Umpolung Isomerization in Radical Copolymerization of Benzyl Vinyl Ether with Pentafluorophenylacrylate Leading to Degradable AAB Periodic Copolymers.

This study revealed that benzyl vinyl ether (BnVE) shows a peculiar isomerization propagation in its radical copolymerization with an electron-deficient acrylate carrying a pentafluorophenyl group (PFA). The co-monomer pair inherently exhibits the cross-over propagation feature due to the large difference in the electron density. However, the radical species of PFA was found to undergo a backward isomerization to the penultimate BnVE pendant giving a benzyl radical species prior to propagation with BnVE. The isomerization brings a drastic change in the character of the growing radical species from electrophilic to nucleophilic, and thus the isomerized benzyl radial species propagates with PFA. Consequently, the two monomers were consumed in the order AAB (A: PFA; B: BnVE) and the unique periodic consumption was confirmed by the pseudo-reactivity ratios calculated by the penultimate model: r11 =0.174 and r21 =6600 for PFA (M1 ) with BnVE (M2 ). The pentafluorophenyl ester groups of the resulting copolymers are transformed into ester and amide groups by post-polymerization alcoholysis and aminolysis modifications. The unique isomerization in the AAB sequence allowed the periodic introduction of a benzyl ether structure in the backbone leading to efficient degradation under acid conditions.

Neuroprotective Effects of Anti-high Mobility Group Box-1 Monoclonal Antibody Against Methamphetamine-Induced Dopaminergic Neurotoxicity.

High mobility group box-1 (HMGB1) is a ubiquitous non-histone nuclear protein that plays a key role as a transcriptional activator, with its extracellular release provoking inflammation. Inflammatory responses are essential in methamphetamine (METH)-induced acute dopaminergic neurotoxicity. In the present study, we examined the effects of neutralizing anti-HMGB1 monoclonal antibody (mAb) on METH-induced dopaminergic neurotoxicity in mice. BALB/c mice received a single intravenous administration of anti-HMGB1 mAb prior to intraperitoneal injections of METH (4 mg/kg × 2, at 2-h intervals). METH injections induced hyperthermia, an increase in plasma HMGB1 concentration, degeneration of dopaminergic nerve terminals, accumulation of microglia, and extracellular release of neuronal HMGB1 in the striatum. These METH-induced changes were significantly inhibited by intravenous administration of anti-HMGB1 mAb. In contrast, blood-brain barrier disruption occurred by METH injections was not suppressed. Our findings demonstrated the neuroprotective effects of anti-HMGB1 mAb against METH-induced dopaminergic neurotoxicity, suggesting that HMGB1 could play an initially important role in METH toxicity.

Metal-Catalyzed Switching Degradation of Vinyl Polymers via Introduction of an "In-Chain" Carbon-Halogen Bond as the Trigger.

In this work, we achieved switching degradation of vinyl polymers made of a carbon-carbon bonded backbone. Crucial in this strategy was a small feed of methyl α-chloroacrylate (MCA) as the comonomer in radical polymerization of methyl methacrylate (MMA) so that the carbon-halogen bonds were introduced as the triggers for degradation. The "in-chain" trigger was activated by a one-electron redox metal catalyst as the chemical stimulus to generate the carbon-centered radical species, and subsequently, the neighboring carbon-carbon bond was cleaved via an electron transfer of the radical species giving the terminal olefin. Particularly, an iron complex (FeCl2) in conjunction with tributylamine (n-Bu3N) was effective as the chemical stimulus to allow the switching degradation, where the molecular weight was gradually decreased over time. The switching feature was confirmed by some control experiments.

A revisional study of the genus Aulacus Jurine (Hymenoptera: Aulacidae) of Japan.

Japanese species of the genus Aulacus Jurine are revised and seven species are recognized. Two new species, A. davidi sp. n. and A. shizukii sp. n. are described. In addition, A. flavigenis Alekseev and A. sinensis He Chen are newly recorded from the Japanese archipelago. Male genitalia of three species, i.e., A. davidi, A. flavigenis and A. sinensis, are described for the first time. An identification key for Japanese species and DNA barcoding data for A. davidi, A. machaerophorus Kuroda, Kikuchi Konishi and A. sinensis are also provided.

Taxonomic review of the genus Ammophilomima (Diptera: Asilidae: Leptogastrinae) in Japan.

The genus Ammophilomima from Japan is reviewed. No species of this genus have been known from Japan, although a species that is now assigned the name Lobus trimucronatus (Hermann, 1917) was once treated as an Ammophilomima species. In the present study, two new Ammophilomima species are recorded for Japan; i. e. A. amamiensis sp. nov. from Amamioshima Is. and Tokunoshima Is. and A. rikioi sp. nov. from Okinawa Is. Morphological characteristics that distinguish these two Japanese species from other Ammophilomima species and those that separate the Japanese species are presented.

Discovery of the male of a rare aulacid wasp, Pristaulacus emarginaticeps Turner, 1922 (Hymenoptera: Aulacidae) from Vietnam and Laos.

BACKGROUND: Pristaulacus emarginaticeps Turner, 1922 was described from a single female from Hòa Bình Province, Vietnam and it has remained the only recorded specimen. NEW INFORMATION: The male of Pristaulacus emarginaticeps Turner, 1922 is described for the first time and the species is newly recorded from Hà Tinh Province, Vietnam and Houaphanh Province, Laos.