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11.
Liquid-liquid extraction and spectrophotometric determination of palladium with 2-mercaptobenz-amide
2-Mercaptobenzamide (MBA) was investigated as a reagent for the extraction of palladium. The palladium complex of MBA was extracted into tributyl phosphate (TBP). The pKa of the ligand was 5.45 with the stability constant of the palladium complex β2=107.1. The composition of the complex in TBP was Pd:MBA:TBP=1:2:2. Addition of sodium chloride accelerated the rate of extraction. Various interfering ions could be masked with EDTA; Ag(I), Au(III), Os(VIII), Se(IV), Te(IV) etc. interfered. The molar absorptivity was 1.59×104 l mol?1 cm?1; 1–35 μg Pd could be determined at pH 6.0. 相似文献
12.
Noriaki Nagai Mayu Kawaguchi Misa Minami Kana Matsumoto Tatsuji Sasabe Kenji Nobuhara Akira Matsubara 《Molecules (Basel, Switzerland)》2022,27(10)
N,N-diethyl-3-toluamide (DEET) is one of the most widely used insect repellents in the world. It was reported that a solution containing 6–30% cyclodextrin (CD) as a solvent instead of ethanol (EtOH) provided an enhancement of the repellent action time duration of the DEET formulation, although the high-dose CD caused stickiness. In order to overcome this shortcoming, we attempted to prepare a 10% DEET formulation using EtOH containing low-dose CDs (β-CD, 2-hydroxypropyl-β-CD (HPβCD), methyl-β-CD, and sulfobutylether-β-CD) as solvents (DEET/EtOH/CD formulations). We determined the CD concentration to be 0.1% in the DEET/EtOH/CD formulations, since the stickiness of 0.1% CDs was not felt (approximately 8 × 10−3 N). The DEET residue on the skin superficial layers was prolonged, and the drug penetration into the skin tissue was decreased by the addition of 0.1% CD. In particular, the retention time and attenuated penetration of DEET on the rat skin treated with the DEET/EtOH/HPβCD formulation was significantly higher in comparison with that of the DEET/EtOH formulation without CD. Moreover, the repellent effect of DEET was more sustained by the addition of 0.1% HPβCD in the study using Aedes albopictus. In conclusion, we found that the DEET/EtOH/HPβCD formulations reduced the skin penetration of DEET and prolonged the repellent action without stickiness. 相似文献
13.
Kana Kobayashi-Taguchi Takashi Saitou Yoshiaki Kamei Akari Murakami Kanako Nishiyama Reina Aoki Erina Kusakabe Haruna Noda Michiko Yamashita Riko Kitazawa Takeshi Imamura Yasutsugu Takada 《Molecules (Basel, Switzerland)》2022,27(10)
Fibroadenomas (FAs) and phyllodes tumors (PTs) are major benign breast tumors, pathologically classified as fibroepithelial tumors. Although the clinical management of PTs differs from FAs, distinction by core needle biopsy diagnoses is still challenging. Here, a combined technique of label-free imaging with multi-photon microscopy and artificial intelligence was applied to detect quantitative signatures that differentiate fibroepithelial lesions. Multi-photon excited autofluorescence and second harmonic generation (SHG) signals were detected in tissue sections. A pixel-wise semantic segmentation method using a deep learning framework was used to separate epithelial and stromal regions automatically. The epithelial to stromal area ratio and the collagen SHG signal strength were investigated for their ability to distinguish fibroepithelial lesions. An image segmentation analysis with a pixel-wise semantic segmentation framework using a deep convolutional neural network showed the accurate separation of epithelial and stromal regions. A further investigation, to determine if scoring the epithelial to stromal area ratio and the SHG signal strength within the stromal area could be a marker for differentiating fibroepithelial tumors, showed accurate classification. Therefore, molecular and morphological changes, detected through the assistance of computational and label-free multi-photon imaging techniques, enable us to propose quantitative signatures for epithelial and stromal alterations in breast tissues. 相似文献
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Fumiko Fujisaki Sachi Hiromatsu Yumiko Matsumura Aki Fukami Nobuhiro Kashige Fumio Miake Kunihiro Sumoto 《Journal of heterocyclic chemistry》2013,50(2):417-424
In connection with our studies on antibacterial active compounds in the class of new oxazolidinones against Gram‐positive (Staphylococcus aureus) and Gram‐negative (Escherichia coli) strains, some molecular modifications were attempted. In this study, molecular modifications of 4‐aminomethyloxazolidin‐2‐ones ( 3a ) to the corresponding 4‐acylaminomethyloxazolidin‐2‐one derivatives ( 3c–d ) and preparations of the represented twin‐drug type molecules ( 10–14 ) were investigated. Some additional 4‐dialkylaminomethyloxazolidin‐2‐ones ( 2 ) were also synthesized. The synthesized compounds were evaluated for antibacterial activity with Gram‐positive (S. aureus) and Gram‐negative (E. coli) strains. 相似文献
17.
Strahil Iv. PASTUHOV Naoki HISAMOTO Kunihiro MATSUMOTO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2015,91(3):63-75
Mitogen-activated protein kinase (MAPK) signaling cascades are activated by diverse stimuli such as growth factors, cytokines, neurotransmitters and various types of cellular stress. Our evolving understanding of these signal cascades has been facilitated by genetic analyses and physiological characterization in model organisms such as the nematode Caenorhabditis elegans. Genetic and biochemical studies in C. elegans have shed light on the physiological roles of MAPK cascades in the control of cell fate decision, neuronal function and immunity. Recently it was demonstrated that MAPK signaling is also important for axon regeneration in C. elegans, and the use of C. elegans as a model system has significantly advanced our understanding of the largely conserved molecular mechanisms underlying axon regeneration. This review summarizes our current understanding of the role and regulation of MAPK signaling in C. elegans axon regeneration. 相似文献
18.
Serine‐Selective Aerobic Cleavage of Peptides and a Protein Using a Water‐Soluble Copper–Organoradical Conjugate
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Yohei Seki Dr. Kana Tanabe Dr. Daisuke Sasaki Dr. Youhei Sohma Dr. Kounosuke Oisaki Prof. Dr. Motomu Kanai 《Angewandte Chemie (International ed. in English)》2014,53(25):6501-6505
The site‐specific cleavage of peptide bonds is an important chemical modification of biologically relevant macromolecules. The reaction is not only used for routine structural determination of peptides, but is also a potential artificial modulator of protein function. Realizing the substrate scope beyond the conventional chemical or enzymatic cleavage of peptide bonds is, however, a formidable challenge. Here we report a serine‐selective peptide‐cleavage protocol that proceeds at room temperature and near neutral pH value, through mild aerobic oxidation promoted by a water‐soluble copper–organoradical conjugate. The method is applicable to the site‐selective cleavage of polypeptides that possess various functional groups. Peptides comprising D ‐amino acids or sensitive disulfide pairs are competent substrates. The system is extendable to the site‐selective cleavage of a native protein, ubiquitin, which comprises more than 70 amino acid residues. 相似文献
19.
Kunihiro Ichimura Masatoshi Kidowaki Haruhisa Akiyama Kazuaki Kudo Veronika Strehmel Bernd Strehmel 《Macromolecular rapid communications》1996,17(8):545-551
The surface-assisted alignment of a nematic liquid crystal yields a persistent ordered structure upon cationic photopolymerization of liquid-crystalline epoxides. Linearly polarized light irradiation of a photocrosslinkable polymer containing azobenzene moieties played a crucial role in this procedure since the photoinduced alignment is not deteriorated by heating for polymerization. 相似文献
20.
Dr. Masahiro Ikeshita Sho Furukawa Takahiro Ishikawa Kana Matsudaira Prof.Dr. Yoshitane Imai Prof.Dr. Takashi Tsuno 《ChemistryOpen》2022,11(4)
The Front Cover shows the comparison of circularly polarized luminescence (CPL) properties of square planar platinum(II) complexes with different coordination geometries. Computational studies have revealed that the distortion of the coordination geometry is key to enhancement of the chiroptical responses of these compounds. More information can be found in the Research Article by Masahiro Ikeshita et al. 相似文献