Participation of lipid peroxidation in rat pertussis vaccine pleurisy. III. Thiobarbituric acid (TBA) reactant and lysosomal enzyme

Activity of lysosomal enzymes, such as N-acetyl-beta-D-glucosaminidase (NAG), was assayed in exudate on a rat model of Bordetella pertussis vaccine pleurisy. Thiobarbituric acid (TBA)-reactive substances (TBA.R) and superoxide dismutase (SOD) activity were then monitored in the exudate on the acute phase response in this inflammatory model. Retention of the exudate in the pleural space increased rapidly after the challenge, and the exudate volume at 24 h reached about three times the volume at 6 h. The activity of SOD at 6 h was shown to be higher than that at 24 h after the challenge, thus showing negative correlations with TBA-R levels and exudate volume. The levels of TBA.R rapidly increased and reached maximum values at 24 h. It was concluded that the above three parameters correlated to the acute phase response in this inflammatory model.     

Carbazoledioxazines having long alkyl groups. 2. Synthesis of carbazoledioxazines with angular type structure

Carbazoledioxazines with an angular type structure (5,15-dialkyl-7,17-dialkyloxy-9,19-dichloro-5,15-dihydrodiindolo[2,3-c:2′,3′-n]triphenodioxazines) were selectively synthesized by electrochemical oxidative ring closure of precursors (2,5-bis(9-alkyl-2-alkyloxy-3-carbazolylamino)-3,6-dichloro-1,4-benzoquinones). The structure was confirmed by ¹H-nmr and other instrumental analyses. Their thermal properties and solubilities were investigated and were compared with those of carbazoledioxazines with a linear type structure.     

Spectroscopic Properties of Amine‐substituted Analogues of Firefly Luciferin and Oxyluciferin

Spectroscopic and photophysical properties of firefly luciferin and oxyluciferin analogues with an amine substituent (NH₂, NHMe and NMe₂) at the C6' position were studied based on absorption and fluorescence measurements. Their π‐electronic properties were investigated by DFT and TD‐DFT calculations. These compounds showed fluorescence solvatochromism with good quantum yields. An increase in the electron‐donating strength of the substituent led to the bathochromic shift of the fluorescence maximum. The fluorescence maxima of the luciferin analogues and the corresponding oxyluciferin analogues in a solvent were well correlated with each other. Based on the obtained data, the polarity of a luciferase active site was explained. As a result, the maximum wavelength of bioluminescence for a luciferin analogue was readily predicted by measuring the photoluminescence of the luciferin analogue in place of that of the corresponding oxyluciferin analogue.     

Numerical analysis of the behavior of hydrogen added into a free-burning arc

The objective of the present work is to investigate the behavior of hydrogen in an atmospheric-pressure free-burning argon are when a small amount of hydrogen is added into the arc. A two-dimensional model calculation is carried out under the assumption that the ionization reaction of argon is in equilibrium and the reactions among hydrogen molecules, atoms, ions, and electrons are not necessarily in equilibrium. This calculation gives the following conclusion. The hydrogen mass fraction of 0.001 is too small to affect the flow and temperature fields markedly, and the concentration ratios among the hydrogen species are in equilibrium in the greater part of the arc region except for same parts with a steep temperature gradient. The hydrogen mass Junction, however, is not uniform in the me and, especially in the high-temperature region near the cathodes, over three dynes mass fraction of the hydrogen accumulates and flows downstream to cause a high flux of hydrogen atom toward the anode. This phenomena can be explained by the large difference between the diffusivity of hydrogen atom and that of hydrogen ion in argon ion.     

Separation and Transport of Lithium of 10-5 M in the Presence of Sodium Chloride Higher than 0.1 M

Lithium is an important element for lithium battery and clinical treatment of manic depression. Thus,rapid and accurate methods for the determination of lithium and its separation and collection of lithium in recycle are receiving a great concern. Because of the high concentrations of Na⁺ in sea water and blood, very high Li⁺/Na⁺ selectivity is required for the separation and determination of Li⁺ at concentration less than 10^-4 M (700 ppb) in a large excess of Na⁺. We report here the methods of separation, transport and determination of lithium as low as 10^-5 M (M=mol dm^-3) in the presence of Na⁺ more than 0.1 M by using a water-soluble octabromoporphyrin; H₂P^4-) synthesized in our laboratory.     

Reactions of sterically protected phosphaalkenes with some boron reagents

The reactions of sterically protected phosphaalkenes with some boron reagents, such as boron hydrides, were carried out leading to hydroboration products depending on the substrates and boron reagents. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 187–196, 1999     

Synthesis and photophysical properties of azuleno[1′,2′:4,5]pyrrolo[2,1-b]quinazoline-6,14-diones: Azulene analogs of tryptanthrin

Azulene analog of tryptanthrin, azuleno[1′,2′:4,5]pyrrolo[2,1-b]quinazoline-6,14-dione, was successfully prepared by the condensation reaction of azuleno[2,1-b]pyrrole-2,3-dione with isatoic anhydride in the presence of sodium hydride or diisopropylethylamine (DIPEA). Its 2-halo derivatives were also obtained in high yields by the condensation reaction with 5-haloisatoic anhydrides in the presence of DIPEA. Reactivity toward electrophilic reagents was revealed by halogenation with N-bromosuccinimide (NBS) or N-iodosuccinimide (NIS) to afford 12-halo derivatives in high yields. Among the halo derivatives, 2-iodo and 12-iodo derivatives were reactive enough to afford phenylethynyl derivatives under Pd-catalyzed Sonogashira cross-coupling conditions. Within the phenylethynyl derivatives, only 12-phenylethynyl derivative was transformed into its 1,1,4,4-tetracyanobutadiene (TCBD) derivative by the reaction with TCNE. Amphoteric redox properties of the novel azulene analogs of tryptanthrin were characterized by spectroscopic and voltammetric analyses.     

DNA Origami Scaffolds as Templates for Functional Tetrameric Kir3 K+ Channels

In native systems, scaffolding proteins play important roles in assembling proteins into complexes to transduce signals. This concept is yet to be applied to the assembly of functional transmembrane protein complexes in artificial systems. To address this issue, DNA origami has the potential to serve as scaffolds that arrange proteins at specific positions in complexes. Herein, we report that Kir3 K⁺ channel proteins are assembled through zinc‐finger protein (ZFP)‐adaptors at specific locations on DNA origami scaffolds. Specific binding of the ZFP‐fused Kir3 channels and ZFP‐based adaptors on DNA origami were confirmed by atomic force microscopy and gel electrophoresis. Furthermore, the DNA origami with ZFP binding sites nearly tripled the K⁺ channel current activity elicited by heterotetrameric Kir3 channels in HEK293T cells. Thus, our method provides a useful template to control the oligomerization states of membrane protein complexes in vitro and in living cells.     

Synthesis and physiological activity of novel tocopheryl glycosides

Vitamin E glycosides were synthesized and enzymatic hydrolysis was examined for use as potential pro-drugs, however, the glycoside bond was found to be stable. On the other hand, among the glycosides synthesized, dl-alpha-tocopherylglucoside (6b) and dl-alpha-tocopherylmannoside (6c) showed strong inhibitory action on histamine release from mast cells. In addition, 6c also showed a suppressive action on IgE antibody formation. Thus, tocopheryl glycoside showed new properties compared to tocopherol (vitamin E). In particular, 6c was shown to be a novel lead compound with excellent manifold anti-allergic activity and anti-inflammatory activity.