Some Aspects of the Polyhexamethyleneguanidine Salts Effect on Cell Cultures

2014 ◽  
Vol 1 (1) ◽  
pp. 62-67 ◽  
Author(s):  
M. Mandygra ◽  
A. Lysytsia
Keyword(s):  
Proliferative Activity ◽  
Cell Monolayer ◽  
Eukaryotic Cell ◽  
Culture Methods ◽  
Cellular Processes ◽  
Negative Effect ◽  
Membrane Bound ◽  
Membrane Bound Enzymes ◽  
Anion Type ◽  
Cell Culture Methods

Aim. To investigate the effect of polyhexamethyleneguanidine (PHMG) to eukaryotic cell culture. Methods. The passaged bovine tracheal cells culture (TCC) and primary culture of chicken embryo fi broblasts (FCE) were used in the experiments. TCC and FCE monolayers were treated with aqueous solutions of PHMG chloride or succinate. The method of PHMG polycation adsorption to the cells’ plasma membrane together with microscopy were applied. Results. The dependence of PHMG effect on the eukaryotic cells on the agent concentration, duration of exposure and the anion type has been fi xed. The PHMG concentration of 10 –5 per cent (0.1 μg/ml) never causes degradation of the previously formed cell monolayer, while the higher concentrations damage it. The conditions of the PHMG chloride and succinate’s negative effect on cell proliferation and inhibition of monolayer formation were determined. The hypothesis that under certain conditions PHMG stimulates the proliferative activity of the cells has been confi rmed. Stimulation may be associated with non-specifi c stress adaptation of cells. In this case, it is due to modifi cations of the cell membrane after PHMG adsorption to it. Conclusions. PHMG polycation binds with the membrane’s phosphoglycerides fi rmly and irreversibly. A portion of the lipids are removed from participation in the normal cellular processes at that. At the same time, the synthesis of new lipids and membrane-bound enzymes is probably accelerated. The phospholip ids’ neogenesis acceleration can stimulate mitosis under certain conditions. The obtained results can be used in the biotechnologies.

scholarly journals Bend, Push, Stretch: Remarkable Structure and Mechanics of Single Intermediate Filaments and Meshworks

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1960
Author(s):  
K. Tanuj Sapra ◽  
Ohad Medalia
Keyword(s):  
Intermediate Filaments ◽  
Eukaryotic Cell ◽  
Coiled Coils ◽  
Cellular Functions ◽  
Mechanical Pressure ◽  
Mechanical Feature ◽  
Cellular Processes ◽  
Nuclear Lamins ◽  
Filament Networks ◽  
And Function

The cytoskeleton of the eukaryotic cell provides a structural and functional scaffold enabling biochemical and cellular functions. While actin and microtubules form the main framework of the cell, intermediate filament networks provide unique mechanical properties that increase the resilience of both the cytoplasm and the nucleus, thereby maintaining cellular function while under mechanical pressure. Intermediate filaments (IFs) are imperative to a plethora of regulatory and signaling functions in mechanotransduction. Mutations in all types of IF proteins are known to affect the architectural integrity and function of cellular processes, leading to debilitating diseases. The basic building block of all IFs are elongated α-helical coiled-coils that assemble hierarchically into complex meshworks. A remarkable mechanical feature of IFs is the capability of coiled-coils to metamorphize into β-sheets under stress, making them one of the strongest and most resilient mechanical entities in nature. Here, we discuss structural and mechanical aspects of IFs with a focus on nuclear lamins and vimentin.

scholarly journals Regulation of membrane-bound enzymes of glycosphingolipid biosynthesis

1984 ◽  
Vol 25 (13) ◽  
pp. 1541-1547
Author(s):  
J D Burczak ◽  
R M Soltysiak ◽  
C C Sweeley
Keyword(s):  
Membrane Bound ◽  
Membrane Bound Enzymes ◽  
Glycosphingolipid Biosynthesis

Cell Culture Methods to Evaluate the Biocompatibility of Implant Materials

1992 ◽  
Vol 20 (1) ◽  
pp. 52-60
Author(s):  
Gabriela Ciapetti ◽  
Elisabetta Cenni ◽  
Daniela Cavedagna ◽  
Loredana Pratelli ◽  
Arturo Pizzoferrato
Keyword(s):  
Cell Culture ◽  
Quantitative Data ◽  
Cell Function ◽  
Culture Methods ◽  
Cell Culture Techniques ◽  
Culture Techniques ◽  
Biological Compatibility ◽  
Compatibility Of Materials ◽  
Cell Culture Methods

Cell culture techniques are usually used in the field of biomaterials research and development in order to detect toxic components. Morphological assays are the most widely used methods and give the very first information about the biological compatibility of materials. Cell function assays give more quantitative data, but the comparison of data between different laboratories is difficult. Some of the cell culture methods that are used for biocompatibility studies are described briefly here, and results from our laboratory are reported. Despite some inherent limitations of the cell culture techniques, they are an accurate and reliable method of predicting the biological compatibility of materials to be implanted in vivo.

Retinol dehydrogenases: Membrane-bound enzymes for the visual function

2014 ◽  
Vol 92 (6) ◽  
pp. 510-523 ◽  
Author(s):  
Mustapha Lhor ◽  
Christian Salesse
Keyword(s):  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Membrane Binding ◽  
Large Family ◽  
Structural Features ◽  
Visual Cycle ◽  
Retinoid Metabolism ◽  
Current State ◽  
Membrane Bound ◽  
Membrane Bound Enzymes

Retinoid metabolism is important for many physiological functions, such as differenciation, growth, and vision. In the visual context, after the absorption of light in rod photoreceptors by the visual pigment rhodopsin, 11-cis retinal is isomerized to all-trans retinal. This retinoid subsequently undergoes a series of modifications during the visual cycle through a cascade of reactions occurring in photoreceptors and in the retinal pigment epithelium. Retinol dehydrogenases (RDHs) are enzymes responsible for crucial steps of this visual cycle. They belong to a large family of proteins designated as short-chain dehydrogenases/reductases. The structure of these RDHs has been predicted using modern bioinformatics tools, which allowed to propose models with similar structures including a common Rossman fold. These enzymes undergo oxidoreduction reactions, whose direction is dictated by the preference and concentration of their individual cofactor (NAD(H)/NADP(H)). This review presents the current state of knowledge on functional and structural features of RDHs involved in the visual cycle as well as knockout models. RDHs are described as integral or peripheral enzymes. A topology model of the membrane binding of these RDHs via their N- and (or) C-terminal domain has been proposed on the basis of their individual properties. Membrane binding is a crucial issue for these enzymes because of the high hydrophobicity of their retinoid substrates.

Ultracytochemical localization of membrane-bound enzymes in the node of Ranvier

1989 ◽  
Vol 20 (3-4) ◽  
pp. 207-215
Author(s):  
Kenichirou Inomata ◽  
Fumio Nasu ◽  
Kazuhiro Tomiyasu
Keyword(s):  
Node Of Ranvier ◽  
Membrane Bound ◽  
Membrane Bound Enzymes
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