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Chen CY, Liu CL, Kao CL, Yeh HC, Li HT, Li WJ, Chang HW. Secondary Metabolites of Elaeagnus grandifolia. Chem Nat Compd 2020. [DOI: 10.1007/s10600-020-03130-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Li X, Kanegasaki S, Jin F, Deng Y, Kim JR, Chang HW, Tsuchiya T. Simultaneous induction of HSP70 expression, and degranulation, in IgE/Ag-stimulated or extracellular HSP70-stimulated mast cells. Allergy 2018; 73:361-368. [PMID: 28857181 DOI: 10.1111/all.13296] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2017] [Indexed: 12/26/2022]
Abstract
BACKGROUND In mast cells, induction of HSP70 expression during antigen stimulation has not been reported. METHODS Mouse bone marrow-derived mast cells (BMMC) were stimulated with IgE/Ag or HSP70. Induction of HSP70 expression and signaling protein phosphorylation were evaluated by immunoblotting. RESULTS HSP70 expression is induced in BMMC at an early stage of IgE/Ag-dependent stimulation, some of which is released from the cells in a granule-associated form. Induction of HSP70 expression was also observed with an IgE/Ag-stimulated human basophilic cell line, indicating that the phenomenon is not restricted to mouse BMMC. The induction of HSP70 expression, and its release, followed a similar time course to that of degranulation. Released HSP70 seems to be responsible for degranulation and production of eicosanoids, at least in part, because a neutralizing anti-HSP70 antibody mitigated these activities and because exogenous HSP70 not only induced immediate degranulation followed by autocrine HSP70 expression but also enhanced degranulation in IgE/Ag-stimulated BMMC. Extracellular HSP70 was found to induce phosphorylation of linker for activation of T cells (LAT) and a series of downstream signaling molecules in BMMC. We further found that Fyn, Lyn, and spleen tyrosine kinase (Syk), which are known to concern LAT phosphorylation in IgE/Ag-stimulated BMMC, were not phosphorylated in HSP70-stimulated BMMC, whereas lymphocyte-specific protein tyrosine kinase (Lck) was phosphorylated. CONCLUSION FcεRI stimulation in BMMC and basophils induces HSP70 expression and its release. Extracellular HSP70 induces degranulation and mediator release via phosphorylation of LAT.
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Affiliation(s)
- X. Li
- College of Pharmacy; Yeungnam University; Gyeongsan Korea
| | - S. Kanegasaki
- YU-ECI Research Center for Medical Science; Yeungnam University; Gyeongsan Korea
- College of Medicine; Yeungnam University; Daegu Korea
| | - F. Jin
- College of Pharmacy; Yeungnam University; Gyeongsan Korea
| | - Y. Deng
- College of Pharmacy; Yeungnam University; Gyeongsan Korea
| | - J.-R. Kim
- College of Medicine; Yeungnam University; Daegu Korea
| | - H. W. Chang
- College of Pharmacy; Yeungnam University; Gyeongsan Korea
| | - T. Tsuchiya
- YU-ECI Research Center for Medical Science; Yeungnam University; Gyeongsan Korea
- College of Medicine; Yeungnam University; Daegu Korea
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Maluchenko NV, Chang HW, Kozinova MT, Valieva ME, Gerasimova NS, Kitashov AV, Kirpichnikov MP, Georgiev PG, Studitsky VM. Inhibiting the pro-tumor and transcription factor FACT: Mechanisms. Mol Biol 2016. [DOI: 10.1134/s0026893316040087] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Li X, Kwon O, Kim DY, Taketomi Y, Murakami M, Chang HW. NecroX-5 suppresses IgE/Ag-stimulated anaphylaxis and mast cell activation by regulating the SHP-1-Syk signaling module. Allergy 2016; 71:198-209. [PMID: 26456627 DOI: 10.1111/all.12786] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2015] [Indexed: 11/28/2022]
Abstract
BACKGROUND IgE/Ag-stimulated mast cells release various pro-allergic inflammatory mediators, including histamine, eicosanoids, and pro-inflammatory cytokines. NecroX-5, a cell permeable necrosis inhibitor, showed cytoprotective effects in both in vitro and in vivo models. However, the anti-allergic effect of NecroX-5 has not yet been investigated. The aims of this study were to evaluate the anti-allergic activity of NecroX-5 in vivo and to investigate the underlying mechanism in vitro. METHODS The anti-allergic activity of NecroX-5 was evaluated in vitro using bone marrow-derived mast cells (BMMCs) and IgE receptor-bearing RBL-2H3 or KU812 cells and in vivo using a mouse model of passive anaphylaxis. The levels of histamine, eicosanoids (PGD2 and LTC4 ), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were measured using enzyme immunoassay kits. The mechanism underlying the action of NecroX-5 was investigated using immunoblotting, immunoprecipitation, and gene knockdown techniques. RESULTS NecroX-5 markedly inhibited mast cell degranulation and the synthesis of eicosanoids, TNF-α, and IL-6 by suppressing the activation of Syk, LAT, phospholipase Cγ1, MAP kinases, the Akt/NF-κB pathway, and intracellular Ca(2+) mobilization via the activation of phosphatase SHP-1. Oral administration of NecroX-5 effectively suppressed mast cell-dependent passive cutaneous and systemic anaphylactic reactions in a dose-dependent manner. CONCLUSIONS NecroX-5 might be a potential candidate for the development of a novel anti-allergic agent that suppresses IgE-dependent mast cells signaling.
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Affiliation(s)
- X. Li
- College of Pharmacy; Yeungnam University; Gyeongsan Gyeongbuk Korea
| | - O. Kwon
- College of Pharmacy; Yeungnam University; Gyeongsan Gyeongbuk Korea
| | - D. Y. Kim
- College of Pharmacy; Yeungnam University; Gyeongsan Gyeongbuk Korea
| | - Y. Taketomi
- Lipid Metabolism Project; Tokyo Metropolitan Institute of Medical Science; Tokyo Japan
| | - M. Murakami
- Lipid Metabolism Project; Tokyo Metropolitan Institute of Medical Science; Tokyo Japan
| | - H. W. Chang
- College of Pharmacy; Yeungnam University; Gyeongsan Gyeongbuk Korea
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Maluchenko NV, Chang HW, Kozinova MT, Valieva ME, Gerasimova NS, Kitashov AV, Kirpichnikov MP, Georgiev PG, Studitsky VM. [Inhibiting the pro-tumor and transcription factor FACT: Mechanisms]. Mol Biol (Mosk) 2016; 50:599-610. [PMID: 27668600 DOI: 10.7868/s002689841604008x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 01/13/2016] [Indexed: 11/23/2022]
Abstract
Conventional antitumor therapy is often complicated by the emergence of the so-called cancer stem cells (CSCs), which are characterized by low metabolic rates and high resistance to almost all existing therapies. Many problems of clinical oncology and a poor efficacy of current treatments in particular are ascribed to CSCs. Therefore, it is important to develop new compounds capable of eliminating both rapidly proliferating tumor cells and standard treatment-resistant CSCs. Curaxins have been demonstrated to manifest various types of antitumor activity. Curaxins simultaneously affect at least three key molecular cascades involved in tumor development, including the p53, NF-κB, and HSF1 metabolic pathways. In addition, studies of some curaxins indicate that they can inhibit the transcriptional induction of the genes for matrix metalloproteinases 1 and 8 (MMP1 and MMP8); the PI3K/AKT/mTOR signaling cascades; cIAP-1 (apoptosis protein 1) inhibitor activity; topoisomerase II; and a number of oncogenes, such as c-MYC and others. In vivo experiments have shown that the CSC population increases on gemcitabine monotherapy and is reduced on treatment with curaxin CBL0137. The data support the prospective use of FACT inhibitors as new anticancer drugs with multiple effects on cell metabolism.
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Affiliation(s)
- N V Maluchenko
- Biological Faculty, Moscow State University, Moscow, 119234 Russia.,
| | - H W Chang
- Fox Chase Cancer Center, Philadelphia, PA, 19111-2497, USA
| | - M T Kozinova
- Fox Chase Cancer Center, Philadelphia, PA, 19111-2497, USA
| | - M E Valieva
- Biological Faculty, Moscow State University, Moscow, 119234 Russia
| | - N S Gerasimova
- Biological Faculty, Moscow State University, Moscow, 119234 Russia.,Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334 Russia
| | - A V Kitashov
- Biological Faculty, Moscow State University, Moscow, 119234 Russia
| | - M P Kirpichnikov
- Biological Faculty, Moscow State University, Moscow, 119234 Russia
| | - P G Georgiev
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334 Russia
| | - V M Studitsky
- Biological Faculty, Moscow State University, Moscow, 119234 Russia.,Fox Chase Cancer Center, Philadelphia, PA, 19111-2497, USA.,Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334 Russia.,
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Kim JM, Son CN, Chang HW, Kim SH. Simultaneous presentation of acute disseminated encephalomyelitis (ADEM) and systemic lupus erythematosus (SLE) after enteroviral infection: can ADEM present as the first manifestation of SLE? Lupus 2014; 24:633-7. [PMID: 25488421 DOI: 10.1177/0961203314560426] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 10/28/2014] [Indexed: 11/15/2022]
Abstract
Central Nervous System (CNS) involvement of Systemic Lupus Erythematosus (SLE) includes a broad range of neuropsychiatric syndromes. Acute Disseminated Encephalomyelitis (ADEM) is a demyelinating CNS disorder characterized by encephalopathy and multifocal lesions predominantly involving the white matter on brain magnetic resonance imaging. ADEM associated with SLE has been only rarely reported. We report an unusual case of a 17-year-old girl who developed ADEM after enteroviral infection as the first manifestation of SLE. The authors emphasize that the patient's illness was preceded by enteroviral infection and that ADEM occurred before any other symptoms of SLE, which makes this case unique.
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Affiliation(s)
- J-M Kim
- Division of Rheumatology, Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea
| | - C-N Son
- Division of Rheumatology, Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea
| | - H W Chang
- Department of Radiology, Keimyung University School of Medicine, Daegu, Korea
| | - S-H Kim
- Division of Rheumatology, Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea
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Nambiar V, Sohn SI, Almekhlafi MA, Chang HW, Mishra S, Qazi E, Eesa M, Demchuk AM, Goyal M, Hill MD, Menon BK. CTA collateral status and response to recanalization in patients with acute ischemic stroke. AJNR Am J Neuroradiol 2013; 35:884-90. [PMID: 24371030 DOI: 10.3174/ajnr.a3817] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Collateral status at baseline is an independent determinant of clinical outcome among patients with acute ischemic stroke. We sought to identify whether the association between recanalization after intra-arterial acute stroke therapy and favorable clinical response is modified by the presence of good collateral flow assessed on baseline CTA. MATERIALS AND METHODS Data are from the Keimyung Stroke Registry, a prospective cohort study of patients with acute ischemic stroke from Daegu, South Korea. Patients with M1 segment MCA with or without intracranial ICA occlusions on baseline CTA from May 2004 to July 2009 who also had baseline MR imaging were included. Two readers blinded to all clinical information assessed baseline and follow-up imaging. Leptomeningeal collaterals on baseline CTA were assessed by consensus by use of the regional leptomeningeal score. RESULTS Among 84 patients (mean age, 65.2 ± 13.2 years; median NIHSS score, 14; interquartile range, 8.5), median time from stroke onset to initial MR imaging was 164 minutes. TICI 2b-3 recanalization was achieved in 38.1% of patients and mRS 0-2 at 90 days in 35.8% of patients. In a multivariable model, the interaction between collateral status and recanalization was significant. Only patients with intermediate or good collaterals who recanalized showed a statistically significant association with good clinical outcome (rate ratio = 3.8; 95% CI, 1.2-12.1). Patients with good and intermediate collaterals who did not achieve recanalization and patients with poor collaterals, even if they achieved recanalization, did not do well. CONCLUSIONS Patients with good or intermediate collaterals on CTA benefit from intra-arterial therapy, whereas patients with poor collaterals do not benefit from treatment.
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Affiliation(s)
- V Nambiar
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)
| | - S I Sohn
- Departments of Neurology (S.I.S.)
| | - M A Almekhlafi
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)Department of Internal Medicine (M.A.A.), King Abdulaziz University, Jeddah, Saudi Arabia
| | - H W Chang
- Radiology (H.W.C.), Brain Research Institute, Keimyung University, Daegu, South Korea
| | - S Mishra
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)
| | - E Qazi
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)
| | - M Eesa
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)Radiology (M.E., A.M.D., M.G., M.D.H., B.K.M.)
| | - A M Demchuk
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)Radiology (M.E., A.M.D., M.G., M.D.H., B.K.M.)Hotchkiss Brain Institute (A.M.D., M.G., M.D.H., B.K.M.), University of Calgary, Calgary, Alberta, Canada
| | - M Goyal
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)Radiology (M.E., A.M.D., M.G., M.D.H., B.K.M.)Hotchkiss Brain Institute (A.M.D., M.G., M.D.H., B.K.M.), University of Calgary, Calgary, Alberta, Canada
| | - M D Hill
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)Radiology (M.E., A.M.D., M.G., M.D.H., B.K.M.)Community Health Sciences (M.D.H., B.K.M.), University of Calgary, Calgary, Alberta, CanadaHotchkiss Brain Institute (A.M.D., M.G., M.D.H., B.K.M.), University of Calgary, Calgary, Alberta, Canada
| | - B K Menon
- From the Calgary Stroke Program, Departments of Clinical Neurosciences (V.N., M.A.A., S.M., E.Q., M.E., A.M.D., M.G., M.D.H., B.K.M.)Radiology (M.E., A.M.D., M.G., M.D.H., B.K.M.)Community Health Sciences (M.D.H., B.K.M.), University of Calgary, Calgary, Alberta, CanadaHotchkiss Brain Institute (A.M.D., M.G., M.D.H., B.K.M.), University of Calgary, Calgary, Alberta, Canada.
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Affiliation(s)
- J W Chou
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, China Medical University Hospital, China Medical University, North District Taichung, Taiwan
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Lee SJ, Son KH, Chang HW, Kang SS, Kim HP. Inhibition of arachidonate release from rat peritoneal macrophage by biflavonoids. Arch Pharm Res 2012; 20:533-8. [PMID: 18982255 DOI: 10.1007/bf02975207] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/1997] [Indexed: 11/26/2022]
Abstract
Biflavonoid is one of unique classes of naturally-occurring bioflavonoid. Previously, certain biflavonoids were found to possess the inhibitory effects on phospholipase A(2) activity and lymphocytes proliferation(1) suggesting their anti-inflammatory/immunoregulatory potential. In this study, effects of several biflavonoids on arachidonic acid release from rat peritoneal macrophages were investigated, because arachidonic acid released from the activated macrophages is one of the indices of inflammatory conditions. When resident peritoneal macrophages labeled with [(3)H]arachidonic acid were activated by phorbol 12-myristate 13-acetate (PMA) or calcium ionophore, A23187, radioactivity released in the medium was increased approximately 4.1 approximately 7.3 fold after 120 min incubation compared to the spontaneous release in the control incubation. In this condition, biflavonoids (10 uM) such as ochnaflavone, ginkgetin and isoginkgetin, showed inhibition of arachidonate release from macrophages activated by PMA (32.5 approximately 40.0% inhibition) or A23187 (21.7 approximately 41.7% inhibition). Amentoflavone showed protection only against PMA-induced arachidonate release, while apigenin, a monomer of these biflavonoids, did not show the significant inhibition up to 10 uM. Staurosporin (1 uM), a protein kinase C inhibitor, showed an inhibitory effect only against PMA-induced arachidonate release (96.8% inhibition). Inhibition of arachidonate release from the activated macrophages may contribute to an anti-inflammatory potential of biflavonoidsin vivo.
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Affiliation(s)
- S J Lee
- College of Pharmacy, Kangwon National University, 200-701, Chunchon, Korea
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Chang HW, Kim SH, Kim KH, Kim YJ. Combined anti-calcification treatment of bovine pericardium with amino compounds and solvents. Interact Cardiovasc Thorac Surg 2011; 12:903-7. [DOI: 10.1510/icvts.2010.259747] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Hsieh CC, Lin TH, Chang HW, Chang CW, Chang WC, Yang CC. Effect of dopants on the soft magnetic properties and high frequency characteristics of FeCoBM (M = Ti, Nb, Hf, and Ta) thin films. J Nanosci Nanotechnol 2011; 11:2752-2755. [PMID: 21449469 DOI: 10.1166/jnn.2011.2726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Effect of dopants on the soft magnetic properties and high frequency characteristics of FeCoBM thin films (M = Ti, Nb, Hf, and Ta) have been studied. For (Fe0.55Co0.45)(100-x)B(x) (x = 5-15) thin films, with the increase of B content, the resistivity was increased because B could decrease the crystallinity of the films. The (Fe0.55Co0.45)90B10 thin film showed the optimum properties, where 4piM(s) = 16.1 kG, H(ce) = 64.2 Oe, H(ch) = 13.5 Oe, H(k) = 310 Oe and p = 338 microomega-cm. To reduce the coercivity of the film, the elements M, including Ti, Nb, Hf, and Ta, were selected to substitute for B in the FeCoB films. It was found that (Fe0.55Co0.45)90B6Ti2Nb2 thin film after annealing at a temperature of 200 degrees C for 30 min showed the optimal properties, where 4piM(s) = 15.8 kG, H(ce) = 4.8 Oe, H(ch) = 3.6 Oe, H(k) = 224 Oe and p = 290 microomega-cm. The theoretically calculated ferromagnetic resonance frequency of the developed films can be higher than 5 GHz.
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Affiliation(s)
- C C Hsieh
- Department of Physics, National Chung Cheng University, Taiwan 621, ROC
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Chang HW, Chen CH, Hsieh CC, Chang WC. Magnetic properties of melt spun mischmetals-Fe-Ti-B nanocomposite ribbons. J Nanosci Nanotechnol 2011; 11:2756-2760. [PMID: 21449470 DOI: 10.1166/jnn.2011.2727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Magnetic properties and phase evolution of melt spun R9.5Fe(bal.)Ti2B10 (R = MM(A), MM(B), MM(C), Pr, Nd, Ce, and La) nanocomposites have been investigated. Based on the results for the X-ray diffraction and thermal magnetic analysis, only 2:14:1 and alpha-Fe phases appear for R = MM(A) and Pr, and an additional Fe3B phase is present for R = MM(B), MM(C), Nd, and Ce. Besides, the uniform fine grain size of 20-40 nm is almost unchanged for the ribbons with various rare earth elements. Accordingly, magnetic properties of MM9.5Fe(bal.)Ti2B10 nanocomposites are mainly dominated by the composition of Mischmetals or the rare earth elements adopted, and are consistent with the outcome for the combinations of magnetic properties of their corresponding R9.5Fe(bal.)Ti2B10 nanocomposites. In this study, the optimum magnetic properties of B(r) = 9.3 kG, (i)H(c) = 12.1 kOe and (BH)(max) = 18.0 MGOe can be achieved for MM(B)9.5Fe(bal.)Ti2B10 nanocomposites. They not only exhibit comparable magnetic properties to the commercial available powders but also reduce the original material cost effectively.
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Affiliation(s)
- H W Chang
- Department of Physics, Tunghai University, Taichung, Taiwan 407, ROC
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Chang HW, Tsay JS, Hung YC, Chan WY, Su WB, Chang CS, Yao YD. Investigation of magnetic properties and microstructure of ultrathin Co films grown on Si(111)- 7 x 7 surface. J Nanosci Nanotechnol 2011; 11:2696-2699. [PMID: 21449457 DOI: 10.1166/jnn.2011.2728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Magnetic properties and growth mechanism of ultrathin Co films on Si(111)-7 x 7 surface have been studied by using both surface magneto-optic Kerr effect (SMOKE) and scanning tunneling microscopy (STM), respectively. STM results show that the growth mechanism of ultrathin Co films on Si(111)-7 x 7 surface at room temperature belongs to Stranski-Krastanov (SK) growth mode. Due to formation of CoSi2 layer, no magnetic signal could be detected by SMOKE for 1-4 ML Co deposited on Si(111) surface. Because of rougher surface, both longitudinal and perpendicular magnetic anisotropy configuration appear for 4.2-10 ML Co/Si(111) films. When the Co thickness is increased to 10 ML, only longitudinal anisotropy configuration is found, resulting from the contribution to the volume anisotropy. Furthermore, in-plane coercivity increases with Co coverage because of enhancement of ferromagnetic coupling with Co thickness, out-of-plane coercivity increases with Co coverage due to the increment of demagnetized field, induced by the rougher Co surface and pinhole structures.
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Affiliation(s)
- H W Chang
- Department of Physics, Tunghai University, Taichung, 407 Taiwan, ROC
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Chang HW, Guo CS, Hsieh CC, Chang WC. Magnetic properties, phase evolution, and microstructure of melt spun Hf-substituted Sm(Co0.97Hf0.03)(x)Cy (x = 5-9; y = 0-0.1) nanocomposites. J Nanosci Nanotechnol 2011; 11:2722-2725. [PMID: 21449462 DOI: 10.1166/jnn.2011.2725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Magnetic properties, phase evolution, and microstructure of melt spun Hf-substituted Sm(Co0.97Hf0.03)(x)Cy (x = 5-9; y = 0-0.1) ribbons quenched at the wheel speed of 40 m/s are investigated. X-ray diffraction analysis shows that the main phases existed in Sm(Co0.97Hf0.03)(x) ribbons are 1:5 phase for x = 5-5.5; 1:5 and 1:7 phases for x = 6; 1:7 phase for x = 6.5-7.5; 1:7 and 2:17 phases for x = 8; and only 2:17 phase for x = 8.5-9, respectively. For Sm(Co0.97Hf0.03)(x) (x = 5-9) ribbons, the optimum magnetic properties of B(r) = 5.6 kG, (i)H(c)= 15.6 kOe and (BH)(max) = 7.1 MGOe are obtained for Sm(Co0.97Hf0.03)6.5 ribbons. Furthermore, a slight amount of C addition in Sm(Co0.97Hf0.03)(x) ribbons slightly modify phase constitution and effectively refine the grain size from 200-700 nm for C free ribbons to 10-70 nm, strengthening the exchange coupling effect between magnetic grains of the ribbons. As a result, magnetic properties are further improved. The magnetic properties of B(r) = 6.9 kG, (i)H(c) = 9.2 kOe and (BH)(max) = 10.0 MGOe can be achieved for Sm(Co0.97Hf0.03)7.5C0.1 nanocomposites.
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Affiliation(s)
- H W Chang
- Department of Physics, Tunghai University, Taichung 407, Taiwan
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Chang HW, Wu BF, Yao YD, Su WB, Chang CS. Co nanoislands on Au(111) and Cu(111) surfaces studied by scanning tunneling microscopy and spectroscopy. J Nanosci Nanotechnol 2010; 10:4663-4666. [PMID: 21128475 DOI: 10.1166/jnn.2010.1686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Co nanoislands on the Au(111) and Cu(111) surfaces have been studied by scanning tunneling microscopy and spectroscopy. The experimental results showed that Co nanoislands prefer to aggregate at the step edge and dislocation sites on the reconstructed Au(111) surface and at the step edge on the Cu(111) surface, respectively. In addition, based on dZ/dV-V spectra, in both the Co/Au(111) and the Co/Cu(111) systems, Gundlach oscillation was observed. From the peak shift of dZ/dV-V spectra between Co nanoisland and substrate surface, we can quantitatively obtain that the constant energy separation is -0.13 +/- 0.01 eV for the Co/Au(111) system, and 0.41 +/- 0.02 eV for the Co/Cu(111) system, respectively. These values indicate the work function difference between Co nanoisland and these surfaces.
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Affiliation(s)
- H W Chang
- Department of Physics, Tunghai University, Taichung, 407 Taiwan
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Lee DG, Lee SK, Chang HW, Kim JY, Lee HJ, Lee SM, Kwon JH, Woo S. CT features of lobular capillary hemangioma of the nasal cavity. AJNR Am J Neuroradiol 2009; 31:749-54. [PMID: 20007721 DOI: 10.3174/ajnr.a1908] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Lobular capillary hemangioma is a benign capillary proliferation of unknown etiology. To our knowledge, no comprehensive review of imaging findings of LCHNC has been presented. Thus, we investigated characteristic CT features of LCHNC. MATERIALS AND METHODS This retrospective study included 6 patients (2 men and 4 women; age range, 30-65 years; mean age, 49.2 years) with histologically proved LCHNC. We evaluated the size, site of origin, attenuation on NECT, degree and pattern of enhancement, and bony changes. RESULTS The LCHNC lesion was 13.0-45.0 mm (average, 25.0 mm) in diameter. These lesions arose from the inferior turbinate in 5 (83.3%) patients and the anterior nasal septum in 1 (16.7%). Compared with the masticator muscles, the LCHNC lesion was hypoattenuating in 2 (33.3%) and isoattenuating on NECT in 4 (66.7%) patients. In 5 (83.3%) patients, the LCHNC lesion consisted of 2 distinct areas on CECT: a lobular intensely enhancing mass and an iso- or hypoattenuating cap of variable thickness around the intensely enhancing mass. Bony changes included erosion in 3 (50.0%) and displacement in 2 (33.3%) patients. CONCLUSIONS CT features of LCHNC consist of an intensely enhancing mass and an iso- or hypoattenuating cap on CECT. The inferior turbinate seems to be a common site of origin, and bony changes are not uncommon features of LCHNC. CT is useful not only in identifying the site of origin and assessing the extent but also in suggesting the nature of LCHNC.
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Affiliation(s)
- D G Lee
- Department of Radiology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, South Korea
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Wu VC, Chueh SC, Chang HW, Lin WC, Liu KL, Li HY, Lin YH, Wu KD, Hsieh BS. Bilateral aldosterone-producing adenomas: differentiation from bilateral adrenal hyperplasia. QJM 2008; 101:13-22. [PMID: 18203722 DOI: 10.1093/qjmed/hcm101] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Primary aldosteronism (PA) is a common curable disease of secondary hypertension. Most such patients have either idiopathic bilateral adrenal hyperplasia (BAH) or unilateral aldosterone-producing adenoma (APA). Bilateral APAs are reportedly extremely rare. AIM To compare the distinctive characteristics, clinical course, and outcomes of bilateral APA vs. BAH. DESIGN Retrospective record review. METHODS From July 1994 to Jan 2007, 190 patients diagnosed with PA underwent surgical intervention at our hospital. Bilateral APA was diagnosed in 7/164 patients with histologically-proven APA. Twenty-one patients diagnosed as BAH, and 21 randomly selected of unilateral APA patients, matched by age and sex served as controls. RESULTS Patients with bilateral APA had similar blood pressure, arterial blood gas analysis, spot urinary potassium to creatinine ratio and clinical symptoms to those with BAH, but lower serum potassium levels (p = 0.027), lower plasma renin activity (p = 0.037), and higher plasma aldosterone concentrations (p = 0.029). Aldosterone-renin ratio (ARR) after administration of 50 mg captopril was higher in bilateral APA than in BAH patients (p = 0.023), but not different between unilateral APA and BAH (p = 0.218). A cut-off of ARR >100 ng/dl per ng/ml/h and plasma aldosterone >20 ng/dl after captopril significantly differentiated bilateral APA from BAH. Bilateral subtotal adrenalectomy normalized blood pressure and biochemistry in all patients with bilateral APA. DISCUSSION Bilateral APA, presenting simultaneously or sequentially, may not be a rare disease, accounting for 4.3% of APA in this sample. The clinical presentations of bilateral functional adenoma are not different from BAH, but patients with low serum potassium and ARR >100 after captopril should be carefully evaluated for bilateral adenoma.
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Affiliation(s)
- V C Wu
- Clinical Research Building, Department of Internal Medicine, National Taiwan University Hospital, No. 7 Chung-Shan South Road, Taipei 100, Taiwan
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Kim JH, Kim RH, Lee J, Chang HW. Hydrogeochemical characterization of major factors affecting the quality of shallow groundwater in the coastal area at Kimje in South Korea. ACTA ACUST UNITED AC 2003. [DOI: 10.1007/s00254-003-0782-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Huang CR, Lu CH, Chang HW, Lee PY, Lin MW, Chang WN. Community-acquired spontaneous bacterial meningitis in adult diabetic patients: an analysis of clinical characteristics and prognostic factors. Infection 2002; 30:346-50. [PMID: 12478323 DOI: 10.1007/s15010-002-3010-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND We analyzed the clinical characteristics and prognostic factors of community-acquired spontaneous bacterial meningitis (CASBM) in adult diabetic patients. PATIENTS AND METHODS Over a period of 15 years, 47 adult diabetic patients with CASBM were identified. The clinical characteristics, laboratory data and therapeutic outcome of these 47 patients were statistically analyzed. RESULTS The 47 patients were 31 men and 16 women, aged 22 to 79 years, and they accounted for 38.5% (47/122) of our adult patients with culture-proven CASBM. The most common causative pathogen was Klebsiella pneumoniae (n = 32), followed by pathogens of the streptococcal species (n = 6). Besides classic manifestations of bacterial meningitis, bacteremia and focal suppuration, especially liver abscess, were common features in this group of patients. Liver cirrhosis and/or alcoholism were the other frequent underlying conditions. 27 patients survived in the course of therapy. The prognostic factors with statistical significance were glucose ratio and cerebrospinal fluid (CSF) white blood cell (WBC) count. CONCLUSION This study showed the high incidence of diabetes mellitus (DM) among the adult patients with CASBM in Taiwan. K. pneumoniae was the most frequent causative pathogen. Bacteremia and focal suppuration, especially liver abscess, were common findings. The values of glucose ratio and CSF WBC count had a statistically significant influence on the prognosis of our patients.
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Affiliation(s)
- C R Huang
- Dept. of Neurology, Chang Gung Memorial Hospital-Kaohsiung, 123 Ta Pei Road, Niao Sung Hsiang, Kaohsiung Hsien 833, Taiwan
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Cimarusti CM, Applegate HE, Chang HW, Floyd DM, Koster WH, Slusarchyk WA, Young MG. Monobactams. The conversion of 6-APA to (S)-3-amino-2-oxoazetidine-1-sulfonic acid and its 3 (RS)-methoxy derivative. J Org Chem 2002. [DOI: 10.1021/jo00340a049] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Chang HW, Setser DW. Unimolecular Reaction and Collisional Deactivation of Chemically Activated 1,2-Difluoroethane Produced by Mercury Photosensitization of Chlorofluoromethane at 300 and 475°K. J Am Chem Soc 2002. [DOI: 10.1021/ja50001a022] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Setser DW, Chang HW, Perona MJ. Comparison of energy partitioning from three-centered processes. Bimolecular transfer and unimolecular elimination reactions. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100682a029] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gordon EM, Chang HW, Cimarusti CM, Toeplitz B, Gougoutas JZ. Sulfenyl transfer rearrangement of sulfenimines (thiooximes). A novel synthesis of 7.alpha.-methoxycephalosporins and 6.alpha.-methoxypenicillins. J Am Chem Soc 2002. [DOI: 10.1021/ja00525a038] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Koster WH, Zahler R, Chang HW, Cimarusti CM, Jacobs GA, Perri M. 2-Oxoazetidine-1-phosphonic acids: synthesis and transesterification. J Am Chem Soc 2002. [DOI: 10.1021/ja00349a084] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chang HW, Craig NL, Setser DW. Nonequilibrium unimolecular reactions and collisional deactivation of chemically activated fluoroethane and 1,1,1-trifluoroethane. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100651a002] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
The RecB subunit of the Escherichia coli RecBCD enzyme has both helicase and nuclease activities. The helicase function was localized to an N-terminal domain, whereas the nuclease activity was found in a C-terminal domain. Recent analysis has uncovered a group of proteins that have weak amino acid sequence similarity to the RecB nuclease domain and that are proposed to constitute a family of related proteins (Aravind, L., Walker, D. R., and Koonin, E. V. (1999) Nucleic Acids Res. 27, 1223-1242). One is the E. coli RecE protein (exonuclease VIII), an ATP-independent exonuclease that degrades the 5'-terminated strand of double-stranded DNA. We have made mutations in several residues of RecE that align with the critical residues of RecB, and we find that the mutations reduce or abolish the nuclease activity of RecE but do not affect the enzyme binding to linear double-stranded DNA. Proteolysis experiments with subtilisin show that a stable 34-kilodalton C-terminal domain that contains these critical residues has nuclease activity, whereas no stable proteolytic fragments accumulate from the N-terminal portion of RecE. These results show that RecE has a nuclease domain and active site that are similar to RecB, despite the very weak sequence similarity between the two proteins. These similarities support the hypothesis that the nuclease domains of the two proteins are evolutionarily related.
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Affiliation(s)
- H W Chang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA
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Abstract
BACKGROUND We analyzed the clinical features and therapeutic outcomes of adults with meningitis caused by viridans streptococci. PATIENTS AND METHODS 12 adult patients with meningitis caused by viridans streptococci were enrolled in this study. Clinical data were collected over a period of 15 years. RESULTS Of the 12 patients, 11 patients had community-acquired meningitis, while one had nosocomially acquired meningitis. 11 contracted the spontaneous form and one contracted the postneurosurgical form. All isolates were susceptible to penicillin. The portals of entry of infection were determined in all 12 patients; five patients had otopharyngeal infections with or without their being spread hematogenously. The infections in six patients were spread hematogenously, but one of them was spread hematogenously with endocarditis. One patient became infected after a craniotomy. The patients infected by viridans streptococci had a high incidence of focal suppuration and cerebral vasculitis but no deaths occurred. CONCLUSION Adult bacterial meningitis caused by viridans streptococci is not uncommon and otopharyngeal infection appears to be an important portal of entry. Clinical manifestations varied according to the different underlying conditions. The results of this study also demonstrate the high incidence of intracranial focal suppuration and cerebral vasculitis concomitant with meningitis. Penicillin remains the treatment of choice for patients with meningitis caused by viridans streptococci. Therapeutic outcome is favorable for patients who receive prompt treatment.
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Affiliation(s)
- C H Lu
- Dept. of Neurology, Chang Gung Memorial Hospital-Kaohsiung, Kaohsiung Hsien, Taiwan.
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Abstract
The purpose of this study was to evaluate refractive and anterior chamber depth changes after short-term dorzolamide use in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OH). This study was prospective and non-comparative and included 34 patients. Baseline refraction and anterior chamber depth were compared to the refraction and anterior chamber depth 14 days after commencing dorzolamide to determine if refraction or anterior chamber depth had been affected. Before dorzolamide use, the mean refractive error was -0.88 +/- 3.53 D (+/-SD). The mean refractive error was -0.94 +/- 3.65 D (+/-SD) two hours post-dose after 14 days of dorzolamide use, which was not significantly different (P = 0.50). The mean pre-treatment anterior chamber depth was 3.088 +/- 0.385 mm (+/-SD), which did not differ significantly from the post-treatment anterior chamber depth mean of 3.092 +/- 0.389 mm (+/-SD) (P = 0.88). The results of the study show that refraction and anterior chamber depth are not significantly altered by short-term dorzolamide use in patients with POAG and OH with no history of previous dorzolamide use.
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Affiliation(s)
- J C Tsai
- Department of Ophthalmology, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China.
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Abstract
BACKGROUND Our aim was to analyze the prognostic factors and therapeutic outcomes of adult tuberculous meningitis (TBM). PATIENTS AND METHODS Clinical data of 36 patients with adult TBM were retrospectively identified at our institution over a period of 5 years. RESULTS 36 adult TBM patients, 23 males and 13 females, aged 16-83 years, were included in this study. The 36 patients were also divided into three groups (stages I, II and III) according to the severity of TBM on admission. Therapeutic outcomes at 3 months were determined using a modified Barthel Index (BI). For the purpose of statistical analysis, the patients were divided into two groups: good outcome (BI > or = 12) and poor outcome (BI < 12). Positive cerebrospinal fluid (CSF) culture was found in 47% (17/36) of patients and isoniazid-resistant strains were found in 18% (3/17) of culture-proven TBM. We statistically compared clinical manifestations, CSF features and therapeutic results of the two patient groups. Significant prognostic factors included severity of TBM at the time of admission, the presence of headache, fever, hydrocephalus, high CSF protein concentration and high CSF lactate concentration. In stepwise logistic regression analysis, only the presence of hydrocephalus and severity of TBM on admission were strongly associated with therapeutic failure even after adjusting for other potentially confounding factors. CONCLUSION In Taiwan, TBM is an important public health issue and the emergence of resistant strains of this disease in recent years presents a therapeutic challenge. Because delay in diagnosis is directly related to poor outcome, early diagnosis and early treatment are essential for survival.
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Affiliation(s)
- C H Lu
- Dept. of Neurology, Chang Gung Memorial Hospital-Kaohsiung, Kaohsiung Hsien, Taiwan.
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Chi YS, Jong HG, Son KH, Chang HW, Kang SS, Kim HP. Effects of naturally occurring prenylated flavonoids on enzymes metabolizing arachidonic acid: cyclooxygenases and lipoxygenases. Biochem Pharmacol 2001; 62:1185-91. [PMID: 11705451 DOI: 10.1016/s0006-2952(01)00773-0] [Citation(s) in RCA: 176] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Prenylated flavonoids are chemical entities having an isoprenyl, a geranyl, a 1,1-dimethylallyl, and/or a lavandulyl moiety as part of their flavonoid backbone structure. In this study, the effects of 19 naturally occurring prenylated flavonoids, isolated from medicinal plants, on cyclooxygenase (COX)-1 and COX-2 and on 5-lipoxygenase (5-LOX) and 12-LOX were investigated using [14C]arachidonic acid as a substrate. The homogenates of bovine platelets and polymorphonuclear leukocytes were used as COX-1, 12-LOX, and 5-LOX enzyme sources; the homogenate of aspirin-pretreated lipopolysaccharide-induced RAW 264.7 cells was used for the COX-2 enzyme source. Among the 19 prenylated flavonoids, morusin, kuwanon C, sanggenon B, sanggenon D and kazinol B inhibited COX-2 activity (ic(50) = 73-100 microM), but the potencies were far less than that of NS-398 (ic(50) = 2.9 microM). In contrast, many prenylated flavonoids, such as kuraridin, kuwanon C and sophoraisoflavanone A, inhibited COX-1 activity. Of the COX-1 inhibiting prenylated flavonoids, kuraridin, kurarinone, and sophoraflavanone G, all having a C-8 lavandulyl moiety, showed potent activity (ic(50) = 0.1 to 1 microM) comparable to that of indomethacin (ic(50) = 0.7 microM). Most of the prenylated flavonoids tested inhibited 5-LOX activity with ic(50) values ranging from 0.09 to 100 microM. Of these, only kuwanon C, papyriflavonol A and sophoraflavanone G showed inhibitory activity against 12-LOX at low concentration ranges (ic(50) = 19-69 microM) comparable to that of NDGA (ic(50) = 2.6 microM). Our results suggest that the position and the nature of the prenyl substitution greatly influence in vitro biological activities of these molecules.
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Affiliation(s)
- Y S Chi
- College of Pharmacy, Kangwon National University, 200-701, Korea, Chunchon, South Korea
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Wu TL, Chang HW. Guiding mode expansion of a TE and TM transverse-mode integral equation for dielectric slab waveguides with an abrupt termination. J Opt Soc Am A Opt Image Sci Vis 2001; 18:2823-2832. [PMID: 11688873 DOI: 10.1364/josaa.18.002823] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We propose a rigorous transverse-mode integral equation formulation for analyzing TE and TM electromagnetic radiation fields on the facet of dielectric slab waveguides with an abrupt termination in free space. Both exact waveguide guiding modes and discretized radiation modes are included in the kernels of the integral equation. To reduce the size of the matrix that approximates the exact integral equation, we expand the unknown field at the junctions in terms of guiding modes of a selected waveguide with sufficiently large normalized frequency and core thickness. By direct matrix inversion, we obtain numerical solutions of the scattered fields at the junctions. Our method can be used to study the field distribution as well as the energy reflection and transmission coefficients of dielectric waveguides with multiple step discontinuities.
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Affiliation(s)
- T L Wu
- Institute of Electro-Optical Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan
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Chang HW, Lee HJ. Inconsistency in the expression of locomotor and ERG circadian rhythms in the German cockroach, Blattella germanica (L.). Arch Insect Biochem Physiol 2001; 48:155-166. [PMID: 11673845 DOI: 10.1002/arch.1068] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
ERG recordings from German cockroaches showed that the amplitude of light-evoked responses have a circadian rhythmicity in adult males that coincided with the locomotor circadian rhythm. The peak of the response occurred during the subjective night, and the circadian period was less than 24 h under DD condition. In contrast, although the locomotor circadian rhythm was masked by the development of ovaries and pregnancy in females, their visual responses displayed circadian rhythmicity. This inconsistency in expression of locomotor and visual sensitivity circadian rhythms in females implied separate pacemakers for these two overt rhythms. After severing the optic nerves, changes in ERG amplitude of the operated cockroaches still displayed a circadian rhythm under DD condition, demonstrating that the visual sensitive pacemaker was located in the eye and independent from the locomotor pacemaker.
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Affiliation(s)
- H W Chang
- Department of Entomology, National Taiwan University, Taipei, Taiwan
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Abstract
Thirty-eight patients with streptococcal meningitis, aged 17-75 years, have been identified over a period of 13.5 years. Among these 38 patients, 35 had community-acquired infections, and the other three had nosocomial infections. Twelve of the 38 patients were found to have postneurosurgical forms and 26 to have spontaneous forms. These 38 cases of streptococci included Streptococcus (S.) pneumoniae in 19 cases, viridans group streptococci in 13, non-A, non-B, and non-D streptococci in three, Group D streptococci in one, and Group B streptococci (S. agalactiae) in two. Although one case was found to have penicillin-resistant S. pneumoniae PRSP in 1994, multi-antibiotic resistant strains were rare in this study. Therapeutic outcomes varied according to the different species of streptococci. In this study, the overall mortality rate was 34%. In the multiple logistic regression analysis, only initial consciousness level and the presence of seizure were strongly associated with the mortality rate even after other potentially confounding factors were adjusted for. Early diagnosis and the use of appropriate antibiotics are essential for survival.
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Affiliation(s)
- C H Lu
- Department of Neurology, Chang Gung Memorial Hospital-Kaohsiung, 123, Ta Pei Road, Niao Sung Hsiang, Kaohsiung Hsien, Taiwan, ROC.
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Chang WN, Lu CH, Wu JJ, Chang HW, Tsai YC, Chen FT, Chien CC. Staphylococcus aureus meningitis in adults: a clinical comparison of infections caused by methicillin-resistant and methicillin-sensitive strains. Infection 2001; 29:245-50. [PMID: 11688900 DOI: 10.1007/s15010-001-1092-z] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND This study was undertaken to compare the clinical characteristics of adult methicillin-sensitive Staphylococcus aureus (MSSA) meningitis and adult methicillin-resistant S. aureus (MRSA) meningitis. PATIENTS AND METHODS The clinical characteristics and therapeutic outcomes of 19 adult patients with S. aureus meningitis, including eight with MSSA infections and 11 with MRSA infections, were analyzed. A comparison was made between the clinical data of the patients with MSSA infections and those with MRSA infections. RESULTS Before the end of 1995, MSSA infection was involved in all the adult patients with S. aureus meningitis but thereafter, MRSA infection was involved in 79% of the cases. The clinical characteristics found in patients with MSSA infection included underlying medical disorders (75%), community-acquired infection (75%) and mortality rate (13%). The clinical characteristics found in patients with MRSA infection included post-neurosurgical states (91%), nosocomial infections (100%), men outnumbering women (8:3), hydrocephalus (36%) and mortality rate (56%). Comparative study between the patient groups (hematogenous and post-neurosurgical) showed that only the mode of acquisition of infection had statistical significance. CONCLUSIONS This study showed an increase in MRSA infections in adult S. aureus meningitis in recent years. The clinical characteristics of patients with MSSA and MRSA meningitis were different. Community-acquired infection was common in hematogenous S. aureus meningitis, while nosocomial infection was common in post-neurosurgical S. aureus meningitis. Vancomycin should be considered as one of the drugs of choice for initial therapy of adult bacterial meningitis, especially in post-neurosurgical patients.
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Affiliation(s)
- W N Chang
- Dept. of Neurology, Chang Gung Memorial Hospital, Kaohsiung Hsien, Taiwan.
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Yip HK, Wu CJ, Chen MC, Chang HW, Hsieh KY, Hang CL, Fu M. Effect of primary angioplasty on total or subtotal left main occlusion: analysis of incidence, clinical features, outcomes, and prognostic determinants. Chest 2001; 120:1212-7. [PMID: 11591563 DOI: 10.1378/chest.120.4.1212] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Although acute left main coronary artery (LMCA) occlusion is a rare clinical entity, it carries a very high mortality rate. The purposes of this study were to evaluate the effect of primary angioplasty for a severely obstructed or totally occluded LMCA, and to determine the incidence, clinical features, outcome, and prognostic determinants in this clinical setting. MATERIALS AND METHODS Between May 1993 and July 2000, a total of 740 patients with acute myocardial infarction underwent primary angioplasty in our hospital. Eighteen of 740 patients (2.4%) with a severely obstructed or totally occluded LMCA constituted the population of this study. RESULTS Seventeen of 18 patients (94.4%) experienced pulmonary edema (including 14 patients in cardiogenic shock). Six patients (33.3%) sustained sudden death due to malignant ventricular tachyarrhythmias. Coronary angiography showed that there were variable grade flow of intercoronary collaterals in 12 patients (66.7%), a totally occluded LMCA in 8 patients (44.4%), an incompletely occluded LMCA in 10 patients (55.6%), and a dominant right coronary artery (RCA) in 16 patients (88.9%). Primary angioplasty of the LMCA was performed with a 72.2% procedural success rate. Four patients (22.2%) received coronary artery bypass surgery after angioplasty. Six patients (33.3%) died in the hospital. Two patients died after discharge. Ten of 18 patients (55.6%) survived in long-term follow-up (mean +/- SD, 44 +/- 14 months). Those patients who survived to be discharged had significantly higher combined coexisting incidence of intercoronary collaterals, dominant RCA, and incompletely occluded LMCA (100% vs 0.0%, p = 0.0006) than those patients who died in the hospital. CONCLUSIONS Acute obstructive LMCA disease generally presented as pulmonary edema, cardiogenic shock, or sudden death. Only those who had combined coexistence of intercoronary collaterals, a dominant RCA, and an incompletely occluded LMCA could survive to be discharged. Our experience suggests that primary LMCA angioplasty is a feasible and effective procedure, and it may save lives in this clinical setting.
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Affiliation(s)
- H K Yip
- Division of Cardiology, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
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Chen YC, Chang HW. Clinical characteristics of Behçet's disease in southern Taiwan. J Microbiol Immunol Infect 2001; 34:207-10. [PMID: 11605813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
A total of 22 patients were found to have Behçet's disease during the period from 1991 through 1999 in the Chang Gung Memorial Hospital in Kaohsiung, Taiwan. Diagnosis of Behçet's disease was made according to the criteria proposed by the International Study Group for Behçet's Disease. Oral lesions were found in all patients, ocular lesions in 55% of patients, genital lesions in 55%, skin lesions in 90.9%, pathergy reaction in 22.7%, arthritis in 31.8%, gastrointestinal involvement in 31.8%, involvement of the central nervous system in 27.2%, and thrombophlebitis in 18%. The mean age was 35.5 years with a biphasic age distribution. The clinical characteristics of patients in this series were different from patients in other Asian countries, which suggests that geographic and genetic factors are important in the pathogenesis of the disease.
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Affiliation(s)
- Y C Chen
- Department of Rheumatology, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, ROC
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Chen MC, Chang JP, Guo GB, Chang HW. Atrial size reduction as a predictor of the success of radiofrequency maze procedure for chronic atrial fibrillation in patients undergoing concomitant valvular surgery. J Cardiovasc Electrophysiol 2001; 12:867-74. [PMID: 11513435 DOI: 10.1046/j.1540-8167.2001.00867.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Previous studies showed that the surgical maze procedure can restore sinus rhythm and atrial transport function in patients with chronic atrial fibrillation (AF). However, no previous studies discussed the association of atrial size reduction and the success of sinus conversion by the radiofrequency (RF) maze procedure for chronic AF. METHODS AND RESULTS A total of 119 chronic AF patients undergoing valvular operations were included in this study. Sixty-one patients received RF and cryoablation to create lesions in both atria to simulate the surgical maze II or III procedure (RF maze II or RF maze III; 13 patients, group 1) or a modified maze pattern (RF maze "IV"; 48 patients, group 2). The other 58 patients who underwent valvular operations alone without the maze procedure served as control (group 3). At 3-month follow-up after operation, sinus rhythm was restored in 73%, 81%, and 11% of patients in groups 1, 2 and 3, respectively. Preoperative left and right atrial sizes were not statistically significant predictors of sinus conversion by the RF maze procedure. However, as a result of postoperative reduction of atrial sizes, postoperative left atrial diameter was significantly smaller in patients who had sinus conversion by the RF maze procedure than in patients who did not regain sinus rhythm (45.0+/-7.0 mm vs 51.0+/-8.0 mm; P = 0.03). Postoperative right atrial area of patients who had sinus conversion by the RF maze procedure also was significantly smaller than that of patients who did not regain sinus rhythm (18.1+/-4.4 cm2 vs 28.5+/-8.2 cm2; P = 0.008). CONCLUSION Atrial size reduction appears to predict the success of sinus conversion with the RF maze procedure used in conjunction with valvular surgery.
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Affiliation(s)
- M C Chen
- Department of Medicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
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Abstract
PURPOSE To investigate the correlation between the clinical pictures and the specular microscopic findings in patients with iridocorneal endothelial (ICE) syndrome. METHODS The records of 15 patients with ICE syndrome who presented at the National Taiwan University Hospital between 1993 and 1996 were examined. The medical history, clinical pictures of the cornea, iris and anterior chamber angle, intraocular pressure, specular microscopic findings, and the correlation between clinical and specular microscopic findings were assessed. RESULTS Endothelial changes in specular micrographs were found in all the patients, even in those patients with minimal angle involvement by peripheral anterior synechiae. Corneal decompensation resulting in corneal edema and bullae formation was the main cause of visual impairment. Neither ICE grading nor endothelial cell density correlated with corneal edema or intraocular pressure, but they correlated with the angle involvement in ICE syndrome. The intraocular pressure was difficult to control in 8 of these patients, even after treatment with anti-glaucoma agents and trabeculectomy, especially in the patients with Cogan-Reese syndrome. CONCLUSION Although specular microscopy provides an invaluable method for the diagnosis of ICE syndrome, it is not a reliable tool for predicting prognosis. Close follow-up of intraocular pressure and early detection of glaucoma are important steps to preserve visual functions in patients with ICE syndrome.
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Affiliation(s)
- Y K Liu
- Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan
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Chen HJ, Cho CL, Liang CL, Chen L, Chang HW, Lu K, Lee TC. Differential telomerase expression and telomere length in primary intracranial tumors. Chang Gung Med J 2001; 24:352-60. [PMID: 11512366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
BACKGROUND Telomerase activity and telomere length have been shown to be involved in controlling cell proliferation and regulating cell senescence. The authors examined telomerase activity and telomere length in intracranial tumors to determine the clinicopathological behavior of primary intracranial tumors with respect to telomerase expression and alteration of telomere length. METHODS Telomerase activity was examined in 139 brain tumor samples. Telomere length was examined in 138 of the 139 samples. These tumors included 61 meningiomas, 27 schwannomas, 19 high-grade neuroepithelial tumors, and 32 low-grade neuroepithelial tumors. Telomerase activity was measured with a telomerase polymerase chain reaction, enzyme-linked immunosolvent assay kit. Telomere length was examined by Southern blot analysis for the terminal restriction fragment length. RESULTS Telomerase activity was detected in 39.2% (20/51) of the neuroepithelial tumors. Detection rates were 47.4% (9/19) for anaplastic astrocytomas and glioblastomas and 34.4% (11/32) for low-grade neuroepithelial tumors. However, detectable telomerase activity was found in 30.8% (4/13) of atypical or malignant meningiomas, but was not detected in any schwannomas. There was a highly significant difference in the telomerase detection rate in neuroepithelial or non-neuroepithelial tumors (p = 0.001). Telomere elongation was found in 11.7% (7/60) of all meningiomas, 46.1% (6/13) of atypical or malignant meningiomas, and 14.8% (4/27) of schwannomas. Elongation of telomere length was detected in 12.6% (11/87) of the cases and 23.5% (12/51) in neuroepithelial tumors. This difference was also significant (p < 0.05). Telomere length was reduced in the majority, (75%, 3/4) of malignant or atypical meningiomas with detectable telomerase activity, but only 45% (9/20) of the neuroepithelial tumors. CONCLUSION These results indicate that telomerase activation may be a critical step in the pathogenesis of intracranial tumors. Telomere length elongation also indicates a high potential for malignant behavior in these tumors.
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Affiliation(s)
- H J Chen
- Department of Neurosurgery, Chang Gung Memorial Hospital, 123, Tao-Pei Road, Niaosung, Kaohsiung, Taiwan, R.O.C.
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Liliang PC, Liang CL, Lu CH, Chang HW, Cheng CH, Lee TC, Chen HJ. Hypertensive caudate hemorrhage prognostic predictor, outcome, and role of external ventricular drainage. Stroke 2001; 32:1195-200. [PMID: 11340233 DOI: 10.1161/01.str.32.5.1195] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The purpose of the present study was to analyze the outcome and outcome predictors of caudate hemorrhage and role of external ventricular drainage in acute hydrocephalus. METHODS Clinical data from 36 consecutive patients with hypertensive caudate hemorrhage was used in the present study. Age, gender, volume of parenchymal hematoma, hematoma in the internal capsule, initial Glasgow Coma Scale (GCS), hydrocephalus, severity of intraventricular hemorrhage, and hemorrhagic dilatation of the fourth ventricle were analyzed for effect on outcome. Effect of external ventricle drainage for hydrocephalus was evaluated by comparing preoperative and postoperative GCS scores. RESULTS By univariate analyses, poor outcome was associated with a poor initial GCS score (P=0.016), hydrocephalus (P<0.001), intraventricular hemorrhage severity (P<0.01), and hemorrhagic dilatation of the fourth ventricle (P=0.02). By multivariate analysis, stepwise logistic regression revealed that hydrocephalus was the only independent prognostic factor for poor outcome (P<0.001). Postoperative 48-hour GCS score was better than the preoperative score by use of paired-sample t test (P<0.001). CONCLUSIONS Hydrocephalus is the most important predictor of poor outcome. External ventricular drainage response for hydrocephalus was good in the present study, whereas an early decision should be made regarding preoperative neurological condition.
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Affiliation(s)
- P C Liliang
- Departments of Neurosurgery, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Niaosung Hsiang, Kaohsiung Hsien, Taiwan
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Abstract
Twenty-eight patients with cerebral infarction secondary to chronic meningitis were retrospectively identified at our institution over a period of 5 years. They accounted for 47% (17/36) of tuberculous meningitis (TBM) and 32% (11/34) of cryptococcal meningitis cases. Single infarctions were found in 15 patients and multiple infarctions in 13. The distribution of single infarctions was: basal ganglia 7; internal capsule 3; thalamus 1; cerebellum 1; and cortical infarct 3. Therapeutic outcomes at 3 months were determined using a modified Barthel INDEX: At follow-up of 3 months or more, 10 had good outcomes while the other 18 had poor outcomes. The 18 with poor outcomes included six who died, and 12 who had severe neurological sequelae. TBM and cryptococcal meningitis shared similar clinical features, both being frequently associated with other neurological complications, including hydrocephalus, cranial nerve palsy, and seizures in our patients. However, extracranial involvement, such as spinal and pulmonary involvement, was more commonly found in TBM patients. Cerebral infarction can occur in both the acute stage and later stages of treatment. Mortality and morbidity are high, and early diagnosis and appropriate antimicrobial treatment are essential. If hydrocephalus is demonstrated, early ventricular decompression is needed to prevent further cerebral ischaemia.
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Affiliation(s)
- S H Lan
- Departments of Neurology, Chang Gung Memorial Hospital Kaohsiung, Kaohsiung, Taiwan
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Yip HK, Wu CJ, Chang HW, Chen MC, Hang CL, Fang CY, Hsieh YK, Yang CH, Yeh KH, Fu M. Comparison of impact of primary percutaneous transluminal coronary angioplasty and primary stenting on short-term mortality in patients with cardiogenic shock and evaluation of prognostic determinants. Am J Cardiol 2001; 87:1184-8; A4. [PMID: 11356395 DOI: 10.1016/s0002-9149(01)01491-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- H K Yip
- Division of Cardiology, Chang Gung Memorial Hospital, Kaohsiung, Taiwan
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Abstract
A new prenylated flavonol, papyriflavonol A, was isolated from the root barks of Broussonetia papyrifera. The structure of this compound was elucidated as 5,7,3',4'-tetrahydroxy-6,5'-di-(gamma,gamma-dimethylallyl)-flavonol (1) by spectroscopic analysis.
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Affiliation(s)
- K H Son
- Department of Food and Nutrition, Andong National University, 760-749, Andong, South Korea.
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Abstract
OBJECTIVE To determine the wrist angle that produces the least compression to the median nerve and to evaluate the usefulness of sonography in determining the optimal position. DESIGN Seventeen wrists of 17 healthy volunteers received dynamic, high-frequency (8 MHz), high-resolution sonography with the wrist splinted at various positions: 15 degrees of flexion, neutral position, and 15 degrees and 30 degrees of extension. The morphologic changes of the median nerve were evaluated with the wrist positioned at various angles. RESULTS The neutral position caused significantly lower compression of the median nerve than it did in the other positions. However, in some cases, the lowest pressure was found when the wrist was fixed in 15 degrees of flexion or 15 degrees of extension. Because median nerve compression may decrease the anteroposterior diameter, increase the transverse diameter, and decrease the cross-sectional area, greater anteroposterior diameter, lower flattening ratio (transverse diameter/anteroposterior diameter), and greater cross-sectional area were considered to indicate lower median nerve compression. CONCLUSIONS Neutral position of the wrist is the best position with the least median nerve compression in most individuals. However, the optimal position may vary from person to person. Sonographic examination can help to determine the splint position that results in the lowest median nerve compression.
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Affiliation(s)
- M H Kuo
- Department of Physical Medicine, Chang Gung Memorial Hospital, Kaosiung, Taiwan
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Abstract
OBJECTIVES The independent predictors of aphasia outcome for patients with left basal ganglia hemorrhage were evaluated. PATIENTS AND METHODS We included 140 patients of 1,036 patients with spontaneous intracerebral hemorrhage admitted to our hospital from January 1993 through December 1997. Aphasia was assessed using the aphasia scale of the Scandinavian stroke scale. Univariate and step-wise logistic regression analyses were performed to assess the relationships between the initial aphasia score, age, gender, blood volume, locations of hematoma and aphasia outcome. RESULTS Step-wise logistic regression analysis revealed that the following two factors were independently associated with the final aphasia outcome: initial aphasia score (P < 0.0001) and location of hematoma involving the posterior limb of the internal capsule (P = 0.004). CONCLUSIONS A particularly high likelihood of poor aphasia outcomes of patients with left basal ganglia hemorrhage are predicted in those who have poor initial aphasia score and whose brain computed tomography shows the hematoma involves the posterior limb of the internal capsule.
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Affiliation(s)
- C L Liang
- Department of Neurosurgery, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Taiwan
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Abstract
A mixture of cerebrosides, called poke-weed cerebrosides, was purified from Phytolaccae Radix (Phytolaccaceae) and characterized as 1-O-beta-D-glucopyranosides of phytosphingosine type ceramides comprised of a common long chain base (2S,3S,4R,8Z)-2-amino-8-octadecene-1,3,4-triol and fatty acids. The fatty acyl chain of ceramide moieties was determined as (2R)-2-hydroxypentacosanoic acid, (2R)-2-hydroxylignoceric acid, (2R)-2-hydroxytricosanoic acid, (2R)-2-hydroxybehenic acid, (2R)-2-hydroxypalmitic acid, and palmitic acid. The pokeweed cerebroside inhibited the cyclooxygenase-2 dependent phase of prostaglandin D2 generation in bone marrow-derived mast cells in a concentration dependent manner with an IC50 of 6.2 microg/ml.
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Affiliation(s)
- S S Kang
- Natural Products Research Institute, Seoul National University, Korea.
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Huang FJ, Chang SY, Tsai MY, Kung FT, Wu JF, Chang HW. Determination of the efficiency of controlled ovarian hyperstimulation in the gonadotropin-releasing hormone agonist-suppression cycle using the initial follicle count during gonadotropin stimulation. J Assist Reprod Genet 2001; 18:91-6. [PMID: 11285987 PMCID: PMC3455557 DOI: 10.1023/a:1026582608645] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE Our purpose was to evaluate the relationship between the initial follicle count during gonadotropin stimulation after gonadotropin-releasing hormone (GnRH) agonist suppression and the efficiency of controlled ovarian hyperstimulation (COH) in patients receiving treatment with assisted reproductive technologies (ARTs). METHODS A total of 338 COH procedures in 291 couples was performed with cycles that reached the stage of oocyte retrieval. The ovarian antral follicle number was measured using transvaginal ultrasonography at the folliculometry during gonadotropin stimulation by GnRH agonist suppression in patients undergoing ARTs. Controlled ovarian hyperstimulation was accomplished using GnRH agonist down-regulation combined with FSH and menotropin stimulation. The characteristics of oocytes after retrieval and embryos after in vitro culture and the pregnancy rates were assessed. RESULTS The procedures performed included 195 ET cycles, 129 TET cycles, and 14 incomplete cycles. The treatment cycles were divided into four categories according to the antral follicle number (i.e., < or = 5, 6-10, 11-15, and > or = 16) at the first folliculometry to evaluate the influence of various factors. The antral follicle count correlated significantly with the patient age, dosage of gonadotropins, serum estradiol concentration, number of antral follicles (> or = 13 mm) while receiving hCG injections, number of oocytes retrieved, and, later, number of embryos transferred. There was a trend toward an increasing number of pregnancies per cycle as the number of antral follicles increased (14.7, 26.5, 44, and 45%, respectively). CONCLUSIONS We were able to predict the efficiency of COH and outcome of ARTs based on the follicle count during the first folliculometry during gonadotropin stimulation after GnRH agonist suppression. The results of the folliculometry significantly predicted the ovarian response to COH and the outcome of ARTs in the current treatment cycle.
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Affiliation(s)
- F J Huang
- Department of Obstetrics and Gynaecology, Chang-Gung Memorial Hospital, Kaohsiung County, Taiwan.
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Abstract
Atrial fibrillation, the most common chronic arrhythmia, results in an increased risk of stroke. Anticoagulation therapy can reduce this risk, but appears to be underused. The objective of this study was to examine the use of warfarin and prevalence of stroke in patients with rheumatic, nonrheumatic valvular and nonvalvular atrial fibrillation. Between January 1993 and December 1998, 457 chronic atrial fibrillation patients with continuous follow-up in our hospital were identified as having rheumatic heart disease (n = 114): nonrheumatic valvular disease (n = 65); or nonvalvular disease (n = 278). Warfarin was used less often in patients with nonrheumatic valvular (16.7%) and nonvalvular diseases (20.1%) than in those with rheumatic heart disease (81.6%, p < 0.001). In contrast, the prevalence of stroke among patients with nonvalvular disease was 40.3% which was similar to the 33.3% found in patients with rheumatic heart disease but significantly higher than the 24.6% found in patients with nonrheumatic valvular disease (p < 0.05). A history of stroke did not alter the trend of use of warfarin among the three groups of patients. Only 20.6% of patients on warfarin received monthly monitoring of prothrombin time. In conclusion, the anticoagulation therapy in our patients with chronic atrial fibrillation, regardless of their associated valvular diseases, is significantly underutilized. This underuse could account for a high prevalence of stroke. This risk of stroke, however, is less in patients with nonrheumatic valvular discase than in those with nonvalvular atrial fibrillation.
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Affiliation(s)
- G B Guo
- Department of Internal Medicine, Chang Gung Memorial Hospital, National Sun Yat-Sen University, Kaohsiung, Taiwan, Republic of China
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Abstract
In two investigative phases over a 13.5-year study period (January 1986-June 1999), 202 adult patients with culture-proven bacterial meningitis were enrolled in this study. In order to determine the epidemiologic trend, prognostic factors and therapeutic results for this disease. Klebsiella pneumoniae (K. pneumoniae), Pseudomonas aeruginosa, and Streptococcus pneumoniae were the three most commonly revealed pathogens, accounting for about 48% of the episodes. Although there was a change in relative frequency for the pathogens, K. pneumoniae remained the most prevalent during the two periods studied (January 1986-December 1992 and January 1993-June 1999). Multiantibiotic resistant strains have been in evidence since their appearance in 1994, with most of our patients acquiring their infection nosocomially. The overall mortality rates during the two periods were 40% and 34%, respectively. In stepwise logistic regression analysis, only initial conscious level, appropriate antibiotic therapy and septic shock were independently associated with mortality, after adjustment for other potentially confounding factors. Initial empirical antibiotics with both third-generation cephalosporin and penicillin G, should be considered for the majority of meningitis cases resulting from infection with Gram-negative bacilli and streptococcal species. Besides the evolution of newer pathogens, there has been increasing incidence for nosocomially acquired bacterial meningitis for patients postneurosurgery, with the emergence of resistant strains presenting a therapeutic challenge in recent years. Vancomycin and imipenem/cilastatin should be considered as the initial empirical antibiotics of choice for the treatment of this special group of patients.
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Affiliation(s)
- C H Lu
- Department of Neurology, Chang Gung Memorial Hospital, 123, Ta Pei Road, Niao Sung Hsiang, Kaohsiung Hsien, Taiwan.
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