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Hu X, Wang M, Fei X. Family quality of life of Chinese families of children with intellectual disabilities. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 2012; 56:30-44. [PMID: 21366752 DOI: 10.1111/j.1365-2788.2011.01391.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
BACKGROUND The concepts of quality of life and family quality of life (FQOL) are increasingly being studied in the field of intellectual disabilities (ID) in China as important frameworks for: (1) assessing families' need for supports and services; (2) guiding organisational and service delivery system changes; and (3) evaluating quality family outcomes. The present study focused on exploring the perceptions of Chinese families who have a child with an ID regarding FQOL as well as examining the factor structure of FQOL concept from Chinese families. METHODS The Chinese version of the Family Quality of Life Scale was used to survey Chinese families living in the urban and suburban areas of Beijing who have a child with ID. A total of 442 families participated in this study. Confirmatory factor analysis was used to test the factor structure of FQOL. Multivariate analysis was also used to examine group differences among families in terms of family demographic variables. RESULTS A five-factor structure of the FQOL construct was found in the Chinese sample, suggesting a similar factor structure found from US families in the literature. Different living conditions (e.g. housing and transportation) tended to affect significantly families' satisfaction ratings of their FQOL. It is also found that family income and severity of disability of the child are predictors of families' satisfaction ratings of FQOL. CONCLUSION The preliminary findings of this study suggest a cross-cultural factor structure comparability of FQOL between samples in the USA and China. Results call for further examination of the family-centred service and support as a mediator on the interactive relationship between family characteristics, family needs and FQOL outcomes.
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Shen Y, Wang Y, Sheng K, Fei X, Guo Q, Larner J, Kong X, Qiu Y, Mi J. Serine/threonine protein phosphatase 6 modulates the radiation sensitivity of glioblastoma. Cell Death Dis 2011; 2:e241. [PMID: 22158480 PMCID: PMC3252736 DOI: 10.1038/cddis.2011.126] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Increasing the sensitivity of glioblastoma cells to radiation is a promising approach to improve survival in patients with glioblastoma multiforme (GBM). This study aims to determine if serine/threonine phosphatase (protein phosphatase 6 (PP6)) is a molecular target for GBM radiosensitization treatment. The GBM orthotopic xenograft mice model was used in this study. Our data demonstrated that the protein level of PP6 catalytic subunit (PP6c) was upregulated in the GBM tissue from about 50% patients compared with the surrounding tissue or control tissue. Both the in vitro survival fraction of GBM cells and the patient survival time were highly correlated or inversely correlated with PP6c expression (R2=0.755 and −0.707, respectively). We also found that siRNA knockdown of PP6c reduced DNA-dependent protein kinase (DNA-PK) activity in three different GBM cell lines, increasing their sensitivity to radiation. In the orthotopic mice model, the overexpression of PP6c in GBM U87 cells attenuated the effect of radiation treatment, and reduced the survival time of mice compared with the control mice, while the PP6c knocking-down improved the effect of radiation treatment, and increased the survival time of mice. These findings demonstrate that PP6 regulates the sensitivity of GBM cells to radiation, and suggest small molecules disrupting or inhibiting PP6 association with DNA-PK is a potential radiosensitizer for GBM.
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Penna I, Du H, Fei X, Taylor H. P-543. Fertil Steril 2006. [DOI: 10.1016/j.fertnstert.2006.07.912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Araujo Penna I, Du H, Fei X, Ferriani R, Taylor H. O-73. Fertil Steril 2006. [DOI: 10.1016/j.fertnstert.2006.07.087] [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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Wietfeldt FE, Dewey MS, Gilliam DM, Nico JS, Fei X, Snow WM, Greene GL, Pauwels J, Eykens R, Lamberty A, Van Gestel J. Measurement of the Neutron Lifetime by Counting Trapped Protons. JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY 2005; 110:327-331. [PMID: 27308145 PMCID: PMC4852842 DOI: 10.6028/jres.110.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/11/2004] [Indexed: 06/06/2023]
Abstract
We measured the neutron decay lifetime by counting in-beam neutron decay recoil protons trapped in a quasi-Penning trap. The absolute neutron beam fluence was measured by capture in a thin (6)LiF foil detector with known efficiency. The combination of these measurements gives the neutron lifetime: τ n = (886.8 ± 1.2 ± 3.2) s, where the first (second) uncertainty is statistical (systematic) in nature. This is the most precise neutron lifetime determination to date using an in-beam method.
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Dewey MS, Gilliam DM, Nico JS, Wietfeldt FE, Fei X, Snow WM, Greene GL, Pauwels J, Eykens R, Lamberty A, Van Gestel J. Measurement of the neutron lifetime using a proton trap. PHYSICAL REVIEW LETTERS 2003; 91:152302. [PMID: 14611461 DOI: 10.1103/physrevlett.91.152302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2003] [Indexed: 05/24/2023]
Abstract
We report a new measurement of the neutron decay lifetime by the absolute counting of in-beam neutrons and their decay protons. Protons were confined in a quasi-Penning trap and counted with a silicon detector. The neutron beam fluence was measured by capture in a thin 6LiF foil detector with known absolute efficiency. The combination of these simultaneous measurements gives the neutron lifetime: tau(n)=(886.8+/-1.2[stat]+/-3.2[syst]) s. The systematic uncertainty is dominated by uncertainties in the mass of the 6LiF deposit and the 6Li(n,t) cross section. This is the most precise measurement of the neutron lifetime to date using an in-beam method.
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Wang P, Fei X. [A new compression method for ECG data]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 2001; 18:523-6. [PMID: 11791297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Due to the regularity of activity of the heart and similarity among each period of ECG signal, there is high correlation between DCT coefficients of every two frames of ECG data. Using this characteristic, we present a compression method for ECG data in this paper, by which we can get a higher compression ratio(CR) than the compression method just via DCT does.
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Fei X, Tan BK, Lee ST, Foo CL, Sun DF, Aw SE. Effect of fibrin glue coating on the formation of new cartilage. Transplant Proc 2000; 32:210-7. [PMID: 10701027 DOI: 10.1016/s0041-1345(99)00939-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Zhigang L, Xufu Y, Fei X, Xuemei P. Morphological changes of rats muscles at various postmortem intervals by scanning electron microscopy. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1999; 14:255-8. [PMID: 12894904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
The aim of this study was to observe the morphological changes of muscle in the process of rigor mortis. The quadriceps of 40 rats at various postmortem intervals were observed under the scanning electron microscope (SEM) and the light microscope by phosphotungstic acid-haematoxylin (PTAH) stain. The results showed that the striations of muscle were blurred within 4 h, but they became apparent from 6 h to 24 h after death. The authors suggest that this phenomenon be associated with the increased resistance of muscle against the postmortal changes. The observations by scanning electron microscopy and light microscopy have revealed that the muscles do contract in the process of rigor mortis because the distance between two Z lines shortens and the 1 band narrows, compared with those in anaesthetised animals. The basic biochemical process for the formation of rigor mortis is the same as that of muscle contraction except that the former happens postmortem and the latter antemortem.
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St John MA, Tao W, Fei X, Fukumoto R, Carcangiu ML, Brownstein DG, Parlow AF, McGrath J, Xu T. Mice deficient of Lats1 develop soft-tissue sarcomas, ovarian tumours and pituitary dysfunction. Nat Genet 1999; 21:182-6. [PMID: 9988269 DOI: 10.1038/5965] [Citation(s) in RCA: 344] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The lats gene has been identified as a tumour suppressor in Drosophila melanogaster using mosaic screens. Mosaic flies carrying somatic cells that are mutant for lats develop large tumours in many organs. The human LATS1 homologue rescues embryonic lethality and inhibits tumour growth in lats mutant flies, demonstrating the functional conservation of this gene. Biochemical and genetic analyses have revealed that LATS1 functions as a negative regulator of CDC2 (ref. 3). These data suggest that mammalian LATS1 may have a role in tumorigenesis. To elucidate the function of mammalian LATS1, we have generated Lats1-/- mice. Lats1-/- animals exhibit a lack of mammary gland development, infertility and growth retardation. Accompanying these defects are hyperplastic changes in the pituitary and decreased serum hormone levels. The reproductive hormone defects of Lats1-/- mice are reminiscent of isolated LH-hypogonadotropic hypogonadism and corpus luteum insufficiency in humans. Furthermore, Lats1-/- mice develop soft-tissue sarcomas and ovarian stromal cell tumours and are highly sensitive to carcinogenic treatments. Our data demonstrate a role for Lats1 in mammalian tumorigenesis and specific endocrine dysfunction.
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Boshier MG, Dhawan S, Fei X, Hughes VW, Janousch M, Jungmann K, Liu W, Pillai C, Prigl R, Putlitz G, Reinhard I, Schwarz W, Souder PA, Wang X, Woodle KA, Xu Q. Observation of resonance line narrowing for old muonium. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1995; 52:1948-1953. [PMID: 9912452 DOI: 10.1103/physreva.52.1948] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Chen SF, Fei X, Li SH. A new simple method for isolation of microvascular endothelial cells avoiding both chemical and mechanical injuries. Microvasc Res 1995; 50:119-28. [PMID: 7476573 DOI: 10.1006/mvre.1995.1044] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Our study indicates that when small pieces of lung or muscles of chest wall are cultured, erythrocytes and leukocytes (PMNs) leave the tissues first, followed by vascular endothelial cells (ECs). Fibroblasts and other mixed cells grow after 72 hr culture. The ECs can then be isolated avoiding mechanical and chemical injuries. The lung tissue is obtained from the peripheral surface and muscles from the chest. It is then cut into pieces and cultured with DMEM containing 20% fetal bovine serum. After 60 hr culture, the tissues are discarded. The flask contains only ECs and blood cells. Blood cells can be cleared out after the cells are subcultured once or twice. The primary cells and the subcultured cells cultured on gelatinized culture dish give the capillary-like structure. Cells cultured on untreated dishes have regular cobblestone morphology and junctional contacts. The isolated cells were not mesothelial cells because the cells did not react to antibody against cytokeratin 18, while mesothelial cells reacted strongly to the antibody. The cells can be isolated from the lung tissue without pleura. The primary microvascular ECs are also cultured on microcarriers (cytodex 3). Because both mechanical and proteolytic injuries are avoided, the cells may be more similar to cells in the in vivo state. There are no significant differences in PMN-endothelium adherence and monolayer responses to second messengers, platelet activating factor, and phospholipase A2 when pulmonary and muscular microvascular endothelial cells are compared.
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Chi H, Fei X, Lai C. [Effect of interferon on filtering blebs after trabeculectomy in rabbit eyes]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 1995; 31:218-20. [PMID: 7555408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A study on the suppressive effect of interferon on the formation of filtering surgical scar was carried out. Trabeculectomy was performed on 6 rabbit eyes. 100,000 Units of interferon were subconjunctivally injected at the filtering bleb during the operation and on the 3rd and 7th post-operative day. The filtering blebs, filtering function and the scanning electron microscopic examinations of the surgical areas of the walls of the globes were observed. The results show that interferon can reduce the scar, improve filtering function and can be tried clinically.
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Fei X, Lee ST. Growth of human corneal endothelial cells in vitro. Transplant Proc 1994; 26:3403. [PMID: 7998192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Fei X, Lee ST, Tseng PS, Leung CM. Transplantation of cultured corneal endothelium in rabbits. Transplant Proc 1994; 26:3404. [PMID: 7998193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Li SH, Fei X, Chen SF, Ding ZQ, Wu ZL. Pentoxifylline attenuates platelet activating factor-induced permeable edema in isolated perfused guinea pig lungs. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1994; 15:219-22. [PMID: 7976374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The effect of pentoxifylline (Pen) on platelet activating factor (PAF)-induced pulmonary injury was studied in isolated guinea pig lungs perfused with cell-free Tris buffered Ringer solution. PAF (1.0 nmol.L-1) increased lung weight and pulmonary filtration coefficient (Kf), which indicated the formation of high permeable pulmonary edema. Pen (0.5 and 1.0 mmol.L-1) markedly attenuated the PAF-induced increment of lung weight and vascular permeability, but not the increment of pulmonary capillary pressure and venous resistance. There was no correlation between the severity of lung edema and the number of leukocytes in the perfusates. These results suggest that Pen has direct anti-permeability effect on pulmonary microvessels.
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Fei X. Magnetic moment of the negative muon. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1994; 49:1470-1472. [PMID: 9910379 DOI: 10.1103/physreva.49.1470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Fei X. Electric charges of positive and negative muons. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1994; 49:1467-1469. [PMID: 9910378 DOI: 10.1103/physreva.49.1467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Nordlund M, Hong D, Fei X, Ratner N. Schwann cells and cells in the oligodendrocyte lineage proliferate in response to a 50,000 dalton membrane-associated mitogen present in developing brain. Glia 1992; 5:182-92. [PMID: 1534065 DOI: 10.1002/glia.440050304] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The neuronal cell surface is believed to carry a mitogenic signal for peripheral glial cells. We have purified a mitogen from fetal bovine brain membranes that, in common with the PNS neuronal mitogen, stimulates the proliferation of Schwann cells in vitro and binds heparin. The purified mitogen has an apparent molecular weight of 50,000 daltons as estimated by elution of activity from non-reducing polyacrylamide gels. Since the developing central nervous system is a rich source of mitogen, we tested whether the protein is mitogenic for one or more cell types isolated from the developing brain. Purified mitogen was added to enriched cultures of astrocytes or developing oligodendrocytes, or to microglial cells. The analyses demonstrated that the protein is mitogenic for developing oligodendrocytes but not astrocytes or microglial cells. These results suggest that during development a membrane-associated mitogen present in the brain might regulate the proliferation of developing oligodendrocytes, and consequently, the population size of oligodendrocytes in the brain.
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Fei X, Seah CS, Lee ST. Human keratinocyte cell culture for the burns patients--a preliminary report. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 1991; 20:493-7. [PMID: 1799263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
One of the major problems in extensive burns is the relative lack of available donor sites for skin grafting. Keratinocyte cell culture in the laboratory was carried out successfully in Singapore General Hospital and shows promise as an alternative source for skin replacement. Our experience further proved that a fibroblast base is necessary for keratinocyte cell culture. It is observed that heterogenous cell source can grow concurrently and become confluent. The colony forming efficiency from trypsinized skin is about 1-4% in primary cultures and 35-40% in secondary cultures. The time taken to reach confluency are 20-21 days and 10-12 days respectively. The thickness of cultured skin is estimated as 0.5 mm (5-6 layers) under light microscope. The size of the harvested cultured skin is approximately one third of the cultured area due to contraction. The expansion ratio before shrinkage is estimated to be approximately 6000-fold based on our data.
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Gabrielse G, Fei X, Orozco LA, Tjoelker RL, Haas J, Kalinowsky H, Trainor TA, Kells W. Thousandfold improvement in the measured antiproton mass. PHYSICAL REVIEW LETTERS 1990; 65:1317-1320. [PMID: 10042233 DOI: 10.1103/physrevlett.65.1317] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Li SH, Gong XQ, Fei X, Wu ZL. Effects of platelet-activating factor on rat mesenteric microcirculation. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1990; 11:344-6. [PMID: 2104488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The actions of platelet-activating factor (PAF) on rat mesenteric microcirculation were studied by laser Doppler microscopy in vivo. PAF 0.2 -0.6 micrograms/kg iv produced a dose-related decrease in the blood flow velocity and an increase in the diameters of the mesenteric arterioles and venules. These responses were completely reversed by pretreatment with PAF receptor antagonist SRI 63441. The results suggest that PAF may be a mediator of microcirculatory disturbances in the disease conditions associated with excessive PAF release.
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Chen SF, Li SH, Fei X, Wu ZL. Phospholipase A2-induced lung edema and its mechanism in isolated perfused guinea pig lung. Inflammation 1990; 14:267-73. [PMID: 2361733 DOI: 10.1007/bf00915811] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Lung injury induced by phospholipase A2 (PLA2, 0.046 IU/ml perfusate) was studied in a continuous weighing system of isolated perfused guinea pig lungs. The results revealed that lung weight increased progressively during the 30-min perfusion of PLA2. No change of pulmonary arterial pressure was observed in the same period. Albumin permeability-surface area product, lung index, lung water content, exudate from pleura, and angiotensin-converting-enzyme activity increased significantly at the end of 30 min PLA2 perfusion. p-Bromophenacyl bromide, a PLA2 inhibitor, may block the above changes nearly completely. The effects of inhibitors of cyclooxygenase (indomethacin, IM), lipoxygenase (diethylcarbamaxine, DE), and platelet-activating factor (SRI 63-441) on PLA2-induced lung injury were also studied. We found: (1) PLA2 may induce high permeability lung edema. The role of endothelial injury in the permeability change remains to be further investigated. (2) DE ameliorated lung injury significantly within 10 min of PLA2 treatment but showed no effect after 15 min. IM ameliorated lung injury during the whole experimental period. SRI 63-441 had no effect. It is suggested that PLA2 may damage lung by inducing products of cyclooxygenase and lipoxygenase besides its direct effect.
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Li SH, Fei X, Wu ZL, Cheng SF. [Effect of an extract from the cauline of Piper kadsura ohwi on endotoxin-induced hypotension and lung injury in rats]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1989; 14:683-5, 704. [PMID: 2619897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Arterial hypotension and high-permeability pulmonary edema were induced by intravenous injection of platelet activating factor (PAF) or endotoxin in rats. Pre-treatment with extract from the Cauline of Piper kadsura attenuated endotoxin-induced hypotension and lung injury, which may result from the PAF antagonistic effect of Piper kadsura.
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Gabrielse G, Fei X, Orozco LA, Tjoelker RL, Haas J, Kalinowsky H, Trainor TA, Kells W. Cooling and slowing of trapped antiprotons below 100 meV. PHYSICAL REVIEW LETTERS 1989; 63:1360-1363. [PMID: 10040547 DOI: 10.1103/physrevlett.63.1360] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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