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Glove Selection for Work with Acrylates Including Those Cured by Ultraviolet, Visible Light, or Electron Beam
Published in Robert N. Phalen, Howard I. Maibach, Protective Gloves for Occupational Use, 2023
For some specific industrial, medical, or dental applications, the oligomers are manufactured in a more controlled synthetic route to a purer product with narrow molecular weight distribution. Moreover, purification steps may be added to remove impurities such as catalysts and other low-molecular-weight chemicals that will not be incorporated into the polymer network upon cure and/or that might be of toxicological concern.
Immunomodulatory Effect of Plant-Based Extracts on Neurodegeneration
Published in P. Mereena Luke, K. R. Dhanya, Didier Rouxel, Nandakumar Kalarikkal, Sabu Thomas, Advanced Studies in Experimental and Clinical Medicine, 2021
Koel Sinha, Chitrangada Das Mukhopadhyay
GB is beneficial for normal cognitive functions due to its proper antioxidant and vascular properties. Presently, in-vitro reports in rats evidenced that a vital mechanism plays a crucial role in reducing BBB permeability by enhancing the cognitive effects of Ginkgolide-B [54]. Moreover, other studies discovered that EGb-761 leaf extract, prevented brain endothelial damage by beta-amyloid oligomer. This oligomer plays a key role in AD pathogenesis [55]. The study was conducted along with 216 patients and they received either a regular dose of 240 mg EGb 761 or placebo. Besides, the clinical efficacy was done by responder analysis along with therapy response defined as response in two of the three primary variables. On the other hand, human studies with GB leaf extract decreased IL-6 levels in serum of patients with neurologic disorders [50]. Furthermore, one week treatment randomized controlled pilot study revealed that a combining effect of Panax ginseng, Ginkgo biloba, and Crocus sativus elevated the working memory in controls [50].
Nucleic Acids as Therapeutic Targets and Agents
Published in David E. Thurston, Ilona Pysz, Chemistry and Pharmacology of Anticancer Drugs, 2021
Due to their excellent base-pairing properties, backbone-modified oligomers have been used as tools in molecular biology experiments, in diagnostic assays, and also in antigene and antisense therapies as potential anticancer and anti-infective agents.
Effects of water-soluble additive on the release profile and pharmacodynamics of triptorelin loaded in PLGA microspheres
Published in Drug Development and Industrial Pharmacy, 2023
Xiaoyan He, Jiwei Liu, Tao Song, Yiying Sun, Xiaoyan Lu, Nuannuan Li, Kaoxiang Sun
The molecular weight depression of the polymer was determined by the gel permeation chromatography (Figure 8). At the early stage of incubation (the first 3 days), microspheres without additive degraded quickly (F1). For additive containing microspheres, the degradation rate of F2-3, F3-3 and F4-3 was slower but comparable. Water-soluble oligomers were produced while the polymer degraded. The accumulation of acidic oligomers in microspheres will induce autocatalytic degradation of microspheres [13,41]. This will accelerate the degradation of the polymer. Compared with F1, the additive containing microspheres were highly porous (Figure 7). The water-soluble oligomers produced by polymer degradation will be released from the interconnected channels to the release medium. As a result, the autocatalytic degradation of microspheres was inhibited. Hence polymer degradation of F2-3, F3-3 and F4-3 was slower than F1.
Novel strategies for the fight of Alzheimer’s disease targeting amyloid-β protein
Published in Journal of Drug Targeting, 2022
Yang Xie, Yan Wang, Shangfei Jiang, Xiaohong Xiang, Jianhua Wang, Linhong Ning
Dating back to 1984, the amyloid hypothesis (AH) was proposed by Glenner and Wong who firstly isolated Aβ from cerebral cortex of AD patients [35]. Over the past two decades, a range of evidence suggest that excessive aggregation of extracellular Aβ peptides which is the main component in the senile plaques of AD patients' brain, plays a key role in the pathogenesis of AD and it was revealed that cytotoxic effects of Aβ on nerve cells are exert after assembling into soluble oligomers and extracellular fibrils, resulting in neuronal dysfunction and memory loss [36,37]. Compared to soluble amyloid oligomers which are able to spread throughout the brain, larger amyloid fibrils organised as parallel β-sheets are insoluble and further accumulate into amyloid plaques [38]. Later studies revealed that except for the parallel pattern of amyloid fibrils, several segments of Aβ are able to aggregate to an antiparallel pattern [39]. It has been reported that the increased amount of Aβ oligomers in in AD brain extracts implies that Aβ oligomers are probably the major trigger for synapse impairment in the early stage of AD [40,41]. On account of the transient states of Aβ oligomers, structural characterisation of oligomeric Aβ peptides achieved little until the application of experimental method under conditions at low temperature and low salt [42]. Based on the premise that oligomers are the most toxic form of Aβ, oligomer-targeted therapies will bring new opportunities and put forward higher request to AD theranostics.
Interaction of Alpha-Crystallin with Phospholipid Membranes
Published in Current Eye Research, 2021
Laxman Mainali, William J. O’Brien, Raju Timsina
α-crystallin consists of αA- and αB- crystallin subunits with 3 αA to 1 αB molar ratio in adult bovine lens.17 α-crystallin forms highly polydisperse oligomers17,38 in which subunits are known to exchange between the oligomer.38,74-76 This oligomer is a dynamic system where the size of the oligomer changes dynamically by adding or removing the monomer or small oligomers.19,38 Srinivas et al.77 studied the thermal stability of α-crystallin using differential scanning calorimetry and found that the unfolding temperature between 58°C and 61°C for 3:1 heteropolymer and αA-crystallin homopolymer and also observe no precipitation upon thermal unfolding. Based on this thermodynamic stability of α-crystallin, it is very likely that the soluble α-crystallin (not bound to the membrane) is stable at 37°C for 16 hours. We think that the α-crystallin that is in the solution after binding saturation is achieved will interact with membrane bound α-crystallin via subunit exchange. However looking at the higher binding affinity values (Figure 5) we speculate that the subunit exchange takes place only between the soluble α-crystallin and solvent-exposed subunits of membrane bound alpha-crystallin. Previously, Cobb and Petrash16 used fluorescence resonance energy transfer and demonstrated that the subunit exchange takes between solvent exposed regions of membrane bound α-crystallin and the soluble α-crystallin.