Bottlebrush Polymers for Articular Joint Lubrication: Influence of Anchoring Group Chemistry on Lubrication Properties.

The role of carboxylic, aldehyde, or epoxide groups incorporated into bottlebrush macromolecules as anchoring blocks (or cartilage-binding blocks) is investigated by measuring their lubricating properties and cartilage-binding effectiveness. Mica modified with amine groups is used to mimic the cartilage surface, while bottlebrush polymers functionalized with carboxylic, aldehyde, or epoxide groups played the role of the lubricant interacting with the cartilage surface. We demonstrate that bottlebrushes with anchoring blocks effectively reduce the friction coefficient on modified surfaces by 75-95% compared to unmodified mica.

Development of New Resolvin D1 Analogues for Osteoarthritis Therapy: Acellular and Computational Approaches to Study Their Antioxidant Activities.

In osteoarthritis (OA), oxidative stress plays a crucial role in maintaining and sustaining cartilage degradation. Current OA management requires a combination of pharmaceutical and non-pharmacological strategies, including intraarticular injections of hyaluronic acid (HA). However, several lines of evidence reported that HA oxidation by reactive oxygen species (ROS) is linked with HA cleavage and fragmentation, resulting in reduced HA viscosity.

Oncostatic activities of melatonin: Roles in cell cycle, apoptosis, and autophagy.

Melatonin, the major secretory product of the pineal gland, not only regulates circadian rhythms, mood, and sleep but also has actions in neoplastic processes which are being intensively investigated. Melatonin is a promising molecule which considered a differentiating agent in some cancer cells at both physiological and pharmacological concentrations. It can also reduce invasive and metastatic status through receptors MT1 and MT2 cytosolic binding sites, including calmodulin and quinone reductase II enzyme, and nuclear receptors related to orphan members of the superfamily RZR/ROR.

Chitosan-based biomaterials for the treatment of bone disorders.

Bone is an alive and dynamic organ that is well-differentiated and originated from mesenchymal tissues. Bone undergoes continuous remodeling during the lifetime of an individual. Although knowledge regarding bones and their disorders has been constantly growing, much attention has been devoted to effective treatments that can be used, both from materials and medical performance points of view.

Rational design of smart nano-platforms based on antifouling-nanomaterials toward multifunctional bioanalysis.

The ability to design nanoprobe devices with the capability of quantitative/qualitative operation in complex media will probably underpin the main upcoming progress in healthcare research and development. However, the biomolecules abundances in real samples can considerably alter the interface performance, where unwanted adsorption/adhesion can block signal response and significantly decrease the specificity of the assay. Herein, this review firstly offers a brief outline of several significances of fabricating high-sensitivity and low-background interfaces to adjust various targets' behaviors induced via bioactive molecules on the surface.

Molecular bottlebrush with pH-responsive cleavable bonds as a unimolecular vehicle for anticancer drug delivery.

Drug delivery systems with targeted and smart properties have emerged as an efficient strategy to overcome the challenges of cancer chemotherapy such as toxic side effects and the development of multidrug resistance. In this study, a biocompatible bottlebrush polymer poly((3-(2-bromo-2-methylpropionate)propyldimethylsilyloxy)ethyl methacrylate)-graft-poly(2-methacryloyloxyethyl phosphorylcholine) P(BIBS-EMA)-g-PMPC with pH-responsive silanol cleavable bond was designed and developed for delivery of doxorubicin. A549 cell line of human lung carcinoma was tested.

Were magnetic materials useful in cancer therapy?

Cancer is one of the major challenges fronting the biomedical basic researches in our time. The study and development of effective therapeutic strategies for cancer therapy are vital. Among the many probable core constituents of nanoparticles, magnetite-based nanoparticles have been widely studied for cancer therapy owing to their inherent magnetic features, multifunctional design, biodegradable and biocompatible properties.

Novel Methotrexate-Ciprofloxacin Loaded Alginate-Clay Based Nanocomposite as Anticancer and Antibacterial Co-Drug Delivery System.

In last decades, by increasing multi-drug resistant microbial pathogens an urgent demand was felt in the development of novel antimicrobial agents. Promising nanocomposites composed of clay/alginate/imidazolium-based ionic liquid, have been developed via intercalation of calcium alginate and ionic liquid by ion exchange method. These tailored nanocomposites were used as nanocarriers to simultaneously deliver methotrexate (MTX), and ciprofloxacin (CIP), as anticancer and antibacterial agents, respectively to MCF-7 breast cancer cells.

Antimicrobial bio-nanocomposite films based on gelatin, tragacanth, and zinc oxide nanoparticles - Microstructural, mechanical, thermo-physical, and barrier properties.

Gelatin and tragacanth were employed to fabricate antimicrobial nanocomposites with 1, 3, and 5% zinc oxide nanoparticles (ZnO-NPs). FT-IR and XRD proved new chemical interactions among GEL/TGC/ZnO-NPs and higher crystallinity of nanocomposites, respectively. DSC showed a significant increase in melting point temperature (T) from ~ 90 to ~ 93-101 °C after adding 1-5% ZnO-NPs.

Recent developments in natural and synthetic polymeric drug delivery systems used for the treatment of osteoarthritis.

Osteoarthritis (OA), is a common musculoskeletal disorder that will progressively increase in older populations and is expected to be the most dominant cause of disability in the world population by 2030. The progression of OA is controlled by a multi-factorial pathway that has not been completely elucidated and understood yet. However, over the years, research efforts have provided a significant understanding of some of the processes contributing to the progression of OA.

Para-sulfonatocalix[n]arene-based biomaterials: Recent progress in pharmaceutical and biological applications.

The history, properties, and characteristics of para-sulfonato-calixarenes are described. On the one hand, the inherent antibacterial and antifungal properties against microorganisms, and on the other hand non-toxicity of these supramolecules toward human organs are analyzed. The resulting biocompatibility of para-sulfonato-calixarenes makes them potential candidates for diverse life sciences and pharmaceutical applications without significant side effects.

Overcoming multidrug resistance in cancer: Recent progress in nanotechnology and new horizons.

Multidrug resistance (MDR), defined as the ability of cancer cells to gain resistance to both conventional and novel chemotherapy agents, is an important barrier in treating malignancies. Initially, it was discovered that cellular pumps dependent on ATP were the cause of resistance to chemotherapy, and further studies have found that other mechanisms such as increased metabolism of drugs, decreased drug entry, and defective apoptotic pathways are involved in this process. MDR has been the focus of numerous initiatives and countless studies have been undertaken to better understand MDR and formulate strategies to overcome its effects.

Carbohydrate polymer-based silver nanocomposites: Recent progress in the antimicrobial wound dressings.

Wound healing is a dynamic and complex process which affects the quality of life in patients and annually causes high costs for the health system, worldwide. Polymers from natural origins such as polysaccharides have gained particular interest between researchers for wound dressing applications due to their abundance in nature, biocompatibility with human tissues, and ideal physicochemical properties. Aside from their supportive effect in wound care, polysaccharides and their derivatives can actively contribute to the healing process.

Graphene quantum dot cross-linked carboxymethyl cellulose nanocomposite hydrogel for pH-sensitive oral anticancer drug delivery with potential bioimaging properties.

Herein, graphene quantum dots (GQDs) were introduced as a novel and safe crosslinker for carboxymethyl cellulose to make biodegradable and biocompatible hydrogels. The casting was used as a simple method for the preparation of the CMC/GQDs films. Effects of the GQDs percentage on the physicochemical properties of the films were studied, and several characterizations were performed including Fourier transform infrared spectroscopy, UV-vis spectroscopy, scanning electron microscopy, gas permeability, and mechanical testing analysis.

A novel bioactive quaternized chitosan and its silver-containing nanocomposites as a potent antimicrobial wound dressing: Structural and biological properties.

Wound care is crucial for controlling infections of the injured area. Regarding this, wound dressings with antimicrobial activities are useful to minimize the microbial infections of the wounds. Herein, a series of quaternized chitosan nanocomposite films blended with silver nanoparticles were fabricated with high potential for wound dressing applications.

New potentials for 3-hydroxy-3-methyl-glutaryl-coenzymeA reductase inhibitors: Possible applications in retarding diabetic complications.

The prevalence of diabetes mellitus is increasing all over the world and it is apparent that treatment of diabetic complications has the same importance as primary diabetes treatment and glycemic control. Diabetic complications occur as a result of prolonged hyperglycemia and its consequences, such as advanced glycation end products and reactive oxygen species. Impairment of lipid profile is also contributed to worsening diabetic complications.

Nanocrystalline cellulose: Preparation, physicochemical properties, and applications in drug delivery systems.

Cancer is the leading cause of death all over the world and chemotherapy is an important approach to fight cancer, however, there are many obstacles against successful cancer chemotherapy such as development of multidrug resistance, poor solubility of chemotherapeutic agents and adverse side effects to healthy tissues. An important strategy to overcome these obstacles, is the use of nanotechnology. In recent years, natural polymers such as cellulose and its nanoform structure, nanocrystalline cellulose (NCC), have attracted the interest of researchers in the field of nanotechnology and specially drug delivery systems, due to biocompatibility and biodegradability of NCC.

Polyelectrolyte Carboxymethyl Cellulose for Enhanced Delivery of Doxorubicin in MCF7 Breast Cancer Cells: Toxicological Evaluations in Mice Model.

Purpose: Chemotherapy as an important tool for cancer treatment faces many obstacles such as multidrug resistance and adverse toxic effects on healthy tissues. Drug delivery systems have opened a new window to overcome these problems.

Methods: A polyelectrolyte carboxymethyl cellulose polymer as a magnetic nanocarrier was synthesized for enhancing delivery and uptake of doxorubicin in MCF7 breast cancer cells and decreasing the adverse toxic effects to healthy tissues.

Metformin; an old antidiabetic drug with new potentials in bone disorders.

The prevalence of diabetes mellitus especially type 2 diabetes mellitus is increasing all over the world. In addition to cardiomyopathy and nephropathy, diabetics are at higher risk of mortality and morbidity due to greater risk of bone fractures and skeletal abnormalities. Patients with diabetes mellitus have lower bone quality in comparison to their non-diabetic counterparts mainly because of hyperglycemia, toxic effects of advanced glycosylation end-products (AGEs) on bone tissue, and impaired bone microvascular system.

Multi-branched ionic liquid-chitosan as a smart and biocompatible nano-vehicle for combination chemotherapy with stealth and targeted properties.

A possible approach for clinical cancer treatment is combination chemotherapy. To address this issue, many anticancer agents have been used simultaneously to achieve synergistic effects with the different mechanism of actions, however, their toxic side effects are still a big challenge. In this study, a smart, biocompatible, magnetic nanocarrier composed of multi-branched ionic liquid-chitosan grafted mPEG was designed and used for targeted multidrug delivery of DOX and MTX as model anticancer agents to MCF7 breast cancer cells.

Revealing sub-voxel motions of brain tissue using phase-based amplified MRI (aMRI).

Purpose: Amplified magnetic resonance imaging (aMRI) was recently introduced as a new brain motion detection and visualization method. The original aMRI approach used a video-processing algorithm, Eulerian video magnification (EVM), to amplify cardio-ballistic motion in retrospectively cardiac-gated MRI data. Here, we strive to improve aMRI by incorporating a phase-based motion amplification algorithm.