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121.
Careful base and solvent optimization for catalytic amination is described. A Pd-catalyzed amination between some arylbromide and unprotected piperazine (1 equiv) was efficiently carried out with Pd/BINAP catalyst in a toluene–DBU solvent system, which is useful for the one-pot preparation of unsymmetrical piperazine through amination and in-situ N-protection. Reaction with N-BOC-piperazine was also successful in toluene–DBU or more polar NMP with Cs2CO3 as a key base. No reports have previously reported such solvent and base optimization in arylpiperazine synthesis.  相似文献   
122.
Larvae of bigmouth manefish Caristius macropus are described and illustrated on the basis of seven specimens (4.2–10.5 mm in body length) from the Kuroshio waters (0–60 m depth) and the transition waters (surface) between the Kuroshio and Oyashio fronts of the western North Pacific. The present larvae of C. macropus are distinguished from those of Paracaristius maderensis that inhabit the North Pacific by having 39–40 myomeres, 34 dorsal-fin rays, and 22 anal-fin rays. The present study, along with previous studies of the early life stages of caristiids, shows that larvae of the family may be defined by the following characters: body elongate in preflexion stage but becoming deep bodied and hatchet shaped after notochord flexion; anus located near vertical through base of pectoral fin; head large, without spination or serration; a distinct vertical band on the posterior tail throughout the larval stages, and two bands gradually appearing on the tail and trunk during the flexion and postflexion stages; and melanophores present around the notochord tip by the flexion stage. Adult C. macropus are found in the subarctic and temperate waters of the North Pacific; however, the present study and other occurrences of early life stages of the species probably indicate that C. macropus may spawn over a wide area in the North Pacific.  相似文献   
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A 3-hydroxyethyl-4-cyanoazetidin-2-one derivative (2) was synthesized from (2R,3R)-potassium 2,3-epoxybutyrate through two steps, and it was then further converted to a diazo derivative (7).  相似文献   
125.
Leptothrix cholodnii is an aerobic sheath-forming bacterium often found in oligotrophic and metal-rich aquatic environments. The sheath of this bacterium was isolated by selectively lysing the cells. Glycine and cysteine were the major amino acids of the sheath. The sheath was readily dissolved in hydrazine, and a polysaccharide substituted with cysteine was recovered from the solution. Galactosamine, glucosamine and galacturonic acid were detected in the hydrazinolysate by gas liquid chromatography analysis. FAB-MS analysis of the hydrazinolysate suggested a sugar sequence of HexN-GalA-HexN-HexN. Methylation linkage analysis revealed the presence of 4-linked GalA, 3-linked HexN and 4-linked HexN. The sulfhydryl groups of the sheath were used for labeling with the fluorogenic reagent, 4-(aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (ABD-F). The labeled sheath (ABD-sheath) was partially hydrolyzed and three fluorescent fragments were purified by HPLC. One of them was identified as ABD-cysteine. The second one was found to be the ABD-cysteine tetramer. Another fragment was indicated to be a pentasaccharide substituted with ABD-cysteine by nuclear magnetic resonance (NMR) analysis. It can be assumed that the polysaccharide and peptide moieties of the sheath are connected by a cysteine residue. NMR analysis of the hydrazinolysate revealed that the polysaccharide moiety of the sheath was constructed from a pentasaccharide repeating unit containing 2-amino-2-deoxygalacturonic acid (GalNA), as shown below. -->4)-alpha-GalNA-(1-->4)-alpha-D-GalN(p)-(1-->4)-alpha-D-GalA(p)-(1-->4)-beta-D-GlcN(p)-(1-->3)-beta-D-GalN(p)-(1-->.  相似文献   
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Regulation of progesterone receptor (PR) by estradiol-17beta (E(2)) in mouse uterine and vaginal epithelia was studied. In ovariectomized mice, PR expression was low in both vaginal stroma and epithelium, but high in uterine epithelium. E(2) induced PR in vaginal epithelium and stroma, but down-regulated PR in uterine epithelium. Analysis of estrogen receptor alpha (ERalpha) knockout (ERKO) mice showed that ERalpha is essential for E(2)-induced PR expression in both vaginal epithelium and stroma, and for E(2)-induced down-regulation, but not constitutive expression of PR in uterine epithelium. Regulation of PR by E(2) was studied in vaginal and uterine tissue recombinants made with epithelium and stroma from wild-type and ERKO mice. In the vaginal tissue recombinants, PR was induced by E(2) only in wild-type epithelium and/or stroma. Hence, in vagina, E(2) induces PR directly via ERalpha within the tissue. Conversely, E(2) down-regulated epithelial PR only in uterine tissue recombinants constructed with wild-type stroma. Therefore, down-regulation of uterine epithelial PR by E(2) requires stromal, but not epithelial, ERalpha. In vitro, isolated uterine epithelial cells retained a high PR level with or without E(2), which is consistent with an indirect regulation of uterine epithelial PR in vivo. Thus, E(2) down-regulates PR in uterine epithelium through paracrine mechanisms mediated by stromal ERalpha.  相似文献   
128.
Myocarditis is a critical inflammatory disorder which causes life-threatening conditions. No specific or effective treatment has been established. DPP-4 inhibitors have salutary effects not only on type 2 diabetes but also on certain cardiovascular diseases. However, the role of a DPP-4 inhibitor on myocarditis has not been investigated. To clarify the effects of a DPP-4 inhibitor on myocarditis, we used an experimental autoimmune myocarditis (EAM) model in Balb/c mice. EAM mice were assigned to the following groups: EAM mice group treated with a DPP-4 inhibitor (linagliptin) (n = 19) and those untreated (n = 22). Pathological analysis revealed that the myocardial fibrosis area ratio in the treated group was significantly lower than in the untreated group. RT-PCR analysis demonstrated that the levels of mRNA expression of IL-2, TNF-α, IL-1β and IL-6 were significantly lower in the treated group than in the untreated group. Lymphocyte proliferation assay showed that treatment with the DPP-4 inhibitor had no effect on antigen-induced spleen cell proliferation. Administration of the DPP-4 inhibitor remarkably suppressed cardiac fibrosis and reduced inflammatory cytokine gene expression in EAM mice. Thus, the agents present in DPP-4 inhibitors may be useful to treat and/or prevent clinical myocarditis.  相似文献   
129.
Kurita  Yoshihisa  Kijima  Akihiro 《Hydrobiologia》2019,829(1):237-243

Genetic studies play a great role for determining the biology of bivalves, particularly those covering population genetics, phylogeny, breeding, stock management, and conservation. However, DNA sampling methods that require removal of bivalves from the water and/or opening of their shells often cause stress and damage to bivalves, which can be lethal. The invasiveness of DNA sampling has made it difficult to conduct genetic studies in threatened species, rare species, and/or breeding lineages. In the present study, we developed a non-invasive method for bivalve DNA sampling using the water-filled mantle cavity (WMC). Our method can extract DNA from a small WMC sample (about 100 µl), collected using a fine needle and syringe without opening the shell. We demonstrated that the WMC sample contains intact mitochondrial and nuclear DNA. DNA contamination from other organisms, such as adjacent bivalve individuals, did not affect the resulting PCR and DNA sequencing analyses. Finally, the individuals from whom WMC was collected remained alive for more than 2 months after the experiments. This non-invasive method will be of great assistance in investigating the genetics of bivalves.

  相似文献   
130.
We performed a real-time PCR assay to detect herpes simplex virus (HSV) DNA, and compared it prospectively with a nested PCR assay in 164 clinical samples (109 cerebrospinal fluid and 55 sera) from patients suspected of having neonatal HSV infection or HSV encephalitis. In 25 of 164 samples, HSV DNA was detected by the nested PCR assay. All samples positive for HSV DNA in the nested PCR assay were also positive in the real-time PCR assay, and all but two samples negative for HSV DNA in the nested assay were negative in the real-time assay. The real-time PCR assay thus had a sensitivity of 100% and a specificity of 99%, when compared with the nested assay. Sequential assays in a case of disseminated HSV showed that a decrease in HSV DNA paralleled clinical improvement. Quantification of HSV DNA by real-time PCR was useful for diagnosing and monitoring patients with HSV encephalitis and neonatal HSV infection.  相似文献   
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