathological conditions. Considering that neurodegenerative diseases (Alzheimer’s Disease (AD), Parkinson’s Disease (PD) and Multiple Sclerosis (MS)) and neuropsychiatric disorders (depression, anxiety, Bipolar Disorder (BD) and schizophrenia) are associated with increased inflammatory markers, impaired redox homeostasis and oxidative stress, conditions that may be associated with alterations in HO-levels/activity, the purpose of this review is to present evidence on the possible role of HO-1 in these Central Nervous System (CNS) diseases. In addition, the possible therapeutic potential of targeting brain HO-1 is explored in this review.


2020 ◽  
Vol 18 (3) ◽  
pp. 204-214 ◽  
Author(s):  
Aida Habib ◽  
Giovanna Petrucci ◽  
Bianca Rocca

<P>Under physiological conditions, peripheral arteries release endogenous vascular-protective and antithrombotic agents. Endothelial cells actively synthesize vasoactive mediators, which regulate vascular tone and platelet reactivity thus preventing thrombosis. Atherosclerosis disrupts homeostasis and favours thrombosis by triggering pro-thrombotic responses in the vessels, platelet activation, aggregation as well as vasoconstriction, phenomena that ultimately lead to symptomatic lumen restriction or complete occlusion. <P> In the present review, we will discuss the homeostatic role of arterial vessels in releasing vascular-protective agents, such as nitric oxide and prostacyclin, the role of pro- and anti-thrombotic vascular receptors as well as the contribution of circulating platelets and coagulation factors in triggering the pro-thrombotic response(s). We will discuss the pathological consequences of disrupting the protective pathways in the arteries and the pharmacological interventions along these pathways.</P>


Author(s):  
Adrián Yoris ◽  
Adolfo M. García ◽  
Paula Celeste Salamone ◽  
Lucas Sedeño ◽  
Indira García-Cordero ◽  
...  

Dimensional and transdiagnostic approaches have revealed multiple cognitive/emotional alterations shared by several neuropsychiatric conditions. While this has been shown for externally triggered neurocognitive processes, the disruption of interoception across neurological disorders remains poorly understood. This chapter aims to fill this gap while proposing cardiac interoception as a potential common biomarker across disorders. It focuses on key aspects of interoception, such as the mechanisms underlying different interoceptive dimensions; the relationship among interoception, emotion, and social cognition; and the roles of different interoceptive pathways. It considers behavioral and brain evidence in the context of an experimental and clinical agenda to evaluate the potential role of interoception as a predictor of clinical outcomes, a marker of neurocognitive deficits across diseases, and a general source of insights for breakthroughs in the treatment and prevention of multiple disorders. Finally, future directions to improve the dimensional and transdiagnostic assessment of interoception are outlined.


2021 ◽  
Vol 22 (6) ◽  
pp. 2864
Author(s):  
Anna Pulawska-Czub ◽  
Tomasz D. Pieczonka ◽  
Paula Mazurek ◽  
Krzysztof Kobielak

Nails are highly keratinized skin appendages that exhibit continuous growth under physiological conditions and full regeneration upon removal. These mini-organs are maintained by two autonomous populations of skin stem cells. The fast-cycling, highly proliferative stem cells of the nail matrix (nail stem cells (NSCs)) predominantly replenish the nail plate. Furthermore, the slow-cycling population of the nail proximal fold (nail proximal fold stem cells (NPFSCs)) displays bifunctional properties by contributing to the peri-nail epidermis under the normal homeostasis and the nail structure upon injury. Here, we discuss nail mini-organ stem cells’ location and their role in skin and nail homeostasis and regeneration, emphasizing their importance to orchestrate the whole digit tip regeneration. Such endogenous regeneration capabilities are observed in rodents and primates. However, they are limited to the region adjacent to the nail’s proximal area, indicating the crucial role of nail mini-organ stem cells in digit restoration. Further, we explore the molecular characteristics of nail mini-organ stem cells and the critical role of the bone morphogenetic protein (BMP) and Wnt signaling pathways in homeostatic nail growth and digit restoration. Finally, we investigate the latest accomplishments in stimulating regenerative responses in regeneration-incompetent injuries. These pioneer results might open up new opportunities to overcome amputated mammalian digits and limbs’ regenerative failures in the future.


2021 ◽  
Vol 22 (14) ◽  
pp. 7436
Author(s):  
Helga Simon-Molas ◽  
Xavier Vallvé-Martínez ◽  
Irene Caldera-Quevedo ◽  
Pere Fontova ◽  
Claudia Arnedo-Pac ◽  
...  

The glycolytic modulator TP53-Inducible Glycolysis and Apoptosis Regulator (TIGAR) is overexpressed in several types of cancer and has a role in metabolic rewiring during tumor development. However, little is known about the role of this enzyme in proliferative tissues under physiological conditions. In the current work, we analysed the role of TIGAR in primary human lymphocytes stimulated with the mitotic agent Concanavalin A (ConA). We found that TIGAR expression was induced in stimulated lymphocytes through the PI3K/AKT pathway, since Akti-1/2 and LY294002 inhibitors prevented the upregulation of TIGAR in response to ConA. In addition, suppression of TIGAR expression by siRNA decreased the levels of the proliferative marker PCNA and increased cellular ROS levels. In this model, TIGAR was found to support the activity of glucose 6-phosphate dehydrogenase (G6PDH), the first enzyme of the pentose phosphate pathway (PPP), since the inhibition of TIGAR reduced G6PDH activity and increased autophagy. In conclusion, we demonstrate here that TIGAR is upregulated in stimulated human lymphocytes through the PI3K/AKT signaling pathway, which contributes to the redirection of the carbon flux to the PPP.


2021 ◽  
pp. 1-14
Author(s):  
Andreas RASCHE ◽  
Sandra WADDOCK

Abstract This article presents a review of the literature on the United Nations Guiding Principles (UNGPs) for the purpose of situating the UNGPs in the voluntary corporate social responsibility (CSR) infrastructure. We identify four key themes that underlie the debate: (1) a critical assessment of the UNGPs, (2) their application to different sectors, (3) a discussion of how to embed key aspects of the UNGPs into national and regional contexts, and (4) reflections on the role of due diligence. We discuss these themes and outline some practical and theoretical take-away messages. Our review highlights some similarities and differences to the discussion of voluntary initiatives in the field of CSR, especially the UN Global Compact. Our discussion helps to understand how the UNGPs are situated in the voluntary institutional infrastructure for CSR. Finally, we show how the theoretical and practical discourse on the UNGPs can be further advanced.


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