96 research outputs found
Microbial dark matter ecogenomics reveals complex synergistic networks in a methanogenic bioreactor
Ecogenomic investigation of a methanogenic bioreactor degrading terephthalate (TA) allowed elucidation of complex synergistic networks of uncultivated microorganisms, including those from candidate phyla with no cultivated representatives. Our previous metagenomic investigation proposed that Pelotomaculum and methanogens may interact with uncultivated organisms to degrade TA; however, many members of the community remained unaddressed because of past technological limitations. In further pursuit, this study employed state-of-the-art omics tools to generate draft genomes and transcriptomes for uncultivated organisms spanning 15 phyla and reports the first genomic insight into candidate phyla Atribacteria, Hydrogenedentes and Marinimicrobia in methanogenic environments. Metabolic reconstruction revealed that these organisms perform fermentative, syntrophic and acetogenic catabolism facilitated by energy conservation revolving around H2 metabolism. Several of these organisms could degrade TA catabolism by-products (acetate, butyrate and H2) and syntrophically support Pelotomaculum. Other taxa could scavenge anabolic products (protein and lipids) presumably derived from detrital biomass produced by the TA-degrading community. The protein scavengers expressed complementary metabolic pathways indicating syntrophic and fermentative step-wise protein degradation through amino acids, branched-chain fatty acids and propionate. Thus, the uncultivated organisms may interact to form an intricate syntrophy-supported food web with Pelotomaculum and methanogens to metabolize catabolic by-products and detritus, whereby facilitating holistic TA mineralization to CO2 and CH4
production of chitooligosaccharides from Rhizopus oligosporus NRRL2710 cells by chitosanase digestion
The intact cells of Rhizopus oligosporus NRRL2710, whose cell walls are abundant source of N-acetylglu- cosamine (GlcNAc) and glucosamine (GlcN), were digested with three chitinolytic enzymes, a GH-46 chitosanase from Streptomyces sp. N174 (CsnN174), a chitinase from Pyrococcus furiosus, and a chitinase from Trichoderma viride, respectively. Solubilization of the intact cells by CsnN174 was found to be the most efficient from solid state CP/MAS 13C NMR spectroscopy. Chitosanase products from Rhizopus cells were purified by cation exchange chromatography on CM-Sephadex C-25 and gel-filtration on Cellulofine Gcl-25 m. NMR and MALDI-TOF-MS analyses of the purified products revealed that GlcN–GlcNAc, (GlcN)2–GlcNAc, and (GlcN)2 were produced by the enzymatic digestion of the intact cells. The chitosan- ase digestion of Rhizopus cells was found to be an excellent system for the conversion of fungal biomass without any environmental impact
Draft Genome Sequence of Syntrophorhabdus aromaticivorans Strain UI, a Mesophilic Aromatic Compound-Degrading Syntroph
Syntrophorhabdus aromaticivorans strain UI is a mesophilic bacterium capable of degrading aromatic substrates in syntrophic cooperation with a partner methanogen. The draft genome sequence is 3.7 Mb, with a G+C content of 52.0%
Induction of Pluripotent Stem Cells from a Manifesting Carrier of Duchenne Muscular Dystrophy and Characterization of Their X-Inactivation Status
Three to eight percent of female carriers of Duchenne muscular dystrophy (DMD) develop dystrophic symptoms ranging from mild muscle weakness to a rapidly progressive DMD-like muscular dystrophy due to skewed inactivation of X chromosomes during early development. Here, we generated human induced pluripotent stem cells (hiPSCs) from a manifesting female carrier using retroviral or Sendai viral (SeV) vectors and determined their X-inactivation status. Although manifesting carrier-derived iPS cells showed normal expression of human embryonic stem cell markers and formed well-differentiated teratomas in vivo, many hiPS clones showed bi-allelic expression of the androgen receptor (AR) gene and loss of X-inactivation-specific transcript and trimethyl-histone H3 (Lys27) signals on X chromosomes, suggesting that both X chromosomes of the hiPS cells are in an active state. Importantly, normal dystrophin was expressed in multinucleated myotubes differentiated from a manifesting carrier of DMD-hiPS cells with XaXa pattern. AR transcripts were also equally transcribed from both alleles in induced myotubes. Our results indicated that the inactivated X chromosome in the patient’s fibroblasts was activated during reprogramming, and XCI occurred randomly during differentiation
診断用X線装置におけるコンプトン散乱X線スペクトルを用いた実効エネルギーの評価
90度コンプトン散乱X線スペクトルを用いて,診断用X線装置から発生するX線の実効エネルギーを評価し,その精度を従来の評価方法と比較した.90度散乱線から一次X線スペクトルに逆算すると,直接線と比較し,エネルギー分解能は若干劣るもののほぼ形状は一致した.さらに照射線量スペクトルに変換し,不規則な散乱線やノイズをカットするために17keV以上の部分についてAlによる減弱を計算し,半価層と実効エネルギーを算出した.透視条件において90度散乱線から算出した値は,直接線の値と比較し実効エネルギーで1~2%小さくなったが,ほぼ近い値が得られた.撮影条件では,測定条件を調整し計数率を1500cps以下にすると, 90度散乱線から算出した実効エネルギーはAl吸収板を用いた実測値と1%程度の誤差で一致した.これらの結果から,この評価方法は種々の診断用X線装置に応用できる簡便で有用な方法であると考えられた
Giant liver hemangioma resected by trisectorectomy after efficient volume reduction by transcatheter arterial embolization: a case report
<p>Abstract</p> <p>Introduction</p> <p>Liver hemangiomas are the most common benign liver tumors, usually small in size and requiring no treatment. Giant hemangiomas complicated with consumptive coagulopathy (Kasabach-Merritt syndrome) or causing severe incapacitating symptoms, however, are generally considered an absolute indication for surgical resection. Here, we present the case of a giant hemangioma, which was, to the best of our knowledge, one of the largest ever reported.</p> <p>Case presentation</p> <p>A 38-year-old Asian man was referred to our hospital with complaints of severe abdominal distension and pancytopenia. Examinations at the first visit revealed a right liver hemangioma occupying the abdominal cavity, protruding into the right diaphragm up to the right thoracic cavity and extending down to the pelvic cavity, with a maximum diameter of 43 cm, complicated with "asymptomatic" Kasabach-Merritt syndrome. Based on the tumor size and the anatomic relationship between the tumor and hepatic vena cava, primary resection seemed difficult and dangerous, leading us to first perform transcatheter arterial embolization to reduce the tumor volume and to ensure the safety of future resection. The tumor volume was significantly decreased by two successive transcatheter arterial embolizations, and a conventional right trisectorectomy was then performed without difficulty to resect the tumor.</p> <p>Conclusions</p> <p>To date, there have been several reports of aggressive surgical treatments, including extra-corporeal hepatic resection and liver transplantation, for huge hemangiomas like the present case, but because of its benign nature, every effort should be made to avoid life-threatening surgical stress for patients. Our experience demonstrates that a pre-operative arterial embolization may effectively enable the resection of large hemangiomas.</p
頭部SPECTにおけるステップと連続回転データ収集法の検討 : デジタルファントムによる検討
核医学検査における頭部SPECT検査を想定したステップ回転収集法と連続回転収集法による断層像のサンプリング角度の影響について,デジタルファントムを作成してシミュレーション解析による検討を行った.SPECTの連続回転収集法は,ステップ回転収集法のように検出器移動時の非データ収集というタイムロスが発生しない特徴があるが,標本化定理よりも大きなサンプリング角度を設定すると接線方向への画像歪が増加することが確認された.しかし,標本化定理に基づいたサンプリング角度を採用した場合は,連続回転収集法とステップ回転収集法によるSPECT像の画質がほぼ同等であることから,原理的に感度特性に優れた連続回転収集法を選択する方が良好な結果が得られると考えられた
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