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Monographs of Topical Drugs that Have Caused Contact Allergy/Allergic Contact Dermatitis
Published in Anton C. de Groot, Monographs in Contact Allergy, 2021
Nicotine is the primary and a highly toxic alkaloid in tobacco products. It binds stereo-selectively to nicotinic-cholinergic receptors on autonomic ganglia, the adrenal medulla, neuromuscular junctions and in the brain. Nicotine exerts two effects, a stimulant effect exerted at the locus coeruleus and a reward effect in the limbic system. Therefore, nicotine is a highly addictive substance. This agent also induces peripheral vasoconstriction, tachycardia and elevated blood pressure. Nicotine in inhalers and patches is indicated for the relief of nicotine withdrawal symptoms and as an aid to smoking cessation. In pharmaceutical products, both nicotine base and nicotine complexed with methacrylic acid polymer and divinylbenzene (nicotine polacrilex; CAS number 96055-45-7, EC number not available, molecular formula not available) may be employed (1).
T Cell Depletion of Allogeneic Human Bone Marrow Grafts by Soybean Lectin Agglutination and Either Sheep Red Blood Cell Rosetting or Adherence on the CD5/CD8 Cellector™
Published in Adrian P. Gee, BONE MARROW PROCESSING and PURGING, 2020
Nancy H. Collins, Nancy A. Kernan, Sharon A. Bleau, Richard J. O’Reilly
SBA− cells may be depleted of residual T cells by reaction with monoclonal antibodies bound to solid substrates. We have demonstrated in small-scale experiments that treatment of SBA− cells with magnetic monosized polystyrene-divinylbenzene microspheres (4 to 5 μm diameter) directly coated with monoclonal antibodies to the T cell antigens CD2, CD3, and CD8 (Dynal, Inc. Great Neck, NY) results in T cell depletion equivalent to that seen with rosetting. Both rosetting and magnetic bead treatment give greater T cell depletion than treatment of harvested marrow with the rat anti-T cell monoclonal antibody Campath-1 and complement, or the anti-T cell ricin A chain immunotoxin conjugate XomaZyme-H65.22
Drug Analysis of Protein Microspheres: From Pharmaceutical Preparation to In Vivo Fate
Published in Neville Willmott, John Daly, Microspheres and Regional Cancer Therapy, 2020
Jeffrey Cummings, David Watson, John F. Smyth
The most commonly used analytical technique for the determination of FUra is HPLC. The chromophore of FUra is only of moderate strength; this is not a problem with regard to analysis of the drug in formulations. However, when applied to biological fluids many HPLC methods based on ultraviolet detection with chromatography on octadecyl silica gel have a relatively poor sensitivity of ±100 ng/ml. Improved extraction techniques in combination with the use of styrene-divinylbenzene polymeric columns and ion-pairing reagents have yielded HPLC-ultra-violet procedures with limits of detection down to 10 ng/ml.91–93 Extended “cleanup” procedures after extraction also improve sensitivity.94 An advantage of HPLC methods is that they can detect fluoropyrimidines, such as 5′-dFUrd and FUrd, which are not ideal compounds for analysis by gas chromatography. The highest sensitivities afforded by HPLC involve alkylation of FUra with a fluorescent reagent,95,96 and these procedures might be improved further by using column switching to remove excess derivatization reagent. A specialized technique with high sensitivity involves derivatization of FUra to enable chemiluminescence detection.97
Extracorporeal treatment for calcium channel blocker poisoning: systematic review and recommendations from the EXTRIP workgroup
Published in Clinical Toxicology, 2021
Anselm Wong, Robert S. Hoffman, Steven J. Walsh, Darren M. Roberts, Sophie Gosselin, Timothy E. Bunchman, Sofia Kebede, Valery Lavergne, Marc Ghannoum
Several in vitro and ex vivo experiments were performed. Among the most notable in vitro findings, molecular adsorbent recirculating system (MARS®) was better than CVVHDF at removing verapamil because of extensive adsorption to the activated charcoal column [211,214]. As expected from the extensive protein binding of amlodipine, its clearance from hemodialysis was negligible (<5 mL/min) regardless of the dialyzer used [215]; similar conclusions were reached with nifedipine using both hemodialysis and hemoperfusion [204]. Finally, the clearance of verapamil during therapeutic plasma exchange only reached 29.2 mL/min. Two closed loop recirculating bench top experiments studied the effect of hemoperfusion using CytoSorb®, a cartridge containing divinylbenzene co-polymer beads, in which blood concentrations of amlodipine and verapamil were reduced to less than 10% after 180 min [212,213].
Design, synthesis and characterization of enzyme-analogue-built polymer catalysts as artificial hydrolases
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Divya Mathew, Benny Thomas, Karakkattu Subrahmanian Devaky
The crosslinking monomer locks and freezes the position of the template - monomer pre-polymerization complex to a rigid three-dimensional polymer network and preserves the exact geometry of the imprint after its removal. The physicochemical properties and rigidity of MIPs, and hence the substrate selectivity of the polymer depends on the nature and extent of the crosslinking agent to a greater extent [19]. Ethylene glycol dimethacrylate (EGDMA) has proven to be the most efficient crosslinking monomer for methacrylic polymers in molecular recognition. For water compatible systems, N,N-methylene-bis-acrylamide (NNMBA) is found to be the most acceptable one. When the non-polar crosslinker divinylbenzene (DVB) is used, it imparts rigidity and hydrophobicity to the polymer support which increase with increase in crosslinking.
Microspheres of essential oil in polylactic acid and poly(methyl methacrylate) matrices and their blends
Published in Journal of Microencapsulation, 2019
Miroslava Dusankova, Martina Pummerova, Vladimir Sedlarik
Then the appropriate SPME fibre of 65 µm polydimethylsiloxane/divinylbenzene (PDMS/DVB 65) from Supelco was exposed to the liquid sample in headspace vial. After extraction (80 °C for 30 min.), the SPME fibre was removed from the vial and immediately inserted into the gas chromatograph. Conditions for fibre desorption constituted 1 min. at 200 °C.