238 research outputs found
A Simple Enzymatic Method for Production of a Wide Variety of D-Amino Acids Using L-Amino Acid Oxidase from Rhodococcus sp. AIU Z-35-1
A simple enzymatic method for production of a wide variety of D-amino acids was developed by kinetic resolution of DL-amino acids using L-amino acid oxidase (L-AAO) with broad substrate specificity from Rhodococcus sp. AIU Z-35-1. The optimum pH of the L-AAO reaction was classified into three groups depending on the L-amino acids as substrate, and their respective activities between pH 5.5 and 8.5 accounted for more than 60% of the optimum activity. The enzyme was stable in the range from pH 6.0 to 8.0, and approximately 80% of the enzyme activity remained after incubation at 40°C for 60 min at pH 7.0. D-Amino acids such as D-citrulline, D-glutamine, D-homoserine or D-arginine, which are not produced by D-aminoacylases or D-hydantoinases, were produced from the racemic mixture within a 24-hr reaction at 30°C and pH 7.0. Thus, the present method using L-AAO was versatile for production of a wide variety of D-amino acids
Metastatic Carcinoma to Subcutaneous Tissue and Skeletal Muscle: Clinicopathological Features in 11 Cases
Objective: Metastatic carcinoma to subcutaneous tissue or skeletal muscle is relatively rare. The present study aimed to clarify the clinicopathological features for confirming the diagnosis as soft tissue metastasis and determining the primary site. Methods: We reviewed records of 11 patients with soft tissue metastasis who were in our institution from 1996 to 2009. Results: In 9 of 10 patients who underwent magnetic resonance imaging, findings consisted of poorly circumscribed high-intensity lesions around the tumor on T2-weighted images, irregular peritumoral enhancement and poorly enhanced lesions at the center of the tumor on T1-weighted images. Systematic immunohistochemical examination was more valuable for diagnosing as soft tissue metastasis and confirming the primary site. The expression patterns of cytokeratins 7 and 20 and tissue-specific antibodies such as thyroid transcription factor-1, MUC5AC and CDX2 were useful diagnostic markers. The primary site could be determined in five patients with cytokeratin 7/20 immunophenotype and positivity for tissue-specific antibodies. In four cases, determination of the primary site finally became possible by comparison with the histological findings of operative specimens in past carcinoma and/or in consideration of radiological findings and the results of cytokeratin 7/20 phenotyping. Conclusions: Systematic immunohistochemical examination is helpful for confirmation of the primary origin in soft tissue metastasis of carcinoma in addition to clinical information such as the history and condition of past carcinoma, radiological findings and comparison between the histology of biopsy specimens and past carcinoma.ArticleJAPANESE JOURNAL OF CLINICAL ONCOLOGY. 41(3):358-364 (2011)journal articl
Preoperative radiographic and histopathologic evaluation of central chondrosarcoma
Distinguishing grade 1 chondrosarcoma from grade 2 chondrosarcoma is critical both for planning the surgical procedure and for predicting the outcome. We aimed to review the preoperative radiographic and histologic findings, and to evaluate the reliability of preoperative grading. We retrospectively reviewed the medical records of 17 patients diagnosed with central chondrosarcoma at our institution between 1996 and 2011. In these cases, we compared the preoperative and postoperative histologic grades, and evaluated the reliability of the preoperative histologic grading. We also assessed the preoperative radiographic findings obtained using plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI). Preoperative histologic grade was 1 in 12 patients, 2 in 4 patients, and 3 in 1 patient. However, 6 of the 12 cases classified as grade 1 before surgery were re-classified as grade 2 postoperatively. In the radiographic evaluation, grade 1 was suspected by the presence of a ring-and-arc pattern of calcification on plain radiography and CT and entrapped fat and ring-and-arc enhancement on MRI. Grades 2 and 3 were suspected by the absence of calcification and the presence of cortical penetration and endosteal scalloping on plain radiography and CT, as well as soft-tissue mass formation on MRI. Although the combination of radiographic interpretation and histologic findings may improve the accuracy of preoperative grading in chondrosarcoma, the establishment of a standard evaluation system with the histologic and radiographic findings and/or the development of new biologic markers are necessary for preoperative discrimination of low-grade chondrosarcoma from high-grade chondrosarcoma.ArticleARCHIVES OF ORTHOPAEDIC AND TRAUMA SURGERY. 133(9):1225-1231 (2013)journal articl
Multifocal Periosteal Chondromas in the Ring Finger of an Adolescent Boy: Case Report
We describe an unusual case of a 12-year-old boy who presented with a loss of motion in the ring finger caused by 2 separate periosteal chondromas involving the proximal and middle phalanges. Range of motion improved and recurrence did not occur at the 5-year follow-up after marginal excision of both lesions. (J Hand Surg 2011;36A:101-105.ArticleJOURNAL OF HAND SURGERY-AMERICAN VOLUME. 36A(1):101-105 (2011)journal articl
Specific Serum-free Conditions can Differentiate Mouse Embryonic Stem Cells into Osteochondrogenic and Myogenic Progenitors.
Up-regulation of Gr1^+CD11b^+ cell population in the spleen of NaClO-administered mice works to repair skin wounds
名古屋大学Nagoya University博士(医学)In wound healing, early infiltration of neutrophils followed by macrophage infiltration are important defense mechanisms for repair of tissue damage. Here we examined the effects of neutrophils on wound healing. Administration of sodium hypochlorite (NaClO) to mouse skin induces neutrophil recruitment to the wound site and repeated administration of NaClO was shown to prolong wound healing. Examination of the spleens of mice whose wounds were repeatedly treated with NaClO, showed that GR-1^+CD11b^+ cells were up regulated in the recovery phase of wounding. Many of the GR-1^+CD11b^+ cells in the mouse bone marrow were neutrophils, as indicated by a ring-shaped nucleus, and some of the cells were immature myeloid-lineage cells. GR-1^+CD11b^+ cells from bone marrow were sorted and injected intravenously to syngeneic Imprinting Control Region (ICR) mice. The mice that received GR-1^+CD11b^+ cells recovered faster than the mice injected with the control, phosphate buffer saline (PBS).名古屋大学博士学位論文 学位の種類 : 博士(医学)(課程) 学位授与年月日:平成25年3月25日 原真由氏の博士論文として提出されたdoctoral thesi
Efficient induction of osteogenic and chondrogenic progenitors and myogenic progenitors from mouse ES cells in chemically defined medium
Embryonic stem (ES) cells and induced pluripotent stem (iPS) cells represent a renewable cellular resources for regenerative therapies. Here, we try to differentiate ES cells to paraxial mesodermal progenitors cells (PMPs), which give rise to osteogenic and chondrogenic progenitors and myogenic progenitors without fetal calf serum. Here, we demonstrate the methods for inducing paraxial mesodermal progenitors efficiently by treatment of BMP4 using PDGFR-a and ECD as markers for purifying them. The BMP4 induced PMPs exhibit fine potentials of differentiation to osto-and chondro-genic cells. Furthermore, early extraction of BMP4 and additional LiCl treatment promote the differentiation of myogenic progenitor cells. Further addition of IGF-1, bFGF and HGF induced the differentiation of PMPs to myocytes in vitro.journal articl
Cellular and systemic defense system against age-promoting stimuli
2006-01Although much progress has been achieved in aging research using lower animals, especially yeast and C. elegans, aging in humans remains puzzling. Here I offer my hypothesis of host defense against age-promoting stimuli, which holds that the cell itself has a defense system and multi-organism, an even more sophisticated one against age-promoting stimuli. Here I review recent achievements in aging research and try to explain their fi ndings in the light of my hypothesis. Age-promoting stimuli, including reactive oxygen species, telomere shortening or external stimuli such as UV or radiation induce stress responses in cells. The cellular defense system operates to overcome stimuli or repair damaged cellular components. Stress-induced damaged cells or infectious stimuli activate systemic defense systems, especially the innate immune system. Macrophages in the innate immune system are especially active not only in clearing damaged cells and repairing damaged tissue, but unfortunately, also in inducing age-related diseases.departmental bulletin pape
Diazotization of kynurenine by acidified nitrite secreted from indoleamine 2,3-dioxygenase-expressing myeloid dendritic cells
Indoleamine 2,3-dioxygenase (IDO)-initiated tryptophan metabolism along the kynurenine (Kyn) pathway regulates T-cell responses in some dendritic cells (DC) such as plasmacytoid DC. A Kyn assay using HPLC showed that samples were frequently deproteinized with trichloroacetic acid (TCA). In the present study, bone marrow derived myeloid DC (BMDC) were differentiated from mouse bone marrow cells with GM-CSF. CpG oligodeoxynucleotides (CpG) induced the expression of IDO protein with NO production in BMDC cultured for 24 hr. The concentrations of Kyn in the culture supernatants were not increased by stimulation with CpG but rather decreased by based on the Kyn assay after deproteinization with TCA. The level of Kyn exogenously added into the cell-free culture supernatant of BMDC stimulated with CpG was severely decreased by deproteinization with TCA but not methanol, and the decrease was prevented when BMDC was stimulated with CpG in the presence of a NOS inhibitor. Under acidic conditions, Kyn reacted with nitrite produced by BMDC, and generated a new compound that was not detected by Ehrlich reagent reacting with the aromatic amino residue of Kyn. An analysis by mass spectrometry showed the new compound to be a diazotization form of Kyn. In conclusion, the deproteinization of samples by acidic treatment should be avoided for the Kyn assay when NO is produced.journal articl
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