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Xiao DZ, Dai B, Chen J, Luo Q, Liu XY, Lin QX, Li XH, Huang W, Yu XY. Loss of macrophage migration inhibitory factor impairs the growth properties of human HeLa cervical cancer cells. Cell Prolif 2011; 44:582-90. [PMID: 21991924 DOI: 10.1111/j.1365-2184.2011.00787.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
OBJECTIVES This study aims to determine the role of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine associated with cell proliferation and tumour growth in vivo. MATERIALS AND METHODS Our team used RNA interference technology to knock down MIF expression in human HeLa cervical cancer cells and to establish a stable cell line lacking MIF function. RESULTS Our results showed that long-term loss of MIF had little effect on cell morphology, but significantly inhibited their population growth and proliferation. The HeLa MIF-knockdown cells retained normal apoptotic signalling pathways in response to TNF-alpha treatment; however, they exhibited unique DNA profiles following doxorubicin treatment, suggesting that MIF may regulate a cell cycle checkpoint upon DNA damage. Our data also showed that knockdown of MIF expression in HeLa cells led to increased cell adhesion and therefore impaired their migratory capacity. More importantly, cells lacking MIF failed to either proliferate in soft agar or form tumours in vivo, when administered to nude mice. CONCLUSION MIF plays a pivotal role in proliferation and tumourigenesis of human HeLa cervical carcinoma cells, and may represent a promising therapeutic target for cancer intervention.
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152
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Yu JL, Yang S, Luo Q, Wang HL, Wang B, Qu YY, Xu K. Endovascular treatment of intracranial ruptured aneurysms associated with arteriovenous malformations: a clinical analysis of 14 hemorrhagic cases. Interv Neuroradiol 2011; 17:78-86. [PMID: 21561563 DOI: 10.1177/159101991101700113] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 12/24/2010] [Indexed: 11/16/2022] Open
Abstract
This study investigated and summarized endovascular therapeutic strategies for intracranial ruptured aneurysms associated with arteriovenous malformations (AVMs). Between June 2005 and June 2009, we identified 16 aneurysms in 14 hemorrhagic cases of intracranial AVM using digital subtraction angiography (DSA). Of the 16 aneurysms, 14 were ruptured and two were unruptured. Aneurysms were classified as types I to IV, and were treated. Aneurysm treatment was followed by AVM treatment via various therapies, including embolization, gamma knife radiotherapy, or follow-up and observation to reduce the risk of aneurysm rupture or intracranial hemorrhage. Over a follow-up period ranging from six months to one year, none of the patients had aneurysm ruptures or intracranial hemorrhage. Most (13/14) patients had a Glasgow Outcome Scale (GOS) score of 5, and one patient had a score of 4. Sixteen aneurysms were treated successfully, as confirmed by DSA examination, and no AVMs re-grew. Clinical therapeutic strategies for intracranial ruptured aneurysms associated with AVMs should include aneurysm treatment first to reduce the risk of rupture and intracranial hemorrhage, eventually leading to a better prognosis.
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153
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Wang Y, Xu N, Luo Q, Li Y, Sun L, Wang H, Xu K, Wang B, Zhen Y. In vivo assessment of chitosan/β-glycerophosphate as a new liquid embolic agent. Interv Neuroradiol 2011; 17:87-92. [PMID: 21561564 DOI: 10.1177/159101991101700114] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Accepted: 01/13/2011] [Indexed: 11/15/2022] Open
Abstract
We sought to assess the feasibility of using thermosensitive chitosan/β-glycerophosphate forembolotherapy. The renal arteries in nine rabbits were embolized with chitosan/β-glycero-phosphate. The animals were studied angiographically and sacrificed at one week (n = 3), four weeks (n = 3), and eight weeks (n = 3) after embolotherapy. Histology was obtained at these three time points. Delivery of chitosan/β-glycerophosphate was successful in all cases. Complete occlusion was achieved in all cases. No recanalization was observed in the follow-up angiograms. No untoward inflammatory reactions were observed in the target renal arteries and infarcted kidneys during the histological examinations. Our preliminary feasibility evaluation in rabbit renal arteries indicates that C/GP is a satisfactory embolization agent.
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154
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Huang RM, He JY, Zhao J, Luo Q, Huang CM. Fenton-biological treatment of reverse osmosis membrane concentrate from a metal plating wastewater recycle system. ENVIRONMENTAL TECHNOLOGY 2011; 32:515-522. [PMID: 21877532 DOI: 10.1080/09593330.2010.504747] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Although reverse osmosis (RO) has been widely used in the recycling of metal plating wastewater, organic compounds and heavy metals in the RO concentrate are difficult to remove by conventional treatment. A combination process including Fenton oxidation and a biological aerated filter was used to treat RO concentrate containing complex Cu and Ni from metal plating. During the Fenton treatment, Cu and Ni ions were released due to degradation of organic compounds and then removed by pH adjustment and coagulation. The concentrate was further treated using by a biological aerated filter. Optimum conditions were as follows: initial pH of influent of 4.0; dosage of H2O2 of 5.0 mmol l(-1); ratio of n(Fe2+)/n(H2O2) of 0.8; precipitation pH of Cu and Ni ions of 8.0; and a hydraulic retention time of the biological aerated filter of 2.5 h. The results showed that concentrations of effluent COD, Cu and Ni ions were less than 40 mg l(-1), 0.5 mg l(-1) and 0.3 mg l(-1), respectively; this means the treated effluent meets the emission standards for pollutants from electroplating set by China's Environmental Protection Agency.
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155
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Chen E, Lin Y, Xiong H, Luo Q, Ma H. Exploiting probabilistic topic models to improve text categorization under class imbalance. Inf Process Manag 2011. [DOI: 10.1016/j.ipm.2010.07.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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156
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Yu JL, Wang HL, Xu N, Xu K, Wang B, Luo Q. Endovascular treatment of aneurysms arising from the basilar artery trunk and branches. Interv Neuroradiol 2010; 16:369-83. [PMID: 21162767 DOI: 10.1177/159101991001600403] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 08/08/2010] [Indexed: 12/23/2022] Open
Abstract
This study reports our experience with the endovascular treatment of basilar artery (BA) trunk and branch aneurysms. Subjects included 16 patients with BA trunk and branch aneurysms who underwent endovascular treatment in our hospital from October 2000 to October 2009, including four patients with associated arteriovenous malformation (AVM), two with associated moyamoya disease, one with multiple aneurysms at adjacent sites, and one with a distant aneurysm. Endovascular coil embolization, together with stent or balloon assistance when necessary, or while occluding the parent artery was performed. Associated diseases were managed intraoperatively or in the second stage, or treated with gamma knife radiotherapy, or followed up. Two patients with unsuccessful embolization died of re-rupture at the fourth month and fifth month follow-up. The remaining 14 patients reported good outcomes and experienced no re-rupture of either the aneurysm or associated disease. Angiographic follow-ups were conducted for the 14 patients for six to 12 months. Digital subtraction angiography (DSA) examination at the last follow-up showed no recurrence of the BA trunk and branch aneurysms. Together, BA trunk and branch aneurysms should be actively managed via endovascular techniques to prevent serious consequences due to aneurysm rupture and bleeding. Favorable outcomes can be obtained by the proper selection of endovascular treatment regimens.
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157
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Yang S, Yu JL, Wang HL, Wang B, Luo Q. Endovascular embolization of distal anterior choroidal artery aneurysms associated with moyamoya disease. A report of two cases and a literature review. Interv Neuroradiol 2010; 16:433-41. [PMID: 21162774 DOI: 10.1177/159101991001600410] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Accepted: 09/26/2010] [Indexed: 11/16/2022] Open
Abstract
We evaluated the feasibility of endovascular embolization for the management of distal anterior choroidal artery (AChA) aneurysms associated with moyamoya disease and performed a literature review to summarize their clinical features and treatment. We describe two cases of moyamoya disease-associated distal AChA aneurysms treated by endovascular embolization. In both cases, a good outcome was observed. We performed a MEDLINE (1980-2010) search which identified 13 similar cases. Our analysis of the clinical data from these 15 cases led us to conclude that (i) endovascular embolization is an effective and feasible treatment for distal AChA aneurysms associated with moyamoya disease; (ii) aneurysm location and the preservation of the parent artery are two major prognostic factors for moyamoya disease-associated distal AChA aneurysms subjected to craniotomy or endovascular therapy; (iii) the parent artery should be preserved when the aneurysm is located in the temporal horn of the lateral ventricle, but sacrificed when it is located in the trigone of the lateral ventricle.
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158
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Yu JL, Wang HL, Xu K, Li Y, Luo Q. Endovascular treatment of intracranial aneurysms associated with moyamoya disease or moyamoya syndrome. Interv Neuroradiol 2010; 16:240-8. [PMID: 20977854 DOI: 10.1177/159101991001600302] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Accepted: 10/04/2010] [Indexed: 11/17/2022] Open
Abstract
Direct surgical clipping proves to be difficult and dangerous for intracranial aneurysms associated with moyamoya disease (MMD) or moyamoya syndrome (MMS). This study presents our clinical experience of endovascular embolization of intracranial aneurysms associated with these diseases. A total of 13 cases of intracranial aneurysms associated with MMD or MMS were treated by endovascular embolization between January 2001 and January 2009. Patients were divided into two groups: a saccular aneurysm group (n=10) and a pseudoaneurysm group (n=3). Different endovascular therapeutic strategies were employed for each type of case. Of the 13 cases, 11 received successful endovascular embolization and had an uneventful postoperative course during one to two years of follow-up. However, endovascular embolization failed in the other two cases, of whom one died from rebleeding after the five-month follow-up, while the other was conservatively treated and experienced no rebleeding during the two-year follow-up. A favorable prognosis may be secured through careful selection of endovascular treatment regimens for patients with intracranial aneurysms associated with MMD or MMS according to the site of intracranial aneurysms.
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Yu JL, Xu K, Wang HL, Wang B, Luo Q. Microsurgical clipping of intracranial aneurysms following unsuccessful endovascular treatment. Analysis of ten cases. Interv Neuroradiol 2010; 16:23-30. [PMID: 20377976 DOI: 10.1177/159101991001600103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Accepted: 01/30/2010] [Indexed: 11/15/2022] Open
Abstract
The purpose of the current study was to examine the reasons for failed endovascular aneurysm coiling and to determine the outcome of immediate microsurgical clipping. From July 2006 to July 2008, 198 patients underwent endovascular coiling at our institute; among them, ten cases were unsuccessful. All of the patients were diagnosed with intracranial aneurysms (ICAs) by cranial computed tomography angiography (CTA), and all underwent endovascular treatment without digital subtraction angiography (DSA). When endovascular coiling failed, the patients were immediately transferred to the operating room for microsurgical clipping under the same anesthetic. The ten patients were divided into three groups based on the cause of endovascular failure and associated clinical features. The clinical follow-up period was between 6-12 months, and all 10 patients had good outcomes following the surgery. Taken together, the results of this study suggest that immediate microsurgical clipping after failed endovascular coiling is efficient and may provide improved outcomes by preventing rebleeding.
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160
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Ding G, Wang F, Huang H, Sheng J, Luo Q, Lv P. Intergenerational transmission of glucose intolerance associated with gestational diabetes mellitus. Fertil Steril 2009. [DOI: 10.1016/j.fertnstert.2009.07.1438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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161
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Luo Q, Cheng X, Holroyd T, Majestic C, Schechter J, Blair RJR. Emotional automaticity? It is a matter of timing --- spatiotemporal dynamics of the amygdala in the gamma band. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)72013-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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162
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163
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Zhai G, Buckle C, Chen C, Luo Q, Gao J. Re-investigation of human hypothalamic responses to oral water ingestion using fMRI. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)71598-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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164
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Zhang K, Yi B, Wang X, Li Z, Liang C, Luo Q, Wang X. Primary study of the long-term stability of maxillary distraction with rigid external distractor. Int J Oral Maxillofac Surg 2009. [DOI: 10.1016/j.ijom.2009.03.221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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165
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Zhang XB, Wei SC, Li CX, Xu X, He YQ, Luo Q, Li J, Wang YF. Mutation ofGJB2in a Chinese patient with keratitis-ichthyosis-deafness syndrome and brain malformation. Clin Exp Dermatol 2009; 34:309-13. [DOI: 10.1111/j.1365-2230.2008.02934.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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166
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Xu N, Wang H, Luo Q. Endovascular Treatment of Intracranial Wide-Necked Aneurysms with GDCs Combined with Balloon or Stent. Neuroradiol J 2009; 22:86-91. [PMID: 24206957 DOI: 10.1177/197140090902200113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2008] [Accepted: 01/03/2009] [Indexed: 11/16/2022] Open
Abstract
This article introduces our experience in embolizing wide-necked intracranial aneurysms with GDCs combined with balloon or stent. Fifty-five patients with wide-necked intracranial aneurysms (aneurysm neck ranged 2.1-7.0 mm, body/neck ≤2) underwent embolizing treatment with GDCs combined with balloon or stent. Twenty patients were treated with balloon technique. Only one complication occurred when one loop of a coil herniated into the parent artery after the GDC were detached, but no parent artery obstruction occurred. One patient died because from aneurysm rupture caused by herniation of the balloon through the over wide neck into the aneurysm during inflating. Thirty-five patients were treated with the stent technique. Five aneurysms were treated using a stent alone. Two of the five aneurysms could not be recognized from DSA after the stents were released (three and six month follow-ups showed no recurrence), one of the five ruptured leading to the patient's death two weeks after the operation. There was no aneurysm recurrence seen by DSA in the post operative follow-up of six to 12 months. GDCs combined with balloon or stent techniques are safe and effective in treatment of wide-necked intracranial aneurysms.
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167
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Wang Y, Feng D, Liu G, Luo Q, Xu Y, Lin S, Fei J, Xu L. γ-Aminobutyric acid transpoter 1 negatively regulates T cell-mediated immune responses and ameliorates autoimmune inflammation in the CNS. THE JOURNAL OF IMMUNOLOGY 2009. [DOI: 10.4049/jimmunol.182.3.1772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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168
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Ding GL, Chen XJ, Luo Q, Dong MY, Wang N, Huang HF. Peritoneal fluids with endometriosis inhibit the development of preimplantation mouse embryos and affect the concentration of EGF and IGF-I in the culture medium. Fertil Steril 2008. [DOI: 10.1016/j.fertnstert.2008.07.947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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169
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Pan H, Luo Q, Huang HF. 17ß-estradiol-induced human endometrial stromal cell invasion is dependent on c-fos-mediated matrix metalloproteinase-9 expression. Fertil Steril 2008. [DOI: 10.1016/j.fertnstert.2008.07.949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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170
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Ma YC, Zuo L, Chen JH, Luo Q, Yu XQ, Li Y, Xu JS, Huang SM, Wang LN, Huang W, Wang M, Xu GB, Wang HY. Improved GFR estimation by combined creatinine and cystatin C measurements. Kidney Int 2007; 72:1535-42. [PMID: 17898698 DOI: 10.1038/sj.ki.5002566] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Plasma creatinine may not reflect glomerular filtration rate (GFR) especially in the early stages of chronic kidney disease (CKD). Plasma cystatin C (cysC), however, has the potential to more accurately determine early GFR reduction. We sought to improve the creatinine-based GFR estimation by including cysC measurements. We derived a reference GFR from standard dual plasma sampling (99m)Tc-DTPA clearance in a training cohort of 376 randomly selected adult Chinese patients with CKD. We compared reference values to estimated GFR and applied multiple regression models to one equation based solely on cysC, and to another combining plasma creatinine (Pcr) and cysC measurements of the training cohort. The results were validated by testing an additional 191 patients. The difference, precision, and accuracy of the two estimates were compared with the modified Modification of Diet in Renal Disease (MDRD) equation for Chinese patients, and another estimate combining cysC and modified MDRD calculations. The estimated GFR combining Pcr and cysC measurements more accurately matched the reference GFR at all stages of CKD than the other equations, particularly in patients with near-normal kidney function.
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171
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Jin M, Cai J, Lu X, Luo Q, Huang H. Abnormal protein expression profiles in human ovaries from polycystic ovary syndrome patients. Fertil Steril 2007. [DOI: 10.1016/j.fertnstert.2007.07.630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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172
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Wong MH, Wu SC, Deng WJ, Yu XZ, Luo Q, Leung AOW, Wong CSC, Luksemburg WJ, Wong AS. Export of toxic chemicals - a review of the case of uncontrolled electronic-waste recycling. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2007; 149:131-40. [PMID: 17412468 DOI: 10.1016/j.envpol.2007.01.044] [Citation(s) in RCA: 403] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Revised: 12/20/2006] [Accepted: 01/06/2007] [Indexed: 05/14/2023]
Abstract
This paper reviews the concentrations of persistent organic pollutants such as flame retardants (PBDEs), dioxins/furans (PCDD/Fs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metals/metalloid concentrations of different environmental media at Guiyu, a traditional rice-growing village located in southeastern Guangdong Province (PR China), which has turned into an intensive electronic-waste (e-waste) recycling site. Incomplete combustion of e-waste in open air and dumping of processed materials are the major sources of various toxic chemicals. By comparing with existing data available in other areas and also guidelines adopted in different countries, it is obvious that the environment is highly contaminated by these toxic chemicals derived from the recycling processes. For example, the monthly concentration of the sum of 22 PBDE congeners contained in PM(2.5) (16.8ngm(-3)) of air samples at Guiyu was 100 times higher than published data. In order to safeguard the environment and human health, detailed investigations are urgently needed, especially on tracking the exposure pathways of different toxic chemicals which may affect the workers and local residents especially mothers, infants and children.
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173
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Mitchell DGV, Luo Q, Mondillo K, Vythilingam M, Finger EC, Blair RJR. The interference of operant task performance by emotional distracters: an antagonistic relationship between the amygdala and frontoparietal cortices. Neuroimage 2007; 40:859-868. [PMID: 18234519 DOI: 10.1016/j.neuroimage.2007.08.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2006] [Revised: 07/10/2007] [Accepted: 08/07/2007] [Indexed: 10/22/2022] Open
Abstract
This fMRI study investigates neural activity associated with the interfering effects of emotional distracters. While in the scanner, participants made simple motor responses to target stimuli that were preceded and followed by positive, negative, or neutral images. Despite instructions to disregard the pictorial images, participants were slower to respond in the presence of positive or negative relative to neutral distracters, and significantly slower for negative relative to positive distracters. Enhanced activity in the amygdala and visual cortex was evident during trials that included positive and negative distracters. In contrast, increased activity in inferior frontal gyrus (BA 47) was only observed during trials that involved negative distracters. Connectivity analysis showed that activity in right amygdala correlated with activity in cingulate gyrus, posterior cingulate, middle temporal cortex, and was negatively correlated with activity in lateral superior frontal gyrus, middle frontal/orbital gyrus, and parietal cortex. The pattern of neural activity observed was interpreted within the framework of current cognitive models of attention. During a task demonstrating behavioural interference in the context of emotional distracters, increased activity in neural regions implicated in emotional processing (the amygdala) was associated with reduced activity in regions thought to be involved in exerting attentional control over task-relevant sensory representations (a frontoparietal network).
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174
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Chu D, Luo Q, Li C, Gao Y, Yu L, Wei W, Wu Q, Shen J. Paeoniflorin inhibits TGF-beta1-mediated collagen production by Schistosoma japonicum soluble egg antigen in vitro. Parasitology 2007; 134:1611-21. [PMID: 17524166 DOI: 10.1017/s0031182007002946] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The main pathological characteristics of hepatic fibrosis in schistosomiasis are the proliferation of hepatic stellate cells (HSCs) and the deposition of collagen type I (Col I) and collagen type III (Col III). Transforming growth factor beta-1 (TGF-beta1) plays an important role in hepatic fibrosis. Paeoniflorin (PAE) has been reported to have immunoregulatory effects; however, the mechanism of its anti-hepatic fibrosis in S. japonicum has not been elucidated. In the present study, we found that mouse peritoneal macrophages (PMphis) stimulated by soluble egg antigen (SEA) of S. japonicum could secrete TGF-beta1, and the TGF-beta1 in the peritoneal macrophage-conditioned medium (PMCM) could induce proliferation of HSCs and secretion of Col I and III. We selected PMCM at 1 : 2 dilution as the optimum PMCM (OPMCM). Then we treated HSCs pre-incubated with OPMCM with PAE, and found that the inhibition of HSC proliferation or Col I and III production were closely correlated with the concentration of PAE. Further investigation found that PAE significantly decreased the Smad3 transcription and phosphorylation in HSCs stimulated by OPMCM. In conclusion, SEA plays a key role in hepatic fibrosis by inducing TGF-beta1 from PMphis. PAE can exert anti-fibrogenic effects by inhibiting HSCs proliferation and down-regulating Smad3 expression and phosphorylation through TGF-beta1 signalling.
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175
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Yu JC, Kwong TY, Luo Q, Cai Z. Photocatalytic oxidation of triclosan. CHEMOSPHERE 2006; 65:390-9. [PMID: 16571361 DOI: 10.1016/j.chemosphere.2006.02.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2005] [Revised: 02/07/2006] [Accepted: 02/07/2006] [Indexed: 05/08/2023]
Abstract
In the spring of 2003, there was an outbreak of the severe respiratory syndrome (SARS) in Hong Kong. Health concerns have thus triggered an increased and predominant use of various types of household cleansing agents such as triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol). However, it has been reported recently that triclosan could be photochemically converted to toxic 2,8-dichlorodibenzo-p-dioxin (2,8-Cl(2)DD) in the environment. It is therefore necessary to develop environmentally friendly methods for the treatment of triclosan. To this end, photocatalytic degradation of triclosan in aqueous solution was conducted using TiO(2) (Degussa P25) under irradiation of UV light (lambda < 365 nm). It was found that triclosan could be degraded by this approach. Hydrogen peroxide was added to enhance the degradation process, and the optimal initial hydrogen peroxide concentration for triclosan degradation was 0.005% (w/v). Product identification indicated that triclosan oxidation occurred at its phenol moiety and yielded quinone and hydroquinone intermediates. The formation of a dichlorophenol intermediate in triclosan degradation suggested bond-breaking of the ether linkage occurred during the process. Moreover, no chlorinated dibenzo-p-dioxin congener was detected. These findings confirm that the photocatalytic degradation of triclosan is an environmentally friendly process.
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176
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Luo Q, Huang H, Ding G, Chen X, Li B, Xu K. P-336. Fertil Steril 2006. [DOI: 10.1016/j.fertnstert.2006.07.692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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177
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Luo Q, Khoshgoftaar TM. Unsupervised multiscale color image segmentation based on MDL principle. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2006; 15:2755-61. [PMID: 16948319 DOI: 10.1109/tip.2006.877342] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We present an unsupervised multiscale color image segmentation algorithm. The basic idea is to apply mean shift clustering to obtain an over-segmentation and then merge regions at multiple scales to minimize the minimum description length criterion. The performance on the Berkeley segmentation benchmark campares favorably with some existing approaches.
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178
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Zhang JD, Xie Y, Schaefer HF, Luo Q, Li QS. Addition of hydrogen atom/hydride anion to the double bonds of cytosine tautomers: radical and anion structures and energetics. Mol Phys 2006. [DOI: 10.1080/00268970600653209] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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179
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Zhou Z, Calvert CC, Rainforth WM, Luo Q, Chen L, Hovsepian PE. Investigating worn surfaces of nanoscale TiAlN/VN multilayer coating using FIB and TEM. ACTA ACUST UNITED AC 2006. [DOI: 10.1088/1742-6596/26/1/022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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180
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Liu X, Luo Q, Peng Y, Wang J, Huang Y, Yang Z. Increase of the cure rate of burn patients by improving burn wound management methods. ANNALS OF BURNS AND FIRE DISASTERS 2005; 18:11-15. [PMID: 21990972 PMCID: PMC3187961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/27/2004] [Indexed: 05/31/2023]
Abstract
In order to summarize the progress of burn wound management of the patients in our burn ward and its correlation with the improvement of treatment results in the past 44 years, the general data (hospitalization time, cure rate, operation times) of 12,568 cases were analysed in terms of three periods, namely 1958 to 1980, 1981 to 1990, and 1991 to 2002. The bene?cial effects of the systemic application of recombinant human growth hormone, post-burn immediate escharectomy en masse, the external application of epithelial growth factor, and the coverage of split-thickness skin donor sites with razor-thick skin on wound healing and overall therapeutic results were also analysed. It was found that there was an increase in the number of burn patients admitted to our burn ward in recent decades. The overall cure rate, especially that of major burn patients, increased signi?cantly with the improvement of burn wound management. Hospitalization time was shortened and wound-healing time reduced. The analysis suggested that escharectomy en masse as early as possible, systemic application of growth hormone, and external application of epithelial growth factor are bene?cial to early burn wound healing.
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Abstract
The authors present a novel bipolar-coagulation microscissors exclusively designed for microsurgical use which can be applied easily, safely and effectively. The device is particularly helpful in the management (coagulation and cutting) of cerebral microvessels during the resection of brain tumors rich in vascularity or AVMs. The advantages of the instrument are the avoidance of exchanges of bipolar and microscissors under the microscope, reduction of fatigue for the operator, and decreases of operative time and blood loss while still achieving a good result.
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182
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Melrose DB, Luo Q. Wave dispersion near cyclotron resonance in pulsar plasmas. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2004; 70:016404. [PMID: 15324175 DOI: 10.1103/physreve.70.016404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2004] [Indexed: 05/24/2023]
Abstract
In a standard pulsar model, the radio emission is produced in the relativistic, strongly magnetized electron-positron plasma in the polar-cap region of the magnetosphere. Waves are generated well below the cyclotron frequency and must propagate through the cyclotron resonance region where they are affected by the resonance. Wave dispersion near the cyclotron resonance is discussed in the formalism of the weak anisotropy approximation in which the relevant waves are treated as transverse. Analytical approximations for the two orthogonal modes are derived, in the rest frame of the plasma, for nearly parallel, nearly antiparallel and nearly perpendicular propagation with respect to the magnetic field direction. It is shown that due to the relativistic distribution the wave dispersion varies smoothly across the resonance with initially elliptical polarization evolving to linear and then elliptical polarization with opposite handedness. The relevance of such a change in handedness to the interpretation of circular polarization is discussed.
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183
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Gravel JF, Luo Q, Boudreau D, Tang XP, Chin SL. Sensing of Halocarbons Using Femtosecond Laser-Induced Fluorescence. Anal Chem 2004; 76:4799-805. [PMID: 15307791 DOI: 10.1021/ac049425k] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A femtosecond laser-induced clean fluorescence technique was explored as a means to monitor halogenated alkanes in the atmosphere. Characteristic difluorocarbene radical (CF2) fluorescence in the UV-vis can be generated inside a femtosecond laser-induced filament for different halocarbons. We show that, due to different dissociation and excitation kinetics leading to fluorescence emission, it is possible to temporally resolve the characteristic fluorescence of CF2-containing halocarbons from that of background species, therefore enhancing the signal-to-noise ratio. Laboratory-scale experiments demonstrate the potential use of femtosecond laser-induced clean fluorescence for the remote sensing of halocarbons in the atmosphere. The combination of this detection strategy with LIDAR could allow the long-range monitoring of several atmospheric species with a single laser source, eventually leading to a better understanding of chemical and dynamic processes affecting global warming, ozone loss, tropospheric pollution, and weather prediction.
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184
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Chai XS, Hou Q, Luo Q, Zhu J. Rapid determination of hydrogen peroxide in the wood pulp bleaching streams by a dual-wavelength spectroscopic method. Anal Chim Acta 2004. [DOI: 10.1016/j.aca.2003.11.036] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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185
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Li A, Crimmins DL, Luo Q, Hartupee J, Landt Y, Ladenson JH, Wilson D, Anant S, Dieckgraefe BK. Expression of a novel regenerating gene product, Reg IV, by high density fermentation in Pichia pastoris: production, purification, and characterization. Protein Expr Purif 2003; 31:197-206. [PMID: 14550637 DOI: 10.1016/s1046-5928(03)00164-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Human regenerating (Reg) gene products are regionally expressed by gut-derived tissues, and are markedly up-regulated in cancer and in diseases characterized by mucosal injury. We recently identified Reg IV, a novel regenerating gene product that is uniquely expressed by the normal distal gastrointestinal mucosa. The function remains poorly understood due to the lack of significant purified Reg IV for biochemical and functional studies. Recombinant human Reg IV was efficiently expressed under the control of the AOX1 gene promoter in Pichia pastoris using the MutS strain KM71H. We describe the unique conditions that are required for efficient production of Reg IV protein in high density fermentation. Optimal protein expression was obtained by reduction of the fermentation temperature and addition of casamino acids as a supplemental nitrogen source and to minimize the activity of yeast produced proteases. Recombinant Reg IV protein was purified by tangential flow filtration and reverse phase chromatography. The purified protein was characterized by amino terminus sequence analysis and MALDI-TOFMS showing that the engineered protein had the expected sequence and molecular weight without secondary modification. Recombinant Reg IV was further characterized by specific monoclonal and polyclonal reagents that function for Western blot analysis and for immunolocalization studies.
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186
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Deng SB, Bai RB, Hu XM, Luo Q. Characteristics of a bioflocculant produced by Bacillus mucilaginosus and its use in starch wastewater treatment. Appl Microbiol Biotechnol 2003; 60:588-93. [PMID: 12536261 DOI: 10.1007/s00253-002-1159-5] [Citation(s) in RCA: 159] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2002] [Revised: 09/23/2002] [Accepted: 09/27/2002] [Indexed: 10/25/2022]
Abstract
A bioflocculant, MBFA9, was produced from a strain of bioflocculant-producing bacteria isolated from a soil sample and identified as Bacillus mucilaginosus. MBFA9 had a good flocculating capability and could achieve a flocculating rate of 99.6% for kaolin suspension at a dosage of only 0.1 ml/l. The major component of MBFA9 was found to be polysaccharide composed mainly of uronic acid (19.1%), neutral sugar (47.4%) and amino sugar (2.7%). Infrared spectrum analysis showed the presence of carboxyl and hydroxyl groups in the bioflocculant. MBFA9 is nontoxic and can be used in food industries for suspended solids (SS) recovery. When applied to starch wastewater treatment, MBFA9 greatly accelerated the formation of flocs and the settling of organic particles in the presence of Ca(2+) salt. After 5 min of settling, the removal rate of SS and chemical oxygen demand were up to 85.5% and 68.5%, respectively, which is better than traditional chemical flocculants.
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187
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Luo Q, Melrose DB, Fussell D. Wave dispersion in gyrotropic relativistic pulsar plasmas. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2002; 66:026405. [PMID: 12241295 DOI: 10.1103/physreve.66.026405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2002] [Indexed: 05/23/2023]
Abstract
Wave dispersion in a gyrotropic relativistic pulsar plasma is discussed. A pulsar plasma in general contains electrons, positrons, and possibly ions. Although electron-positron pairs are dominant in number density, charge neutrality is generally not satisfied and the gyrotropic terms need to be considered. These gyrotropic terms can lead to elliptical polarization that may be relevant for the observed circular polarization of pulsar radio emission. The wave dispersion and polarization are obtained numerically by calculating the response in terms of the three relativistic plasma dispersion functions. For waves propagating at an oblique angle (to the ambient magnetic field) a significant ellipticity requires the plasma to deviate substantially from the neutrality condition.
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188
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Zhu JY, Chai XS, Pan XJ, Luo Q, Li J. Quantification and reduction of organic sulfur compound formation in a commercial wood pulping process. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2002; 36:2269-2272. [PMID: 12038840 DOI: 10.1021/es011295z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study experimentally quantified the formation of organic sulfur compounds in a commercial SuperBatch kraft pulping process using a laboratory pilot-scale digester. The results indicate that wood chips not only can adsorb HS- but also methyl mercaptan (MM) in the black liquor used for pretreatment during the two pretreatment stages. The absorption rate of MM is much faster than that of HS-. In the third stage of SuperBatch pulping, the rate of formation of MM and dimethyl sulfide (DMS) is very similar to that found in conventional batch kraft pulping processes. The study examined the applicability of the phase transition cooking (PTC) concept for reducing organic sulfur compounds in pulping, previously developed in laboratory batch pulping using a bomb-type digester, in a SuperBatch process. It was confirmed that there is a phase transition point (PTP) corresponding to PTC in SuperBatch pulping beyond which further delignification significantly increases the formation of volatile organic sulfur compounds. The results indicate that a 40% reduction of TRS formation can be achieved by using PTC.
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189
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Machabeli GZ, Luo Q, Vladimirov SV, Melrose DB. Quasilinear diffusion as a result of modulational instability in the pulsar plasma. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2002; 65:036408. [PMID: 11909263 DOI: 10.1103/physreve.65.036408] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2001] [Indexed: 05/23/2023]
Abstract
Quasilinear diffusion due to modulational instability is considered in this paper. Interaction between the high-frequency, nearly transverse O mode (or the transverse X mode) and the low-frequency, nearly longitudinal L-O mode in a pulsar magnetospheric pair plasma can lead to modulational instability. The low-frequency L-O mode is superluminal, which is not subjected to usual Landau damping, and it is possible that excess wave energy is stored in this superluminal mode. The superluminal low-frequency L-O mode can dissipate in a way similar to the process of Langmuir wave collapse, that is, it cascades from the long- to short-wavelength regimes. When the phase speed becomes less than c, the waves can be damped through various resonances. We consider, in particular, damping through cyclotron resonance, which can lead to particle acceleration. The energetic beam particles, which have a very small spread initially, can develop a high-energy distribution tail, acquiring pitch angles through quasilinear diffusion. These particles can emit gamma rays through synchrotron radiation, contributing to the observed pulsar high-energy emission.
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190
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Chai XS, Luo Q, Zhu JY. Multiple headspace extraction-gas chromatographic method for the study of process kinetics. J Chromatogr A 2002; 946:177-83. [PMID: 11873967 DOI: 10.1016/s0021-9673(01)01532-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A multiple headspace extraction gas chromatographic technique to automate the study of process kinetics that involves volatile species was developed in this study. The technique was demonstrated by using it to study methanol formation in kraft black liquor samples under an isothermal temperature of 70 degrees C. The results indicate that methanol formation in kraft black liquors under isothermal conditions follows an exponential decay function. The present method is very simple, efficient and fully automated. It can be easily applied to study slow kinetic processes, such as reaction or adsorption and desorption, involving volatile species in any environmental and industrial samples with complicated matrices.
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191
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Wang X, Cai SX, Luo XD, Wang P, Luo Q, Liang GP, Yang ZC. [Modification of membrane lipid of human umbilical vein endothelia cells after direct lipopolysaccharide injury]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 2001; 53:419-24. [PMID: 11930218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Our previous study showed that the membrane viscosity of human umbilical vein endothelial cells (HUVECs) increased with lipopolysaccharide (LPS) concentration after direct LPS damaging, implying that LPS could change the membrane structure and composition of HUVECs. The purpose of the present study was to investigate the modification of HUVECs membrane lipid by LPS under direct LPS injury to HUVECs. Phospholipid components of HUVEC membrane were determined with high performance capillary electrophoresis (HPCE), and HUVECs were directly damaged by LPS of different concentrations: 0, 0.313, 0.625, 1.25, 2.5, 5 and 10 microgram/ml for 3 h, and by 0.625 microgram/ml for 1, 3, 6, 12, 24 and 48 h. The results show that total phospholipid content of HUVECs increased with the increase of LPS concentration at 3 h, and decreased with the duration of LPS effect at 0.625 microgram/ml. Phosphatidylinositol (PI) and phosphatidylcholine (PC) contents increased with the increase of LPS concentration and decreased with the duration of LPS effect; LPS contents and its effect duration had slight effect on sphingomyelin (SM), phosphatidylethanolamine (PE) or phosphatidylserine (PS) contents. The LPS activating effect of HUVEC membrane lipid showed a typical property of enzymatic dynamics. These experimental results indicate that LPS directly activates the metabolism of HUVEC membrane lipid and induces the modification of HUVEC membrane phospholipid, which implies that the mechanism of the impairment of HUVECs by LPS may be related to the membrane structure of HUVECs and the metabolism of HUVEC membrane lipid.
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192
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Yuan T, Luo Q. [Field study on the removal of arsenic from dispersed drinking water]. WEI SHENG YAN JIU = JOURNAL OF HYGIENE RESEARCH 2001; 30:329-30, 335. [PMID: 12561610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Shanyin county, an area prevalent of endemic arsenic poisoning in Shanxi Province, was selected as the experimental field to verify the methods studied for removal arsenic from dispersed drinking water. The results showed that the desired goal has been achieved from the field study. The results confirmed that arsenate could be removed from drinking water by using ferric sulfate or aluminum sulfate as coagulants and employing sand filtration. Javelle water(sodium hypochlorite) is an effective oxidant for arsenite. The performance of iron oxide-coated sand developed in this study was good for arsenic removal. Further study and application is needed.
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193
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Luo Q, Law CT. Propagation of nonparaxial beams with a modified Arnoldi method. OPTICS LETTERS 2001; 26:1708-1710. [PMID: 18049707 DOI: 10.1364/ol.26.001708] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We have developed a modified Arnoldi method that includes a complex square-root approximation, which excels at modeling the propagation of highly diverging beams in various media. Simulations of one transverse dimensional beam with an ultranarrow width and of cylindrical Gaussian beams with various divergence angles reveal the strength of this nonparaxial-beam propagation method.
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194
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Hong S, Wang D, Luo Q. [An new filling material of hair for the application of plastic surgery]. ZHONGHUA ZHENG XING WAI KE ZA ZHI = ZHONGHUA ZHENGXING WAIKE ZAZHI = CHINESE JOURNAL OF PLASTIC SURGERY 2001; 17:361-2. [PMID: 11838063] [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 investigate the possibility of hair as a filling material for reconstructive or cosmetic surgery. METHODS Sterilized pellets of hairs and silicone were selected and implanted subcutaneously in white rabbits. The clinical trial was carried out in 3 cases. RESULTS A thin fibrous capsule, with much few inflammatory cells, was formed around the implanted hair pellets in 3-4 months. The inflammatory cells disappeared in the 9th month. No implant rejection, granulomatous formation or hair degradation was showed. CONCLUSION Hair may be a valuable filling material for augmentation of the soft tissue.
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195
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Zou H, Luo Q, Zhou D. Affinity membrane chromatography for the analysis and purification of proteins. JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS 2001; 49:199-240. [PMID: 11694281 DOI: 10.1016/s0165-022x(01)00200-7] [Citation(s) in RCA: 187] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Affinity chromatography is unique among separation methods as it is the only technique that permits the purification of proteins based on biological functions rather than individual physical or chemical properties. The high specificity of affinity chromatography is due to the strong interaction between the ligand and the proteins of interest. Membrane separation allows the processing of a large amount of sample in a relatively short time owing to its structure, which provides a system with rapid reaction kinetics. The integration of membrane and affinity chromatography provides a number of advantages over traditional affinity chromatography with porous-bead packed columns, especially with regard to time and recovery of activity. This review gives detailed descriptions of materials used as membrane substrates, preparation of basic membranes, coupling of affinity ligands to membrane supports, and categories of affinity membrane cartridges. It also summarizes the applications of cellulose/glycidyl methacrylate composite membranes for proteins separation developed in our laboratory.
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196
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Moonis M, Lee B, Bailer RT, Luo Q, Montaner LJ. CCR5 and CXCR4 expression correlated with X4 and R5 HIV-1 infection yet not sustained replication in Th1 and Th2 cells. AIDS 2001; 15:1941-9. [PMID: 11600821 DOI: 10.1097/00002030-200110190-00005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To investigate the infectivity of T-helper (Th)1 and Th2 cells (derived from ccr5 wild-type and homozygous ccr5 Delta 32) to R5 and X4 HIV-1. DESIGN It remains unclear whether infection of Th1 and Th2 CD4 cells by R5 and X4 viruses mirrors their co-receptor expression profile as no direct quantitation of coreceptor levels and infection has been performed. In addition, it is unknown whether the lack of CCR5 expression affects the degree of Th1/Th2 polarization. METHODS Surface expression of CCR5 and CXCR4 was determined by quantitative fluorescence activated cell sorter analysis on in vitro differentiated Th1 and Th2 cells. R5 (Ba-L) and X4 (IIIB) HIV-1 isolates were used for infection studies and the efficiency of viral entry was determined by quantitative real time polymerase chain reaction detection of reverse transcribed proviral DNA. RESULTS Cell surface density of CCR5 molecules was eight-fold higher in Th1 versus Th2 subsets (P = 0.005) whereas CXCR4 surface density was four-fold higher in Th2 versus Th1 subsets (P = 0.006). Preferential infection and entry of Th1 cells by R5 HIV-1 was not associated with preferential replication, as eventually the R5-virus replicated to a higher level in Th2 cells in spite of lower initial viral infection/entry. By contrast, Th2 cells preferentially supported X4-virus infection and replication. High beta chemokine secretion by Th1 cells was associated with a lower R5 replication rate. CONCLUSIONS Th1 and Th2 cells differ in their infection efficiency for R5 and X4 HIV-1. ccr5 Delta 32-homozygous individuals maintain the ability for Th1/Th2 polarization, i.e., the expression of CCR5 is not required for Th1/Th2 polarization.
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197
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Sun L, Liu X, Qiu L, Wang J, Liu M, Fu D, Luo Q. Administration of plasmid DNA expressing human interleukin-6 significantly improves thrombocytopoiesis in irradiated mice. Ann Hematol 2001; 80:567-72. [PMID: 11732866 DOI: 10.1007/s002770100345] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
When people are exposed to large doses of ionizing rays in a short time, hematopoiesis is impaired and hemorrhage is one of the major clinical features. Suddenly decreasing platelet counts are responsible for the life-threatening hemorrhagic complication. Therefore, some cytokines have been used to improve thrombocytopoiesis in various radiation-induced thrombocytopenia models. Current measures for this purpose involve repeated intravenous or subcutaneous injections of recombinant proteins, which are expensive and inconvenient, or gene therapy with viral vectors that could not obviate the risk of infection. We tried to determine the possibility of gene therapy with plasmid vectors for radiation-induced hematopoietic injury, which could overcome the above-mentioned problem. In this study, we describe the enhanced efficiency of radiation on gene transfer with plasmid vector in vivo and the physiological role of expressed human interleukin-6 (hIL-6) in vivo on a radiation-induced thrombocytopenia model. After a single intramuscular injection of plasmid hIL-6 DNA on 6.5-Gy-irradiated mice, the hIL-6 protein level in mouse plasma was determined with enzyme-linked immunosorbent assay (ELISA). The level of hIL-6 began to increase from the 4th day, reached the peak value on about the 11th day, and remained at a higher level on the 28th day. Meanwhile, unirradiated mice injected with the same amount of plasmid DNA showed less hIL-6 on the 11th day after administration. Further experiments demonstrated that the hIL-6 level in 7.5-Gy-irradiated mice was about three times higher than that of 5.0-Gy-irradiated mice, suggesting radiation could improve gene transfer efficiency of plasmid DNA in vivo and might be dependent on radiation doses. The expression of hIL-6 in vivo showed a significant effect on hematopoietic recovery after radiation. Not only the platelet nadir in peripheral blood, but also the number of colony-forming cells in bone marrow rose. The increased platelet counts were partially due to the increase of reticulated platelet that reflected the activity of a given population of megakaryocyte in bone marrow. We conclude that radiation could significantly enhance the gene transfer efficiency of plasmid DNA and that gene therapy with plasmid vectors for radiation-induced hematopoietic injury might be more effective than other diseases without DNA repair.
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198
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Luo Q, Harmon E, Timms BG, Kretzner L. Novel expression patterns of the myc/max/mad transcription factor network in developing murine prostate gland. J Urol 2001; 166:1071-7. [PMID: 11490301] [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
PURPOSE Expression of myc proto-oncogenes and myc-antagonizing mad/mxi genes typically predominate in proliferating versus differentiating cells, respectively. C-myc expression in prostate cells is well established but to our knowledge that of several recently discovered mad/mxi genes is completely uncharacterized. Such characterization is particularly relevant because mxi1 is lost or mutated in some human prostate tumors and mouse mxi1-null mutants show prostatic hyperplasia. MATERIALS AND METHODS Developing murine prostatic lobes at select postnatal days 1 to 28 were analyzed by in situ immunohistochemical and in vitro RNA analysis. The expression patterns of the 3 myc genes c-, L- and N-myc, and the mad1, mxi1 and mad4 genes were studied in most detail with nonradioactive in situ and immunohistochemical analyses. RESULTS We describe what is to our knowledge previously unreported expression of N- and L-myc in the prostate with particularly the latter strongly expressed throughout development. High c-myc expression was lost at day 7 with re-elevation at day 14, followed by subsequent low expression, representing a unique in vivo confirmation of c-myc expression changes seen previously in several in vitro differentiation systems. The alternatively spliced weak and strong repressor mxi1 isoforms showed distinct, partially overlapping expression patterns. Of particular interest were continual mad1 and mad4 expression during the proliferative and differentiative phases. Similarly mad1 was evident in proliferating normal prostate cell cultures but not in tumor cell lines, suggesting that mad1 expression in prostate may be clinically relevant. CONCLUSIONS Myc network expression in developing mouse prostate is novel and does not completely fit previous simpler models of Myc versus Mad expression based on other cell types.
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199
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Luo Q, Zou H, Xiao X, Guo Z, Kong L, Mao X. Chromatographic separation of proteins on metal immobilized iminodiacetic acid-bound molded monolithic rods of macroporous poly(glycidyl methacrylate-co-ethylene dimethacrylate). J Chromatogr A 2001; 926:255-64. [PMID: 11556331 DOI: 10.1016/s0021-9673(01)01055-x] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Continuous rod of macroporous poly(glycidyl methacrylate-co-ethylene dimethacrylate) was prepared by a free radical polymerization within the confines of a stainless-steel column. The epoxide groups of the rod were modified by a reaction with iminodiacetic acid (IDA) that affords the active site to form metal IDA chelates used for immobilized metal affinity chromatography (IMAC). The efficiency of coupling of IDA to the epoxide-contained matrix was studied as a function of reaction time and temperature. High-performance separation of proteins, based on immobilized different metals on the column, were described. The influence of pH on the adsorption capacity of bovine serum albumin on the Cu2+-IDA continuous rod column was investigated in the range from 5.0 to 9.0. Purification of lysozyme from egg white and human serum albumin (HSA) on the commercially available HSA solution were performed on the naked IDA and Cu2+-IDA continuous rod columns, respectively; and the purity of the obtained fractions was detected by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry.
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200
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He W, Luo Q, Cheng N, Tang L. [A study of adhesion molecule expression in extraocular muscles of Graves' ophthalmopathy]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2001; 37:267-9. [PMID: 11864434] [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 investigate the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) in extraocular muscles (EOM) of the eyes with Graves' ophthalmopathy (GO). METHODS Seventeen EOM specimens obtained from 16 severe patients with GO and their cryostat sections were observed by double labeling immunohistochemical methods. RESULTS The expression of ICAM-1 was observed in interstitial and perimysial connective tissue surrounding EOM fibers, mononuclear cells, fibroblasts and vascular endothelial cells. Only were vascular endothelial cells stained for VCAM-1, and ICAM-1 and VCAM-1 immunoreactivities were not detected in EOM cells. CONCLUSIONS The findings indicate that ICAM-1 and VCAM-1 might be involved in the development of GO, and fibroblasts, vascular endothelial cells and mononuclear cells might play important roles in the autoimmune reaction.
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