Cellular and Immunobiology
Karl H. Pang, Nadir I. Osman, James W.F. Catto, Christopher R. Chapple in Basic Urological Sciences, 2021
The cell contains fluid and intracellular structures enclosed by a lipid membrane. The cell contains fluid (cytoplasm) and intracellular structures enclosed by a lipid membrane. Phospholipid bilayer derived from fatty acids with a hydrophobic core and a hydrophilic exterior. Proteins are found within the membrane and can freely move within it. Important roles of these proteins include: Transport receptors, enzymes, and adhesion molecules. Some amino acids can be synthesised (non-essential), but often not quickly enough to meet bodily demands. These may be included in the essential category. Lipids are made from fatty acids which form a chain—the longer the chain, the less water soluble it is. Cells need to be able to replicate accurately without coding errors, which can affect cellular function. Death occurs when the cell has aged or has suffered an insult, rendering it unable to function.
Delivery Systems for Proteins and Peptides
Munmaya K. Mishra in Applications of Encapsulation and Controlled Release, 2019
Peptides and proteins have become the drugs of choice for the treatment of numerous diseases as a result of their incredible selectivity and their ability to provide effective and potent action. The drug delivery systems (DDSs) has to be able to bind the therapeutic protein/peptide in a fashion that does not affect its bioactivity but holds it sufficiently until the DDS reaches its site of action and releases the protein/peptide in a controlled, sustained manner. This chapter aims to present ongoing research on DDSs for proteins and peptides in an informative way and the targeted delivery of such protein and peptide DDSs. A liposome is a spherical vesicle with a membrane composed of a phospholipid bilayer used to deliver a drug or genetic material into a cell. A microparticulate delivery system based on a thiolated chitosan conjugate was developed for the nasal application of peptides. Insulin was used as the model peptide.
Morphology of Bifidobacteria
Anatoly Bezkorovainy, Robin Miller-Catchpole in Biochemistry and Physiology of Bifidobacteria, 2020
Bifidobacteria were first characterized by their unusual shape. They were originally described in 1899 by Tissier, as Gram-positive, curved or bifid, rod-shaped bacteria, which varied in shape when growing in different media. The size of bifidobacteria, like other bacteria, is dependent on growth rate. Bacteria from the log phase of growth may be both larger and more variable in size than those in the experimental stationary phase. The genus Bifidobacterium has a pleomorphic cellular morphology that is dependent not only on the individual species, but on the media in which it is grown. B. bifidum is a Gram-positive, curved rod with a bifurcated end, giving a characteristic Y shape when present in the stool of the breast-fed infant. The cytoplasmic membrane of bifidobacteria conforms to the model of other cell membranes, a fluid phospholipid bilayer with globular protein molecules embedded in it.
Dorzolamide nanoliposome as a long action ophthalmic delivery system in open angle glaucoma and ocular hypertension patients
Published in Drug Development and Industrial Pharmacy, 2018
Maryam Kouchak, Mohammad Malekahmadi, Neda Bavarsad, Amal Saki Malehi, Laleh Andishmand
Importance: To reduce the frequency of dorzolamide eye drop administration and increasing the duration of action. Background: This study aims to compare the effect of dorzolamide loaded-nanoliposome with marketed dorzolamide HCl eye drop on intraocular pressure in primary open angle glaucoma and ocular hypertension patients. Design: A randomized study was conducted in a hospital. Participants: Twenty patients with primary open angle glaucoma or ocular hypertension (in both eyes) diagnosis were recruited as participants. Methods: Dorzolamide loaded-nanoliposome was prepared by thin layer hydration method and characterized. Intra ocular pressure were compared between the two groups who received marketed dorzolamide solution or dorzolamide-loaded nanoliposome. Main outcome measures: The main outcome measures include intraocular pressure initially (day 0) and on days 14 and 28 and adverse effect of dorzolamide-loaded nanoliposome eye drop. Results: Based on the results of repeated measure, intra ocular pressure was seen to decrease in both the groups. But these reductions in the intervention group (dorzolamide-loaded eye drop) were significantly higher than those in control group (p
Analysis of membrane permeability due to synergistic effect of controlled shock wave and electric field application
Published in Electromagnetic Biology and Medicine, 2020
Shadeeb Hossain, Ahmed Abdelgawad
Controlled shock wave has its application in drug delivery via induced membrane permeability. The magnitude of the impulse force to influence the membrane permeability can be abridged via communion effect of shock wave and external applied electric field of reduced threshold. Controlled shock wave have application at targeting membrane site and are used in drug delivery. Electric field influences the phospholipid bilayer structure by creating transient nanometer-sized pores and has application in targeted chemotherapeutic drug delivery. The synergistic input compensates for increased membrane permeability, reduced threshold magnitude and time for transient poration. The hypothesis is analyzed via Molecular Dynamic (MD) simulation. MARTINI coarse grain force field is used to evaluate the changes in the permeability region of the Dipalmitoyl phosphatidylcholine (DPPC) bilayers during the effect. DPPC has been used in the previous literature to model biological membranes. The hydrophobic DPPC region showed an increased permeability during the synergistic effect via transient nanopores formed due to the perturbation. The study of the time-variant synergistic effect will allow molecular-level understanding of the dynamics of the cell membrane permeability for future drug delivery procedure.
Liposome: composition, characterisation, preparation, and recent innovation in clinical applications
Published in Journal of Drug Targeting, 2019
Kamel S. Ahmed, Saied A. Hussein, Abdelmoneim H. Ali, Sameh A. Korma, Qiu Lipeng, Chen Jinghua
In the last decades, pharmaceutical interested researches aimed to develop novel and innovative drug delivery techniques in the medical and pharmaceutical fields. Recently, phospholipid vesicles (Liposomes) are the most known versatile assemblies in the drug delivery systems. The discovery of liposomes arises from self-forming enclosed phospholipid bilayer upon coming in contact with the aqueous solution. Liposomes are uni or multilamellar vesicles consisting of phospholipids produced naturally or synthetically, which are readily non-toxic, biodegradable, and are readily produced on a large scale. Various phospholipids, for instance, soybean, egg yolk, synthetic, and hydrogenated phosphatidylcholine consider the most popular types used in different kinds of formulations. This review summarises liposomes composition, characterisation, methods of preparation, and their applications in different medical fields including cancer therapy, vaccine, ocular delivery, wound healing, and some dermatological applications.
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