Cellular interactions of nanoparticles within the vasculature

2022 ◽  
pp. 247-263
Author(s):  
Azziza Zaabalawi ◽  
May Azzawi
Author(s):  
J. P. Revel

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.


Author(s):  
N. P. Dmitrieva

One of the most characteristic features of cancer cells is their ability to metastasia. It is suggested that the modifications of the structure and properties of cancer cells surfaces play the main role in this process. The present work was aimed at finding out what ultrastructural features apear in tumor in vivo which removal of individual cancer cells from the cell population can provide. For this purpose the cellular interactions in the normal human thyroid and cancer tumor of this gland electron microscopic were studied. The tissues were fixed in osmium tetroxide and were embedded in Araldite-Epon.In normal human thyroid the most common type of intercellular contacts was represented by simple junction formed by the parallelalignment of adjacent cell membranees leaving in between an intermembranes space 15-20 nm filled with electronlucid material (Fig. 1a). Sometimes in the basal part of cells dilatations of the intercellular space 40-50 nm wide were found (Fig. 1a). Here the cell surfaces may form single short microvilli.


Author(s):  
M.E. Rosenfeld ◽  
C. Karboski ◽  
M.F. Prescott ◽  
P. Goodwin ◽  
R. Ross

Previous research documenting the chronology of the cellular interactions that occur on or below the surface of the endothelium during the initiation and progression of arterial lesions, primarily consisted of descriptive studies. The recent development of lower cost image analysis hardware and software has facilitated the collection of high resolution quantitative data from microscopic images. In this report we present preliminary quantitative data on the sequence of cellular interactions that occur on the endothelium during the initiation of atherosclerosis or vasculitis utilizing digital analysis of images obtained directly from the scanning electron microscope. Segments of both atherosclerotic and normal arteries were obtained from either diet-induced or endogenously (WHHL) hypercholesterolemic rabbits following 1-4 months duration of hypercholesterolemia and age matched control rabbits. Vasculitis was induced in rats following placement of an endotoxin soaked thread adjacent to the adventitial surface of arteries.


2019 ◽  
Vol 19 (6) ◽  
pp. 413-425 ◽  
Author(s):  
Athanasios Alexiou ◽  
Stylianos Chatzichronis ◽  
Asma Perveen ◽  
Abdul Hafeez ◽  
Ghulam Md. Ashraf

Background:Latest studies reveal the importance of Protein-Protein interactions on physiologic functions and biological structures. Several stochastic and algorithmic methods have been published until now, for the modeling of the complex nature of the biological systems.Objective:Biological Networks computational modeling is still a challenging task. The formulation of the complex cellular interactions is a research field of great interest. In this review paper, several computational methods for the modeling of GRN and PPI are presented analytically.Methods:Several well-known GRN and PPI models are presented and discussed in this review study such as: Graphs representation, Boolean Networks, Generalized Logical Networks, Bayesian Networks, Relevance Networks, Graphical Gaussian models, Weight Matrices, Reverse Engineering Approach, Evolutionary Algorithms, Forward Modeling Approach, Deterministic models, Static models, Hybrid models, Stochastic models, Petri Nets, BioAmbients calculus and Differential Equations.Results:GRN and PPI methods have been already applied in various clinical processes with potential positive results, establishing promising diagnostic tools.Conclusion:In literature many stochastic algorithms are focused in the simulation, analysis and visualization of the various biological networks and their dynamics interactions, which are referred and described in depth in this review paper.


2020 ◽  
Vol 21 (18) ◽  
pp. 6623 ◽  
Author(s):  
Marc Bienz ◽  
Salima Ramdani ◽  
Hans Knecht

Our understanding of the tumorigenesis of classical Hodgkin lymphoma (cHL) and the formation of Reed–Sternberg cells (RS-cells) has evolved drastically in the last decades. More recently, a better characterization of the signaling pathways and the cellular interactions at play have paved the way for new targeted therapy in the hopes of improving outcomes. However, important gaps in knowledge remain that may hold the key for significant changes of paradigm in this lymphoma. Here, we discuss the past, present, and future of cHL, and review in detail the more recent discoveries pertaining to genetic instability, anti-apoptotic signaling pathways, the tumoral microenvironment, and host-immune system evasion in cHL.


2021 ◽  
Vol 22 (14) ◽  
pp. 7588
Author(s):  
Zoltan Gombos ◽  
Erika Koltai ◽  
Ferenc Torma ◽  
Peter Bakonyi ◽  
Attila Kolonics ◽  
...  

Despite the intensive investigation of the molecular mechanism of skeletal muscle hypertrophy, the underlying signaling processes are not completely understood. Therefore, we used an overload model, in which the main synergist muscles (gastrocnemius, soleus) of the plantaris muscle were surgically removed, to cause a significant overload in the remaining plantaris muscle of 8-month-old Wistar male rats. SIRT1-associated pro-anabolic, pro-catabolic molecular signaling pathways, NAD and H2S levels of this overload-induced hypertrophy were studied. Fourteen days of overload resulted in a significant 43% (p < 0.01) increase in the mass of plantaris muscle compared to sham operated animals. Cystathionine-β-synthase (CBS) activities and bioavailable H2S levels were not modified by overload. On the other hand, overload-induced hypertrophy of skeletal muscle was associated with increased SIRT1 (p < 0.01), Akt (p < 0.01), mTOR, S6 (p < 0.01) and suppressed sestrin 2 levels (p < 0.01), which are mostly responsible for anabolic signaling. Decreased FOXO1 and SIRT3 signaling (p < 0.01) suggest downregulation of protein breakdown and mitophagy. Decreased levels of NAD+, sestrin2, OGG1 (p < 0.01) indicate that the redox milieu of skeletal muscle after 14 days of overloading is reduced. The present investigation revealed novel cellular interactions that regulate anabolic and catabolic processes in the hypertrophy of skeletal muscle.


Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 596
Author(s):  
Christian Jorgensen ◽  
Matthieu Simon

Joint-on-a-chip is a new technology able to replicate the joint functions into microscale systems close to pathophysiological conditions. Recent advances in 3D printing techniques allow the precise control of the architecture of the cellular compartments (including chondrocytes, stromal cells, osteocytes and synoviocytes). These tools integrate fluid circulation, the delivery of growth factors, physical stimulation including oxygen level, external pressure, and mobility. All of these structures must be able to mimic the specific functions of the diarthrodial joint: mobility, biomechanical aspects and cellular interactions. All the elements must be grouped together in space and reorganized in a manner close to the joint organ. This will allow the study of rheumatic disease physiopathology, the development of biomarkers and the screening of new drugs.


Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 397
Author(s):  
Gradimir Misevic ◽  
Emanuela Garbarino

Glycan-to-glycan binding was shown by biochemical and biophysical measurements to mediate xenogeneic self-recognition and adhesion in sponges, stage-specific cell compaction in mice embryos, and in vitro tumor cell adhesion in mammals. This intermolecular recognition process is accepted as the new paradigm accompanying high-affinity and low valent protein-to-protein and protein-to-glycan binding in cellular interactions. Glycan structures in sponges have novel species-specific sequences. Their common features are the large size >100 kD, polyvalency >100 repeats of the specific self-binding oligosaccharide, the presence of fucose, and sulfated and/or pyruvylated hexoses. These structural and functional properties, different from glycosaminoglycans, inspired their classification under the glyconectin name. The molecular mechanism underlying homophilic glyconectin-to-glyconectin binding relies on highly polyvalent, strong, and structure-specific interactions of small oligosaccharide motifs, possessing ultra-weak self-binding strength and affinity. Glyconectin localization at the glycocalyx outermost cell surface layer suggests their role in the initial recognition and adhesion event during the complex and multistep process. In mammals, Lex-to-Lex homophilic binding is structure-specific and has ultra-weak affinity. Cell adhesion is achieved through highly polyvalent interactions, enabled by clustering of small low valent structure in plasma membranes.


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