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Oh GS, Pae HO, Choi BM, Jeong S, Oh H, Oh CS, Rho YD, Kim DH, Shin MK, Chung HT. Inhibitory effects of the root cortex of Paeonia suffruticosa on interleukin-8 and macrophage chemoattractant protein-1 secretions in U937 cells. JOURNAL OF ETHNOPHARMACOLOGY 2003; 84:85-89. [PMID: 12499080 DOI: 10.1016/s0378-8741(02)00285-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In an effort to elucidate the mechanism of the anti-inflammatory effect of mudanpi, the root cortex of Paeonia suffruticosa Andrews (Ranunculaceae), we determined the effects of the methanolic extract of mudanpi (MEM) on the secretions of interleukin (IL)-8, a major mediator of acute neutrophil-mediated inflammation, and macrophage chemoattractant protein (MCP)-1, a major mediator of chronic macrophage-mediated inflammation, in human monocytic U937 cells stimulated with phorbol myristate acetate (PMA). MEM significantly inhibited PMA-induced secretions of IL-8 and MCP-1 proteins in a dose-dependent manner. The inhibition of these chemokines by MEM was due to its suppression of IL-8 and MCP-1 genes. In addition, 1,2,3,4,6-penta-O-galloyl-beta-D-glucose, one of major constituents isolated from MEM, inhibited PMA-induced secretions of IL-8 and MCP-1 proteins by its suppression of IL-8 and MCP-1 genes. Thus, one possible anti-inflammatory mechanism of mudanpi, an anti-inflammatory Chinese crude drug, may be to inhibit the secretions of inflammatory chemokines.
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102
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An SJ, Pae HO, Oh GS, Choi BM, Jeong S, Jang SI, Oh H, Kwon TO, Song CE, Chung HT. Inhibition of TNF-alpha, IL-1beta, and IL-6 productions and NF-kappa B activation in lipopolysaccharide-activated RAW 264.7 macrophages by catalposide, an iridoid glycoside isolated from Catalpa ovata G. Don (Bignoniaceae). Int Immunopharmacol 2002; 2:1173-81. [PMID: 12349954 DOI: 10.1016/s1567-5769(02)00085-1] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Catalposide, the major iridoid glycoside isolated from the stem bark of Catalpa ovata G. Don (Bignoniaceae), was found to inhibit the productions of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6), and the activation of nuclear factor kappaB (NF-kappaB) in RAW 264.7 macrophages activated with lipopolysaccharide (LPS). Catalposide also inhibited the expressions of TNF-alpha, IL-1beta, and IL-6 genes and the nuclear translocation of p65 subunit of NF-kappaB in LPS-activated RAW 264.7 cells. Flow cytometric analysis revealed that catalposide suppressed the binding of FITC-conjugated LPS to CD14 on the surface of cells, probably resulting in the inhibitory effects on TNF-alpha, IL-1beta, and IL-6 productions and NF-kappaB activation. These findings suggest that catalposide could be an attractive candidate for adjunctive therapy in gram-negative bacterial infections.
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103
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Lantos I, Oh H, Razgaitis C, Loev B. Synthesis of 6-substituted-2,3-dihydro-1H-imidazo[1,5-b]pyrazoles. J Org Chem 2002. [DOI: 10.1021/jo00419a027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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104
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Abstract
We describe here two cases of Cryptococcus neoformans var. gattii meningitis that occurred in Singapore. This variety of Cryptococcus neoformans differs from the more widely known C. n. var. neoformans in its ecology and epidemiology. Infections with this variety are still rare in Singapore.
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Koh TH, Tan AL, Lo YL, Oh H. Cryptococcus neoformans var. gattii meningitis in Singapore. Med Mycol 2002. [DOI: 10.1080/714031091] [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] Open
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106
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Pae HO, Oh GS, Kim NY, Shin MK, Lee HS, Yun YG, Oh H, Kim YM, Chung HT. Roles of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase in apoptosis of human monoblastic leukemia U937 cells by lectin-II isolated from Korean mistletoe. IN VITRO & MOLECULAR TOXICOLOGY 2002; 14:99-106. [PMID: 11690563 DOI: 10.1089/10979330152560496] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The mitogen-activated protein kinase (MAPK) family members have been implicated in cell survival. We have previously demonstrated that cytotoxic lectin-II isolated from Korean mistletoe induces apoptotic cell death in the human monoblastic leukemia cell line, U937, via the activation of the stress-activated protein kinases/c-Jun N-terminal kinase (SAPK/JNK). In the present study, the roles of extracellular signal-regulated kinases (ERK1/2) and p38 MAPK in lectin-II-induced apoptosis have been investigated. Treatment of U937 cells with lectin-II resulted in apoptotic DNA fragmentation, which was preceded by the activation of ERK1/2, p38 MAPK and SAPK/JNK. This lectin-II-induced DNA fragmentation was significantly enhanced when ERK1/2 activation was selectively inhibited by PD098059. 12-O-tetradecanoylphorbol-13-acetate, which stimulates ERK activity in U937 cells, markedly reduced lectin-II-induced DNA fragmentation. Inhibition of p38 MAPK activity with p38-specific inhibitor, SB203580, partially inhibited lectin-II-induced DNA fragmentation. These results suggest that ERK1/2 and p38 MAPK may have opposite effects on cell survival in response to cytotoxic mistletoe lectin-II, which may contribute to the modulation of lectin-II-mediated cytotoxic activity.
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107
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Oh GS, Pae HO, Oh H, Hong SG, Kim IK, Chai KY, Yun YG, Kwon TO, Chung HT. In vitro anti-proliferative effect of 1,2,3,4,6-penta-O-galloyl-beta-D-glucose on human hepatocellular carcinoma cell line, SK-HEP-1 cells. Cancer Lett 2001; 174:17-24. [PMID: 11675148 DOI: 10.1016/s0304-3835(01)00680-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The root of Paeonia suffruticosa ANDREWS is an important Chinese crude drug used in many traditional prescriptions. 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG), a major component of this crude drug, was found to exhibit in vitro growth-inhibiting effect on human hepatocellular carcinoma cell line, SK-HEP-1 cells. The growth-inhibitory effect was related to the ability of PGG not only to cause a G(0)/G(1) phase arrest but also to suppress the activation of nuclear factor-kappa B. Neither apoptosis nor necrosis was observed in the cells treated with PGG. These findings suggest that PGG could be a candidate for developing a low-toxic anticancer agent.
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108
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Lee M, Kim JQ, Kim J, Oh H, Park M. Studies on the plasma lipid profiles, and LCAT and CETP activities according to hyperlipoproteinemia phenotypes (HLP). Atherosclerosis 2001; 159:381-9. [PMID: 11730818 DOI: 10.1016/s0021-9150(01)00513-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hyperlipoproteinemia phenotypes (HLP), one of genetic disorders with an estimated prevalence of 0.5-2% in the general population, is responsible for 10% of premature CHD. After first screening with the high cholesterol (>6.47 mM/l) and triglyceride (TG) (>2.6 mM/l) levels without medication, subjects were typed for HLP classification. Differential metabolic effects of HLP types on plasma lipid profiles and the reverse cholesterol transport system (RCT) were studied in 196 HLP types (91.2%) and 19 non-HLP (8.8%). A total of 45% of subjects had primary HLP and the others had NIDDM (10.7%), hypertension (9.3%) and other chronic diseases. Type IV HLP (58.6%) was most predominant and Types IIa, IIb, III and V comprised 16.7, 12.1, 2.3 and 1.4% of the HLP. Type I was not found. Plasma lipids excluding apo A-I and Lp(a) were significantly different among HLP compared to non-HLP (P<0.001). Since Type V and III impact the clearance of TG-riched lipoproteins, TG and VLDL-C levels were higher in V and III. TG and LDL-C were higher in Type II than those in the others because of defect of LDL receptors. LCAT activity, lower in Type III and Type IV and highest in Type V, was highly associated with plasma free cholesterol levels and the ratio of apoB/apoA and LDL/HDL. CETP activity was highest in Type V due to high VLDL-C and TG and low HDL-C. The ratio of LCAT/CETP was not different among HLP types but was significantly lower in HLP than in non-HLP. CETP increased 2-3 times as well as LCAT decreased among HLP patients compared to non-HLP. We conclude non-HLP subjects with high cholesterol and TG levels do not always mean high risk of CHD and the intervention effects of HLP types would lead to impose the risk of CHD by the impact of RCT.
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Hudson AJ, Naumkin FY, Oh H, Polanyi JC, Raspopov SA. Dynamics of harpooning studied by transition state spectroscopy. Part III. Li...FCH3. Faraday Discuss 2001:191-207; discussion 233-45. [PMID: 11605266 DOI: 10.1039/b009877i] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Van der Waals complex Li...FCH3 has been formed in a crossed molecular beam apparatus. The transition state (TS) for the reaction Li*(2p 2P) + FCH3-->LiF + CH3 was accessed at various configurations by laser-excitation of the Li...FCH3 complex by tunable visible radiation, lambda 1. Photoinduced depletion of the complex by excitation to this TS was found to occur across a broad range of lambda 1 from 570 to 850 nm. This 'action spectrum' consisted of two broad regions located to either side of the atomic transition line of Li (2p 2P<--2s 2S). The first region, between 700 and 850 nm, was dominated by sharp maxima in the depletion intensity. A broad peak with weakly-resolved structure characterized the second region, between 570 and 680 nm. These findings were interpreted by means of high-level ab initio calculations of the potential-energy surfaces in the TS region. The peaks in the photodepletion spectrum were assigned to specific electronic transitions, their shapes and intensities being explained in terms of calculated transition-dipole moments and rovibrational wavefunctions.
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110
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Kim SH, Lee JH, Oh H, Kim SR, Lee CS, Jo SK, Kim TH, Lee YS. Dependence of malformation upon gestational age and exposed dose of gamma radiation. JOURNAL OF RADIATION RESEARCH 2001; 42:255-264. [PMID: 11840642 DOI: 10.1269/jrr.42.255] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In order to evaluate the importance of gestational age and the dose-incidence relationship by gamma radiation, pregnant ICR mice at gestational days from 2.5 to 15.5 days post-coitus (p.c.) were exposed to a single dose of 2.0 Gy and also at day 11.5 after conception, which was the most sensitive stage for the induction of major congenital malformations. The animals were sacrificed on day 18 of gestation and the fetuses were examined for mortality, growth retardation, changes in head size and other morphological abnormalities. The only demonstrable effect of irradiation during the pre-implantation period was an increase in prenatal mortality. Resorptions were maximal on exposure at day 2.5 after conception. The pre-implantation irradiated embryos which survived did not show any major fetal abnormalities. A small head, growth retardation, a cleft palate, dilatation of the cerebral ventricle, a renal pelvis, and abnormalities of the extremities and tail after exposure were prominent during the organogenesis period, especially on day 11.5 of gestation. As for the dose-incidence relationship, the incidence of a small head, growth-retarded fetuses, a cleft palate, dilatation of cerebral ventricle and abnormalities of the extremities in live fetuses rose as the radiation dose increased. The result indicated that the late period of organogenesis in the development of the brain, skull and extremities of a mouse was a particularly sensitive phase. The threshold doses of radiation that induced a cleft palate and dilatation of the cerebral ventricle, and abnormal extremities were between 1.0 and 2.0 Gy, and between 0.5 and 1.0 Gy, respectively.
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111
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Oh H, Taffet GE, Youker KA, Entman ML, Overbeek PA, Michael LH, Schneider MD. Telomerase reverse transcriptase promotes cardiac muscle cell proliferation, hypertrophy, and survival. Proc Natl Acad Sci U S A 2001; 98:10308-13. [PMID: 11517337 PMCID: PMC56957 DOI: 10.1073/pnas.191169098] [Citation(s) in RCA: 222] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Cardiac muscle regeneration after injury is limited by "irreversible" cell cycle exit. Telomere shortening is one postulated basis for replicative senescence, via down-regulation of telomerase reverse transcriptase (TERT); telomere dysfunction also is associated with greater sensitivity to apoptosis. Forced expression of TERT in cardiac muscle in mice was sufficient to rescue telomerase activity and telomere length. Initially, the ventricle was hypercellular, with increased myocyte density and DNA synthesis. By 12 wk, cell cycling subsided; instead, cell enlargement (hypertrophy) was seen, without fibrosis or impaired function. Likewise, viral delivery of TERT was sufficient for hypertrophy in cultured cardiac myocytes. The TERT virus and transgene also conferred protection from apoptosis, in vitro and in vivo. Hyperplasia, hypertrophy, and survival all required active TERT and were not seen with a catalytically inactive mutation. Thus, TERT can delay cell cycle exit in cardiac muscle, induce hypertrophy in postmitotic cells, and promote cardiac myocyte survival.
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112
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Asou N, Adachi K, Tamura U, Kanamaru A, Kageyama S, Hiraoka A, Omoto E, Akiyama H, Tsubaki K, Saito K, Kuriyama K, Oh H, Kitano K, Miyawaki S, Takeyama U, Yamada O, Nishikawa K, Takahashi M, Matsuda S, Ohtake H, Ohno R. Analysis of prognostic factors in newly diagnosed patients with acute promyelocytic leukemia: the APL92 study of the Japan Adult Leukemia Study Group (JALSG). Cancer Chemother Pharmacol 2001; 48 Suppl 1:S65-71. [PMID: 11587370 DOI: 10.1007/s002800100308] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
All-trans-retinoic acid (ATRA) has been incorporated in front-line therapy for newly diagnosed acute promyelocytic leukemia (APL). We conducted a multicenter study of differentiation therapy with ATRA alone or in combination with chemotherapy followed by intensive postremission chemotherapy in patients with APL (the JALSG APL92 study), and analyzed prognostic factors to increase the cure rate in our subsequent trial. From 1992 to 1997, adult patients with newly diagnosed APL received oral ATRA 45 mg/m2 daily alone until complete remission (CR) if initial leukocyte counts were < 3.0x10(9)/l, and ATRA daily plus daunorubicin (DNR) 40 mg/m2x3 days plus enocitabine (BHAC) 200 mg/m2x5 days if leukocyte counts were > or =3.0 x 10(9)/l. If peripheral blasts exceeded 1.0x10(9)/l during therapy, DNRx3 days plus BHACx5 days was added. After CR was achieved, three courses of consolidation and six courses of maintenance/intensification chemotherapy were administered. Of 376 patients enrolled, 369 were evaluable (median age 46 years, range 15-86 years; median leukocyte counts 2.0x10(9)/l), and 333 (90%) achieved CR (94% of patients treated with ATRA alone, 88% with ATRA plus later chemotherapy, 89% with ATRA plus initial chemotherapy, and 86% with ATRA plus initial and later chemotherapy). At a median follow-up of 45 months, the predicted 6-year overall and event-free survival (EFS) rates for all patients were 65% and 52%, respectively. Favorable prognostic factors for CR were younger age, no or mild purpura, high serum total protein level, low lactate dehydrogenase level, and no or mild disseminated intravascular coagulation (DIC). Favorable prognostic factors for EFS were leukocyte counts < 10.0x10(9)/l, mild DIC, and no sepsis during induction therapy. In the JALSG APL97 study, we intensified chemotherapy for patients with leukocyte counts > or =3.0x10(9)/l, and are randomly testing whether further chemotherapy is required for APL patients with negative PCR for PML/retinoic acid receptor alpha in the maintenance phase.
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113
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Oh H, Oh GS, Seo WG, Pae HO, Chai KY, Kwon TO, Lee YH, Chung HT, Lee HS. Prunioside A: a new terpene glycoside from Spiraea prunifolia. JOURNAL OF NATURAL PRODUCTS 2001; 64:942-944. [PMID: 11473429 DOI: 10.1021/np0005513] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Prunioside A (1) has been isolated from an EtOAc-soluble extract of Spiraea prunifolia var. simpliciflora by a combination of chromatographic techniques. The structure was determined primarily by extensive NMR experiments. Compound 1 is a unique terpene glycoside. Its acetylated derivative (1a) inhibited nitric oxide production in murine macrophage-like RAW 264.7 cells in a dose-dependent manner.
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114
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Oh GS, Hong KH, Oh H, Pae HO, Kim IK, Kim NY, Kwon TO, Shin MK, Chung HT. 4-Acetyl-12,13-epoxyl-9-trichothecene-3,15-diol isolated from the fruiting bodies of Isariajaponica Yasuda induces apoptosis of human leukemia cells (HL-60). Biol Pharm Bull 2001; 24:785-9. [PMID: 11456118 DOI: 10.1248/bpb.24.785] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The fruiting bodies of Isaria fungi have been traditionally used in Korea to treat cancer. An apoptosis-inducing compound, 4-acetyl-12,13-epoxyl-9-trichothecene-3,15-diol, was isolated from the methanol extract of fruiting bodies of Isaria japonica Yasuda by bioassay-guided fractionation. The apoptosis of the human leukemia cells (HL-60) by the compound was accessed by propidium iodide-staining flow cytometric analysis, and apoptosis-inducing activity at IC50 concentration (10 nmol/l) was further confirmed by a nuclear morphological change, a ladder pattern of internucleosomal DNA fragmentation, and an activation of caspase-3.
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115
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Oh H, El Amin N, Davies T, Appelbaum PC, Edlund C. gyrA mutations associated with quinolone resistance in Bacteroides fragilis group strains. Antimicrob Agents Chemother 2001; 45:1977-81. [PMID: 11408211 PMCID: PMC90588 DOI: 10.1128/aac.45.7.1977-1981.2001] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mutations in the gyrA gene contribute considerably to quinolone resistance in Escherichia coli. Mechanisms for quinolone resistance in anaerobic bacteria are less well studied. The Bacteroides fragilis group are the anaerobic organisms most frequently isolated from patients with bacteremia and intraabdominal infections. Forty-four clinafloxacin-resistant and-susceptible fecal and clinical isolates of the B. fragilis group (eight Bacteroides fragilis, three Bacteroides ovatus, five Bacteroides thetaiotaomicron, six Bacteroides uniformis, and 22 Bacteroides vulgatus) and six ATCC strains of the B. fragilis group were analyzed as follows: (i) determination of susceptibility to ciprofloxacin, levofloxacin, moxifloxacin, and clinafloxacin by the agar dilution method and (ii) sequencing of the gyrA quinolone resistance-determining region (QRDR) located between amino acid residues equivalent to Ala-67 through Gln-106 in E. coli. Amino acid substitutions were found at hotspots at positions 82 (n = 15) and 86 (n = 8). Strains with Ser82Leu substitutions (n = 13) were highly resistant to all quinolones tested. Mutations in other positions of gyrA were also frequently found in quinolone-resistant and -susceptible isolates. Eight clinical strains that lacked mutations in their QRDR were susceptible to at least two of the quinolones tested. Although newer quinolones have good antimicrobial activity against the B. fragilis group, quinolone resistance in B. fragilis strains can be readily selected in vivo. Mutational events in the QRDR of gyrA seem to contribute to quinolone resistance in Bacteroides species.
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116
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Zentner GM, Rathi R, Shih C, McRea JC, Seo MH, Oh H, Rhee BG, Mestecky J, Moldoveanu Z, Morgan M, Weitman S. Biodegradable block copolymers for delivery of proteins and water-insoluble drugs. J Control Release 2001; 72:203-15. [PMID: 11389999 DOI: 10.1016/s0168-3659(01)00276-0] [Citation(s) in RCA: 387] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Release of several drugs from new ABA-type biodegradable thermal gels, ReGel, including proteins and conventional molecules, are presented. These are biodegradable, biocompatible polymers that demonstrate reverse thermal gelation properties. Organic solvents are not used in the synthesis, purification, or formulation of these polymers. The unique characteristics of ReGel hinge on the following two key properties: (1) ReGel is a water soluble, biodegradable polymer at temperatures below the gel transition temperature; (2) ReGel forms a water-insoluble gel once injected. This is consistent with a hydrophobically bonded gel state where all interactions are physical, with no covalent crosslinking. An increase in viscosity of approximately 4 orders of magnitude accompanies the sol--gel transition. The gel forms a controlled release drug depot with delivery times ranging from 1 to 6 weeks. ReGel's inherent ability to solubilize (400 to >2000-fold) and stabilize poorly soluble and sensitive drugs, including proteins is a substantial benefit. The gel provided excellent control of the release of paclitaxel for approximately 50 days. Direct intratumoral injection of ReGel/paclitaxel (OncoGel) results in a slow clearance of paclitaxel from the injection site with minimal distribution into any organ. Efficacies equivalent to maximum tolerated systemic dosing were observed at OncoGel doses that were 10-fold lower. Data on protein release (pGH, G-CSF, insulin, rHbsAg) and polymer biocompatibility are discussed.
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Kim MS, Oh H, Park C, Oh BH. Crystallization and preliminary X-ray crystallographic analysis of Escherichia coli RbsD, a component of the ribose-transport system with unknown biochemical function. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2001; 57:728-30. [PMID: 11320319 DOI: 10.1107/s0907444901003109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2000] [Accepted: 02/14/2001] [Indexed: 11/11/2022]
Abstract
The Escherichia coli high-affinity ribose-transport system consists of six proteins encoded by the rbs operon (rbsD, rbsA, rbsC, rbsB, rbsK and rbsR). Of the six components, RbsD is the only one whose function is unknown. In order to gain insights into the function of RbsD by structural analysis, we overexpressed and crystallized the protein as a first step toward this goal. RbsD was overexpressed in E. coli and crystallized using the hanging-drop vapour-diffusion method at 296 K. The crystals belong to the monoclinic space group C2, with unit-cell parameters a = 285.9, b = 92.3, c = 93.3 A, beta = 105.0 degrees. The unit cell is likely to contain 64 molecules of RbsD, with a crystal volume per protein mass (V(M)) of 2.43 A(3) Da(-1) and a solvent content of about 49.3% by volume. An equilibrium centrifugation analysis demonstrated that RbsD (MW = 15 292 Da) exists as an octamer in solution, suggesting that the asymmetric unit contains two octameric assemblies of RbsD. A native data set to 2.7 A resolution was obtained from a flash-cooled crystal.
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Otani A, Takagi H, Oh H, Koyama S, Honda Y. Angiotensin II induces expression of the Tie2 receptor ligand, angiopoietin-2, in bovine retinal endothelial cells. Diabetes 2001; 50:867-75. [PMID: 11289054 DOI: 10.2337/diabetes.50.4.867] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Recent studies have shown that angiopoietins (Angs) and their receptor, Tie2, play a role in vascular integrity and neovascularization. The renin-angiotensin system has been hypothesized to contribute to the development of diabetic retinopathy. In this study, we investigated the effect of angiotensin II (AII) on Ang1 and Ang2 expression in cultured bovine retinal endothelial cells (BRECs). AII stimulated Ang2 but not Ang1 mRNA expression in a dose- and time-dependent manner. This response was inhibited completely by angiotensin type 1 receptor (AT1) antagonist. AII increased the transcription of Ang2 mRNA, but did not change the half-life. Protein kinase C (PKC) inhibitor completely inhibited AII-induced Ang2 expression, and the mitogen-activated protein kinase (MAPK) inhibitor also inhibited it by 69.4+/-15.6%. In addition, we confirmed the upregulation of Ang2 in an AII-induced in vivo rat corneal neovascularization model. These data suggest that AII stimulates Ang2 expression through AT1 receptor-mediated PKC and MAPK pathways in BREC, and AII may play a novel role in retinal neovascularization.
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MESH Headings
- Angiopoietin-1
- Angiopoietin-2
- Angiopoietin-Like Protein 1
- Angiopoietin-like Proteins
- Angiopoietins
- Angiotensin II/pharmacology
- Animals
- Cattle
- Cells, Cultured
- Cornea/blood supply
- Endothelial Growth Factors/genetics
- Endothelium/cytology
- Endothelium/drug effects
- Endothelium/metabolism
- Intercellular Signaling Peptides and Proteins
- Lymphokines/genetics
- Membrane Glycoproteins/genetics
- Mitogen-Activated Protein Kinases/physiology
- Neoplasm Proteins/metabolism
- Neovascularization, Physiologic/drug effects
- Neovascularization, Physiologic/physiology
- Protein Kinase C/physiology
- Proteins/genetics
- Proteins/metabolism
- Proto-Oncogene Proteins
- RNA, Messenger/metabolism
- Rats
- Rats, Long-Evans
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptor, TIE-2
- Receptors, Angiotensin/physiology
- Retina/cytology
- Retina/drug effects
- Retina/metabolism
- Transcription, Genetic/drug effects
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
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Hawasli A, Boutt A, Cousins G, Schervish E, Oh H. Laparoscopic versus conventional live donor nephrectomy: experience in a community transplant program. Am Surg 2001; 67:342-5. [PMID: 11308000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Fifty-nine consecutive patients underwent live donor nephrectomy for transplantation. Twenty-nine patients (Group I) had open kidney procurement, and 30 patients (Group II) had laparoscopic procurement. The mean operative time in Group I was 2:30 hours (range 1:55-2:59), whereas in Group II it was 3:01 hours (1:54-5:21). All kidneys functioned immediately after transplantation. The average warm ischemia time was not calculated in Group I; it was 3.9 minutes (2-15) in Group II. Intraoperative complications occurred in two patients in Group II. One patient had bleeding from an accessory renal artery. The second patient had a tear in the splenic capsule. No ureteral complications occurred in either group. Postoperatively one patient in Group I developed incisional hernia, one developed pneumothorax, and two developed atelectasis. In Group II one patient developed pancreatitis, one developed flank ecchymosis, and two had suprapubic wound hematomas. Using the laparoscopic approach the hospital stay decreased from 4.1 to 1.27 days (69%) (P < 0.001) and return to work decreased from 28.4 to 14.8 days (49%) (P < 0.01). Live donation increased by 67 per cent. We conclude that the laparoscopic procurement of kidneys for transplantation compares well with the open method. It offers several advantages that may increase the living donor pool.
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Negoro S, Oh H, Tone E, Kunisada K, Fujio Y, Walsh K, Kishimoto T, Yamauchi-Takihara K. Glycoprotein 130 regulates cardiac myocyte survival in doxorubicin-induced apoptosis through phosphatidylinositol 3-kinase/Akt phosphorylation and Bcl-xL/caspase-3 interaction. Circulation 2001; 103:555-61. [PMID: 11157722 DOI: 10.1161/01.cir.103.4.555] [Citation(s) in RCA: 156] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND We recently reported that the activation of glycoprotein (gp) 130 by leukemia inhibitory factor (LIF) upregulates Bcl-xL and exerts antiapoptotic effects in cardiac myocytes. In addition, LIF induces activation of phosphatidylinositol (PI) 3-kinase and Akt, which are known to be required for cell survival. However, their regulatory roles in cell death remain unknown. METHODS AND RESULTS We investigated the fate of these proteins and the cytoprotective effects of LIF on doxorubicin (DOX)-induced apoptosis in cultured neonatal rat cardiac myocytes. Myocyte apoptosis increased significantly in DOX-treated cells but was significantly reduced by LIF pretreatment. The kinase activities of PI 3-kinase and Akt declined below basal levels but were partially recovered with LIF. Moreover, DOX-induced caspase-3 activation and decrease in Bcl-xL abundance are completely inhibited by LIF and caspase inhibitor. LIF phosphorylates Bad through PI 3-kinase and reduces the heterodimerization of Bad with Bcl-xL. Adenovirus transfer of the constitutively active form of Akt to cardiac myocytes restored cardiac myocyte survival after DOX treatment. Conversely, the dominant-negative form of Akt inhibited LIF-induced increase in cell viability and suppression of caspase-9 activation. CONCLUSIONS Activation of gp130 inhibits DOX-induced cell death in cardiac myocytes, resulting in the restoration of PI 3-kinase/Akt activities and in the inactivation of caspase-3, leading to facilitation of the protective function of Bcl-xL.
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Manabe S, Oh H, Amino K, Hata N, Yamakawa R. Ultrasound biomicroscopic analysis of posterior chamber intraocular lenses with transscleral sulcus suture. Ophthalmology 2000; 107:2172-8. [PMID: 11097591 DOI: 10.1016/s0161-6420(00)00412-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVE To investigate the postoperative problems of intraocular lenses (IOLs) with transscleral sulcus suture. DESIGN Retrospective observational case series. PARTICIPANTS Forty-one subjects (43 eyes) were included. INTERVENTION All eyes had undergone transscleral sulcus suture of IOLs. Surgeries were all performed by surgeons in our clinic using the same technique. MAIN OUTCOME MEASURES Ultrasound biomicroscopy of the suture sites, their surrounding structures, and central anterior chamber depth. Other parameters studied included visual acuity, aqueous flare, and routine ophthalmic examinations. RESULTS Thirty-two of 86 haptics were sutured at the ciliary sulcus (CS) region and 29 at the ciliary process region, which was the space between CS and pars plicata, and 25 posterior to pars plicata. We designated the cases with at least one haptic located in the CS region as the anterior group, and the other cases as the posterior group. In the anterior group, anterior chamber depth was significantly more shallow than in the fellow eye in which IOLs were fixed in the bag (P = 0.049). There was a statistically greater incidence of IOL iris contact in the anterior group than in the posterior group (P = 0.00057). Pigment dispersion was seen in seven cases, all of which were classified as anterior group. Eyes in the posterior group had more aqueous flare than their fellow eyes (P = 0.014). Two cases, in which more than two lines of postoperative best-corrected visual acuity was lost because of macular degeneration after cystoid macular edema, showed marked elevation of aqueous flare in the sutured eyes compared with their fellow eyes. Forty-one of 86 haptics had vitreous incarceration. CONCLUSIONS This technique has many limitations: the difficulty of suturing precisely at the ciliary sulcus, IOL iris contact, pigment dispersion, high aqueous flare, and vitreous incarceration. These induce two major postoperative complications: chronic inflammation and influence on the adjacent vitreous such as vitreous incarceration. The suturing technique and instruments need to be improved to diminish such complications.
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Negoro S, Kunisada K, Tone E, Funamoto M, Oh H, Kishimoto T, Yamauchi-Takihara K. Activation of JAK/STAT pathway transduces cytoprotective signal in rat acute myocardial infarction. Cardiovasc Res 2000; 47:797-805. [PMID: 10974228 DOI: 10.1016/s0008-6363(00)00138-3] [Citation(s) in RCA: 166] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVES We reported that the activation of gp130 transduced hypertrophic and cytoprotective signals via Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway in cardiac myocytes. Recent in vivo experiments have demonstrated that the JAK/STAT pathway is activated in acute pressure overload hearts. The present study was designed to examine whether the JAK/STAT pathway is also activated in acute myocardial infarction (AMI) and to determine its pathophysiological roles in ischemic heart disease. METHODS AND RESULTS AMI model was generated by the ligation of proximal left anterior descending coronary artery of male Wistar rat. They were sacrificed at various time points ranging from 1 to 24 h after coronary ligation and their hearts were examined. Tyrosine phosphorylation of STAT3 was observed in the myocardium obtained from both the ischemic area and the healthy border area adjacent to the infarcted area. The AMI rats were next randomly assigned to two groups, one with coronary ligation only (group M), and the other with coronary ligation with AG-490 treatment (1 mg/kg i.v., every 4 h), a specific JAK2 inhibitor (group A). In group A, phosphorylation of STAT3 was significantly suppressed and caspase-3 activity and Bax expression were significantly increased in the myocardium after AMI. In group M, few apoptotic myocytes were identified in the border area by means of TUNEL assay. However, a significant increase in apoptotic cells was observed in group A. CONCLUSIONS Administration of JAK2 inhibitor resulted in deterioration of myocardial viability in AMI hearts. The JAK/STAT pathway is activated in AMI myocardium and plays a pivotal role in cytoprotective signaling.
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Oh H, Nord CE, Barkholt L, Hedberg M, Edlund C. Ecological disturbances in intestinal microflora caused by clinafloxacin, an extended-spectrum quinolone. Infection 2000; 28:272-7. [PMID: 11073132 DOI: 10.1007/s150100070018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND The quinolones developed over the past few years have enhanced in vitro activity and a broader spectrum of antimicrobial activity compared to many other antimicrobial agents including the older quinolones. The present study focuses on the effect of clinafloxacin, a member of the new broad-spectrum quinolone class of antibiotics, on the normal intestinal microflora. SUBJECTS AND METHODS A total of 12 healthy volunteers received clinafloxacin orally, 200 mg twice daily for 7 days. Fecal specimens were collected at defined intervals before, during and after the administration in order to study the effect of clinafloxacin on the intestinal microflora and to correlate this effect with fecal clinafloxacin concentrations. Intestinal microorganisms isolated before, during and 2 weeks after clinafloxacin administration were tested for their suseptibility to clinafloxacin. RESULTS Oral administration of clinafloxacin resulted in high drug levels in feces (mean value 176.2 mg/kg on day 7) and pronounced ecological disturbances. The aerobic microflora was eradicated in 11 of the 12 subjects and the anaerobic microflora was strongly suppressed during administration. There was a significant emergence of clinafloxacin-resistant Bacteroides spp. strains (MIC > or = 4 mg/ml) during administration. The elevated MIC values still remained 2 weeks after discontinuation of the antibiotic (p < 0.001). CONCLUSION The emergence of clinafloxacin-resistant Bacteroides spp. demonstrates the necessity of restricting prescription for particular indications in order to preserve the efficacy of the highly active broad-spectrum quinolones.
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Funamoto M, Hishinuma S, Fujio Y, Matsuda Y, Kunisada K, Oh H, Negoro S, Tone E, Kishimoto T, Yamauchi-Takihara K. Isolation and characterization of the murine cardiotrophin-1 gene: expression and norepinephrine-induced transcriptional activation. J Mol Cell Cardiol 2000; 32:1275-84. [PMID: 10860769 DOI: 10.1006/jmcc.2000.1161] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cardiotrophin-1 (CT-1) is a novel cytokine capable of inducing hypertrophy in cardiac myocytes and belongs to the interleukin-6 family that exert their biological effects through gp130. To clarify the involvement and pathophysiological role of CT-1 in myocardial diseases, it is important to characterize the regulation of CT-1 gene expression. In this study, we isolated and characterized the mouse CT-1 gene and studied the expression of CT-1 mRNA under norepinephrine (NE) stimulation. The mouse CT-1 gene constitutes 5.4 kilobases (kb) in length and consists of three exons and two introns. When nucleotide sequences of the coding regions of exons were compared with those of human, exon 1, 2 and 3 share 96%, 84% and 81% homology, respectively. The 2.2 kb of 5; flanking lesion of the mouse CT-1 gene contains a variety of transcription factor binding motif (e.g. CREB, MyoD, NF-IL6, Nkx2.5, GATA). Fluorescent in situ hybridization (FISH) analysis demonstrated that the mouse CT-1 gene was located on chromosome 7F3. The expression of CT-1 mRNA in cardiac myocytes was markedly augmented by NE stimulation, both in vivo and in vitro. Promoter analysis using deletion constructs of the CT-1 gene indicated that the NE responsive element located between -2174/-1540 and this region contained the cAMP responsive element (CRE). Electrophoretic gel mobility shift assays showed enhanced binding activity to the CRE motif in the nuclear extracts from NE-stimulated cardiac myocytes. These studies indicate that CT-1 is abundantly expressed in the heart and that the CRE is a possible cis -acting element of the CT-1 gene under NE-stimulation. These data suggest that the CT-1 gene expression is regulated, at least partially, by transcriptional machinery.
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Ohashi K, Tanabe J, Watanabe R, Tanaka T, Sakamaki H, Maruta A, Okamoto S, Aotsuka N, Saito K, Nishimura M, Oh H, Matsuzaki M, Takahashi S, Yonekura S. The Japanese multicenter open randomized trial of ursodeoxycholic acid prophylaxis for hepatic veno-occlusive disease after stem cell transplantation. Am J Hematol 2000. [PMID: 10815785 DOI: 10.1002/(sici)1096-8652(200005)64: 1<32: : aid-ajh6>3.0.co; 2-n] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Hepatic veno-occlusive disease (VOD) is a common transplant-related complication of stem cell transplantation. There is no safe and proven therapy for established VOD, and attempts have focused on its prevention. Limited studies have suggested that prophylactic use of ursodeoxycholic acid (UDCA) reduced the incidence of VOD. To confirm the preventive effect of UDCA on VOD, we conducted a prospective, unblinded randomized, multicenter study of UDCA involving 132 patients who underwent stem cell transplantation for a variety of disorders. Sixty-seven patients were assigned to the UDCA-treated group, and 65 patients were assigned to the control group. The clinical characteristics of the two groups were similar with respect to primary diagnosis, age, sex, and baseline organ function. The preparative regimen and GVHD prophylaxis did not differ significantly between the two groups. UDCA was highly effective in preventing VOD, which occurred in only 3.0% in the UDCA-treated group, as opposed to 18.5% in the control group (P = 0.0043). There were no adverse effects attributable to UDCA. The initial promising report of a prophylactic effect of UDCA on VOD after stem cell transplantation was confirmed in this prospective study.
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