Design and Characterization of Endostatin-Loaded Nanoparticles for In Vitro Antiangiogenesis in Squamous Cell Carcinoma

The aim of this study is to effectively enhance antitumor activities of endostatin by preparing polymeric nanocarriers. NMR and FT-IR spectra confirmed the successful grafting of the CHT-g-PEI and CHT-g-PEI-PEG-NH2 conjugates. SEM micrographs confirmed the shape of endostatin-loaded nanoparticles to be spherical while both TEM and zeta size results showed nanoparticle’s average size to be 100.6 nm having a positively charged surface with zeta potential of 7.95 mV. The concentrations of CHT and TPP as well as the changing pH conditions account for the increased swelling pattern of endostatin-loaded nanoparticles and influenced endostatin release in vitro. PEI increased the overall amine protonation while PEG aggravated endostatin encapsulation and release. Nanoparticles swell and release endostatin at acidic tumor pH of 6.8 compared to physiological pH of 7.4. The native CHT-g-PEI-PEG-NH2 conjugate showed high cytocompatibility above 80% cell viability across tested formulations. Endostatin-loaded nanoparticles showed a significant reduction in cell viability across tested formulations, with 5.32% cell death at 125 μg/mL and 13.36% at 250 μg/mL following 24 hours’ incubation period. Interestingly, more than a fourfold (61.68%) increment in cytotoxicity was observed at nanoparticle concentration of 1000 μg/mL. It was concluded that CHT-g-PEI-PEG-NH2 is an effective cargo for endostatin delivery with antiangiogenic effect in squamous cell carcinoma

Trends in the Molecular Pathogenesis and Clinical Therapeutics of Common Neurodegenerative Disorders

The term neurodegenerative disorders, encompasses a variety of underlying conditions, sporadic and/or familial and are characterized by the persistent loss of neuronal subtypes. These disorders can disrupt molecular pathways, synapses, neuronal subpopulations and local circuits in specific brain regions, as well as higher-order neural networks. Abnormal network activities may result in a vicious cycle, further impairing the integrity and functions of neurons and synapses, for example, through aberrant excitation or inhibition. The most common neurodegenerative disorders are Alzheimer’s disease, Parkinson’s disease, Amyotrophic Lateral Sclerosis and Huntington’s disease. The molecular features of these disorders have been extensively researched and various unique neurotherapeutic interventions have been developed. However, there is an enormous coercion to integrate the existing knowledge in order to intensify the reliability with which neurodegenerative disorders can be diagnosed and treated. The objective of this review article is therefore to assimilate these disorders’ in terms of their neuropathology, neurogenetics, etiology, trends in pharmacological treatment, clinical management, and the use of innovative neurotherapeutic interventions

Carcinogenic nitrosamines in traditional beer as the cause of oesophageal squamous cell carcinoma in black South Africans

Background. Before the 1930s, squamous cell carcinoma (SCC) of the oesophagus was almost unknown among black South Africans. From the 1930s the annual frequency rose. A dietary cause was sought, the staple diet of black people having changed from sorghum to maize (corn), with traditional beer being brewed from maize. Carcinogenic N-nitrosamines in traditional beer were suggested as a cause of SCC of the oesophagus, with Fusarium moniliforme, a corn saprophyte, thought to play a role. Objectives. To confirm the presence of N-nitrosamines in traditional beer and demonstrate a mechanism for the oncogenesis of oesophageal carcinoma. Methods. Analysis by high-performance liquid chromatography was conducted for the identification of nitrosamines in traditional beer samples, and molecular docking studies were employed to predict the affinity between N-nitrosamines and the S100A2 protein. Results. Carcinogenic N-nitrosamines were identified in all six samples of traditional beer examined (N=18 analyses), and docking studies confirmed a high affinity of the nitrosamine N-nitrosopyrrolidone with the S100A2 protein. This may result in the altered expression of the S100A2 protein, leading to tumour progression and prognosis. Conclusion. It is suggested that carcinogenic N-nitrosamines in traditional beer are a major factor in the causation of SCC of the oesophagus in black South Africans. N-nitrosamines have been shown to produce cancer experimentally, but there has not been conclusive epidemiological evidence that N-nitrosamines are carcinogenic to humans. This study is the first to demonstrate the potential link between N-nitrosamines and a human tumour

A Review on Composite Liposomal Technologies for Specialized Drug Delivery

The combination of liposomes with polymeric scaffolds could revolutionize the current state of drug delivery technology. Although liposomes have been extensively studied as a promising drug delivery model for bioactive compounds, there still remain major drawbacks for widespread pharmaceutical application. Two approaches for overcoming the factors related to the suboptimal efficacy of liposomes in drug delivery have been suggested. The first entails modifying the liposome surface with functional moieties, while the second involves integration of pre-encapsulated drug-loaded liposomes within depot polymeric scaffolds. This attempts to provide ingenious solutions to the limitations of conventional liposomes such as short plasma half-lives, toxicity, stability, and poor control of drug release over prolonged periods. This review delineates the key advances in composite technologies that merge the concepts of depot polymeric scaffolds with liposome technology to overcome the limitations of conventional liposomes for pharmaceutical applications

Poly(ethylene glycol) enclatherated pectin-mucin submicron matrices for intravaginal anti-HIV-1 drug delivery

This paper explores the potential of polyethylene glycol enclatherated pectin-mucin (PEGencl- PEC:MUC) submicron matrices (SMMs) as an intravaginal drug delivery system capable of delivering an anti-HIV-1 agent (zidovudine; AZT) over a prolonged duration. A three factor and three level (33) Box-Behnken statistical design was employed to optimize the SMMs. Optimized PEG-encl-PEC:MUC SMMs prepared as a stable W/O emulsion (determined by the degree of reversible colloidal phenomena) were spherical with a mean particle size of 270.6±5.533nm and mean zeta potential of -34.4±0.539mV. The microencapsulation of AZT and the hydrogen bonding mediated shielding of AZT by SMMs was confirmed by Fourier Transform Infrared (FTIR) analysis. The thermochemical (differential scanning calorimetry and thermogravimetric analysis) data proposed that Ca2+- based macromolecular ionic crosslinking as well as the intermolecular interactions may be responsible for the thermal stability of the delivery system. The partially amorphous nature of drug-loaded SMMs, as confirmed by X-ray diffraction patterns, further strengthened the matricization of AZT into the pectin-mucin matrix. In vitro drug release studies from the SMMs showed approximately 91% zidovudine release in simulated vaginal fluid (SVF) and 94% in phosphate buffered saline (PBS) in 24 hours. The mean dissolution time (MDT) of zidovudine from the SMMs was 5.974 hours. The attainment of required dimensional structure and drug release profiles from SMMs highlights the potential of their inclusion into a secondary carrier system for extended and controlled intravaginal stay.National Research Foundation (NRF) of South Africa.http://www.elsevier.com/locate/ijpharm2017-04-30hb2016Chemistr

Diagnosis and Treatment of Neurological and Ischemic Disorders Employing Carbon Nanotube Technology

Extensive research on carbon nanotubes has been conducted due to their excellent physicochemical properties. Based on their outstanding physicochemical properties, carbon nanotubes have the potential to be employed as theranostic tools for neurological pathologies such as Alzheimer’s disease and Parkinson’s disease including ischemic stroke diagnosis and treatment. Stroke is currently regarded as the third root cause of death and the leading source of immobility around the globe. The development and improvement of efficient and effective procedures for central nervous system disease diagnosis and treatment is necessitated. The main aim of this review is to discuss the application of nanotechnology, specifically carbon nanotubes, to the diagnosis and treatment of neurological disorders with an emphasis on ischemic stroke. Areas covered include the conventional current diagnosis and treatment of neurological disorders, as well as a critical review of the application of carbon nanotubes in the diagnosis and treatment of ischemic stroke, covering areas such as functionalization of carbon nanotubes and carbon nanotube-based biosensors. A broad perspective on carbon nanotube stimuli-responsiveness, carbon nanotube toxicity, and commercially available carbon nanotubes is provided. Potential future studies employing carbon nanotubes have been discussed, evaluating their extent of advancement in the diagnosis and treatment of neurological and ischemic disorders

Dexamethasone-Loaded, PEGylated, vertically aligned, multiwalled carbon nanotubes for potential ischemic stroke intervention

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A Review of the Effect of Processing Variables on the Fabrication of Electrospun Nanofibers for Drug Delivery Applications

Electrospinning is a fast emerging technique for producing ultrafine fibers by utilizing electrostatic repulsive forces. The technique has gathered much attention due to the emergence of nanotechnology that sparked worldwide research interest in nanomaterials for their preparation and application in biomedicine and drug delivery. Electrospinning is a simple, adaptable, cost-effective, and versatile technique for producing nanofibers. For effective and efficient use of the technique, several processing parameters need to be optimized for fabricating polymeric nanofibers. The nanofiber morphology, size, porosity, surface area, and topography can be refined by varying these parameters. Such flexibility and diversity in nanofiber fabrication by electrospinning has broadened the horizons for widespread application of nanofibers in the areas of drug and gene delivery, wound dressing, and tissue engineering. Drug-loaded electrospun nanofibers have been used in implants, transdermal systems, wound dressings, and as devices for aiding the prevention of postsurgical abdominal adhesions and infection. They show great promise for use in drug delivery provided that one can confidently control the processing variables during fabrication. This paper provides a concise incursion into the application of electrospun nanofibers in drug delivery and cites pertinent processing parameters that may influence the performance of the nanofibers when applied to drug delivery