76
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Kakinuma S, Kodama Y, Amasaki Y, Yi S, Tokairin Y, Arai M, Nishimura M, Monobe M, Kojima S, Shimada Y. Ikaros is a mutational target for lymphomagenesis in Mlh1-deficient mice. Oncogene 2006; 26:2945-9. [PMID: 17086208 DOI: 10.1038/sj.onc.1210100] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Deficiencies in DNA mismatch repair (MMR) result in replication errors within key tumor suppressor genes or oncogenes, and cause hereditary nonpolyposis colorectal cancer (HNPCC). Hematological malignancy with microsatellite instability is also associated with defective MMR, but little is known about the target genes for MMR. Here we identified Ikaros, a master transcription factor of lymphoid lineage commitment and differentiation, as a mutational target in spontaneous and radiation-induced T-cell lymphomas in Mlh1-deficient mice. Three quarters of lymphomas lacked Ikaros protein expression, which resulted from a frameshift mutation that created a stop codon. Mononucleotide repeat sequences at 1029-1034(C)6 and 1567-1572(G)6 in Ikaros were mutational hot spots with a one-base deletion occurring with a frequency of 45 and 50%, respectively. Point mutations and splicing alterations were also observed. In total, 85% of the lymphomas showed aberrations in Ikaros. The characteristic of Mlh1-deficient lymphomas is harboring of multiple mutations simultaneously in the same tumor, displaying a combination of two frameshift mutations at different repeats, frameshift and point mutations, and/or deletion mutations. This is the first report of Ikaros mutations coupled with Mlh1 deficiency in lymphomagenesis.
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77
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Yang F, Shi P, Xi X, Yi S, Li H, Sun Q, Sun M. Recombinant adenoviruses expressing TRAIL demonstrate antitumor effects on non-small cell lung cancer (NSCLC). Med Oncol 2006; 23:191-204. [PMID: 16720919 DOI: 10.1385/mo:23:2:191] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2005] [Revised: 11/30/1999] [Accepted: 09/13/2005] [Indexed: 11/11/2022]
Abstract
INTRODUCTION Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in a variety of malignant cells, but not in normal cells. This preferential toxicity to the abnormal cells renders TRAIL potentially a very powerful therapeutic weapon against cancer. However, a requirement for large quantities of TRAIL to suppress tumor growth in vivo is one of the major factors that has hindered it from being widely applied clinically. To overcome this, we constructed a replication-deficient adenovirus that carries a human full-length TRAIL gene (Ad-TRAIL) and tested its efficacy against a lung cancer model system in comparison to that of the recombinant soluble TRAIL protein. METHODS To investigate the antitumor activity and therapeutic value of the Ad-TRAIL on the non-small cell lung cancer (NSCLC), four NSCLC cell lines, namely, YTMLC, GLC, A549, and H460 cells, were used. TRAIL protein expression was determined by Western blotting and flow cytometry. Cell viability was analyzed by proliferation assay, and DNA ladder and cell-cycle analysis were used to identify apoptosis. To further evaluate the effect of Ad-TRAIL in vivo, YTMLC cells were inoculated to the subcutis of nude mice. The Ad-TRAIL was subsequently administered into the established tumors. Tumor growth and the TRAIL toxicity were evaluated after treatment. RESULTS YTMLC cells infected with Ad-TRAIL showed decreased cell viability and a higher percentage of apoptosis. Similar, Ad-TRAIL treatment also significantly suppressed tumor growth in vivo. CONCLUSIONS TRAIL gene therapy provides a promising therapy for the treatment of NSCLC.
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MESH Headings
- Adenoviridae
- Animals
- Apoptosis/genetics
- Apoptosis Regulatory Proteins/biosynthesis
- Apoptosis Regulatory Proteins/genetics
- Carcinoma, Non-Small-Cell Lung/genetics
- Carcinoma, Non-Small-Cell Lung/metabolism
- Carcinoma, Non-Small-Cell Lung/therapy
- Carcinoma, Non-Small-Cell Lung/ultrastructure
- Cell Line, Tumor
- Cell Proliferation
- Genetic Therapy
- Humans
- Lung Neoplasms/genetics
- Lung Neoplasms/metabolism
- Lung Neoplasms/therapy
- Lung Neoplasms/ultrastructure
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/genetics
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/metabolism
- Neoplasms, Experimental/therapy
- Neoplasms, Experimental/ultrastructure
- TNF-Related Apoptosis-Inducing Ligand
- Tumor Necrosis Factor-alpha/biosynthesis
- Tumor Necrosis Factor-alpha/genetics
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78
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Sun B, Zhang WX, Yi S, Chapman MS, You L. Dipolar effect in coherent spin mixing of two atoms in a single optical lattice site. PHYSICAL REVIEW LETTERS 2006; 97:123201. [PMID: 17025962 DOI: 10.1103/physrevlett.97.123201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Indexed: 05/12/2023]
Abstract
We show that atomic dipolar effects are detectable in the system that recently demonstrated two-atom coherent spin dynamics within individual lattice sites of a Mott state. Based on a two-state approximation for the two-atom internal states and relying on a variational approach, we have estimated the spin dipolar effect. Despite the absolute weakness of the dipole-dipole interaction, it is shown that it leads to experimentally observable effects in the spin mixing dynamics.
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79
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Yoon DH, Yi S, Shin HC, Kim KN, Kim SH. Clinical and radiological results following cervical arthroplasty. Acta Neurochir (Wien) 2006; 148:943-50. [PMID: 16791434 DOI: 10.1007/s00701-006-0805-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Accepted: 04/25/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND This was a retrospective study of clinical and radiological results of cervical arthroplasty using the Bryan cervical disc prosthesis to evaluate the efficacy of arthroplasty in clinical applications. METHODS A total of 46 patients underwent arthroplasty of a single level using the Bryan disc prosthesis. Clinical outcome was assessed using the visual analogue scale (VAS) and the neck disability index (NDI). All patients were evaluated using preoperative and postoperative static cervical spine radiographs to compare cervical sagittal balance. Dynamic cervical spine radiographs were used to compare movement at the level of the procedure, movement at the adjacent level and movement of the whole cervical spine. FINDINGS With the exception of four patients with aggravated neck pain, the NDI and VAS scores decreased significantly in late follow-up evaluations. The range of movement of the whole cervical spine, the functional segmental unit, and the adjacent segments were preserved after arthroplasty. The sagittal alignment of the cervical spine showed kyphosis after surgery but restored lordosis at a later time. The postulated cause of kyphotic changes include "over-milling" at the dorsal endplate, inappropriate angle of disc insertion, structural absence of lordosis in the Bryan disc, removal of posterior longitudinal ligament, and pre-existing kyphosis. CONCLUSIONS Arthroplasty using the Bryan disc appears to be safe and provided a favorable preliminary clinical and radiological outcome. Postoperative kyphosis can be prevented by understanding the biomechanical properties of the Bryan disc. Future studies will need to address the association between postoperative kyphosis, clinical outcome and adjacent segment disease.
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80
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Yi S, Pu H. Spontaneous spin textures in dipolar spinor condensates. PHYSICAL REVIEW LETTERS 2006; 97:020401. [PMID: 16907420 DOI: 10.1103/physrevlett.97.020401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Indexed: 05/11/2023]
Abstract
We have mapped out a detailed phase diagram that shows the ground state structure of a spin-1 condensate with magnetic dipole-dipole interactions. We show that the interplay between the dipolar and the spin-exchange interactions induces a rich variety of quantum phases that exhibit spontaneous magnetic ordering in the form of intricate spin textures.
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81
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Yi S, Zhou P, Chang L, Hendry J. 221 Radiosensitisation of tumour cells by the HIV-1 TAT protein. Radiother Oncol 2006. [DOI: 10.1016/s0167-8140(06)80698-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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82
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Liu J, Liu Z, Yi S, Cui S. Islet-1 expression and its colocalization with luteinising hormone, thyroid-stimulating hormone and oestrogen receptor alpha in the developing pituitary gland of the sheep foetus. J Neuroendocrinol 2005; 17:773-80. [PMID: 16280024 DOI: 10.1111/j.1365-2826.2005.01364.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Islet-1 has been reported to be involved in pituitary development in the early stages of mouse embryogenesis. Oestrogen receptor (ER) and its expression may be involved in regulating pituitary development and its hormone-secreting function. Islet-1 expression and its correlations to ER in the developing pituitary gland are unknown. We therefore determined the pituitary cell specific expression of Islet-1 and its colocalization with ER alpha (ERalpha) in sheep foetus by immunohistochemistry. The results demonstrated that Islet-1-immunoreactive (ir) cells were distributed throughout the pituitary gland from day 60 of gestation until birth. The Islet-1-ir cell number was significant higher at day 90 and 120 of gestation compared to that at day 60 and at birth. All of the ERalpha-ir cells were colocalized with Islet-1 at day 60 of gestation, although a few ERalpha-ir cells were negative for Islet-1 in the later stage of gestation. The dominant cell type expressing Islet-1 is the gonadotroph, although small proportions of thyrotrophs and lactotrophs also express Islet-1. The proportion of luteinising hormone-ir gonadotrophs possessing Islet-1 kept rising from day 60 to day 120 of gestation and persisted until birth. The proportion of thyroid-stimulating hormone-ir cells expressing Islet-1 was at a high level from day 60-120 of the gestation and significantly declined at birth. The percentage of prolactin (PRL)-ir cells expressing Islet-1 was about 20% at day 60 of gestation. Very few PRL-ir cells contained Islet-1 in later stages of gestation. These data suggest that the development and functional establishment of pituitary gonadotrophs, thyrotrophs and lactotrophs might be regulated by the expressions of Islet-1 and ERalpha and by their interactions, although any mechanisms need to be elucidated further.
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83
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Li WW, Li VW, Vasan N, Kruger E, Haber M, Adler AS, Yi S, Bonar CJ. Efficacy of an Oral Antiangiogenic Protocol for Advanced Malignancies: A Pilot Study. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.3213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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84
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Pu H, Baksmaty LO, Yi S, Bigelow NP. Structural phase transitions of vortex matter in an optical lattice. PHYSICAL REVIEW LETTERS 2005; 94:190401. [PMID: 16090154 DOI: 10.1103/physrevlett.94.190401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2004] [Indexed: 05/03/2023]
Abstract
We consider the vortex structure of a rapidly rotating trapped atomic Bose-Einstein condensate in the presence of a corotating periodic optical lattice potential. We observe a rich variety of structural phases which reflect the interplay of the vortex-vortex and vortex-lattice interactions. The lattice structure is very sensitive to the ratio of vortices to pinning sites and we observe structural phase transitions and domain formation as this ratio is varied.
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85
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Yi S, You L, Pu H. Quantum phases of dipolar spinor condensates. PHYSICAL REVIEW LETTERS 2004; 93:040403. [PMID: 15323738 DOI: 10.1103/physrevlett.93.040403] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2003] [Indexed: 05/24/2023]
Abstract
We study the zero-temperature ground state structure of a spin-1 condensate with magnetic dipole-dipole interactions. We show that the dipolar interactions break the rotational symmetry of the Hamiltonian and induce new quantum phases. Different phases can be reached by tuning the effective strength of the dipolar interactions via modifying the trapping geometry. The experimental feasibility of detecting these phases is investigated. The spin-mixing dynamics is also studied.
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86
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Shah MA, Kortmansky J, Gonen M, Tse A, Lefkowitz R, Kelsen D, Colevas D, Winkelman J, Yi S, Schwartz G. A phase I study of weekly irinotecan (CPT), cisplatin (CIS) and flavopiridol (F). J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.4027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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87
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Kortmansky JS, Sauter N, O'Reilly E, Shah M, Abou-Alfa GK, Winkelmann J, Yi S, Gonen M, Kelsen DP, Schwartz GK. Management of hyperglycemia in patients with metastatic pancreatic cancer receiving UCN-01 and fluorouracil. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.2140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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88
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Yi S, You L. Calibrating dipolar interaction in an atomic condensate. PHYSICAL REVIEW LETTERS 2004; 92:193201. [PMID: 15169400 DOI: 10.1103/physrevlett.92.193201] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2003] [Indexed: 05/24/2023]
Abstract
We reexamine the topic of a dipolar condensate with the recently derived more rigorous pseudopotential for dipole-dipole interaction [Phys. Rev. A 67, 033607 (2003)]]. Based on the highly successful variational technique, we find that all dipolar effects estimated before (using the bare dipole-dipole interaction) become significantly larger, i.e., are amplified by the new velocity-dependent pseudopotential, especially in the limit of large or small trap aspect ratios. This result points to a promising prospect for detecting dipolar effects inside an atomic condensate.
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89
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Yi S, Müstecaplioğlu OE, You L. Quantum phase diffusions of a spinor condensate. PHYSICAL REVIEW LETTERS 2003; 90:140404. [PMID: 12731901 DOI: 10.1103/physrevlett.90.140404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2002] [Indexed: 05/24/2023]
Abstract
We discuss the quantum phases and their diffusion in a spinor-1 atomic Bose-Einstein condensate. For ferromagnetic interactions, we obtain the exact ground state distribution of the phase fluctuations corresponding to the total atom number (N), the magnetization (M), and the alignment (or hypercharge) (Y) of the system. The mean-field ground state is shown to be stable against these fluctuations, which dynamically recover the two continuous symmetries associated with the conservation of N and M as in current experiments.
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90
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Chung J, Cho J, Lim H, Hong K, Oh D, Yi S, Shin S, Jang I. Contribution of CYP3A5 genetic polymorphism in cyclosporine pharmacokinetics assessed from routine TDM data using mixed effect modeling. Clin Pharmacol Ther 2003. [DOI: 10.1016/s0009-9236(03)90565-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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91
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Bae K, Lim H, Hong K, Chung J, Yi S, Cho J, Jang I, Hong W, Shin S. Simultaneous Pharmacokinetic-Pharmacodynamic Modeling and Phase 2 Clinical Trial Simulation of A Reversible Proton Pump Inhibitor. Clin Pharmacol Ther 2003. [DOI: 10.1016/s0009-9236(03)90543-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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92
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Hong K, Lim H, Cho J, Chung J, Oh D, Yi S, Bae K, Jang I, Baik J, Shin S. Tolerability and single dose pharmacokinetics of a new PDE5 inhibitor, DA-8159 in healthy male subjects. Clin Pharmacol Ther 2003. [DOI: 10.1016/s0009-9236(03)90429-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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93
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Yi S, Tay JH, Maszenan AM, Tay STL. A culture-independent approach for studying microbial diversity in aerobic granules. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2003; 47:283-290. [PMID: 12578207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This study reports the use of ribosomal-based molecular techniques to study the microbial diversity in aerobic granules. Aerobic granules at different growth stages (young, mature and old) were obtained from a laboratory scale sequential aerobic sludge blanket (SASB) bioreactor fed with glucose as the main source of carbon and energy. Deoxyribonucleic acid (DNA) was extracted from the young, mature and old granules. The polymerase chain reaction (PCR) was used to amplify the Eubacterial 16S ribosomal DNA (rDNA) and three clone libraries were constructed, corresponding to each of the three growth stages. The microbial diversity in each clone library was assessed by amplified ribosomal DNA restriction analysis (ARDRA). The results reveal that there was considerable diversity in each clone library and there were variations in microbial diversity among the three different clone libraries. This suggests a shift in the composition of the microbial communities. Microorganisms associated with 5 restriction fragment length polymorphism (RFLP) types (A, B, C, D and E) appear to play an important role in the development of aerobic granules.
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94
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Takahara S, Moriyama T, Kokado Y, Hanafusa T, Yazawa K, Yi S, Tanaka T, Kojima Y, Tabata T, Oka K, Imai E. Randomized prospective study of effects of benazepril in renal transplantation: an analysis of safety and efficacy. Clin Exp Nephrol 2002. [DOI: 10.1007/s101570200041] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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95
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Arra M, Shangguan D, Yi S, Thalhammer R, Fockenberger H. Development of lead-free wave soldering process. ACTA ACUST UNITED AC 2002. [DOI: 10.1109/tepm.2002.807731] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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96
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Tay STL, Ivanov V, Yi S, Zhuang WQ, Tay JH. Presence of anaerobic bacteroides in aerobically grown microbial granules. MICROBIAL ECOLOGY 2002; 44:278-285. [PMID: 12219266 DOI: 10.1007/s00248-002-2014-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2002] [Accepted: 05/27/2002] [Indexed: 05/23/2023]
Abstract
Microbial granules were grown in a column-type sequential aerobic sludge blanket reactor inoculated with activated sludge flocs taken from a wastewater treatment plant and containing a medium with glucose as the main carbon source. The reactor selected for granules that could settle rapidly by employing a short settling time of 2 min. Matured granules with diameters between 2 and 3 micro m were examined for anaerobic bacteria as their presence can signal the onset of diffusion limitation problems that can potentially diminish granule stability due to the bacterial production of fermentation gases and organic acids under anaerobic conditions. To detect the anaerobes in the granules, clones were constructed from 16S rRNA PCR amplicons. Two sequence types associated with a strict anaerobe Bacteroides spp. were identified from these clones. Fluorescence in situ hybridization (FISH) followed by confocal laser scanning microscopy (CLSM) demonstrated that cells of Bacteroides spp. were concentrated at a depth of approximately 800 micro m below the surface of the granule. Cell enumeration using flow cytometry showed that the percentage of labeled cells of Bacteroides spp. compared to total bacterial cells in the granules was 0.56%. This is the first study to use a suite of culture-independent techniques to report the presence of a defined species of anaerobic bacteria in aerobically grown microbial granules.
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97
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Chian KS, Du XY, Goy HA, Feng JL, Yi S, Yue CY. Mechanical properties and morphology of poly(ethylene glycol)-side-chain-modified bismaleimide polymer. J Appl Polym Sci 2002. [DOI: 10.1002/app.10978] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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98
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Chian KS, Du XY, Goy HA, Feng JL, Yi S, Yue CY. Synthesis of bismaleimide resin containing the poly(ethylene glycol) side chain: Curing behavior and thermal properties. J Appl Polym Sci 2002. [DOI: 10.1002/app.10883] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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99
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Ohta T, Elnemr A, Yamamoto M, Ninomiya I, Fushida S, Nishimura GI, Fujimura T, Kitagawa H, Kayahara M, Shimizu K, Yi S, Miwa K. Thiazolidinedione, a peroxisome proliferator-activated receptor-γ ligand, modulates the E-cadherin/β-catenin system in a human pancreatic cancer cell line, BxPC-3. Int J Oncol 2002. [DOI: 10.3892/ijo.21.1.37] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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100
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Abstract
As-cast microstructure of Mg-rich Mg(68)Zn(28)Y(4) has been investigated by a detailed transmission electron microscopy study. The as-cast Mg(68)Zn(28)Y(4) alloy consisted of three different types of phases: 10-20 m size primary solidification phase, dendritic phase grown from the primary phase and a eutectic structure formed at the later stage of solidification. The primary solidification phase has an icosahedral structure with a large degree of phason strain. 1/1 rhombohedral approximant phase with lattice parameters a=27.2 A and =63.43 degrees is first observed in Mg-Zn-Y system. The rhombohedral structure can be obtained by introducing phason strain in the six-dimensional face centered hyper-cubic lattice. The decagonal phase nucleates with orientation relationship with the icosahedral phase, and Mg(4)Zn(7) nucleates with orientation relationship with the decagonal phase, indicating a close structural similarity between the three phases. Gradual depletion of Y during solidification plays an important role in heterogeneous nucleation of decagonal and Mg(4)Zn(7) phases from icosahedral and decagonal phases, respectively.
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