Precise measurement of volume of eccrine sweat gland in mental sweating by optical coherence tomography

Optical Review - We have demonstrated dynamic analysis of the physiological function of eccrine sweat glands underneath skin surface by optical coherence tomography (OCT). In this paper, we propose...     

Double bond formation based on nitroaldol reaction and radical elimination: A prototype segment connection method for the total synthesis of nigricanoside A dimethyl ester

During the course of our studies toward the total synthesis of nigricanoside A dimethyl ester, a prototype method for the connection of the left- and right-half segments at the C9′–C10′ double bond was developed using a model system. The method was based on a simple three-step process including: (i) a nitroaldol reaction, (ii) chlorination or thionocarbonylation, and (iii) radical elimination.     

A simple and rapid ultra‐high‐performance liquid chromatography–tandem mass spectrometry method to determine plasma biotin in hemodialysis patients

A simple, rapid, and selective method for determination of plasma biotin was developed using ultra‐high‐performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). After single‐step protein precipitation with methanol, biotin and stable isotope‐labeled biotin as an internal standard (IS) were chromatographed on a pentafluorophenyl stationary‐phase column (2.1 × 100 mm, 2.7 μm) under isocratic conditions using 10 mm ammonium formate–acetonitrile (93:7, v/v) at a flow rate of 0.6 mL/min. The total chromatographic runtime was 5 min for each injection. Detection was performed in a positive electrospray ionization mode by monitoring selected ion transitions at m/z 245.1/227.0 and 249.1/231.0 for biotin and the IS, respectively. The calibration curve was linear in the range of 0.05–2 ng/mL using 300 μL of plasma. The intra‐ and inter‐day precisions were all <7.1%. The accuracy varied from ?0.7 to 8.2%. The developed UHPLC–MS/MS method was successfully applied to determine plasma biotin concentrations in hemodialysis patients. Copyright © 2016 John Wiley & Sons, Ltd.     

Uniform Hölder continuity of approximate solutions to parabolic systems and its application

By means of a minimizing scheme, we constructively define approximate solutions to parabolic systems. On the basis of Campanato theory, these approximate solutions are shown to be locally Hölder equi-continuous with respect to an approximation parameter. As an application, we obtain a weak solution to an initial-boundary value problem with the same Hölder continuity.     

Synthetic Studies on Sialoglycoconjugates 45: Synthesis of 1-Deoxynojirimycin-Containing Oligosaccharides Related to the Cancer-Associated Sialyl-Lewis a Antigen Recognized by Lec-Cams (Selectins)

Abstract

Sialyl-Lewis a (sLe^a), mainly expressed on cancer cells of the digestive organs,² has been known as an important cancer-associated carbohydrate antigen.³ Very recently, it has been demonstrated^4–9 that the (sLe^a) antigen is one of the possible ligands recognized by selectins, a family of lectin-type cell adhesion molecules (LEC-CAMS). These findings suggest that the (sLe^a) antigen may be involved in the process of hematogeneous metastasis of cancer cells. 1-Deoxynojirimycin (DNJ) and related compounds have been shown¹⁰ not only to be potent inhibitors of a-glycosidases and glycoprotein-processing enzymes, but also to be of potential clinical value as antidiabetic, antineoplastic and anti-HIV agents. In a preceding paper we reported the synthesis of DNJ-containing sialyl-Lewis x antigen which has been identified as a major carbohydrate ligand for leukocyte adhesion on vascular endothelium mediated by selectins. The present paper describes the first synthesis of l-deoxynojirimycin- containing cancer-associated (sLe^a) antigen and related compounds.     

Structure Determination and Total Synthesis of (+)‐16‐Hydroxy‐16,22‐dihydroapparicine

Herein, we describe the first asymmetric total synthesis and determination of the relative and absolute stereochemistry of naturally occurring 16‐hydroxy‐16,22‐dihydroapparicine. The key steps include 1) a novel phosphinimine‐mediated cascade reaction to construct the unique 1‐azabicyclo[4.2.2]decane core, including a pseudo‐aminal‐type moiety; 2) a highly stereospecific 1,2‐addition of 2‐acylindole or a methylketone through a Felkin–Anh transition state for the construction of a tetrasubstituted carbon center; and 3) an intramolecular chirality‐transferring Michael reaction of the ketoester, with neighboring‐group participation, to introduce a chiral center at C15 in the target molecule. In addition, we evaluated the antimalarial activity of synthetic (+)‐(15S,16R)‐16‐hydroxy‐16,22‐dihydroapparicine and its intermediate against chloroquine‐resistant Plasmodium falciparum (K1 strain) parasites.     

Transformimidoylation of 1-(N-Alkyliminoformyl) Imidazole with Amino Acid

In our preceeding paper,¹ we described a new synthetic method of reactive 1-(N-alkyliminoformyl)azoles (1) and the transfer of formimidoyl group (transformimidoylation) of 1 with amine, alcohol and the so-called active methylene compounds.     

In vitro gene delivery mediated by lactosylated dendrimer (generation 3, G3)/��-cyclodextrin conjugates into hepatocytes

The purpose of this study is to evaluate in vitro gene delivery efficiency of polyamidoamine (PAMAM) starburst dendrimer (generation 3, G3) conjugates with ??-cyclodextrin (??-CDE (G3)) bearing lactose (Lac-??-CDE) with various degrees of substitution of the lactose moiety (DSL) as a novel hepatocyte-selective carrier. Lac-??-CDE (G3, DSL 1.2) was found to have much higher gene transfer activity than ??-CDE (G3), Lac-??-CDE (G2, DSL 2.6) and Lac-??-CDEs (G3, DSL 2.6, 4.1 and 6.1) in HepG2 cells, which are dependent on the expression of cell-surface asialoglycoprotein receptor (ASGP-R). Lac-??-CDE (G3, DSL 1.2) provided negligible cytotoxicity up to a charge ratio of 100 (carrier/pDNA) in HepG2 cells. These results suggest the potential use of Lac-??-CDE (G3, DSL 1.2) as a non-viral vector for gene delivery toward hepatocytes.     

The first total synthesis of ganglioside GalNAc-GD1a, a target molecule for autoantibodies in Guillain-Barré syndrome

The first synthesis of ganglioside GalNAc-GD1a, featuring efficient glycan assembly and a cyclic glucosyl ceramide as a versatile unit for ganglioside synthesis is described. Although ganglioside GalNAc-GD1a was first found as a brain ganglioside, IgG autoantibodies to GalNAc-GD1a were subsequently found to be closely related to a human peripheral-nerve disorder, Guillain-Barré syndrome, which is the commonest cause of acute flaccid paralysis worldwide. In this study, the characteristic hexasaccharide part carrying two sialic acid residues was synthesized efficiently by use of a readily accessible GM2-core unit as a common unit. The potentially difficult coupling of the oligosaccharide and ceramide moieties was carried out by using a cyclic glucosyl ceramide as a coupling partner for the hexasaccharide part, thereby successfully providing the framework of the target compound. Global deprotection delivered the homogenous ganglioside GalNAc-GD1a. An enzyme-linked immunosorbent assay showed that sera from patients with Guillain-Barré syndrome reacted both with natural and with synthetic GalNAc-GD1a.     

Pathway analysis of super-exchange electronic couplings in electron transfer reactions using a multi-configuration self-consistent field method

We present a novel pathway analysis of super-exchange electronic couplings in electron transfer reactions using localized molecular orbitals from multi-configuration self-consistent field (MCSCF) calculations. In our analysis, the electronic coupling and the tunneling pathways can be calculated in terms of the configuration interaction (CI) Hamiltonian matrix obtained from the localized MCSCF wave function. Making use of the occupation restricted multiple active spaces (ORMAS) method can effectively produce the donor, acceptor, and intermediate configuration state functions (CSFs) and CIs among these CSFs. In order to express the electronic coupling as a sum of individual tunneling pathways contributions, we employed two perturbative methods: L?wdin projection-iteration method and higher-order super-exchange method. We applied them to anion couplings of butane-1,4-diyl and pentane-1,5-diyl. The results were (1) the electronic couplings calculated from the two perturbative methods were in reasonable agreement with those from a non-perturbative method (one-half value of the energy difference between the ground and first excited states), (2) the main tunneling pathways consisted of a small number of lower-order super-exchange pathways where bonding, anti-bonding, or extra-valence-shell orbitals were used once or twice, and (3) the interference among a huge number of higher-order super-exchange pathways significantly contributed to the overall electronic coupling, whereas each of them contributed only fractionally. Our method can adequately take into account both effects of non-dynamical electron correlation and orbital relaxation. Comparing with the analyses based on the Koopmans' theorem (ignoring both effects) and the ORMAS-CIs from frozen localized reference orbitals (ignoring the effect of orbital relaxation), we discuss these effects.