A photocatalyst-free visible-light-mediated solvent-switchable route to stilbenes/vinyl sulfones from ß-nitrostyrenes and arylazo sulfones.

Photocatalyst-free visible-light-mediated reactions, based on the presence of a visible-light-absorbing functional group in the starting material itself in order to exclude the often costly, hazardous, degradable and difficult to remove or recover photoredox catalysts, have been gaining momentum recently. We have employed this approach to develop a denitrative photocatalyst-free visible-light-mediated protocol for the arylation/sulfonylation of ß-nitrostyrenes employing arylazo sulfones (bench-stable photolabile compounds) in a switchable solvent-controlled manner. Arylazo sulfones served as the aryl and sulfonyl radical precursors under blue LED irradiation for the synthesis of trans-stilbenes and (E)-vinyl sulfones in CH3CN and dioxane/H2O 2 : 1, respectively. The absence of any metal, photocatalyst and additive; excellent selectivity (E-stereochemistry) and solvent-switchability; and the use of visible light and ambient temperature are the prime assets of the developed method. Moreover, we report the first photocatalyst-free visible light-driven route to synthesize stilbenes and vinyl sulfones from readily available ß-nitrostyrenes.

Synthesis, characterization and application of chitosan-N-(4-hydroxyphenyl)-methacrylamide derivative as a drug and gene carrier.

The aim of this study was to develop a green method to fabricate a novel CS modified N-(4-hydroxyphenyl)- methacrylamide conjugate (CSNHMA) and to evaluate its biomedical potential. CSNHMA has been prepared by a simple method via aza Michael addition reaction between CS and N- (4-hydroxyphenyl)-methacrylamide (NHMA) in ethanol. Its structural and morphological properties were characterized by various analysis techniques. The obtained results confirmed that a highly porous network structure of CSNHMA was successfully synthesized via aza Michael addition reaction. Consequently, it was analyzed as a drug and gene carrier. CSNHMA/pGL3 showed an enhanced buffering capacity due to the presence of NHMA moiety leading to higher transfection efficiency in all cancer cells (A549, HeLa and HepG2) as compared to native CS and Lipofectamine®. Therefore, these findings clearly support the possibility of using CSNHMA as a good transfection agent. For in vitro drug release study, we prepared CSNHMA nanoparticles (NPs) and curcumin loaded CSNHMA NPs of size <230 nm respectively via the non-toxic ionic gelation route and the encapsulation efficiency of drug was found to be 77.03%. In vitro drug release studies demonstrated a faster and sustained release of curcumin loaded CSNHMA NPs at pH 5.0 compared to physiological pH.

Methyl methacrylate modified chitosan: Synthesis, characterization and application in drug and gene delivery.

A methyl methacrylate (MMA) modified chitosan (CS) conjugate (CSMMA) has been synthesized by a green method via Michael addition reaction between CS and MMA in ethanol. The synthesized conjugate was characterized by FT-IR, 1H NMR, X-ray diffraction spectrometry and SEM analysis. The results confirmed that CS was covalently linked to MMA yielding a highly porous framework. The uses of CSMMA were analyzed as a potential gene and drug delivery agent. CSMMA proved to be a reasonably good gene delivery agent based on transfection efficiency studies in mammalian cancer cell lines (A549, HeLa and HepG2). For drug delivery studies, nanoparticles of the CSMMA biopolymer were prepared by ionic gelation method with sodium tripolyphosphate (TPP). The prepared nanoparticles were characterized in terms of FE-SEM, DLS and zeta potential. In vitro drug release study of curcumin loaded CSMMA nanoparticles showed its maximal entrapment efficiency up to 68% and the drug release was more rapid at a pH (5.0) lower than physiological pH.

Integration of oral health into primary health care: A systematic review.

Integration of oral health into primary health care holds the key to affordable and accessible health care as oral health is still a neglected component in many countries. This review aims to determine integration of oral health into primary health care and provide an evidence-based synthesis on a primary oral healthcare approach. Searches were conducted in various databases like Biomed Central, MEDLINE, Cochrane databases, NCBI (PubMed), Sci-Hub, Google Scholar, and WHO sites. The studies included in this review are according to the following eligibility criteria: the articles in English language, the articles published from January 2000 to October 2018, and only full text article. The search yielded 500 articles. After removal of duplicates: 410 articles screened based on title and abstract, 100 full text articles were assessed for eligibility, and 30 full text articles were included. This review showed evidence how oral health is related to general health: focused on common risk factor approach and bidirectional relationship. There are various ways of integration, such as interprofessional education, interprofessional collaborative practice, closed-loop referral process, and various public and private partnerships, and at the same time, there are a lot of barriers in integration. Thus, the primary oral health care needs to be developed as an integral part of primary health care. Consequently, there is a need to increase finance, health care workforce, government support, and public-private partnership to achieve the goal of affordable and accessible health care, i.e. health for all.