Blessing A. Aderibigbe

Bio: Blessing A. Aderibigbe is an academic researcher from University of Fort Hare. The author has contributed to research in topics: Drug delivery & Medicine. The author has an hindex of 20, co-authored 93 publications receiving 1367 citations. Previous affiliations of Blessing A. Aderibigbe include University of the Witwatersrand & Tshwane University of Technology.

Alginate in Wound Dressings

Abstract: Alginate is a biopolymer used in a variety of biomedical applications due to its favourable properties, such as biocompatibility and non-toxicity. It has been particularly attractive in wound healing applications to date. It can be tailored to materials with properties suitable for wound healing. Alginate has been used to prepare different forms of materials for wound dressings, such as hydrogels, films, wafers, foams, nanofibres, and in topical formulations. The wound dressings prepared from alginate are able to absorb excess wound fluid, maintain a physiologically moist environment, and minimize bacterial infections at the wound site. The therapeutic efficacy of these wound dressings is influenced by the ratio of other polymers used in combination with alginate, the nature of cross linkers used, the time of crosslinking, nature of excipients used, the incorporation of nanoparticles, and antibacterial agents. This review provides a comprehensive overview of the different forms of wound dressings containing alginate, in vitro, and in vivo results.

Metal-Based Nanoparticles for the Treatment of Infectious Diseases

Abstract: Infectious diseases can be transmitted and they cause a significant burden on public health globally. They are the greatest world killers and it is estimated that they are responsible for the demise of over 17 million people annually. The impact of these diseases is greater in the developing countries. People with compromised immune systems and children are the most affected. Infectious diseases may be caused by bacteria, viruses, and protozoa. The treatment of infectious diseases is hampered by simultaneous resistance to multiple drugs, indicating that there is a serious and pressing need to develop new therapeutics that can overcome drug resistance. This review will focus on the recent reports of metal-based nanoparticles that are potential therapeutics for the treatment of infectious diseases and their biological efficacy (in vitro and in vivo).

Cinnamic Acid Derivatives and Their Biological Efficacy.

Abstract: The role played by cinnamic acid derivatives in treating cancer, bacterial infections, diabetes and neurological disorders, among many, has been reported. Cinnamic acid is obtained from cinnamon bark. Its structure is composed of a benzene ring, an alkene double bond and an acrylic acid functional group making it possible to modify the aforementioned functionalities with a variety of compounds resulting in bioactive agents with enhanced efficacy. The nature of the substituents incorporated into cinnamic acid has been found to play a huge role in either enhancing or decreasing the biological efficacy of the synthesized cinnamic acid derivatives. Some of the derivatives have been reported to be more effective when compared to the standard drugs used to treat chronic or infectious diseases in vitro, thus making them very promising therapeutic agents. Compound 20 displayed potent anti-TB activity, compound 27 exhibited significant antibacterial activity on S. aureus strain of bacteria and compounds with potent antimalarial activity are 35a, 35g, 35i, 36i, and 36b. Furthermore, compounds 43d, 44o, 55g-55p, 59e, 59g displayed potent anticancer activity and compounds 86f-h were active against both hAChE and hBuChE. This review will expound on the recent advances on cinnamic acid derivatives and their biological efficacy.

Chitosan and Cellulose-Based Hydrogels for Wound Management.

Abstract: Wound management remains a challenge worldwide, although there are several developed wound dressing materials for the management of acute and chronic wounds. The wound dressings that are currently used include hydrogels, films, wafers, nanofibers, foams, topical formulations, transdermal patches, sponges, and bandages. Hydrogels exhibit unique features which make them suitable wound dressings such as providing a moist environment for wound healing, exhibiting high moisture content, or creating a barrier against bacterial infections, and are suitable for the management of exuding and granulating wounds. Biopolymers have been utilized for their development due to their non-toxic, biodegradable, and biocompatible properties. Hydrogels have been prepared from biopolymers such as cellulose and chitosan by crosslinking with selected synthetic polymers resulting in improved mechanical, biological, and physicochemical properties. They were useful by accelerating wound re-epithelialization and also mimic skin structure, inducing skin regeneration. Loading antibacterial agents into them prevented bacterial invasion of wounds. This review article is focused on hydrogels formulated from two biopolymers—chitosan and cellulose—for improved wound management.

Quinoline-Based Hybrid Compounds with Antimalarial Activity

Abstract: The application of quinoline-based compounds for the treatment of malaria infections is hampered by drug resistance. Drug resistance has led to the combination of quinolines with other classes of antimalarials resulting in enhanced therapeutic outcomes. However, the combination of antimalarials is limited by drug-drug interactions. In order to overcome the aforementioned factors, several researchers have reported hybrid compounds prepared by reacting quinoline-based compounds with other compounds via selected functionalities. This review will focus on the currently reported quinoline-based hybrid compounds and their preclinical studies.

Metal-based nanoparticles as antimicrobial agents: an overview.

Abstract: Metal-based nanoparticles have been extensively investigated for a set of biomedical applications. According to the World Health Organization, in addition to their reduced size and selectivity for bacteria, metal-based nanoparticles have also proved to be effective against pathogens listed as a priority. Metal-based nanoparticles are known to have non-specific bacterial toxicity mechanisms (they do not bind to a specific receptor in the bacterial cell) which not only makes the development of resistance by bacteria difficult, but also broadens the spectrum of antibacterial activity. As a result, a large majority of metal-based nanoparticles efficacy studies performed so far have shown promising results in both Gram-positive and Gram-negative bacteria. The aim of this review has been a comprehensive discussion of the state of the art on the use of the most relevant types of metal nanoparticles employed as antimicrobial agents. A special emphasis to silver nanoparticles is given, while others (e.g., gold, zinc oxide, copper, and copper oxide nanoparticles) commonly used in antibiotherapy are also reviewed. The novelty of this review relies on the comparative discussion of the different types of metal nanoparticles, their production methods, physicochemical characterization, and pharmacokinetics together with the toxicological risk encountered with the use of different types of nanoparticles as antimicrobial agents. Their added-value in the development of alternative, more effective antibiotics against multi-resistant Gram-negative bacteria has been highlighted.

Stent Thrombogenicity Early in High Risk Interventional Settings is Driven by Stent Design and Deployment, and Protected by Polymer-Drug Coatings

Abstract: Background—Stent thrombosis is a lethal complication of endovascular intervention. Concern has been raised about the inherent risk associated with specific stent designs and drug-eluting coatings, yet clinical and animal support is equivocal. Methods and Results—We examined whether drug-eluting coatings are inherently thrombogenic and if the response to these materials was determined to a greater degree by stent design and deployment with custom-built stents. Drug/polymer coatings uniformly reduce rather than increase thrombogenicity relative to matched bare metal counterparts (0.65-fold; P=0.011). Thick-strutted (162 μm) stents were 1.5-fold more thrombogenic than otherwise identical thin-strutted (81 μm) devices in ex vivo flow loops (P<0.001), commensurate with 1.6-fold greater thrombus coverage 3 days after implantation in porcine coronary arteries (P=0.004). When bare metal stents were deployed in malapposed or overlapping configurations, thrombogenicity increased compared with apposed, length-matche...

Nano-Strategies to Fight Multidrug Resistant Bacteria-"A Battle of the Titans".

Abstract: Infectious diseases remain one of the leading causes of morbidity and mortality worldwide. The WHO and CDC have expressed serious concern regarding the continued increase in the development of multidrug resistance among bacteria. Therefore, the antibiotic resistance crisis is one of the most pressing issues in global public health. Associated with the rise in antibiotic resistance is the lack of new antimicrobials. This has triggered initiatives worldwide to develop novel and more effective antimicrobial compounds as well as to develop novel delivery and targeting strategies. Bacteria have developed many ways by which they become resistant to antimicrobials. Among those are enzyme inactivation, decreased cell permeability, target protection, target overproduction, altered target site/enzyme, increased efflux due to over-expression of efflux pumps, among others. Other more complex phenotypes, such as biofilm formation and quorum sensing do not appear as a result of the exposure of bacteria to antibiotics although, it is known that biofilm formation can be induced by antibiotics. These phenotypes are related to tolerance to antibiotics in bacteria. Different strategies, such as the use of nanostructured materials, are being developed to overcome these and other types of resistance. Nanostructured materials can be used to convey antimicrobials, to assist in the delivery of novel drugs or ultimately, possess antimicrobial activity by themselves. Additionally, nanoparticles (e.g., metallic, organic, carbon nanotubes, etc.) may circumvent drug resistance mechanisms in bacteria and, associated with their antimicrobial potential, inhibit biofilm formation or other important processes. Other strategies, including the combined use of plant-based antimicrobials and nanoparticles to overcome toxicity issues, are also being investigated. Coupling nanoparticles and natural-based antimicrobials (or other repurposed compounds) to inhibit the activity of bacterial efflux pumps; formation of biofilms; interference of quorum sensing; and possibly plasmid curing, are just some of the strategies to combat multidrug resistant bacteria. However, the use of nanoparticles still presents a challenge to therapy and much more research is needed in order to overcome this. In this review, we will summarize the current research on nanoparticles and other nanomaterials and how these are or can be applied in the future to fight multidrug resistant bacteria.