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This paper provides the classification of the review texts on a smartphone application posted on social media. We propose a high performance binary classification method (positive/negative) of review texts, which uses the bidirectional long short-term memory (biLSTM) self-attentional Transformer and is based on the distributed representations created by unsupervised learning of a manually labelled small review corpus, dictionary, and an unlabeled large review corpus. The proposed method obtained higher accuracy as compared to the existing methods, such as StarSpace or the Bidirectional Encoder Representations from Transformer (BERT).

The oxidative cyclization of β-substituted β,γ-unsaturated carboxylic acids using a hypervalent iodine reagent to provide 4-substituted furan-2-one products, is reported. In this cyclization, the use of a highly electrophilic PhI(OTf)2, which is in situ prepared from PhI(OAc)2 and Me3SiOTf, is crucial. Depending on the substitution pattern at the α-position of the substrates, furan-2(5H)-ones or furan-2(3H)-ones are produced. Thus, the present method offers a useful tool for accessing various types of 4-substituted furan-2-ones that are important structural motifs in the field of organic chemistry and medicinal chemistry.

A new class of hypervalent iodine reagents containing phthalimidate was synthesized, and structurally characterized by X-ray analysis. The benziodoxole-based reagent displays satisfactory solubility in common organic solvents and is reasonably stable in solution as well as in the solid state. The reagent was used for the oxidative amination of the C(sp(3))-H bond of N,N-dimethylanilines. In addition, the reagent was also applicable to oxidative amination with rearrangement of trialkylamines as well as enamines that were prepared in situ from secondary amines and aldehydes.

The iodine-catalyzed decarboxylative amidation of β,γ-unsaturated carboxylic acids with chloramine salts is described. This method enables the regioselective synthesis of allylic amides from various types of β,γ-unsaturated carboxylic acids containing substituents at the α- and β-positions. In the reaction, N-iodo-N-chloroamides, generated by the reaction of a chloramine salt with I2 , function as a key active species. The reaction provides an attractive alternative to existing methods for the synthesis of useful secondary allylic amine derivatives.

The authors investigated the bond properties of large-diameter PVA fibers, as well as the relationship between the tensile behavior of fiber-reinforced concrete (FRC) and the bond properties of fibers. Dumbbell-shaped specimens with a cross-sectional size of 30 by 30 mm were fabricated using FRC with 2.0% by volume of PVA fibers 0.66 mm in diameter and 30 or 20 mm in length and were subjected to tension tests. Bond tests on the PVA fibers were also conducted using dumbbell-shaped specimens with a separator in the center by changing the embedment length and angle of the fibers. Under the conditions of the bond tests, the fracture loads of a single fiber were approximately 100 N. The values remained nearly constant even when the embedment angles varied between 0° and 75°. The post-cracking maximum load on dumbbell-shaped specimens divided by the number of fibers observed on each fracture surface (30 by 30 mm) ranged between 80 and 100 N, which were similar to the fracture loads per fiber obtained from the bond tests.

α-Tertiary amines (ATAs) are attractive structural motifs that are frequently found in biologically active molecules. Therefore, the development of an efficient method for the synthesis of ATAs represents an important research topic in the field of medicinal chemistry as well as organic chemistry. Although the Ritter reaction is a reliable approach for preparing α-tertiary amine derivatives via intermolecular amination reactions, the typical methods suffer from disadvantages such as harsh reaction conditions and the use of strong acids. Because of this, it has been of limited use in the synthesis of ATAs. We report here on the decarboxylative Ritter-type amination of carboxylic acids bearing an α-quaternary carbon center using a combination of PhI(OAc)2 and molecular iodine (I2) to produce the corresponding α-tertiary amine derivatives. This reaction proceeded at ambient temperature on the benchtop with a fluorescent light. Mechanistic investigations suggest that the reaction proceeds via the formation of...

Metabolic disorders including obesity and insulin resistance have their basis in dysregulated lipid metabolism and low-grade inflammation. In a microarray search of unique lipase-related genes whose expressions are associated with obesity, we found that two secreted phospholipase A2s (sPLA2s), PLA2G5 and PLA2G2E, were robustly induced in adipocytes of obese mice. Analyses of Pla2g5−/− and Pla2g2e−/− mice revealed distinct and previously unrecognized roles of these sPLA2s in diet-induced obesity. PLA2G5 hydrolyzed phosphatidylcholine in fat-overladen low-density lipoprotein to release unsaturated fatty acids, which prevented palmitate-induced M1 macrophage polarization. As such, PLA2G5 tipped the immune balance toward an M2 state, thereby counteracting adipose tissue inflammation, insulin resistance, hyperlipidemia and obesiy. PLA2G2E altered minor lipoprotein phospholipids, phosphatidylserine and phosphatidylethanolamine, and moderately facilitated lipid accumulation in adipose tissue and liver. Collectively, the identification of “metabolic sPLA2s” adds this gene family to a growing list of lipolytic enzymes that act as metabolic coordinators.

Microenvironment-based alterations in phenotypes of mast cells influence the susceptibility to anaphylaxis, yet the mechanisms underlying proper maturation of mast cells toward an anaphylaxis-sensitive phenotype are incompletely understood. Here we report that PLA2G3, a mammalian homolog of anaphylactic bee venom phospholipase A2, regulates this process. PLA2G3 secreted from mast cells is coupled with fibroblastic lipocalin-type PGD2 synthase (L-PGDS) to provide PGD2, which facilitates mast-cell maturation via PGD2 receptor DP1. Mice lacking PLA2G3, L-PGDS or DP1, mast cell–deficient mice reconstituted with PLA2G3-null or DP1-null mast cells, or mast cells cultured with L-PGDS–ablated fibroblasts exhibited impaired maturation and anaphylaxis of mast cells. Thus, we describe a lipid-driven PLA2G3–L-PGDS–DP1 loop that drives mast cell maturation.

A new class of hypervalent iodine reagents containing phthalimidate was synthesized, and structurally characterized by X-ray analysis. The benziodoxole-based reagent displays satisfactory solubility in common organic solvents and is reasonably stable in solution as well as in the solid state. The reagent was used for the oxidative amination of the C(sp3)H bond of N,N-dimethylanilines. In addition, the reagent was also applicable to oxidative amination with rearrangement of trialkylamines as well as enamines that were prepared in situ from secondary amines and aldehydes.

The metal-free economical approach offers access to various aryl-, hetaryl- and alkyl-substituted secondary allylic amide derivatives, such as sulfonyl amides and carbamates.

Anti-mannotriose (Man3) antibodies were previously isolated from a Keio phage library displaying human single chain variable fragments (scFvs) using a neoglycolipid, Man3- dipalmitoylphosphatidylethanolamine. Of three genes constructed, the 5A3 clone was expressed in mouse myeloma NS0 cells as a conjugate with human IgG1 Fc (scFv-Fc) and characterized (Sakai, K., Shimizu, Y., Chiba, T., Matsumoto-Takasaki, A., Kusada, Y., Zhang, W., Nakata, M., Kojima, N., Toma, K., Takayanagi, A., Shimizu, N., and Fujita-Yamaguchi, Y. (2007) Biochemistry 46, 253–262; Zhang, W., Matsumoto-Takasaki, A., Kusada, Y., Sakaue, H., Sakai, K., Nakata, M., and Fujita-Yamaguchi, Y. (2007) Biochemistry 46, 263–270). Similarly, anti-Lex phages were screened from the same library with lacto-N-fucopentaose III (LNFPIII; Lex)-dipalmitoylphosphatidylethanolamine. Of five phage clones isolated, two scFv genes were constructed to express scFv-Fc proteins in NS0 cells. As was experienced with anti-Man3 scFv-Fc clones, only one anti-LNFPIII clone, 1F12, was successfully produced and purified as an scFv-Fc protein. Although anti-LNFPIII 1F12 and anti-Man3 5A3 scFv-Fc proteins were secreted into media, a decline in scFv-Fc production was observed with both stable clones during early passages. Transient expression of anti-LNFPIII and anti-Man3 scFv-Fc genes in COS-7 cells and subsequent analyses of scFv-Fc protein expression revealed accumulation of translated proteins in the endoplasmic reticulum for scFv-Fc proteins derived from clones that did not survive as stable clones. This report describes the following: (i) isolation of anti-LNFPIII scFv genes; (ii) purification of anti-LNFPIII scFv-Fc proteins from stably and transiently expressed cells; and (iii) extracellular or intracellular localization of two anti-LNFPIII and three anti-Man3 scFv-Fc proteins. The results suggest that expression of anti-Man3 and other anti-carbohydrate antibodies in mammalian cells is disadvantageous for cell growth.

A novel oxidative decarboxylation of β,γ-unsaturated carboxylic acids mediated by hypervalent iodine(III) reagents is described. The decarboxylative C–O bond forming reaction proceeded in the presence of PhI(OAc)2 to give the corresponding allylic acetates. In addition, decarboxylative C–N bond formation was achieved by utilizing hypervalent iodine(III) reagents containing an I–N bond. Mechanistic studies suggest the unique reactivity of hypervalent iodine reagents in this ionic oxidative decarboxylation.

A novel oxidative decarboxylation of β,γ-unsaturated carboxylic acids mediated by hypervalent iodine(III) reagents is described. The decarboxylative C–O bond forming reaction proceeded in the presence of PhI(OAc)2 to give the corresponding allylic acetates. In addition, decarboxylative C–N bond formation was achieved by utilizing hypervalent iodine(III) reagents containing an I–N bond. Mechanistic studies suggest the unique reactivity of hypervalent iodine reagents in this ionic oxidative decarboxylation.

A timed-release derivative of mitomycin C (MMC), agarose bead conjugate (MMC-AB), was synthesized using cyanogen bromide method. MMC was released successively for considerably longer period from MMC-AB in vitro and in vivo after intraperitoneal injection to mice. MMC-AB exhibited almost identical inhibitory effect against growth of Ehrlich ascites carcinoma (EAC) cells to free MMC and less toxicity to ddY mouse than free MMC. Calculated therapeutic index (LD10/ED90) of MMC-AB was two times greater than that of free MMC, suggesting its advantage in cancer chemotherapy. On the life span of EAC bearing ddY mouse, MMC-AB showed almost similar efficiency with that of free MMC but less activity was exhibited against BDF1 mouse transplanted L1210 leukemia.

A new derivative of mitomycin C, mitomycin C-agarose bead conjugate, was synthesized by using cyanogen bromide method. Biologically active mitomycin C was released successively from the conjugate with a half-life of about 6 day in vitro, and also in vivo following subcutaneous injection of conjugate.

The regeneration characteristics and biological activities of mitomycin C-dextran conjugate (MMC-D) were investigated in comparison with those of free mitomycin C (MMC), and the following results were obtained. (1) MMC is coupled at the 1a-nitrogen position via an amide linkage to a carboxyl group of e-aminocaproic acid (6-aminohexanoic acid) which was introduced onto dextran as a spacer. (2) MMC-D was stabler than MMC against acid-catalyzed and metabolic degradation. (3) MMC was liberated from MMC-D with a half-life of about 24 h under physiological conditions (pH 7.4, 37°C) and more rapidly at higher pH. (4) Liver homogenate did not accelerate the liberation of MMC from MMC-D. (5) Antimicrobial activity of MMC-D against Escherichia coli B was less than one-eighteenth of that of MMC. (6) MMC-D showed about one-tenth of the antitumor activity of MMC in vitro in contact with L1210 leukemia cells, but showed almost equal efficiency in the i. p.-i. p. system in vivo, suggesting that MMC-D exhibited activity after being regenerated to the parent drug in the body.