The modification of gelatin and its combinations with other biomaterials have demonstrated the flexibility of these systems and can be employed for meeting the challenges of finding ideal carrier systems that enable specific, targeted and controlled release in response to demands in the body.
Tissue bioadhesives have raised interest in the last few decades as an alternative to sutures or staples in wound closing applications because of various advantages. They are less time consuming, less painful, and can be less expensive, without compromising the cosmetic outcome. Even though extensive efforts have been made, an ideal tissue adhesive has not been developed to date, mostly because of toxicity or weak bonding strength issues. Novel bioadhesives comprised gelatin and alginate with carbodiimide (N-ethyl-N-(3-dimethylaminopropyl) carbodiimide [EDC]) as the cross-linking agent were recently developed by our research group. In the current research, N-hydroxysuccinimide (NHS) was added to the cross-linking reaction to enable a decrease in the EDC content and therefore also the cytotoxicity, without decreasing the bonding strength. The antibiotic drug clindamycin was added to the bioadhesive formulation. It was selected because of being inert toward the cross-linking reaction. The effects of EDC, NHS, and clindamycin concentrations on the ex vivo bonding strength, drug release profile, and fibroblast viability, as well as the microbial inhibition, were studied. Incorporation of clindamycin was found to improve the bonding strength of the adhesive. Its release profile was highly effective against the two relevant bacterial strains, Staphylococcus albus and Staphylococcus aureus, which were eradicated within less than 48 h. The good cytotoxicity results indicate that our new antibiotic-eluting bioadhesives represent an effective and selective treatment option for bacterial infections. Delivering an antibiotic drug locally using our bioadhesive could decrease the risk of infections and increase the therapeutic effect of the bioadhesive itself.
The manner by which axons distribute synaptic connections along dendrites remains a fundamental unresolved issue in neuronal development and physiology. We found in vitro and in vivo indications that dendrites determine the density, location and strength of their synaptic inputs by controlling the distance of their branches from those of their neighbors. Such control occurs through collective branch convergence, a behavior promoted by AMPA and NMDA glutamate receptor activity. At hubs of convergence sites, the incidence of axo-dendritic contacts as well as clustering levels, pre- and post-synaptic protein content and secretion capacity of synaptic connections are higher than found elsewhere. This coupling between synaptic distribution and the pattern of dendritic overlapping results in ‘Economical Small World Network’, a network configuration that enables single axons to innervate multiple and remote dendrites using short wiring lengths. Thus, activity-mediated regulation of the proximity among dendritic branches serves to pattern and strengthen neuronal connectivity.
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.