China
Africa
Explore chapters and articles related to this topic
The cell and tissues
Published in Peate Ian, Dutton Helen, Acute Nursing Care, 2020
As identified earlier, some of the proteins in the plasma membrane cross the full width of the membrane, whereas others penetrate only part of the way through the membrane. Some of the membrane proteins form channels through the cell membrane that, under the right conditions, allow the movement or transport of electrolytes and other lipid-insoluble substances into and out of the cell (see Figure 3.3).
Haematology
Published in Kristen Davies, Shadaba Ahmed, Core Conditions for Medical and Surgical Finals, 2020
The main inherited haemolytic anaemias can be categorised by the affected part of the RBC: Cell membrane: Hereditary spherocytosis/elliptocystosisCell cytoplasm: Glucose-6-phosphate deficiency (G6PD)Haemoglobin: Sickle cell anaemia, thalassaemia
Cell Components and Function
Published in Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal, Principles of Physiology for the Anaesthetist, 2020
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal
The cell membrane is a matrix of the phospholipid bilayer with mobile and randomly distributed integral proteins (fluid mosaic model of Singer and Nicholson). This accounts for the cytoskeletal and extracellular interactions between membrane lipids and proteins which restrict the mobility of membrane structures. The cell membrane can be thought of as a layer of insulation covered on both sides by conducting material. This structure is traversed by protein channels that determine ionic permeability and the resultant electrical potential across the membrane. The functions of the cell membrane include signal transduction, enzymatic activity, transport and immunity.
Advances, challenge and prospects in cell-mediated nanodrug delivery for cancer therapy: a review
Published in Journal of Drug Targeting, 2023
Wuhao Wei, Yuansheng Zhang, Zhizhe Lin, Xin Wu, Wei Fan, Jianming Chen
The cell membrane is made up of thousands of different proteins, carbohydrates and lipids, which have the potential for chemical modification [91]. In addition, the chemical modification does not rely exclusively on naturally available cell surface molecules; the complexity of cell membranes provides options for introducing other functional groups for some conjugation reactions. Unlike pristine cells, modified cells enable convenient conjugations with therapeutics and particles via versatile chemistry tools. For example, thiols on the cell membrane can be used for drug coupling reactions with targeting units such as antibodies and polypeptides [92]. In addition [93], the ligand adhered to NPs through chemical coupling to improve the therapeutic effect by combining the ligand with the ligand on the cell surface.
Glucosamine modulates membrane and cellular ionic homeostasis: studies on accelerated senescent and naturally aged rats
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Komal Saraswat, Raushan Kumar, Syed Ibrahim Rizvi
It has been suggested that biochemical and biophysical abnormalities of cell membranes may actively participate in the pathogenesis of age-related diseases [27]. Membrane-bound calcium-transporting protein PMCA pump is important in regulating various signaling functions of calcium [31]. Erythrocytes have deformability and elasticity properties which are affected by Ca2+ ions [32]. Elevation in internal Ca2+ levels leads to changes in cell shape and volume, increased cellular rigidity, and hemolysis [33]. Since this pump plays a crucial role in the maintenance of internal Ca2+ levels by creating a concentration gradient between cytosol and extracellular fluid, it can be predicted that aging results in alteration of PMCA pump activity [34]. Altered activity of erythrocyte PMCA has been reported in aging [35] which can be seen in our results too. However, upregulation of PMCA activity by glucosamine supplementation signifies its possible shielding effect against cellular redox imbalance in aging and associated diseases.
Characterising phospholipids and free fatty acids in patients with schizophrenia: A case-control study
Published in The World Journal of Biological Psychiatry, 2021
Dongfang Wang, Xiaoyu Sun, Michel Maziade, Wei Mao, Chuanbo Zhang, Jingyu Wang, Bing Cao
In this study, abnormalities of individual PEs and LPEs were also observed in the serum of SCZ patients with different change trends, although the total PE and LPE levels were not significantly different between SCZ and control groups. PEs is another overwhelming majority of GPLs in both human cell membranes and plasma, containing ethanolamine as an alcohol head group, and its hydrolysis by phospholipase A2 results in the genesis of LPEs. Previous studies on central and peripheral membrane lipid abnormalities of SCZ showed a substantial decrease in PE content (Yao et al. 2000; Ponizovsky et al. 2001; Schmitt et al. 2004; Hamazaki et al. 2010; Ghosh et al. 2017). Our study found that SCZ patients had lower levels of PEs with C18:2 moiety, but higher levels of C16:0, C18:0, C20:4 and C22:6 moieties compared to controls. Among differential LPEs, polyunsaturated LPEs were elevated, but the levels of saturated and monounsaturated LPEs changed inconsistently. Data about metabolic profiling of PEs and LPEs is still quite limited. These abnormalities may refer to changes in lipid transport proteins, and impairments in cell membrane structure and function (Nuss et al. 2009; Dennis et al. 2011). Potential mechanisms underlying these abnormalities and their biological effects need to be further studied.