Sunscreens Containing Cyclodextrin Inclusion Complexes for Enhanced Efficiency: A Strategy for Skin Cancer Prevention

Unprotected exposure of skin to solar ultraviolet radiation (UVR) may damage the DNA of skin cells and can lead to skin cancer. Sunscreens are topical formulations used to protect skin against UVR. The active ingredients of sunscreens are UV filters that absorb, scatter, and/or reflect UVR. Preventing the formation of free radicals and repairing DNA damages, natural antioxidants are also added to sunscreens as a second fold of protection against UVR. Antioxidants can help stabilise these formulations during the manufacturing process and upon application on skin. However, UV filters and antioxidants are both susceptible to degradation upon exposure to sunlight and oxygen. Additionally, due to their poor water solubility, natural antioxidants are challenging to formulate and exhibit limited penetration and bioavailability in the site of action (i.e., deeper skin layers). Cyclodextrins (CDs) are cyclic oligosaccharides that are capable of forming inclusion complexes with poorly soluble drugs, such as antioxidants. In this review, we discuss the use of CDs inclusion complexes to enhance the aqueous solubility of antioxidants and chemical UV filters and provide a protective shield against degradative factors. The role of CDs in providing a controlled drug release profile from sunscreens is also discussed. Finally, incorporating CDs inclusion complexes into sunscreens has the potential to increase their efficiency and hence improve their skin cancer prevention.     

Medicinal Plants and Mushrooms with Immunomodulatory and Anticancer Properties—A Review on Hong Kong’s Experience

The immune modulating effects of selected herbs deserve careful studies to gain evidence-based support for their further development. We have been working hard on many items of medicinal herbs to gain insight into their immunomodulatory effects relevant to cancer treatment in particular, while infection control is not excluded. Nine of them have been selected to give the results of our exploration on their biological, particularly immunomodulatory activities. Since Hong Kong people especially favor one medicinal mushroom, viz. Coriolus versicolor, a number of clinical trials using Coriolus for cancer-related studies are included in this review. While immune modulation platforms are being built for relevant studies, a brief account on the research targets and related procedures are given.     

Oscillation criteria for odd‐order nonlinear delay differential equations with a middle term

The oscillation of solutions of the n th‐order delay differential equation was studied in [S. R. Grace and A. Zafer, Math. Meth. Appl. Sci. 2016, 39 1150–1158] when n is even and the n odd case has been referred to as an interesting open problem. In the present work, our primary aim is to address this situation. Our method of the proof that is quite different from the aforementioned study is essentially new. We introduce V _{n ?1}‐type solutions and use comparisons with first‐order oscillatory and second‐order nonoscillatory equations. Examples are given to illustrate the main results. Copyright © 2017 John Wiley & Sons, Ltd.     

On parabolic Kazhdan–Lusztig R-polynomials for the symmetric group

Parabolic R-polynomials were introduced by Deodhar as parabolic analogues of ordinary R-polynomials defined by Kazhdan and Lusztig. In this paper, we are concerned with the computation of parabolic R-polynomials for the symmetric group. Let $S_n$ be the symmetric group on $\{1,2,\dots ,n\}$, and let $S=\{s_i|1\le i\le n?1\}$ be the generating set of $S_n$, where for $1\le i\le n?1$, $s_i$ is the adjacent transposition. For a subset $J?S$, let ${(S_n)}_J$ be the parabolic subgroup generated by J, and let ${(S_n)}^J$ be the set of minimal coset representatives for $S_n/{(S_n)}_J$. For $u\le v\in {(S_n)}^J$ in the Bruhat order and $x\in \{q,?1\}$, let $R_{u,v}^{J,x}(q)$ denote the parabolic R-polynomial indexed by u and v. Brenti found a formula for $R_{u,v}^{J,x}(q)$ when $J=S?\{s_i\}$, and obtained an expression for $R_{u,v}^{J,x}(q)$ when $J=S?\{s_{i?1},s_i\}$. In this paper, we provide a formula for $R_{u,v}^{J,x}(q)$, where $J=S?\{s_{i?2},s_{i?1},s_i\}$ and i appears after $i?1$ in v. It should be noted that the condition that i appears after $i?1$ in v is equivalent to that v is a permutation in ${(S_n)}^{S?\{s_{i?2},s_i\}}$. We also pose a conjecture for $R_{u,v}^{J,x}(q)$, where $J=S?\{s_k,s_{k+1},\dots ,s_i\}$ with $1\le k\le i\le n?1$ and v is a permutation in ${(S_n)}^{S?\{s_k,s_i\}}$.     

Nonoscillatory Solutions of Delay and Neutral Singular Differential Equations

A new nonoscillatory theory is presented for delay and neutral differential equations. In particular our nonlinearity may be singular in both the dependent and independent variables.     

Cooperative engineering as a specific design-based research

In this paper, we first describe what are the main constituents of what we term cooperative engineering, between teachers and researchers, from an epistemological and theoretical viewpoint. We show that this kind of research tries to dilute the ancient dualisms of Western Thought, and we present some features that may contribute to specifying cooperative engineering within the general paradigm of design-based research. In the second part of the paper, we give an empirical account of such a process of engineering at primary school level in mathematics, by focusing on the co-elaboration, between teachers and researchers, of learning sequences at kindergarten (the Treasures Games, situations of graphical representations) and at grade 1 (The Arithmetic and Comprehension at Elementary School program, building of basic numerical capacities). At the end of the paper, we briefly elaborate on what we consider to be major issues relating to cooperative engineering.     

Oscillation criteria for fourth-order functional differential equations

Some new criteria for the oscillation of all solutions of certain fourth-order functional differential equations are established.     

Electrospray ionization mass spectrometry for analysis of low-molecular-weight anticancer drugs and their analogues

In this study, several anticancer drugs and their analogues consisting of organic and organometallic compounds were analyzed by electrospray ionization mass spectrometry (ESI/MS) using a quadrupole mass spectrometer. Protonated molecular ions [M+H]⁺ were observed for all of the compounds studied, and in the case of the two steroid sulfates, deprotonated molecular ions [M-H]^? were obtained. Tandem mass spectrometry was performed on these quasimolecular ions, and the product ions formed provided useful fragmentation patterns that were characteristic for the compounds. This study provides evidence that ESI/MS is a sensitive technique for structure confirmation and identification of small organic and organometallic molecules.     

Elucidating the Glucokinase Activating Potentials of Naturally Occurring Prenylated Flavonoids: An Explicit Computational Approach

Glucokinase activators are considered as new therapeutic arsenals that bind to the allosteric activator sites of glucokinase enzymes, thereby maximizing its catalytic rate and increasing its affinity to glucose. This study was designed to identify potent glucokinase activators from prenylated flavonoids isolated from medicinal plants using molecular docking, molecular dynamics simulation, density functional theory, and ADMET analysis. Virtual screening was carried out on glucokinase enzymes using 221 naturally occurring prenylated flavonoids, followed by molecular dynamics simulation (100 ns), density functional theory (B3LYP model), and ADMET (admeSar 2 online server) studies. The result obtained from the virtual screening with the glucokinase revealed arcommunol B (−10.1 kcal/mol), kuwanon S (−9.6 kcal/mol), manuifolin H (−9.5 kcal/mol), and kuwanon F (−9.4 kcal/mol) as the top-ranked molecules. Additionally, the molecular dynamics simulation and MM/GBSA calculations showed that the hit molecules were stable at the active site of the glucokinase enzyme. Furthermore, the DFT and ADMET studies revealed the hit molecules as potential glucokinase activators and drug-like candidates. Our findings suggested further evaluation of the top-ranked prenylated flavonoids for their in vitro and in vivo glucokinase activating potentials.