Polyreactive antibodies bind to a variety of structurally unrelated antigens. The function of these antibodies, however, has remained an enigma, and because of their low binding affinity their biological relevance has been questioned. Using a panel of monoclonal polyreactive antibodies, we showed that these antibodies can bind to both Gram-negative and Gram-positive bacteria and acting through the classical complement pathway can inhibit bacterial growth by lysis, generate anaphylatoxin C5a, enhance phagocytosis, and neutralize the functional activity of endotoxin. Polyreactive antibody-enriched, but not polyreactive antibody-reduced, IgM prepared from normal human serum displays antibacterial activity similar to that of monoclonal polyreactive IgM. We conclude that polyreactive antibodies are a major contributor to the broad antibacterial activity of the natural antibody repertoire.
Summarizing the status of drugs in the market and examining the trend of drug research and development is important in drug discovery. In this study, we compared the drug targets and the market sales of the new molecular entities approved by the U.S. Food and Drug Administration from January 2000 to December 2009. Two networks, namely, the target–target and drug–drug networks, have been set up using the network analysis tools. The multi-target drugs have much more potential, as shown by the network visualization and the market trends. We discussed the possible reasons and proposed the rational strategies for drug research and development in the future.
With the increasing research and development (R&D) difficulty of new molecular entities (NMEs), novel drug delivery systems (DDSs) are attracting widespread attention. This review investigated the current distribution of Food and Drug Administration (FDA)-approved pharmaceutical products and evaluated the technical barrier for the entry of generic drugs and highlighted the success and failure of advanced drug delivery systems. According to the ratio of generic to new drugs and the four-quadrant classification scheme for evaluating the commercialization potential of DDSs, the results showed that the traditional dosage forms (e.g., conventional tablets, capsules and injections) with a lower technology barrier were easier to reproduce, while advanced drug delivery systems (e.g., inhalations and nanomedicines) with highly technical barriers had less competition and greater market potential. Our study provides a comprehensive insight into FDA-approved products and deep analysis of the technical barriers for advanced drug delivery systems. In the future, the R&D of new molecular entities may combine advanced delivery technologies to make drug candidates into more therapeutically effective formulations.
Racemic phenanthroindolizidine alkaloids tylophorine, antofine, and deoxytylophorinine, and optically pure alkaloids S-(+)-tylophorine and R-(-)-tylophorine were synthesized and evaluated for their antiviral activities against tobacco mosaic virus (TMV). Further salinization modifications based on tylophorine increased stability and water solubility and improved the antiviral activity in application. The bioassay results showed that most of these synthesized compounds showed higher antiviral activity against TMV in vitro and in vivo than commercial Ningnanmycin. Especially, tylophorine salt derivatives 10, 11, 13, 17, and 22 emerged as potential inhibitors of plant virus. These findings demonstrate that these phenanthroindolizidine alkaloids and their salt derivatives represent a new template for antiviral studies and could be considered for novel therapy against plant virus infection.
The role of glycocalyx in blood-brain barrier (BBB) integrity and brain damage is poorly understood. Our study aimed to investigate the impacts of endothelial glycocalyx on BBB function in a rat model of cardiac arrest (CA) and cardiopulmonary resuscitation (CPR). Male Sprague-Dawley rats subjected to 8-min asphyxia CA/CPR. Compared to controls, glycocalyx was mildly injured by CA, severely disrupted by hyaluronidase (HAase) with CA, and mitigated by hydrocortisone (HC) with CA. More importantly, the disruption of glycocalyx caused by HAase treatment was associated with higher BBB permeability and aggravated brain edema at 24 h after return of spontaneous circulation, as well as lower survival rate and poorer neurologic outcome at seventh day. Reversely, less degradation of glycocalyx by HC treatment was accompanied by higher seven-day survival rate and better neurologic outcome. Mechanistically, HAase treatment further increased CA/CPR-induced activation of glia cells and expression of inflammatory factors, whereas HC decreased them in the brain cortex and hippocampus. Glycocalyx degradation results in BBB leakage, brain edema, and deteriorates neurologic outcome after asphyxia CA/CPR in rats. Preservation of glycocalyx by HC could improve neurologic outcome and reduce BBB permeability, apparently through reduced gene transcription-protein synthesis and inflammation.
Scherngell T. and Hu Y. Collaborative knowledge production in China: regional evidence from a gravity model approach, Regional Studies. This study investigates collaborative knowledge production in China from a regional perspective. The objective is to illustrate spatial patterns of research collaborations between thirty-one Chinese regions, and to estimate the impact of geographical, technological, and economic factors on the variation of cross-region collaboration activities within a negative binomial gravity model framework. Data are used on Chinese scientific publications from 2007 with multiple author addresses coming from the China National Knowledge Infrastructure (CNKI) database. The results provide evidence that geographical space impedes cross-region research collaborations in China. Technological proximity matters more than geography, while economic effects only play a minor role. [image omitted] Scherngell T. et Hu Y. La production en collaboration de la connaissance en Chine; des preuves regionales provenant d'un modele de gravite, Regional Studies. Cette etude examine la production en collaboration de la connaissance en Chine d'un point de vue regional. On cherche a illustrer les tendances geographiques de la recherche en collaboration pour trente et une regions chinoises et a estimer l'impact des facteurs a la fois geographiques, technologiques et economiques sur la variation des activites de collaboration interregionales au sein d'un modele de gravite du type binomial negatif. On emploie des donnees sur les publications scientifiques chinoises de 2007 dont les adresses a auteur multiples proviennent de la base de donnees China National Knowledge Infrastructure (CNKI). Les resultats laissent voir que l'espace geographique fait obstacle a la recherche interregionale en collaboration en Chine. La proximite de la technologie l'emporte sur la geographie, tandis que les retombees economiques ne jouent qu'un role secondaire. Publication en collaboration Production de la connaissance en collaboration Modele de gravite regional binomial negatif Regions chinoises Scherngell T. und Hu Y. Kollaborative Wissensproduktion in China: eine empirische Analyse mit raumlichen Interaktionsmodellen, Regional Studies. Die vorliegende Studie untersucht kollaborative Wissensproduktion in China aus einer regionalen Perspektive. Zielsetzung ist es, raumliche Muster kollaborativer Wissensproduktion zwischen 31 chinesischen Regionen zu beschreiben und den Einfluss von geographischen, technologischen und okonomischen Determinanten auf die Variation interregionaler Kollaborationsaktiviaten zu messen. Die Studie verwendet neue Daten aus der China National Knowledge Infrastructure (CNKI) Datenbank uber chinesische Ko-Publikationen mit mindestens zwei Autoren aus dem Jahr 2007. Die Ergebnisse zeigen, dass die Kollaborationswahrscheinlichkeit signifikant mit zunehmender geographischer Distanz abnimmt. Der Einfluss von technologischer Nahe ist jedoch wichtiger als geographische Distanzeffekte, wahrend okonomische Unterschiede eine g...
The activity of Cdk5-p35 is tightly regulated in the developing and mature nervous system. Stress-induced cleavage of the activator p35 to p25 and a p10 N-terminal domain induces deregulated Cdk5 hyperactivity and perikaryal aggregations of hyperphosphorylated Tau and neurofilaments, pathogenic hallmarks in neurodegenerative diseases, such as Alzheimer disease and amyotrophic lateral sclerosis, respectively. Previously, we identified a 125-residue truncated fragment of p35 called CIP that effectively and specifically inhibited Cdk5-p25 activity and Tau hyperphosphorylation induced by A peptides in vitro, in HEK293 cells, and in neuronal cells. Although these results offer a possible therapeutic approach to those neurodegenerative diseases assumed to derive from Cdk5-p25 hyperactivity and/or A induced pathology, CIP is too large for successful therapeutic regimens. To identify a smaller, more effective peptide, in this study we prepared a 24-residue peptide, p5, spanning CIP residues Lys 245 -Ala 277 . p5 more effectively inhibited Cdk5-p25 activity than did CIP in vitro. In neuron cells, p5 inhibited deregulated Cdk5-p25 activity but had no effect on the activity of endogenous Cdk5-p35 or on any related endogenous cyclin-dependent kinases in HEK293 cells. Specificity of p5 inhibition in cortical neurons may depend on the p10 domain in p35, which is absent in p25. Furthermore, we have demonstrated that p5 reduced A(1-42)-induced Tau hyperphosphorylation and apoptosis in cortical neurons. These results suggest that p5 peptide may be a unique and useful candidate for therapeutic studies of certain neurodegenerative diseases.The activity of Cdk5, a multifunctional serine/threonine kinase, is critical for neuronal development and synaptic activity; it sustains neurite outgrowth, neuronal migration, cortical lamination, and survival (1-9). Its activity depends on the binding of its neuron-specific, cyclin-related activators, p35 and p39 (10, 11). Cdk5 has also been implicated as a key player in learning and memory (12-15).Normally, Cdk5 activity is tightly regulated, but under conditions of neuronal stress, it is deregulated, leading to hyperactivity, neuronal pathology, and cell death. Accordingly, Cdk5 has been implicated in certain neurodegenerative disorders, such as AD.2 A model of the role of Cdk5 in neurodegeneration suggests that a stress-induced influx of calcium ions into neurons activates calpain, a Ca 2ϩ -activated protease, which cleaves p35 into p25 and a p10 fragment. p25, in turn, forms a more stable Cdk5-p25 hyperactive complex, which hyperphosphorylates Tau and induces cell death (16 -21). Indeed, increased levels of p25 and Cdk5 activity have been reported in AD brains. The finding that p25 may be toxic comes from studies of cortical neurons treated with -amyloid (A), a key marker of AD pathology, where p35 is converted to p25 accompanied by activated Cdk5, Tau hyperphosphorylation, and apoptosis (22,23).Expression of the Cdk5-p25 complex seems to be primarily responsible for the Tau pathology ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.