101
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Gaugler T, Kim D, Liao S. Comparing Two Survival Time Distributions: An Investigation of Several Weight Functions for the Weighted Logrank Statistic. COMMUN STAT-SIMUL C 2007. [DOI: 10.1080/03610910601161272] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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102
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Wang W, Yokoyama A, Omori M, Liao S, Zhu Y, Akasaka T, Uo M, Watari F. A novel sintered multi-walled carbon nanotubes bone material by spark plasma sintering method. Int J Oral Maxillofac Surg 2005. [DOI: 10.1016/s0901-5027(05)81203-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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103
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Amin A, Firooz N, Liao S. 201 CONFLICT OF INTEREST? A HOSPITALIST SERVING AS A HOSPICE MEDICAL DIRECTOR. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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104
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Kang L, Ma X, Cai L, Liao S, Sun L, Zhu H, Chen X, Shen D, Zhao S, Li C. Superinfection of Laodelphax striatellus with Wolbachia from Drosophila simulans. Heredity (Edinb) 2003; 90:71-6. [PMID: 12522428 DOI: 10.1038/sj.hdy.6800180] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Wolbachia are maternally inherited, intracellular alpha-proteobacteria that infect a wide range of arthropods. They manipulate the reproduction of hosts to facilitate their spread into host populations, through ways such as cytoplasmic incompatibility (CI), parthenogenesis, feminization and male killing. The influence of Wolbachia infection on host populations has attracted considerable interest in their possible role in speciation and as a potential agent of biological control. In this study, we used both microinjection and nested PCR to show that the Wolbachia naturally infecting Drosophila simulans can be transferred into a naturally Wolbachia-infected strain of the small brown planthopper Laodelphax striatellus, with up to 30% superinfection frequency in the F(12) generation. The superinfected males of L. striatellus showed unidirectional CI when mated with the original single-infected females, while superinfected females of L. striatellus were compatible with superinfected or single-infected males. These results are, to our knowledge, the first to establish a superinfected horizontal transfer route for Wolbachia between phylogenetically distant insects. The segregation of Wolbachia from superinfected L. striatellus was observed during the spreading process, which suggests that Wolbachia could adapt to a phylogenetically distant host with increased infection frequency in the new host population; however, it would take a long time to establish a high-frequency superinfection line. This study implies a novel way to generate insect lines capable of driving desired genes into Wolbachia-infected populations to start population replacement.
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Wu WN, McKown LA, Liao S. Metabolism of the analgesic drug ULTRAM (tramadol hydrochloride) in humans: API-MS and MS/MS characterization of metabolites. Xenobiotica 2002; 32:411-25. [PMID: 12065063 DOI: 10.1080/00498250110113230] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
1. Metabolism of the analgesic agent tramadol hydrochloride has been investigated after a single oral administration of tramadol to three male volunteers (100 mg/subject), and a urine pool (4-12h) was obtained. 2. Unchanged tramadol and a total of 23 metabolites, consisting of 11 Phase I metabolites (M1-11) and 12 conjugates (seven glucuronides, five sulphates), were profiled, characterized and tentatively identified in urine on the basis of API ionspray-MS and MS/MS data. 3. Of the metabolites, five (M1-5) had been previously identified. 4. The metabolites were formed via the following six metabolic pathways: (1) O-demethylation, (2) N-demethylation, (3) cyclohexyl oxidation, (4) oxidative N-dealkylation, (5) dehydration and (6) conjugation. 5. Pathways 1-3 appear to be major routes, forming seven O-desmethyl/N-desmethyl and hydroxycyclohexyl metabolites. 6. Pathways 1-3 in conjunction with pathway 6 produced seven glucuronides along with five sulphates. 7. In addition, the in vitro metabolism of tramadol was conducted using a human liver microsomal fraction in the presence of an NADPH-generating system. Unchanged tramadol (82% of the sample) plus eight metabolites (M1, M2, M4-6, tramadol-N-oxide (M31), OH-cyclohexyl-M1 (M32) and dehydrated tramadol-N-oxide), were profiled and tentatively identified on the basis of MS and MS/MS data.
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106
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Tao Q, Stone DJ, Borenstein MR, Codd EE, Coogan TP, Desai-Krieger D, Liao S, Raffa RB. Differential tramadol and O-desmethyl metabolite levels in brain vs. plasma of mice and rats administered tramadol hydrochloride orally. J Clin Pharm Ther 2002; 27:99-106. [PMID: 11975693 DOI: 10.1046/j.1365-2710.2002.00384.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To investigate a possible differential brain uptake of tramadol vs. its major metabolite (O-desmethyl tramadol; M1) in mice and rats. METHODS An extraction and measurement technique (gas chromatograph equipped with a nitrogen phosphorus detector) was used to measure plasma and brain levels of tramadol and M1 at intervals 10-300 min after oral dosing of tramadol hydrochloride to mice and rats. RESULTS For all doses of tramadol administered (5, 10, 20, or 40 mg/kg), tramadol and M1 plasma levels were greatest 10 min after dosing: in mice, peak tramadol plasma levels were 47.75-736.72 ng/mL and peak M1 levels were 75.30-1084.92 ng/mL; in rats, peak tramadol plasma levels were 185.03-455.81 ng/mL and peak M1 levels were 106.74-455.70 ng/mL. Tramadol brain levels were also greatest 10 min after dosing. In mice, peak tramadol brain levels were 226.42-1847.46 ng/g. Peak M1 levels (72.17-572.97 ng/g) occurred 20-60 min after dosing. In rats, peak tramadol brain levels were 258.50-1777.37 ng/g and peak M1 levels were 80.35-289.60 ng/g. In mice, the ratio of tramadol/M1 in plasma was 0.5-1.0 throughout the measurements, whereas the ratio in brain was about 10 at 10 min and about 2 from 20 to 50 min. In rats, the ratio of tramadol/M1 in plasma was 0.5-1.5, whereas the ratio in brain was about 15 at 10 min and about 4-7 thereafter. CONCLUSION In mice and rats, there appears to be preferential brain vs. plasma distribution of tramadol over M1.
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107
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Abdel-Rahman SM, Leeder JS, Wilson JT, Gaedigk A, Gotschall RR, Medve R, Liao S, Spielberg SP, Kearns GL. Concordance between tramadol and dextromethorphan parent/metabolite ratios: the influence of CYP2D6 and non-CYP2D6 pathways on biotransformation. J Clin Pharmacol 2002; 42:24-9. [PMID: 11808821 DOI: 10.1177/0091270002042001002] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cytochrome P4502D6 (CYP2D6) activity has been shown to be a determinant of both the pharmacokinetics and pharmacodynamics of tramadol in adults. This study evaluated the association between CYP2D6 activity, as determined by dextromethorphan (DM) urinary metabolite ratio, and tramadol biotransformation in 13 children (7-16 years). CYP2D6 genotype was determined by XL-PCR and PCR/RFLP. Phenotype was assessed by HPLC quantitation of DM and its metabolites from a 12- to 24-hour urine collection following a single oral dose of DM. There was only a modest correlation between tramadol/M1 (metabolite 1) plasma concentration or AUC and the DM/dextrorphan (DX) urinary molar ratio in the study cohort; however, when subjects were segregated based on the number of functional CYP2D6 alleles, a much stronger relationship was observed for subjects with two functional alleles, with essentially no relationship evident in those individuals with one functional allele. Further evaluation of these data suggested that the CYP2D6-mediated metabolite (M1) is formed to a lesser extent, and the formation of the non-CYP2D6 product (M2) is more pronounced in subjects with one versus two functional alleles. Thus, the number of functional CYP2D6 alleles and the availability of alternative cytochromes P450 capable of metabolizing tramadol may explain the poor association between DM, a well-characterized CYP2D6 probe, and tramadol in a population of CYP2D6 extensive metabolizers.
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108
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Liao S. The medicinal action of androgens and green tea epigallocatechin gallate. Hong Kong Med J 2001; 7:369-74. [PMID: 11773671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Unorthodox (non-traditional or alternative) medicinal practices have been expanding very rapidly in western countries. Modern physicians, scientists, and non-traditional medicine practitioners now must join forces to promote evidence-based medicine to benefit patients. Green tea extracts are among the most widely used ancient medicinal agents, while androgens are probably the oldest drugs used in a purified form in traditional Chinese medicine. It is now clear that a specific green tea catechin, (-)epigallocatechin-3-gallate, can modulate the production and biological actions of androgens and other hormones. Modulation of androgenic activity and administration of (-)epigallocatechin-3-gallate may be useful for the treatment of various hormone-related abnormalities, such as benign prostatic hyperplasia, baldness, and acne, as well as androgen-dependent and -independent prostate cancers. (-)Epigallocatechin-3-gallate has also been shown to modulate appetite and control obesity in animals.
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109
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Tao Q, Stone DJ, Borenstein MR, Jean-Bart V, Codd EE, Coogan TP, Desai-Krieger D, Liao S, Raffa RB. Gas chromatographic method using nitrogen-phosphorus detection for the measurement of tramadol and its O-desmethyl metabolite in plasma and brain tissue of mice and rats. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 763:165-71. [PMID: 11710575 DOI: 10.1016/s0378-4347(01)00388-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A method that allows the measurement of plasma and brain levels of the centrally-acting analgesic tramadol and its major metabolite (O-desmethyl tramadol) in mice and rats was developed using gas chromatography equipped with nitrogen-phosphorus detection (GC-NPD). Plasma samples were extracted with methyl tert.-butyl ether (MTBE) and were injected directly into the GC system. Brain tissue homogenates were precipitated with methanol, the resulting supernatant was dried then acidified with hydrochloric acid. The aqueous solution was washed with MTBE twice, alkalinized, and extracted with MTBE. The MTBE layer was dried, reconstituted and injected into the GC system. The GC assay used a DB-1 capillary column with an oven temperature ramp (135 to 179 degrees C at 4 degrees C/min). Dextromethorphan was used as the internal standard. The calibration curves for tramadol and O-desmethyl tramadol in plasma and brain tissue were linear in the range of 10 to 10000 ng/ml (plasma) and ng/g (brain). Assay accuracy and precision of back calculated standards were within +/- 15%.
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110
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Lin H, He W, Liu T, Qin J, Luo Y, Liao S, Zheng B. Aortic and mitral valve replacement with retrograde perfusion in the beating heart. Chin Med J (Engl) 2001; 114:1180-3. [PMID: 11729515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
OBJECTIVE To estimate the value of aortic valves and combined mitral valve replacement with retrograde perfusion in beating hearts. METHODS Continuous retrograde coronary sinus perfusion with beating hearts was used in 83 patients undergoing aortic valve or aortic valve combined with mitral valve replacement, without application of cardioplegia. After aortic valve replacement, the retrograde perfusion was changed to antegrade perfusion for mitral valve replacement or correction of the other deformities (group A). Cold blood cardioplegia solution (15 degrees C) was infused at intervals in 20 cases (group B). The following parameters were tested: lactate, ET, CTn-T and MDA in blood; myocardial ultra-structure; and cardiac rhythm and cardiac output (CO). RESULTS All biochemical values increased after cardiopulmonary bypass (P < 0.05-0.01). Empty and beating heart sinus rhythm was maintained in group A. Myocardial ultrastructure did not change significantly. The pump was stopped smoothly as the surgical procedure finished. No postoperative low cardiac output syndrome or arrhythmia was observed. Eight-one patients recovered smoothly, two died from renal failure or infective shock. When the pump stopped, all patients in group B were supported by 5-10 micrograms.kg-1.min-1 dopamine. Transient pacing was used in 9 patients. One patient died from low cardiac output syndrome. CONCLUSION This method is a good myocardial protection which simulates physiologic status. It is applicable to aortic valve and combined mitral valve replacement of patients with large heart or heart failure and long time aortic cross-clamping. Ideal clinical effect can be achieved.
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111
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Kuroki M, Abe H, Imakiirei T, Liao S, Uchida H, Yamauchi Y, Oikawa S, Kuroki M. Identification and comparison of residues critical for cell-adhesion activities of two neutrophil CD66 antigens, CEACAM6 and CEACAM8. J Leukoc Biol 2001; 70:543-50. [PMID: 11590190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
CEACAM6 (CD66c) and CEACAM8 (CD66b) are cell-adhesion proteins on neutrophils that belong to the human carcinoembryonic antigen (CEA) family. CEACAM6 reveals homophilic adhesion and heterophilic adhesion to other CEACAM family antigens including CEACAM8, CEACAM1, and CEA, whereas CEACAM8 exhibits only heterophilic adhesion to CEACAM6. Here, we investigated and compared structural requirements for the homophilic adhesion of CEACAM6 and heterophilic adhesion between CEACAM6 and CEACAM8 at the amino acid level by using CHO transfectants expressing their mutant and chimeric proteins. The NH(2)-terminal domain (N-domain) of CEACAM6 expressed on a CHO cell was suggested to bind the N-domain of CEACAM6 or CEACAM8 on the opposing cell. By homologue-scanning mutagenesis, we found that the locations of the sequences critical for the adhesion of CEACAM6 to itself and to CEACAM8 are overlapped and that they are highly similar but not identical to the locations of the residues previously shown to be essential for the binding of CEACAM antigens to Opa proteins of pathogenic NEISSERIAE: Our findings imply that subtle differences in the N-domain sequences determine the specificity of the CEACAM antigens on neutrophils for interaction with the same or different CEACAM antigens and the bacterial proteins.
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Abstract
Recently, a number of nuclear receptors have been identified as key regulators of cholesterol homeostasis. Two of these, liver X receptor alpha (LXRalpha) (NR1H3) [1] and ubiquitous receptor (UR) (NR1H2) [1], appear to be involved in cholesterol reverse transport and disposal. LXRalpha null gene mice fail to adapt metabolically to high-cholesterol diets. We have recently shown that some 6alpha-hydroxylated bile acid analogs are selective activators of LXRalpha. In this report, we show that these orally administered LXRalpha agonists have an overall hypolipidemic effect in hypercholesterolemic rats, mice and hamsters, which indicates that in these animal models, endogenous LXRalpha agonist is a limiting factor for induction of cholesterol disposal. Furthermore, in animals, these 6alpha-hydroxylated bile acid analogs exhibit a unique pharmacokinetic profile and do not increase the serum triglyceride level; therefore, they may represent a novel class of therapeutic agents for cholesterol management.
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113
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Yang S, Zhang B, Wang J, Liao S, Han J, Wei J, Hou L. Monoclonal antibodies against human telomerase reverse transcriptase (hTERT): preparation, characterization, and application. Hybridoma (Larchmt) 2001; 20:249-55. [PMID: 11604111 DOI: 10.1089/027245701753179839] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The catalytic subunit of human telomerase reverse transcriptase (hTERT), is the necessary and rate-limiting component to telomerase activation in cancer cells. To develop monoclonal antibodies (MAbs) against hTERT, a peptide-hTERT(9)-derived from specific motif T of hTERT was synthesized. Through fusion of splenocytes of BALB/c mice immunized with hTERT(9) with mouse myeloma cells, hybridomas were generated and clones secreting anti-hTERT(9) antibody were screened. After three rounds of limited dilution of candidate clones, three of which present stable and constant antibody production. The MAbs were hTERT(9)-specific and reactive with native hTERT of human cancer cells or tissues in Western blot and immunohistochemistry. The heavy chain variable regions from three hybridomas were cloned and sequenced confirming their mouse Ig derivation. The described investigation suggested that the generated MAbs to hTERT(9) could recognize native hTERT and be useful to cancer research.
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Xie Z, Pan D, Liao S. [Combination chemotherapy with paclitaxel and carboplatin in the treatment of advanced non-small cell lung cancer]. ZHONGGUO FEI AI ZA ZHI = CHINESE JOURNAL OF LUNG CANCER 2001; 4:194-6. [PMID: 21047476 DOI: 10.3779/j.issn.1009-3419.2001.03.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND To study the efficacy and toxicity of combined chemotherapy of paclitaxel and carboplatin in patients with advanced non-small cell lung cancer (NSCLC). METHODS Seventy-eight patients with advanced NSCLC received combined chemotherapy of paclitaxel 150 mg/m² and carboplatin 300 mg/m². RESULTS The response rate of native patients was 56.9% (33/58) and that of the repeated treatment group was 35% (7/20). The overall response rate was 51.3%(40/78). Four patients (5.1%) had complete response. The median duration of survival was 9 months, and 1-year survival rate was 33.3% (26/78). Toxicity was chiefly hematologic in the form of neutropenia. The major nonhematologic toxicity was arthromyalgia. CONCLUSIONS Combination chemotherapy of paclitaxel and carboplatin is well tolerated and effective in the treatment of advanced NSCLC.
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Liao S, Kao YH, Hiipakka RA. Green tea: biochemical and biological basis for health benefits. VITAMINS AND HORMONES 2001; 62:1-94. [PMID: 11345896 DOI: 10.1016/s0083-6729(01)62001-6] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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116
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Yang J, Liang Y, Liao S. [Pulmonary hyalinizing granuloma: a case report and a review of the literature]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 2001; 24:369-70. [PMID: 11802992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To highlight the characteristics of pulmonary hyalinizing granuloma (PHG). METHOD One patient with PHG confirmed by pathological assessment was presented and relevant literatures were reviewed. RESULTS PHG is a rare disease characterized by multiple bilateral pulmonary nodules. Symptoms include cough, dyspnea, chest pain, hemoptysis, fever and fatigue. Histologically, the nodules consist of haphazard or whorled arrays of lamellar, keloid - like collagen. Evidence suggests that the nodules are the result of a chronic exaggerated immune response. CONCLUSIONS PHG should be considered in patients showing multiple bilateral pulmonary nodules. The clinical course of PHG in most patients is benign. At present, there is no effective therapy.
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Song C, Hiipakka RA, Liao S. Auto-oxidized cholesterol sulfates are antagonistic ligands of liver X receptors: implications for the development and treatment of atherosclerosis. Steroids 2001; 66:473-9. [PMID: 11182136 DOI: 10.1016/s0039-128x(00)00239-7] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Liver X receptors (LXRs) are members of the nuclear receptor superfamily that are involved in regulation of cholesterol transport and metabolism. Expression of cholesterol 7alpha-hydroxylase, cholesteryl ester transfer protein and certain ATP-binding cassette transporters that are responsible for cholesterol efflux from cells is regulated by LXR and its ligands. In this report we show that 5alpha, 6alpha-epoxycholesterol-3-sulfate (ECHS) and 7-ketocholesterol-3-sulfate inhibit transactivation of a reporter gene by LXR. Non-sulfated forms of these compounds, as well as many other steroid sulfates, had no antagonistic activity. Using chimeric receptors, the antagonistic activity of ECHS was dependent on its interaction with the ligand-binding domain of LXR. ECHS disrupts recruitment of the co-activator Grip 1 into a complex with agonist-bound LXR and this may be responsible for the observed antagonistic properties of these compounds. In various cultured cells, these LXR antagonists also promote de novo cholesterol synthesis and apoptosis. 7-Ketocholesterol and 5alpha, 6alpha-epoxycholesterol are present in blood and have been found in atherosclerotic plaques. If sulfated forms of these oxidized sterols are also present, they may have an important role in foam cell formation by inhibiting LXR function. Since LXR agonists can counteract the activity of these antagonists, they may have therapeutic potential against atherosclerosis.
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Liao S, Amin A, Rucker L. A longitudinal home hospice rotation for internal medicine residents. ACADEMIC MEDICINE : JOURNAL OF THE ASSOCIATION OF AMERICAN MEDICAL COLLEGES 2001; 76:518-519. [PMID: 11346557 DOI: 10.1097/00001888-200105000-00051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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119
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Liao S, Khare PD, Arakawa F, Kuroki M, Hirose Y, Fujimura S, Tomita Y, Kuroki M. Targeting of LAK activity to CEA-expressing tumor cells with an anti-CEA scFv/IL-2 fusion protein. Anticancer Res 2001; 21:1673-80. [PMID: 11497246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
BACKGROUND Fusion of tumor-specific monoclonal antibody (MAb) and cytokines has proved to be an efficient way to target cytokines to tumor cells and hence focuses the killing activity of effector cells to the target cells. We previously produced a high affinity MAb, F11-39, against carcinoembryonic antigen (CEA), which is often overexpressed on the surface of various tumor cells. MATERIALS AND METHODS To target the cytotoxicity of effector cells to CEA-expressing tumor cells, we employed recombinant DNA techniques to fuse recombinant human interleukin-2 (rhIL-2) to a single chain variable fragment (scFv) antibody derived from F11-39. The resulting fusion protein, designated F39scFv/IL-2, was expressed in the Sp2/0-Ag14 mouse hybridoma cells, purified by CEA-affinity chromatography and characterized for the CEA-binding specificity and the IL-2 biological activity. RESULTS F39scFv/IL-2 protein effectively targeted rhIL-2 onto the surface of CEA-expressing tumor cells and consequently introduced a specific cytotoxicity of lymphokine-activated killer cells to the tumor cells. CONCLUSIONS This approach may be used for in vivo administration to localize IL-2 to tumor tissues, maximizing the immune response to CEA-expressing tumors while keeping systemic side effects to a minimum.
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Liao S, Miralles M, Kelley BJ, Curci JA, Borhani M, Thompson RW. Suppression of experimental abdominal aortic aneurysms in the rat by treatment with angiotensin-converting enzyme inhibitors. J Vasc Surg 2001; 33:1057-64. [PMID: 11331849 DOI: 10.1067/mva.2001.112810] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE Pathologic remodeling of the extracellular matrix is a critical mechanism in the development and progression of abdominal aortic aneurysms (AAAs). Although angiotensin-converting enzyme (ACE) inhibitors are known to alter vascular wall remodeling in other conditions, their effects on AAAs are unknown. In this study we assessed the effect of ACE inhibitors in a rodent model of aneurysm development. METHODS Male Wistar rats underwent transient aortic perfusion with porcine pancreatic elastase, followed by treatment with one of three ACE inhibitors (captopril [CP], lisinopril [LP], or enalapril [EP]), an angiotensin (AT)1 receptor antagonist (losartan [LOS]), or water alone (9 rats in each group). Blood pressure and aortic diameter (AD) were measured before elastase perfusion and on day 14, with an AAA defined as an increase in AD (DeltaAD) of more than 100%. The structural features of the aortic wall were examined by means of light microscopy. RESULTS Aneurysmal dilatation consistently developed within 14 days of elastase perfusion in untreated rats, coinciding with the development of a transmural inflammatory response and destruction of the elastic media (mean DeltaAD, 223% +/- 28%). All three ACE inhibitors prevented AAA development (mean DeltaAD: CP, 67% +/- 4%; LP, 18% +/- 12%; and EP, 14% +/- 3%; each P <.05 vs controls). ACE inhibitors also attenuated the degradation of medial elastin without diminishing the inflammatory response. Surprisingly, the aneurysm-suppressing effects of ACE inhibitors were dissociated from their effects on systemic hemodynamics, and LOS had no significant effect on aneurysm development compared with untreated controls (mean DeltaAD, 186% +/- 19%). CONCLUSION Treatment with ACE inhibitors suppresses the development of elastase-induced AAAs in the rat. Although this is associated with the preservation of medial elastin, the mechanisms underlying these effects appear to be distinct from hemodynamic alterations alone or events mediated solely by AT1 receptors. Further studies are needed to elucidate how ACE inhibitors influence aortic wall matrix remodeling during aneurysmal degeneration.
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121
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Liao S, Shenderovich M, Kövér KE, Zhang Z, Hosohata K, Davis P, Porreca F, Yamamura HI, Hurby VJ. Synthesis, biology, NMR and conformation studies of the topographically constrained delta-opioid selective peptide analogs of [beta-iPrPhe(3)]deltorphin I. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 2001; 57:257-76. [PMID: 11328484 DOI: 10.1046/j.1397-002x.2000.00000.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Replacement of Phe3 in the endogenous delta-opioid selective peptide deltorphin I with four optically pure stereoisomers of the topographically constrained, highly hydrophobic novel amino acid beta-isopropylphenylalanine (beta-iPrPhe) produced four pharmacologically different deltorphin I peptidomimetics. Radiolabeled ligand-binding assays and in vitro biological evaluation indicate that the stereoconfiguration of the iPrPhe residue plays a crucial role in determining the binding affinity, bioactivity and selectivity of [beta-iPrPhe3]deltorphin I analogs: a (2S,3R) configuration of the iPrPhe3 residue in [beta-iPrPhe3]deltorphin I provided the most desirable biological properties with binding affinity (IC50 = 2 nM), bioassay potency (IC50 = 1.23 nM in MVD assay) and exceptional selectivity for the delta-opioid receptor over the mu-opioid receptor (30 000). Further conformational studies based on two-dimensional NMR and computer-assisted molecular modeling suggested a model for the possible bioactive conformation in which the Tyr1 and (2S,3R)-beta-iPrPhe3 residues adopt trans side-chain conformations, and the linear peptide backbone favors a distorted beta-turn conformation.
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MESH Headings
- Analgesics, Opioid/chemical synthesis
- Analgesics, Opioid/chemistry
- Analgesics, Opioid/metabolism
- Analgesics, Opioid/pharmacology
- Animals
- Computer Simulation
- Guinea Pigs
- In Vitro Techniques
- Male
- Mice
- Models, Molecular
- Molecular Structure
- Muscle Contraction/drug effects
- Muscle, Smooth/drug effects
- Muscle, Smooth/physiology
- Nuclear Magnetic Resonance, Biomolecular
- Oligopeptides/chemical synthesis
- Oligopeptides/chemistry
- Oligopeptides/metabolism
- Oligopeptides/pharmacology
- Protein Conformation
- Radioligand Assay
- Rats
- Rats, Sprague-Dawley
- Receptors, Opioid, delta/chemistry
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Liao S, Lin J, Dang MT, Zhang H, Kao YH, Fukuchi J, Hiipakka RA. Growth suppression of hamster flank organs by topical application of catechins, alizarin, curcumin, and myristoleic acid. Arch Dermatol Res 2001; 293:200-5. [PMID: 11380153 DOI: 10.1007/s004030000203] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hamster flank organ growth, as measured by an increase in the area of the pigmented macule, is androgen-dependent. When flank organs of a castrated hamster are treated topically with testosterone, the flank organ becomes larger and darker. Since this growth is known to be dependent on the intracellular active androgen, 5alpha-dihydrotestosterone (DHT), inhibitors of 5alpha-reductase which converts testosterone to DHT can inhibit the growth of the flank organ. Certain unsaturated aliphatic fatty acids, such as gamma-linolenic acid and myristoleic acid, as well as other natural compounds, including alizarin and curcumin, are 5alpha-reductase inhibitors and inhibited flank organ growth. Green tea catechins, including (-)-epicatechin-3-gallate, and (-)-epigallo-catechin-3-gallate (EGCG) are also 5alpha-reductase inhibitors and inhibited flank organ growth. However, (-)-epicatechin and (-)-epigallocatechin, which are not 5alpha-reductase inhibitors, also inhibited flank organ growth. EGCG also inhibited DHT-dependent growth of flank organs. These catechins, therefore, may act by a mechanism other than inhibition of 5alpha-reductase. The effect of EGCG and other compounds was localized at the site of application; they did not affect the growth of the contralateral flank organ in the same animal. Since these compounds do not appear to exhibit systemic effects, they may be potentially useful for treatment of androgen-dependent skin disorders.
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Kokontis JM, Wagner AJ, O'Leary M, Liao S, Hay N. A transcriptional activation function of p53 is dispensable for and inhibitory of its apoptotic function. Oncogene 2001; 20:659-68. [PMID: 11313999 DOI: 10.1038/sj.onc.1204139] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2000] [Revised: 11/22/2000] [Accepted: 11/29/2000] [Indexed: 11/09/2022]
Abstract
The tumor suppressor p53 is an inducer of cell cycle arrest and programmed cell death (apoptosis). The ability of p53 to induce cell cycle arrest is linked to its ability to induce transcription of genes such as the cyclin-dependent kinase inhibitor p21. However, the dependence of p53-mediated apoptosis on transcriptional activation remains controversial. Ectopic expression of a temperature-sensitive (ts) p53 allele induced expression of p53 target genes and elicited both G1 and G2/M cell cycle arrest upon shift to the permissive temperature. Ectopic expression of the same ts p53 allele with two additional point mutations (Gln22, Ser23) that abolish p53-transcriptional activation did not induce p53 target genes and G1 nor G2/M cell cycle arrest. In HCT116 colon carcinoma cells ectopic expression of wild type p53 does not elicit apoptosis whereas p53 mutant deficient in trans-activation induces apoptosis. The ability of wild type p53 to induce apoptosis is restored in HCT116 cells that are null for p21. However, the trans-activation deficient mutant of p53 is still more potent mediator of apoptosis than wild type p53 in the p21 null cells. Although the ability of Gln22,Ser23 to trans-activate p53 target genes is diminished, it retains the ability to repress Bcl-2 expression. Thus, we conclude that while ectopic expression of wild type p53 can induce both G1 and G2/M arrest, in a p21 dependent manner, without apoptosis, a p53 mutant defective in trans-activation elicits apoptosis without inducing cell cycle arrest. Further, the anti-apoptotic function of p53 is dependent on trans-activation and is linked to cell cycle arrest. The results strongly suggest that the trans-activation deficient mutant is a more potent inducer of apoptosis because it lost its anti-apoptotic function and retains its ability to repress pro-apoptotic genes such as Bcl-2. Taken together, the results imply that employing a trans-activation deficient p53 in gene therapy approaches or the use of drugs that convert mutant p53 to a trans-activation-independent mediator of apoptosis may be much more efficient therapeutic approaches than current approaches that employ wild type p53.
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Hao B, Li Y, Yang Y, Wang Y, Huang F, Liao S, Wang Z, Si Y, Zhu W. [Genetic polymorphism of eight STR loci in the Han population in Henan province]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 2001; 18:35-8. [PMID: 11172640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
OBJECTIVE To investigate the allele frequencies of eight short tandem repeats(STR) loci: TH01, FES, D19S400, D7S820, D16S539, D20S161, D3S1545 and D5S818 in Han population in Henan province. METHODS DNA was extracted with phenol-chloroform from EDTA-blood samples of the unrelated individuals in Henan province and amplified with PCR technique. The PCR product was analyzed with the undenatured PAGE vertical electrophoresis and silver-stain. RESULTS The authors got the frequencies of the eight loci. The heterozygosities of the eight loci are 0.66, 0.67, 0.80, 0.76, 0.79, 0.79, 0.78 and 0.78; the discrimination powers are 0.83, 0.83, 0.94, 0.91, 0.93, 0.93, 0.92 and 0.92. CONCLUSION The heterozygosities of the eight loci are high and the frequencies are in good agreement with Hardy-Weinberg equilibrium, so the eight loci can be used in individual identification testing.
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Liao S, Chen W, Kuo J, Chen C. Association of serum estrogen level and ischemic neuroprotection in female rats. Neurosci Lett 2001; 297:159-62. [PMID: 11137752 DOI: 10.1016/s0304-3940(00)01704-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Estrogen-related ischemic neuroprotection has been documented in male and ovariectomized female rats. The precise molecular mechanism underlying estrogen's neuroprotective effect remains obscure. In the present study, we examined whether endogenous estrogen levels affect post-ischemic outcomes in normal cycling female rats. Occlusion of both the common carotid arteries and the right middle cerebral artery (1.5 h) followed by reperfusion (24 h) caused cortical infarction, increased neutrophil accumulation, and elevated antioxidant enzyme and lactate dehydrogenase activities. These post-ischemic changes varied in the female rats and were inversely correlated with circulating estrogen levels. More severe post-ischemic changes and injury accompanied the decline in circulating estrogen levels in normal cycling female rats, indicating that estrogen is probably the major hormonal player in female resistance to ischemia.
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