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Liu AC, Gong XL. [Correlation on HER2 gene amplification by fluorescence in situ hybridization and membrane integrity expression pattern by immunohistochemistry in breast cancer]. Zhonghua Bing Li Xue Za Zhi 2023; 52:1160-1162. [PMID: 37899325 DOI: 10.3760/cma.j.cn112151-20230626-00424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Affiliation(s)
- A C Liu
- Department of Pathology, Yueyang Central Hospital of Hunan Province, Yueyang 414000, China
| | - X L Gong
- Department of Pathology, Yueyang Central Hospital of Hunan Province, Yueyang 414000, China
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2
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Quan LN, Song HT, Chen X, Jiang L, Liu AC. [Pathological transformation of angioimmunoblastic T-cell lymphoma into diffuse large B-cell lymphoma: a case report]. Zhonghua Xue Ye Xue Za Zhi 2021; 41:957. [PMID: 33333705 PMCID: PMC7767804 DOI: 10.3760/cma.j.issn.0253-2727.2020.11.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- L N Quan
- Department of Hematology, Harbin Medical University Cancer Hospital, Harbin 150081, China
| | - H T Song
- Department of Pathology, Harbin Medical University Cancer Hospital, Harbin 150081, China
| | - X Chen
- Department of Hematology, Harbin Medical University Cancer Hospital, Harbin 150081, China
| | - L Jiang
- Department of Hematology, Harbin Medical University Cancer Hospital, Harbin 150081, China
| | - A C Liu
- Department of Hematology, Harbin Medical University Cancer Hospital, Harbin 150081, China
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Liu AC, Chen Y, Jia JS, Gao SY, Liu YY. [Non-Hodgkin's lymphoma mimicking Mikulicz disease: a case report]. Beijing Da Xue Xue Bao Yi Xue Ban 2016; 48:1074-1076. [PMID: 27987516] [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: 06/06/2023]
Abstract
IgG4-related disease is a systemic disorder involving a spectrum of multiple indications, and various histopathological features are shared among different IgG4-related disease subtypes, which challenge diagnosis, although certain syndromes have organ-specific involvement. Among them, Mikulicz's disease affecting the salivary and lacrimal glands, distinguished by often elevated levels of serum IgG4, infiltration of IgG4+ plasma cells into target tissues, and diffuse swelling, mass formation, or fibrosis of affected organs. However, there are several diseases, which could manifest as salivary gland swelling, mimicking Mikulicz's disease, such as Sjogren's syndrome, mumps virus infection, obstruction of parotid duct, non-Hodgkin's lymphoma (NHL), and so on. So differential diagnosis is important and essential as to the salivary gland swelling. In this paper, we analyzed a case of a 59-year-old male with symmetric salivary gland swelling. Mikulicz's disease was misdiagnosed at the beginning without biopsy. Prednisone treatment ever seemed to be effective and antibiotics had no effect. Besides salivary involvement, the patient also manifested as testicle swelling and severe pancytopenia with the development of the disease, which rarely appeared in Mikulicz's disease. Physical examination showed skin, sclera yellow dye, swollen submandibular, sublingual and lacrimal gland and splenomegaly. As a result, biopsy of right submandibular gland was made, and mucosa-associated lymphoid tissue lymphoma was confirmed by morphology and immunohistochemistry. Bone marrow biopsy also confirmed that lymphoma cells were found in the bone marrow. Finally, the diagnosis of mucosa-associated lymphoid tissue lymphoma (Phase IVE, Group A) was made on the patient, who was transferred to the hematology department for the treatment. NHL, especially, primary extranodal lymphoma usually involves the salivary gland, and painless swelling of the salivary gland is a common manifestation, similar with Mikulicz's disease. So although salivary gland swelling is often associated with autoimmune diseases such as Sjogren's syndrome and IgG4-related disease, the awareness and suspicion of a possibility of NHL are essential for rheumatologists. Biopsy is a necessary examination to decrease or avoid misdiagnosis.
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Affiliation(s)
- A C Liu
- Department of Kidney, Peking University People's Hospital, Beijing 100044, China
| | - Y Chen
- Rehabilitation Centre for Chronic Disease, Taihe Hospital, Shiyan 442000, Hubei, China
| | - J S Jia
- Department of Hematology, Peking University People's Hospital, Beijing 100044, China
| | - S Y Gao
- Department of Pathology, Peking University People's Hospital, Beijing 100044, China
| | - Y Y Liu
- Department of Rheumatology and Immunology, Peking University People's Hospital, Beijing 100044, China
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Kuo WY, Huang CH, Liu AC, Cheng CP, Li SH, Chang WC, Weiss C, Azem A, Jinn TL. CHAPERONIN 20 mediates iron superoxide dismutase (FeSOD) activity independent of its co-chaperonin role in Arabidopsis chloroplasts. New Phytol 2013; 197:99-110. [PMID: 23057508 DOI: 10.1111/j.1469-8137.2012.04369.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 09/03/2012] [Indexed: 05/08/2023]
Abstract
Iron superoxide dismutases (FeSODs; FSDs) are primary antioxidant enzymes in Arabidopsis thaliana chloroplasts. The stromal FSD1 conferred the only detectable FeSOD activity, whereas the thylakoid membrane- and nucleoid-co-localized FSD2 and FSD3 double mutant showed arrested chloroplast development. FeSOD requires cofactor Fe for its activity, but its mechanism of activation is unclear. We used reversed-phase high-performance liquid chromatography (HPLC), gel filtration chromatography, LC-MS/MS, protoplast transient expression and virus-induced gene silencing (VIGS) analyses to identify and characterize a factor involved in FeSOD activation. We identified the chloroplast-localized co-chaperonin CHAPERONIN 20 (CPN20) as a mediator of FeSOD activation by direct interaction. The relationship between CPN20 and FeSOD was confirmed by in vitro experiments showing that CPN20 alone could enhance FSD1, FSD2 and FSD3 activity. The in vivo results showed that CPN20-overexpressing mutants and mutants with defective co-chaperonin activity increased FSD1 activity, without changing the chaperonin CPN60 protein level, and VIGS-induced downregulation of CPN20 also led to decreased FeSOD activity. Our findings reveal that CPN20 can mediate FeSOD activation in chloroplasts, a role independent of its known function in the chaperonin system.
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Affiliation(s)
- W Y Kuo
- Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
| | - C H Huang
- Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
| | - A C Liu
- Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
| | - C P Cheng
- Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
| | - S H Li
- Department of Medical Research, Mackay Memorial Hospital, Tamshui, 25160, Taiwan
| | - W C Chang
- Genomics Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - C Weiss
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978, Israel
| | - A Azem
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978, Israel
| | - T L Jinn
- Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
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Abstract
Valve interstitial cells (VIC) are the most prevalent cells in the heart valve, regulating to a large extent the normal biology of the valve and its pathobiological response to disease. In the process of valve tissue repair by VICs, single cell motility is likely to be important, as it is in wound repair by most mesenchymal type cells. We designed in vitro experiments using low density monolayer cultures to study the association of morphology and motility in single VICs which expressed alpha-smooth muscle actin. We observed that the morphology of single VICs can be categorized into six types which are reminiscent of the shape of VICs seen in vivo during valve repair. Of these morphologies, round, rhomboid, tailed and spindled shaped VICs were the most common. VICs did change their morphology over time. Rhomboid cells could become tailed or spindle-shaped and vice versa. Using time-lapse imaging and immunofluorescent microscopy, we showed that VIC morphologies reflect differences in cell motility and cell-matrix interactions. Tailed and spindle-shaped VICs were the predominant motile types and were associated with few extracellular fibronectin fibrils and less focal adhesions, as demonstrated by vinculin staining. Round and rhomboid shaped VICs were less motile and were associated with prominent vinculin and extracellular fibronectin fibrils. We found that cell mitosis is an important determinant of VIC migration. Many of the motile VICs were associated with mitosis as the daughter cells separated by migrating as tailed and spindle shaped cells. Thus cell morphology is an important determinant of VIC motility.
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Affiliation(s)
- A C Liu
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
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Liu AC, Friend CM. Evidence for facile and selective desulfurization: the reactions of 2,5-dihydrothiophene on molybdenum(110). J Am Chem Soc 2002. [DOI: 10.1021/ja00003a014] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [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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Chen DC, Zhan DZ, Cheng CW, Liu AC, Chen CH. Determination of urine catecholamines by capillary electrophoresis with dual-electrode amperometric detection. J Chromatogr B Biomed Sci Appl 2001; 750:33-9. [PMID: 11204221 DOI: 10.1016/s0378-4347(00)00388-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Demonstrated in this study is that without pretreatment and preconcentration nanomolar-level catecholamines in human urine samples can be quantitatively determined with ease by utilizing capillary electrophoresis coupled with amperometric detection. The detector employs a parallel-opposed dual-electrode scheme assembled with an on-capillary electrode and a disk electrode and takes advantage of the redox cycling of analytes between the two working electrodes to improve the limit of detection. The matrix effect of urine samples significantly decreases the detection sensitivity from that obtained in standard solutions. Therefore, calibration curves derived from standard solutions cannot be used in quantitative determination of catecholamines. Methods of standard addition and internal standard have been studied. The results suggest that isoproterenol is a good internal standard to facilitate the measurements of dopamine, epinephrine, and norepinephrine in human urine samples.
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Affiliation(s)
- D C Chen
- National Sun Yat-Sen University, Department of Chemistry, Kaohsiung, Taiwan.
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Yang PC, Kerr AB, Liu AC, Liang DH, Hardy C, Meyer CH, Macovski A, Pauly JM, Hu BS. New real-time interactive cardiac magnetic resonance imaging system complements echocardiography. J Am Coll Cardiol 1998; 32:2049-56. [PMID: 9857892 DOI: 10.1016/s0735-1097(98)00462-8] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES We conducted an initial clinical trial of a newly developed cardiac magnetic resonance imaging (CMRI) system. We evaluated left ventricular (LV) function in 85 patients to compare the clinical utility of the CMRI system with echocardiography, the current noninvasive gold standard. BACKGROUND Conventional CMRI systems require cardiac-gating and respiratory compensation to synthesize a single image from data acquired over multiple cardiac cycles. In contrast, the new CMRI system allows continuous real-time dynamic acquisition and display of any scan plane at 16 images/s without the need for cardiac gating or breath-holding. METHODS A conventional 1.5T Signa MRI Scanner (GE, Milwaukee, Wisconsin) was modified by the addition of an interactive workstation and a bus adapter. The new CMRI system underwent clinical trial by testing its ability to evaluate global and regional LV function. The first group (A) consisted of 31 patients with acceptable echocardiography image quality. The second group (B) consisted of 31 patients with suboptimal echocardiography image quality. The third group (C) consisted of 29 patients with severe lung disease or congenital cardiac malformation who frequently have suboptimal echo study. Two independent observers scored wall motion and image quality using the standard 16-segment model and rank-order analysis. RESULTS CMRI evaluation was complete in less than 15 min. In group A, no significant difference was found between ECHO and CMRI studies (p = NS). In group B, adequate visualization of wall segments was obtained 38% of the time using ECHO and 97% of the time using CMRI (p < 0.0001). When grouped into coronary segments, adequate visualization of at least one segment occurred in 18 of 30 patients (60%) with ECHO and in all 30 patients (100%) with CMRI (p < 0.0001). In group C, adequate visualization of the wall segments was obtained in 58% (CI 0.53-0.62) of the time using echocardiography and 99.7% (CI 0.99-1.0) of the time using CMRI (p < 0.0001). CONCLUSIONS The new CMRI system provides clinically reliable evaluation of LV function and complements suboptimal echocardiography. In comparison with the conventional CMRI, the new CMRI system significantly reduces scan time, patient discomfort and associated cost.
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Affiliation(s)
- P C Yang
- Department of Medicine, Stanford University, California 94305, USA.
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Liu AC. Use of cytochrome P450 and prolonged prothrombin time. Am Fam Physician 1998; 58:1070. [PMID: 9787274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Liu AC. Treatment of postmenopausal osteoporosis. N Engl J Med 1998; 339:202; author reply 203. [PMID: 9669920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Pureur D, Liu AC, Digonnet MJ, Kino GS. Absolute measurement of the second-order nonlinearity profile in poled silica. Opt Lett 1998; 23:588-590. [PMID: 18084585 DOI: 10.1364/ol.23.000588] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Measurement of the thin nonlinearity profile of poled silica by the Maker fringe technique has been impossible because of total internal reflection (TIR) at the back surface of the sample. We demonstrate that this limitation can be removed by placing a prism against each face of the sample, thus avoiding TIR. This novel technique allows, for the first time to our knowledge, the nonlinearity profile of a thin film to be inferred by the Maker fringe technique. Applied to a silica sample thermally poled under standard conditions (275 degrees C and 5.3 kV for 30 min), it suggests a Gaussian profile with a 1/e width of 8 mum and a maximum d(33) of 0.34 pm/V.
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Liu AC. Hepatotoxic reaction to chloroquine phosphate in a patient with previously unrecognized porphyria cutanea tarda. West J Med 1995; 162:548-51. [PMID: 7618323 PMCID: PMC1022841] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- A C Liu
- Palo Alto Medical Foundation, CA 94022, USA
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Liu AC, Byrne E. Cost of care for ambulatory patients with low back pain. J Fam Pract 1995; 40:449-455. [PMID: 7730768] [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: 05/21/2023]
Abstract
BACKGROUND Low back pain is a common presenting complaint in primary care, and the rate of utilization of resources among physicians treating this condition varies. Charges associated with the care of patients with low back pain were analyzed for a series of patients in a multispecialty group practice setting. METHODS One hundred seventy managed care patients were selected for review. Use of laboratory, plain radiography, magnetic resonance imaging (MRI), subspecialty referrals, and physical therapy was examined based on patient characteristics and physician specialty. Appropriateness of MRI and lumbar spine radiography according to published criteria was also studied. RESULTS Overall utilization was higher for patients who were referred to a subspecialist, and costs for visits to subspecialists were higher. Charges for physician services and MRI accounted for a majority of the total charges. Patients who were referred for subspecialty care or MRI but did not meet criteria for utilization of these resources comprised 6% of the study population but accounted for 27% of the total charges. Five of 14 patients undergoing MRI did not meet the published clinical criteria determining need for MRI, and 10 of 17 patients referred to subspecialists did not meet referral criteria. Other patients who met criteria for MRI or subspecialty consultation did not receive these services. Seventeen percent of the patients referred for physical therapy had a symptom duration of 2 weeks or less at the time of referral and accounted for 17% of all physical therapy charges. CONCLUSIONS The majority of costs associated with care for low back pain in this study were attributable to physician charges and the use of MRI. Charges for subspecialty physician services, lumbar spine radiographs, and MRI in patients not meeting appropriate criteria accounted for 19% of all costs.
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Affiliation(s)
- A C Liu
- Palo Alto Medical Foundation, Los Altos Center, CA 94022, USA
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Palabrica TM, Liu AC, Aronovitz MJ, Furie B, Lawn RM, Furie BC. Antifibrinolytic activity of apolipoprotein(a) in vivo: human apolipoprotein(a) transgenic mice are resistant to tissue plasminogen activator-mediated thrombolysis. Nat Med 1995; 1:256-9. [PMID: 7585043 DOI: 10.1038/nm0395-256] [Citation(s) in RCA: 110] [Impact Index Per Article: 3.8] [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: 01/26/2023]
Abstract
The extensive homology between apolipoprotein(a) and plasminogen has led to the hypothesis that the increased risk for atherosclerosis, cardiac disease and stroke associated with elevated levels of apolipoprotein(a) may reflect modulation of fibrinolysis. We have investigated the role of apolipoprotein(a) on clot lysis in transgenic mice expressing the human apolipoprotein(a) gene. These mice develop fatty streak lesions resembling early lesions of human atherosclerosis. Pulmonary emboli were generated in mice by injection, through the right jugular vein, of a human platelet-rich plasma clot radiolabelled with technetium-99m-labelled antifibrin antibodies. Tissue plasminogen activator was introduced continuously via the right jugular vein. Clot lysis, determined by ex vivo imaging, was depressed in mice carrying the apolipoprotein(a) transgene relative to their sex-matched normal littermates. These results directly demonstrate an in vivo effect of apolipoprotein(a) on fibrinolysis, an effect that may contribute to the pathology associated with elevated levels of this protein.
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Affiliation(s)
- T M Palabrica
- Division of Cardiology, New England Medical Center, Boston, Massachusetts 02111, USA
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Grainger DJ, Kemp PR, Metcalfe JC, Liu AC, Lawn RM, Williams NR, Grace AA, Schofield PM, Chauhan A. The serum concentration of active transforming growth factor-beta is severely depressed in advanced atherosclerosis. Nat Med 1995; 1:74-9. [PMID: 7584958 DOI: 10.1038/nm0195-74] [Citation(s) in RCA: 288] [Impact Index Per Article: 9.9] [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: 01/26/2023]
Abstract
Recent evidence has led us to propose that transforming growth factor-beta (TGF-beta) is a key inhibitor of atherosclerosis. We show here that a population of patients with advanced atherosclerosis all have less active TGF-beta in their sera than patients with normal coronary arteries, with a fivefold difference in average concentration between the two groups. This correlation with atherosclerosis is much stronger than for other known major risk factors and it may therefore have important diagnostic and prognostic significance. Aspirin medication correlates with an increase in active TGF-beta concentration, indicating that therapeutic interventions for TGF-beta are possible.
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Affiliation(s)
- D J Grainger
- Department of Biochemistry, University of Cambridge, UK
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Liu AC, Lawn RM, Verstuyft JG, Rubin EM. Human apolipoprotein A-I prevents atherosclerosis associated with apolipoprotein[a] in transgenic mice. J Lipid Res 1994. [DOI: 10.1016/s0022-2275(20)39932-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Liu AC, Lawn RM, Verstuyft JG, Rubin EM. Human apolipoprotein A-I prevents atherosclerosis associated with apolipoprotein[a] in transgenic mice. J Lipid Res 1994; 35:2263-7. [PMID: 7897323] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Elevated levels of apolipoprotein[a] (apo[a]) and apolipoprotein A-I (apoA-I) are associated, respectively, with increased and decreased atherosclerosis risk, in both humans and transgenic mice. To investigate the interactions of these two important lipid-associated proteins, we assessed the effect of expression of human apoA-I and apo[a] transgenes, both singularly and together, on murine atherogenesis. Mice expressing the apo[a] transgene have a lipoprotein profile similar to nontransgenic controls, yet have significantly increased susceptibility to diet-induced atherosclerosis. Compared to mice expressing only the apo[a] transgene, mice expressing both apo[a] and apoA-I transgenes have twofold greater high density lipoprotein (HDL) concentrations and approximately a 20-fold decrease in development of early atherosclerotic lesions. The finding of decreased atherosclerosis in the setting of elevated apo[a] and apoA-I suggests that elevations of apoA-I and HDL have a dominant effect in reducing atherosclerosis susceptibility in various settings, including those not associated with alterations of plasma lipids.
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Affiliation(s)
- A C Liu
- Human Genome Center, Lawrence Berkeley Laboratory, University of California, Berkeley 94720
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18
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Abstract
A HIGH concentration of serum lipoprotein(a) is a risk factor for atherosclerosis. Lipoprotein(a) consists of low-density lipoprotein with the additional protein component, apolipoprotein(a), a homologue of plasminogen. Lipoprotein(a) and apolipoprotein(a) enhance proliferation of human vascular smooth muscle cells (hVSMCs) in culture by inhibiting activation of plasminogen to plasmin, thus blocking the proteolytic activation of transforming growth factor-beta (TGF-beta), an autocrine inhibitor of hVSMC proliferation. The hypothesis that this pathway is a key step in atherogenesis is tested on transgenic mice expressing the human apolipoprotein(a) gene. We show here that the activation of TGF-beta is inhibited in the aortic wall and serum of mice expressing apolipoprotein(a), as a consequence of apolipoprotein(a) inhibition of plasminogen activation. These effects are closely correlated with VSMC activation.
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Affiliation(s)
- D J Grainger
- Department of Biochemistry, University of Cambridge, UK
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19
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Abstract
Lipoprotein (a) is a major inherited risk factor for vascular diseases, including coronary atherosclerosis, restenosis, and stroke. The pathologic mechanisms are uncertain, but are likely to involve the unique plasminogen-like component of this lipoprotein, apolipoprotein (a). Studies suggest that apolipoprotein (a) can enhance lipid deposition in vessel walls, interfere with fibrinolysis, modulate smooth muscle cell activity, and induce endothelial dysfunction. This review discusses the key concepts relating to these mechanisms, with emphasis on recent studies.
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Affiliation(s)
- A C Liu
- Cardiovascular Research Center, Stanford University School of Medicine, California
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20
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Liu AC, Heinrichs BS, Leach RM. Influence of manganese deficiency on the characteristics of proteoglycans of avian epiphyseal growth plate cartilage. Poult Sci 1994; 73:663-9. [PMID: 8047509 DOI: 10.3382/ps.0730663] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [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: 01/28/2023] Open
Abstract
The need for manganese for normal skeletal development appears to be related to its role in proteoglycan biosynthesis. The purpose of this research was to characterize the proteoglycans synthesized under conditions of manganese deficiency. The proteoglycans were extracted from epiphyseal growth plate cartilage and the monomers separated by cesium chloride density gradient centrifugation followed by column chromatography. The proteoglycan monomers from normal cartilage contained primarily (92%) chondroitin sulfate side chains with keratan sulfate being a minor (8%) component. Manganese deficiency reduced the total amount of cartilage proteoglycans. Of the monomers present in deficient cartilage, the majority (75%) were similar to those found in normal cartilage. Cartilage from deficient chicks also contained a second monomer fraction (25%) characterized by a reduced carbohydrate content. Thus, in addition to a reduction in total proteoglycan content, manganese deficiency results in qualitative changes in the proteoglycans present in epiphyseal growth plate cartilage.
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Affiliation(s)
- A C Liu
- Department of Poultry Science, Pennsylvania State University, University Park 16802
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Abstract
We report what is to our knowledge the first demonstration of electro-optic phase modulation in a fused-silica channel waveguide. The nonlinearity is induced through elevated temperature poling of an electron-beamirradiated waveguide. A phase shift of 32 mrad was measured at lambda = 633 nm for a device interaction length of 4.8 mm and an applied electric field of 7.3 V/microm.
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Wade DP, Clarke JG, Lindahl GE, Liu AC, Zysow BR, Meer K, Schwartz K, Lawn RM. Genetic influences on lipoprotein(a) concentration. Biochem Soc Trans 1993; 21:499-502. [PMID: 8359518 DOI: 10.1042/bst0210499] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- D P Wade
- Division of Cardiovascular Medicine, Stanford University School of Medicine, CA 94305-5246
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23
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Wade DP, Clarke JG, Lindahl GE, Liu AC, Zysow BR, Meer K, Schwartz K, Lawn RM. 5' control regions of the apolipoprotein(a) gene and members of the related plasminogen gene family. Proc Natl Acad Sci U S A 1993; 90:1369-73. [PMID: 7679504 PMCID: PMC45874 DOI: 10.1073/pnas.90.4.1369] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.1] [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: 01/26/2023] Open
Abstract
Elevated blood levels of apolipoprotein(a), the component of lipoprotein(a) that distinguishes it from low density lipoprotein, are a major risk factor for atherosclerosis. The apolipoprotein(a) gene is highly similar to the plasminogen gene and to at least four other genes or pseudogenes. The 5' untranslated and flanking sequences of these six genes contain extensive regions of near identity and share sequence elements involved in the initiation of transcription and translation. About 1000 base pairs of flanking DNA of each gene are sufficient to promote transcription in cultured hepatocytes. The apolipoprotein(a) gene promoter contains functional interleukin 6-responsive elements, consistent with the reported acute-phase response of apolipoprotein(a). Flanking genomic fragments of the apoliprotein(a) gene from two individuals with vastly different plasma apolipoprotein(a) concentrations have sequence differences that are reflected in differences in the rate of in vitro transcription.
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Affiliation(s)
- D P Wade
- Division of Cardiovascular Medicine, Stanford University School of Medicine, CA 94305-5246
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Abstract
Angiosarcomas of the face and scalp are aggressive, malignant neoplasms that are associated with a poor prognosis. Radiotherapy and chemotherapy alone have failed to give satisfactory results in the treatment of this disease, so surgery continues to play the major role in its management. In this article we report on 3 patients with angiosarcoma of the face and scalp recently seen in our institution. The clinical presentation, pathophysiology, and prognosis are extensively reviewed from the recent literature. We conclude with a discussion of treatment options in the management of this disease, with emphasis on surgical management.
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Affiliation(s)
- A C Liu
- Department of Medicine, Stanford University Medical Center, CA 94305
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Liu RG, Liu AC, Li L, Wang J. Elimination of wave in WPW syndrome by esophageal pacing. Chin Med J (Engl) 1989; 102:431-3. [PMID: 2512063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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Mocarski ES, Liu AC, Spaete RR. Structure and variability of the a sequence in the genome of human cytomegalovirus (Towne strain). J Gen Virol 1987; 68 ( Pt 8):2223-30. [PMID: 3039048 DOI: 10.1099/0022-1317-68-8-2223] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
We have defined the boundaries of the a sequence from human cytomegalovirus (CMV) strain Towne, characterized internal variability and determined the position of the cleavage site used to generate genomic termini. The cleavage site is positioned a fixed distance from two stretches of sequence homology that have been observed near the ends of many herpesvirus genomes. Unlike a comparable region in CMV (AD169), the CMV (Towne) a sequence has a relatively low level of variability within the a sequence and its structure is stable through repeated virus passage.
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Gephardt GN, Tubbs RR, Liu AC, Petras RE, Ahmad M, Golish JA, Tomashefski JF. Pulmonary lymphoid neoplasms. Role of immunohistology in the study of cellular immunotypes and in differential diagnosis. Chest 1986; 89:545-50. [PMID: 2937619 DOI: 10.1378/chest.89.4.545] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Seven cases of lymphoid neoplasms presenting in the lung were evaluated by immunohistology for T and B cell antigens and immunoglobulin light chains in frozen tissue sections. Although follow-up was short or inconclusive in some patients with lymphoma and pseudolymphoma, it was concluded that evaluation of T and B cell antigens and immunoglobulin light chains in frozen tissue is helpful in classifying lymphocytic neoplasms, especially in cases without definite cytologic evidence of malignancy. As demonstrated in two additional cases, lymphocyte/leukocyte markers in paraffin-embedded tissue are important in the differential diagnosis of lesions with cytologic features of malignancy.
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Abstract
We describe here a case of endotracheobronchial tuberculosis involving both the trachea and major bronchi. Endobronchial carcinoma was suspected initially, even at the time of bronchoscopy. Later, despite improvement of the pulmonary infiltrate and clinical symptoms after chemotherapy, upper airway obstruction occurred. Repeat bronchoscopy showed a distal tracheal nongranulomatous, fibrogranular stenotic lesion. Laser therapy was then employed to reduce the stenosis.
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Abstract
The regulation of glucose 6-phosphatase in hepatic microsomes by thyroid and corticosteroid hormones has been studied following the administration of 3,3',5-triiodo-L-thyronine and/or triamcinolone to hypophysectomized rats. The apparent Km for glucose-6-P in isolated ("intact") microsomes increased following administration of either hormone; there was little or no difference in the apparent Km when microsomes were treated with sodium deoxycholate ("disrupted"). In intact microsomes, triiodothyronine caused a 2.3-fold increase in the Vmax of glucose 6-phosphatase; triamcinolone, a 4-fold increase; and both hormones together, a 4.4-fold increase. Corresponding values for disrupted microsomes were: triiodothyronine, 3.7-fold; triamcinolone, 1.8-fold; both hormones, 3.3-fold. After triiodothyronine treatment, disruption of microsomes caused an over 5-fold increase in Vmax; after triamcinolone treatment, the increase was only 1.5-fold. This difference could not be explained by a change in the energy of activation of glucose 6-phosphatase in either intact or disrupted microsomes following hormone treatment. Glucose 6-phosphatase was localized by a cytochemical procedure; the reaction product was associated with 90% of the profiles in all microsomal preparations, except for those from triiodothyronine-treated rats, where less than 50% contained lead precipitate. Vesicles free of lead phosphate were isolated from sucrose gradients and accounted for less than 10% of the protein and glucose 6-phosphatase in all preparations, again except for those from triiodothyronine-treated rats, where they represented 40% of both the protein and glucose 6-phosphatase. The results are consistent with a model for glucose 6-phosphatase in which the substrate is transported across the microsomal membrane by a specific carrier before hydrolysis within the cisternae by a phosphohydrolase. It is suggested that the effect of triiodothyronine is mainly on the activity of the phosphohydrolase, and triamcinolone, on that of the carrier.
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Abstract
Fasting plasma cyclic adenosine monophosphate (cAMP) was measured in 50 mature-onset diabetic patients and in 111 non-diabetic patients. Methods used to determine plasma cAMP are described. The addition of sepharose agar beads to the bovine adrenocortical binding protein has considerably improved the sensitivity and simplified the radioligand-receptor assay of cAMP. No statistical differences in plasma cAMP were noted in relation to sex in either group, to the presence of diabetes mellitus or to age or weight in the non-diabetic patients. Plasma cGMP levels are now being studied to determine if these may prove better indicators of insulin activity than plasma cAMP.
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Abstract
Bilateral hypothalamic lesions were placed in the ventromedial nuclei of 15 male weanling rats. Nine male littermates were used as controls. Food intake, body weight, and nose-occipital (N-O) length were followed for 90 days. Rats were killed on the 90th postoperative day and stomach weight, body fat content, and femur length were then measured. Although the daily food intake and the rate of body weight gain of the rats with lesions were comparable to those of their controls, all 15 operated rats became obese and their N-O and femur lengths were significantly shorter. It is concluded that hypothalamic obesity of weanling rats is associated with growth impairment.
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Affiliation(s)
- A. C. Liu
- From the Laboratories of Physiology in the Harvard Medical School
| | - A. Rosenblueth
- From the Laboratories of Physiology in the Harvard Medical School
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Affiliation(s)
- A. C. Liu
- From the Laboratories of Physiology in the Harvard Medical School
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