12 research outputs found

    Asymmetric hydrogenation of N-substituted maleimides by cultured plant cells

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    The cultured suspension cells of higher plants hydrogenated the C-C double bond of N-substituted maleimides to afford corresponding succinimides. Hydrogenation of N-phenyl-2-methylmaleimide by the cultured cells of Nicotiana tabacum was highly-enantiospecific to give (R)-N-phenyl-2-methylsuccinimide (99 1.479619e-268.e.)

    日本の伝統的な漢方薬である大建中湯は推進性の運動パターンを誘導することにより結腸輸送を促進する

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    Background: The traditional Japanese herbal medicine, daikenchuto (DKT), has been used to treat constipation and postoperative ileus. However, the precise mechanisms involved in the pharmacological effects of DKT remain uncertain. The aim of this study was to clarify the effect of DKT on motor patterns and transit activity in the isolated rat colon. Methods: The entire colon or segments of the proximal colon in rats were isolated and placed in Krebs solution. The motility of the colon was evaluated by analyzing spatiotemporal maps of diameter derived from video imaging and measuring the intraluminal pressure in the anal end of the proximal colon, and the transit time of a plastic bead through the entire isolated colon. Key Results: Several types of propagating contractions were observed in the isolated entire colon. When DKT was added to Krebs solution, the frequency of large‐extent anal propagating contractions increased. DKT treatment increased the intraluminal pressure in the isolated proximal colon, which was related to the propagating contractions. This effect was abolished by treatment with the neural blocker tetrodotoxin. These findings suggest DKT induced peristaltic contractions in the isolated colon. DKT accelerated colonic transit activity, which was related to peristaltic contractions induction in the colon. These effects were also observed in the colons treated with bethanechol and the active ingredient of DKT, hydroxy‐α‐sanshool. Conclusions and Inferences: Daikenchuto could enhance colonic transit activity by inducing peristaltic contractions, which may be mediated by the activation of the enteric nervous system in the colon

    Biotransformation of sesquiterpenoids having α,β-unsaturated carbonyl groups with cultured plant cells of Marchantia polymorpha

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    The biotransformation of sesquiterpenoids having an α,β-unsaturated carbonyl group, such as -santonin (1), lancerodiol p-hydroxybenzoate (2), 8,9-dehydronootkatone (3) and nootkatone (4), with cultured suspension cells of Marchantia polymorpha was investigated. It was found that the C-C double bond of 1 and 2 was hydrogenated to give 1,2-dihydro--santonin (5) and 3,4-dihydrolancerodiol p-hydroxybenzoate (6), respectively, while the allylic position of the C-C double bond of 3 and 4 was hydroxylated to give 13-hydroxy-8,9-dehydronootkatone (7) and 9-hydroxynootkatone (8), respectively

    Comparison of the mesophilic cellulosome-producing Clostridium cellulovorans genome with other cellulosome-related clostridial genomes.

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    Clostridium cellulovorans, an anaerobic and mesophilic bacterium, degrades native substrates in soft biomass such as corn fibre and rice straw efficiently by producing an extracellular enzyme complex called the cellulosome. Recently, we have reported the whole-genome sequence of C. cellulovorans comprising 4220 predicted genes in 5.10 Mbp [Y. Tamaru et al., (2010) J. Bacteriol., 192: 901–902]. As a result, the genome size of C. cellulovorans was about 1 Mbp larger than that of other cellulosome-producing clostridia, mesophilic C. cellulolyticum and thermophilic C. thermocellum. A total of 57 cellulosomal genes were found in the C. cellulovorans genome, and they coded for not only carbohydrate-degrading enzymes but also a lipase, peptidases and proteinase inhibitors. Interestingly, two novel genes encoding scaffolding proteins were found in the genome. According to KEGG metabolic pathways and their comparison with 11 Clostridial genomes, gene expansion in the C. cellulovorans genome indicated mainly non-cellulosomal genes encoding hemicellulases and pectin-degrading enzymes. Thus, by examining genome sequences from multiple Clostridium species, comparative genomics offers new insight into genome evolution and the way natural selection moulds functional DNA sequence evolution. Our analysis, coupled with the genome sequence data, provides a roadmap for constructing enhanced cellulosome-producing Clostridium strains for industrial applications such as biofuel production

    Stereospecific hydrogenation of the C=C double bond of enones by Escherichia coli overexpressing an enone reductase of Nicotiana tabacum

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    We examined the biotransformation of enantiomeric pairs of enones such as pulegone and carvone in recombinant Escherichia coli expressing Nicotiana tabacum pulegone reductase. It was found that recombinant E. coli cells acquired the ability for stereospecific hydrogenation of the exocyclic Cdouble bond; length as m-dashC double bond of pulegone. However, stereospecificity in hydrogenation with the recombinant E. coli cells was opposite to that in hydrogenation with N. tabacum cells. On the other hand, the isolated recombinant pulegone reductase (rPRase) from the recombinant E. coli cells catalyzed hydrogenation of the exocyclic Cdouble bond; length as m-dashC double bond of pulegone; the hydrogen atoms participating in the reduction at C-8 and C-4 of pulegone originate from the pro-4R hydrogen of NADPH and the medium (H2O), respectively. Stereospecificity was lost in the hydrogenation of pulegone with the isolated rPRase, but was recovered when bovine serum albumin was added to the enzymatic reaction as an auxiliary factor

    Fulminant necrotizing eosinophilic myocarditis after COVID‐19 vaccination survived with mechanical circulatory support

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    Abstract A 69‐year‐old man was hospitalized for heart failure 7 days after coronavirus disease 2019 (COVID‐19) mRNA vaccination. Electrocardiography showed ST‐segment elevation and echocardiography demonstrated severe left ventricular dysfunction. Venoarterial extracorporeal membrane oxygenation and Impella 5.0 were instituted because of cardiogenic shock and ventricular fibrillation. Endomyocardial biopsy demonstrated necrotizing eosinophilic myocarditis (NEM). Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV2) PCR test was negative. He had no infection or history of new drug exposure. NEM was likely related to COVID‐19 vaccination. He was administered 10 mg/kg of prednisolone following methylprednisolone pulse treatment (1000 mg/day for 3 days). Left ventricular function recovered and he was weaned from mechanical circulatory support (MCS). Follow‐up endomyocardial biopsy showed no inflammatory cell infiltration. This is the first report of biopsy‐proven NEM after COVID‐19 vaccination survived with MCS and immunosuppression therapy. It is a rare condition but early, accurate diagnosis and early aggressive intervention can rescue patients
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