1,595 research outputs found
Stereospecificity of Thermostable Ornithine 5-Aminotransferase for the Hydrogen Transfer in the L- and D-Ornithine Transamination (MOLECULAR BIOFUNCTION-Molecular Microbial Science)
The thermostable ornithine 5-aminotransferase of a thermophile, Bacillus sp. YM-2 is unique in acting on both enantiomers of ornithine, although less effectively on the D-enantiomer. We studied the stereospecificity of the enzyme for the hydrogen abstraction from C-5 of the substrate moiety and the addition and removal of the hydrogen at C-4' of the cofactor (pyridoxal phosphate and pyridoxamine phosphate) moiety of the external Schiff base intermediate in the transamination of L- and D-ornithine. [5- 3H]L- and D-ornithines were prepared by incubation of L- and D-ornithines with the B. sp. YM-2 ornithine 5-aminotransferase in 3H2O, respectively. The C-5 of the tritiated L-and D-ornithine was proved to have the S-configuration with L-ornithine 5-aminotransferase of a mesophile, Bacillus sphaericus, catalyzing the stereospecific abstraction of pro-S hydrogen from C-5 of L-ornithine and amino acid racemase with lowsubstrate specificity of Pseudomonas putida . When apo-form of the enzyme was incubated with pyridoxamine 5'-phosphates that was stereospecifically tritiated at C-4' and 2-oxoglutarate in the presence of L-ornithine or D-ornithine, tritium was released exclusively from (4'S)-[4'-3H] pyridoxamine. These results suggest that the B. sp. YM-2 ornithine 5-aminotransferase stereospecifically abstracts the pro-S hydrogen from C-5 of L- and D-ornithine. The hydrogen abstracted is then transferred to C-4' of the cofactor moiety stereospecifically on the si face of the external Schiff base intermediate irrespective of the C-2 configuration of amino donor
Assessment of macular choroidal thickness by optical coherence tomography and angiographic changes in central serous chorioretinopathy.
[Objective]: To investigate the relationship between macular choroidal thickness measured by highpenetrating swept-source optical coherence tomography (SS-OCT) and angiographic findings in central serous chorioretinopathy (CSC). [Design]: Prospective cross-sectional case series. [Participants and Controls]: Thirty-four patients with CSC (44 eyes) and 17 volunteer subjects (17 normal eyes). [Methods]: All subjects underwent a comprehensive ophthalmologic and SS-OCT prototype examination. All patients with CSC also underwent simultaneous fluorescein angiography (FA) and indocyanine green angiography (IA). Mean regional choroidal thickness measurements on the Early Treatment Diabetic Retinopathy Study (ETDRS) layout and squared sector grids were obtained by 3-dimensional raster scanning using SS-OCT. [Main Outcome Measures]: Macular choroidal thickness and angiographic abnormalities. [Results]: Mean whole macular choroidal thickness in eyes with CSC (total, 329.3_83.0 _m; classic CSC, 326.9_83.1 _m; chronic CSC, 325.4_93.3 _m; and multifocal posterior pigment epitheliopathy, 359.0_15.5 _m) was greater than that in normal eyes (233.0_67.0_m) (P_ 0.001). In unilateral cases, mean whole macular choroidal thickness was greater in eyes with unilateral CSC than in unaffected fellow eyes (P_0.021). There was no significant difference in choroidal thickness between active eyes and resolved eyes in any of the ETDRS sectors. Mean choroidal thickness was greater in areas with leakage on FA than in areas without leakage (P_0.001). Mean choroidal thickness was greater in areas with choroidal vascular hyperpermeability and in areas with punctate hyperfluorescent spots on IA than in unaffected areas (P_0.001 for both). [Conclusions]: Increased choroidal thickness was observed in the whole macular area of eyes with any of the CSC subtypes. Choroidal thickness was related to leakage from the retinal pigment epithelium, choroidal vascular hyperpermeability, and punctate hyperfluorescent lesions. These findings provide evidence that CSC may be caused by focally increased hydrostatic pressure in the choroid. [Financial Disclosure(s)]: Proprietary or commercial disclosure may be found after the references
Pachychoroid neovasculopathy and age-related macular degeneration.
Pachychoroid neovasculopathy is a recently proposed clinical entity of choroidal neovascularization (CNV). As it often masquerades as neovascular age-related macular degeneration (AMD), it is currently controversial whether pachychoroid neovasculopathy should be distinguished from neovascular AMD. This is because its characteristics have yet to be well described. To estimate the relative prevalence of pachychoroid neovasculopathy in comparison with neovascular AMD and to investigate the phenotypic/genetic differences of the two diseases, we evaluated 200 consecutive Japanese patients who agreed to participate in the genetic study and diagnosed with pachychoroid neovasculopathy or neovascular AMD. Pachychoroid neovasculopathy was observed in 39 individuals (19. 5%), which corresponds to one fourth of neovascular AMD. Patients with pachychoroid neovasculopathy were significantly younger (p = 5. 1 × 10[−5]) and showed a greater subfoveal choroidal thickness (p = 3. 4 × 10[−14]). Their genetic susceptibility to AMD was significantly lower than that of neovascular AMD; ARMS2 rs10490924 (p = 0. 029), CFH rs800292 (p = 0. 013) and genetic risk score calculated from 11 AMD susceptibility genes (p = 3.8 × 10[−3]). Current results implicate that the etiologies of the two conditions must be different. Thus, it will be necessary to distinguish these two conditions in future studie
Focal choroidal excavation in eyes with central serous chorioretinopathy.
[Purpose]To study the prevalence and 3-dimensional (3-D) tomographic features of focal choroidal excavations in eyes with central serous chorioretinopathy (CSC) using swept-source optical coherence tomography (OCT). [Design]Prospective, cross-sectional study. [Methods]We examined 116 consecutive eyes with CSC with a prototype 3-D swept-source OCT. 3-D images of the shape of the macular area, covering 6 × 6 mm2, were reconstructed by segmentation of the outer surface of the retinal pigment epithelium (RPE). [Results]The 3-D swept-source OCT detected focal choroidal excavations in 9 eyes (7.8%). The 3-D scanning protocol, coupled with en face scans, allowed for clear visualization of the excavation morphology. In 5 eyes with focal excavations, unusual choroidal tissue was found beneath the excavation, bridging the bottom of the excavation and the outer choroidal boundary. Additionally, 3 of those 5 eyes showed a suprachoroidal space below the excavation, as if the outer choroidal boundary is pulled inward by this bridging tissue. The focal choroidal excavations were located within fluorescein leakage points and areas of choroidal hyperpermeability. Eyes with focal choroidal excavations were more myopic (−4.42 ± 2.92 diopters) than eyes without excavations (−0.27 ± 1.80 diopters, P = .001). Subfoveal choroidal thickness was significantly thinner (301.3 ± 60.1 μm) in eyes with focal excavations than in eyes without the excavations (376.6 ± 104.8 μm, P = .036). [Conclusions]Focal choroidal excavations were present in 7.8% of eyes with CSC. In these eyes, focal choroidal excavations may have formed from RPE retraction caused by focal scarring of choroidal connective tissue
fuys at the NTCIR-16 QA Lab-PoliInfo-3 Budget Argument Mining Subtask
This paper reports on the achievements of Budget Argument Mining subtask of the NTCIR-16 QA Lab-PoliInfo-3 task of fuys team. We have assigned ArgumentClass and RelatedID in different ways. ArgumentClass was assigned using BERT. We also thought that the accuracy could be improved by adding the flag indicating whether a speaker is a legislator or not ("giin-flag"). RelatedID was assigned using keyword extraction with TFIDF. The results showed good results for ArgumentClass, but the improvement in accuracy of RelatedID could not be confirmed. Although there was a difference in the results for the "giin-flag", the difference was small, and no advantage was found with or without the "giin-flag".conference pape
fuys Team at the NTCIR-17 UFO Task
This paper reports the results of the fuys team's NTCIR-17 UFO Text-to-Table Relationship Extraction (TTRE). Since we thought that Value cells depend on Name cells, we came up with a method that uses the result of extracting Name cells to connect them together. The text of a HTML tag and texts of cells were used to find Name. These two were encoded and combined to perform a binary classification. We tried several combinations of mark tag text and cell text. The best results were obtained using mark tags and tables in the same section of the same company. We tried two different rules for binding Value cells. The rule of finding a cell by the row and column combination of the cell that became the Name yielded good results.conference pape
fuys Team at the NTCIR-17 QA Lab-PoliInfo-4 Task
This paper reports on the fuys team's NTCIR-17 QA Lab-PoliInfo-4 Minutes-to-Budget Linking (MBLink) results. We thought that related tables could be found by focusing on the cells of the table. Learning inferences were made by combining the text of tag with an ID and the text of table cell. The two were encoded and combined to perform a binary classification. We considered a table relevant if there was at least one related word in the table's cells. We also tried this when the text of a table cell was joined column by column and combined with the text of a tag with an ID. The best accuracy was obtained when the text in table cells was joined column by column.conference pape
DS-CDMA wired bus with simple interconnection topology for parallel processing system LSIs
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